112f737245
by the inactive routine. Because the freeing causes the filesystem to be modified, the close must be held up during periods when the filesystem is suspended. For snapshots to be consistent across crashes, they must write blocks that they copy and claim those written blocks in their on-disk block pointers before the old blocks that they referenced can be allowed to be written. Close a loophole that allowed unwritten blocks to be skipped when doing ffs_sync with a request to wait for all I/O activity to be completed.
919 lines
21 KiB
C
919 lines
21 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.
|
|
*
|
|
* 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.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 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
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/fcntl.h>
|
|
#include <sys/file.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/proc.h>
|
|
#include <net/radix.h>
|
|
#include <sys/socket.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/ttycom.h>
|
|
#include <sys/conf.h>
|
|
|
|
static int vn_closefile __P((struct file *fp, struct proc *p));
|
|
static int vn_ioctl __P((struct file *fp, u_long com, caddr_t data,
|
|
struct proc *p));
|
|
static int vn_read __P((struct file *fp, struct uio *uio,
|
|
struct ucred *cred, int flags, struct proc *p));
|
|
static int vn_poll __P((struct file *fp, int events, struct ucred *cred,
|
|
struct proc *p));
|
|
static int vn_kqfilter __P((struct file *fp, struct knote *kn));
|
|
static int vn_statfile __P((struct file *fp, struct stat *sb, struct proc *p));
|
|
static int vn_write __P((struct file *fp, struct uio *uio,
|
|
struct ucred *cred, int flags, struct proc *p));
|
|
|
|
struct fileops vnops = {
|
|
vn_read, vn_write, vn_ioctl, vn_poll, vn_kqfilter,
|
|
vn_statfile, vn_closefile
|
|
};
|
|
|
|
/*
|
|
* Common code for vnode open operations.
|
|
* 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(ndp, flagp, cmode)
|
|
register struct nameidata *ndp;
|
|
int *flagp, cmode;
|
|
{
|
|
struct vnode *vp;
|
|
struct mount *mp;
|
|
struct proc *p = ndp->ni_cnd.cn_proc;
|
|
struct ucred *cred = p->p_ucred;
|
|
struct vattr vat;
|
|
struct vattr *vap = &vat;
|
|
int mode, fmode, error;
|
|
|
|
restart:
|
|
fmode = *flagp;
|
|
if (fmode & O_CREAT) {
|
|
ndp->ni_cnd.cn_nameiop = CREATE;
|
|
ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF;
|
|
if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
|
|
ndp->ni_cnd.cn_flags |= FOLLOW;
|
|
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;
|
|
}
|
|
VOP_LEASE(ndp->ni_dvp, p, cred, LEASE_WRITE);
|
|
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);
|
|
}
|
|
ASSERT_VOP_UNLOCKED(ndp->ni_dvp, "create");
|
|
ASSERT_VOP_LOCKED(ndp->ni_vp, "create");
|
|
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 =
|
|
((fmode & O_NOFOLLOW) ? NOFOLLOW : FOLLOW) | LOCKLEAF;
|
|
if ((error = namei(ndp)) != 0)
|
|
return (error);
|
|
vp = ndp->ni_vp;
|
|
}
|
|
if (vp->v_type == VLNK) {
|
|
error = EMLINK;
|
|
goto bad;
|
|
}
|
|
if (vp->v_type == VSOCK) {
|
|
error = EOPNOTSUPP;
|
|
goto bad;
|
|
}
|
|
if ((fmode & O_CREAT) == 0) {
|
|
mode = 0;
|
|
if (fmode & (FWRITE | O_TRUNC)) {
|
|
if (vp->v_type == VDIR) {
|
|
error = EISDIR;
|
|
goto bad;
|
|
}
|
|
error = vn_writechk(vp);
|
|
if (error)
|
|
goto bad;
|
|
mode |= VWRITE;
|
|
}
|
|
if (fmode & FREAD)
|
|
mode |= VREAD;
|
|
if (mode) {
|
|
error = VOP_ACCESS(vp, mode, cred, p);
|
|
if (error)
|
|
goto bad;
|
|
}
|
|
}
|
|
if ((error = VOP_OPEN(vp, fmode, cred, p)) != 0)
|
|
goto bad;
|
|
/*
|
|
* Make sure that a VM object is created for VMIO support.
|
|
*/
|
|
if (vn_canvmio(vp) == TRUE) {
|
|
if ((error = vfs_object_create(vp, p, cred)) != 0)
|
|
goto bad;
|
|
}
|
|
|
|
if (fmode & FWRITE)
|
|
vp->v_writecount++;
|
|
*flagp = fmode;
|
|
return (0);
|
|
bad:
|
|
NDFREE(ndp, NDF_ONLY_PNBUF);
|
|
vput(vp);
|
|
*flagp = fmode;
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Check for write permissions on the specified vnode.
|
|
* Prototype text segments cannot be written.
|
|
*/
|
|
int
|
|
vn_writechk(vp)
|
|
register struct vnode *vp;
|
|
{
|
|
|
|
/*
|
|
* If there's shared text associated with
|
|
* the vnode, try to free it up once. If
|
|
* we fail, we can't allow writing.
|
|
*/
|
|
if (vp->v_flag & VTEXT)
|
|
return (ETXTBSY);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Vnode close call
|
|
*/
|
|
int
|
|
vn_close(vp, flags, cred, p)
|
|
register struct vnode *vp;
|
|
int flags;
|
|
struct ucred *cred;
|
|
struct proc *p;
|
|
{
|
|
int error;
|
|
|
|
if (flags & FWRITE)
|
|
vp->v_writecount--;
|
|
error = VOP_CLOSE(vp, flags, cred, p);
|
|
/*
|
|
* XXX - In certain instances VOP_CLOSE has to do the vrele
|
|
* itself. If the vrele has been done, it will return EAGAIN
|
|
* to indicate that the vrele should not be done again. When
|
|
* this happens, we just return success. The correct thing to
|
|
* do would be to have all VOP_CLOSE instances do the vrele.
|
|
*/
|
|
if (error == EAGAIN)
|
|
return (0);
|
|
vrele(vp);
|
|
return (error);
|
|
}
|
|
|
|
static __inline
|
|
int
|
|
sequential_heuristic(struct uio *uio, struct file *fp)
|
|
{
|
|
/*
|
|
* Sequential heuristic - detect sequential operation
|
|
*/
|
|
if ((uio->uio_offset == 0 && fp->f_seqcount > 0) ||
|
|
uio->uio_offset == fp->f_nextoff) {
|
|
/*
|
|
* XXX we assume that the filesystem block size is
|
|
* the default. Not true, but still gives us a pretty
|
|
* good indicator of how sequential the read operations
|
|
* are.
|
|
*/
|
|
fp->f_seqcount += (uio->uio_resid + BKVASIZE - 1) / BKVASIZE;
|
|
if (fp->f_seqcount >= 127)
|
|
fp->f_seqcount = 127;
|
|
return(fp->f_seqcount << 16);
|
|
}
|
|
|
|
/*
|
|
* Not sequential, quick draw-down of seqcount
|
|
*/
|
|
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(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p)
|
|
enum uio_rw rw;
|
|
struct vnode *vp;
|
|
caddr_t base;
|
|
int len;
|
|
off_t offset;
|
|
enum uio_seg segflg;
|
|
int ioflg;
|
|
struct ucred *cred;
|
|
int *aresid;
|
|
struct proc *p;
|
|
{
|
|
struct uio auio;
|
|
struct iovec aiov;
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
mp = NULL;
|
|
if (rw == UIO_WRITE &&
|
|
vp->v_type != VCHR &&
|
|
(error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
|
|
return (error);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
|
|
}
|
|
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_procp = p;
|
|
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) {
|
|
vn_finished_write(mp);
|
|
VOP_UNLOCK(vp, 0, p);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode read routine.
|
|
*/
|
|
static int
|
|
vn_read(fp, uio, cred, flags, p)
|
|
struct file *fp;
|
|
struct uio *uio;
|
|
struct ucred *cred;
|
|
struct proc *p;
|
|
int flags;
|
|
{
|
|
struct vnode *vp;
|
|
int error, ioflag;
|
|
|
|
KASSERT(uio->uio_procp == p, ("uio_procp %p is not p %p",
|
|
uio->uio_procp, p));
|
|
vp = (struct vnode *)fp->f_data;
|
|
ioflag = 0;
|
|
if (fp->f_flag & FNONBLOCK)
|
|
ioflag |= IO_NDELAY;
|
|
VOP_LEASE(vp, p, cred, LEASE_READ);
|
|
vn_lock(vp, LK_SHARED | LK_NOPAUSE | LK_RETRY, p);
|
|
if ((flags & FOF_OFFSET) == 0)
|
|
uio->uio_offset = fp->f_offset;
|
|
|
|
ioflag |= sequential_heuristic(uio, fp);
|
|
|
|
error = VOP_READ(vp, uio, ioflag, cred);
|
|
if ((flags & FOF_OFFSET) == 0)
|
|
fp->f_offset = uio->uio_offset;
|
|
fp->f_nextoff = uio->uio_offset;
|
|
VOP_UNLOCK(vp, 0, p);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode write routine.
|
|
*/
|
|
static int
|
|
vn_write(fp, uio, cred, flags, p)
|
|
struct file *fp;
|
|
struct uio *uio;
|
|
struct ucred *cred;
|
|
struct proc *p;
|
|
int flags;
|
|
{
|
|
struct vnode *vp;
|
|
struct mount *mp;
|
|
int error, ioflag;
|
|
|
|
KASSERT(uio->uio_procp == p, ("uio_procp %p is not p %p",
|
|
uio->uio_procp, p));
|
|
vp = (struct vnode *)fp->f_data;
|
|
if (vp->v_type == VREG)
|
|
bwillwrite();
|
|
vp = (struct vnode *)fp->f_data; /* XXX needed? */
|
|
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_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)
|
|
return (error);
|
|
VOP_LEASE(vp, p, cred, LEASE_WRITE);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
|
|
if ((flags & FOF_OFFSET) == 0)
|
|
uio->uio_offset = fp->f_offset;
|
|
ioflag |= sequential_heuristic(uio, fp);
|
|
error = VOP_WRITE(vp, uio, ioflag, cred);
|
|
if ((flags & FOF_OFFSET) == 0)
|
|
fp->f_offset = uio->uio_offset;
|
|
fp->f_nextoff = uio->uio_offset;
|
|
VOP_UNLOCK(vp, 0, p);
|
|
vn_finished_write(mp);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode stat routine.
|
|
*/
|
|
static int
|
|
vn_statfile(fp, sb, p)
|
|
struct file *fp;
|
|
struct stat *sb;
|
|
struct proc *p;
|
|
{
|
|
struct vnode *vp = (struct vnode *)fp->f_data;
|
|
|
|
return vn_stat(vp, sb, p);
|
|
}
|
|
|
|
int
|
|
vn_stat(vp, sb, p)
|
|
struct vnode *vp;
|
|
register struct stat *sb;
|
|
struct proc *p;
|
|
{
|
|
struct vattr vattr;
|
|
register struct vattr *vap;
|
|
int error;
|
|
u_short mode;
|
|
|
|
vap = &vattr;
|
|
error = VOP_GETATTR(vp, vap, p->p_ucred, p);
|
|
if (error)
|
|
return (error);
|
|
|
|
/*
|
|
* Zero the spare stat fields
|
|
*/
|
|
sb->st_lspare = 0;
|
|
sb->st_qspare[0] = 0;
|
|
sb->st_qspare[1] = 0;
|
|
|
|
/*
|
|
* 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;
|
|
/* This is a cosmetic change, symlinks do not have a mode. */
|
|
if (vp->v_mount->mnt_flag & MNT_NOSYMFOLLOW)
|
|
sb->st_mode &= ~ACCESSPERMS; /* 0000 */
|
|
else
|
|
sb->st_mode |= ACCESSPERMS; /* 0777 */
|
|
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;
|
|
sb->st_size = vap->va_size;
|
|
sb->st_atimespec = vap->va_atime;
|
|
sb->st_mtimespec = vap->va_mtime;
|
|
sb->st_ctimespec = vap->va_ctime;
|
|
|
|
/*
|
|
* 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"
|
|
* Default to zero to catch bogus uses of this field.
|
|
*/
|
|
|
|
if (vap->va_type == VREG) {
|
|
sb->st_blksize = vap->va_blocksize;
|
|
} else if (vn_isdisk(vp, NULL)) {
|
|
sb->st_blksize = vp->v_rdev->si_bsize_best;
|
|
if (sb->st_blksize < vp->v_rdev->si_bsize_phys)
|
|
sb->st_blksize = vp->v_rdev->si_bsize_phys;
|
|
if (sb->st_blksize < BLKDEV_IOSIZE)
|
|
sb->st_blksize = BLKDEV_IOSIZE;
|
|
} else {
|
|
sb->st_blksize = 0;
|
|
}
|
|
|
|
sb->st_flags = vap->va_flags;
|
|
if (suser_xxx(p->p_ucred, 0, 0))
|
|
sb->st_gen = 0;
|
|
else
|
|
sb->st_gen = vap->va_gen;
|
|
|
|
#if (S_BLKSIZE == 512)
|
|
/* Optimize this case */
|
|
sb->st_blocks = vap->va_bytes >> 9;
|
|
#else
|
|
sb->st_blocks = vap->va_bytes / S_BLKSIZE;
|
|
#endif
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* File table vnode ioctl routine.
|
|
*/
|
|
static int
|
|
vn_ioctl(fp, com, data, p)
|
|
struct file *fp;
|
|
u_long com;
|
|
caddr_t data;
|
|
struct proc *p;
|
|
{
|
|
register struct vnode *vp = ((struct vnode *)fp->f_data);
|
|
struct vattr vattr;
|
|
int error;
|
|
|
|
switch (vp->v_type) {
|
|
|
|
case VREG:
|
|
case VDIR:
|
|
if (com == FIONREAD) {
|
|
error = VOP_GETATTR(vp, &vattr, p->p_ucred, p);
|
|
if (error)
|
|
return (error);
|
|
*(int *)data = vattr.va_size - fp->f_offset;
|
|
return (0);
|
|
}
|
|
if (com == FIONBIO || com == FIOASYNC) /* XXX */
|
|
return (0); /* XXX */
|
|
/* fall into ... */
|
|
|
|
default:
|
|
#if 0
|
|
return (ENOTTY);
|
|
#endif
|
|
case VFIFO:
|
|
case VCHR:
|
|
case VBLK:
|
|
if (com == FIODTYPE) {
|
|
if (vp->v_type != VCHR && vp->v_type != VBLK)
|
|
return (ENOTTY);
|
|
*(int *)data = devsw(vp->v_rdev)->d_flags & D_TYPEMASK;
|
|
return (0);
|
|
}
|
|
error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p);
|
|
if (error == 0 && com == TIOCSCTTY) {
|
|
|
|
/* Do nothing if reassigning same control tty */
|
|
if (p->p_session->s_ttyvp == vp)
|
|
return (0);
|
|
|
|
/* Get rid of reference to old control tty */
|
|
if (p->p_session->s_ttyvp)
|
|
vrele(p->p_session->s_ttyvp);
|
|
|
|
p->p_session->s_ttyvp = vp;
|
|
VREF(vp);
|
|
}
|
|
return (error);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* File table vnode poll routine.
|
|
*/
|
|
static int
|
|
vn_poll(fp, events, cred, p)
|
|
struct file *fp;
|
|
int events;
|
|
struct ucred *cred;
|
|
struct proc *p;
|
|
{
|
|
|
|
return (VOP_POLL(((struct vnode *)fp->f_data), events, cred, p));
|
|
}
|
|
|
|
/*
|
|
* Check that the vnode is still valid, and if so
|
|
* acquire requested lock.
|
|
*/
|
|
int
|
|
#ifndef DEBUG_LOCKS
|
|
vn_lock(vp, flags, p)
|
|
#else
|
|
debug_vn_lock(vp, flags, p, filename, line)
|
|
#endif
|
|
struct vnode *vp;
|
|
int flags;
|
|
struct proc *p;
|
|
#ifdef DEBUG_LOCKS
|
|
const char *filename;
|
|
int line;
|
|
#endif
|
|
{
|
|
int error;
|
|
|
|
do {
|
|
if ((flags & LK_INTERLOCK) == 0)
|
|
mtx_lock(&vp->v_interlock);
|
|
if ((vp->v_flag & VXLOCK) && vp->v_vxproc != curproc) {
|
|
vp->v_flag |= VXWANT;
|
|
msleep(vp, &vp->v_interlock, PINOD | PDROP,
|
|
"vn_lock", 0);
|
|
error = ENOENT;
|
|
} else {
|
|
if (vp->v_vxproc != NULL)
|
|
printf("VXLOCK interlock avoided in vn_lock\n");
|
|
#ifdef DEBUG_LOCKS
|
|
vp->filename = filename;
|
|
vp->line = line;
|
|
#endif
|
|
error = VOP_LOCK(vp,
|
|
flags | LK_NOPAUSE | LK_INTERLOCK, p);
|
|
if (error == 0)
|
|
return (error);
|
|
}
|
|
flags &= ~LK_INTERLOCK;
|
|
} while (flags & LK_RETRY);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode close routine.
|
|
*/
|
|
static int
|
|
vn_closefile(fp, p)
|
|
struct file *fp;
|
|
struct proc *p;
|
|
{
|
|
|
|
fp->f_ops = &badfileops;
|
|
return (vn_close(((struct vnode *)fp->f_data), fp->f_flag,
|
|
fp->f_cred, p));
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
int
|
|
vn_start_write(vp, mpp, flags)
|
|
struct vnode *vp;
|
|
struct mount **mpp;
|
|
int flags;
|
|
{
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
/*
|
|
* 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);
|
|
/*
|
|
* Check on status of suspension.
|
|
*/
|
|
while ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
|
|
if (flags & V_NOWAIT)
|
|
return (EWOULDBLOCK);
|
|
error = tsleep(&mp->mnt_flag, (PUSER - 1) | (flags & PCATCH),
|
|
"suspfs", 0);
|
|
if (error)
|
|
return (error);
|
|
}
|
|
if (flags & V_XSLEEP)
|
|
return (0);
|
|
mp->mnt_writeopcount++;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* 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_write_suspend_wait(vp, mp, flags)
|
|
struct vnode *vp;
|
|
struct mount *mp;
|
|
int flags;
|
|
{
|
|
int error;
|
|
|
|
if (vp != NULL) {
|
|
if ((error = VOP_GETWRITEMOUNT(vp, &mp)) != 0) {
|
|
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 == NULL || (mp->mnt_kern_flag & MNTK_SUSPENDED) == 0)
|
|
return (0);
|
|
if (flags & V_NOWAIT)
|
|
return (EWOULDBLOCK);
|
|
/*
|
|
* Wait for the suspension to finish.
|
|
*/
|
|
return (tsleep(&mp->mnt_flag, (PUSER - 1) | (flags & PCATCH),
|
|
"suspfs", 0));
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
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);
|
|
}
|
|
|
|
/*
|
|
* Request a filesystem to suspend write operations.
|
|
*/
|
|
void
|
|
vfs_write_suspend(mp)
|
|
struct mount *mp;
|
|
{
|
|
struct proc *p = curproc;
|
|
|
|
if (mp->mnt_kern_flag & MNTK_SUSPEND)
|
|
return;
|
|
mp->mnt_kern_flag |= MNTK_SUSPEND;
|
|
if (mp->mnt_writeopcount > 0)
|
|
(void) tsleep(&mp->mnt_writeopcount, PUSER - 1, "suspwt", 0);
|
|
VFS_SYNC(mp, MNT_WAIT, p->p_ucred, p);
|
|
mp->mnt_kern_flag |= MNTK_SUSPENDED;
|
|
}
|
|
|
|
/*
|
|
* Request a filesystem to resume write operations.
|
|
*/
|
|
void
|
|
vfs_write_resume(mp)
|
|
struct mount *mp;
|
|
{
|
|
|
|
if ((mp->mnt_kern_flag & MNTK_SUSPEND) == 0)
|
|
return;
|
|
mp->mnt_kern_flag &= ~(MNTK_SUSPEND | MNTK_SUSPENDED);
|
|
wakeup(&mp->mnt_writeopcount);
|
|
wakeup(&mp->mnt_flag);
|
|
}
|
|
|
|
static int
|
|
vn_kqfilter(struct file *fp, struct knote *kn)
|
|
{
|
|
|
|
return (VOP_KQFILTER(((struct vnode *)fp->f_data), 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 proc *p)
|
|
{
|
|
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_procp = p;
|
|
auio.uio_offset = 0;
|
|
auio.uio_resid = *buflen;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0)
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
|
|
|
|
/* authorize attribute retrieval as kernel */
|
|
error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, p);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0)
|
|
VOP_UNLOCK(vp, 0, p);
|
|
|
|
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 proc *p)
|
|
{
|
|
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_procp = p;
|
|
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, p);
|
|
}
|
|
|
|
/* authorize attribute setting as kernel */
|
|
error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, p);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
vn_finished_write(mp);
|
|
VOP_UNLOCK(vp, 0, p);
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
|
|
const char *attrname, struct proc *p)
|
|
{
|
|
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, p);
|
|
}
|
|
|
|
/* authorize attribute removal as kernel */
|
|
error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL, NULL, p);
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0) {
|
|
vn_finished_write(mp);
|
|
VOP_UNLOCK(vp, 0, p);
|
|
}
|
|
|
|
return (error);
|
|
}
|