7e14088d93
is chunked to pieces limited by integer io_hold_cnt tunable, while vm_fault_quick_hold_pages() takes integer max_count as the upper bound. Rearrange the checks to correctly handle overflowing address arithmetic. Submitted by: bde Tested by: pho Discussed with: alc MFC after: 1 week
2085 lines
52 KiB
C
2085 lines
52 KiB
C
/*-
|
|
* Copyright (c) 1982, 1986, 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.
|
|
*
|
|
* Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
|
|
* Copyright (c) 2013 The FreeBSD Foundation
|
|
*
|
|
* Portions of this software were developed by Konstantin Belousov
|
|
* under sponsorship from the FreeBSD Foundation.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
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|
* 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_vnops.c 8.2 (Berkeley) 1/21/94
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/disk.h>
|
|
#include <sys/fcntl.h>
|
|
#include <sys/file.h>
|
|
#include <sys/kdb.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/priv.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/limits.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mount.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/namei.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/bio.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/filio.h>
|
|
#include <sys/resourcevar.h>
|
|
#include <sys/rwlock.h>
|
|
#include <sys/sx.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/ttycom.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/syslog.h>
|
|
#include <sys/unistd.h>
|
|
|
|
#include <security/audit/audit.h>
|
|
#include <security/mac/mac_framework.h>
|
|
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_extern.h>
|
|
#include <vm/pmap.h>
|
|
#include <vm/vm_map.h>
|
|
#include <vm/vm_object.h>
|
|
#include <vm/vm_page.h>
|
|
|
|
static fo_rdwr_t vn_read;
|
|
static fo_rdwr_t vn_write;
|
|
static fo_rdwr_t vn_io_fault;
|
|
static fo_truncate_t vn_truncate;
|
|
static fo_ioctl_t vn_ioctl;
|
|
static fo_poll_t vn_poll;
|
|
static fo_kqfilter_t vn_kqfilter;
|
|
static fo_stat_t vn_statfile;
|
|
static fo_close_t vn_closefile;
|
|
|
|
struct fileops vnops = {
|
|
.fo_read = vn_io_fault,
|
|
.fo_write = vn_io_fault,
|
|
.fo_truncate = vn_truncate,
|
|
.fo_ioctl = vn_ioctl,
|
|
.fo_poll = vn_poll,
|
|
.fo_kqfilter = vn_kqfilter,
|
|
.fo_stat = vn_statfile,
|
|
.fo_close = vn_closefile,
|
|
.fo_chmod = vn_chmod,
|
|
.fo_chown = vn_chown,
|
|
.fo_sendfile = vn_sendfile,
|
|
.fo_seek = vn_seek,
|
|
.fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE
|
|
};
|
|
|
|
int
|
|
vn_open(ndp, flagp, cmode, fp)
|
|
struct nameidata *ndp;
|
|
int *flagp, cmode;
|
|
struct file *fp;
|
|
{
|
|
struct thread *td = ndp->ni_cnd.cn_thread;
|
|
|
|
return (vn_open_cred(ndp, flagp, cmode, 0, td->td_ucred, fp));
|
|
}
|
|
|
|
/*
|
|
* Common code for vnode open operations via a name lookup.
|
|
* Lookup the vnode and invoke VOP_CREATE if needed.
|
|
* Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
|
|
*
|
|
* Note that this does NOT free nameidata for the successful case,
|
|
* due to the NDINIT being done elsewhere.
|
|
*/
|
|
int
|
|
vn_open_cred(struct nameidata *ndp, int *flagp, int cmode, u_int vn_open_flags,
|
|
struct ucred *cred, struct file *fp)
|
|
{
|
|
struct vnode *vp;
|
|
struct mount *mp;
|
|
struct thread *td = ndp->ni_cnd.cn_thread;
|
|
struct vattr vat;
|
|
struct vattr *vap = &vat;
|
|
int fmode, error;
|
|
|
|
restart:
|
|
fmode = *flagp;
|
|
if (fmode & O_CREAT) {
|
|
ndp->ni_cnd.cn_nameiop = CREATE;
|
|
ndp->ni_cnd.cn_flags = ISOPEN | LOCKPARENT | LOCKLEAF;
|
|
if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
|
|
ndp->ni_cnd.cn_flags |= FOLLOW;
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|
if (!(vn_open_flags & VN_OPEN_NOAUDIT))
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|
ndp->ni_cnd.cn_flags |= AUDITVNODE1;
|
|
if (vn_open_flags & VN_OPEN_NOCAPCHECK)
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|
ndp->ni_cnd.cn_flags |= NOCAPCHECK;
|
|
bwillwrite();
|
|
if ((error = namei(ndp)) != 0)
|
|
return (error);
|
|
if (ndp->ni_vp == NULL) {
|
|
VATTR_NULL(vap);
|
|
vap->va_type = VREG;
|
|
vap->va_mode = cmode;
|
|
if (fmode & O_EXCL)
|
|
vap->va_vaflags |= VA_EXCLUSIVE;
|
|
if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) {
|
|
NDFREE(ndp, NDF_ONLY_PNBUF);
|
|
vput(ndp->ni_dvp);
|
|
if ((error = vn_start_write(NULL, &mp,
|
|
V_XSLEEP | PCATCH)) != 0)
|
|
return (error);
|
|
goto restart;
|
|
}
|
|
#ifdef MAC
|
|
error = mac_vnode_check_create(cred, ndp->ni_dvp,
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|
&ndp->ni_cnd, vap);
|
|
if (error == 0)
|
|
#endif
|
|
error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
|
|
&ndp->ni_cnd, vap);
|
|
vput(ndp->ni_dvp);
|
|
vn_finished_write(mp);
|
|
if (error) {
|
|
NDFREE(ndp, NDF_ONLY_PNBUF);
|
|
return (error);
|
|
}
|
|
fmode &= ~O_TRUNC;
|
|
vp = ndp->ni_vp;
|
|
} else {
|
|
if (ndp->ni_dvp == ndp->ni_vp)
|
|
vrele(ndp->ni_dvp);
|
|
else
|
|
vput(ndp->ni_dvp);
|
|
ndp->ni_dvp = NULL;
|
|
vp = ndp->ni_vp;
|
|
if (fmode & O_EXCL) {
|
|
error = EEXIST;
|
|
goto bad;
|
|
}
|
|
fmode &= ~O_CREAT;
|
|
}
|
|
} else {
|
|
ndp->ni_cnd.cn_nameiop = LOOKUP;
|
|
ndp->ni_cnd.cn_flags = ISOPEN |
|
|
((fmode & O_NOFOLLOW) ? NOFOLLOW : FOLLOW) | LOCKLEAF;
|
|
if (!(fmode & FWRITE))
|
|
ndp->ni_cnd.cn_flags |= LOCKSHARED;
|
|
if (!(vn_open_flags & VN_OPEN_NOAUDIT))
|
|
ndp->ni_cnd.cn_flags |= AUDITVNODE1;
|
|
if (vn_open_flags & VN_OPEN_NOCAPCHECK)
|
|
ndp->ni_cnd.cn_flags |= NOCAPCHECK;
|
|
if ((error = namei(ndp)) != 0)
|
|
return (error);
|
|
vp = ndp->ni_vp;
|
|
}
|
|
error = vn_open_vnode(vp, fmode, cred, td, fp);
|
|
if (error)
|
|
goto bad;
|
|
*flagp = fmode;
|
|
return (0);
|
|
bad:
|
|
NDFREE(ndp, NDF_ONLY_PNBUF);
|
|
vput(vp);
|
|
*flagp = fmode;
|
|
ndp->ni_vp = NULL;
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Common code for vnode open operations once a vnode is located.
|
|
* Check permissions, and call the VOP_OPEN routine.
|
|
*/
|
|
int
|
|
vn_open_vnode(struct vnode *vp, int fmode, struct ucred *cred,
|
|
struct thread *td, struct file *fp)
|
|
{
|
|
struct mount *mp;
|
|
accmode_t accmode;
|
|
struct flock lf;
|
|
int error, have_flock, lock_flags, type;
|
|
|
|
if (vp->v_type == VLNK)
|
|
return (EMLINK);
|
|
if (vp->v_type == VSOCK)
|
|
return (EOPNOTSUPP);
|
|
if (vp->v_type != VDIR && fmode & O_DIRECTORY)
|
|
return (ENOTDIR);
|
|
accmode = 0;
|
|
if (fmode & (FWRITE | O_TRUNC)) {
|
|
if (vp->v_type == VDIR)
|
|
return (EISDIR);
|
|
accmode |= VWRITE;
|
|
}
|
|
if (fmode & FREAD)
|
|
accmode |= VREAD;
|
|
if (fmode & FEXEC)
|
|
accmode |= VEXEC;
|
|
if ((fmode & O_APPEND) && (fmode & FWRITE))
|
|
accmode |= VAPPEND;
|
|
#ifdef MAC
|
|
error = mac_vnode_check_open(cred, vp, accmode);
|
|
if (error)
|
|
return (error);
|
|
#endif
|
|
if ((fmode & O_CREAT) == 0) {
|
|
if (accmode & VWRITE) {
|
|
error = vn_writechk(vp);
|
|
if (error)
|
|
return (error);
|
|
}
|
|
if (accmode) {
|
|
error = VOP_ACCESS(vp, accmode, cred, td);
|
|
if (error)
|
|
return (error);
|
|
}
|
|
}
|
|
if (vp->v_type == VFIFO && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
|
|
vn_lock(vp, LK_UPGRADE | LK_RETRY);
|
|
if ((error = VOP_OPEN(vp, fmode, cred, td, fp)) != 0)
|
|
return (error);
|
|
|
|
if (fmode & (O_EXLOCK | O_SHLOCK)) {
|
|
KASSERT(fp != NULL, ("open with flock requires fp"));
|
|
lock_flags = VOP_ISLOCKED(vp);
|
|
VOP_UNLOCK(vp, 0);
|
|
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;
|
|
error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type);
|
|
have_flock = (error == 0);
|
|
vn_lock(vp, lock_flags | LK_RETRY);
|
|
if (error == 0 && vp->v_iflag & VI_DOOMED)
|
|
error = ENOENT;
|
|
/*
|
|
* Another thread might have used this vnode as an
|
|
* executable while the vnode lock was dropped.
|
|
* Ensure the vnode is still able to be opened for
|
|
* writing after the lock has been obtained.
|
|
*/
|
|
if (error == 0 && accmode & VWRITE)
|
|
error = vn_writechk(vp);
|
|
if (error) {
|
|
VOP_UNLOCK(vp, 0);
|
|
if (have_flock) {
|
|
lf.l_whence = SEEK_SET;
|
|
lf.l_start = 0;
|
|
lf.l_len = 0;
|
|
lf.l_type = F_UNLCK;
|
|
(void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf,
|
|
F_FLOCK);
|
|
}
|
|
vn_start_write(vp, &mp, V_WAIT);
|
|
vn_lock(vp, lock_flags | LK_RETRY);
|
|
(void)VOP_CLOSE(vp, fmode, cred, td);
|
|
vn_finished_write(mp);
|
|
return (error);
|
|
}
|
|
fp->f_flag |= FHASLOCK;
|
|
}
|
|
if (fmode & FWRITE) {
|
|
VOP_ADD_WRITECOUNT(vp, 1);
|
|
CTR3(KTR_VFS, "%s: vp %p v_writecount increased to %d",
|
|
__func__, vp, vp->v_writecount);
|
|
}
|
|
ASSERT_VOP_LOCKED(vp, "vn_open_vnode");
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Check for write permissions on the specified vnode.
|
|
* Prototype text segments cannot be written.
|
|
*/
|
|
int
|
|
vn_writechk(vp)
|
|
register struct vnode *vp;
|
|
{
|
|
|
|
ASSERT_VOP_LOCKED(vp, "vn_writechk");
|
|
/*
|
|
* If there's shared text associated with
|
|
* the vnode, try to free it up once. If
|
|
* we fail, we can't allow writing.
|
|
*/
|
|
if (VOP_IS_TEXT(vp))
|
|
return (ETXTBSY);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Vnode close call
|
|
*/
|
|
int
|
|
vn_close(vp, flags, file_cred, td)
|
|
register struct vnode *vp;
|
|
int flags;
|
|
struct ucred *file_cred;
|
|
struct thread *td;
|
|
{
|
|
struct mount *mp;
|
|
int error, lock_flags;
|
|
|
|
if (vp->v_type != VFIFO && (flags & FWRITE) == 0 &&
|
|
MNT_EXTENDED_SHARED(vp->v_mount))
|
|
lock_flags = LK_SHARED;
|
|
else
|
|
lock_flags = LK_EXCLUSIVE;
|
|
|
|
vn_start_write(vp, &mp, V_WAIT);
|
|
vn_lock(vp, lock_flags | LK_RETRY);
|
|
if (flags & FWRITE) {
|
|
VNASSERT(vp->v_writecount > 0, vp,
|
|
("vn_close: negative writecount"));
|
|
VOP_ADD_WRITECOUNT(vp, -1);
|
|
CTR3(KTR_VFS, "%s: vp %p v_writecount decreased to %d",
|
|
__func__, vp, vp->v_writecount);
|
|
}
|
|
error = VOP_CLOSE(vp, flags, file_cred, td);
|
|
vput(vp);
|
|
vn_finished_write(mp);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Heuristic to detect sequential operation.
|
|
*/
|
|
static int
|
|
sequential_heuristic(struct uio *uio, struct file *fp)
|
|
{
|
|
|
|
if (atomic_load_acq_int(&(fp->f_flag)) & FRDAHEAD)
|
|
return (fp->f_seqcount << IO_SEQSHIFT);
|
|
|
|
/*
|
|
* Offset 0 is handled specially. open() sets f_seqcount to 1 so
|
|
* that the first I/O is normally considered to be slightly
|
|
* sequential. Seeking to offset 0 doesn't change sequentiality
|
|
* unless previous seeks have reduced f_seqcount to 0, in which
|
|
* case offset 0 is not special.
|
|
*/
|
|
if ((uio->uio_offset == 0 && fp->f_seqcount > 0) ||
|
|
uio->uio_offset == fp->f_nextoff) {
|
|
/*
|
|
* f_seqcount is in units of fixed-size blocks so that it
|
|
* depends mainly on the amount of sequential I/O and not
|
|
* much on the number of sequential I/O's. The fixed size
|
|
* of 16384 is hard-coded here since it is (not quite) just
|
|
* a magic size that works well here. This size is more
|
|
* closely related to the best I/O size for real disks than
|
|
* to any block size used by software.
|
|
*/
|
|
fp->f_seqcount += howmany(uio->uio_resid, 16384);
|
|
if (fp->f_seqcount > IO_SEQMAX)
|
|
fp->f_seqcount = IO_SEQMAX;
|
|
return (fp->f_seqcount << IO_SEQSHIFT);
|
|
}
|
|
|
|
/* Not sequential. Quickly draw-down sequentiality. */
|
|
if (fp->f_seqcount > 1)
|
|
fp->f_seqcount = 1;
|
|
else
|
|
fp->f_seqcount = 0;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Package up an I/O request on a vnode into a uio and do it.
|
|
*/
|
|
int
|
|
vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset,
|
|
enum uio_seg segflg, int ioflg, struct ucred *active_cred,
|
|
struct ucred *file_cred, ssize_t *aresid, struct thread *td)
|
|
{
|
|
struct uio auio;
|
|
struct iovec aiov;
|
|
struct mount *mp;
|
|
struct ucred *cred;
|
|
void *rl_cookie;
|
|
int error, lock_flags;
|
|
|
|
auio.uio_iov = &aiov;
|
|
auio.uio_iovcnt = 1;
|
|
aiov.iov_base = base;
|
|
aiov.iov_len = len;
|
|
auio.uio_resid = len;
|
|
auio.uio_offset = offset;
|
|
auio.uio_segflg = segflg;
|
|
auio.uio_rw = rw;
|
|
auio.uio_td = td;
|
|
error = 0;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
if (rw == UIO_READ) {
|
|
rl_cookie = vn_rangelock_rlock(vp, offset,
|
|
offset + len);
|
|
} else {
|
|
rl_cookie = vn_rangelock_wlock(vp, offset,
|
|
offset + len);
|
|
}
|
|
mp = NULL;
|
|
if (rw == UIO_WRITE) {
|
|
if (vp->v_type != VCHR &&
|
|
(error = vn_start_write(vp, &mp, V_WAIT | PCATCH))
|
|
!= 0)
|
|
goto out;
|
|
if (MNT_SHARED_WRITES(mp) ||
|
|
((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount)))
|
|
lock_flags = LK_SHARED;
|
|
else
|
|
lock_flags = LK_EXCLUSIVE;
|
|
} else
|
|
lock_flags = LK_SHARED;
|
|
vn_lock(vp, lock_flags | LK_RETRY);
|
|
} else
|
|
rl_cookie = NULL;
|
|
|
|
ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
|
|
#ifdef MAC
|
|
if ((ioflg & IO_NOMACCHECK) == 0) {
|
|
if (rw == UIO_READ)
|
|
error = mac_vnode_check_read(active_cred, file_cred,
|
|
vp);
|
|
else
|
|
error = mac_vnode_check_write(active_cred, file_cred,
|
|
vp);
|
|
}
|
|
#endif
|
|
if (error == 0) {
|
|
if (file_cred != NULL)
|
|
cred = file_cred;
|
|
else
|
|
cred = active_cred;
|
|
if (rw == UIO_READ)
|
|
error = VOP_READ(vp, &auio, ioflg, cred);
|
|
else
|
|
error = VOP_WRITE(vp, &auio, ioflg, cred);
|
|
}
|
|
if (aresid)
|
|
*aresid = auio.uio_resid;
|
|
else
|
|
if (auio.uio_resid && error == 0)
|
|
error = EIO;
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
VOP_UNLOCK(vp, 0);
|
|
if (mp != NULL)
|
|
vn_finished_write(mp);
|
|
}
|
|
out:
|
|
if (rl_cookie != NULL)
|
|
vn_rangelock_unlock(vp, rl_cookie);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Package up an I/O request on a vnode into a uio and do it. The I/O
|
|
* request is split up into smaller chunks and we try to avoid saturating
|
|
* the buffer cache while potentially holding a vnode locked, so we
|
|
* check bwillwrite() before calling vn_rdwr(). We also call kern_yield()
|
|
* to give other processes a chance to lock the vnode (either other processes
|
|
* core'ing the same binary, or unrelated processes scanning the directory).
|
|
*/
|
|
int
|
|
vn_rdwr_inchunks(rw, vp, base, len, offset, segflg, ioflg, active_cred,
|
|
file_cred, aresid, td)
|
|
enum uio_rw rw;
|
|
struct vnode *vp;
|
|
void *base;
|
|
size_t len;
|
|
off_t offset;
|
|
enum uio_seg segflg;
|
|
int ioflg;
|
|
struct ucred *active_cred;
|
|
struct ucred *file_cred;
|
|
size_t *aresid;
|
|
struct thread *td;
|
|
{
|
|
int error = 0;
|
|
ssize_t iaresid;
|
|
|
|
do {
|
|
int chunk;
|
|
|
|
/*
|
|
* Force `offset' to a multiple of MAXBSIZE except possibly
|
|
* for the first chunk, so that filesystems only need to
|
|
* write full blocks except possibly for the first and last
|
|
* chunks.
|
|
*/
|
|
chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE;
|
|
|
|
if (chunk > len)
|
|
chunk = len;
|
|
if (rw != UIO_READ && vp->v_type == VREG)
|
|
bwillwrite();
|
|
iaresid = 0;
|
|
error = vn_rdwr(rw, vp, base, chunk, offset, segflg,
|
|
ioflg, active_cred, file_cred, &iaresid, td);
|
|
len -= chunk; /* aresid calc already includes length */
|
|
if (error)
|
|
break;
|
|
offset += chunk;
|
|
base = (char *)base + chunk;
|
|
kern_yield(PRI_USER);
|
|
} while (len);
|
|
if (aresid)
|
|
*aresid = len + iaresid;
|
|
return (error);
|
|
}
|
|
|
|
off_t
|
|
foffset_lock(struct file *fp, int flags)
|
|
{
|
|
struct mtx *mtxp;
|
|
off_t res;
|
|
|
|
KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
|
|
|
|
#if OFF_MAX <= LONG_MAX
|
|
/*
|
|
* Caller only wants the current f_offset value. Assume that
|
|
* the long and shorter integer types reads are atomic.
|
|
*/
|
|
if ((flags & FOF_NOLOCK) != 0)
|
|
return (fp->f_offset);
|
|
#endif
|
|
|
|
/*
|
|
* According to McKusick the vn lock was protecting f_offset here.
|
|
* It is now protected by the FOFFSET_LOCKED flag.
|
|
*/
|
|
mtxp = mtx_pool_find(mtxpool_sleep, fp);
|
|
mtx_lock(mtxp);
|
|
if ((flags & FOF_NOLOCK) == 0) {
|
|
while (fp->f_vnread_flags & FOFFSET_LOCKED) {
|
|
fp->f_vnread_flags |= FOFFSET_LOCK_WAITING;
|
|
msleep(&fp->f_vnread_flags, mtxp, PUSER -1,
|
|
"vofflock", 0);
|
|
}
|
|
fp->f_vnread_flags |= FOFFSET_LOCKED;
|
|
}
|
|
res = fp->f_offset;
|
|
mtx_unlock(mtxp);
|
|
return (res);
|
|
}
|
|
|
|
void
|
|
foffset_unlock(struct file *fp, off_t val, int flags)
|
|
{
|
|
struct mtx *mtxp;
|
|
|
|
KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
|
|
|
|
#if OFF_MAX <= LONG_MAX
|
|
if ((flags & FOF_NOLOCK) != 0) {
|
|
if ((flags & FOF_NOUPDATE) == 0)
|
|
fp->f_offset = val;
|
|
if ((flags & FOF_NEXTOFF) != 0)
|
|
fp->f_nextoff = val;
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
mtxp = mtx_pool_find(mtxpool_sleep, fp);
|
|
mtx_lock(mtxp);
|
|
if ((flags & FOF_NOUPDATE) == 0)
|
|
fp->f_offset = val;
|
|
if ((flags & FOF_NEXTOFF) != 0)
|
|
fp->f_nextoff = val;
|
|
if ((flags & FOF_NOLOCK) == 0) {
|
|
KASSERT((fp->f_vnread_flags & FOFFSET_LOCKED) != 0,
|
|
("Lost FOFFSET_LOCKED"));
|
|
if (fp->f_vnread_flags & FOFFSET_LOCK_WAITING)
|
|
wakeup(&fp->f_vnread_flags);
|
|
fp->f_vnread_flags = 0;
|
|
}
|
|
mtx_unlock(mtxp);
|
|
}
|
|
|
|
void
|
|
foffset_lock_uio(struct file *fp, struct uio *uio, int flags)
|
|
{
|
|
|
|
if ((flags & FOF_OFFSET) == 0)
|
|
uio->uio_offset = foffset_lock(fp, flags);
|
|
}
|
|
|
|
void
|
|
foffset_unlock_uio(struct file *fp, struct uio *uio, int flags)
|
|
{
|
|
|
|
if ((flags & FOF_OFFSET) == 0)
|
|
foffset_unlock(fp, uio->uio_offset, flags);
|
|
}
|
|
|
|
static int
|
|
get_advice(struct file *fp, struct uio *uio)
|
|
{
|
|
struct mtx *mtxp;
|
|
int ret;
|
|
|
|
ret = POSIX_FADV_NORMAL;
|
|
if (fp->f_advice == NULL)
|
|
return (ret);
|
|
|
|
mtxp = mtx_pool_find(mtxpool_sleep, fp);
|
|
mtx_lock(mtxp);
|
|
if (uio->uio_offset >= fp->f_advice->fa_start &&
|
|
uio->uio_offset + uio->uio_resid <= fp->f_advice->fa_end)
|
|
ret = fp->f_advice->fa_advice;
|
|
mtx_unlock(mtxp);
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* File table vnode read routine.
|
|
*/
|
|
static int
|
|
vn_read(fp, uio, active_cred, flags, td)
|
|
struct file *fp;
|
|
struct uio *uio;
|
|
struct ucred *active_cred;
|
|
int flags;
|
|
struct thread *td;
|
|
{
|
|
struct vnode *vp;
|
|
struct mtx *mtxp;
|
|
int error, ioflag;
|
|
int advice;
|
|
off_t offset, start, end;
|
|
|
|
KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
|
|
uio->uio_td, td));
|
|
KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
|
|
vp = fp->f_vnode;
|
|
ioflag = 0;
|
|
if (fp->f_flag & FNONBLOCK)
|
|
ioflag |= IO_NDELAY;
|
|
if (fp->f_flag & O_DIRECT)
|
|
ioflag |= IO_DIRECT;
|
|
advice = get_advice(fp, uio);
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
|
|
switch (advice) {
|
|
case POSIX_FADV_NORMAL:
|
|
case POSIX_FADV_SEQUENTIAL:
|
|
case POSIX_FADV_NOREUSE:
|
|
ioflag |= sequential_heuristic(uio, fp);
|
|
break;
|
|
case POSIX_FADV_RANDOM:
|
|
/* Disable read-ahead for random I/O. */
|
|
break;
|
|
}
|
|
offset = uio->uio_offset;
|
|
|
|
#ifdef MAC
|
|
error = mac_vnode_check_read(active_cred, fp->f_cred, vp);
|
|
if (error == 0)
|
|
#endif
|
|
error = VOP_READ(vp, uio, ioflag, fp->f_cred);
|
|
fp->f_nextoff = uio->uio_offset;
|
|
VOP_UNLOCK(vp, 0);
|
|
if (error == 0 && advice == POSIX_FADV_NOREUSE &&
|
|
offset != uio->uio_offset) {
|
|
/*
|
|
* Use POSIX_FADV_DONTNEED to flush clean pages and
|
|
* buffers for the backing file after a
|
|
* POSIX_FADV_NOREUSE read(2). To optimize the common
|
|
* case of using POSIX_FADV_NOREUSE with sequential
|
|
* access, track the previous implicit DONTNEED
|
|
* request and grow this request to include the
|
|
* current read(2) in addition to the previous
|
|
* DONTNEED. With purely sequential access this will
|
|
* cause the DONTNEED requests to continously grow to
|
|
* cover all of the previously read regions of the
|
|
* file. This allows filesystem blocks that are
|
|
* accessed by multiple calls to read(2) to be flushed
|
|
* once the last read(2) finishes.
|
|
*/
|
|
start = offset;
|
|
end = uio->uio_offset - 1;
|
|
mtxp = mtx_pool_find(mtxpool_sleep, fp);
|
|
mtx_lock(mtxp);
|
|
if (fp->f_advice != NULL &&
|
|
fp->f_advice->fa_advice == POSIX_FADV_NOREUSE) {
|
|
if (start != 0 && fp->f_advice->fa_prevend + 1 == start)
|
|
start = fp->f_advice->fa_prevstart;
|
|
else if (fp->f_advice->fa_prevstart != 0 &&
|
|
fp->f_advice->fa_prevstart == end + 1)
|
|
end = fp->f_advice->fa_prevend;
|
|
fp->f_advice->fa_prevstart = start;
|
|
fp->f_advice->fa_prevend = end;
|
|
}
|
|
mtx_unlock(mtxp);
|
|
error = VOP_ADVISE(vp, start, end, POSIX_FADV_DONTNEED);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode write routine.
|
|
*/
|
|
static int
|
|
vn_write(fp, uio, active_cred, flags, td)
|
|
struct file *fp;
|
|
struct uio *uio;
|
|
struct ucred *active_cred;
|
|
int flags;
|
|
struct thread *td;
|
|
{
|
|
struct vnode *vp;
|
|
struct mount *mp;
|
|
struct mtx *mtxp;
|
|
int error, ioflag, lock_flags;
|
|
int advice;
|
|
off_t offset, start, end;
|
|
|
|
KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
|
|
uio->uio_td, td));
|
|
KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
|
|
vp = fp->f_vnode;
|
|
if (vp->v_type == VREG)
|
|
bwillwrite();
|
|
ioflag = IO_UNIT;
|
|
if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
|
|
ioflag |= IO_APPEND;
|
|
if (fp->f_flag & FNONBLOCK)
|
|
ioflag |= IO_NDELAY;
|
|
if (fp->f_flag & O_DIRECT)
|
|
ioflag |= IO_DIRECT;
|
|
if ((fp->f_flag & O_FSYNC) ||
|
|
(vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
|
|
ioflag |= IO_SYNC;
|
|
mp = NULL;
|
|
if (vp->v_type != VCHR &&
|
|
(error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
|
|
goto unlock;
|
|
|
|
advice = get_advice(fp, uio);
|
|
|
|
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);
|
|
switch (advice) {
|
|
case POSIX_FADV_NORMAL:
|
|
case POSIX_FADV_SEQUENTIAL:
|
|
case POSIX_FADV_NOREUSE:
|
|
ioflag |= sequential_heuristic(uio, fp);
|
|
break;
|
|
case POSIX_FADV_RANDOM:
|
|
/* XXX: Is this correct? */
|
|
break;
|
|
}
|
|
offset = uio->uio_offset;
|
|
|
|
#ifdef MAC
|
|
error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
|
|
if (error == 0)
|
|
#endif
|
|
error = VOP_WRITE(vp, uio, ioflag, fp->f_cred);
|
|
fp->f_nextoff = uio->uio_offset;
|
|
VOP_UNLOCK(vp, 0);
|
|
if (vp->v_type != VCHR)
|
|
vn_finished_write(mp);
|
|
if (error == 0 && advice == POSIX_FADV_NOREUSE &&
|
|
offset != uio->uio_offset) {
|
|
/*
|
|
* Use POSIX_FADV_DONTNEED to flush clean pages and
|
|
* buffers for the backing file after a
|
|
* POSIX_FADV_NOREUSE write(2). To optimize the
|
|
* common case of using POSIX_FADV_NOREUSE with
|
|
* sequential access, track the previous implicit
|
|
* DONTNEED request and grow this request to include
|
|
* the current write(2) in addition to the previous
|
|
* DONTNEED. With purely sequential access this will
|
|
* cause the DONTNEED requests to continously grow to
|
|
* cover all of the previously written regions of the
|
|
* file.
|
|
*
|
|
* Note that the blocks just written are almost
|
|
* certainly still dirty, so this only works when
|
|
* VOP_ADVISE() calls from subsequent writes push out
|
|
* the data written by this write(2) once the backing
|
|
* buffers are clean. However, as compared to forcing
|
|
* IO_DIRECT, this gives much saner behavior. Write
|
|
* clustering is still allowed, and clean pages are
|
|
* merely moved to the cache page queue rather than
|
|
* outright thrown away. This means a subsequent
|
|
* read(2) can still avoid hitting the disk if the
|
|
* pages have not been reclaimed.
|
|
*
|
|
* This does make POSIX_FADV_NOREUSE largely useless
|
|
* with non-sequential access. However, sequential
|
|
* access is the more common use case and the flag is
|
|
* merely advisory.
|
|
*/
|
|
start = offset;
|
|
end = uio->uio_offset - 1;
|
|
mtxp = mtx_pool_find(mtxpool_sleep, fp);
|
|
mtx_lock(mtxp);
|
|
if (fp->f_advice != NULL &&
|
|
fp->f_advice->fa_advice == POSIX_FADV_NOREUSE) {
|
|
if (start != 0 && fp->f_advice->fa_prevend + 1 == start)
|
|
start = fp->f_advice->fa_prevstart;
|
|
else if (fp->f_advice->fa_prevstart != 0 &&
|
|
fp->f_advice->fa_prevstart == end + 1)
|
|
end = fp->f_advice->fa_prevend;
|
|
fp->f_advice->fa_prevstart = start;
|
|
fp->f_advice->fa_prevend = end;
|
|
}
|
|
mtx_unlock(mtxp);
|
|
error = VOP_ADVISE(vp, start, end, POSIX_FADV_DONTNEED);
|
|
}
|
|
|
|
unlock:
|
|
return (error);
|
|
}
|
|
|
|
static const int io_hold_cnt = 16;
|
|
static int vn_io_fault_enable = 1;
|
|
SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_enable, CTLFLAG_RW,
|
|
&vn_io_fault_enable, 0, "Enable vn_io_fault lock avoidance");
|
|
static u_long vn_io_faults_cnt;
|
|
SYSCTL_ULONG(_debug, OID_AUTO, vn_io_faults, CTLFLAG_RD,
|
|
&vn_io_faults_cnt, 0, "Count of vn_io_fault lock avoidance triggers");
|
|
|
|
/*
|
|
* The vn_io_fault() is a wrapper around vn_read() and vn_write() to
|
|
* prevent the following deadlock:
|
|
*
|
|
* Assume that the thread A reads from the vnode vp1 into userspace
|
|
* buffer buf1 backed by the pages of vnode vp2. If a page in buf1 is
|
|
* currently not resident, then system ends up with the call chain
|
|
* vn_read() -> VOP_READ(vp1) -> uiomove() -> [Page Fault] ->
|
|
* vm_fault(buf1) -> vnode_pager_getpages(vp2) -> VOP_GETPAGES(vp2)
|
|
* which establishes lock order vp1->vn_lock, then vp2->vn_lock.
|
|
* If, at the same time, thread B reads from vnode vp2 into buffer buf2
|
|
* backed by the pages of vnode vp1, and some page in buf2 is not
|
|
* resident, we get a reversed order vp2->vn_lock, then vp1->vn_lock.
|
|
*
|
|
* To prevent the lock order reversal and deadlock, vn_io_fault() does
|
|
* not allow page faults to happen during VOP_READ() or VOP_WRITE().
|
|
* Instead, it first tries to do the whole range i/o with pagefaults
|
|
* disabled. If all pages in the i/o buffer are resident and mapped,
|
|
* VOP will succeed (ignoring the genuine filesystem errors).
|
|
* Otherwise, we get back EFAULT, and vn_io_fault() falls back to do
|
|
* i/o in chunks, with all pages in the chunk prefaulted and held
|
|
* using vm_fault_quick_hold_pages().
|
|
*
|
|
* Filesystems using this deadlock avoidance scheme should use the
|
|
* array of the held pages from uio, saved in the curthread->td_ma,
|
|
* instead of doing uiomove(). A helper function
|
|
* vn_io_fault_uiomove() converts uiomove request into
|
|
* uiomove_fromphys() over td_ma array.
|
|
*
|
|
* Since vnode locks do not cover the whole i/o anymore, rangelocks
|
|
* make the current i/o request atomic with respect to other i/os and
|
|
* truncations.
|
|
*/
|
|
static int
|
|
vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
|
|
int flags, struct thread *td)
|
|
{
|
|
vm_page_t ma[io_hold_cnt + 2];
|
|
struct uio *uio_clone, short_uio;
|
|
struct iovec short_iovec[1];
|
|
fo_rdwr_t *doio;
|
|
struct vnode *vp;
|
|
void *rl_cookie;
|
|
struct mount *mp;
|
|
vm_page_t *prev_td_ma;
|
|
int error, cnt, save, saveheld, prev_td_ma_cnt;
|
|
vm_offset_t addr, end;
|
|
vm_prot_t prot;
|
|
size_t len, resid;
|
|
ssize_t adv;
|
|
|
|
if (uio->uio_rw == UIO_READ)
|
|
doio = vn_read;
|
|
else
|
|
doio = vn_write;
|
|
vp = fp->f_vnode;
|
|
foffset_lock_uio(fp, uio, flags);
|
|
|
|
if (uio->uio_segflg != UIO_USERSPACE || vp->v_type != VREG ||
|
|
((mp = vp->v_mount) != NULL &&
|
|
(mp->mnt_kern_flag & MNTK_NO_IOPF) == 0) ||
|
|
!vn_io_fault_enable) {
|
|
error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
|
|
goto out_last;
|
|
}
|
|
|
|
/*
|
|
* The UFS follows IO_UNIT directive and replays back both
|
|
* uio_offset and uio_resid if an error is encountered during the
|
|
* operation. But, since the iovec may be already advanced,
|
|
* uio is still in an inconsistent state.
|
|
*
|
|
* Cache a copy of the original uio, which is advanced to the redo
|
|
* point using UIO_NOCOPY below.
|
|
*/
|
|
uio_clone = cloneuio(uio);
|
|
resid = uio->uio_resid;
|
|
|
|
short_uio.uio_segflg = UIO_USERSPACE;
|
|
short_uio.uio_rw = uio->uio_rw;
|
|
short_uio.uio_td = uio->uio_td;
|
|
|
|
if (uio->uio_rw == UIO_READ) {
|
|
prot = VM_PROT_WRITE;
|
|
rl_cookie = vn_rangelock_rlock(vp, uio->uio_offset,
|
|
uio->uio_offset + uio->uio_resid);
|
|
} else {
|
|
prot = VM_PROT_READ;
|
|
if ((fp->f_flag & O_APPEND) != 0 || (flags & FOF_OFFSET) == 0)
|
|
/* For appenders, punt and lock the whole range. */
|
|
rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
|
|
else
|
|
rl_cookie = vn_rangelock_wlock(vp, uio->uio_offset,
|
|
uio->uio_offset + uio->uio_resid);
|
|
}
|
|
|
|
save = vm_fault_disable_pagefaults();
|
|
error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
|
|
if (error != EFAULT)
|
|
goto out;
|
|
|
|
atomic_add_long(&vn_io_faults_cnt, 1);
|
|
uio_clone->uio_segflg = UIO_NOCOPY;
|
|
uiomove(NULL, resid - uio->uio_resid, uio_clone);
|
|
uio_clone->uio_segflg = uio->uio_segflg;
|
|
|
|
saveheld = curthread_pflags_set(TDP_UIOHELD);
|
|
prev_td_ma = td->td_ma;
|
|
prev_td_ma_cnt = td->td_ma_cnt;
|
|
|
|
while (uio_clone->uio_resid != 0) {
|
|
len = uio_clone->uio_iov->iov_len;
|
|
if (len == 0) {
|
|
KASSERT(uio_clone->uio_iovcnt >= 1,
|
|
("iovcnt underflow"));
|
|
uio_clone->uio_iov++;
|
|
uio_clone->uio_iovcnt--;
|
|
continue;
|
|
}
|
|
if (len > io_hold_cnt * PAGE_SIZE)
|
|
len = io_hold_cnt * PAGE_SIZE;
|
|
addr = (uintptr_t)uio_clone->uio_iov->iov_base;
|
|
end = round_page(addr + len);
|
|
if (end < addr) {
|
|
error = EFAULT;
|
|
break;
|
|
}
|
|
cnt = atop(end - trunc_page(addr));
|
|
/*
|
|
* A perfectly misaligned address and length could cause
|
|
* both the start and the end of the chunk to use partial
|
|
* page. +2 accounts for such a situation.
|
|
*/
|
|
cnt = vm_fault_quick_hold_pages(&td->td_proc->p_vmspace->vm_map,
|
|
addr, len, prot, ma, io_hold_cnt + 2);
|
|
if (cnt == -1) {
|
|
error = EFAULT;
|
|
break;
|
|
}
|
|
short_uio.uio_iov = &short_iovec[0];
|
|
short_iovec[0].iov_base = (void *)addr;
|
|
short_uio.uio_iovcnt = 1;
|
|
short_uio.uio_resid = short_iovec[0].iov_len = len;
|
|
short_uio.uio_offset = uio_clone->uio_offset;
|
|
td->td_ma = ma;
|
|
td->td_ma_cnt = cnt;
|
|
|
|
error = doio(fp, &short_uio, active_cred, flags | FOF_OFFSET,
|
|
td);
|
|
vm_page_unhold_pages(ma, cnt);
|
|
adv = len - short_uio.uio_resid;
|
|
|
|
uio_clone->uio_iov->iov_base =
|
|
(char *)uio_clone->uio_iov->iov_base + adv;
|
|
uio_clone->uio_iov->iov_len -= adv;
|
|
uio_clone->uio_resid -= adv;
|
|
uio_clone->uio_offset += adv;
|
|
|
|
uio->uio_resid -= adv;
|
|
uio->uio_offset += adv;
|
|
|
|
if (error != 0 || adv == 0)
|
|
break;
|
|
}
|
|
td->td_ma = prev_td_ma;
|
|
td->td_ma_cnt = prev_td_ma_cnt;
|
|
curthread_pflags_restore(saveheld);
|
|
out:
|
|
vm_fault_enable_pagefaults(save);
|
|
vn_rangelock_unlock(vp, rl_cookie);
|
|
free(uio_clone, M_IOV);
|
|
out_last:
|
|
foffset_unlock_uio(fp, uio, flags);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Helper function to perform the requested uiomove operation using
|
|
* the held pages for io->uio_iov[0].iov_base buffer instead of
|
|
* copyin/copyout. Access to the pages with uiomove_fromphys()
|
|
* instead of iov_base prevents page faults that could occur due to
|
|
* pmap_collect() invalidating the mapping created by
|
|
* vm_fault_quick_hold_pages(), or pageout daemon, page laundry or
|
|
* object cleanup revoking the write access from page mappings.
|
|
*
|
|
* Filesystems specified MNTK_NO_IOPF shall use vn_io_fault_uiomove()
|
|
* instead of plain uiomove().
|
|
*/
|
|
int
|
|
vn_io_fault_uiomove(char *data, int xfersize, struct uio *uio)
|
|
{
|
|
struct uio transp_uio;
|
|
struct iovec transp_iov[1];
|
|
struct thread *td;
|
|
size_t adv;
|
|
int error, pgadv;
|
|
|
|
td = curthread;
|
|
if ((td->td_pflags & TDP_UIOHELD) == 0 ||
|
|
uio->uio_segflg != UIO_USERSPACE)
|
|
return (uiomove(data, xfersize, uio));
|
|
|
|
KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
|
|
transp_iov[0].iov_base = data;
|
|
transp_uio.uio_iov = &transp_iov[0];
|
|
transp_uio.uio_iovcnt = 1;
|
|
if (xfersize > uio->uio_resid)
|
|
xfersize = uio->uio_resid;
|
|
transp_uio.uio_resid = transp_iov[0].iov_len = xfersize;
|
|
transp_uio.uio_offset = 0;
|
|
transp_uio.uio_segflg = UIO_SYSSPACE;
|
|
/*
|
|
* Since transp_iov points to data, and td_ma page array
|
|
* corresponds to original uio->uio_iov, we need to invert the
|
|
* direction of the i/o operation as passed to
|
|
* uiomove_fromphys().
|
|
*/
|
|
switch (uio->uio_rw) {
|
|
case UIO_WRITE:
|
|
transp_uio.uio_rw = UIO_READ;
|
|
break;
|
|
case UIO_READ:
|
|
transp_uio.uio_rw = UIO_WRITE;
|
|
break;
|
|
}
|
|
transp_uio.uio_td = uio->uio_td;
|
|
error = uiomove_fromphys(td->td_ma,
|
|
((vm_offset_t)uio->uio_iov->iov_base) & PAGE_MASK,
|
|
xfersize, &transp_uio);
|
|
adv = xfersize - transp_uio.uio_resid;
|
|
pgadv =
|
|
(((vm_offset_t)uio->uio_iov->iov_base + adv) >> PAGE_SHIFT) -
|
|
(((vm_offset_t)uio->uio_iov->iov_base) >> PAGE_SHIFT);
|
|
td->td_ma += pgadv;
|
|
KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
|
|
pgadv));
|
|
td->td_ma_cnt -= pgadv;
|
|
uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + adv;
|
|
uio->uio_iov->iov_len -= adv;
|
|
uio->uio_resid -= adv;
|
|
uio->uio_offset += adv;
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_io_fault_pgmove(vm_page_t ma[], vm_offset_t offset, int xfersize,
|
|
struct uio *uio)
|
|
{
|
|
struct thread *td;
|
|
vm_offset_t iov_base;
|
|
int cnt, pgadv;
|
|
|
|
td = curthread;
|
|
if ((td->td_pflags & TDP_UIOHELD) == 0 ||
|
|
uio->uio_segflg != UIO_USERSPACE)
|
|
return (uiomove_fromphys(ma, offset, xfersize, uio));
|
|
|
|
KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
|
|
cnt = xfersize > uio->uio_resid ? uio->uio_resid : xfersize;
|
|
iov_base = (vm_offset_t)uio->uio_iov->iov_base;
|
|
switch (uio->uio_rw) {
|
|
case UIO_WRITE:
|
|
pmap_copy_pages(td->td_ma, iov_base & PAGE_MASK, ma,
|
|
offset, cnt);
|
|
break;
|
|
case UIO_READ:
|
|
pmap_copy_pages(ma, offset, td->td_ma, iov_base & PAGE_MASK,
|
|
cnt);
|
|
break;
|
|
}
|
|
pgadv = ((iov_base + cnt) >> PAGE_SHIFT) - (iov_base >> PAGE_SHIFT);
|
|
td->td_ma += pgadv;
|
|
KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
|
|
pgadv));
|
|
td->td_ma_cnt -= pgadv;
|
|
uio->uio_iov->iov_base = (char *)(iov_base + cnt);
|
|
uio->uio_iov->iov_len -= cnt;
|
|
uio->uio_resid -= cnt;
|
|
uio->uio_offset += cnt;
|
|
return (0);
|
|
}
|
|
|
|
|
|
/*
|
|
* File table truncate routine.
|
|
*/
|
|
static int
|
|
vn_truncate(struct file *fp, off_t length, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct vattr vattr;
|
|
struct mount *mp;
|
|
struct vnode *vp;
|
|
void *rl_cookie;
|
|
int error;
|
|
|
|
vp = fp->f_vnode;
|
|
|
|
/*
|
|
* Lock the whole range for truncation. Otherwise split i/o
|
|
* might happen partly before and partly after the truncation.
|
|
*/
|
|
rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
|
|
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
|
|
if (error)
|
|
goto out1;
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
|
if (vp->v_type == VDIR) {
|
|
error = EISDIR;
|
|
goto out;
|
|
}
|
|
#ifdef MAC
|
|
error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
|
|
if (error)
|
|
goto out;
|
|
#endif
|
|
error = vn_writechk(vp);
|
|
if (error == 0) {
|
|
VATTR_NULL(&vattr);
|
|
vattr.va_size = length;
|
|
error = VOP_SETATTR(vp, &vattr, fp->f_cred);
|
|
}
|
|
out:
|
|
VOP_UNLOCK(vp, 0);
|
|
vn_finished_write(mp);
|
|
out1:
|
|
vn_rangelock_unlock(vp, rl_cookie);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode stat routine.
|
|
*/
|
|
static int
|
|
vn_statfile(fp, sb, active_cred, td)
|
|
struct file *fp;
|
|
struct stat *sb;
|
|
struct ucred *active_cred;
|
|
struct thread *td;
|
|
{
|
|
struct vnode *vp = fp->f_vnode;
|
|
int error;
|
|
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
error = vn_stat(vp, sb, active_cred, fp->f_cred, td);
|
|
VOP_UNLOCK(vp, 0);
|
|
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Stat a vnode; implementation for the stat syscall
|
|
*/
|
|
int
|
|
vn_stat(vp, sb, active_cred, file_cred, td)
|
|
struct vnode *vp;
|
|
register struct stat *sb;
|
|
struct ucred *active_cred;
|
|
struct ucred *file_cred;
|
|
struct thread *td;
|
|
{
|
|
struct vattr vattr;
|
|
register struct vattr *vap;
|
|
int error;
|
|
u_short mode;
|
|
|
|
#ifdef MAC
|
|
error = mac_vnode_check_stat(active_cred, file_cred, vp);
|
|
if (error)
|
|
return (error);
|
|
#endif
|
|
|
|
vap = &vattr;
|
|
|
|
/*
|
|
* Initialize defaults for new and unusual fields, so that file
|
|
* systems which don't support these fields don't need to know
|
|
* about them.
|
|
*/
|
|
vap->va_birthtime.tv_sec = -1;
|
|
vap->va_birthtime.tv_nsec = 0;
|
|
vap->va_fsid = VNOVAL;
|
|
vap->va_rdev = NODEV;
|
|
|
|
error = VOP_GETATTR(vp, vap, active_cred);
|
|
if (error)
|
|
return (error);
|
|
|
|
/*
|
|
* Zero the spare stat fields
|
|
*/
|
|
bzero(sb, sizeof *sb);
|
|
|
|
/*
|
|
* Copy from vattr table
|
|
*/
|
|
if (vap->va_fsid != VNOVAL)
|
|
sb->st_dev = vap->va_fsid;
|
|
else
|
|
sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0];
|
|
sb->st_ino = vap->va_fileid;
|
|
mode = vap->va_mode;
|
|
switch (vap->va_type) {
|
|
case VREG:
|
|
mode |= S_IFREG;
|
|
break;
|
|
case VDIR:
|
|
mode |= S_IFDIR;
|
|
break;
|
|
case VBLK:
|
|
mode |= S_IFBLK;
|
|
break;
|
|
case VCHR:
|
|
mode |= S_IFCHR;
|
|
break;
|
|
case VLNK:
|
|
mode |= S_IFLNK;
|
|
break;
|
|
case VSOCK:
|
|
mode |= S_IFSOCK;
|
|
break;
|
|
case VFIFO:
|
|
mode |= S_IFIFO;
|
|
break;
|
|
default:
|
|
return (EBADF);
|
|
};
|
|
sb->st_mode = mode;
|
|
sb->st_nlink = vap->va_nlink;
|
|
sb->st_uid = vap->va_uid;
|
|
sb->st_gid = vap->va_gid;
|
|
sb->st_rdev = vap->va_rdev;
|
|
if (vap->va_size > OFF_MAX)
|
|
return (EOVERFLOW);
|
|
sb->st_size = vap->va_size;
|
|
sb->st_atim = vap->va_atime;
|
|
sb->st_mtim = vap->va_mtime;
|
|
sb->st_ctim = vap->va_ctime;
|
|
sb->st_birthtim = vap->va_birthtime;
|
|
|
|
/*
|
|
* According to www.opengroup.org, the meaning of st_blksize is
|
|
* "a filesystem-specific preferred I/O block size for this
|
|
* object. In some filesystem types, this may vary from file
|
|
* to file"
|
|
* Use miminum/default of PAGE_SIZE (e.g. for VCHR).
|
|
*/
|
|
|
|
sb->st_blksize = max(PAGE_SIZE, vap->va_blocksize);
|
|
|
|
sb->st_flags = vap->va_flags;
|
|
if (priv_check(td, PRIV_VFS_GENERATION))
|
|
sb->st_gen = 0;
|
|
else
|
|
sb->st_gen = vap->va_gen;
|
|
|
|
sb->st_blocks = vap->va_bytes / S_BLKSIZE;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* File table vnode ioctl routine.
|
|
*/
|
|
static int
|
|
vn_ioctl(fp, com, data, active_cred, td)
|
|
struct file *fp;
|
|
u_long com;
|
|
void *data;
|
|
struct ucred *active_cred;
|
|
struct thread *td;
|
|
{
|
|
struct vattr vattr;
|
|
struct vnode *vp;
|
|
int error;
|
|
|
|
vp = fp->f_vnode;
|
|
switch (vp->v_type) {
|
|
case VDIR:
|
|
case VREG:
|
|
switch (com) {
|
|
case FIONREAD:
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
error = VOP_GETATTR(vp, &vattr, active_cred);
|
|
VOP_UNLOCK(vp, 0);
|
|
if (error == 0)
|
|
*(int *)data = vattr.va_size - fp->f_offset;
|
|
return (error);
|
|
case FIONBIO:
|
|
case FIOASYNC:
|
|
return (0);
|
|
default:
|
|
return (VOP_IOCTL(vp, com, data, fp->f_flag,
|
|
active_cred, td));
|
|
}
|
|
default:
|
|
return (ENOTTY);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* File table vnode poll routine.
|
|
*/
|
|
static int
|
|
vn_poll(fp, events, active_cred, td)
|
|
struct file *fp;
|
|
int events;
|
|
struct ucred *active_cred;
|
|
struct thread *td;
|
|
{
|
|
struct vnode *vp;
|
|
int error;
|
|
|
|
vp = fp->f_vnode;
|
|
#ifdef MAC
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
|
error = mac_vnode_check_poll(active_cred, fp->f_cred, vp);
|
|
VOP_UNLOCK(vp, 0);
|
|
if (!error)
|
|
#endif
|
|
|
|
error = VOP_POLL(vp, events, fp->f_cred, td);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Acquire the requested lock and then check for validity. LK_RETRY
|
|
* permits vn_lock to return doomed vnodes.
|
|
*/
|
|
int
|
|
_vn_lock(struct vnode *vp, int flags, char *file, int line)
|
|
{
|
|
int error;
|
|
|
|
VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
|
|
("vn_lock called with no locktype."));
|
|
do {
|
|
#ifdef DEBUG_VFS_LOCKS
|
|
KASSERT(vp->v_holdcnt != 0,
|
|
("vn_lock %p: zero hold count", vp));
|
|
#endif
|
|
error = VOP_LOCK1(vp, flags, file, line);
|
|
flags &= ~LK_INTERLOCK; /* Interlock is always dropped. */
|
|
KASSERT((flags & LK_RETRY) == 0 || error == 0,
|
|
("LK_RETRY set with incompatible flags (0x%x) or an error occured (%d)",
|
|
flags, error));
|
|
/*
|
|
* Callers specify LK_RETRY if they wish to get dead vnodes.
|
|
* If RETRY is not set, we return ENOENT instead.
|
|
*/
|
|
if (error == 0 && vp->v_iflag & VI_DOOMED &&
|
|
(flags & LK_RETRY) == 0) {
|
|
VOP_UNLOCK(vp, 0);
|
|
error = ENOENT;
|
|
break;
|
|
}
|
|
} while (flags & LK_RETRY && error != 0);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode close routine.
|
|
*/
|
|
static int
|
|
vn_closefile(fp, td)
|
|
struct file *fp;
|
|
struct thread *td;
|
|
{
|
|
struct vnode *vp;
|
|
struct flock lf;
|
|
int error;
|
|
|
|
vp = fp->f_vnode;
|
|
fp->f_ops = &badfileops;
|
|
|
|
if (fp->f_type == DTYPE_VNODE && fp->f_flag & FHASLOCK)
|
|
vref(vp);
|
|
|
|
error = vn_close(vp, fp->f_flag, fp->f_cred, td);
|
|
|
|
if (fp->f_type == DTYPE_VNODE && fp->f_flag & FHASLOCK) {
|
|
lf.l_whence = SEEK_SET;
|
|
lf.l_start = 0;
|
|
lf.l_len = 0;
|
|
lf.l_type = F_UNLCK;
|
|
(void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
|
|
vrele(vp);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Preparing to start a filesystem write operation. If the operation is
|
|
* permitted, then we bump the count of operations in progress and
|
|
* proceed. If a suspend request is in progress, we wait until the
|
|
* suspension is over, and then proceed.
|
|
*/
|
|
static int
|
|
vn_start_write_locked(struct mount *mp, int flags)
|
|
{
|
|
int error;
|
|
|
|
mtx_assert(MNT_MTX(mp), MA_OWNED);
|
|
error = 0;
|
|
|
|
/*
|
|
* Check on status of suspension.
|
|
*/
|
|
if ((curthread->td_pflags & TDP_IGNSUSP) == 0 ||
|
|
mp->mnt_susp_owner != curthread) {
|
|
while ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
|
|
if (flags & V_NOWAIT) {
|
|
error = EWOULDBLOCK;
|
|
goto unlock;
|
|
}
|
|
error = msleep(&mp->mnt_flag, MNT_MTX(mp),
|
|
(PUSER - 1) | (flags & PCATCH), "suspfs", 0);
|
|
if (error)
|
|
goto unlock;
|
|
}
|
|
}
|
|
if (flags & V_XSLEEP)
|
|
goto unlock;
|
|
mp->mnt_writeopcount++;
|
|
unlock:
|
|
if (error != 0 || (flags & V_XSLEEP) != 0)
|
|
MNT_REL(mp);
|
|
MNT_IUNLOCK(mp);
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_start_write(vp, mpp, flags)
|
|
struct vnode *vp;
|
|
struct mount **mpp;
|
|
int flags;
|
|
{
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
error = 0;
|
|
/*
|
|
* If a vnode is provided, get and return the mount point that
|
|
* to which it will write.
|
|
*/
|
|
if (vp != NULL) {
|
|
if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
|
|
*mpp = NULL;
|
|
if (error != EOPNOTSUPP)
|
|
return (error);
|
|
return (0);
|
|
}
|
|
}
|
|
if ((mp = *mpp) == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* VOP_GETWRITEMOUNT() returns with the mp refcount held through
|
|
* a vfs_ref().
|
|
* As long as a vnode is not provided we need to acquire a
|
|
* refcount for the provided mountpoint too, in order to
|
|
* emulate a vfs_ref().
|
|
*/
|
|
MNT_ILOCK(mp);
|
|
if (vp == NULL)
|
|
MNT_REF(mp);
|
|
|
|
return (vn_start_write_locked(mp, flags));
|
|
}
|
|
|
|
/*
|
|
* Secondary suspension. Used by operations such as vop_inactive
|
|
* routines that are needed by the higher level functions. These
|
|
* are allowed to proceed until all the higher level functions have
|
|
* completed (indicated by mnt_writeopcount dropping to zero). At that
|
|
* time, these operations are halted until the suspension is over.
|
|
*/
|
|
int
|
|
vn_start_secondary_write(vp, mpp, flags)
|
|
struct vnode *vp;
|
|
struct mount **mpp;
|
|
int flags;
|
|
{
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
retry:
|
|
if (vp != NULL) {
|
|
if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
|
|
*mpp = NULL;
|
|
if (error != EOPNOTSUPP)
|
|
return (error);
|
|
return (0);
|
|
}
|
|
}
|
|
/*
|
|
* If we are not suspended or have not yet reached suspended
|
|
* mode, then let the operation proceed.
|
|
*/
|
|
if ((mp = *mpp) == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* VOP_GETWRITEMOUNT() returns with the mp refcount held through
|
|
* a vfs_ref().
|
|
* As long as a vnode is not provided we need to acquire a
|
|
* refcount for the provided mountpoint too, in order to
|
|
* emulate a vfs_ref().
|
|
*/
|
|
MNT_ILOCK(mp);
|
|
if (vp == NULL)
|
|
MNT_REF(mp);
|
|
if ((mp->mnt_kern_flag & (MNTK_SUSPENDED | MNTK_SUSPEND2)) == 0) {
|
|
mp->mnt_secondary_writes++;
|
|
mp->mnt_secondary_accwrites++;
|
|
MNT_IUNLOCK(mp);
|
|
return (0);
|
|
}
|
|
if (flags & V_NOWAIT) {
|
|
MNT_REL(mp);
|
|
MNT_IUNLOCK(mp);
|
|
return (EWOULDBLOCK);
|
|
}
|
|
/*
|
|
* Wait for the suspension to finish.
|
|
*/
|
|
error = msleep(&mp->mnt_flag, MNT_MTX(mp),
|
|
(PUSER - 1) | (flags & PCATCH) | PDROP, "suspfs", 0);
|
|
vfs_rel(mp);
|
|
if (error == 0)
|
|
goto retry;
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Filesystem write operation has completed. If we are suspending and this
|
|
* operation is the last one, notify the suspender that the suspension is
|
|
* now in effect.
|
|
*/
|
|
void
|
|
vn_finished_write(mp)
|
|
struct mount *mp;
|
|
{
|
|
if (mp == NULL)
|
|
return;
|
|
MNT_ILOCK(mp);
|
|
MNT_REL(mp);
|
|
mp->mnt_writeopcount--;
|
|
if (mp->mnt_writeopcount < 0)
|
|
panic("vn_finished_write: neg cnt");
|
|
if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
|
|
mp->mnt_writeopcount <= 0)
|
|
wakeup(&mp->mnt_writeopcount);
|
|
MNT_IUNLOCK(mp);
|
|
}
|
|
|
|
|
|
/*
|
|
* Filesystem secondary write operation has completed. If we are
|
|
* suspending and this operation is the last one, notify the suspender
|
|
* that the suspension is now in effect.
|
|
*/
|
|
void
|
|
vn_finished_secondary_write(mp)
|
|
struct mount *mp;
|
|
{
|
|
if (mp == NULL)
|
|
return;
|
|
MNT_ILOCK(mp);
|
|
MNT_REL(mp);
|
|
mp->mnt_secondary_writes--;
|
|
if (mp->mnt_secondary_writes < 0)
|
|
panic("vn_finished_secondary_write: neg cnt");
|
|
if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
|
|
mp->mnt_secondary_writes <= 0)
|
|
wakeup(&mp->mnt_secondary_writes);
|
|
MNT_IUNLOCK(mp);
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
* Request a filesystem to suspend write operations.
|
|
*/
|
|
int
|
|
vfs_write_suspend(struct mount *mp, int flags)
|
|
{
|
|
int error;
|
|
|
|
MNT_ILOCK(mp);
|
|
if (mp->mnt_susp_owner == curthread) {
|
|
MNT_IUNLOCK(mp);
|
|
return (EALREADY);
|
|
}
|
|
while (mp->mnt_kern_flag & MNTK_SUSPEND)
|
|
msleep(&mp->mnt_flag, MNT_MTX(mp), PUSER - 1, "wsuspfs", 0);
|
|
|
|
/*
|
|
* Unmount holds a write reference on the mount point. If we
|
|
* own busy reference and drain for writers, we deadlock with
|
|
* the reference draining in the unmount path. Callers of
|
|
* vfs_write_suspend() must specify VS_SKIP_UNMOUNT if
|
|
* vfs_busy() reference is owned and caller is not in the
|
|
* unmount context.
|
|
*/
|
|
if ((flags & VS_SKIP_UNMOUNT) != 0 &&
|
|
(mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) {
|
|
MNT_IUNLOCK(mp);
|
|
return (EBUSY);
|
|
}
|
|
|
|
mp->mnt_kern_flag |= MNTK_SUSPEND;
|
|
mp->mnt_susp_owner = curthread;
|
|
if (mp->mnt_writeopcount > 0)
|
|
(void) msleep(&mp->mnt_writeopcount,
|
|
MNT_MTX(mp), (PUSER - 1)|PDROP, "suspwt", 0);
|
|
else
|
|
MNT_IUNLOCK(mp);
|
|
if ((error = VFS_SYNC(mp, MNT_SUSPEND)) != 0)
|
|
vfs_write_resume(mp, 0);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Request a filesystem to resume write operations.
|
|
*/
|
|
void
|
|
vfs_write_resume(struct mount *mp, int flags)
|
|
{
|
|
|
|
MNT_ILOCK(mp);
|
|
if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
|
|
KASSERT(mp->mnt_susp_owner == curthread, ("mnt_susp_owner"));
|
|
mp->mnt_kern_flag &= ~(MNTK_SUSPEND | MNTK_SUSPEND2 |
|
|
MNTK_SUSPENDED);
|
|
mp->mnt_susp_owner = NULL;
|
|
wakeup(&mp->mnt_writeopcount);
|
|
wakeup(&mp->mnt_flag);
|
|
curthread->td_pflags &= ~TDP_IGNSUSP;
|
|
if ((flags & VR_START_WRITE) != 0) {
|
|
MNT_REF(mp);
|
|
mp->mnt_writeopcount++;
|
|
}
|
|
MNT_IUNLOCK(mp);
|
|
if ((flags & VR_NO_SUSPCLR) == 0)
|
|
VFS_SUSP_CLEAN(mp);
|
|
} else if ((flags & VR_START_WRITE) != 0) {
|
|
MNT_REF(mp);
|
|
vn_start_write_locked(mp, 0);
|
|
} else {
|
|
MNT_IUNLOCK(mp);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Implement kqueues for files by translating it to vnode operation.
|
|
*/
|
|
static int
|
|
vn_kqfilter(struct file *fp, struct knote *kn)
|
|
{
|
|
|
|
return (VOP_KQFILTER(fp->f_vnode, kn));
|
|
}
|
|
|
|
/*
|
|
* Simplified in-kernel wrapper calls for extended attribute access.
|
|
* Both calls pass in a NULL credential, authorizing as "kernel" access.
|
|
* Set IO_NODELOCKED in ioflg if the vnode is already locked.
|
|
*/
|
|
int
|
|
vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
|
|
const char *attrname, int *buflen, char *buf, struct thread *td)
|
|
{
|
|
struct uio auio;
|
|
struct iovec iov;
|
|
int error;
|
|
|
|
iov.iov_len = *buflen;
|
|
iov.iov_base = buf;
|
|
|
|
auio.uio_iov = &iov;
|
|
auio.uio_iovcnt = 1;
|
|
auio.uio_rw = UIO_READ;
|
|
auio.uio_segflg = UIO_SYSSPACE;
|
|
auio.uio_td = td;
|
|
auio.uio_offset = 0;
|
|
auio.uio_resid = *buflen;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0)
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
|
|
ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
|
|
|
|
/* authorize attribute retrieval as kernel */
|
|
error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL,
|
|
td);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0)
|
|
VOP_UNLOCK(vp, 0);
|
|
|
|
if (error == 0) {
|
|
*buflen = *buflen - auio.uio_resid;
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* XXX failure mode if partially written?
|
|
*/
|
|
int
|
|
vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
|
|
const char *attrname, int buflen, char *buf, struct thread *td)
|
|
{
|
|
struct uio auio;
|
|
struct iovec iov;
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
iov.iov_len = buflen;
|
|
iov.iov_base = buf;
|
|
|
|
auio.uio_iov = &iov;
|
|
auio.uio_iovcnt = 1;
|
|
auio.uio_rw = UIO_WRITE;
|
|
auio.uio_segflg = UIO_SYSSPACE;
|
|
auio.uio_td = td;
|
|
auio.uio_offset = 0;
|
|
auio.uio_resid = buflen;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
|
|
return (error);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
|
}
|
|
|
|
ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
|
|
|
|
/* authorize attribute setting as kernel */
|
|
error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, td);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
vn_finished_write(mp);
|
|
VOP_UNLOCK(vp, 0);
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
|
|
const char *attrname, struct thread *td)
|
|
{
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
|
|
return (error);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
|
}
|
|
|
|
ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
|
|
|
|
/* authorize attribute removal as kernel */
|
|
error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, td);
|
|
if (error == EOPNOTSUPP)
|
|
error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
|
|
NULL, td);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
vn_finished_write(mp);
|
|
VOP_UNLOCK(vp, 0);
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_vget_ino(struct vnode *vp, ino_t ino, int lkflags, struct vnode **rvp)
|
|
{
|
|
struct mount *mp;
|
|
int ltype, error;
|
|
|
|
mp = vp->v_mount;
|
|
ltype = VOP_ISLOCKED(vp);
|
|
KASSERT(ltype == LK_EXCLUSIVE || ltype == LK_SHARED,
|
|
("vn_vget_ino: vp not locked"));
|
|
error = vfs_busy(mp, MBF_NOWAIT);
|
|
if (error != 0) {
|
|
vfs_ref(mp);
|
|
VOP_UNLOCK(vp, 0);
|
|
error = vfs_busy(mp, 0);
|
|
vn_lock(vp, ltype | LK_RETRY);
|
|
vfs_rel(mp);
|
|
if (error != 0)
|
|
return (ENOENT);
|
|
if (vp->v_iflag & VI_DOOMED) {
|
|
vfs_unbusy(mp);
|
|
return (ENOENT);
|
|
}
|
|
}
|
|
VOP_UNLOCK(vp, 0);
|
|
error = VFS_VGET(mp, ino, lkflags, rvp);
|
|
vfs_unbusy(mp);
|
|
vn_lock(vp, ltype | LK_RETRY);
|
|
if (vp->v_iflag & VI_DOOMED) {
|
|
if (error == 0)
|
|
vput(*rvp);
|
|
error = ENOENT;
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_rlimit_fsize(const struct vnode *vp, const struct uio *uio,
|
|
const struct thread *td)
|
|
{
|
|
|
|
if (vp->v_type != VREG || td == NULL)
|
|
return (0);
|
|
PROC_LOCK(td->td_proc);
|
|
if ((uoff_t)uio->uio_offset + uio->uio_resid >
|
|
lim_cur(td->td_proc, RLIMIT_FSIZE)) {
|
|
kern_psignal(td->td_proc, SIGXFSZ);
|
|
PROC_UNLOCK(td->td_proc);
|
|
return (EFBIG);
|
|
}
|
|
PROC_UNLOCK(td->td_proc);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
vn_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct vnode *vp;
|
|
|
|
vp = fp->f_vnode;
|
|
#ifdef AUDIT
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
AUDIT_ARG_VNODE1(vp);
|
|
VOP_UNLOCK(vp, 0);
|
|
#endif
|
|
return (setfmode(td, active_cred, vp, mode));
|
|
}
|
|
|
|
int
|
|
vn_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
|
|
struct thread *td)
|
|
{
|
|
struct vnode *vp;
|
|
|
|
vp = fp->f_vnode;
|
|
#ifdef AUDIT
|
|
vn_lock(vp, LK_SHARED | LK_RETRY);
|
|
AUDIT_ARG_VNODE1(vp);
|
|
VOP_UNLOCK(vp, 0);
|
|
#endif
|
|
return (setfown(td, active_cred, vp, uid, gid));
|
|
}
|
|
|
|
void
|
|
vn_pages_remove(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
|
|
{
|
|
vm_object_t object;
|
|
|
|
if ((object = vp->v_object) == NULL)
|
|
return;
|
|
VM_OBJECT_WLOCK(object);
|
|
vm_object_page_remove(object, start, end, 0);
|
|
VM_OBJECT_WUNLOCK(object);
|
|
}
|
|
|
|
int
|
|
vn_bmap_seekhole(struct vnode *vp, u_long cmd, off_t *off, struct ucred *cred)
|
|
{
|
|
struct vattr va;
|
|
daddr_t bn, bnp;
|
|
uint64_t bsize;
|
|
off_t noff;
|
|
int error;
|
|
|
|
KASSERT(cmd == FIOSEEKHOLE || cmd == FIOSEEKDATA,
|
|
("Wrong command %lu", cmd));
|
|
|
|
if (vn_lock(vp, LK_SHARED) != 0)
|
|
return (EBADF);
|
|
if (vp->v_type != VREG) {
|
|
error = ENOTTY;
|
|
goto unlock;
|
|
}
|
|
error = VOP_GETATTR(vp, &va, cred);
|
|
if (error != 0)
|
|
goto unlock;
|
|
noff = *off;
|
|
if (noff >= va.va_size) {
|
|
error = ENXIO;
|
|
goto unlock;
|
|
}
|
|
bsize = vp->v_mount->mnt_stat.f_iosize;
|
|
for (bn = noff / bsize; noff < va.va_size; bn++, noff += bsize) {
|
|
error = VOP_BMAP(vp, bn, NULL, &bnp, NULL, NULL);
|
|
if (error == EOPNOTSUPP) {
|
|
error = ENOTTY;
|
|
goto unlock;
|
|
}
|
|
if ((bnp == -1 && cmd == FIOSEEKHOLE) ||
|
|
(bnp != -1 && cmd == FIOSEEKDATA)) {
|
|
noff = bn * bsize;
|
|
if (noff < *off)
|
|
noff = *off;
|
|
goto unlock;
|
|
}
|
|
}
|
|
if (noff > va.va_size)
|
|
noff = va.va_size;
|
|
/* noff == va.va_size. There is an implicit hole at the end of file. */
|
|
if (cmd == FIOSEEKDATA)
|
|
error = ENXIO;
|
|
unlock:
|
|
VOP_UNLOCK(vp, 0);
|
|
if (error == 0)
|
|
*off = noff;
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_seek(struct file *fp, off_t offset, int whence, struct thread *td)
|
|
{
|
|
struct ucred *cred;
|
|
struct vnode *vp;
|
|
struct vattr vattr;
|
|
off_t foffset, size;
|
|
int error, noneg;
|
|
|
|
cred = td->td_ucred;
|
|
vp = fp->f_vnode;
|
|
foffset = foffset_lock(fp, 0);
|
|
noneg = (vp->v_type != VCHR);
|
|
error = 0;
|
|
switch (whence) {
|
|
case L_INCR:
|
|
if (noneg &&
|
|
(foffset < 0 ||
|
|
(offset > 0 && foffset > OFF_MAX - offset))) {
|
|
error = EOVERFLOW;
|
|
break;
|
|
}
|
|
offset += foffset;
|
|
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 &&
|
|
(vattr.va_size > OFF_MAX ||
|
|
(offset > 0 && vattr.va_size > OFF_MAX - offset))) {
|
|
error = EOVERFLOW;
|
|
break;
|
|
}
|
|
offset += vattr.va_size;
|
|
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;
|
|
default:
|
|
error = EINVAL;
|
|
}
|
|
if (error == 0 && noneg && offset < 0)
|
|
error = EINVAL;
|
|
if (error != 0)
|
|
goto drop;
|
|
VFS_KNOTE_UNLOCKED(vp, 0);
|
|
*(off_t *)(td->td_retval) = offset;
|
|
drop:
|
|
foffset_unlock(fp, offset, error != 0 ? FOF_NOUPDATE : 0);
|
|
return (error);
|
|
}
|