freebsd-skq/sys/kern/vfs_syscalls.c

5000 lines
103 KiB
C
Raw Normal View History

/*-
1994-05-24 10:09:53 +00:00
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vfs_syscalls.c 8.13 (Berkeley) 4/15/94
*/
2003-06-11 00:56:59 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_capsicum.h"
#include "opt_compat.h"
#include "opt_kdtrace.h"
#include "opt_ktrace.h"
1994-05-24 10:09:53 +00:00
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/capability.h>
#include <sys/disk.h>
#include <sys/sysent.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/sysproto.h>
1994-05-24 10:09:53 +00:00
#include <sys/namei.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
1994-05-24 10:09:53 +00:00
#include <sys/file.h>
#include <sys/filio.h>
#include <sys/limits.h>
#include <sys/linker.h>
#include <sys/sdt.h>
1994-05-24 10:09:53 +00:00
#include <sys/stat.h>
#include <sys/sx.h>
#include <sys/unistd.h>
1994-05-24 10:09:53 +00:00
#include <sys/vnode.h>
#include <sys/priv.h>
1994-05-24 10:09:53 +00:00
#include <sys/proc.h>
#include <sys/dirent.h>
#include <sys/jail.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#ifdef KTRACE
#include <sys/ktrace.h>
#endif
1994-05-24 10:09:53 +00:00
#include <machine/stdarg.h>
#include <security/audit/audit.h>
#include <security/mac/mac_framework.h>
1994-05-24 10:09:53 +00:00
#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/uma.h>
1994-05-24 10:09:53 +00:00
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
static MALLOC_DEFINE(M_FADVISE, "fadvise", "posix_fadvise(2) information");
SDT_PROVIDER_DEFINE(vfs);
SDT_PROBE_DEFINE(vfs, , stat, mode, mode);
SDT_PROBE_ARGTYPE(vfs, , stat, mode, 0, "char *");
SDT_PROBE_ARGTYPE(vfs, , stat, mode, 1, "int");
SDT_PROBE_DEFINE(vfs, , stat, reg, reg);
SDT_PROBE_ARGTYPE(vfs, , stat, reg, 0, "char *");
SDT_PROBE_ARGTYPE(vfs, , stat, reg, 1, "int");
2002-03-19 21:25:46 +00:00
static int chroot_refuse_vdir_fds(struct filedesc *fdp);
static int getutimes(const struct timeval *, enum uio_seg, struct timespec *);
2002-03-19 21:25:46 +00:00
static int setfflags(struct thread *td, struct vnode *, int);
static int setutimes(struct thread *td, struct vnode *,
const struct timespec *, int, int);
2002-03-19 21:25:46 +00:00
static int vn_access(struct vnode *vp, int user_flags, struct ucred *cred,
struct thread *td);
/*
* The module initialization routine for POSIX asynchronous I/O will
* set this to the version of AIO that it implements. (Zero means
* that it is not implemented.) This value is used here by pathconf()
* and in kern_descrip.c by fpathconf().
*/
int async_io_version;
#ifdef DEBUG
static int syncprt = 0;
SYSCTL_INT(_debug, OID_AUTO, syncprt, CTLFLAG_RW, &syncprt, 0, "");
#endif
1994-05-24 10:09:53 +00:00
/*
* Sync each mounted filesystem.
*/
#ifndef _SYS_SYSPROTO_H_
struct sync_args {
int dummy;
};
#endif
1994-05-24 10:09:53 +00:00
/* ARGSUSED */
int
sys_sync(td, uap)
struct thread *td;
1994-05-24 10:09:53 +00:00
struct sync_args *uap;
{
struct mount *mp, *nmp;
int vfslocked;
1994-05-24 10:09:53 +00:00
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock(&mountlist_mtx);
for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
2008-11-02 10:15:42 +00:00
if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) {
nmp = TAILQ_NEXT(mp, mnt_list);
continue;
}
vfslocked = VFS_LOCK_GIANT(mp);
if ((mp->mnt_flag & MNT_RDONLY) == 0 &&
vn_start_write(NULL, &mp, V_NOWAIT) == 0) {
MNT_ILOCK(mp);
mp->mnt_noasync++;
mp->mnt_kern_flag &= ~MNTK_ASYNC;
MNT_IUNLOCK(mp);
vfs_msync(mp, MNT_NOWAIT);
VFS_SYNC(mp, MNT_NOWAIT);
MNT_ILOCK(mp);
mp->mnt_noasync--;
if ((mp->mnt_flag & MNT_ASYNC) != 0 &&
mp->mnt_noasync == 0)
mp->mnt_kern_flag |= MNTK_ASYNC;
MNT_IUNLOCK(mp);
vn_finished_write(mp);
1994-05-24 10:09:53 +00:00
}
VFS_UNLOCK_GIANT(vfslocked);
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock(&mountlist_mtx);
nmp = TAILQ_NEXT(mp, mnt_list);
vfs_unbusy(mp);
1994-05-24 10:09:53 +00:00
}
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock(&mountlist_mtx);
1994-05-24 10:09:53 +00:00
return (0);
}
/*
* Change filesystem quotas.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct quotactl_args {
char *path;
int cmd;
int uid;
caddr_t arg;
};
#endif
int
sys_quotactl(td, uap)
struct thread *td;
register struct quotactl_args /* {
char *path;
int cmd;
int uid;
caddr_t arg;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct mount *mp;
int vfslocked;
1994-05-24 10:09:53 +00:00
int error;
struct nameidata nd;
AUDIT_ARG_CMD(uap->cmd);
AUDIT_ARG_UID(uap->uid);
if (!prison_allow(td->td_ucred, PR_ALLOW_QUOTAS))
This Implements the mumbled about "Jail" feature. This is a seriously beefed up chroot kind of thing. The process is jailed along the same lines as a chroot does it, but with additional tough restrictions imposed on what the superuser can do. For all I know, it is safe to hand over the root bit inside a prison to the customer living in that prison, this is what it was developed for in fact: "real virtual servers". Each prison has an ip number associated with it, which all IP communications will be coerced to use and each prison has its own hostname. Needless to say, you need more RAM this way, but the advantage is that each customer can run their own particular version of apache and not stomp on the toes of their neighbors. It generally does what one would expect, but setting up a jail still takes a little knowledge. A few notes: I have no scripts for setting up a jail, don't ask me for them. The IP number should be an alias on one of the interfaces. mount a /proc in each jail, it will make ps more useable. /proc/<pid>/status tells the hostname of the prison for jailed processes. Quotas are only sensible if you have a mountpoint per prison. There are no privisions for stopping resource-hogging. Some "#ifdef INET" and similar may be missing (send patches!) If somebody wants to take it from here and develop it into more of a "virtual machine" they should be most welcome! Tools, comments, patches & documentation most welcome. Have fun... Sponsored by: http://www.rndassociates.com/ Run for almost a year by: http://www.servetheweb.com/
1999-04-28 11:38:52 +00:00
return (EPERM);
NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
UIO_USERSPACE, uap->path, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
mp = nd.ni_vp->v_mount;
vfs_ref(mp);
vput(nd.ni_vp);
error = vfs_busy(mp, 0);
vfs_rel(mp);
if (error) {
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
error = VFS_QUOTACTL(mp, uap->cmd, uap->uid, uap->arg);
vfs_unbusy(mp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Used by statfs conversion routines to scale the block size up if
* necessary so that all of the block counts are <= 'max_size'. Note
* that 'max_size' should be a bitmask, i.e. 2^n - 1 for some non-zero
* value of 'n'.
*/
void
statfs_scale_blocks(struct statfs *sf, long max_size)
{
uint64_t count;
int shift;
KASSERT(powerof2(max_size + 1), ("%s: invalid max_size", __func__));
/*
* Attempt to scale the block counts to give a more accurate
* overview to userland of the ratio of free space to used
* space. To do this, find the largest block count and compute
* a divisor that lets it fit into a signed integer <= max_size.
*/
if (sf->f_bavail < 0)
count = -sf->f_bavail;
else
count = sf->f_bavail;
count = MAX(sf->f_blocks, MAX(sf->f_bfree, count));
if (count <= max_size)
return;
count >>= flsl(max_size);
shift = 0;
while (count > 0) {
shift++;
count >>=1;
}
sf->f_bsize <<= shift;
sf->f_blocks >>= shift;
sf->f_bfree >>= shift;
sf->f_bavail >>= shift;
}
1994-05-24 10:09:53 +00:00
/*
* Get filesystem statistics.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct statfs_args {
char *path;
struct statfs *buf;
};
#endif
int
sys_statfs(td, uap)
struct thread *td;
register struct statfs_args /* {
char *path;
struct statfs *buf;
} */ *uap;
{
struct statfs sf;
int error;
error = kern_statfs(td, uap->path, UIO_USERSPACE, &sf);
if (error == 0)
error = copyout(&sf, uap->buf, sizeof(sf));
return (error);
}
int
kern_statfs(struct thread *td, char *path, enum uio_seg pathseg,
struct statfs *buf)
1994-05-24 10:09:53 +00:00
{
struct mount *mp;
struct statfs *sp, sb;
int vfslocked;
1994-05-24 10:09:53 +00:00
int error;
struct nameidata nd;
NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | MPSAFE |
AUDITVNODE1, pathseg, path, td);
error = namei(&nd);
if (error)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
mp = nd.ni_vp->v_mount;
vfs_ref(mp);
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_vp);
error = vfs_busy(mp, 0);
vfs_rel(mp);
if (error) {
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
#ifdef MAC
error = mac_mount_check_stat(td->td_ucred, mp);
if (error)
goto out;
#endif
/*
* Set these in case the underlying filesystem fails to do so.
*/
sp = &mp->mnt_stat;
sp->f_version = STATFS_VERSION;
sp->f_namemax = NAME_MAX;
sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
error = VFS_STATFS(mp, sp);
if (error)
goto out;
if (priv_check(td, PRIV_VFS_GENERATION)) {
2002-06-28 23:02:38 +00:00
bcopy(sp, &sb, sizeof(sb));
sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
prison_enforce_statfs(td->td_ucred, mp, &sb);
sp = &sb;
}
*buf = *sp;
out:
vfs_unbusy(mp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Get filesystem statistics.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct fstatfs_args {
int fd;
struct statfs *buf;
};
#endif
int
sys_fstatfs(td, uap)
struct thread *td;
register struct fstatfs_args /* {
int fd;
struct statfs *buf;
} */ *uap;
{
struct statfs sf;
int error;
error = kern_fstatfs(td, uap->fd, &sf);
if (error == 0)
error = copyout(&sf, uap->buf, sizeof(sf));
return (error);
}
int
kern_fstatfs(struct thread *td, int fd, struct statfs *buf)
1994-05-24 10:09:53 +00:00
{
struct file *fp;
struct mount *mp;
struct statfs *sp, sb;
int vfslocked;
struct vnode *vp;
1994-05-24 10:09:53 +00:00
int error;
AUDIT_ARG_FD(fd);
error = getvnode(td->td_proc->p_fd, fd, CAP_FSTATFS, &fp);
if (error)
1994-05-24 10:09:53 +00:00
return (error);
vp = fp->f_vnode;
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
vn_lock(vp, LK_SHARED | LK_RETRY);
#ifdef AUDIT
AUDIT_ARG_VNODE1(vp);
#endif
mp = vp->v_mount;
if (mp)
vfs_ref(mp);
VOP_UNLOCK(vp, 0);
fdrop(fp, td);
if (mp == NULL) {
error = EBADF;
goto out;
}
error = vfs_busy(mp, 0);
vfs_rel(mp);
if (error) {
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
#ifdef MAC
error = mac_mount_check_stat(td->td_ucred, mp);
if (error)
goto out;
#endif
/*
* Set these in case the underlying filesystem fails to do so.
*/
sp = &mp->mnt_stat;
sp->f_version = STATFS_VERSION;
sp->f_namemax = NAME_MAX;
sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
error = VFS_STATFS(mp, sp);
if (error)
goto out;
if (priv_check(td, PRIV_VFS_GENERATION)) {
2002-06-28 23:02:38 +00:00
bcopy(sp, &sb, sizeof(sb));
sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
prison_enforce_statfs(td->td_ucred, mp, &sb);
sp = &sb;
}
*buf = *sp;
out:
if (mp)
vfs_unbusy(mp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Get statistics on all filesystems.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct getfsstat_args {
struct statfs *buf;
long bufsize;
int flags;
};
#endif
int
sys_getfsstat(td, uap)
struct thread *td;
register struct getfsstat_args /* {
struct statfs *buf;
long bufsize;
int flags;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_getfsstat(td, &uap->buf, uap->bufsize, UIO_USERSPACE,
uap->flags));
}
/*
* If (bufsize > 0 && bufseg == UIO_SYSSPACE)
* The caller is responsible for freeing memory which will be allocated
* in '*buf'.
*/
int
kern_getfsstat(struct thread *td, struct statfs **buf, size_t bufsize,
enum uio_seg bufseg, int flags)
{
struct mount *mp, *nmp;
struct statfs *sfsp, *sp, sb;
size_t count, maxcount;
int vfslocked;
int error;
1994-05-24 10:09:53 +00:00
maxcount = bufsize / sizeof(struct statfs);
if (bufsize == 0)
sfsp = NULL;
else if (bufseg == UIO_USERSPACE)
sfsp = *buf;
else /* if (bufseg == UIO_SYSSPACE) */ {
count = 0;
mtx_lock(&mountlist_mtx);
TAILQ_FOREACH(mp, &mountlist, mnt_list) {
count++;
}
mtx_unlock(&mountlist_mtx);
if (maxcount > count)
maxcount = count;
sfsp = *buf = malloc(maxcount * sizeof(struct statfs), M_TEMP,
M_WAITOK);
}
count = 0;
mtx_lock(&mountlist_mtx);
for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
if (prison_canseemount(td->td_ucred, mp) != 0) {
nmp = TAILQ_NEXT(mp, mnt_list);
continue;
}
#ifdef MAC
if (mac_mount_check_stat(td->td_ucred, mp) != 0) {
nmp = TAILQ_NEXT(mp, mnt_list);
continue;
}
#endif
2008-11-02 10:15:42 +00:00
if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) {
nmp = TAILQ_NEXT(mp, mnt_list);
continue;
}
vfslocked = VFS_LOCK_GIANT(mp);
if (sfsp && count < maxcount) {
1994-05-24 10:09:53 +00:00
sp = &mp->mnt_stat;
/*
* Set these in case the underlying filesystem
* fails to do so.
*/
sp->f_version = STATFS_VERSION;
sp->f_namemax = NAME_MAX;
sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
1994-05-24 10:09:53 +00:00
/*
* If MNT_NOWAIT or MNT_LAZY is specified, do not
* refresh the fsstat cache. MNT_NOWAIT or MNT_LAZY
* overrides MNT_WAIT.
1994-05-24 10:09:53 +00:00
*/
if (((flags & (MNT_LAZY|MNT_NOWAIT)) == 0 ||
(flags & MNT_WAIT)) &&
(error = VFS_STATFS(mp, sp))) {
VFS_UNLOCK_GIANT(vfslocked);
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock(&mountlist_mtx);
nmp = TAILQ_NEXT(mp, mnt_list);
vfs_unbusy(mp);
1994-05-24 10:09:53 +00:00
continue;
}
if (priv_check(td, PRIV_VFS_GENERATION)) {
bcopy(sp, &sb, sizeof(sb));
sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
prison_enforce_statfs(td->td_ucred, mp, &sb);
sp = &sb;
}
if (bufseg == UIO_SYSSPACE)
bcopy(sp, sfsp, sizeof(*sp));
else /* if (bufseg == UIO_USERSPACE) */ {
error = copyout(sp, sfsp, sizeof(*sp));
if (error) {
vfs_unbusy(mp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
}
sfsp++;
1994-05-24 10:09:53 +00:00
}
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
count++;
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock(&mountlist_mtx);
nmp = TAILQ_NEXT(mp, mnt_list);
vfs_unbusy(mp);
1994-05-24 10:09:53 +00:00
}
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock(&mountlist_mtx);
1994-05-24 10:09:53 +00:00
if (sfsp && count > maxcount)
td->td_retval[0] = maxcount;
1994-05-24 10:09:53 +00:00
else
td->td_retval[0] = count;
1994-05-24 10:09:53 +00:00
return (0);
}
#ifdef COMPAT_FREEBSD4
/*
* Get old format filesystem statistics.
*/
static void cvtstatfs(struct statfs *, struct ostatfs *);
#ifndef _SYS_SYSPROTO_H_
struct freebsd4_statfs_args {
char *path;
struct ostatfs *buf;
};
#endif
int
freebsd4_statfs(td, uap)
struct thread *td;
struct freebsd4_statfs_args /* {
char *path;
struct ostatfs *buf;
} */ *uap;
{
struct ostatfs osb;
struct statfs sf;
int error;
error = kern_statfs(td, uap->path, UIO_USERSPACE, &sf);
if (error)
return (error);
cvtstatfs(&sf, &osb);
return (copyout(&osb, uap->buf, sizeof(osb)));
}
/*
* Get filesystem statistics.
*/
#ifndef _SYS_SYSPROTO_H_
struct freebsd4_fstatfs_args {
int fd;
struct ostatfs *buf;
};
#endif
int
freebsd4_fstatfs(td, uap)
struct thread *td;
struct freebsd4_fstatfs_args /* {
int fd;
struct ostatfs *buf;
} */ *uap;
{
struct ostatfs osb;
struct statfs sf;
int error;
error = kern_fstatfs(td, uap->fd, &sf);
if (error)
return (error);
cvtstatfs(&sf, &osb);
return (copyout(&osb, uap->buf, sizeof(osb)));
}
/*
* Get statistics on all filesystems.
*/
#ifndef _SYS_SYSPROTO_H_
struct freebsd4_getfsstat_args {
struct ostatfs *buf;
long bufsize;
int flags;
};
#endif
int
freebsd4_getfsstat(td, uap)
struct thread *td;
register struct freebsd4_getfsstat_args /* {
struct ostatfs *buf;
long bufsize;
int flags;
} */ *uap;
{
struct statfs *buf, *sp;
struct ostatfs osb;
size_t count, size;
int error;
count = uap->bufsize / sizeof(struct ostatfs);
size = count * sizeof(struct statfs);
error = kern_getfsstat(td, &buf, size, UIO_SYSSPACE, uap->flags);
if (size > 0) {
count = td->td_retval[0];
sp = buf;
while (count > 0 && error == 0) {
cvtstatfs(sp, &osb);
error = copyout(&osb, uap->buf, sizeof(osb));
sp++;
uap->buf++;
count--;
}
free(buf, M_TEMP);
}
return (error);
}
/*
* Implement fstatfs() for (NFS) file handles.
*/
#ifndef _SYS_SYSPROTO_H_
struct freebsd4_fhstatfs_args {
struct fhandle *u_fhp;
struct ostatfs *buf;
};
#endif
int
freebsd4_fhstatfs(td, uap)
struct thread *td;
struct freebsd4_fhstatfs_args /* {
struct fhandle *u_fhp;
struct ostatfs *buf;
} */ *uap;
{
struct ostatfs osb;
struct statfs sf;
fhandle_t fh;
int error;
error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
if (error)
return (error);
error = kern_fhstatfs(td, fh, &sf);
if (error)
return (error);
cvtstatfs(&sf, &osb);
return (copyout(&osb, uap->buf, sizeof(osb)));
}
/*
* Convert a new format statfs structure to an old format statfs structure.
*/
static void
cvtstatfs(nsp, osp)
struct statfs *nsp;
struct ostatfs *osp;
{
statfs_scale_blocks(nsp, LONG_MAX);
bzero(osp, sizeof(*osp));
osp->f_bsize = nsp->f_bsize;
osp->f_iosize = MIN(nsp->f_iosize, LONG_MAX);
osp->f_blocks = nsp->f_blocks;
osp->f_bfree = nsp->f_bfree;
osp->f_bavail = nsp->f_bavail;
osp->f_files = MIN(nsp->f_files, LONG_MAX);
osp->f_ffree = MIN(nsp->f_ffree, LONG_MAX);
osp->f_owner = nsp->f_owner;
osp->f_type = nsp->f_type;
osp->f_flags = nsp->f_flags;
osp->f_syncwrites = MIN(nsp->f_syncwrites, LONG_MAX);
osp->f_asyncwrites = MIN(nsp->f_asyncwrites, LONG_MAX);
osp->f_syncreads = MIN(nsp->f_syncreads, LONG_MAX);
osp->f_asyncreads = MIN(nsp->f_asyncreads, LONG_MAX);
strlcpy(osp->f_fstypename, nsp->f_fstypename,
MIN(MFSNAMELEN, OMFSNAMELEN));
strlcpy(osp->f_mntonname, nsp->f_mntonname,
MIN(MNAMELEN, OMNAMELEN));
strlcpy(osp->f_mntfromname, nsp->f_mntfromname,
MIN(MNAMELEN, OMNAMELEN));
osp->f_fsid = nsp->f_fsid;
}
#endif /* COMPAT_FREEBSD4 */
1994-05-24 10:09:53 +00:00
/*
* Change current working directory to a given file descriptor.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct fchdir_args {
int fd;
};
#endif
int
sys_fchdir(td, uap)
struct thread *td;
struct fchdir_args /* {
int fd;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
register struct filedesc *fdp = td->td_proc->p_fd;
struct vnode *vp, *tdp, *vpold;
struct mount *mp;
1994-05-24 10:09:53 +00:00
struct file *fp;
int vfslocked;
1994-05-24 10:09:53 +00:00
int error;
AUDIT_ARG_FD(uap->fd);
if ((error = getvnode(fdp, uap->fd, CAP_FCHDIR, &fp)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vp = fp->f_vnode;
VREF(vp);
fdrop(fp, td);
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
vn_lock(vp, LK_SHARED | LK_RETRY);
AUDIT_ARG_VNODE1(vp);
error = change_dir(vp, td);
while (!error && (mp = vp->v_mountedhere) != NULL) {
int tvfslocked;
2008-11-02 10:15:42 +00:00
if (vfs_busy(mp, 0))
continue;
tvfslocked = VFS_LOCK_GIANT(mp);
error = VFS_ROOT(mp, LK_SHARED, &tdp);
vfs_unbusy(mp);
if (error) {
VFS_UNLOCK_GIANT(tvfslocked);
break;
}
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
vp = tdp;
vfslocked = tvfslocked;
}
if (error) {
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
VOP_UNLOCK(vp, 0);
VFS_UNLOCK_GIANT(vfslocked);
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XLOCK(fdp);
vpold = fdp->fd_cdir;
1994-05-24 10:09:53 +00:00
fdp->fd_cdir = vp;
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XUNLOCK(fdp);
vfslocked = VFS_LOCK_GIANT(vpold->v_mount);
vrele(vpold);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (0);
}
/*
* Change current working directory (``.'').
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct chdir_args {
char *path;
};
#endif
int
sys_chdir(td, uap)
struct thread *td;
struct chdir_args /* {
char *path;
} */ *uap;
{
return (kern_chdir(td, uap->path, UIO_USERSPACE));
}
int
kern_chdir(struct thread *td, char *path, enum uio_seg pathseg)
1994-05-24 10:09:53 +00:00
{
register struct filedesc *fdp = td->td_proc->p_fd;
1994-05-24 10:09:53 +00:00
int error;
struct nameidata nd;
struct vnode *vp;
int vfslocked;
1994-05-24 10:09:53 +00:00
NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1 |
MPSAFE, pathseg, path, td);
if ((error = namei(&nd)) != 0)
return (error);
vfslocked = NDHASGIANT(&nd);
if ((error = change_dir(nd.ni_vp, td)) != 0) {
vput(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
NDFREE(&nd, NDF_ONLY_PNBUF);
1994-05-24 10:09:53 +00:00
return (error);
}
VOP_UNLOCK(nd.ni_vp, 0);
VFS_UNLOCK_GIANT(vfslocked);
NDFREE(&nd, NDF_ONLY_PNBUF);
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XLOCK(fdp);
vp = fdp->fd_cdir;
1994-05-24 10:09:53 +00:00
fdp->fd_cdir = nd.ni_vp;
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XUNLOCK(fdp);
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
vrele(vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (0);
}
/*
* Helper function for raised chroot(2) security function: Refuse if
* any filedescriptors are open directories.
*/
static int
chroot_refuse_vdir_fds(fdp)
struct filedesc *fdp;
{
struct vnode *vp;
struct file *fp;
int fd;
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_LOCK_ASSERT(fdp);
for (fd = 0; fd < fdp->fd_nfiles ; fd++) {
fp = fget_locked(fdp, fd);
if (fp == NULL)
continue;
if (fp->f_type == DTYPE_VNODE) {
vp = fp->f_vnode;
if (vp->v_type == VDIR)
return (EPERM);
}
}
return (0);
}
/*
* This sysctl determines if we will allow a process to chroot(2) if it
* has a directory open:
* 0: disallowed for all processes.
* 1: allowed for processes that were not already chroot(2)'ed.
* 2: allowed for all processes.
*/
static int chroot_allow_open_directories = 1;
SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW,
&chroot_allow_open_directories, 0, "");
1994-05-24 10:09:53 +00:00
/*
* Change notion of root (``/'') directory.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct chroot_args {
char *path;
};
#endif
int
sys_chroot(td, uap)
struct thread *td;
struct chroot_args /* {
char *path;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
error = priv_check(td, PRIV_VFS_CHROOT);
if (error)
1994-05-24 10:09:53 +00:00
return (error);
NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | MPSAFE |
AUDITVNODE1, UIO_USERSPACE, uap->path, td);
error = namei(&nd);
if (error)
goto error;
vfslocked = NDHASGIANT(&nd);
if ((error = change_dir(nd.ni_vp, td)) != 0)
goto e_vunlock;
#ifdef MAC
if ((error = mac_vnode_check_chroot(td->td_ucred, nd.ni_vp)))
goto e_vunlock;
#endif
VOP_UNLOCK(nd.ni_vp, 0);
error = change_root(nd.ni_vp, td);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
NDFREE(&nd, NDF_ONLY_PNBUF);
return (error);
e_vunlock:
vput(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
error:
NDFREE(&nd, NDF_ONLY_PNBUF);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Common routine for chroot and chdir. Callers must provide a locked vnode
* instance.
1994-05-24 10:09:53 +00:00
*/
int
change_dir(vp, td)
struct vnode *vp;
struct thread *td;
1994-05-24 10:09:53 +00:00
{
int error;
ASSERT_VOP_LOCKED(vp, "change_dir(): vp not locked");
1994-05-24 10:09:53 +00:00
if (vp->v_type != VDIR)
return (ENOTDIR);
#ifdef MAC
error = mac_vnode_check_chdir(td->td_ucred, vp);
1994-05-24 10:09:53 +00:00
if (error)
return (error);
#endif
error = VOP_ACCESS(vp, VEXEC, td->td_ucred, td);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Common routine for kern_chroot() and jail_attach(). The caller is
* responsible for invoking priv_check() and mac_vnode_check_chroot() to
* authorize this operation.
*/
int
change_root(vp, td)
struct vnode *vp;
struct thread *td;
{
struct filedesc *fdp;
struct vnode *oldvp;
int vfslocked;
int error;
VFS_ASSERT_GIANT(vp->v_mount);
fdp = td->td_proc->p_fd;
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XLOCK(fdp);
if (chroot_allow_open_directories == 0 ||
(chroot_allow_open_directories == 1 && fdp->fd_rdir != rootvnode)) {
error = chroot_refuse_vdir_fds(fdp);
if (error) {
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XUNLOCK(fdp);
return (error);
}
}
oldvp = fdp->fd_rdir;
fdp->fd_rdir = vp;
VREF(fdp->fd_rdir);
if (!fdp->fd_jdir) {
fdp->fd_jdir = vp;
VREF(fdp->fd_jdir);
}
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XUNLOCK(fdp);
vfslocked = VFS_LOCK_GIANT(oldvp->v_mount);
vrele(oldvp);
VFS_UNLOCK_GIANT(vfslocked);
return (0);
}
static __inline cap_rights_t
flags_to_rights(int flags)
{
cap_rights_t rights = 0;
switch ((flags & O_ACCMODE)) {
case O_RDONLY:
rights |= CAP_READ;
break;
case O_RDWR:
rights |= CAP_READ;
/* fall through */
case O_WRONLY:
rights |= CAP_WRITE;
break;
case O_EXEC:
rights |= CAP_FEXECVE;
break;
}
if (flags & O_CREAT)
rights |= CAP_CREATE;
if (flags & O_TRUNC)
rights |= CAP_FTRUNCATE;
if ((flags & O_EXLOCK) || (flags & O_SHLOCK))
rights |= CAP_FLOCK;
return (rights);
}
1994-05-24 10:09:53 +00:00
/*
* Check permissions, allocate an open file structure, and call the device
* open routine if any.
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct open_args {
char *path;
int flags;
int mode;
};
#endif
int
sys_open(td, uap)
struct thread *td;
register struct open_args /* {
char *path;
int flags;
int mode;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_open(td, uap->path, UIO_USERSPACE, uap->flags, uap->mode));
}
#ifndef _SYS_SYSPROTO_H_
struct openat_args {
int fd;
char *path;
int flag;
int mode;
};
#endif
int
sys_openat(struct thread *td, struct openat_args *uap)
{
return (kern_openat(td, uap->fd, uap->path, UIO_USERSPACE, uap->flag,
uap->mode));
}
int
kern_open(struct thread *td, char *path, enum uio_seg pathseg, int flags,
int mode)
{
return (kern_openat(td, AT_FDCWD, path, pathseg, flags, mode));
}
int
kern_openat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
int flags, int mode)
{
struct proc *p = td->td_proc;
struct filedesc *fdp = p->p_fd;
struct file *fp;
struct vnode *vp;
int cmode;
1994-05-24 10:09:53 +00:00
struct file *nfp;
int type, indx = -1, error, error_open;
1994-05-24 10:09:53 +00:00
struct flock lf;
struct nameidata nd;
int vfslocked;
cap_rights_t rights_needed = CAP_LOOKUP;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_FFLAGS(flags);
AUDIT_ARG_MODE(mode);
/* XXX: audit dirfd */
rights_needed |= flags_to_rights(flags);
/*
* Only one of the O_EXEC, O_RDONLY, O_WRONLY and O_RDWR flags
* may be specified.
*/
if (flags & O_EXEC) {
if (flags & O_ACCMODE)
return (EINVAL);
} else if ((flags & O_ACCMODE) == O_ACCMODE)
return (EINVAL);
else
flags = FFLAGS(flags);
/*
* allocate the file descriptor, but don't install a descriptor yet
*/
error = falloc_noinstall(td, &nfp);
if (error)
1994-05-24 10:09:53 +00:00
return (error);
/* An extra reference on `nfp' has been held for us by falloc_noinstall(). */
1994-05-24 10:09:53 +00:00
fp = nfp;
/* Set the flags early so the finit in devfs can pick them up. */
fp->f_flag = flags & FMASK;
cmode = ((mode &~ fdp->fd_cmask) & ALLPERMS) &~ S_ISTXT;
NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | AUDITVNODE1 | MPSAFE, pathseg,
path, fd, rights_needed, td);
td->td_dupfd = -1; /* XXX check for fdopen */
error = vn_open(&nd, &flags, cmode, fp);
if (error) {
/*
* If the vn_open replaced the method vector, something
* wonderous happened deep below and we just pass it up
* pretending we know what we do.
*/
if (error == ENXIO && fp->f_ops != &badfileops)
goto success;
/*
* handle special fdopen() case. bleh. dupfdopen() is
* responsible for dropping the old contents of ofiles[indx]
* if it succeeds.
*
* Don't do this for relative (capability) lookups; we don't
* understand exactly what would happen, and we don't think
* that it ever should.
*/
if ((nd.ni_strictrelative == 0) &&
(error == ENODEV || error == ENXIO) &&
(td->td_dupfd >= 0)) {
/* XXX from fdopen */
error_open = error;
if ((error = finstall(td, fp, &indx, flags)) != 0)
goto bad_unlocked;
if ((error = dupfdopen(td, fdp, indx, td->td_dupfd,
flags, error_open)) == 0)
goto success;
1994-05-24 10:09:53 +00:00
}
/*
* Clean up the descriptor, but only if another thread hadn't
* replaced or closed it.
*/
if (indx != -1)
fdclose(fdp, fp, indx, td);
fdrop(fp, td);
1994-05-24 10:09:53 +00:00
if (error == ERESTART)
error = EINTR;
return (error);
}
td->td_dupfd = 0;
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
/*
* Store the vnode, for any f_type. Typically, the vnode use
* count is decremented by direct call to vn_closefile() for
* files that switched type in the cdevsw fdopen() method.
*/
fp->f_vnode = vp;
/*
* If the file wasn't claimed by devfs bind it to the normal
* vnode operations here.
*/
if (fp->f_ops == &badfileops) {
KASSERT(vp->v_type != VFIFO, ("Unexpected fifo."));
fp->f_seqcount = 1;
finit(fp, flags & FMASK, DTYPE_VNODE, vp, &vnops);
}
VOP_UNLOCK(vp, 0);
if (fp->f_type == DTYPE_VNODE && (flags & (O_EXLOCK | O_SHLOCK)) != 0) {
1994-05-24 10:09:53 +00:00
lf.l_whence = SEEK_SET;
lf.l_start = 0;
lf.l_len = 0;
if (flags & O_EXLOCK)
lf.l_type = F_WRLCK;
else
lf.l_type = F_RDLCK;
type = F_FLOCK;
if ((flags & FNONBLOCK) == 0)
type |= F_WAIT;
2002-06-28 23:02:38 +00:00
if ((error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
type)) != 0)
goto bad;
atomic_set_int(&fp->f_flag, FHASLOCK);
1994-05-24 10:09:53 +00:00
}
if (flags & O_TRUNC) {
error = fo_truncate(fp, 0, td->td_ucred, td);
if (error)
goto bad;
}
VFS_UNLOCK_GIANT(vfslocked);
success:
/*
* If we haven't already installed the FD (for dupfdopen), do so now.
*/
if (indx == -1) {
#ifdef CAPABILITIES
if (nd.ni_strictrelative == 1) {
/*
* We are doing a strict relative lookup; wrap the
* result in a capability.
*/
if ((error = kern_capwrap(td, fp, nd.ni_baserights,
&indx)) != 0)
goto bad_unlocked;
} else
#endif
if ((error = finstall(td, fp, &indx, flags)) != 0)
goto bad_unlocked;
}
/*
* Release our private reference, leaving the one associated with
* the descriptor table intact.
*/
fdrop(fp, td);
td->td_retval[0] = indx;
1994-05-24 10:09:53 +00:00
return (0);
bad:
VFS_UNLOCK_GIANT(vfslocked);
bad_unlocked:
if (indx != -1)
fdclose(fdp, fp, indx, td);
fdrop(fp, td);
td->td_retval[0] = -1;
return (error);
1994-05-24 10:09:53 +00:00
}
#ifdef COMPAT_43
/*
* Create a file.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct ocreat_args {
char *path;
int mode;
};
#endif
int
ocreat(td, uap)
struct thread *td;
register struct ocreat_args /* {
char *path;
int mode;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_open(td, uap->path, UIO_USERSPACE,
O_WRONLY | O_CREAT | O_TRUNC, uap->mode));
1994-05-24 10:09:53 +00:00
}
#endif /* COMPAT_43 */
/*
* Create a special file.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct mknod_args {
char *path;
int mode;
int dev;
};
#endif
int
sys_mknod(td, uap)
struct thread *td;
register struct mknod_args /* {
char *path;
int mode;
int dev;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_mknod(td, uap->path, UIO_USERSPACE, uap->mode, uap->dev));
}
#ifndef _SYS_SYSPROTO_H_
struct mknodat_args {
int fd;
char *path;
mode_t mode;
dev_t dev;
};
#endif
int
sys_mknodat(struct thread *td, struct mknodat_args *uap)
{
return (kern_mknodat(td, uap->fd, uap->path, UIO_USERSPACE, uap->mode,
uap->dev));
}
int
kern_mknod(struct thread *td, char *path, enum uio_seg pathseg, int mode,
int dev)
{
return (kern_mknodat(td, AT_FDCWD, path, pathseg, mode, dev));
}
int
kern_mknodat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
int mode, int dev)
{
struct vnode *vp;
struct mount *mp;
1994-05-24 10:09:53 +00:00
struct vattr vattr;
int error;
int whiteout = 0;
1994-05-24 10:09:53 +00:00
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_MODE(mode);
AUDIT_ARG_DEV(dev);
switch (mode & S_IFMT) {
This Implements the mumbled about "Jail" feature. This is a seriously beefed up chroot kind of thing. The process is jailed along the same lines as a chroot does it, but with additional tough restrictions imposed on what the superuser can do. For all I know, it is safe to hand over the root bit inside a prison to the customer living in that prison, this is what it was developed for in fact: "real virtual servers". Each prison has an ip number associated with it, which all IP communications will be coerced to use and each prison has its own hostname. Needless to say, you need more RAM this way, but the advantage is that each customer can run their own particular version of apache and not stomp on the toes of their neighbors. It generally does what one would expect, but setting up a jail still takes a little knowledge. A few notes: I have no scripts for setting up a jail, don't ask me for them. The IP number should be an alias on one of the interfaces. mount a /proc in each jail, it will make ps more useable. /proc/<pid>/status tells the hostname of the prison for jailed processes. Quotas are only sensible if you have a mountpoint per prison. There are no privisions for stopping resource-hogging. Some "#ifdef INET" and similar may be missing (send patches!) If somebody wants to take it from here and develop it into more of a "virtual machine" they should be most welcome! Tools, comments, patches & documentation most welcome. Have fun... Sponsored by: http://www.rndassociates.com/ Run for almost a year by: http://www.servetheweb.com/
1999-04-28 11:38:52 +00:00
case S_IFCHR:
case S_IFBLK:
error = priv_check(td, PRIV_VFS_MKNOD_DEV);
break;
case S_IFMT:
error = priv_check(td, PRIV_VFS_MKNOD_BAD);
break;
case S_IFWHT:
error = priv_check(td, PRIV_VFS_MKNOD_WHT);
This Implements the mumbled about "Jail" feature. This is a seriously beefed up chroot kind of thing. The process is jailed along the same lines as a chroot does it, but with additional tough restrictions imposed on what the superuser can do. For all I know, it is safe to hand over the root bit inside a prison to the customer living in that prison, this is what it was developed for in fact: "real virtual servers". Each prison has an ip number associated with it, which all IP communications will be coerced to use and each prison has its own hostname. Needless to say, you need more RAM this way, but the advantage is that each customer can run their own particular version of apache and not stomp on the toes of their neighbors. It generally does what one would expect, but setting up a jail still takes a little knowledge. A few notes: I have no scripts for setting up a jail, don't ask me for them. The IP number should be an alias on one of the interfaces. mount a /proc in each jail, it will make ps more useable. /proc/<pid>/status tells the hostname of the prison for jailed processes. Quotas are only sensible if you have a mountpoint per prison. There are no privisions for stopping resource-hogging. Some "#ifdef INET" and similar may be missing (send patches!) If somebody wants to take it from here and develop it into more of a "virtual machine" they should be most welcome! Tools, comments, patches & documentation most welcome. Have fun... Sponsored by: http://www.rndassociates.com/ Run for almost a year by: http://www.servetheweb.com/
1999-04-28 11:38:52 +00:00
break;
case S_IFIFO:
if (dev == 0)
return (kern_mkfifoat(td, fd, path, pathseg, mode));
/* FALLTHROUGH */
This Implements the mumbled about "Jail" feature. This is a seriously beefed up chroot kind of thing. The process is jailed along the same lines as a chroot does it, but with additional tough restrictions imposed on what the superuser can do. For all I know, it is safe to hand over the root bit inside a prison to the customer living in that prison, this is what it was developed for in fact: "real virtual servers". Each prison has an ip number associated with it, which all IP communications will be coerced to use and each prison has its own hostname. Needless to say, you need more RAM this way, but the advantage is that each customer can run their own particular version of apache and not stomp on the toes of their neighbors. It generally does what one would expect, but setting up a jail still takes a little knowledge. A few notes: I have no scripts for setting up a jail, don't ask me for them. The IP number should be an alias on one of the interfaces. mount a /proc in each jail, it will make ps more useable. /proc/<pid>/status tells the hostname of the prison for jailed processes. Quotas are only sensible if you have a mountpoint per prison. There are no privisions for stopping resource-hogging. Some "#ifdef INET" and similar may be missing (send patches!) If somebody wants to take it from here and develop it into more of a "virtual machine" they should be most welcome! Tools, comments, patches & documentation most welcome. Have fun... Sponsored by: http://www.rndassociates.com/ Run for almost a year by: http://www.servetheweb.com/
1999-04-28 11:38:52 +00:00
default:
error = EINVAL;
This Implements the mumbled about "Jail" feature. This is a seriously beefed up chroot kind of thing. The process is jailed along the same lines as a chroot does it, but with additional tough restrictions imposed on what the superuser can do. For all I know, it is safe to hand over the root bit inside a prison to the customer living in that prison, this is what it was developed for in fact: "real virtual servers". Each prison has an ip number associated with it, which all IP communications will be coerced to use and each prison has its own hostname. Needless to say, you need more RAM this way, but the advantage is that each customer can run their own particular version of apache and not stomp on the toes of their neighbors. It generally does what one would expect, but setting up a jail still takes a little knowledge. A few notes: I have no scripts for setting up a jail, don't ask me for them. The IP number should be an alias on one of the interfaces. mount a /proc in each jail, it will make ps more useable. /proc/<pid>/status tells the hostname of the prison for jailed processes. Quotas are only sensible if you have a mountpoint per prison. There are no privisions for stopping resource-hogging. Some "#ifdef INET" and similar may be missing (send patches!) If somebody wants to take it from here and develop it into more of a "virtual machine" they should be most welcome! Tools, comments, patches & documentation most welcome. Have fun... Sponsored by: http://www.rndassociates.com/ Run for almost a year by: http://www.servetheweb.com/
1999-04-28 11:38:52 +00:00
break;
}
if (error)
1994-05-24 10:09:53 +00:00
return (error);
restart:
bwillwrite();
NDINIT_ATRIGHTS(&nd, CREATE,
LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE1, pathseg, path, fd,
CAP_MKFIFO, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
if (vp != NULL) {
NDFREE(&nd, NDF_ONLY_PNBUF);
if (vp == nd.ni_dvp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
vrele(vp);
VFS_UNLOCK_GIANT(vfslocked);
return (EEXIST);
} else {
1994-05-24 10:09:53 +00:00
VATTR_NULL(&vattr);
vattr.va_mode = (mode & ALLPERMS) &
~td->td_proc->p_fd->fd_cmask;
vattr.va_rdev = dev;
whiteout = 0;
1994-05-24 10:09:53 +00:00
switch (mode & S_IFMT) {
1994-05-24 10:09:53 +00:00
case S_IFMT: /* used by badsect to flag bad sectors */
vattr.va_type = VBAD;
break;
case S_IFCHR:
vattr.va_type = VCHR;
break;
case S_IFBLK:
vattr.va_type = VBLK;
break;
case S_IFWHT:
whiteout = 1;
break;
1994-05-24 10:09:53 +00:00
default:
panic("kern_mknod: invalid mode");
1994-05-24 10:09:53 +00:00
}
}
if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
VFS_UNLOCK_GIANT(vfslocked);
if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
return (error);
goto restart;
}
#ifdef MAC
if (error == 0 && !whiteout)
error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp,
&nd.ni_cnd, &vattr);
#endif
1994-05-24 10:09:53 +00:00
if (!error) {
if (whiteout)
error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, CREATE);
else {
error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp,
&nd.ni_cnd, &vattr);
1999-11-13 14:35:50 +00:00
if (error == 0)
vput(nd.ni_vp);
}
1994-05-24 10:09:53 +00:00
}
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Create a named pipe.
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct mkfifo_args {
char *path;
int mode;
};
#endif
int
sys_mkfifo(td, uap)
struct thread *td;
register struct mkfifo_args /* {
char *path;
int mode;
} */ *uap;
{
return (kern_mkfifo(td, uap->path, UIO_USERSPACE, uap->mode));
}
#ifndef _SYS_SYSPROTO_H_
struct mkfifoat_args {
int fd;
char *path;
mode_t mode;
};
#endif
int
sys_mkfifoat(struct thread *td, struct mkfifoat_args *uap)
{
return (kern_mkfifoat(td, uap->fd, uap->path, UIO_USERSPACE,
uap->mode));
}
int
kern_mkfifo(struct thread *td, char *path, enum uio_seg pathseg, int mode)
{
return (kern_mkfifoat(td, AT_FDCWD, path, pathseg, mode));
}
int
kern_mkfifoat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
int mode)
1994-05-24 10:09:53 +00:00
{
struct mount *mp;
1994-05-24 10:09:53 +00:00
struct vattr vattr;
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_MODE(mode);
restart:
bwillwrite();
NDINIT_AT(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE1,
pathseg, path, fd, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
if (nd.ni_vp != NULL) {
NDFREE(&nd, NDF_ONLY_PNBUF);
if (nd.ni_vp == nd.ni_dvp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (EEXIST);
}
if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
VFS_UNLOCK_GIANT(vfslocked);
if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
return (error);
goto restart;
}
1994-05-24 10:09:53 +00:00
VATTR_NULL(&vattr);
vattr.va_type = VFIFO;
vattr.va_mode = (mode & ALLPERMS) & ~td->td_proc->p_fd->fd_cmask;
#ifdef MAC
error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
&vattr);
if (error)
goto out;
#endif
error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
1999-11-13 14:35:50 +00:00
if (error == 0)
vput(nd.ni_vp);
#ifdef MAC
out:
#endif
vput(nd.ni_dvp);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
NDFREE(&nd, NDF_ONLY_PNBUF);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Make a hard file link.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct link_args {
char *path;
char *link;
};
#endif
int
sys_link(td, uap)
struct thread *td;
register struct link_args /* {
char *path;
char *link;
} */ *uap;
{
return (kern_link(td, uap->path, uap->link, UIO_USERSPACE));
}
#ifndef _SYS_SYSPROTO_H_
struct linkat_args {
int fd1;
char *path1;
int fd2;
char *path2;
int flag;
};
#endif
int
sys_linkat(struct thread *td, struct linkat_args *uap)
{
int flag;
flag = uap->flag;
if (flag & ~AT_SYMLINK_FOLLOW)
return (EINVAL);
return (kern_linkat(td, uap->fd1, uap->fd2, uap->path1, uap->path2,
UIO_USERSPACE, (flag & AT_SYMLINK_FOLLOW) ? FOLLOW : NOFOLLOW));
}
int hardlink_check_uid = 0;
SYSCTL_INT(_security_bsd, OID_AUTO, hardlink_check_uid, CTLFLAG_RW,
&hardlink_check_uid, 0,
"Unprivileged processes cannot create hard links to files owned by other "
"users");
static int hardlink_check_gid = 0;
SYSCTL_INT(_security_bsd, OID_AUTO, hardlink_check_gid, CTLFLAG_RW,
&hardlink_check_gid, 0,
"Unprivileged processes cannot create hard links to files owned by other "
"groups");
static int
can_hardlink(struct vnode *vp, struct ucred *cred)
{
struct vattr va;
int error;
if (!hardlink_check_uid && !hardlink_check_gid)
return (0);
error = VOP_GETATTR(vp, &va, cred);
if (error != 0)
return (error);
if (hardlink_check_uid && cred->cr_uid != va.va_uid) {
error = priv_check_cred(cred, PRIV_VFS_LINK, 0);
if (error)
return (error);
}
if (hardlink_check_gid && !groupmember(va.va_gid, cred)) {
error = priv_check_cred(cred, PRIV_VFS_LINK, 0);
if (error)
return (error);
}
return (0);
}
int
kern_link(struct thread *td, char *path, char *link, enum uio_seg segflg)
{
return (kern_linkat(td, AT_FDCWD, AT_FDCWD, path,link, segflg, FOLLOW));
}
int
kern_linkat(struct thread *td, int fd1, int fd2, char *path1, char *path2,
enum uio_seg segflg, int follow)
1994-05-24 10:09:53 +00:00
{
struct vnode *vp;
struct mount *mp;
1994-05-24 10:09:53 +00:00
struct nameidata nd;
int vfslocked;
int lvfslocked;
1994-05-24 10:09:53 +00:00
int error;
bwillwrite();
NDINIT_AT(&nd, LOOKUP, follow | MPSAFE | AUDITVNODE1, segflg, path1,
fd1, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
if (vp->v_type == VDIR) {
vrele(vp);
VFS_UNLOCK_GIANT(vfslocked);
return (EPERM); /* POSIX */
}
if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0) {
vrele(vp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
NDINIT_AT(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE2,
segflg, path2, fd2, td);
if ((error = namei(&nd)) == 0) {
lvfslocked = NDHASGIANT(&nd);
if (nd.ni_vp != NULL) {
if (nd.ni_dvp == nd.ni_vp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
vrele(nd.ni_vp);
error = EEXIST;
} else if ((error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY))
== 0) {
error = can_hardlink(vp, td->td_ucred);
if (error == 0)
#ifdef MAC
error = mac_vnode_check_link(td->td_ucred,
nd.ni_dvp, vp, &nd.ni_cnd);
if (error == 0)
#endif
error = VOP_LINK(nd.ni_dvp, vp, &nd.ni_cnd);
VOP_UNLOCK(vp, 0);
vput(nd.ni_dvp);
1994-05-24 10:09:53 +00:00
}
NDFREE(&nd, NDF_ONLY_PNBUF);
VFS_UNLOCK_GIANT(lvfslocked);
1994-05-24 10:09:53 +00:00
}
vrele(vp);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Make a symbolic link.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct symlink_args {
char *path;
char *link;
};
#endif
int
sys_symlink(td, uap)
struct thread *td;
register struct symlink_args /* {
char *path;
char *link;
} */ *uap;
{
return (kern_symlink(td, uap->path, uap->link, UIO_USERSPACE));
}
#ifndef _SYS_SYSPROTO_H_
struct symlinkat_args {
char *path;
int fd;
char *path2;
};
#endif
int
sys_symlinkat(struct thread *td, struct symlinkat_args *uap)
{
return (kern_symlinkat(td, uap->path1, uap->fd, uap->path2,
UIO_USERSPACE));
}
int
kern_symlink(struct thread *td, char *path, char *link, enum uio_seg segflg)
{
return (kern_symlinkat(td, path, AT_FDCWD, link, segflg));
}
int
kern_symlinkat(struct thread *td, char *path1, int fd, char *path2,
enum uio_seg segflg)
1994-05-24 10:09:53 +00:00
{
struct mount *mp;
1994-05-24 10:09:53 +00:00
struct vattr vattr;
char *syspath;
1994-05-24 10:09:53 +00:00
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
if (segflg == UIO_SYSSPACE) {
syspath = path1;
} else {
syspath = uma_zalloc(namei_zone, M_WAITOK);
if ((error = copyinstr(path1, syspath, MAXPATHLEN, NULL)) != 0)
goto out;
}
AUDIT_ARG_TEXT(syspath);
restart:
bwillwrite();
NDINIT_AT(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE1,
segflg, path2, fd, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
goto out;
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
if (nd.ni_vp) {
NDFREE(&nd, NDF_ONLY_PNBUF);
if (nd.ni_vp == nd.ni_dvp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
error = EEXIST;
goto out;
}
if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
VFS_UNLOCK_GIANT(vfslocked);
if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
goto out;
goto restart;
}
1994-05-24 10:09:53 +00:00
VATTR_NULL(&vattr);
vattr.va_mode = ACCESSPERMS &~ td->td_proc->p_fd->fd_cmask;
#ifdef MAC
vattr.va_type = VLNK;
error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
&vattr);
if (error)
goto out2;
#endif
error = VOP_SYMLINK(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr, syspath);
if (error == 0)
vput(nd.ni_vp);
#ifdef MAC
out2:
#endif
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
out:
if (segflg != UIO_SYSSPACE)
uma_zfree(namei_zone, syspath);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Delete a whiteout from the filesystem.
*/
int
sys_undelete(td, uap)
struct thread *td;
register struct undelete_args /* {
char *path;
} */ *uap;
{
int error;
struct mount *mp;
struct nameidata nd;
int vfslocked;
restart:
bwillwrite();
NDINIT(&nd, DELETE, LOCKPARENT | DOWHITEOUT | MPSAFE | AUDITVNODE1,
UIO_USERSPACE, uap->path, td);
error = namei(&nd);
if (error)
return (error);
vfslocked = NDHASGIANT(&nd);
if (nd.ni_vp != NULLVP || !(nd.ni_cnd.cn_flags & ISWHITEOUT)) {
NDFREE(&nd, NDF_ONLY_PNBUF);
if (nd.ni_vp == nd.ni_dvp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
if (nd.ni_vp)
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
return (EEXIST);
}
if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
VFS_UNLOCK_GIANT(vfslocked);
if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
return (error);
goto restart;
}
error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, DELETE);
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
1994-05-24 10:09:53 +00:00
/*
* Delete a name from the filesystem.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct unlink_args {
char *path;
};
#endif
int
sys_unlink(td, uap)
struct thread *td;
struct unlink_args /* {
char *path;
} */ *uap;
{
return (kern_unlink(td, uap->path, UIO_USERSPACE));
}
#ifndef _SYS_SYSPROTO_H_
struct unlinkat_args {
int fd;
char *path;
int flag;
};
#endif
int
sys_unlinkat(struct thread *td, struct unlinkat_args *uap)
{
int flag = uap->flag;
int fd = uap->fd;
char *path = uap->path;
if (flag & ~AT_REMOVEDIR)
return (EINVAL);
if (flag & AT_REMOVEDIR)
return (kern_rmdirat(td, fd, path, UIO_USERSPACE));
else
Background: When renaming a directory it passes through several intermediate states. First its new name will be created causing it to have two names (from possibly different parents). Next, if it has different parents, its value of ".." will be changed from pointing to the old parent to pointing to the new parent. Concurrently, its old name will be removed bringing it back into a consistent state. When fsck encounters an extra name for a directory, it offers to remove the "extraneous hard link"; when it finds that the names have been changed but the update to ".." has not happened, it offers to rewrite ".." to point at the correct parent. Both of these changes were considered unexpected so would cause fsck in preen mode or fsck in background mode to fail with the need to run fsck manually to fix these problems. Fsck running in preen mode or background mode now corrects these expected inconsistencies that arise during directory rename. The functionality added with this update is used by fsck running in background mode to make these fixes. Solution: This update adds three new fsck sysctl commands to support background fsck in correcting expected inconsistencies that arise from incomplete directory rename operations. They are: setcwd(dirinode) - set the current directory to dirinode in the filesystem associated with the snapshot. setdotdot(oldvalue, newvalue) - Verify that the inode number for ".." in the current directory is oldvalue then change it to newvalue. unlink(nameptr, oldvalue) - Verify that the inode number associated with nameptr in the current directory is oldvalue then unlink it. As with all other fsck sysctls, these new ones may only be used by processes with appropriate priviledge. Reported by: jeff Security issues: rwatson
2010-01-11 20:44:05 +00:00
return (kern_unlinkat(td, fd, path, UIO_USERSPACE, 0));
}
int
kern_unlink(struct thread *td, char *path, enum uio_seg pathseg)
{
Background: When renaming a directory it passes through several intermediate states. First its new name will be created causing it to have two names (from possibly different parents). Next, if it has different parents, its value of ".." will be changed from pointing to the old parent to pointing to the new parent. Concurrently, its old name will be removed bringing it back into a consistent state. When fsck encounters an extra name for a directory, it offers to remove the "extraneous hard link"; when it finds that the names have been changed but the update to ".." has not happened, it offers to rewrite ".." to point at the correct parent. Both of these changes were considered unexpected so would cause fsck in preen mode or fsck in background mode to fail with the need to run fsck manually to fix these problems. Fsck running in preen mode or background mode now corrects these expected inconsistencies that arise during directory rename. The functionality added with this update is used by fsck running in background mode to make these fixes. Solution: This update adds three new fsck sysctl commands to support background fsck in correcting expected inconsistencies that arise from incomplete directory rename operations. They are: setcwd(dirinode) - set the current directory to dirinode in the filesystem associated with the snapshot. setdotdot(oldvalue, newvalue) - Verify that the inode number for ".." in the current directory is oldvalue then change it to newvalue. unlink(nameptr, oldvalue) - Verify that the inode number associated with nameptr in the current directory is oldvalue then unlink it. As with all other fsck sysctls, these new ones may only be used by processes with appropriate priviledge. Reported by: jeff Security issues: rwatson
2010-01-11 20:44:05 +00:00
return (kern_unlinkat(td, AT_FDCWD, path, pathseg, 0));
}
int
Background: When renaming a directory it passes through several intermediate states. First its new name will be created causing it to have two names (from possibly different parents). Next, if it has different parents, its value of ".." will be changed from pointing to the old parent to pointing to the new parent. Concurrently, its old name will be removed bringing it back into a consistent state. When fsck encounters an extra name for a directory, it offers to remove the "extraneous hard link"; when it finds that the names have been changed but the update to ".." has not happened, it offers to rewrite ".." to point at the correct parent. Both of these changes were considered unexpected so would cause fsck in preen mode or fsck in background mode to fail with the need to run fsck manually to fix these problems. Fsck running in preen mode or background mode now corrects these expected inconsistencies that arise during directory rename. The functionality added with this update is used by fsck running in background mode to make these fixes. Solution: This update adds three new fsck sysctl commands to support background fsck in correcting expected inconsistencies that arise from incomplete directory rename operations. They are: setcwd(dirinode) - set the current directory to dirinode in the filesystem associated with the snapshot. setdotdot(oldvalue, newvalue) - Verify that the inode number for ".." in the current directory is oldvalue then change it to newvalue. unlink(nameptr, oldvalue) - Verify that the inode number associated with nameptr in the current directory is oldvalue then unlink it. As with all other fsck sysctls, these new ones may only be used by processes with appropriate priviledge. Reported by: jeff Security issues: rwatson
2010-01-11 20:44:05 +00:00
kern_unlinkat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
ino_t oldinum)
1994-05-24 10:09:53 +00:00
{
struct mount *mp;
struct vnode *vp;
1994-05-24 10:09:53 +00:00
int error;
struct nameidata nd;
Background: When renaming a directory it passes through several intermediate states. First its new name will be created causing it to have two names (from possibly different parents). Next, if it has different parents, its value of ".." will be changed from pointing to the old parent to pointing to the new parent. Concurrently, its old name will be removed bringing it back into a consistent state. When fsck encounters an extra name for a directory, it offers to remove the "extraneous hard link"; when it finds that the names have been changed but the update to ".." has not happened, it offers to rewrite ".." to point at the correct parent. Both of these changes were considered unexpected so would cause fsck in preen mode or fsck in background mode to fail with the need to run fsck manually to fix these problems. Fsck running in preen mode or background mode now corrects these expected inconsistencies that arise during directory rename. The functionality added with this update is used by fsck running in background mode to make these fixes. Solution: This update adds three new fsck sysctl commands to support background fsck in correcting expected inconsistencies that arise from incomplete directory rename operations. They are: setcwd(dirinode) - set the current directory to dirinode in the filesystem associated with the snapshot. setdotdot(oldvalue, newvalue) - Verify that the inode number for ".." in the current directory is oldvalue then change it to newvalue. unlink(nameptr, oldvalue) - Verify that the inode number associated with nameptr in the current directory is oldvalue then unlink it. As with all other fsck sysctls, these new ones may only be used by processes with appropriate priviledge. Reported by: jeff Security issues: rwatson
2010-01-11 20:44:05 +00:00
struct stat sb;
int vfslocked;
1994-05-24 10:09:53 +00:00
restart:
bwillwrite();
NDINIT_AT(&nd, DELETE, LOCKPARENT | LOCKLEAF | MPSAFE | AUDITVNODE1,
pathseg, path, fd, td);
if ((error = namei(&nd)) != 0)
return (error == EINVAL ? EPERM : error);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
Background: When renaming a directory it passes through several intermediate states. First its new name will be created causing it to have two names (from possibly different parents). Next, if it has different parents, its value of ".." will be changed from pointing to the old parent to pointing to the new parent. Concurrently, its old name will be removed bringing it back into a consistent state. When fsck encounters an extra name for a directory, it offers to remove the "extraneous hard link"; when it finds that the names have been changed but the update to ".." has not happened, it offers to rewrite ".." to point at the correct parent. Both of these changes were considered unexpected so would cause fsck in preen mode or fsck in background mode to fail with the need to run fsck manually to fix these problems. Fsck running in preen mode or background mode now corrects these expected inconsistencies that arise during directory rename. The functionality added with this update is used by fsck running in background mode to make these fixes. Solution: This update adds three new fsck sysctl commands to support background fsck in correcting expected inconsistencies that arise from incomplete directory rename operations. They are: setcwd(dirinode) - set the current directory to dirinode in the filesystem associated with the snapshot. setdotdot(oldvalue, newvalue) - Verify that the inode number for ".." in the current directory is oldvalue then change it to newvalue. unlink(nameptr, oldvalue) - Verify that the inode number associated with nameptr in the current directory is oldvalue then unlink it. As with all other fsck sysctls, these new ones may only be used by processes with appropriate priviledge. Reported by: jeff Security issues: rwatson
2010-01-11 20:44:05 +00:00
if (vp->v_type == VDIR && oldinum == 0) {
error = EPERM; /* POSIX */
Background: When renaming a directory it passes through several intermediate states. First its new name will be created causing it to have two names (from possibly different parents). Next, if it has different parents, its value of ".." will be changed from pointing to the old parent to pointing to the new parent. Concurrently, its old name will be removed bringing it back into a consistent state. When fsck encounters an extra name for a directory, it offers to remove the "extraneous hard link"; when it finds that the names have been changed but the update to ".." has not happened, it offers to rewrite ".." to point at the correct parent. Both of these changes were considered unexpected so would cause fsck in preen mode or fsck in background mode to fail with the need to run fsck manually to fix these problems. Fsck running in preen mode or background mode now corrects these expected inconsistencies that arise during directory rename. The functionality added with this update is used by fsck running in background mode to make these fixes. Solution: This update adds three new fsck sysctl commands to support background fsck in correcting expected inconsistencies that arise from incomplete directory rename operations. They are: setcwd(dirinode) - set the current directory to dirinode in the filesystem associated with the snapshot. setdotdot(oldvalue, newvalue) - Verify that the inode number for ".." in the current directory is oldvalue then change it to newvalue. unlink(nameptr, oldvalue) - Verify that the inode number associated with nameptr in the current directory is oldvalue then unlink it. As with all other fsck sysctls, these new ones may only be used by processes with appropriate priviledge. Reported by: jeff Security issues: rwatson
2010-01-11 20:44:05 +00:00
} else if (oldinum != 0 &&
((error = vn_stat(vp, &sb, td->td_ucred, NOCRED, td)) == 0) &&
sb.st_ino != oldinum) {
error = EIDRM; /* Identifier removed */
} else {
1994-05-24 10:09:53 +00:00
/*
* The root of a mounted filesystem cannot be deleted.
*
* XXX: can this only be a VDIR case?
1994-05-24 10:09:53 +00:00
*/
if (vp->v_vflag & VV_ROOT)
1994-05-24 10:09:53 +00:00
error = EBUSY;
}
if (error == 0) {
if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
if (vp == nd.ni_dvp)
vrele(vp);
else
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
if ((error = vn_start_write(NULL, &mp,
V_XSLEEP | PCATCH)) != 0)
return (error);
goto restart;
}
#ifdef MAC
error = mac_vnode_check_unlink(td->td_ucred, nd.ni_dvp, vp,
&nd.ni_cnd);
if (error)
goto out;
#endif
error = VOP_REMOVE(nd.ni_dvp, vp, &nd.ni_cnd);
#ifdef MAC
out:
#endif
vn_finished_write(mp);
1994-05-24 10:09:53 +00:00
}
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
if (vp == nd.ni_dvp)
vrele(vp);
else
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Reposition read/write file offset.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct lseek_args {
int fd;
int pad;
off_t offset;
int whence;
};
#endif
int
sys_lseek(td, uap)
struct thread *td;
register struct lseek_args /* {
int fd;
int pad;
off_t offset;
int whence;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct ucred *cred = td->td_ucred;
struct file *fp;
struct vnode *vp;
struct vattr vattr;
off_t offset, size;
int error, noneg;
int vfslocked;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_FD(uap->fd);
if ((error = fget(td, uap->fd, CAP_SEEK, &fp)) != 0)
return (error);
if (!(fp->f_ops->fo_flags & DFLAG_SEEKABLE)) {
fdrop(fp, td);
1994-05-24 10:09:53 +00:00
return (ESPIPE);
}
vp = fp->f_vnode;
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
noneg = (vp->v_type != VCHR);
2002-12-14 01:56:26 +00:00
offset = uap->offset;
switch (uap->whence) {
1994-05-24 10:09:53 +00:00
case L_INCR:
if (noneg &&
2001-08-29 18:35:53 +00:00
(fp->f_offset < 0 ||
(offset > 0 && fp->f_offset > OFF_MAX - offset))) {
error = EOVERFLOW;
break;
}
offset += fp->f_offset;
1994-05-24 10:09:53 +00:00
break;
case L_XTND:
vn_lock(vp, LK_SHARED | LK_RETRY);
error = VOP_GETATTR(vp, &vattr, cred);
VOP_UNLOCK(vp, 0);
if (error)
break;
/*
* If the file references a disk device, then fetch
* the media size and use that to determine the ending
* offset.
*/
if (vattr.va_size == 0 && vp->v_type == VCHR &&
fo_ioctl(fp, DIOCGMEDIASIZE, &size, cred, td) == 0)
vattr.va_size = size;
if (noneg &&
2001-08-29 18:35:53 +00:00
(vattr.va_size > OFF_MAX ||
(offset > 0 && vattr.va_size > OFF_MAX - offset))) {
error = EOVERFLOW;
break;
}
offset += vattr.va_size;
1994-05-24 10:09:53 +00:00
break;
case L_SET:
break;
case SEEK_DATA:
error = fo_ioctl(fp, FIOSEEKDATA, &offset, cred, td);
break;
case SEEK_HOLE:
error = fo_ioctl(fp, FIOSEEKHOLE, &offset, cred, td);
break;
1994-05-24 10:09:53 +00:00
default:
error = EINVAL;
}
if (error == 0 && noneg && offset < 0)
error = EINVAL;
if (error != 0)
goto drop;
fp->f_offset = offset;
*(off_t *)(td->td_retval) = fp->f_offset;
drop:
fdrop(fp, td);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
1994-05-24 10:09:53 +00:00
}
#if defined(COMPAT_43)
1994-05-24 10:09:53 +00:00
/*
* Reposition read/write file offset.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct olseek_args {
int fd;
long offset;
int whence;
};
#endif
int
olseek(td, uap)
struct thread *td;
register struct olseek_args /* {
int fd;
long offset;
int whence;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct lseek_args /* {
int fd;
int pad;
off_t offset;
int whence;
} */ nuap;
1994-05-24 10:09:53 +00:00
2002-12-14 01:56:26 +00:00
nuap.fd = uap->fd;
nuap.offset = uap->offset;
nuap.whence = uap->whence;
return (sys_lseek(td, &nuap));
1994-05-24 10:09:53 +00:00
}
#endif /* COMPAT_43 */
/* Version with the 'pad' argument */
int
freebsd6_lseek(td, uap)
struct thread *td;
register struct freebsd6_lseek_args *uap;
{
struct lseek_args ouap;
ouap.fd = uap->fd;
ouap.offset = uap->offset;
ouap.whence = uap->whence;
return (sys_lseek(td, &ouap));
}
1994-05-24 10:09:53 +00:00
/*
* Check access permissions using passed credentials.
*/
static int
vn_access(vp, user_flags, cred, td)
struct vnode *vp;
int user_flags;
struct ucred *cred;
struct thread *td;
{
int error;
accmode_t accmode;
/* Flags == 0 means only check for existence. */
error = 0;
if (user_flags) {
accmode = 0;
if (user_flags & R_OK)
accmode |= VREAD;
if (user_flags & W_OK)
accmode |= VWRITE;
if (user_flags & X_OK)
accmode |= VEXEC;
#ifdef MAC
error = mac_vnode_check_access(cred, vp, accmode);
if (error)
return (error);
#endif
if ((accmode & VWRITE) == 0 || (error = vn_writechk(vp)) == 0)
error = VOP_ACCESS(vp, accmode, cred, td);
}
return (error);
}
/*
* Check access permissions using "real" credentials.
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct access_args {
char *path;
int amode;
1994-05-24 10:09:53 +00:00
};
#endif
int
sys_access(td, uap)
struct thread *td;
register struct access_args /* {
char *path;
int amode;
} */ *uap;
{
return (kern_access(td, uap->path, UIO_USERSPACE, uap->amode));
}
#ifndef _SYS_SYSPROTO_H_
struct faccessat_args {
int dirfd;
char *path;
int amode;
int flag;
}
#endif
2008-10-23 21:50:16 +00:00
int
sys_faccessat(struct thread *td, struct faccessat_args *uap)
{
if (uap->flag & ~AT_EACCESS)
return (EINVAL);
return (kern_accessat(td, uap->fd, uap->path, UIO_USERSPACE, uap->flag,
uap->amode));
}
int
kern_access(struct thread *td, char *path, enum uio_seg pathseg, int amode)
{
return (kern_accessat(td, AT_FDCWD, path, pathseg, 0, amode));
}
int
kern_accessat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
int flag, int amode)
1994-05-24 10:09:53 +00:00
{
struct ucred *cred, *tmpcred;
struct vnode *vp;
1994-05-24 10:09:53 +00:00
struct nameidata nd;
int vfslocked;
int error;
1994-05-24 10:09:53 +00:00
/*
* Create and modify a temporary credential instead of one that
* is potentially shared.
*/
if (!(flag & AT_EACCESS)) {
cred = td->td_ucred;
tmpcred = crdup(cred);
tmpcred->cr_uid = cred->cr_ruid;
tmpcred->cr_groups[0] = cred->cr_rgid;
td->td_ucred = tmpcred;
} else
cred = tmpcred = td->td_ucred;
AUDIT_ARG_VALUE(amode);
NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | MPSAFE |
AUDITVNODE1, pathseg, path, fd, CAP_FSTAT, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
goto out1;
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
error = vn_access(vp, amode, tmpcred, td);
NDFREE(&nd, NDF_ONLY_PNBUF);
1994-05-24 10:09:53 +00:00
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
out1:
if (!(flag & AT_EACCESS)) {
td->td_ucred = cred;
crfree(tmpcred);
}
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Check access permissions using "effective" credentials.
*/
#ifndef _SYS_SYSPROTO_H_
struct eaccess_args {
char *path;
int amode;
};
#endif
int
sys_eaccess(td, uap)
struct thread *td;
register struct eaccess_args /* {
char *path;
int amode;
} */ *uap;
{
return (kern_eaccess(td, uap->path, UIO_USERSPACE, uap->amode));
}
int
kern_eaccess(struct thread *td, char *path, enum uio_seg pathseg, int amode)
{
return (kern_accessat(td, AT_FDCWD, path, pathseg, AT_EACCESS, amode));
}
#if defined(COMPAT_43)
1994-05-24 10:09:53 +00:00
/*
* Get file status; this version follows links.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct ostat_args {
char *path;
struct ostat *ub;
};
#endif
int
ostat(td, uap)
struct thread *td;
register struct ostat_args /* {
char *path;
struct ostat *ub;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct stat sb;
struct ostat osb;
int error;
error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
1994-05-24 10:09:53 +00:00
if (error)
return (error);
cvtstat(&sb, &osb);
2002-12-14 01:56:26 +00:00
error = copyout(&osb, uap->ub, sizeof (osb));
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Get file status; this version does not follow links.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct olstat_args {
char *path;
struct ostat *ub;
};
#endif
int
olstat(td, uap)
struct thread *td;
register struct olstat_args /* {
char *path;
struct ostat *ub;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct stat sb;
1994-05-24 10:09:53 +00:00
struct ostat osb;
int error;
error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
if (error)
return (error);
1994-05-24 10:09:53 +00:00
cvtstat(&sb, &osb);
2002-12-14 01:56:26 +00:00
error = copyout(&osb, uap->ub, sizeof (osb));
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Convert from an old to a new stat structure.
*/
void
1994-05-24 10:09:53 +00:00
cvtstat(st, ost)
struct stat *st;
struct ostat *ost;
{
ost->st_dev = st->st_dev;
ost->st_ino = st->st_ino;
ost->st_mode = st->st_mode;
ost->st_nlink = st->st_nlink;
ost->st_uid = st->st_uid;
ost->st_gid = st->st_gid;
ost->st_rdev = st->st_rdev;
if (st->st_size < (quad_t)1 << 32)
ost->st_size = st->st_size;
else
ost->st_size = -2;
ost->st_atim = st->st_atim;
ost->st_mtim = st->st_mtim;
ost->st_ctim = st->st_ctim;
1994-05-24 10:09:53 +00:00
ost->st_blksize = st->st_blksize;
ost->st_blocks = st->st_blocks;
ost->st_flags = st->st_flags;
ost->st_gen = st->st_gen;
}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
/*
* Get file status; this version follows links.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct stat_args {
char *path;
struct stat *ub;
};
#endif
int
sys_stat(td, uap)
struct thread *td;
register struct stat_args /* {
char *path;
struct stat *ub;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct stat sb;
int error;
error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
if (error == 0)
error = copyout(&sb, uap->ub, sizeof (sb));
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct fstatat_args {
int fd;
char *path;
struct stat *buf;
int flag;
}
#endif
int
sys_fstatat(struct thread *td, struct fstatat_args *uap)
{
struct stat sb;
int error;
error = kern_statat(td, uap->flag, uap->fd, uap->path,
UIO_USERSPACE, &sb);
if (error == 0)
error = copyout(&sb, uap->buf, sizeof (sb));
return (error);
}
int
kern_stat(struct thread *td, char *path, enum uio_seg pathseg, struct stat *sbp)
{
return (kern_statat(td, 0, AT_FDCWD, path, pathseg, sbp));
}
int
kern_statat(struct thread *td, int flag, int fd, char *path,
enum uio_seg pathseg, struct stat *sbp)
{
return (kern_statat_vnhook(td, flag, fd, path, pathseg, sbp, NULL));
}
int
kern_statat_vnhook(struct thread *td, int flag, int fd, char *path,
enum uio_seg pathseg, struct stat *sbp,
void (*hook)(struct vnode *vp, struct stat *sbp))
{
1994-05-24 10:09:53 +00:00
struct nameidata nd;
struct stat sb;
int error, vfslocked;
1994-05-24 10:09:53 +00:00
if (flag & ~AT_SYMLINK_NOFOLLOW)
return (EINVAL);
NDINIT_ATRIGHTS(&nd, LOOKUP, ((flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW :
FOLLOW) | LOCKSHARED | LOCKLEAF | AUDITVNODE1 | MPSAFE, pathseg,
path, fd, CAP_FSTAT, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
Make similar changes to fo_stat() and fo_poll() as made earlier to fo_read() and fo_write(): explicitly use the cred argument to fo_poll() as "active_cred" using the passed file descriptor's f_cred reference to provide access to the file credential. Add an active_cred argument to fo_stat() so that implementers have access to the active credential as well as the file credential. Generally modify callers of fo_stat() to pass in td->td_ucred rather than fp->f_cred, which was redundantly provided via the fp argument. This set of modifications also permits threads to perform these operations on behalf of another thread without modifying their credential. Trickle this change down into fo_stat/poll() implementations: - badfo_poll(), badfo_stat(): modify/add arguments. - kqueue_poll(), kqueue_stat(): modify arguments. - pipe_poll(), pipe_stat(): modify/add arguments, pass active_cred to MAC checks rather than td->td_ucred. - soo_poll(), soo_stat(): modify/add arguments, pass fp->f_cred rather than cred to pru_sopoll() to maintain current semantics. - sopoll(): moidfy arguments. - vn_poll(), vn_statfile(): modify/add arguments, pass new arguments to vn_stat(). Pass active_cred to MAC and fp->f_cred to VOP_POLL() to maintian current semantics. - vn_close(): rename cred to file_cred to reflect reality while I'm here. - vn_stat(): Add active_cred and file_cred arguments to vn_stat() and consumers so that this distinction is maintained at the VFS as well as 'struct file' layer. Pass active_cred instead of td->td_ucred to MAC and to VOP_GETATTR() to maintain current semantics. - fifofs: modify the creation of a "filetemp" so that the file credential is properly initialized and can be used in the socket code if desired. Pass ap->a_td->td_ucred as the active credential to soo_poll(). If we teach the vnop interface about the distinction between file and active credentials, we would use the active credential here. Note that current inconsistent passing of active_cred vs. file_cred to VOP's is maintained. It's not clear why GETATTR would be authorized using active_cred while POLL would be authorized using file_cred at the file system level. Obtained from: TrustedBSD Project Sponsored by: DARPA, NAI Labs
2002-08-16 12:52:03 +00:00
error = vn_stat(nd.ni_vp, &sb, td->td_ucred, NOCRED, td);
if (!error) {
SDT_PROBE(vfs, , stat, mode, path, sb.st_mode, 0, 0, 0);
if (S_ISREG(sb.st_mode))
SDT_PROBE(vfs, , stat, reg, path, pathseg, 0, 0, 0);
if (__predict_false(hook != NULL))
hook(nd.ni_vp, &sb);
}
NDFREE(&nd, NDF_ONLY_PNBUF);
1994-05-24 10:09:53 +00:00
vput(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
if (error)
return (error);
*sbp = sb;
#ifdef KTRACE
if (KTRPOINT(td, KTR_STRUCT))
ktrstat(&sb);
#endif
return (0);
1994-05-24 10:09:53 +00:00
}
/*
* Get file status; this version does not follow links.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct lstat_args {
char *path;
struct stat *ub;
};
#endif
int
sys_lstat(td, uap)
struct thread *td;
register struct lstat_args /* {
char *path;
struct stat *ub;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct stat sb;
1994-05-24 10:09:53 +00:00
int error;
error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
if (error == 0)
error = copyout(&sb, uap->ub, sizeof (sb));
return (error);
}
int
kern_lstat(struct thread *td, char *path, enum uio_seg pathseg, struct stat *sbp)
{
1994-05-24 10:09:53 +00:00
return (kern_statat(td, AT_SYMLINK_NOFOLLOW, AT_FDCWD, path, pathseg,
sbp));
1994-05-24 10:09:53 +00:00
}
/*
* Implementation of the NetBSD [l]stat() functions.
*/
void
cvtnstat(sb, nsb)
struct stat *sb;
struct nstat *nsb;
{
bzero(nsb, sizeof *nsb);
nsb->st_dev = sb->st_dev;
nsb->st_ino = sb->st_ino;
nsb->st_mode = sb->st_mode;
nsb->st_nlink = sb->st_nlink;
nsb->st_uid = sb->st_uid;
nsb->st_gid = sb->st_gid;
nsb->st_rdev = sb->st_rdev;
nsb->st_atim = sb->st_atim;
nsb->st_mtim = sb->st_mtim;
nsb->st_ctim = sb->st_ctim;
nsb->st_size = sb->st_size;
nsb->st_blocks = sb->st_blocks;
nsb->st_blksize = sb->st_blksize;
nsb->st_flags = sb->st_flags;
nsb->st_gen = sb->st_gen;
nsb->st_birthtim = sb->st_birthtim;
}
#ifndef _SYS_SYSPROTO_H_
struct nstat_args {
char *path;
struct nstat *ub;
};
#endif
int
sys_nstat(td, uap)
struct thread *td;
register struct nstat_args /* {
char *path;
struct nstat *ub;
} */ *uap;
{
struct stat sb;
struct nstat nsb;
int error;
error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
if (error)
return (error);
cvtnstat(&sb, &nsb);
2002-12-14 01:56:26 +00:00
error = copyout(&nsb, uap->ub, sizeof (nsb));
return (error);
}
/*
* NetBSD lstat. Get file status; this version does not follow links.
*/
#ifndef _SYS_SYSPROTO_H_
struct lstat_args {
char *path;
struct stat *ub;
};
#endif
int
sys_nlstat(td, uap)
struct thread *td;
register struct nlstat_args /* {
char *path;
struct nstat *ub;
} */ *uap;
{
struct stat sb;
struct nstat nsb;
int error;
error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
if (error)
return (error);
cvtnstat(&sb, &nsb);
2002-12-14 01:56:26 +00:00
error = copyout(&nsb, uap->ub, sizeof (nsb));
return (error);
}
1994-05-24 10:09:53 +00:00
/*
* Get configurable pathname variables.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct pathconf_args {
char *path;
int name;
};
#endif
int
sys_pathconf(td, uap)
struct thread *td;
register struct pathconf_args /* {
char *path;
int name;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_pathconf(td, uap->path, UIO_USERSPACE, uap->name, FOLLOW));
}
#ifndef _SYS_SYSPROTO_H_
struct lpathconf_args {
char *path;
int name;
};
#endif
int
sys_lpathconf(td, uap)
struct thread *td;
register struct lpathconf_args /* {
char *path;
int name;
} */ *uap;
{
return (kern_pathconf(td, uap->path, UIO_USERSPACE, uap->name, NOFOLLOW));
}
int
kern_pathconf(struct thread *td, char *path, enum uio_seg pathseg, int name,
u_long flags)
{
1994-05-24 10:09:53 +00:00
struct nameidata nd;
int error, vfslocked;
1994-05-24 10:09:53 +00:00
NDINIT(&nd, LOOKUP, LOCKSHARED | LOCKLEAF | MPSAFE | AUDITVNODE1 |
flags, pathseg, path, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
/* If asynchronous I/O is available, it works for all files. */
if (name == _PC_ASYNC_IO)
td->td_retval[0] = async_io_version;
else
error = VOP_PATHCONF(nd.ni_vp, name, td->td_retval);
1994-05-24 10:09:53 +00:00
vput(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Return target name of a symbolic link.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct readlink_args {
char *path;
char *buf;
size_t count;
1994-05-24 10:09:53 +00:00
};
#endif
int
sys_readlink(td, uap)
struct thread *td;
register struct readlink_args /* {
char *path;
char *buf;
size_t count;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_readlink(td, uap->path, UIO_USERSPACE, uap->buf,
UIO_USERSPACE, uap->count));
}
#ifndef _SYS_SYSPROTO_H_
struct readlinkat_args {
int fd;
char *path;
char *buf;
size_t bufsize;
};
#endif
int
sys_readlinkat(struct thread *td, struct readlinkat_args *uap)
{
return (kern_readlinkat(td, uap->fd, uap->path, UIO_USERSPACE,
uap->buf, UIO_USERSPACE, uap->bufsize));
}
int
kern_readlink(struct thread *td, char *path, enum uio_seg pathseg, char *buf,
enum uio_seg bufseg, size_t count)
{
return (kern_readlinkat(td, AT_FDCWD, path, pathseg, buf, bufseg,
count));
}
int
kern_readlinkat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
char *buf, enum uio_seg bufseg, size_t count)
{
struct vnode *vp;
1994-05-24 10:09:53 +00:00
struct iovec aiov;
struct uio auio;
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
if (count > INT_MAX)
return (EINVAL);
NDINIT_AT(&nd, LOOKUP, NOFOLLOW | LOCKSHARED | LOCKLEAF | MPSAFE |
AUDITVNODE1, pathseg, path, fd, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
NDFREE(&nd, NDF_ONLY_PNBUF);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
#ifdef MAC
error = mac_vnode_check_readlink(td->td_ucred, vp);
if (error) {
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
#endif
1994-05-24 10:09:53 +00:00
if (vp->v_type != VLNK)
error = EINVAL;
else {
aiov.iov_base = buf;
aiov.iov_len = count;
1994-05-24 10:09:53 +00:00
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = 0;
auio.uio_rw = UIO_READ;
auio.uio_segflg = bufseg;
auio.uio_td = td;
auio.uio_resid = count;
error = VOP_READLINK(vp, &auio, td->td_ucred);
1994-05-24 10:09:53 +00:00
}
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
td->td_retval[0] = count - auio.uio_resid;
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Common implementation code for chflags() and fchflags().
*/
static int
setfflags(td, vp, flags)
struct thread *td;
struct vnode *vp;
int flags;
{
int error;
struct mount *mp;
struct vattr vattr;
/*
* Prevent non-root users from setting flags on devices. When
* a device is reused, users can retain ownership of the device
* if they are allowed to set flags and programs assume that
* chown can't fail when done as root.
*/
if (vp->v_type == VCHR || vp->v_type == VBLK) {
error = priv_check(td, PRIV_VFS_CHFLAGS_DEV);
if (error)
return (error);
}
if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
return (error);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
VATTR_NULL(&vattr);
vattr.va_flags = flags;
#ifdef MAC
error = mac_vnode_check_setflags(td->td_ucred, vp, vattr.va_flags);
if (error == 0)
#endif
error = VOP_SETATTR(vp, &vattr, td->td_ucred);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
return (error);
}
1994-05-24 10:09:53 +00:00
/*
* Change flags of a file given a path name.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct chflags_args {
char *path;
int flags;
};
#endif
int
sys_chflags(td, uap)
struct thread *td;
register struct chflags_args /* {
char *path;
int flags;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_FFLAGS(uap->flags);
NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, UIO_USERSPACE,
uap->path, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
NDFREE(&nd, NDF_ONLY_PNBUF);
vfslocked = NDHASGIANT(&nd);
2002-12-14 01:56:26 +00:00
error = setfflags(td, nd.ni_vp, uap->flags);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Same as chflags() but doesn't follow symlinks.
*/
int
sys_lchflags(td, uap)
struct thread *td;
register struct lchflags_args /* {
char *path;
int flags;
} */ *uap;
{
int error;
struct nameidata nd;
int vfslocked;
AUDIT_ARG_FFLAGS(uap->flags);
NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE | AUDITVNODE1, UIO_USERSPACE,
uap->path, td);
if ((error = namei(&nd)) != 0)
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
2002-12-14 01:56:26 +00:00
error = setfflags(td, nd.ni_vp, uap->flags);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
1994-05-24 10:09:53 +00:00
/*
* Change flags of a file given a file descriptor.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct fchflags_args {
int fd;
int flags;
};
#endif
int
sys_fchflags(td, uap)
struct thread *td;
register struct fchflags_args /* {
int fd;
int flags;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct file *fp;
int vfslocked;
1994-05-24 10:09:53 +00:00
int error;
AUDIT_ARG_FD(uap->fd);
AUDIT_ARG_FFLAGS(uap->flags);
if ((error = getvnode(td->td_proc->p_fd, uap->fd, CAP_FCHFLAGS,
&fp)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
#ifdef AUDIT
vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
AUDIT_ARG_VNODE1(fp->f_vnode);
VOP_UNLOCK(fp->f_vnode, 0);
#endif
error = setfflags(td, fp->f_vnode, uap->flags);
VFS_UNLOCK_GIANT(vfslocked);
fdrop(fp, td);
return (error);
}
/*
* Common implementation code for chmod(), lchmod() and fchmod().
*/
int
setfmode(td, cred, vp, mode)
struct thread *td;
struct ucred *cred;
struct vnode *vp;
int mode;
{
int error;
struct mount *mp;
struct vattr vattr;
if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
return (error);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
VATTR_NULL(&vattr);
vattr.va_mode = mode & ALLPERMS;
#ifdef MAC
error = mac_vnode_check_setmode(cred, vp, vattr.va_mode);
if (error == 0)
#endif
error = VOP_SETATTR(vp, &vattr, cred);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Change mode of a file given path name.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct chmod_args {
char *path;
int mode;
};
#endif
int
sys_chmod(td, uap)
struct thread *td;
register struct chmod_args /* {
char *path;
int mode;
} */ *uap;
{
return (kern_chmod(td, uap->path, UIO_USERSPACE, uap->mode));
}
#ifndef _SYS_SYSPROTO_H_
struct fchmodat_args {
int dirfd;
char *path;
mode_t mode;
int flag;
}
#endif
int
sys_fchmodat(struct thread *td, struct fchmodat_args *uap)
{
int flag = uap->flag;
int fd = uap->fd;
char *path = uap->path;
mode_t mode = uap->mode;
if (flag & ~AT_SYMLINK_NOFOLLOW)
return (EINVAL);
return (kern_fchmodat(td, fd, path, UIO_USERSPACE, mode, flag));
}
int
kern_chmod(struct thread *td, char *path, enum uio_seg pathseg, int mode)
1994-05-24 10:09:53 +00:00
{
return (kern_fchmodat(td, AT_FDCWD, path, pathseg, mode, 0));
}
/*
* Change mode of a file given path name (don't follow links.)
*/
#ifndef _SYS_SYSPROTO_H_
struct lchmod_args {
char *path;
int mode;
};
#endif
int
sys_lchmod(td, uap)
struct thread *td;
register struct lchmod_args /* {
char *path;
int mode;
} */ *uap;
{
return (kern_fchmodat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
uap->mode, AT_SYMLINK_NOFOLLOW));
}
int
kern_fchmodat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
mode_t mode, int flag)
{
int error;
struct nameidata nd;
int vfslocked;
int follow;
AUDIT_ARG_MODE(mode);
follow = (flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW : FOLLOW;
NDINIT_ATRIGHTS(&nd, LOOKUP, follow | MPSAFE | AUDITVNODE1, pathseg,
path, fd, CAP_FCHMOD, td);
if ((error = namei(&nd)) != 0)
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
error = setfmode(td, td->td_ucred, nd.ni_vp, mode);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Change mode of a file given a file descriptor.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct fchmod_args {
int fd;
int mode;
};
#endif
int
sys_fchmod(struct thread *td, struct fchmod_args *uap)
1994-05-24 10:09:53 +00:00
{
struct file *fp;
int error;
AUDIT_ARG_FD(uap->fd);
AUDIT_ARG_MODE(uap->mode);
error = fget(td, uap->fd, CAP_FCHMOD, &fp);
if (error != 0)
1994-05-24 10:09:53 +00:00
return (error);
error = fo_chmod(fp, uap->mode, td->td_ucred, td);
fdrop(fp, td);
return (error);
}
/*
* Common implementation for chown(), lchown(), and fchown()
*/
int
setfown(td, cred, vp, uid, gid)
struct thread *td;
struct ucred *cred;
struct vnode *vp;
uid_t uid;
gid_t gid;
{
int error;
struct mount *mp;
struct vattr vattr;
if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
return (error);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
VATTR_NULL(&vattr);
vattr.va_uid = uid;
vattr.va_gid = gid;
#ifdef MAC
error = mac_vnode_check_setowner(cred, vp, vattr.va_uid,
vattr.va_gid);
if (error == 0)
#endif
error = VOP_SETATTR(vp, &vattr, cred);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Set ownership given a path name.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct chown_args {
char *path;
int uid;
int gid;
};
#endif
int
sys_chown(td, uap)
struct thread *td;
register struct chown_args /* {
char *path;
int uid;
int gid;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_chown(td, uap->path, UIO_USERSPACE, uap->uid, uap->gid));
}
#ifndef _SYS_SYSPROTO_H_
struct fchownat_args {
int fd;
const char * path;
uid_t uid;
gid_t gid;
int flag;
};
#endif
int
sys_fchownat(struct thread *td, struct fchownat_args *uap)
{
int flag;
flag = uap->flag;
if (flag & ~AT_SYMLINK_NOFOLLOW)
return (EINVAL);
return (kern_fchownat(td, uap->fd, uap->path, UIO_USERSPACE, uap->uid,
uap->gid, uap->flag));
}
int
kern_chown(struct thread *td, char *path, enum uio_seg pathseg, int uid,
int gid)
{
return (kern_fchownat(td, AT_FDCWD, path, pathseg, uid, gid, 0));
}
int
kern_fchownat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
int uid, int gid, int flag)
{
1994-05-24 10:09:53 +00:00
struct nameidata nd;
int error, vfslocked, follow;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_OWNER(uid, gid);
follow = (flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW : FOLLOW;
NDINIT_ATRIGHTS(&nd, LOOKUP, follow | MPSAFE | AUDITVNODE1, pathseg,
path, fd, CAP_FCHOWN, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
error = setfown(td, td->td_ucred, nd.ni_vp, uid, gid);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Set ownership given a path name, do not cross symlinks.
*/
#ifndef _SYS_SYSPROTO_H_
struct lchown_args {
char *path;
int uid;
int gid;
};
#endif
int
sys_lchown(td, uap)
struct thread *td;
register struct lchown_args /* {
char *path;
int uid;
int gid;
} */ *uap;
{
return (kern_lchown(td, uap->path, UIO_USERSPACE, uap->uid, uap->gid));
}
int
kern_lchown(struct thread *td, char *path, enum uio_seg pathseg, int uid,
int gid)
{
return (kern_fchownat(td, AT_FDCWD, path, pathseg, uid, gid,
AT_SYMLINK_NOFOLLOW));
}
1994-05-24 10:09:53 +00:00
/*
* Set ownership given a file descriptor.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct fchown_args {
int fd;
int uid;
int gid;
};
#endif
int
sys_fchown(td, uap)
struct thread *td;
register struct fchown_args /* {
int fd;
int uid;
int gid;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct file *fp;
int error;
AUDIT_ARG_FD(uap->fd);
AUDIT_ARG_OWNER(uap->uid, uap->gid);
error = fget(td, uap->fd, CAP_FCHOWN, &fp);
if (error != 0)
1994-05-24 10:09:53 +00:00
return (error);
error = fo_chown(fp, uap->uid, uap->gid, td->td_ucred, td);
fdrop(fp, td);
return (error);
}
/*
* Common implementation code for utimes(), lutimes(), and futimes().
*/
static int
getutimes(usrtvp, tvpseg, tsp)
const struct timeval *usrtvp;
enum uio_seg tvpseg;
struct timespec *tsp;
{
struct timeval tv[2];
const struct timeval *tvp;
int error;
if (usrtvp == NULL) {
vfs_timestamp(&tsp[0]);
tsp[1] = tsp[0];
} else {
if (tvpseg == UIO_SYSSPACE) {
tvp = usrtvp;
} else {
if ((error = copyin(usrtvp, tv, sizeof(tv))) != 0)
return (error);
tvp = tv;
}
2006-01-04 07:50:54 +00:00
if (tvp[0].tv_usec < 0 || tvp[0].tv_usec >= 1000000 ||
tvp[1].tv_usec < 0 || tvp[1].tv_usec >= 1000000)
return (EINVAL);
TIMEVAL_TO_TIMESPEC(&tvp[0], &tsp[0]);
TIMEVAL_TO_TIMESPEC(&tvp[1], &tsp[1]);
}
return (0);
}
/*
* Common implementation code for utimes(), lutimes(), and futimes().
*/
static int
setutimes(td, vp, ts, numtimes, nullflag)
struct thread *td;
struct vnode *vp;
const struct timespec *ts;
int numtimes;
int nullflag;
{
int error, setbirthtime;
struct mount *mp;
struct vattr vattr;
if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
return (error);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
setbirthtime = 0;
if (numtimes < 3 && !VOP_GETATTR(vp, &vattr, td->td_ucred) &&
timespeccmp(&ts[1], &vattr.va_birthtime, < ))
setbirthtime = 1;
VATTR_NULL(&vattr);
vattr.va_atime = ts[0];
vattr.va_mtime = ts[1];
if (setbirthtime)
vattr.va_birthtime = ts[1];
if (numtimes > 2)
vattr.va_birthtime = ts[2];
if (nullflag)
vattr.va_vaflags |= VA_UTIMES_NULL;
#ifdef MAC
error = mac_vnode_check_setutimes(td->td_ucred, vp, vattr.va_atime,
vattr.va_mtime);
#endif
if (error == 0)
error = VOP_SETATTR(vp, &vattr, td->td_ucred);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
return (error);
1994-05-24 10:09:53 +00:00
}
/*
* Set the access and modification times of a file.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct utimes_args {
char *path;
struct timeval *tptr;
};
#endif
int
sys_utimes(td, uap)
struct thread *td;
register struct utimes_args /* {
char *path;
struct timeval *tptr;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_utimes(td, uap->path, UIO_USERSPACE, uap->tptr,
UIO_USERSPACE));
}
#ifndef _SYS_SYSPROTO_H_
struct futimesat_args {
int fd;
const char * path;
const struct timeval * times;
};
#endif
int
sys_futimesat(struct thread *td, struct futimesat_args *uap)
{
return (kern_utimesat(td, uap->fd, uap->path, UIO_USERSPACE,
uap->times, UIO_USERSPACE));
}
int
kern_utimes(struct thread *td, char *path, enum uio_seg pathseg,
struct timeval *tptr, enum uio_seg tptrseg)
{
return (kern_utimesat(td, AT_FDCWD, path, pathseg, tptr, tptrseg));
}
int
kern_utimesat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
struct timeval *tptr, enum uio_seg tptrseg)
{
1994-05-24 10:09:53 +00:00
struct nameidata nd;
struct timespec ts[2];
int error, vfslocked;
1994-05-24 10:09:53 +00:00
if ((error = getutimes(tptr, tptrseg, ts)) != 0)
return (error);
NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, pathseg,
path, fd, CAP_FUTIMES, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
error = setutimes(td, nd.ni_vp, ts, 2, tptr == NULL);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Set the access and modification times of a file.
*/
#ifndef _SYS_SYSPROTO_H_
struct lutimes_args {
char *path;
struct timeval *tptr;
};
#endif
int
sys_lutimes(td, uap)
struct thread *td;
register struct lutimes_args /* {
char *path;
struct timeval *tptr;
} */ *uap;
{
return (kern_lutimes(td, uap->path, UIO_USERSPACE, uap->tptr,
UIO_USERSPACE));
}
int
kern_lutimes(struct thread *td, char *path, enum uio_seg pathseg,
struct timeval *tptr, enum uio_seg tptrseg)
{
struct timespec ts[2];
int error;
struct nameidata nd;
int vfslocked;
if ((error = getutimes(tptr, tptrseg, ts)) != 0)
return (error);
NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE | AUDITVNODE1, pathseg, path, td);
if ((error = namei(&nd)) != 0)
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
error = setutimes(td, nd.ni_vp, ts, 2, tptr == NULL);
vrele(nd.ni_vp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Set the access and modification times of a file.
*/
#ifndef _SYS_SYSPROTO_H_
struct futimes_args {
int fd;
struct timeval *tptr;
};
#endif
int
sys_futimes(td, uap)
struct thread *td;
register struct futimes_args /* {
int fd;
struct timeval *tptr;
} */ *uap;
{
return (kern_futimes(td, uap->fd, uap->tptr, UIO_USERSPACE));
}
int
kern_futimes(struct thread *td, int fd, struct timeval *tptr,
enum uio_seg tptrseg)
{
struct timespec ts[2];
struct file *fp;
int vfslocked;
int error;
AUDIT_ARG_FD(fd);
if ((error = getutimes(tptr, tptrseg, ts)) != 0)
return (error);
if ((error = getvnode(td->td_proc->p_fd, fd, CAP_FUTIMES, &fp))
!= 0)
return (error);
vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
#ifdef AUDIT
vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
AUDIT_ARG_VNODE1(fp->f_vnode);
VOP_UNLOCK(fp->f_vnode, 0);
#endif
error = setutimes(td, fp->f_vnode, ts, 2, tptr == NULL);
VFS_UNLOCK_GIANT(vfslocked);
fdrop(fp, td);
return (error);
}
1994-05-24 10:09:53 +00:00
/*
* Truncate a file given its path name.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct truncate_args {
char *path;
int pad;
off_t length;
};
#endif
int
sys_truncate(td, uap)
struct thread *td;
register struct truncate_args /* {
char *path;
int pad;
off_t length;
} */ *uap;
{
return (kern_truncate(td, uap->path, UIO_USERSPACE, uap->length));
}
int
kern_truncate(struct thread *td, char *path, enum uio_seg pathseg, off_t length)
1994-05-24 10:09:53 +00:00
{
struct mount *mp;
struct vnode *vp;
1994-05-24 10:09:53 +00:00
struct vattr vattr;
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
if (length < 0)
return(EINVAL);
NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, pathseg, path, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0) {
vrele(vp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
NDFREE(&nd, NDF_ONLY_PNBUF);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1994-05-24 10:09:53 +00:00
if (vp->v_type == VDIR)
error = EISDIR;
#ifdef MAC
else if ((error = mac_vnode_check_write(td->td_ucred, NOCRED, vp))) {
}
#endif
1994-05-24 10:09:53 +00:00
else if ((error = vn_writechk(vp)) == 0 &&
(error = VOP_ACCESS(vp, VWRITE, td->td_ucred, td)) == 0) {
1994-05-24 10:09:53 +00:00
VATTR_NULL(&vattr);
vattr.va_size = length;
error = VOP_SETATTR(vp, &vattr, td->td_ucred);
1994-05-24 10:09:53 +00:00
}
vput(vp);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
#if defined(COMPAT_43)
1994-05-24 10:09:53 +00:00
/*
* Truncate a file given its path name.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct otruncate_args {
char *path;
long length;
};
#endif
int
otruncate(td, uap)
struct thread *td;
register struct otruncate_args /* {
char *path;
long length;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct truncate_args /* {
char *path;
int pad;
off_t length;
} */ nuap;
2002-12-14 01:56:26 +00:00
nuap.path = uap->path;
nuap.length = uap->length;
return (sys_truncate(td, &nuap));
1994-05-24 10:09:53 +00:00
}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
/* Versions with the pad argument */
int
freebsd6_truncate(struct thread *td, struct freebsd6_truncate_args *uap)
{
struct truncate_args ouap;
ouap.path = uap->path;
ouap.length = uap->length;
return (sys_truncate(td, &ouap));
}
int
freebsd6_ftruncate(struct thread *td, struct freebsd6_ftruncate_args *uap)
{
struct ftruncate_args ouap;
ouap.fd = uap->fd;
ouap.length = uap->length;
return (sys_ftruncate(td, &ouap));
}
1994-05-24 10:09:53 +00:00
/*
* Sync an open file.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct fsync_args {
int fd;
};
#endif
int
sys_fsync(td, uap)
struct thread *td;
struct fsync_args /* {
int fd;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct vnode *vp;
struct mount *mp;
1994-05-24 10:09:53 +00:00
struct file *fp;
int vfslocked;
int error, lock_flags;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_FD(uap->fd);
if ((error = getvnode(td->td_proc->p_fd, uap->fd, CAP_FSYNC,
&fp)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vp = fp->f_vnode;
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
goto drop;
if (MNT_SHARED_WRITES(mp) ||
((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount))) {
lock_flags = LK_SHARED;
} else {
lock_flags = LK_EXCLUSIVE;
}
vn_lock(vp, lock_flags | LK_RETRY);
AUDIT_ARG_VNODE1(vp);
if (vp->v_object != NULL) {
VM_OBJECT_LOCK(vp->v_object);
vm_object_page_clean(vp->v_object, 0, 0, 0);
VM_OBJECT_UNLOCK(vp->v_object);
}
error = VOP_FSYNC(vp, MNT_WAIT, td);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
drop:
VFS_UNLOCK_GIANT(vfslocked);
fdrop(fp, td);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Rename files. Source and destination must either both be directories, or
* both not be directories. If target is a directory, it must be empty.
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct rename_args {
char *from;
char *to;
};
#endif
int
sys_rename(td, uap)
struct thread *td;
register struct rename_args /* {
char *from;
char *to;
} */ *uap;
{
return (kern_rename(td, uap->from, uap->to, UIO_USERSPACE));
}
#ifndef _SYS_SYSPROTO_H_
struct renameat_args {
int oldfd;
char *old;
int newfd;
char *new;
};
#endif
int
sys_renameat(struct thread *td, struct renameat_args *uap)
{
return (kern_renameat(td, uap->oldfd, uap->old, uap->newfd, uap->new,
UIO_USERSPACE));
}
int
kern_rename(struct thread *td, char *from, char *to, enum uio_seg pathseg)
{
return (kern_renameat(td, AT_FDCWD, from, AT_FDCWD, to, pathseg));
}
int
kern_renameat(struct thread *td, int oldfd, char *old, int newfd, char *new,
enum uio_seg pathseg)
1994-05-24 10:09:53 +00:00
{
struct mount *mp = NULL;
struct vnode *tvp, *fvp, *tdvp;
1994-05-24 10:09:53 +00:00
struct nameidata fromnd, tond;
int tvfslocked;
int fvfslocked;
1994-05-24 10:09:53 +00:00
int error;
bwillwrite();
#ifdef MAC
NDINIT_ATRIGHTS(&fromnd, DELETE, LOCKPARENT | LOCKLEAF | SAVESTART |
MPSAFE | AUDITVNODE1, pathseg, old, oldfd, CAP_DELETE, td);
#else
NDINIT_ATRIGHTS(&fromnd, DELETE, WANTPARENT | SAVESTART | MPSAFE |
AUDITVNODE1, pathseg, old, oldfd, CAP_DELETE, td);
#endif
if ((error = namei(&fromnd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
fvfslocked = NDHASGIANT(&fromnd);
tvfslocked = 0;
#ifdef MAC
error = mac_vnode_check_rename_from(td->td_ucred, fromnd.ni_dvp,
fromnd.ni_vp, &fromnd.ni_cnd);
VOP_UNLOCK(fromnd.ni_dvp, 0);
if (fromnd.ni_dvp != fromnd.ni_vp)
VOP_UNLOCK(fromnd.ni_vp, 0);
#endif
1994-05-24 10:09:53 +00:00
fvp = fromnd.ni_vp;
if (error == 0)
error = vn_start_write(fvp, &mp, V_WAIT | PCATCH);
if (error != 0) {
NDFREE(&fromnd, NDF_ONLY_PNBUF);
vrele(fromnd.ni_dvp);
vrele(fvp);
goto out1;
}
NDINIT_ATRIGHTS(&tond, RENAME, LOCKPARENT | LOCKLEAF | NOCACHE |
SAVESTART | MPSAFE | AUDITVNODE2, pathseg, new, newfd, CAP_CREATE,
td);
if (fromnd.ni_vp->v_type == VDIR)
tond.ni_cnd.cn_flags |= WILLBEDIR;
if ((error = namei(&tond)) != 0) {
/* Translate error code for rename("dir1", "dir2/."). */
if (error == EISDIR && fvp->v_type == VDIR)
error = EINVAL;
NDFREE(&fromnd, NDF_ONLY_PNBUF);
1994-05-24 10:09:53 +00:00
vrele(fromnd.ni_dvp);
vrele(fvp);
vn_finished_write(mp);
1994-05-24 10:09:53 +00:00
goto out1;
}
tvfslocked = NDHASGIANT(&tond);
1994-05-24 10:09:53 +00:00
tdvp = tond.ni_dvp;
tvp = tond.ni_vp;
if (tvp != NULL) {
if (fvp->v_type == VDIR && tvp->v_type != VDIR) {
error = ENOTDIR;
goto out;
} else if (fvp->v_type != VDIR && tvp->v_type == VDIR) {
error = EISDIR;
goto out;
}
}
if (fvp == tdvp) {
1994-05-24 10:09:53 +00:00
error = EINVAL;
goto out;
}
1994-05-24 10:09:53 +00:00
/*
* If the source is the same as the destination (that is, if they
* are links to the same vnode), then there is nothing to do.
1994-05-24 10:09:53 +00:00
*/
if (fvp == tvp)
1994-05-24 10:09:53 +00:00
error = -1;
#ifdef MAC
else
error = mac_vnode_check_rename_to(td->td_ucred, tdvp,
tond.ni_vp, fromnd.ni_dvp == tdvp, &tond.ni_cnd);
#endif
1994-05-24 10:09:53 +00:00
out:
if (!error) {
error = VOP_RENAME(fromnd.ni_dvp, fromnd.ni_vp, &fromnd.ni_cnd,
tond.ni_dvp, tond.ni_vp, &tond.ni_cnd);
NDFREE(&fromnd, NDF_ONLY_PNBUF);
NDFREE(&tond, NDF_ONLY_PNBUF);
1994-05-24 10:09:53 +00:00
} else {
NDFREE(&fromnd, NDF_ONLY_PNBUF);
NDFREE(&tond, NDF_ONLY_PNBUF);
if (tvp)
vput(tvp);
1994-05-24 10:09:53 +00:00
if (tdvp == tvp)
vrele(tdvp);
else
vput(tdvp);
vrele(fromnd.ni_dvp);
vrele(fvp);
}
vrele(tond.ni_startdir);
vn_finished_write(mp);
out1:
1994-05-24 10:09:53 +00:00
if (fromnd.ni_startdir)
vrele(fromnd.ni_startdir);
VFS_UNLOCK_GIANT(fvfslocked);
VFS_UNLOCK_GIANT(tvfslocked);
1994-05-24 10:09:53 +00:00
if (error == -1)
return (0);
return (error);
}
/*
* Make a directory file.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct mkdir_args {
char *path;
int mode;
};
#endif
int
sys_mkdir(td, uap)
struct thread *td;
register struct mkdir_args /* {
char *path;
int mode;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
return (kern_mkdir(td, uap->path, UIO_USERSPACE, uap->mode));
}
#ifndef _SYS_SYSPROTO_H_
struct mkdirat_args {
int fd;
char *path;
mode_t mode;
};
#endif
int
sys_mkdirat(struct thread *td, struct mkdirat_args *uap)
{
return (kern_mkdirat(td, uap->fd, uap->path, UIO_USERSPACE, uap->mode));
}
int
kern_mkdir(struct thread *td, char *path, enum uio_seg segflg, int mode)
{
return (kern_mkdirat(td, AT_FDCWD, path, segflg, mode));
}
int
kern_mkdirat(struct thread *td, int fd, char *path, enum uio_seg segflg,
int mode)
{
struct mount *mp;
struct vnode *vp;
1994-05-24 10:09:53 +00:00
struct vattr vattr;
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_MODE(mode);
restart:
bwillwrite();
NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE |
AUDITVNODE1, segflg, path, fd, CAP_MKDIR, td);
nd.ni_cnd.cn_flags |= WILLBEDIR;
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
if (vp != NULL) {
NDFREE(&nd, NDF_ONLY_PNBUF);
/*
* XXX namei called with LOCKPARENT but not LOCKLEAF has
* the strange behaviour of leaving the vnode unlocked
* if the target is the same vnode as the parent.
*/
if (vp == nd.ni_dvp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
vrele(vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (EEXIST);
}
if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
VFS_UNLOCK_GIANT(vfslocked);
if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
return (error);
goto restart;
}
1994-05-24 10:09:53 +00:00
VATTR_NULL(&vattr);
vattr.va_type = VDIR;
vattr.va_mode = (mode & ACCESSPERMS) &~ td->td_proc->p_fd->fd_cmask;
#ifdef MAC
error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
&vattr);
if (error)
goto out;
#endif
1994-05-24 10:09:53 +00:00
error = VOP_MKDIR(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
#ifdef MAC
out:
#endif
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(nd.ni_dvp);
1994-05-24 10:09:53 +00:00
if (!error)
vput(nd.ni_vp);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Remove a directory file.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct rmdir_args {
char *path;
};
#endif
int
sys_rmdir(td, uap)
struct thread *td;
struct rmdir_args /* {
char *path;
} */ *uap;
{
return (kern_rmdir(td, uap->path, UIO_USERSPACE));
}
int
kern_rmdir(struct thread *td, char *path, enum uio_seg pathseg)
{
return (kern_rmdirat(td, AT_FDCWD, path, pathseg));
}
int
kern_rmdirat(struct thread *td, int fd, char *path, enum uio_seg pathseg)
1994-05-24 10:09:53 +00:00
{
struct mount *mp;
struct vnode *vp;
1994-05-24 10:09:53 +00:00
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
restart:
bwillwrite();
NDINIT_ATRIGHTS(&nd, DELETE, LOCKPARENT | LOCKLEAF | MPSAFE |
AUDITVNODE1, pathseg, path, fd, CAP_RMDIR, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
if (vp->v_type != VDIR) {
error = ENOTDIR;
goto out;
}
/*
* No rmdir "." please.
*/
if (nd.ni_dvp == vp) {
error = EINVAL;
goto out;
}
/*
* The root of a mounted filesystem cannot be deleted.
*/
if (vp->v_vflag & VV_ROOT) {
1994-05-24 10:09:53 +00:00
error = EBUSY;
goto out;
1994-05-24 10:09:53 +00:00
}
#ifdef MAC
error = mac_vnode_check_unlink(td->td_ucred, nd.ni_dvp, vp,
&nd.ni_cnd);
if (error)
goto out;
#endif
if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(vp);
if (nd.ni_dvp == vp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
VFS_UNLOCK_GIANT(vfslocked);
if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
return (error);
goto restart;
}
error = VOP_RMDIR(nd.ni_dvp, nd.ni_vp, &nd.ni_cnd);
vn_finished_write(mp);
out:
NDFREE(&nd, NDF_ONLY_PNBUF);
vput(vp);
if (nd.ni_dvp == vp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
#ifdef COMPAT_43
/*
2002-05-16 21:28:32 +00:00
* Read a block of directory entries in a filesystem independent format.
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct ogetdirentries_args {
int fd;
char *buf;
u_int count;
long *basep;
};
#endif
int
ogetdirentries(struct thread *td, struct ogetdirentries_args *uap)
{
long loff;
int error;
error = kern_ogetdirentries(td, uap, &loff);
if (error == 0)
error = copyout(&loff, uap->basep, sizeof(long));
return (error);
}
int
kern_ogetdirentries(struct thread *td, struct ogetdirentries_args *uap,
long *ploff)
1994-05-24 10:09:53 +00:00
{
struct vnode *vp;
1994-05-24 10:09:53 +00:00
struct file *fp;
struct uio auio, kuio;
struct iovec aiov, kiov;
struct dirent *dp, *edp;
caddr_t dirbuf;
int error, eofflag, readcnt, vfslocked;
1994-05-24 10:09:53 +00:00
long loff;
/* XXX arbitrary sanity limit on `count'. */
2002-12-14 01:56:26 +00:00
if (uap->count > 64 * 1024)
return (EINVAL);
if ((error = getvnode(td->td_proc->p_fd, uap->fd, CAP_READ,
&fp)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
if ((fp->f_flag & FREAD) == 0) {
fdrop(fp, td);
1994-05-24 10:09:53 +00:00
return (EBADF);
}
vp = fp->f_vnode;
unionread:
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
if (vp->v_type != VDIR) {
VFS_UNLOCK_GIANT(vfslocked);
fdrop(fp, td);
1994-05-24 10:09:53 +00:00
return (EINVAL);
}
2002-12-14 01:56:26 +00:00
aiov.iov_base = uap->buf;
aiov.iov_len = uap->count;
1994-05-24 10:09:53 +00:00
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_rw = UIO_READ;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_td = td;
2002-12-14 01:56:26 +00:00
auio.uio_resid = uap->count;
vn_lock(vp, LK_SHARED | LK_RETRY);
1994-05-24 10:09:53 +00:00
loff = auio.uio_offset = fp->f_offset;
#ifdef MAC
error = mac_vnode_check_readdir(td->td_ucred, vp);
if (error) {
VOP_UNLOCK(vp, 0);
VFS_UNLOCK_GIANT(vfslocked);
fdrop(fp, td);
return (error);
}
#endif
1994-05-24 10:09:53 +00:00
# if (BYTE_ORDER != LITTLE_ENDIAN)
if (vp->v_mount->mnt_maxsymlinklen <= 0) {
error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag,
NULL, NULL);
1994-05-24 10:09:53 +00:00
fp->f_offset = auio.uio_offset;
} else
# endif
{
kuio = auio;
kuio.uio_iov = &kiov;
kuio.uio_segflg = UIO_SYSSPACE;
2002-12-14 01:56:26 +00:00
kiov.iov_len = uap->count;
dirbuf = malloc(uap->count, M_TEMP, M_WAITOK);
1994-05-24 10:09:53 +00:00
kiov.iov_base = dirbuf;
error = VOP_READDIR(vp, &kuio, fp->f_cred, &eofflag,
NULL, NULL);
1994-05-24 10:09:53 +00:00
fp->f_offset = kuio.uio_offset;
if (error == 0) {
2002-12-14 01:56:26 +00:00
readcnt = uap->count - kuio.uio_resid;
1994-05-24 10:09:53 +00:00
edp = (struct dirent *)&dirbuf[readcnt];
for (dp = (struct dirent *)dirbuf; dp < edp; ) {
# if (BYTE_ORDER == LITTLE_ENDIAN)
/*
* The expected low byte of
* dp->d_namlen is our dp->d_type.
* The high MBZ byte of dp->d_namlen
* is our dp->d_namlen.
*/
dp->d_type = dp->d_namlen;
dp->d_namlen = 0;
# else
/*
* The dp->d_type is the high byte
* of the expected dp->d_namlen,
* so must be zero'ed.
*/
dp->d_type = 0;
# endif
if (dp->d_reclen > 0) {
dp = (struct dirent *)
((char *)dp + dp->d_reclen);
} else {
error = EIO;
break;
}
}
if (dp >= edp)
error = uiomove(dirbuf, readcnt, &auio);
}
free(dirbuf, M_TEMP);
1994-05-24 10:09:53 +00:00
}
if (error) {
VOP_UNLOCK(vp, 0);
VFS_UNLOCK_GIANT(vfslocked);
fdrop(fp, td);
1994-05-24 10:09:53 +00:00
return (error);
}
if (uap->count == auio.uio_resid &&
(vp->v_vflag & VV_ROOT) &&
(vp->v_mount->mnt_flag & MNT_UNION)) {
struct vnode *tvp = vp;
vp = vp->v_mount->mnt_vnodecovered;
VREF(vp);
fp->f_vnode = vp;
fp->f_data = vp;
fp->f_offset = 0;
vput(tvp);
VFS_UNLOCK_GIANT(vfslocked);
goto unionread;
}
VOP_UNLOCK(vp, 0);
VFS_UNLOCK_GIANT(vfslocked);
fdrop(fp, td);
2002-12-14 01:56:26 +00:00
td->td_retval[0] = uap->count - auio.uio_resid;
if (error == 0)
*ploff = loff;
1994-05-24 10:09:53 +00:00
return (error);
}
#endif /* COMPAT_43 */
1994-05-24 10:09:53 +00:00
/*
2002-05-16 21:28:32 +00:00
* Read a block of directory entries in a filesystem independent format.
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct getdirentries_args {
int fd;
char *buf;
u_int count;
long *basep;
};
#endif
int
sys_getdirentries(td, uap)
struct thread *td;
register struct getdirentries_args /* {
int fd;
char *buf;
u_int count;
long *basep;
} */ *uap;
{
long base;
int error;
error = kern_getdirentries(td, uap->fd, uap->buf, uap->count, &base);
if (error)
return (error);
if (uap->basep != NULL)
error = copyout(&base, uap->basep, sizeof(long));
return (error);
}
int
kern_getdirentries(struct thread *td, int fd, char *buf, u_int count,
long *basep)
1994-05-24 10:09:53 +00:00
{
struct vnode *vp;
1994-05-24 10:09:53 +00:00
struct file *fp;
struct uio auio;
struct iovec aiov;
int vfslocked;
1994-05-24 10:09:53 +00:00
long loff;
int error, eofflag;
1994-05-24 10:09:53 +00:00
AUDIT_ARG_FD(fd);
if (count > INT_MAX)
return (EINVAL);
if ((error = getvnode(td->td_proc->p_fd, fd, CAP_READ | CAP_SEEK,
&fp)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
if ((fp->f_flag & FREAD) == 0) {
fdrop(fp, td);
1994-05-24 10:09:53 +00:00
return (EBADF);
}
vp = fp->f_vnode;
1994-05-24 10:09:53 +00:00
unionread:
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
if (vp->v_type != VDIR) {
VFS_UNLOCK_GIANT(vfslocked);
error = EINVAL;
goto fail;
}
aiov.iov_base = buf;
aiov.iov_len = count;
1994-05-24 10:09:53 +00:00
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_rw = UIO_READ;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_td = td;
auio.uio_resid = count;
vn_lock(vp, LK_SHARED | LK_RETRY);
AUDIT_ARG_VNODE1(vp);
1994-05-24 10:09:53 +00:00
loff = auio.uio_offset = fp->f_offset;
#ifdef MAC
error = mac_vnode_check_readdir(td->td_ucred, vp);
if (error == 0)
#endif
error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, NULL,
NULL);
1994-05-24 10:09:53 +00:00
fp->f_offset = auio.uio_offset;
if (error) {
VOP_UNLOCK(vp, 0);
VFS_UNLOCK_GIANT(vfslocked);
goto fail;
}
if (count == auio.uio_resid &&
(vp->v_vflag & VV_ROOT) &&
(vp->v_mount->mnt_flag & MNT_UNION)) {
struct vnode *tvp = vp;
vp = vp->v_mount->mnt_vnodecovered;
VREF(vp);
fp->f_vnode = vp;
fp->f_data = vp;
fp->f_offset = 0;
vput(tvp);
VFS_UNLOCK_GIANT(vfslocked);
goto unionread;
}
VOP_UNLOCK(vp, 0);
VFS_UNLOCK_GIANT(vfslocked);
*basep = loff;
td->td_retval[0] = count - auio.uio_resid;
fail:
fdrop(fp, td);
1994-05-24 10:09:53 +00:00
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct getdents_args {
int fd;
char *buf;
size_t count;
};
#endif
int
sys_getdents(td, uap)
struct thread *td;
register struct getdents_args /* {
int fd;
char *buf;
u_int count;
} */ *uap;
{
struct getdirentries_args ap;
ap.fd = uap->fd;
ap.buf = uap->buf;
ap.count = uap->count;
ap.basep = NULL;
return (sys_getdirentries(td, &ap));
}
1994-05-24 10:09:53 +00:00
/*
* Set the mode mask for creation of filesystem nodes.
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct umask_args {
int newmask;
};
#endif
int
sys_umask(td, uap)
struct thread *td;
struct umask_args /* {
int newmask;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
register struct filedesc *fdp;
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XLOCK(td->td_proc->p_fd);
fdp = td->td_proc->p_fd;
td->td_retval[0] = fdp->fd_cmask;
2002-12-14 01:56:26 +00:00
fdp->fd_cmask = uap->newmask & ALLPERMS;
Replace custom file descriptor array sleep lock constructed using a mutex and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
FILEDESC_XUNLOCK(td->td_proc->p_fd);
1994-05-24 10:09:53 +00:00
return (0);
}
/*
* Void all references to file by ripping underlying filesystem away from
* vnode.
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
1994-05-24 10:09:53 +00:00
struct revoke_args {
char *path;
};
#endif
int
sys_revoke(td, uap)
struct thread *td;
register struct revoke_args /* {
char *path;
} */ *uap;
1994-05-24 10:09:53 +00:00
{
struct vnode *vp;
1994-05-24 10:09:53 +00:00
struct vattr vattr;
int error;
struct nameidata nd;
int vfslocked;
1994-05-24 10:09:53 +00:00
NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
UIO_USERSPACE, uap->path, td);
if ((error = namei(&nd)) != 0)
1994-05-24 10:09:53 +00:00
return (error);
vfslocked = NDHASGIANT(&nd);
1994-05-24 10:09:53 +00:00
vp = nd.ni_vp;
NDFREE(&nd, NDF_ONLY_PNBUF);
if (vp->v_type != VCHR || vp->v_rdev == NULL) {
error = EINVAL;
goto out;
}
#ifdef MAC
error = mac_vnode_check_revoke(td->td_ucred, vp);
if (error)
goto out;
#endif
error = VOP_GETATTR(vp, &vattr, td->td_ucred);
if (error)
goto out;
if (td->td_ucred->cr_uid != vattr.va_uid) {
error = priv_check(td, PRIV_VFS_ADMIN);
if (error)
goto out;
}
if (vcount(vp) > 1)
VOP_REVOKE(vp, REVOKEALL);
out:
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
1994-05-24 10:09:53 +00:00
return (error);
}
/*
* Convert a user file descriptor to a kernel file entry and check that, if it
* is a capability, the correct rights are present. A reference on the file
* entry is held upon returning.
1994-05-24 10:09:53 +00:00
*/
int
getvnode(struct filedesc *fdp, int fd, cap_rights_t rights,
struct file **fpp)
1994-05-24 10:09:53 +00:00
{
struct file *fp;
#ifdef CAPABILITIES
struct file *fp_fromcap;
#endif
int error;
1994-05-24 10:09:53 +00:00
error = 0;
fp = NULL;
if ((fdp == NULL) || (fp = fget_unlocked(fdp, fd)) == NULL)
return (EBADF);
#ifdef CAPABILITIES
/*
* If the file descriptor is for a capability, test rights and use the
* file descriptor referenced by the capability.
*/
error = cap_funwrap(fp, rights, &fp_fromcap);
if (error) {
fdrop(fp, curthread);
return (error);
}
if (fp != fp_fromcap) {
fhold(fp_fromcap);
fdrop(fp, curthread);
fp = fp_fromcap;
}
#endif /* CAPABILITIES */
/*
* The file could be not of the vnode type, or it may be not
* yet fully initialized, in which case the f_vnode pointer
* may be set, but f_ops is still badfileops. E.g.,
* devfs_open() transiently create such situation to
* facilitate csw d_fdopen().
*
* Dupfdopen() handling in kern_openat() installs the
* half-baked file into the process descriptor table, allowing
* other thread to dereference it. Guard against the race by
* checking f_ops.
*/
if (fp->f_vnode == NULL || fp->f_ops == &badfileops) {
fdrop(fp, curthread);
return (EINVAL);
}
1994-05-24 10:09:53 +00:00
*fpp = fp;
return (0);
1994-05-24 10:09:53 +00:00
}
/*
* Get an (NFS) file handle.
*/
#ifndef _SYS_SYSPROTO_H_
struct lgetfh_args {
char *fname;
fhandle_t *fhp;
};
#endif
int
sys_lgetfh(td, uap)
struct thread *td;
register struct lgetfh_args *uap;
{
struct nameidata nd;
fhandle_t fh;
register struct vnode *vp;
int vfslocked;
int error;
error = priv_check(td, PRIV_VFS_GETFH);
if (error)
return (error);
NDINIT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
UIO_USERSPACE, uap->fname, td);
error = namei(&nd);
if (error)
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
vp = nd.ni_vp;
bzero(&fh, sizeof(fh));
fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
error = VOP_VPTOFH(vp, &fh.fh_fid);
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
if (error)
return (error);
error = copyout(&fh, uap->fhp, sizeof (fh));
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct getfh_args {
char *fname;
fhandle_t *fhp;
};
#endif
int
sys_getfh(td, uap)
struct thread *td;
register struct getfh_args *uap;
{
struct nameidata nd;
fhandle_t fh;
register struct vnode *vp;
int vfslocked;
int error;
error = priv_check(td, PRIV_VFS_GETFH);
if (error)
return (error);
NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
UIO_USERSPACE, uap->fname, td);
error = namei(&nd);
if (error)
return (error);
vfslocked = NDHASGIANT(&nd);
NDFREE(&nd, NDF_ONLY_PNBUF);
vp = nd.ni_vp;
bzero(&fh, sizeof(fh));
fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
error = VOP_VPTOFH(vp, &fh.fh_fid);
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
if (error)
return (error);
error = copyout(&fh, uap->fhp, sizeof (fh));
return (error);
}
/*
* syscall for the rpc.lockd to use to translate a NFS file handle into an
* open descriptor.
*
* warning: do not remove the priv_check() call or this becomes one giant
* security hole.
*/
#ifndef _SYS_SYSPROTO_H_
struct fhopen_args {
const struct fhandle *u_fhp;
int flags;
};
#endif
int
sys_fhopen(td, uap)
struct thread *td;
struct fhopen_args /* {
const struct fhandle *u_fhp;
int flags;
} */ *uap;
{
struct proc *p = td->td_proc;
struct mount *mp;
struct vnode *vp;
struct fhandle fhp;
struct vattr vat;
struct vattr *vap = &vat;
struct flock lf;
struct file *fp;
register struct filedesc *fdp = p->p_fd;
int fmode, error, type;
accmode_t accmode;
struct file *nfp;
int vfslocked;
int indx;
error = priv_check(td, PRIV_VFS_FHOPEN);
if (error)
return (error);
2002-12-14 01:56:26 +00:00
fmode = FFLAGS(uap->flags);
/* why not allow a non-read/write open for our lockd? */
if (((fmode & (FREAD | FWRITE)) == 0) || (fmode & O_CREAT))
return (EINVAL);
2002-12-14 01:56:26 +00:00
error = copyin(uap->u_fhp, &fhp, sizeof(fhp));
if (error)
return(error);
/* find the mount point */
mp = vfs_busyfs(&fhp.fh_fsid);
if (mp == NULL)
return (ESTALE);
vfslocked = VFS_LOCK_GIANT(mp);
/* now give me my vnode, it gets returned to me locked */
error = VFS_FHTOVP(mp, &fhp.fh_fid, LK_EXCLUSIVE, &vp);
vfs_unbusy(mp);
if (error)
goto out;
/*
* from now on we have to make sure not
* to forget about the vnode
* any error that causes an abort must vput(vp)
* just set error = err and 'goto bad;'.
*/
/*
* from vn_open
*/
if (vp->v_type == VLNK) {
error = EMLINK;
goto bad;
}
if (vp->v_type == VSOCK) {
error = EOPNOTSUPP;
goto bad;
}
if (vp->v_type != VDIR && fmode & O_DIRECTORY) {
error = ENOTDIR;
goto bad;
}
accmode = 0;
if (fmode & (FWRITE | O_TRUNC)) {
if (vp->v_type == VDIR) {
error = EISDIR;
goto bad;
}
error = vn_writechk(vp);
if (error)
goto bad;
accmode |= VWRITE;
}
if (fmode & FREAD)
accmode |= VREAD;
if ((fmode & O_APPEND) && (fmode & FWRITE))
accmode |= VAPPEND;
#ifdef MAC
error = mac_vnode_check_open(td->td_ucred, vp, accmode);
if (error)
goto bad;
#endif
if (accmode) {
error = VOP_ACCESS(vp, accmode, td->td_ucred, td);
if (error)
goto bad;
}
if (fmode & O_TRUNC) {
vfs_ref(mp);
VOP_UNLOCK(vp, 0); /* XXX */
if ((error = vn_start_write(NULL, &mp, V_WAIT | PCATCH)) != 0) {
vrele(vp);
vfs_rel(mp);
goto out;
}
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */
vfs_rel(mp);
#ifdef MAC
/*
* We don't yet have fp->f_cred, so use td->td_ucred, which
* should be right.
*/
error = mac_vnode_check_write(td->td_ucred, td->td_ucred, vp);
if (error == 0) {
#endif
VATTR_NULL(vap);
vap->va_size = 0;
error = VOP_SETATTR(vp, vap, td->td_ucred);
#ifdef MAC
}
#endif
vn_finished_write(mp);
if (error)
goto bad;
}
error = VOP_OPEN(vp, fmode, td->td_ucred, td, NULL);
if (error)
goto bad;
if (fmode & FWRITE)
vp->v_writecount++;
/*
* end of vn_open code
*/
if ((error = falloc(td, &nfp, &indx, fmode)) != 0) {
if (fmode & FWRITE)
vp->v_writecount--;
goto bad;
}
/* An extra reference on `nfp' has been held for us by falloc(). */
fp = nfp;
nfp->f_vnode = vp;
finit(nfp, fmode & FMASK, DTYPE_VNODE, vp, &vnops);
if (fmode & (O_EXLOCK | O_SHLOCK)) {
lf.l_whence = SEEK_SET;
lf.l_start = 0;
lf.l_len = 0;
if (fmode & O_EXLOCK)
lf.l_type = F_WRLCK;
else
lf.l_type = F_RDLCK;
type = F_FLOCK;
if ((fmode & FNONBLOCK) == 0)
type |= F_WAIT;
VOP_UNLOCK(vp, 0);
2002-06-28 23:02:38 +00:00
if ((error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
type)) != 0) {
/*
* The lock request failed. Normally close the
* descriptor but handle the case where someone might
* have dup()d or close()d it when we weren't looking.
*/
fdclose(fdp, fp, indx, td);
/*
* release our private reference
*/
fdrop(fp, td);
goto out;
}
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
atomic_set_int(&fp->f_flag, FHASLOCK);
}
VOP_UNLOCK(vp, 0);
fdrop(fp, td);
VFS_UNLOCK_GIANT(vfslocked);
td->td_retval[0] = indx;
return (0);
bad:
vput(vp);
out:
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
/*
* Stat an (NFS) file handle.
*/
#ifndef _SYS_SYSPROTO_H_
struct fhstat_args {
struct fhandle *u_fhp;
struct stat *sb;
};
#endif
int
sys_fhstat(td, uap)
struct thread *td;
register struct fhstat_args /* {
struct fhandle *u_fhp;
struct stat *sb;
} */ *uap;
{
struct stat sb;
fhandle_t fh;
struct mount *mp;
struct vnode *vp;
int vfslocked;
int error;
error = priv_check(td, PRIV_VFS_FHSTAT);
if (error)
return (error);
2002-12-14 01:56:26 +00:00
error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
if (error)
return (error);
if ((mp = vfs_busyfs(&fh.fh_fsid)) == NULL)
return (ESTALE);
vfslocked = VFS_LOCK_GIANT(mp);
error = VFS_FHTOVP(mp, &fh.fh_fid, LK_EXCLUSIVE, &vp);
vfs_unbusy(mp);
if (error) {
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
Make similar changes to fo_stat() and fo_poll() as made earlier to fo_read() and fo_write(): explicitly use the cred argument to fo_poll() as "active_cred" using the passed file descriptor's f_cred reference to provide access to the file credential. Add an active_cred argument to fo_stat() so that implementers have access to the active credential as well as the file credential. Generally modify callers of fo_stat() to pass in td->td_ucred rather than fp->f_cred, which was redundantly provided via the fp argument. This set of modifications also permits threads to perform these operations on behalf of another thread without modifying their credential. Trickle this change down into fo_stat/poll() implementations: - badfo_poll(), badfo_stat(): modify/add arguments. - kqueue_poll(), kqueue_stat(): modify arguments. - pipe_poll(), pipe_stat(): modify/add arguments, pass active_cred to MAC checks rather than td->td_ucred. - soo_poll(), soo_stat(): modify/add arguments, pass fp->f_cred rather than cred to pru_sopoll() to maintain current semantics. - sopoll(): moidfy arguments. - vn_poll(), vn_statfile(): modify/add arguments, pass new arguments to vn_stat(). Pass active_cred to MAC and fp->f_cred to VOP_POLL() to maintian current semantics. - vn_close(): rename cred to file_cred to reflect reality while I'm here. - vn_stat(): Add active_cred and file_cred arguments to vn_stat() and consumers so that this distinction is maintained at the VFS as well as 'struct file' layer. Pass active_cred instead of td->td_ucred to MAC and to VOP_GETATTR() to maintain current semantics. - fifofs: modify the creation of a "filetemp" so that the file credential is properly initialized and can be used in the socket code if desired. Pass ap->a_td->td_ucred as the active credential to soo_poll(). If we teach the vnop interface about the distinction between file and active credentials, we would use the active credential here. Note that current inconsistent passing of active_cred vs. file_cred to VOP's is maintained. It's not clear why GETATTR would be authorized using active_cred while POLL would be authorized using file_cred at the file system level. Obtained from: TrustedBSD Project Sponsored by: DARPA, NAI Labs
2002-08-16 12:52:03 +00:00
error = vn_stat(vp, &sb, td->td_ucred, NOCRED, td);
vput(vp);
VFS_UNLOCK_GIANT(vfslocked);
if (error)
return (error);
2002-12-14 01:56:26 +00:00
error = copyout(&sb, uap->sb, sizeof(sb));
return (error);
}
/*
* Implement fstatfs() for (NFS) file handles.
*/
#ifndef _SYS_SYSPROTO_H_
struct fhstatfs_args {
struct fhandle *u_fhp;
struct statfs *buf;
};
#endif
int
sys_fhstatfs(td, uap)
struct thread *td;
struct fhstatfs_args /* {
struct fhandle *u_fhp;
struct statfs *buf;
} */ *uap;
{
struct statfs sf;
fhandle_t fh;
int error;
error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
if (error)
return (error);
error = kern_fhstatfs(td, fh, &sf);
if (error)
return (error);
return (copyout(&sf, uap->buf, sizeof(sf)));
}
int
kern_fhstatfs(struct thread *td, fhandle_t fh, struct statfs *buf)
{
struct statfs *sp;
struct mount *mp;
struct vnode *vp;
int vfslocked;
int error;
error = priv_check(td, PRIV_VFS_FHSTATFS);
if (error)
return (error);
if ((mp = vfs_busyfs(&fh.fh_fsid)) == NULL)
return (ESTALE);
vfslocked = VFS_LOCK_GIANT(mp);
error = VFS_FHTOVP(mp, &fh.fh_fid, LK_EXCLUSIVE, &vp);
if (error) {
vfs_unbusy(mp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
vput(vp);
error = prison_canseemount(td->td_ucred, mp);
if (error)
goto out;
#ifdef MAC
error = mac_mount_check_stat(td->td_ucred, mp);
if (error)
goto out;
#endif
/*
* Set these in case the underlying filesystem fails to do so.
*/
sp = &mp->mnt_stat;
sp->f_version = STATFS_VERSION;
sp->f_namemax = NAME_MAX;
sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
error = VFS_STATFS(mp, sp);
if (error == 0)
*buf = *sp;
out:
vfs_unbusy(mp);
VFS_UNLOCK_GIANT(vfslocked);
return (error);
}
int
kern_posix_fallocate(struct thread *td, int fd, off_t offset, off_t len)
{
struct file *fp;
struct mount *mp;
struct vnode *vp;
off_t olen, ooffset;
int error, vfslocked;
fp = NULL;
vfslocked = 0;
error = fget(td, fd, CAP_WRITE, &fp);
if (error != 0)
goto out;
switch (fp->f_type) {
case DTYPE_VNODE:
break;
case DTYPE_PIPE:
case DTYPE_FIFO:
error = ESPIPE;
goto out;
default:
error = ENODEV;
goto out;
}
2011-04-18 16:40:47 +00:00
if ((fp->f_flag & FWRITE) == 0) {
error = EBADF;
goto out;
2011-04-18 16:40:47 +00:00
}
vp = fp->f_vnode;
if (vp->v_type != VREG) {
error = ENODEV;
goto out;
}
if (offset < 0 || len <= 0) {
error = EINVAL;
goto out;
}
/* Check for wrap. */
if (offset > OFF_MAX - len) {
error = EFBIG;
goto out;
}
/* Allocating blocks may take a long time, so iterate. */
for (;;) {
olen = len;
ooffset = offset;
bwillwrite();
vfslocked = VFS_LOCK_GIANT(vp->v_mount);
mp = NULL;
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
if (error != 0) {
VFS_UNLOCK_GIANT(vfslocked);
break;
}
error = vn_lock(vp, LK_EXCLUSIVE);
if (error != 0) {
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
break;
}
#ifdef MAC
error = mac_vnode_check_write(td->td_ucred, fp->f_cred, vp);
if (error == 0)
#endif
error = VOP_ALLOCATE(vp, &offset, &len);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
VFS_UNLOCK_GIANT(vfslocked);
if (olen + ooffset != offset + len) {
panic("offset + len changed from %jx/%jx to %jx/%jx",
ooffset, olen, offset, len);
}
if (error != 0 || len == 0)
break;
KASSERT(olen > len, ("Iteration did not make progress?"));
maybe_yield();
}
out:
if (fp != NULL)
fdrop(fp, td);
return (error);
}
int
sys_posix_fallocate(struct thread *td, struct posix_fallocate_args *uap)
{
return (kern_posix_fallocate(td, uap->fd, uap->offset, uap->len));
}
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
/*
* Unlike madvise(2), we do not make a best effort to remember every
* possible caching hint. Instead, we remember the last setting with
* the exception that we will allow POSIX_FADV_NORMAL to adjust the
* region of any current setting.
*/
int
kern_posix_fadvise(struct thread *td, int fd, off_t offset, off_t len,
int advice)
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
{
struct fadvise_info *fa, *new;
struct file *fp;
struct vnode *vp;
off_t end;
int error;
if (offset < 0 || len < 0 || offset > OFF_MAX - len)
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
return (EINVAL);
switch (advice) {
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
case POSIX_FADV_SEQUENTIAL:
case POSIX_FADV_RANDOM:
case POSIX_FADV_NOREUSE:
new = malloc(sizeof(*fa), M_FADVISE, M_WAITOK);
break;
case POSIX_FADV_NORMAL:
case POSIX_FADV_WILLNEED:
case POSIX_FADV_DONTNEED:
new = NULL;
break;
default:
return (EINVAL);
}
/* XXX: CAP_POSIX_FADVISE? */
error = fget(td, fd, 0, &fp);
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
if (error != 0)
goto out;
switch (fp->f_type) {
case DTYPE_VNODE:
break;
case DTYPE_PIPE:
case DTYPE_FIFO:
error = ESPIPE;
goto out;
default:
error = ENODEV;
goto out;
}
vp = fp->f_vnode;
if (vp->v_type != VREG) {
error = ENODEV;
goto out;
}
if (len == 0)
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
end = OFF_MAX;
else
end = offset + len - 1;
switch (advice) {
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
case POSIX_FADV_SEQUENTIAL:
case POSIX_FADV_RANDOM:
case POSIX_FADV_NOREUSE:
/*
* Try to merge any existing non-standard region with
* this new region if possible, otherwise create a new
* non-standard region for this request.
*/
mtx_pool_lock(mtxpool_sleep, fp);
fa = fp->f_advice;
if (fa != NULL && fa->fa_advice == advice &&
((fa->fa_start <= end && fa->fa_end >= offset) ||
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
(end != OFF_MAX && fa->fa_start == end + 1) ||
(fa->fa_end != OFF_MAX && fa->fa_end + 1 == offset))) {
if (offset < fa->fa_start)
fa->fa_start = offset;
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
if (end > fa->fa_end)
fa->fa_end = end;
} else {
new->fa_advice = advice;
new->fa_start = offset;
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
new->fa_end = end;
fp->f_advice = new;
new = fa;
}
mtx_pool_unlock(mtxpool_sleep, fp);
break;
case POSIX_FADV_NORMAL:
/*
* If a the "normal" region overlaps with an existing
* non-standard region, trim or remove the
* non-standard region.
*/
mtx_pool_lock(mtxpool_sleep, fp);
fa = fp->f_advice;
if (fa != NULL) {
if (offset <= fa->fa_start && end >= fa->fa_end) {
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
new = fa;
fp->f_advice = NULL;
} else if (offset <= fa->fa_start &&
end >= fa->fa_start)
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
fa->fa_start = end + 1;
else if (offset <= fa->fa_end && end >= fa->fa_end)
fa->fa_end = offset - 1;
else if (offset >= fa->fa_start && end <= fa->fa_end) {
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
/*
* If the "normal" region is a middle
* portion of the existing
* non-standard region, just remove
* the whole thing rather than picking
* one side or the other to
* preserve.
*/
new = fa;
fp->f_advice = NULL;
}
}
mtx_pool_unlock(mtxpool_sleep, fp);
break;
case POSIX_FADV_WILLNEED:
case POSIX_FADV_DONTNEED:
error = VOP_ADVISE(vp, offset, end, advice);
Add the posix_fadvise(2) system call. It is somewhat similar to madvise(2) except that it operates on a file descriptor instead of a memory region. It is currently only supported on regular files. Just as with madvise(2), the advice given to posix_fadvise(2) can be divided into two types. The first type provide hints about data access patterns and are used in the file read and write routines to modify the I/O flags passed down to VOP_READ() and VOP_WRITE(). These modes are thus filesystem independent. Note that to ease implementation (and since this API is only advisory anyway), only a single non-normal range is allowed per file descriptor. The second type of hints are used to hint to the OS that data will or will not be used. These hints are implemented via a new VOP_ADVISE(). A default implementation is provided which does nothing for the WILLNEED request and attempts to move any clean pages to the cache page queue for the DONTNEED request. This latter case required two other changes. First, a new V_CLEANONLY flag was added to vinvalbuf(). This requests vinvalbuf() to only flush clean buffers for the vnode from the buffer cache and to not remove any backing pages from the vnode. This is used to ensure clean pages are not wired into the buffer cache before attempting to move them to the cache page queue. The second change adds a new vm_object_page_cache() method. This method is somewhat similar to vm_object_page_remove() except that instead of freeing each page in the specified range, it attempts to move clean pages to the cache queue if possible. To preserve the ABI of struct file, the f_cdevpriv pointer is now reused in a union to point to the currently active advice region if one is present for regular files. Reviewed by: jilles, kib, arch@ Approved by: re (kib) MFC after: 1 month
2011-11-04 04:02:50 +00:00
break;
}
out:
if (fp != NULL)
fdrop(fp, td);
free(new, M_FADVISE);
return (error);
}
int
sys_posix_fadvise(struct thread *td, struct posix_fadvise_args *uap)
{
return (kern_posix_fadvise(td, uap->fd, uap->offset, uap->len,
uap->advice));
}