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linux-2.6/fs/xfs/xfs_vnodeops.c

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/*
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_da_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_inode_item.h"
#include "xfs_itable.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_alloc.h"
#include "xfs_bmap.h"
#include "xfs_attr.h"
#include "xfs_rw.h"
#include "xfs_error.h"
#include "xfs_quota.h"
#include "xfs_utils.h"
#include "xfs_rtalloc.h"
#include "xfs_refcache.h"
#include "xfs_trans_space.h"
#include "xfs_log_priv.h"
STATIC int
xfs_open(
bhv_desc_t *bdp,
cred_t *credp)
{
int mode;
bhv_vnode_t *vp = BHV_TO_VNODE(bdp);
xfs_inode_t *ip = XFS_BHVTOI(bdp);
if (XFS_FORCED_SHUTDOWN(ip->i_mount))
return XFS_ERROR(EIO);
/*
* If it's a directory with any blocks, read-ahead block 0
* as we're almost certain to have the next operation be a read there.
*/
if (VN_ISDIR(vp) && ip->i_d.di_nextents > 0) {
mode = xfs_ilock_map_shared(ip);
if (ip->i_d.di_nextents > 0)
(void)xfs_da_reada_buf(NULL, ip, 0, XFS_DATA_FORK);
xfs_iunlock(ip, mode);
}
return 0;
}
STATIC int
xfs_close(
bhv_desc_t *bdp,
int flags,
lastclose_t lastclose,
cred_t *credp)
{
bhv_vnode_t *vp = BHV_TO_VNODE(bdp);
xfs_inode_t *ip = XFS_BHVTOI(bdp);
if (XFS_FORCED_SHUTDOWN(ip->i_mount))
return XFS_ERROR(EIO);
if (lastclose != L_TRUE || !VN_ISREG(vp))
return 0;
/*
* If we previously truncated this file and removed old data in
* the process, we want to initiate "early" writeout on the last
* close. This is an attempt to combat the notorious NULL files
* problem which is particularly noticable from a truncate down,
* buffered (re-)write (delalloc), followed by a crash. What we
* are effectively doing here is significantly reducing the time
* window where we'd otherwise be exposed to that problem.
*/
if (VUNTRUNCATE(vp) && VN_DIRTY(vp) && ip->i_delayed_blks > 0)
return bhv_vop_flush_pages(vp, 0, -1, XFS_B_ASYNC, FI_NONE);
return 0;
}
/*
* xfs_getattr
*/
STATIC int
xfs_getattr(
bhv_desc_t *bdp,
bhv_vattr_t *vap,
int flags,
cred_t *credp)
{
xfs_inode_t *ip;
xfs_mount_t *mp;
bhv_vnode_t *vp;
vp = BHV_TO_VNODE(bdp);
vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
ip = XFS_BHVTOI(bdp);
mp = ip->i_mount;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
if (!(flags & ATTR_LAZY))
xfs_ilock(ip, XFS_ILOCK_SHARED);
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
vap->va_size = XFS_ISIZE(ip);
if (vap->va_mask == XFS_AT_SIZE)
goto all_done;
vap->va_nblocks =
XFS_FSB_TO_BB(mp, ip->i_d.di_nblocks + ip->i_delayed_blks);
vap->va_nodeid = ip->i_ino;
#if XFS_BIG_INUMS
vap->va_nodeid += mp->m_inoadd;
#endif
vap->va_nlink = ip->i_d.di_nlink;
/*
* Quick exit for non-stat callers
*/
if ((vap->va_mask &
~(XFS_AT_SIZE|XFS_AT_FSID|XFS_AT_NODEID|
XFS_AT_NLINK|XFS_AT_BLKSIZE)) == 0)
goto all_done;
/*
* Copy from in-core inode.
*/
vap->va_mode = ip->i_d.di_mode;
vap->va_uid = ip->i_d.di_uid;
vap->va_gid = ip->i_d.di_gid;
vap->va_projid = ip->i_d.di_projid;
/*
* Check vnode type block/char vs. everything else.
*/
switch (ip->i_d.di_mode & S_IFMT) {
case S_IFBLK:
case S_IFCHR:
vap->va_rdev = ip->i_df.if_u2.if_rdev;
vap->va_blocksize = BLKDEV_IOSIZE;
break;
default:
vap->va_rdev = 0;
if (!(ip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
vap->va_blocksize = xfs_preferred_iosize(mp);
} else {
/*
* If the file blocks are being allocated from a
* realtime partition, then return the inode's
* realtime extent size or the realtime volume's
* extent size.
*/
vap->va_blocksize = ip->i_d.di_extsize ?
(ip->i_d.di_extsize << mp->m_sb.sb_blocklog) :
(mp->m_sb.sb_rextsize << mp->m_sb.sb_blocklog);
}
break;
}
vn_atime_to_timespec(vp, &vap->va_atime);
vap->va_mtime.tv_sec = ip->i_d.di_mtime.t_sec;
vap->va_mtime.tv_nsec = ip->i_d.di_mtime.t_nsec;
vap->va_ctime.tv_sec = ip->i_d.di_ctime.t_sec;
vap->va_ctime.tv_nsec = ip->i_d.di_ctime.t_nsec;
/*
* Exit for stat callers. See if any of the rest of the fields
* to be filled in are needed.
*/
if ((vap->va_mask &
(XFS_AT_XFLAGS|XFS_AT_EXTSIZE|XFS_AT_NEXTENTS|XFS_AT_ANEXTENTS|
XFS_AT_GENCOUNT|XFS_AT_VCODE)) == 0)
goto all_done;
/*
* Convert di_flags to xflags.
*/
vap->va_xflags = xfs_ip2xflags(ip);
/*
* Exit for inode revalidate. See if any of the rest of
* the fields to be filled in are needed.
*/
if ((vap->va_mask &
(XFS_AT_EXTSIZE|XFS_AT_NEXTENTS|XFS_AT_ANEXTENTS|
XFS_AT_GENCOUNT|XFS_AT_VCODE)) == 0)
goto all_done;
vap->va_extsize = ip->i_d.di_extsize << mp->m_sb.sb_blocklog;
vap->va_nextents =
(ip->i_df.if_flags & XFS_IFEXTENTS) ?
ip->i_df.if_bytes / sizeof(xfs_bmbt_rec_t) :
ip->i_d.di_nextents;
if (ip->i_afp)
vap->va_anextents =
(ip->i_afp->if_flags & XFS_IFEXTENTS) ?
ip->i_afp->if_bytes / sizeof(xfs_bmbt_rec_t) :
ip->i_d.di_anextents;
else
vap->va_anextents = 0;
vap->va_gen = ip->i_d.di_gen;
all_done:
if (!(flags & ATTR_LAZY))
xfs_iunlock(ip, XFS_ILOCK_SHARED);
return 0;
}
/*
* xfs_setattr
*/
int
xfs_setattr(
bhv_desc_t *bdp,
bhv_vattr_t *vap,
int flags,
cred_t *credp)
{
xfs_inode_t *ip;
xfs_trans_t *tp;
xfs_mount_t *mp;
int mask;
int code;
uint lock_flags;
uint commit_flags=0;
uid_t uid=0, iuid=0;
gid_t gid=0, igid=0;
int timeflags = 0;
bhv_vnode_t *vp;
xfs_prid_t projid=0, iprojid=0;
int mandlock_before, mandlock_after;
struct xfs_dquot *udqp, *gdqp, *olddquot1, *olddquot2;
int file_owner;
int need_iolock = 1;
vp = BHV_TO_VNODE(bdp);
vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
if (vp->v_vfsp->vfs_flag & VFS_RDONLY)
return XFS_ERROR(EROFS);
/*
* Cannot set certain attributes.
*/
mask = vap->va_mask;
if (mask & XFS_AT_NOSET) {
return XFS_ERROR(EINVAL);
}
ip = XFS_BHVTOI(bdp);
mp = ip->i_mount;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
/*
* Timestamps do not need to be logged and hence do not
* need to be done within a transaction.
*/
if (mask & XFS_AT_UPDTIMES) {
ASSERT((mask & ~XFS_AT_UPDTIMES) == 0);
timeflags = ((mask & XFS_AT_UPDATIME) ? XFS_ICHGTIME_ACC : 0) |
((mask & XFS_AT_UPDCTIME) ? XFS_ICHGTIME_CHG : 0) |
((mask & XFS_AT_UPDMTIME) ? XFS_ICHGTIME_MOD : 0);
xfs_ichgtime(ip, timeflags);
return 0;
}
olddquot1 = olddquot2 = NULL;
udqp = gdqp = NULL;
/*
* If disk quotas is on, we make sure that the dquots do exist on disk,
* before we start any other transactions. Trying to do this later
* is messy. We don't care to take a readlock to look at the ids
* in inode here, because we can't hold it across the trans_reserve.
* If the IDs do change before we take the ilock, we're covered
* because the i_*dquot fields will get updated anyway.
*/
if (XFS_IS_QUOTA_ON(mp) &&
(mask & (XFS_AT_UID|XFS_AT_GID|XFS_AT_PROJID))) {
uint qflags = 0;
if ((mask & XFS_AT_UID) && XFS_IS_UQUOTA_ON(mp)) {
uid = vap->va_uid;
qflags |= XFS_QMOPT_UQUOTA;
} else {
uid = ip->i_d.di_uid;
}
if ((mask & XFS_AT_GID) && XFS_IS_GQUOTA_ON(mp)) {
gid = vap->va_gid;
qflags |= XFS_QMOPT_GQUOTA;
} else {
gid = ip->i_d.di_gid;
}
if ((mask & XFS_AT_PROJID) && XFS_IS_PQUOTA_ON(mp)) {
projid = vap->va_projid;
qflags |= XFS_QMOPT_PQUOTA;
} else {
projid = ip->i_d.di_projid;
}
/*
* We take a reference when we initialize udqp and gdqp,
* so it is important that we never blindly double trip on
* the same variable. See xfs_create() for an example.
*/
ASSERT(udqp == NULL);
ASSERT(gdqp == NULL);
code = XFS_QM_DQVOPALLOC(mp, ip, uid, gid, projid, qflags,
&udqp, &gdqp);
if (code)
return code;
}
/*
* For the other attributes, we acquire the inode lock and
* first do an error checking pass.
*/
tp = NULL;
lock_flags = XFS_ILOCK_EXCL;
if (flags & ATTR_NOLOCK)
need_iolock = 0;
if (!(mask & XFS_AT_SIZE)) {
if ((mask != (XFS_AT_CTIME|XFS_AT_ATIME|XFS_AT_MTIME)) ||
(mp->m_flags & XFS_MOUNT_WSYNC)) {
tp = xfs_trans_alloc(mp, XFS_TRANS_SETATTR_NOT_SIZE);
commit_flags = 0;
if ((code = xfs_trans_reserve(tp, 0,
XFS_ICHANGE_LOG_RES(mp), 0,
0, 0))) {
lock_flags = 0;
goto error_return;
}
}
} else {
if (DM_EVENT_ENABLED (vp->v_vfsp, ip, DM_EVENT_TRUNCATE) &&
!(flags & ATTR_DMI)) {
int dmflags = AT_DELAY_FLAG(flags) | DM_SEM_FLAG_WR;
code = XFS_SEND_DATA(mp, DM_EVENT_TRUNCATE, vp,
vap->va_size, 0, dmflags, NULL);
if (code) {
lock_flags = 0;
goto error_return;
}
}
if (need_iolock)
lock_flags |= XFS_IOLOCK_EXCL;
}
xfs_ilock(ip, lock_flags);
/* boolean: are we the file owner? */
file_owner = (current_fsuid(credp) == ip->i_d.di_uid);
/*
* Change various properties of a file.
* Only the owner or users with CAP_FOWNER
* capability may do these things.
*/
if (mask &
(XFS_AT_MODE|XFS_AT_XFLAGS|XFS_AT_EXTSIZE|XFS_AT_UID|
XFS_AT_GID|XFS_AT_PROJID)) {
/*
* CAP_FOWNER overrides the following restrictions:
*
* The user ID of the calling process must be equal
* to the file owner ID, except in cases where the
* CAP_FSETID capability is applicable.
*/
if (!file_owner && !capable(CAP_FOWNER)) {
code = XFS_ERROR(EPERM);
goto error_return;
}
/*
* CAP_FSETID overrides the following restrictions:
*
* The effective user ID of the calling process shall match
* the file owner when setting the set-user-ID and
* set-group-ID bits on that file.
*
* The effective group ID or one of the supplementary group
* IDs of the calling process shall match the group owner of
* the file when setting the set-group-ID bit on that file
*/
if (mask & XFS_AT_MODE) {
mode_t m = 0;
if ((vap->va_mode & S_ISUID) && !file_owner)
m |= S_ISUID;
if ((vap->va_mode & S_ISGID) &&
!in_group_p((gid_t)ip->i_d.di_gid))
m |= S_ISGID;
#if 0
/* Linux allows this, Irix doesn't. */
if ((vap->va_mode & S_ISVTX) && !VN_ISDIR(vp))
m |= S_ISVTX;
#endif
if (m && !capable(CAP_FSETID))
vap->va_mode &= ~m;
}
}
/*
* Change file ownership. Must be the owner or privileged.
* If the system was configured with the "restricted_chown"
* option, the owner is not permitted to give away the file,
* and can change the group id only to a group of which he
* or she is a member.
*/
if (mask & (XFS_AT_UID|XFS_AT_GID|XFS_AT_PROJID)) {
/*
* These IDs could have changed since we last looked at them.
* But, we're assured that if the ownership did change
* while we didn't have the inode locked, inode's dquot(s)
* would have changed also.
*/
iuid = ip->i_d.di_uid;
iprojid = ip->i_d.di_projid;
igid = ip->i_d.di_gid;
gid = (mask & XFS_AT_GID) ? vap->va_gid : igid;
uid = (mask & XFS_AT_UID) ? vap->va_uid : iuid;
projid = (mask & XFS_AT_PROJID) ? (xfs_prid_t)vap->va_projid :
iprojid;
/*
* CAP_CHOWN overrides the following restrictions:
*
* If _POSIX_CHOWN_RESTRICTED is defined, this capability
* shall override the restriction that a process cannot
* change the user ID of a file it owns and the restriction
* that the group ID supplied to the chown() function
* shall be equal to either the group ID or one of the
* supplementary group IDs of the calling process.
*/
if (restricted_chown &&
(iuid != uid || (igid != gid &&
!in_group_p((gid_t)gid))) &&
!capable(CAP_CHOWN)) {
code = XFS_ERROR(EPERM);
goto error_return;
}
/*
* Do a quota reservation only if uid/projid/gid is actually
* going to change.
*/
if ((XFS_IS_UQUOTA_ON(mp) && iuid != uid) ||
(XFS_IS_PQUOTA_ON(mp) && iprojid != projid) ||
(XFS_IS_GQUOTA_ON(mp) && igid != gid)) {
ASSERT(tp);
code = XFS_QM_DQVOPCHOWNRESV(mp, tp, ip, udqp, gdqp,
capable(CAP_FOWNER) ?
XFS_QMOPT_FORCE_RES : 0);
if (code) /* out of quota */
goto error_return;
}
}
/*
* Truncate file. Must have write permission and not be a directory.
*/
if (mask & XFS_AT_SIZE) {
/* Short circuit the truncate case for zero length files */
if ((vap->va_size == 0) &&
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
(ip->i_size == 0) && (ip->i_d.di_nextents == 0)) {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
lock_flags &= ~XFS_ILOCK_EXCL;
if (mask & XFS_AT_CTIME)
xfs_ichgtime(ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
code = 0;
goto error_return;
}
if (VN_ISDIR(vp)) {
code = XFS_ERROR(EISDIR);
goto error_return;
} else if (!VN_ISREG(vp)) {
code = XFS_ERROR(EINVAL);
goto error_return;
}
/*
* Make sure that the dquots are attached to the inode.
*/
if ((code = XFS_QM_DQATTACH(mp, ip, XFS_QMOPT_ILOCKED)))
goto error_return;
}
/*
* Change file access or modified times.
*/
if (mask & (XFS_AT_ATIME|XFS_AT_MTIME)) {
if (!file_owner) {
if ((flags & ATTR_UTIME) &&
!capable(CAP_FOWNER)) {
code = XFS_ERROR(EPERM);
goto error_return;
}
}
}
/*
* Change extent size or realtime flag.
*/
if (mask & (XFS_AT_EXTSIZE|XFS_AT_XFLAGS)) {
/*
* Can't change extent size if any extents are allocated.
*/
if (ip->i_d.di_nextents && (mask & XFS_AT_EXTSIZE) &&
((ip->i_d.di_extsize << mp->m_sb.sb_blocklog) !=
vap->va_extsize) ) {
code = XFS_ERROR(EINVAL); /* EFBIG? */
goto error_return;
}
/*
* Can't change realtime flag if any extents are allocated.
*/
if ((ip->i_d.di_nextents || ip->i_delayed_blks) &&
(mask & XFS_AT_XFLAGS) &&
(ip->i_d.di_flags & XFS_DIFLAG_REALTIME) !=
(vap->va_xflags & XFS_XFLAG_REALTIME)) {
code = XFS_ERROR(EINVAL); /* EFBIG? */
goto error_return;
}
/*
* Extent size must be a multiple of the appropriate block
* size, if set at all.
*/
if ((mask & XFS_AT_EXTSIZE) && vap->va_extsize != 0) {
xfs_extlen_t size;
if ((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) ||
((mask & XFS_AT_XFLAGS) &&
(vap->va_xflags & XFS_XFLAG_REALTIME))) {
size = mp->m_sb.sb_rextsize <<
mp->m_sb.sb_blocklog;
} else {
size = mp->m_sb.sb_blocksize;
}
if (vap->va_extsize % size) {
code = XFS_ERROR(EINVAL);
goto error_return;
}
}
/*
* If realtime flag is set then must have realtime data.
*/
if ((mask & XFS_AT_XFLAGS) &&
(vap->va_xflags & XFS_XFLAG_REALTIME)) {
if ((mp->m_sb.sb_rblocks == 0) ||
(mp->m_sb.sb_rextsize == 0) ||
(ip->i_d.di_extsize % mp->m_sb.sb_rextsize)) {
code = XFS_ERROR(EINVAL);
goto error_return;
}
}
/*
* Can't modify an immutable/append-only file unless
* we have appropriate permission.
*/
if ((mask & XFS_AT_XFLAGS) &&
(ip->i_d.di_flags &
(XFS_DIFLAG_IMMUTABLE|XFS_DIFLAG_APPEND) ||
(vap->va_xflags &
(XFS_XFLAG_IMMUTABLE | XFS_XFLAG_APPEND))) &&
!capable(CAP_LINUX_IMMUTABLE)) {
code = XFS_ERROR(EPERM);
goto error_return;
}
}
/*
* Now we can make the changes. Before we join the inode
* to the transaction, if XFS_AT_SIZE is set then take care of
* the part of the truncation that must be done without the
* inode lock. This needs to be done before joining the inode
* to the transaction, because the inode cannot be unlocked
* once it is a part of the transaction.
*/
if (mask & XFS_AT_SIZE) {
code = 0;
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
if ((vap->va_size > ip->i_size) &&
(flags & ATTR_NOSIZETOK) == 0) {
code = xfs_igrow_start(ip, vap->va_size, credp);
}
xfs_iunlock(ip, XFS_ILOCK_EXCL);
vn_iowait(vp); /* wait for the completion of any pending DIOs */
if (!code)
code = xfs_itruncate_data(ip, vap->va_size);
if (code) {
ASSERT(tp == NULL);
lock_flags &= ~XFS_ILOCK_EXCL;
ASSERT(lock_flags == XFS_IOLOCK_EXCL);
goto error_return;
}
tp = xfs_trans_alloc(mp, XFS_TRANS_SETATTR_SIZE);
if ((code = xfs_trans_reserve(tp, 0,
XFS_ITRUNCATE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES,
XFS_ITRUNCATE_LOG_COUNT))) {
xfs_trans_cancel(tp, 0);
if (need_iolock)
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return code;
}
commit_flags = XFS_TRANS_RELEASE_LOG_RES;
xfs_ilock(ip, XFS_ILOCK_EXCL);
}
if (tp) {
xfs_trans_ijoin(tp, ip, lock_flags);
xfs_trans_ihold(tp, ip);
}
/* determine whether mandatory locking mode changes */
mandlock_before = MANDLOCK(vp, ip->i_d.di_mode);
/*
* Truncate file. Must have write permission and not be a directory.
*/
if (mask & XFS_AT_SIZE) {
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
if (vap->va_size > ip->i_size) {
xfs_igrow_finish(tp, ip, vap->va_size,
!(flags & ATTR_DMI));
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
} else if ((vap->va_size <= ip->i_size) ||
((vap->va_size == 0) && ip->i_d.di_nextents)) {
/*
* signal a sync transaction unless
* we're truncating an already unlinked
* file on a wsync filesystem
*/
code = xfs_itruncate_finish(&tp, ip,
(xfs_fsize_t)vap->va_size,
XFS_DATA_FORK,
((ip->i_d.di_nlink != 0 ||
!(mp->m_flags & XFS_MOUNT_WSYNC))
? 1 : 0));
if (code)
goto abort_return;
/*
* Truncated "down", so we're removing references
* to old data here - if we now delay flushing for
* a long time, we expose ourselves unduly to the
* notorious NULL files problem. So, we mark this
* vnode and flush it when the file is closed, and
* do not wait the usual (long) time for writeout.
*/
VTRUNCATE(vp);
}
/*
* Have to do this even if the file's size doesn't change.
*/
timeflags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
}
/*
* Change file access modes.
*/
if (mask & XFS_AT_MODE) {
ip->i_d.di_mode &= S_IFMT;
ip->i_d.di_mode |= vap->va_mode & ~S_IFMT;
xfs_trans_log_inode (tp, ip, XFS_ILOG_CORE);
timeflags |= XFS_ICHGTIME_CHG;
}
/*
* Change file ownership. Must be the owner or privileged.
* If the system was configured with the "restricted_chown"
* option, the owner is not permitted to give away the file,
* and can change the group id only to a group of which he
* or she is a member.
*/
if (mask & (XFS_AT_UID|XFS_AT_GID|XFS_AT_PROJID)) {
/*
* CAP_FSETID overrides the following restrictions:
*
* The set-user-ID and set-group-ID bits of a file will be
* cleared upon successful return from chown()
*/
if ((ip->i_d.di_mode & (S_ISUID|S_ISGID)) &&
!capable(CAP_FSETID)) {
ip->i_d.di_mode &= ~(S_ISUID|S_ISGID);
}
/*
* Change the ownerships and register quota modifications
* in the transaction.
*/
if (iuid != uid) {
if (XFS_IS_UQUOTA_ON(mp)) {
ASSERT(mask & XFS_AT_UID);
ASSERT(udqp);
olddquot1 = XFS_QM_DQVOPCHOWN(mp, tp, ip,
&ip->i_udquot, udqp);
}
ip->i_d.di_uid = uid;
}
if (igid != gid) {
if (XFS_IS_GQUOTA_ON(mp)) {
ASSERT(!XFS_IS_PQUOTA_ON(mp));
ASSERT(mask & XFS_AT_GID);
ASSERT(gdqp);
olddquot2 = XFS_QM_DQVOPCHOWN(mp, tp, ip,
&ip->i_gdquot, gdqp);
}
ip->i_d.di_gid = gid;
}
if (iprojid != projid) {
if (XFS_IS_PQUOTA_ON(mp)) {
ASSERT(!XFS_IS_GQUOTA_ON(mp));
ASSERT(mask & XFS_AT_PROJID);
ASSERT(gdqp);
olddquot2 = XFS_QM_DQVOPCHOWN(mp, tp, ip,
&ip->i_gdquot, gdqp);
}
ip->i_d.di_projid = projid;
/*
* We may have to rev the inode as well as
* the superblock version number since projids didn't
* exist before DINODE_VERSION_2 and SB_VERSION_NLINK.
*/
if (ip->i_d.di_version == XFS_DINODE_VERSION_1)
xfs_bump_ino_vers2(tp, ip);
}
xfs_trans_log_inode (tp, ip, XFS_ILOG_CORE);
timeflags |= XFS_ICHGTIME_CHG;
}
/*
* Change file access or modified times.
*/
if (mask & (XFS_AT_ATIME|XFS_AT_MTIME)) {
if (mask & XFS_AT_ATIME) {
ip->i_d.di_atime.t_sec = vap->va_atime.tv_sec;
ip->i_d.di_atime.t_nsec = vap->va_atime.tv_nsec;
ip->i_update_core = 1;
timeflags &= ~XFS_ICHGTIME_ACC;
}
if (mask & XFS_AT_MTIME) {
ip->i_d.di_mtime.t_sec = vap->va_mtime.tv_sec;
ip->i_d.di_mtime.t_nsec = vap->va_mtime.tv_nsec;
timeflags &= ~XFS_ICHGTIME_MOD;
timeflags |= XFS_ICHGTIME_CHG;
}
if (tp && (flags & ATTR_UTIME))
xfs_trans_log_inode (tp, ip, XFS_ILOG_CORE);
}
/*
* Change XFS-added attributes.
*/
if (mask & (XFS_AT_EXTSIZE|XFS_AT_XFLAGS)) {
if (mask & XFS_AT_EXTSIZE) {
/*
* Converting bytes to fs blocks.
*/
ip->i_d.di_extsize = vap->va_extsize >>
mp->m_sb.sb_blocklog;
}
if (mask & XFS_AT_XFLAGS) {
uint di_flags;
/* can't set PREALLOC this way, just preserve it */
di_flags = (ip->i_d.di_flags & XFS_DIFLAG_PREALLOC);
if (vap->va_xflags & XFS_XFLAG_IMMUTABLE)
di_flags |= XFS_DIFLAG_IMMUTABLE;
if (vap->va_xflags & XFS_XFLAG_APPEND)
di_flags |= XFS_DIFLAG_APPEND;
if (vap->va_xflags & XFS_XFLAG_SYNC)
di_flags |= XFS_DIFLAG_SYNC;
if (vap->va_xflags & XFS_XFLAG_NOATIME)
di_flags |= XFS_DIFLAG_NOATIME;
if (vap->va_xflags & XFS_XFLAG_NODUMP)
di_flags |= XFS_DIFLAG_NODUMP;
if (vap->va_xflags & XFS_XFLAG_PROJINHERIT)
di_flags |= XFS_DIFLAG_PROJINHERIT;
if (vap->va_xflags & XFS_XFLAG_NODEFRAG)
di_flags |= XFS_DIFLAG_NODEFRAG;
if ((ip->i_d.di_mode & S_IFMT) == S_IFDIR) {
if (vap->va_xflags & XFS_XFLAG_RTINHERIT)
di_flags |= XFS_DIFLAG_RTINHERIT;
if (vap->va_xflags & XFS_XFLAG_NOSYMLINKS)
di_flags |= XFS_DIFLAG_NOSYMLINKS;
if (vap->va_xflags & XFS_XFLAG_EXTSZINHERIT)
di_flags |= XFS_DIFLAG_EXTSZINHERIT;
} else if ((ip->i_d.di_mode & S_IFMT) == S_IFREG) {
if (vap->va_xflags & XFS_XFLAG_REALTIME) {
di_flags |= XFS_DIFLAG_REALTIME;
ip->i_iocore.io_flags |= XFS_IOCORE_RT;
} else {
ip->i_iocore.io_flags &= ~XFS_IOCORE_RT;
}
if (vap->va_xflags & XFS_XFLAG_EXTSIZE)
di_flags |= XFS_DIFLAG_EXTSIZE;
}
ip->i_d.di_flags = di_flags;
}
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
timeflags |= XFS_ICHGTIME_CHG;
}
/*
* Change file inode change time only if XFS_AT_CTIME set
* AND we have been called by a DMI function.
*/
if ( (flags & ATTR_DMI) && (mask & XFS_AT_CTIME) ) {
ip->i_d.di_ctime.t_sec = vap->va_ctime.tv_sec;
ip->i_d.di_ctime.t_nsec = vap->va_ctime.tv_nsec;
ip->i_update_core = 1;
timeflags &= ~XFS_ICHGTIME_CHG;
}
/*
* Send out timestamp changes that need to be set to the
* current time. Not done when called by a DMI function.
*/
if (timeflags && !(flags & ATTR_DMI))
xfs_ichgtime(ip, timeflags);
XFS_STATS_INC(xs_ig_attrchg);
/*
* If this is a synchronous mount, make sure that the
* transaction goes to disk before returning to the user.
* This is slightly sub-optimal in that truncates require
* two sync transactions instead of one for wsync filesystems.
* One for the truncate and one for the timestamps since we
* don't want to change the timestamps unless we're sure the
* truncate worked. Truncates are less than 1% of the laddis
* mix so this probably isn't worth the trouble to optimize.
*/
code = 0;
if (tp) {
if (mp->m_flags & XFS_MOUNT_WSYNC)
xfs_trans_set_sync(tp);
code = xfs_trans_commit(tp, commit_flags);
}
/*
* If the (regular) file's mandatory locking mode changed, then
* notify the vnode. We do this under the inode lock to prevent
* racing calls to vop_vnode_change.
*/
mandlock_after = MANDLOCK(vp, ip->i_d.di_mode);
if (mandlock_before != mandlock_after) {
bhv_vop_vnode_change(vp, VCHANGE_FLAGS_ENF_LOCKING,
mandlock_after);
}
xfs_iunlock(ip, lock_flags);
/*
* Release any dquot(s) the inode had kept before chown.
*/
XFS_QM_DQRELE(mp, olddquot1);
XFS_QM_DQRELE(mp, olddquot2);
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
if (code) {
return code;
}
if (DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_ATTRIBUTE) &&
!(flags & ATTR_DMI)) {
(void) XFS_SEND_NAMESP(mp, DM_EVENT_ATTRIBUTE, vp, DM_RIGHT_NULL,
NULL, DM_RIGHT_NULL, NULL, NULL,
0, 0, AT_DELAY_FLAG(flags));
}
return 0;
abort_return:
commit_flags |= XFS_TRANS_ABORT;
/* FALLTHROUGH */
error_return:
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
if (tp) {
xfs_trans_cancel(tp, commit_flags);
}
if (lock_flags != 0) {
xfs_iunlock(ip, lock_flags);
}
return code;
}
/*
* xfs_access
* Null conversion from vnode mode bits to inode mode bits, as in efs.
*/
STATIC int
xfs_access(
bhv_desc_t *bdp,
int mode,
cred_t *credp)
{
xfs_inode_t *ip;
int error;
vn_trace_entry(BHV_TO_VNODE(bdp), __FUNCTION__,
(inst_t *)__return_address);
ip = XFS_BHVTOI(bdp);
xfs_ilock(ip, XFS_ILOCK_SHARED);
error = xfs_iaccess(ip, mode, credp);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
return error;
}
/*
* The maximum pathlen is 1024 bytes. Since the minimum file system
* blocksize is 512 bytes, we can get a max of 2 extents back from
* bmapi.
*/
#define SYMLINK_MAPS 2
/*
* xfs_readlink
*
*/
STATIC int
xfs_readlink(
bhv_desc_t *bdp,
uio_t *uiop,
int ioflags,
cred_t *credp)
{
xfs_inode_t *ip;
int count;
xfs_off_t offset;
int pathlen;
bhv_vnode_t *vp;
int error = 0;
xfs_mount_t *mp;
int nmaps;
xfs_bmbt_irec_t mval[SYMLINK_MAPS];
xfs_daddr_t d;
int byte_cnt;
int n;
xfs_buf_t *bp;
vp = BHV_TO_VNODE(bdp);
vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
ip = XFS_BHVTOI(bdp);
mp = ip->i_mount;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
xfs_ilock(ip, XFS_ILOCK_SHARED);
ASSERT((ip->i_d.di_mode & S_IFMT) == S_IFLNK);
offset = uiop->uio_offset;
count = uiop->uio_resid;
if (offset < 0) {
error = XFS_ERROR(EINVAL);
goto error_return;
}
if (count <= 0) {
error = 0;
goto error_return;
}
/*
* See if the symlink is stored inline.
*/
pathlen = (int)ip->i_d.di_size;
if (ip->i_df.if_flags & XFS_IFINLINE) {
error = xfs_uio_read(ip->i_df.if_u1.if_data, pathlen, uiop);
}
else {
/*
* Symlink not inline. Call bmap to get it in.
*/
nmaps = SYMLINK_MAPS;
error = xfs_bmapi(NULL, ip, 0, XFS_B_TO_FSB(mp, pathlen),
0, NULL, 0, mval, &nmaps, NULL, NULL);
if (error) {
goto error_return;
}
for (n = 0; n < nmaps; n++) {
d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
bp = xfs_buf_read(mp->m_ddev_targp, d,
BTOBB(byte_cnt), 0);
error = XFS_BUF_GETERROR(bp);
if (error) {
xfs_ioerror_alert("xfs_readlink",
ip->i_mount, bp, XFS_BUF_ADDR(bp));
xfs_buf_relse(bp);
goto error_return;
}
if (pathlen < byte_cnt)
byte_cnt = pathlen;
pathlen -= byte_cnt;
error = xfs_uio_read(XFS_BUF_PTR(bp), byte_cnt, uiop);
xfs_buf_relse (bp);
}
}
error_return:
xfs_iunlock(ip, XFS_ILOCK_SHARED);
return error;
}
/*
* xfs_fsync
*
* This is called to sync the inode and its data out to disk.
* We need to hold the I/O lock while flushing the data, and
* the inode lock while flushing the inode. The inode lock CANNOT
* be held while flushing the data, so acquire after we're done
* with that.
*/
STATIC int
xfs_fsync(
bhv_desc_t *bdp,
int flag,
cred_t *credp,
xfs_off_t start,
xfs_off_t stop)
{
xfs_inode_t *ip;
xfs_trans_t *tp;
int error;
int log_flushed = 0, changed = 1;
vn_trace_entry(BHV_TO_VNODE(bdp),
__FUNCTION__, (inst_t *)__return_address);
ip = XFS_BHVTOI(bdp);
ASSERT(start >= 0 && stop >= -1);
if (XFS_FORCED_SHUTDOWN(ip->i_mount))
return XFS_ERROR(EIO);
/*
* We always need to make sure that the required inode state
* is safe on disk. The vnode might be clean but because
* of committed transactions that haven't hit the disk yet.
* Likewise, there could be unflushed non-transactional
* changes to the inode core that have to go to disk.
*
* The following code depends on one assumption: that
* any transaction that changes an inode logs the core
* because it has to change some field in the inode core
* (typically nextents or nblocks). That assumption
* implies that any transactions against an inode will
* catch any non-transactional updates. If inode-altering
* transactions exist that violate this assumption, the
* code breaks. Right now, it figures that if the involved
* update_* field is clear and the inode is unpinned, the
* inode is clean. Either it's been flushed or it's been
* committed and the commit has hit the disk unpinning the inode.
* (Note that xfs_inode_item_format() called at commit clears
* the update_* fields.)
*/
xfs_ilock(ip, XFS_ILOCK_SHARED);
/* If we are flushing data then we care about update_size
* being set, otherwise we care about update_core
*/
if ((flag & FSYNC_DATA) ?
(ip->i_update_size == 0) :
(ip->i_update_core == 0)) {
/*
* Timestamps/size haven't changed since last inode
* flush or inode transaction commit. That means
* either nothing got written or a transaction
* committed which caught the updates. If the
* latter happened and the transaction hasn't
* hit the disk yet, the inode will be still
* be pinned. If it is, force the log.
*/
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (xfs_ipincount(ip)) {
_xfs_log_force(ip->i_mount, (xfs_lsn_t)0,
XFS_LOG_FORCE |
((flag & FSYNC_WAIT)
? XFS_LOG_SYNC : 0),
&log_flushed);
} else {
/*
* If the inode is not pinned and nothing
* has changed we don't need to flush the
* cache.
*/
changed = 0;
}
error = 0;
} else {
/*
* Kick off a transaction to log the inode
* core to get the updates. Make it
* sync if FSYNC_WAIT is passed in (which
* is done by everybody but specfs). The
* sync transaction will also force the log.
*/
xfs_iunlock(ip, XFS_ILOCK_SHARED);
tp = xfs_trans_alloc(ip->i_mount, XFS_TRANS_FSYNC_TS);
if ((error = xfs_trans_reserve(tp, 0,
XFS_FSYNC_TS_LOG_RES(ip->i_mount),
0, 0, 0))) {
xfs_trans_cancel(tp, 0);
return error;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
/*
* Note - it's possible that we might have pushed
* ourselves out of the way during trans_reserve
* which would flush the inode. But there's no
* guarantee that the inode buffer has actually
* gone out yet (it's delwri). Plus the buffer
* could be pinned anyway if it's part of an
* inode in another recent transaction. So we
* play it safe and fire off the transaction anyway.
*/
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
if (flag & FSYNC_WAIT)
xfs_trans_set_sync(tp);
error = _xfs_trans_commit(tp, 0, &log_flushed);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
}
if ((ip->i_mount->m_flags & XFS_MOUNT_BARRIER) && changed) {
/*
* If the log write didn't issue an ordered tag we need
* to flush the disk cache for the data device now.
*/
if (!log_flushed)
xfs_blkdev_issue_flush(ip->i_mount->m_ddev_targp);
/*
* If this inode is on the RT dev we need to flush that
* cache as well.
*/
if (ip->i_d.di_flags & XFS_DIFLAG_REALTIME)
xfs_blkdev_issue_flush(ip->i_mount->m_rtdev_targp);
}
return error;
}
/*
* This is called by xfs_inactive to free any blocks beyond eof
* when the link count isn't zero and by xfs_dm_punch_hole() when
* punching a hole to EOF.
*/
int
xfs_free_eofblocks(
xfs_mount_t *mp,
xfs_inode_t *ip,
int flags)
{
xfs_trans_t *tp;
int error;
xfs_fileoff_t end_fsb;
xfs_fileoff_t last_fsb;
xfs_filblks_t map_len;
int nimaps;
xfs_bmbt_irec_t imap;
int use_iolock = (flags & XFS_FREE_EOF_LOCK);
/*
* Figure out if there are any blocks beyond the end
* of the file. If not, then there is nothing to do.
*/
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
end_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)ip->i_size));
last_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
map_len = last_fsb - end_fsb;
if (map_len <= 0)
return 0;
nimaps = 1;
xfs_ilock(ip, XFS_ILOCK_SHARED);
error = XFS_BMAPI(mp, NULL, &ip->i_iocore, end_fsb, map_len, 0,
NULL, 0, &imap, &nimaps, NULL, NULL);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (!error && (nimaps != 0) &&
(imap.br_startblock != HOLESTARTBLOCK ||
ip->i_delayed_blks)) {
/*
* Attach the dquots to the inode up front.
*/
if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
return error;
/*
* There are blocks after the end of file.
* Free them up now by truncating the file to
* its current size.
*/
tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
/*
* Do the xfs_itruncate_start() call before
* reserving any log space because
* itruncate_start will call into the buffer
* cache and we can't
* do that within a transaction.
*/
if (use_iolock)
xfs_ilock(ip, XFS_IOLOCK_EXCL);
error = xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE,
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
ip->i_size);
if (error) {
if (use_iolock)
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
error = xfs_trans_reserve(tp, 0,
XFS_ITRUNCATE_LOG_RES(mp),
0, XFS_TRANS_PERM_LOG_RES,
XFS_ITRUNCATE_LOG_COUNT);
if (error) {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
xfs_trans_cancel(tp, 0);
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip,
XFS_IOLOCK_EXCL |
XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
error = xfs_itruncate_finish(&tp, ip,
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
ip->i_size,
XFS_DATA_FORK,
0);
/*
* If we get an error at this point we
* simply don't bother truncating the file.
*/
if (error) {
xfs_trans_cancel(tp,
(XFS_TRANS_RELEASE_LOG_RES |
XFS_TRANS_ABORT));
} else {
error = xfs_trans_commit(tp,
XFS_TRANS_RELEASE_LOG_RES);
}
xfs_iunlock(ip, (use_iolock ? (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)
: XFS_ILOCK_EXCL));
}
return error;
}
/*
* Free a symlink that has blocks associated with it.
*/
STATIC int
xfs_inactive_symlink_rmt(
xfs_inode_t *ip,
xfs_trans_t **tpp)
{
xfs_buf_t *bp;
int committed;
int done;
int error;
xfs_fsblock_t first_block;
xfs_bmap_free_t free_list;
int i;
xfs_mount_t *mp;
xfs_bmbt_irec_t mval[SYMLINK_MAPS];
int nmaps;
xfs_trans_t *ntp;
int size;
xfs_trans_t *tp;
tp = *tpp;
mp = ip->i_mount;
ASSERT(ip->i_d.di_size > XFS_IFORK_DSIZE(ip));
/*
* We're freeing a symlink that has some
* blocks allocated to it. Free the
* blocks here. We know that we've got
* either 1 or 2 extents and that we can
* free them all in one bunmapi call.
*/
ASSERT(ip->i_d.di_nextents > 0 && ip->i_d.di_nextents <= 2);
if ((error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_ITRUNCATE_LOG_COUNT))) {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
xfs_trans_cancel(tp, 0);
*tpp = NULL;
return error;
}
/*
* Lock the inode, fix the size, and join it to the transaction.
* Hold it so in the normal path, we still have it locked for
* the second transaction. In the error paths we need it
* held so the cancel won't rele it, see below.
*/
xfs_ilock(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
size = (int)ip->i_d.di_size;
ip->i_d.di_size = 0;
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
xfs_trans_ihold(tp, ip);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
/*
* Find the block(s) so we can inval and unmap them.
*/
done = 0;
XFS_BMAP_INIT(&free_list, &first_block);
nmaps = ARRAY_SIZE(mval);
if ((error = xfs_bmapi(tp, ip, 0, XFS_B_TO_FSB(mp, size),
XFS_BMAPI_METADATA, &first_block, 0, mval, &nmaps,
&free_list, NULL)))
goto error0;
/*
* Invalidate the block(s).
*/
for (i = 0; i < nmaps; i++) {
bp = xfs_trans_get_buf(tp, mp->m_ddev_targp,
XFS_FSB_TO_DADDR(mp, mval[i].br_startblock),
XFS_FSB_TO_BB(mp, mval[i].br_blockcount), 0);
xfs_trans_binval(tp, bp);
}
/*
* Unmap the dead block(s) to the free_list.
*/
if ((error = xfs_bunmapi(tp, ip, 0, size, XFS_BMAPI_METADATA, nmaps,
&first_block, &free_list, NULL, &done)))
goto error1;
ASSERT(done);
/*
* Commit the first transaction. This logs the EFI and the inode.
*/
if ((error = xfs_bmap_finish(&tp, &free_list, &committed)))
goto error1;
/*
* The transaction must have been committed, since there were
* actually extents freed by xfs_bunmapi. See xfs_bmap_finish.
* The new tp has the extent freeing and EFDs.
*/
ASSERT(committed);
/*
* The first xact was committed, so add the inode to the new one.
* Mark it dirty so it will be logged and moved forward in the log as
* part of every commit.
*/
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
xfs_trans_ihold(tp, ip);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
/*
* Get a new, empty transaction to return to our caller.
*/
ntp = xfs_trans_dup(tp);
/*
* Commit the transaction containing extent freeing and EFDs.
* If we get an error on the commit here or on the reserve below,
* we need to unlock the inode since the new transaction doesn't
* have the inode attached.
*/
error = xfs_trans_commit(tp, 0);
tp = ntp;
if (error) {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
goto error0;
}
/*
* Remove the memory for extent descriptions (just bookkeeping).
*/
if (ip->i_df.if_bytes)
xfs_idata_realloc(ip, -ip->i_df.if_bytes, XFS_DATA_FORK);
ASSERT(ip->i_df.if_bytes == 0);
/*
* Put an itruncate log reservation in the new transaction
* for our caller.
*/
if ((error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_ITRUNCATE_LOG_COUNT))) {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
goto error0;
}
/*
* Return with the inode locked but not joined to the transaction.
*/
*tpp = tp;
return 0;
error1:
xfs_bmap_cancel(&free_list);
error0:
/*
* Have to come here with the inode locked and either
* (held and in the transaction) or (not in the transaction).
* If the inode isn't held then cancel would iput it, but
* that's wrong since this is inactive and the vnode ref
* count is 0 already.
* Cancel won't do anything to the inode if held, but it still
* needs to be locked until the cancel is done, if it was
* joined to the transaction.
*/
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
xfs_iunlock(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
*tpp = NULL;
return error;
}
STATIC int
xfs_inactive_symlink_local(
xfs_inode_t *ip,
xfs_trans_t **tpp)
{
int error;
ASSERT(ip->i_d.di_size <= XFS_IFORK_DSIZE(ip));
/*
* We're freeing a symlink which fit into
* the inode. Just free the memory used
* to hold the old symlink.
*/
error = xfs_trans_reserve(*tpp, 0,
XFS_ITRUNCATE_LOG_RES(ip->i_mount),
0, XFS_TRANS_PERM_LOG_RES,
XFS_ITRUNCATE_LOG_COUNT);
if (error) {
xfs_trans_cancel(*tpp, 0);
*tpp = NULL;
return error;
}
xfs_ilock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
/*
* Zero length symlinks _can_ exist.
*/
if (ip->i_df.if_bytes > 0) {
xfs_idata_realloc(ip,
-(ip->i_df.if_bytes),
XFS_DATA_FORK);
ASSERT(ip->i_df.if_bytes == 0);
}
return 0;
}
STATIC int
xfs_inactive_attrs(
xfs_inode_t *ip,
xfs_trans_t **tpp)
{
xfs_trans_t *tp;
int error;
xfs_mount_t *mp;
ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE));
tp = *tpp;
mp = ip->i_mount;
ASSERT(ip->i_d.di_forkoff != 0);
xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
error = xfs_attr_inactive(ip);
if (error) {
*tpp = NULL;
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error; /* goto out */
}
tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
error = xfs_trans_reserve(tp, 0,
XFS_IFREE_LOG_RES(mp),
0, XFS_TRANS_PERM_LOG_RES,
XFS_INACTIVE_LOG_COUNT);
if (error) {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
xfs_trans_cancel(tp, 0);
*tpp = NULL;
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
xfs_idestroy_fork(ip, XFS_ATTR_FORK);
ASSERT(ip->i_d.di_anextents == 0);
*tpp = tp;
return 0;
}
STATIC int
xfs_release(
bhv_desc_t *bdp)
{
xfs_inode_t *ip;
bhv_vnode_t *vp;
xfs_mount_t *mp;
int error;
vp = BHV_TO_VNODE(bdp);
ip = XFS_BHVTOI(bdp);
mp = ip->i_mount;
if (!VN_ISREG(vp) || (ip->i_d.di_mode == 0))
return 0;
/* If this is a read-only mount, don't do this (would generate I/O) */
if (vp->v_vfsp->vfs_flag & VFS_RDONLY)
return 0;
#ifdef HAVE_REFCACHE
/* If we are in the NFS reference cache then don't do this now */
if (ip->i_refcache)
return 0;
#endif
if (ip->i_d.di_nlink != 0) {
if ((((ip->i_d.di_mode & S_IFMT) == S_IFREG) &&
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
((ip->i_size > 0) || (VN_CACHED(vp) > 0 ||
ip->i_delayed_blks > 0)) &&
(ip->i_df.if_flags & XFS_IFEXTENTS)) &&
(!(ip->i_d.di_flags &
(XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)))) {
error = xfs_free_eofblocks(mp, ip, XFS_FREE_EOF_LOCK);
if (error)
return error;
/* Update linux inode block count after free above */
vn_to_inode(vp)->i_blocks = XFS_FSB_TO_BB(mp,
ip->i_d.di_nblocks + ip->i_delayed_blks);
}
}
return 0;
}
/*
* xfs_inactive
*
* This is called when the vnode reference count for the vnode
* goes to zero. If the file has been unlinked, then it must
* now be truncated. Also, we clear all of the read-ahead state
* kept for the inode here since the file is now closed.
*/
STATIC int
xfs_inactive(
bhv_desc_t *bdp,
cred_t *credp)
{
xfs_inode_t *ip;
bhv_vnode_t *vp;
xfs_bmap_free_t free_list;
xfs_fsblock_t first_block;
int committed;
xfs_trans_t *tp;
xfs_mount_t *mp;
int error;
int truncate;
vp = BHV_TO_VNODE(bdp);
vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
ip = XFS_BHVTOI(bdp);
/*
* If the inode is already free, then there can be nothing
* to clean up here.
*/
if (ip->i_d.di_mode == 0 || VN_BAD(vp)) {
ASSERT(ip->i_df.if_real_bytes == 0);
ASSERT(ip->i_df.if_broot_bytes == 0);
return VN_INACTIVE_CACHE;
}
/*
* Only do a truncate if it's a regular file with
* some actual space in it. It's OK to look at the
* inode's fields without the lock because we're the
* only one with a reference to the inode.
*/
truncate = ((ip->i_d.di_nlink == 0) &&
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
((ip->i_d.di_size != 0) || (ip->i_size != 0) ||
(ip->i_d.di_nextents > 0) || (ip->i_delayed_blks > 0)) &&
((ip->i_d.di_mode & S_IFMT) == S_IFREG));
mp = ip->i_mount;
if (ip->i_d.di_nlink == 0 &&
DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_DESTROY)) {
(void) XFS_SEND_DESTROY(mp, vp, DM_RIGHT_NULL);
}
error = 0;
/* If this is a read-only mount, don't do this (would generate I/O) */
if (vp->v_vfsp->vfs_flag & VFS_RDONLY)
goto out;
if (ip->i_d.di_nlink != 0) {
if ((((ip->i_d.di_mode & S_IFMT) == S_IFREG) &&
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
((ip->i_size > 0) || (VN_CACHED(vp) > 0 ||
ip->i_delayed_blks > 0)) &&
(ip->i_df.if_flags & XFS_IFEXTENTS) &&
(!(ip->i_d.di_flags &
(XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) ||
(ip->i_delayed_blks != 0)))) {
error = xfs_free_eofblocks(mp, ip, XFS_FREE_EOF_LOCK);
if (error)
return VN_INACTIVE_CACHE;
/* Update linux inode block count after free above */
vn_to_inode(vp)->i_blocks = XFS_FSB_TO_BB(mp,
ip->i_d.di_nblocks + ip->i_delayed_blks);
}
goto out;
}
ASSERT(ip->i_d.di_nlink == 0);
if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
return VN_INACTIVE_CACHE;
tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
if (truncate) {
/*
* Do the xfs_itruncate_start() call before
* reserving any log space because itruncate_start
* will call into the buffer cache and we can't
* do that within a transaction.
*/
xfs_ilock(ip, XFS_IOLOCK_EXCL);
error = xfs_itruncate_start(ip, XFS_ITRUNC_DEFINITE, 0);
if (error) {
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return VN_INACTIVE_CACHE;
}
error = xfs_trans_reserve(tp, 0,
XFS_ITRUNCATE_LOG_RES(mp),
0, XFS_TRANS_PERM_LOG_RES,
XFS_ITRUNCATE_LOG_COUNT);
if (error) {
/* Don't call itruncate_cleanup */
ASSERT(XFS_FORCED_SHUTDOWN(mp));
xfs_trans_cancel(tp, 0);
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return VN_INACTIVE_CACHE;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
/*
* normally, we have to run xfs_itruncate_finish sync.
* But if filesystem is wsync and we're in the inactive
* path, then we know that nlink == 0, and that the
* xaction that made nlink == 0 is permanently committed
* since xfs_remove runs as a synchronous transaction.
*/
error = xfs_itruncate_finish(&tp, ip, 0, XFS_DATA_FORK,
(!(mp->m_flags & XFS_MOUNT_WSYNC) ? 1 : 0));
if (error) {
xfs_trans_cancel(tp,
XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
xfs_iunlock(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
return VN_INACTIVE_CACHE;
}
} else if ((ip->i_d.di_mode & S_IFMT) == S_IFLNK) {
/*
* If we get an error while cleaning up a
* symlink we bail out.
*/
error = (ip->i_d.di_size > XFS_IFORK_DSIZE(ip)) ?
xfs_inactive_symlink_rmt(ip, &tp) :
xfs_inactive_symlink_local(ip, &tp);
if (error) {
ASSERT(tp == NULL);
return VN_INACTIVE_CACHE;
}
xfs_trans_ijoin(tp, ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
} else {
error = xfs_trans_reserve(tp, 0,
XFS_IFREE_LOG_RES(mp),
0, XFS_TRANS_PERM_LOG_RES,
XFS_INACTIVE_LOG_COUNT);
if (error) {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
xfs_trans_cancel(tp, 0);
return VN_INACTIVE_CACHE;
}
xfs_ilock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
}
/*
* If there are attributes associated with the file
* then blow them away now. The code calls a routine
* that recursively deconstructs the attribute fork.
* We need to just commit the current transaction
* because we can't use it for xfs_attr_inactive().
*/
if (ip->i_d.di_anextents > 0) {
error = xfs_inactive_attrs(ip, &tp);
/*
* If we got an error, the transaction is already
* cancelled, and the inode is unlocked. Just get out.
*/
if (error)
return VN_INACTIVE_CACHE;
} else if (ip->i_afp) {
xfs_idestroy_fork(ip, XFS_ATTR_FORK);
}
/*
* Free the inode.
*/
XFS_BMAP_INIT(&free_list, &first_block);
error = xfs_ifree(tp, ip, &free_list);
if (error) {
/*
* If we fail to free the inode, shut down. The cancel
* might do that, we need to make sure. Otherwise the
* inode might be lost for a long time or forever.
*/
if (!XFS_FORCED_SHUTDOWN(mp)) {
cmn_err(CE_NOTE,
"xfs_inactive: xfs_ifree() returned an error = %d on %s",
error, mp->m_fsname);
xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
}
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
} else {
/*
* Credit the quota account(s). The inode is gone.
*/
XFS_TRANS_MOD_DQUOT_BYINO(mp, tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
/*
* Just ignore errors at this point. There is
* nothing we can do except to try to keep going.
*/
(void) xfs_bmap_finish(&tp, &free_list, &committed);
(void) xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
}
/*
* Release the dquots held by inode, if any.
*/
XFS_QM_DQDETACH(mp, ip);
xfs_iunlock(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
out:
return VN_INACTIVE_CACHE;
}
/*
* xfs_lookup
*/
STATIC int
xfs_lookup(
bhv_desc_t *dir_bdp,
bhv_vname_t *dentry,
bhv_vnode_t **vpp,
int flags,
bhv_vnode_t *rdir,
cred_t *credp)
{
xfs_inode_t *dp, *ip;
xfs_ino_t e_inum;
int error;
uint lock_mode;
bhv_vnode_t *dir_vp;
dir_vp = BHV_TO_VNODE(dir_bdp);
vn_trace_entry(dir_vp, __FUNCTION__, (inst_t *)__return_address);
dp = XFS_BHVTOI(dir_bdp);
if (XFS_FORCED_SHUTDOWN(dp->i_mount))
return XFS_ERROR(EIO);
lock_mode = xfs_ilock_map_shared(dp);
error = xfs_dir_lookup_int(dir_bdp, lock_mode, dentry, &e_inum, &ip);
if (!error) {
*vpp = XFS_ITOV(ip);
ITRACE(ip);
}
xfs_iunlock_map_shared(dp, lock_mode);
return error;
}
/*
* xfs_create (create a new file).
*/
STATIC int
xfs_create(
bhv_desc_t *dir_bdp,
bhv_vname_t *dentry,
bhv_vattr_t *vap,
bhv_vnode_t **vpp,
cred_t *credp)
{
char *name = VNAME(dentry);
bhv_vnode_t *dir_vp;
xfs_inode_t *dp, *ip;
bhv_vnode_t *vp = NULL;
xfs_trans_t *tp;
xfs_mount_t *mp;
xfs_dev_t rdev;
int error;
xfs_bmap_free_t free_list;
xfs_fsblock_t first_block;
boolean_t dp_joined_to_trans;
int dm_event_sent = 0;
uint cancel_flags;
int committed;
xfs_prid_t prid;
struct xfs_dquot *udqp, *gdqp;
uint resblks;
int dm_di_mode;
int namelen;
ASSERT(!*vpp);
dir_vp = BHV_TO_VNODE(dir_bdp);
vn_trace_entry(dir_vp, __FUNCTION__, (inst_t *)__return_address);
dp = XFS_BHVTOI(dir_bdp);
mp = dp->i_mount;
dm_di_mode = vap->va_mode;
namelen = VNAMELEN(dentry);
if (DM_EVENT_ENABLED(dir_vp->v_vfsp, dp, DM_EVENT_CREATE)) {
error = XFS_SEND_NAMESP(mp, DM_EVENT_CREATE,
dir_vp, DM_RIGHT_NULL, NULL,
DM_RIGHT_NULL, name, NULL,
dm_di_mode, 0, 0);
if (error)
return error;
dm_event_sent = 1;
}
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
/* Return through std_return after this point. */
udqp = gdqp = NULL;
if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
prid = dp->i_d.di_projid;
else if (vap->va_mask & XFS_AT_PROJID)
prid = (xfs_prid_t)vap->va_projid;
else
prid = (xfs_prid_t)dfltprid;
/*
* Make sure that we have allocated dquot(s) on disk.
*/
error = XFS_QM_DQVOPALLOC(mp, dp,
current_fsuid(credp), current_fsgid(credp), prid,
XFS_QMOPT_QUOTALL|XFS_QMOPT_INHERIT, &udqp, &gdqp);
if (error)
goto std_return;
ip = NULL;
dp_joined_to_trans = B_FALSE;
tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE);
cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
resblks = XFS_CREATE_SPACE_RES(mp, namelen);
/*
* Initially assume that the file does not exist and
* reserve the resources for that case. If that is not
* the case we'll drop the one we have and get a more
* appropriate transaction later.
*/
error = xfs_trans_reserve(tp, resblks, XFS_CREATE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_CREATE_LOG_COUNT);
if (error == ENOSPC) {
resblks = 0;
error = xfs_trans_reserve(tp, 0, XFS_CREATE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_CREATE_LOG_COUNT);
}
if (error) {
cancel_flags = 0;
dp = NULL;
goto error_return;
}
xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
XFS_BMAP_INIT(&free_list, &first_block);
ASSERT(ip == NULL);
/*
* Reserve disk quota and the inode.
*/
error = XFS_TRANS_RESERVE_QUOTA(mp, tp, udqp, gdqp, resblks, 1, 0);
if (error)
goto error_return;
if (resblks == 0 && (error = xfs_dir_canenter(tp, dp, name, namelen)))
goto error_return;
rdev = (vap->va_mask & XFS_AT_RDEV) ? vap->va_rdev : 0;
error = xfs_dir_ialloc(&tp, dp, vap->va_mode, 1,
rdev, credp, prid, resblks > 0,
&ip, &committed);
if (error) {
if (error == ENOSPC)
goto error_return;
goto abort_return;
}
ITRACE(ip);
/*
* At this point, we've gotten a newly allocated inode.
* It is locked (and joined to the transaction).
*/
ASSERT(ismrlocked (&ip->i_lock, MR_UPDATE));
/*
* Now we join the directory inode to the transaction.
* We do not do it earlier because xfs_dir_ialloc
* might commit the previous transaction (and release
* all the locks).
*/
VN_HOLD(dir_vp);
xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
dp_joined_to_trans = B_TRUE;
error = xfs_dir_createname(tp, dp, name, namelen, ip->i_ino,
&first_block, &free_list, resblks ?
resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
if (error) {
ASSERT(error != ENOSPC);
goto abort_return;
}
xfs_ichgtime(dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
/*
* If this is a synchronous mount, make sure that the
* create transaction goes to disk before returning to
* the user.
*/
if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
xfs_trans_set_sync(tp);
}
dp->i_gen++;
/*
* Attach the dquot(s) to the inodes and modify them incore.
* These ids of the inode couldn't have changed since the new
* inode has been locked ever since it was created.
*/
XFS_QM_DQVOPCREATE(mp, tp, ip, udqp, gdqp);
/*
* xfs_trans_commit normally decrements the vnode ref count
* when it unlocks the inode. Since we want to return the
* vnode to the caller, we bump the vnode ref count now.
*/
IHOLD(ip);
vp = XFS_ITOV(ip);
error = xfs_bmap_finish(&tp, &free_list, &committed);
if (error) {
xfs_bmap_cancel(&free_list);
goto abort_rele;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
if (error) {
IRELE(ip);
tp = NULL;
goto error_return;
}
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
/*
* Propagate the fact that the vnode changed after the
* xfs_inode locks have been released.
*/
bhv_vop_vnode_change(vp, VCHANGE_FLAGS_TRUNCATED, 3);
*vpp = vp;
/* Fallthrough to std_return with error = 0 */
std_return:
if ( (*vpp || (error != 0 && dm_event_sent != 0)) &&
DM_EVENT_ENABLED(dir_vp->v_vfsp, XFS_BHVTOI(dir_bdp),
DM_EVENT_POSTCREATE)) {
(void) XFS_SEND_NAMESP(mp, DM_EVENT_POSTCREATE,
dir_vp, DM_RIGHT_NULL,
*vpp ? vp:NULL,
DM_RIGHT_NULL, name, NULL,
dm_di_mode, error, 0);
}
return error;
abort_return:
cancel_flags |= XFS_TRANS_ABORT;
/* FALLTHROUGH */
error_return:
if (tp != NULL)
xfs_trans_cancel(tp, cancel_flags);
if (!dp_joined_to_trans && (dp != NULL))
xfs_iunlock(dp, XFS_ILOCK_EXCL);
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
goto std_return;
abort_rele:
/*
* Wait until after the current transaction is aborted to
* release the inode. This prevents recursive transactions
* and deadlocks from xfs_inactive.
*/
cancel_flags |= XFS_TRANS_ABORT;
xfs_trans_cancel(tp, cancel_flags);
IRELE(ip);
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
goto std_return;
}
#ifdef DEBUG
/*
* Some counters to see if (and how often) we are hitting some deadlock
* prevention code paths.
*/
int xfs_rm_locks;
int xfs_rm_lock_delays;
int xfs_rm_attempts;
#endif
/*
* The following routine will lock the inodes associated with the
* directory and the named entry in the directory. The locks are
* acquired in increasing inode number.
*
* If the entry is "..", then only the directory is locked. The
* vnode ref count will still include that from the .. entry in
* this case.
*
* There is a deadlock we need to worry about. If the locked directory is
* in the AIL, it might be blocking up the log. The next inode we lock
* could be already locked by another thread waiting for log space (e.g
* a permanent log reservation with a long running transaction (see
* xfs_itruncate_finish)). To solve this, we must check if the directory
* is in the ail and use lock_nowait. If we can't lock, we need to
* drop the inode lock on the directory and try again. xfs_iunlock will
* potentially push the tail if we were holding up the log.
*/
STATIC int
xfs_lock_dir_and_entry(
xfs_inode_t *dp,
xfs_inode_t *ip) /* inode of entry 'name' */
{
int attempts;
xfs_ino_t e_inum;
xfs_inode_t *ips[2];
xfs_log_item_t *lp;
#ifdef DEBUG
xfs_rm_locks++;
#endif
attempts = 0;
again:
xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
e_inum = ip->i_ino;
ITRACE(ip);
/*
* We want to lock in increasing inum. Since we've already
* acquired the lock on the directory, we may need to release
* if if the inum of the entry turns out to be less.
*/
if (e_inum > dp->i_ino) {
/*
* We are already in the right order, so just
* lock on the inode of the entry.
* We need to use nowait if dp is in the AIL.
*/
lp = (xfs_log_item_t *)dp->i_itemp;
if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
attempts++;
#ifdef DEBUG
xfs_rm_attempts++;
#endif
/*
* Unlock dp and try again.
* xfs_iunlock will try to push the tail
* if the inode is in the AIL.
*/
xfs_iunlock(dp, XFS_ILOCK_EXCL);
if ((attempts % 5) == 0) {
delay(1); /* Don't just spin the CPU */
#ifdef DEBUG
xfs_rm_lock_delays++;
#endif
}
goto again;
}
} else {
xfs_ilock(ip, XFS_ILOCK_EXCL);
}
} else if (e_inum < dp->i_ino) {
xfs_iunlock(dp, XFS_ILOCK_EXCL);
ips[0] = ip;
ips[1] = dp;
xfs_lock_inodes(ips, 2, 0, XFS_ILOCK_EXCL);
}
/* else e_inum == dp->i_ino */
/* This can happen if we're asked to lock /x/..
* the entry is "..", which is also the parent directory.
*/
return 0;
}
#ifdef DEBUG
int xfs_locked_n;
int xfs_small_retries;
int xfs_middle_retries;
int xfs_lots_retries;
int xfs_lock_delays;
#endif
/*
* Bump the subclass so xfs_lock_inodes() acquires each lock with
* a different value
*/
static inline int
xfs_lock_inumorder(int lock_mode, int subclass)
{
if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
lock_mode |= (subclass + XFS_IOLOCK_INUMORDER) << XFS_IOLOCK_SHIFT;
if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))
lock_mode |= (subclass + XFS_ILOCK_INUMORDER) << XFS_ILOCK_SHIFT;
return lock_mode;
}
/*
* The following routine will lock n inodes in exclusive mode.
* We assume the caller calls us with the inodes in i_ino order.
*
* We need to detect deadlock where an inode that we lock
* is in the AIL and we start waiting for another inode that is locked
* by a thread in a long running transaction (such as truncate). This can
* result in deadlock since the long running trans might need to wait
* for the inode we just locked in order to push the tail and free space
* in the log.
*/
void
xfs_lock_inodes(
xfs_inode_t **ips,
int inodes,
int first_locked,
uint lock_mode)
{
int attempts = 0, i, j, try_lock;
xfs_log_item_t *lp;
ASSERT(ips && (inodes >= 2)); /* we need at least two */
if (first_locked) {
try_lock = 1;
i = 1;
} else {
try_lock = 0;
i = 0;
}
again:
for (; i < inodes; i++) {
ASSERT(ips[i]);
if (i && (ips[i] == ips[i-1])) /* Already locked */
continue;
/*
* If try_lock is not set yet, make sure all locked inodes
* are not in the AIL.
* If any are, set try_lock to be used later.
*/
if (!try_lock) {
for (j = (i - 1); j >= 0 && !try_lock; j--) {
lp = (xfs_log_item_t *)ips[j]->i_itemp;
if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
try_lock++;
}
}
}
/*
* If any of the previous locks we have locked is in the AIL,
* we must TRY to get the second and subsequent locks. If
* we can't get any, we must release all we have
* and try again.
*/
if (try_lock) {
/* try_lock must be 0 if i is 0. */
/*
* try_lock means we have an inode locked
* that is in the AIL.
*/
ASSERT(i != 0);
if (!xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) {
attempts++;
/*
* Unlock all previous guys and try again.
* xfs_iunlock will try to push the tail
* if the inode is in the AIL.
*/
for(j = i - 1; j >= 0; j--) {
/*
* Check to see if we've already
* unlocked this one.
* Not the first one going back,
* and the inode ptr is the same.
*/
if ((j != (i - 1)) && ips[j] ==
ips[j+1])
continue;
xfs_iunlock(ips[j], lock_mode);
}
if ((attempts % 5) == 0) {
delay(1); /* Don't just spin the CPU */
#ifdef DEBUG
xfs_lock_delays++;
#endif
}
i = 0;
try_lock = 0;
goto again;
}
} else {
xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
}
}
#ifdef DEBUG
if (attempts) {
if (attempts < 5) xfs_small_retries++;
else if (attempts < 100) xfs_middle_retries++;
else xfs_lots_retries++;
} else {
xfs_locked_n++;
}
#endif
}
#ifdef DEBUG
#define REMOVE_DEBUG_TRACE(x) {remove_which_error_return = (x);}
int remove_which_error_return = 0;
#else /* ! DEBUG */
#define REMOVE_DEBUG_TRACE(x)
#endif /* ! DEBUG */
/*
* xfs_remove
*
*/
STATIC int
xfs_remove(
bhv_desc_t *dir_bdp,
bhv_vname_t *dentry,
cred_t *credp)
{
bhv_vnode_t *dir_vp;
char *name = VNAME(dentry);
xfs_inode_t *dp, *ip;
xfs_trans_t *tp = NULL;
xfs_mount_t *mp;
int error = 0;
xfs_bmap_free_t free_list;
xfs_fsblock_t first_block;
int cancel_flags;
int committed;
int dm_di_mode = 0;
int link_zero;
uint resblks;
int namelen;
dir_vp = BHV_TO_VNODE(dir_bdp);
vn_trace_entry(dir_vp, __FUNCTION__, (inst_t *)__return_address);
dp = XFS_BHVTOI(dir_bdp);
mp = dp->i_mount;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
namelen = VNAMELEN(dentry);
if (!xfs_get_dir_entry(dentry, &ip)) {
dm_di_mode = ip->i_d.di_mode;
IRELE(ip);
}
if (DM_EVENT_ENABLED(dir_vp->v_vfsp, dp, DM_EVENT_REMOVE)) {
error = XFS_SEND_NAMESP(mp, DM_EVENT_REMOVE, dir_vp,
DM_RIGHT_NULL, NULL, DM_RIGHT_NULL,
name, NULL, dm_di_mode, 0, 0);
if (error)
return error;
}
/* From this point on, return through std_return */
ip = NULL;
/*
* We need to get a reference to ip before we get our log
* reservation. The reason for this is that we cannot call
* xfs_iget for an inode for which we do not have a reference
* once we've acquired a log reservation. This is because the
* inode we are trying to get might be in xfs_inactive going
* for a log reservation. Since we'll have to wait for the
* inactive code to complete before returning from xfs_iget,
* we need to make sure that we don't have log space reserved
* when we call xfs_iget. Instead we get an unlocked reference
* to the inode before getting our log reservation.
*/
error = xfs_get_dir_entry(dentry, &ip);
if (error) {
REMOVE_DEBUG_TRACE(__LINE__);
goto std_return;
}
dm_di_mode = ip->i_d.di_mode;
vn_trace_entry(XFS_ITOV(ip), __FUNCTION__, (inst_t *)__return_address);
ITRACE(ip);
error = XFS_QM_DQATTACH(mp, dp, 0);
if (!error && dp != ip)
error = XFS_QM_DQATTACH(mp, ip, 0);
if (error) {
REMOVE_DEBUG_TRACE(__LINE__);
IRELE(ip);
goto std_return;
}
tp = xfs_trans_alloc(mp, XFS_TRANS_REMOVE);
cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
/*
* We try to get the real space reservation first,
* allowing for directory btree deletion(s) implying
* possible bmap insert(s). If we can't get the space
* reservation then we use 0 instead, and avoid the bmap
* btree insert(s) in the directory code by, if the bmap
* insert tries to happen, instead trimming the LAST
* block from the directory.
*/
resblks = XFS_REMOVE_SPACE_RES(mp);
error = xfs_trans_reserve(tp, resblks, XFS_REMOVE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_REMOVE_LOG_COUNT);
if (error == ENOSPC) {
resblks = 0;
error = xfs_trans_reserve(tp, 0, XFS_REMOVE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_REMOVE_LOG_COUNT);
}
if (error) {
ASSERT(error != ENOSPC);
REMOVE_DEBUG_TRACE(__LINE__);
xfs_trans_cancel(tp, 0);
IRELE(ip);
return error;
}
error = xfs_lock_dir_and_entry(dp, ip);
if (error) {
REMOVE_DEBUG_TRACE(__LINE__);
xfs_trans_cancel(tp, cancel_flags);
IRELE(ip);
goto std_return;
}
/*
* At this point, we've gotten both the directory and the entry
* inodes locked.
*/
xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
if (dp != ip) {
/*
* Increment vnode ref count only in this case since
* there's an extra vnode reference in the case where
* dp == ip.
*/
IHOLD(dp);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
}
/*
* Entry must exist since we did a lookup in xfs_lock_dir_and_entry.
*/
XFS_BMAP_INIT(&free_list, &first_block);
error = xfs_dir_removename(tp, dp, name, namelen, ip->i_ino,
&first_block, &free_list, 0);
if (error) {
ASSERT(error != ENOENT);
REMOVE_DEBUG_TRACE(__LINE__);
goto error1;
}
xfs_ichgtime(dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
dp->i_gen++;
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
error = xfs_droplink(tp, ip);
if (error) {
REMOVE_DEBUG_TRACE(__LINE__);
goto error1;
}
/* Determine if this is the last link while
* we are in the transaction.
*/
link_zero = (ip)->i_d.di_nlink==0;
/*
* Take an extra ref on the inode so that it doesn't
* go to xfs_inactive() from within the commit.
*/
IHOLD(ip);
/*
* If this is a synchronous mount, make sure that the
* remove transaction goes to disk before returning to
* the user.
*/
if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
xfs_trans_set_sync(tp);
}
error = xfs_bmap_finish(&tp, &free_list, &committed);
if (error) {
REMOVE_DEBUG_TRACE(__LINE__);
goto error_rele;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
if (error) {
IRELE(ip);
goto std_return;
}
/*
* Before we drop our extra reference to the inode, purge it
* from the refcache if it is there. By waiting until afterwards
* to do the IRELE, we ensure that we won't go inactive in the
* xfs_refcache_purge_ip routine (although that would be OK).
*/
xfs_refcache_purge_ip(ip);
vn_trace_exit(XFS_ITOV(ip), __FUNCTION__, (inst_t *)__return_address);
/*
* Let interposed file systems know about removed links.
*/
bhv_vop_link_removed(XFS_ITOV(ip), dir_vp, link_zero);
IRELE(ip);
/* Fall through to std_return with error = 0 */
std_return:
if (DM_EVENT_ENABLED(dir_vp->v_vfsp, dp,
DM_EVENT_POSTREMOVE)) {
(void) XFS_SEND_NAMESP(mp, DM_EVENT_POSTREMOVE,
dir_vp, DM_RIGHT_NULL,
NULL, DM_RIGHT_NULL,
name, NULL, dm_di_mode, error, 0);
}
return error;
error1:
xfs_bmap_cancel(&free_list);
cancel_flags |= XFS_TRANS_ABORT;
xfs_trans_cancel(tp, cancel_flags);
goto std_return;
error_rele:
/*
* In this case make sure to not release the inode until after
* the current transaction is aborted. Releasing it beforehand
* can cause us to go to xfs_inactive and start a recursive
* transaction which can easily deadlock with the current one.
*/
xfs_bmap_cancel(&free_list);
cancel_flags |= XFS_TRANS_ABORT;
xfs_trans_cancel(tp, cancel_flags);
/*
* Before we drop our extra reference to the inode, purge it
* from the refcache if it is there. By waiting until afterwards
* to do the IRELE, we ensure that we won't go inactive in the
* xfs_refcache_purge_ip routine (although that would be OK).
*/
xfs_refcache_purge_ip(ip);
IRELE(ip);
goto std_return;
}
/*
* xfs_link
*
*/
STATIC int
xfs_link(
bhv_desc_t *target_dir_bdp,
bhv_vnode_t *src_vp,
bhv_vname_t *dentry,
cred_t *credp)
{
xfs_inode_t *tdp, *sip;
xfs_trans_t *tp;
xfs_mount_t *mp;
xfs_inode_t *ips[2];
int error;
xfs_bmap_free_t free_list;
xfs_fsblock_t first_block;
int cancel_flags;
int committed;
bhv_vnode_t *target_dir_vp;
int resblks;
char *target_name = VNAME(dentry);
int target_namelen;
target_dir_vp = BHV_TO_VNODE(target_dir_bdp);
vn_trace_entry(target_dir_vp, __FUNCTION__, (inst_t *)__return_address);
vn_trace_entry(src_vp, __FUNCTION__, (inst_t *)__return_address);
target_namelen = VNAMELEN(dentry);
ASSERT(!VN_ISDIR(src_vp));
sip = xfs_vtoi(src_vp);
tdp = XFS_BHVTOI(target_dir_bdp);
mp = tdp->i_mount;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
if (DM_EVENT_ENABLED(src_vp->v_vfsp, tdp, DM_EVENT_LINK)) {
error = XFS_SEND_NAMESP(mp, DM_EVENT_LINK,
target_dir_vp, DM_RIGHT_NULL,
src_vp, DM_RIGHT_NULL,
target_name, NULL, 0, 0, 0);
if (error)
return error;
}
/* Return through std_return after this point. */
error = XFS_QM_DQATTACH(mp, sip, 0);
if (!error && sip != tdp)
error = XFS_QM_DQATTACH(mp, tdp, 0);
if (error)
goto std_return;
tp = xfs_trans_alloc(mp, XFS_TRANS_LINK);
cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
resblks = XFS_LINK_SPACE_RES(mp, target_namelen);
error = xfs_trans_reserve(tp, resblks, XFS_LINK_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_LINK_LOG_COUNT);
if (error == ENOSPC) {
resblks = 0;
error = xfs_trans_reserve(tp, 0, XFS_LINK_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_LINK_LOG_COUNT);
}
if (error) {
cancel_flags = 0;
goto error_return;
}
if (sip->i_ino < tdp->i_ino) {
ips[0] = sip;
ips[1] = tdp;
} else {
ips[0] = tdp;
ips[1] = sip;
}
xfs_lock_inodes(ips, 2, 0, XFS_ILOCK_EXCL);
/*
* Increment vnode ref counts since xfs_trans_commit &
* xfs_trans_cancel will both unlock the inodes and
* decrement the associated ref counts.
*/
VN_HOLD(src_vp);
VN_HOLD(target_dir_vp);
xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
/*
* If the source has too many links, we can't make any more to it.
*/
if (sip->i_d.di_nlink >= XFS_MAXLINK) {
error = XFS_ERROR(EMLINK);
goto error_return;
}
/*
* If we are using project inheritance, we only allow hard link
* creation in our tree when the project IDs are the same; else
* the tree quota mechanism could be circumvented.
*/
if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
(tdp->i_d.di_projid != sip->i_d.di_projid))) {
error = XFS_ERROR(EXDEV);
goto error_return;
}
if (resblks == 0 &&
(error = xfs_dir_canenter(tp, tdp, target_name, target_namelen)))
goto error_return;
XFS_BMAP_INIT(&free_list, &first_block);
error = xfs_dir_createname(tp, tdp, target_name, target_namelen,
sip->i_ino, &first_block, &free_list,
resblks);
if (error)
goto abort_return;
xfs_ichgtime(tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
tdp->i_gen++;
xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
error = xfs_bumplink(tp, sip);
if (error)
goto abort_return;
/*
* If this is a synchronous mount, make sure that the
* link transaction goes to disk before returning to
* the user.
*/
if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
xfs_trans_set_sync(tp);
}
error = xfs_bmap_finish (&tp, &free_list, &committed);
if (error) {
xfs_bmap_cancel(&free_list);
goto abort_return;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
if (error)
goto std_return;
/* Fall through to std_return with error = 0. */
std_return:
if (DM_EVENT_ENABLED(src_vp->v_vfsp, sip,
DM_EVENT_POSTLINK)) {
(void) XFS_SEND_NAMESP(mp, DM_EVENT_POSTLINK,
target_dir_vp, DM_RIGHT_NULL,
src_vp, DM_RIGHT_NULL,
target_name, NULL, 0, error, 0);
}
return error;
abort_return:
cancel_flags |= XFS_TRANS_ABORT;
/* FALLTHROUGH */
error_return:
xfs_trans_cancel(tp, cancel_flags);
goto std_return;
}
/*
* xfs_mkdir
*
*/
STATIC int
xfs_mkdir(
bhv_desc_t *dir_bdp,
bhv_vname_t *dentry,
bhv_vattr_t *vap,
bhv_vnode_t **vpp,
cred_t *credp)
{
char *dir_name = VNAME(dentry);
xfs_inode_t *dp;
xfs_inode_t *cdp; /* inode of created dir */
bhv_vnode_t *cvp; /* vnode of created dir */
xfs_trans_t *tp;
xfs_mount_t *mp;
int cancel_flags;
int error;
int committed;
xfs_bmap_free_t free_list;
xfs_fsblock_t first_block;
bhv_vnode_t *dir_vp;
boolean_t dp_joined_to_trans;
boolean_t created = B_FALSE;
int dm_event_sent = 0;
xfs_prid_t prid;
struct xfs_dquot *udqp, *gdqp;
uint resblks;
int dm_di_mode;
int dir_namelen;
dir_vp = BHV_TO_VNODE(dir_bdp);
dp = XFS_BHVTOI(dir_bdp);
mp = dp->i_mount;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
dir_namelen = VNAMELEN(dentry);
tp = NULL;
dp_joined_to_trans = B_FALSE;
dm_di_mode = vap->va_mode;
if (DM_EVENT_ENABLED(dir_vp->v_vfsp, dp, DM_EVENT_CREATE)) {
error = XFS_SEND_NAMESP(mp, DM_EVENT_CREATE,
dir_vp, DM_RIGHT_NULL, NULL,
DM_RIGHT_NULL, dir_name, NULL,
dm_di_mode, 0, 0);
if (error)
return error;
dm_event_sent = 1;
}
/* Return through std_return after this point. */
vn_trace_entry(dir_vp, __FUNCTION__, (inst_t *)__return_address);
mp = dp->i_mount;
udqp = gdqp = NULL;
if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
prid = dp->i_d.di_projid;
else if (vap->va_mask & XFS_AT_PROJID)
prid = (xfs_prid_t)vap->va_projid;
else
prid = (xfs_prid_t)dfltprid;
/*
* Make sure that we have allocated dquot(s) on disk.
*/
error = XFS_QM_DQVOPALLOC(mp, dp,
current_fsuid(credp), current_fsgid(credp), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp);
if (error)
goto std_return;
tp = xfs_trans_alloc(mp, XFS_TRANS_MKDIR);
cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
resblks = XFS_MKDIR_SPACE_RES(mp, dir_namelen);
error = xfs_trans_reserve(tp, resblks, XFS_MKDIR_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_MKDIR_LOG_COUNT);
if (error == ENOSPC) {
resblks = 0;
error = xfs_trans_reserve(tp, 0, XFS_MKDIR_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES,
XFS_MKDIR_LOG_COUNT);
}
if (error) {
cancel_flags = 0;
dp = NULL;
goto error_return;
}
xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
/*
* Check for directory link count overflow.
*/
if (dp->i_d.di_nlink >= XFS_MAXLINK) {
error = XFS_ERROR(EMLINK);
goto error_return;
}
/*
* Reserve disk quota and the inode.
*/
error = XFS_TRANS_RESERVE_QUOTA(mp, tp, udqp, gdqp, resblks, 1, 0);
if (error)
goto error_return;
if (resblks == 0 &&
(error = xfs_dir_canenter(tp, dp, dir_name, dir_namelen)))
goto error_return;
/*
* create the directory inode.
*/
error = xfs_dir_ialloc(&tp, dp, vap->va_mode, 2,
0, credp, prid, resblks > 0,
&cdp, NULL);
if (error) {
if (error == ENOSPC)
goto error_return;
goto abort_return;
}
ITRACE(cdp);
/*
* Now we add the directory inode to the transaction.
* We waited until now since xfs_dir_ialloc might start
* a new transaction. Had we joined the transaction
* earlier, the locks might have gotten released.
*/
VN_HOLD(dir_vp);
xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
dp_joined_to_trans = B_TRUE;
XFS_BMAP_INIT(&free_list, &first_block);
error = xfs_dir_createname(tp, dp, dir_name, dir_namelen, cdp->i_ino,
&first_block, &free_list, resblks ?
resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
if (error) {
ASSERT(error != ENOSPC);
goto error1;
}
xfs_ichgtime(dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
/*
* Bump the in memory version number of the parent directory
* so that other processes accessing it will recognize that
* the directory has changed.
*/
dp->i_gen++;
error = xfs_dir_init(tp, cdp, dp);
if (error)
goto error2;
cdp->i_gen = 1;
error = xfs_bumplink(tp, dp);
if (error)
goto error2;
cvp = XFS_ITOV(cdp);
created = B_TRUE;
*vpp = cvp;
IHOLD(cdp);
/*
* Attach the dquots to the new inode and modify the icount incore.
*/
XFS_QM_DQVOPCREATE(mp, tp, cdp, udqp, gdqp);
/*
* If this is a synchronous mount, make sure that the
* mkdir transaction goes to disk before returning to
* the user.
*/
if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
xfs_trans_set_sync(tp);
}
error = xfs_bmap_finish(&tp, &free_list, &committed);
if (error) {
IRELE(cdp);
goto error2;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
if (error) {
IRELE(cdp);
}
/* Fall through to std_return with error = 0 or errno from
* xfs_trans_commit. */
std_return:
if ( (created || (error != 0 && dm_event_sent != 0)) &&
DM_EVENT_ENABLED(dir_vp->v_vfsp, XFS_BHVTOI(dir_bdp),
DM_EVENT_POSTCREATE)) {
(void) XFS_SEND_NAMESP(mp, DM_EVENT_POSTCREATE,
dir_vp, DM_RIGHT_NULL,
created ? XFS_ITOV(cdp):NULL,
DM_RIGHT_NULL,
dir_name, NULL,
dm_di_mode, error, 0);
}
return error;
error2:
error1:
xfs_bmap_cancel(&free_list);
abort_return:
cancel_flags |= XFS_TRANS_ABORT;
error_return:
xfs_trans_cancel(tp, cancel_flags);
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
if (!dp_joined_to_trans && (dp != NULL)) {
xfs_iunlock(dp, XFS_ILOCK_EXCL);
}
goto std_return;
}
/*
* xfs_rmdir
*
*/
STATIC int
xfs_rmdir(
bhv_desc_t *dir_bdp,
bhv_vname_t *dentry,
cred_t *credp)
{
char *name = VNAME(dentry);
xfs_inode_t *dp;
xfs_inode_t *cdp; /* child directory */
xfs_trans_t *tp;
xfs_mount_t *mp;
int error;
xfs_bmap_free_t free_list;
xfs_fsblock_t first_block;
int cancel_flags;
int committed;
bhv_vnode_t *dir_vp;
int dm_di_mode = S_IFDIR;
int last_cdp_link;
int namelen;
uint resblks;
dir_vp = BHV_TO_VNODE(dir_bdp);
dp = XFS_BHVTOI(dir_bdp);
mp = dp->i_mount;
vn_trace_entry(dir_vp, __FUNCTION__, (inst_t *)__return_address);
if (XFS_FORCED_SHUTDOWN(XFS_BHVTOI(dir_bdp)->i_mount))
return XFS_ERROR(EIO);
namelen = VNAMELEN(dentry);
if (!xfs_get_dir_entry(dentry, &cdp)) {
dm_di_mode = cdp->i_d.di_mode;
IRELE(cdp);
}
if (DM_EVENT_ENABLED(dir_vp->v_vfsp, dp, DM_EVENT_REMOVE)) {
error = XFS_SEND_NAMESP(mp, DM_EVENT_REMOVE,
dir_vp, DM_RIGHT_NULL,
NULL, DM_RIGHT_NULL,
name, NULL, dm_di_mode, 0, 0);
if (error)
return XFS_ERROR(error);
}
/* Return through std_return after this point. */
cdp = NULL;
/*
* We need to get a reference to cdp before we get our log
* reservation. The reason for this is that we cannot call
* xfs_iget for an inode for which we do not have a reference
* once we've acquired a log reservation. This is because the
* inode we are trying to get might be in xfs_inactive going
* for a log reservation. Since we'll have to wait for the
* inactive code to complete before returning from xfs_iget,
* we need to make sure that we don't have log space reserved
* when we call xfs_iget. Instead we get an unlocked reference
* to the inode before getting our log reservation.
*/
error = xfs_get_dir_entry(dentry, &cdp);
if (error) {
REMOVE_DEBUG_TRACE(__LINE__);
goto std_return;
}
mp = dp->i_mount;
dm_di_mode = cdp->i_d.di_mode;
/*
* Get the dquots for the inodes.
*/
error = XFS_QM_DQATTACH(mp, dp, 0);
if (!error && dp != cdp)
error = XFS_QM_DQATTACH(mp, cdp, 0);
if (error) {
IRELE(cdp);
REMOVE_DEBUG_TRACE(__LINE__);
goto std_return;
}
tp = xfs_trans_alloc(mp, XFS_TRANS_RMDIR);
cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
/*
* We try to get the real space reservation first,
* allowing for directory btree deletion(s) implying
* possible bmap insert(s). If we can't get the space
* reservation then we use 0 instead, and avoid the bmap
* btree insert(s) in the directory code by, if the bmap
* insert tries to happen, instead trimming the LAST
* block from the directory.
*/
resblks = XFS_REMOVE_SPACE_RES(mp);
error = xfs_trans_reserve(tp, resblks, XFS_REMOVE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_DEFAULT_LOG_COUNT);
if (error == ENOSPC) {
resblks = 0;
error = xfs_trans_reserve(tp, 0, XFS_REMOVE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_DEFAULT_LOG_COUNT);
}
if (error) {
ASSERT(error != ENOSPC);
cancel_flags = 0;
IRELE(cdp);
goto error_return;
}
XFS_BMAP_INIT(&free_list, &first_block);
/*
* Now lock the child directory inode and the parent directory
* inode in the proper order. This will take care of validating
* that the directory entry for the child directory inode has
* not changed while we were obtaining a log reservation.
*/
error = xfs_lock_dir_and_entry(dp, cdp);
if (error) {
xfs_trans_cancel(tp, cancel_flags);
IRELE(cdp);
goto std_return;
}
xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
if (dp != cdp) {
/*
* Only increment the parent directory vnode count if
* we didn't bump it in looking up cdp. The only time
* we don't bump it is when we're looking up ".".
*/
VN_HOLD(dir_vp);
}
ITRACE(cdp);
xfs_trans_ijoin(tp, cdp, XFS_ILOCK_EXCL);
ASSERT(cdp->i_d.di_nlink >= 2);
if (cdp->i_d.di_nlink != 2) {
error = XFS_ERROR(ENOTEMPTY);
goto error_return;
}
if (!xfs_dir_isempty(cdp)) {
error = XFS_ERROR(ENOTEMPTY);
goto error_return;
}
error = xfs_dir_removename(tp, dp, name, namelen, cdp->i_ino,
&first_block, &free_list, resblks);
if (error)
goto error1;
xfs_ichgtime(dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
/*
* Bump the in memory generation count on the parent
* directory so that other can know that it has changed.
*/
dp->i_gen++;
/*
* Drop the link from cdp's "..".
*/
error = xfs_droplink(tp, dp);
if (error) {
goto error1;
}
/*
* Drop the link from dp to cdp.
*/
error = xfs_droplink(tp, cdp);
if (error) {
goto error1;
}
/*
* Drop the "." link from cdp to self.
*/
error = xfs_droplink(tp, cdp);
if (error) {
goto error1;
}
/* Determine these before committing transaction */
last_cdp_link = (cdp)->i_d.di_nlink==0;
/*
* Take an extra ref on the child vnode so that it
* does not go to xfs_inactive() from within the commit.
*/
IHOLD(cdp);
/*
* If this is a synchronous mount, make sure that the
* rmdir transaction goes to disk before returning to
* the user.
*/
if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
xfs_trans_set_sync(tp);
}
error = xfs_bmap_finish (&tp, &free_list, &committed);
if (error) {
xfs_bmap_cancel(&free_list);
xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES |
XFS_TRANS_ABORT));
IRELE(cdp);
goto std_return;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
if (error) {
IRELE(cdp);
goto std_return;
}
/*
* Let interposed file systems know about removed links.
*/
bhv_vop_link_removed(XFS_ITOV(cdp), dir_vp, last_cdp_link);
IRELE(cdp);
/* Fall through to std_return with error = 0 or the errno
* from xfs_trans_commit. */
std_return:
if (DM_EVENT_ENABLED(dir_vp->v_vfsp, dp, DM_EVENT_POSTREMOVE)) {
(void) XFS_SEND_NAMESP(mp, DM_EVENT_POSTREMOVE,
dir_vp, DM_RIGHT_NULL,
NULL, DM_RIGHT_NULL,
name, NULL, dm_di_mode,
error, 0);
}
return error;
error1:
xfs_bmap_cancel(&free_list);
cancel_flags |= XFS_TRANS_ABORT;
/* FALLTHROUGH */
error_return:
xfs_trans_cancel(tp, cancel_flags);
goto std_return;
}
/*
* Read dp's entries starting at uiop->uio_offset and translate them into
* bufsize bytes worth of struct dirents starting at bufbase.
*/
STATIC int
xfs_readdir(
bhv_desc_t *dir_bdp,
uio_t *uiop,
cred_t *credp,
int *eofp)
{
xfs_inode_t *dp;
xfs_trans_t *tp = NULL;
int error = 0;
uint lock_mode;
vn_trace_entry(BHV_TO_VNODE(dir_bdp), __FUNCTION__,
(inst_t *)__return_address);
dp = XFS_BHVTOI(dir_bdp);
if (XFS_FORCED_SHUTDOWN(dp->i_mount))
return XFS_ERROR(EIO);
lock_mode = xfs_ilock_map_shared(dp);
error = xfs_dir_getdents(tp, dp, uiop, eofp);
xfs_iunlock_map_shared(dp, lock_mode);
return error;
}
STATIC int
xfs_symlink(
bhv_desc_t *dir_bdp,
bhv_vname_t *dentry,
bhv_vattr_t *vap,
char *target_path,
bhv_vnode_t **vpp,
cred_t *credp)
{
xfs_trans_t *tp;
xfs_mount_t *mp;
xfs_inode_t *dp;
xfs_inode_t *ip;
int error;
int pathlen;
xfs_bmap_free_t free_list;
xfs_fsblock_t first_block;
boolean_t dp_joined_to_trans;
bhv_vnode_t *dir_vp;
uint cancel_flags;
int committed;
xfs_fileoff_t first_fsb;
xfs_filblks_t fs_blocks;
int nmaps;
xfs_bmbt_irec_t mval[SYMLINK_MAPS];
xfs_daddr_t d;
char *cur_chunk;
int byte_cnt;
int n;
xfs_buf_t *bp;
xfs_prid_t prid;
struct xfs_dquot *udqp, *gdqp;
uint resblks;
char *link_name = VNAME(dentry);
int link_namelen;
*vpp = NULL;
dir_vp = BHV_TO_VNODE(dir_bdp);
dp = XFS_BHVTOI(dir_bdp);
dp_joined_to_trans = B_FALSE;
error = 0;
ip = NULL;
tp = NULL;
vn_trace_entry(dir_vp, __FUNCTION__, (inst_t *)__return_address);
mp = dp->i_mount;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
link_namelen = VNAMELEN(dentry);
/*
* Check component lengths of the target path name.
*/
pathlen = strlen(target_path);
if (pathlen >= MAXPATHLEN) /* total string too long */
return XFS_ERROR(ENAMETOOLONG);
if (pathlen >= MAXNAMELEN) { /* is any component too long? */
int len, total;
char *path;
for (total = 0, path = target_path; total < pathlen;) {
/*
* Skip any slashes.
*/
while(*path == '/') {
total++;
path++;
}
/*
* Count up to the next slash or end of path.
* Error out if the component is bigger than MAXNAMELEN.
*/
for(len = 0; *path != '/' && total < pathlen;total++, path++) {
if (++len >= MAXNAMELEN) {
error = ENAMETOOLONG;
return error;
}
}
}
}
if (DM_EVENT_ENABLED(dir_vp->v_vfsp, dp, DM_EVENT_SYMLINK)) {
error = XFS_SEND_NAMESP(mp, DM_EVENT_SYMLINK, dir_vp,
DM_RIGHT_NULL, NULL, DM_RIGHT_NULL,
link_name, target_path, 0, 0, 0);
if (error)
return error;
}
/* Return through std_return after this point. */
udqp = gdqp = NULL;
if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
prid = dp->i_d.di_projid;
else if (vap->va_mask & XFS_AT_PROJID)
prid = (xfs_prid_t)vap->va_projid;
else
prid = (xfs_prid_t)dfltprid;
/*
* Make sure that we have allocated dquot(s) on disk.
*/
error = XFS_QM_DQVOPALLOC(mp, dp,
current_fsuid(credp), current_fsgid(credp), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp);
if (error)
goto std_return;
tp = xfs_trans_alloc(mp, XFS_TRANS_SYMLINK);
cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
/*
* The symlink will fit into the inode data fork?
* There can't be any attributes so we get the whole variable part.
*/
if (pathlen <= XFS_LITINO(mp))
fs_blocks = 0;
else
fs_blocks = XFS_B_TO_FSB(mp, pathlen);
resblks = XFS_SYMLINK_SPACE_RES(mp, link_namelen, fs_blocks);
error = xfs_trans_reserve(tp, resblks, XFS_SYMLINK_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT);
if (error == ENOSPC && fs_blocks == 0) {
resblks = 0;
error = xfs_trans_reserve(tp, 0, XFS_SYMLINK_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT);
}
if (error) {
cancel_flags = 0;
dp = NULL;
goto error_return;
}
xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
/*
* Check whether the directory allows new symlinks or not.
*/
if (dp->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) {
error = XFS_ERROR(EPERM);
goto error_return;
}
/*
* Reserve disk quota : blocks and inode.
*/
error = XFS_TRANS_RESERVE_QUOTA(mp, tp, udqp, gdqp, resblks, 1, 0);
if (error)
goto error_return;
/*
* Check for ability to enter directory entry, if no space reserved.
*/
if (resblks == 0 &&
(error = xfs_dir_canenter(tp, dp, link_name, link_namelen)))
goto error_return;
/*
* Initialize the bmap freelist prior to calling either
* bmapi or the directory create code.
*/
XFS_BMAP_INIT(&free_list, &first_block);
/*
* Allocate an inode for the symlink.
*/
error = xfs_dir_ialloc(&tp, dp, S_IFLNK | (vap->va_mode&~S_IFMT),
1, 0, credp, prid, resblks > 0, &ip, NULL);
if (error) {
if (error == ENOSPC)
goto error_return;
goto error1;
}
ITRACE(ip);
VN_HOLD(dir_vp);
xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
dp_joined_to_trans = B_TRUE;
/*
* Also attach the dquot(s) to it, if applicable.
*/
XFS_QM_DQVOPCREATE(mp, tp, ip, udqp, gdqp);
if (resblks)
resblks -= XFS_IALLOC_SPACE_RES(mp);
/*
* If the symlink will fit into the inode, write it inline.
*/
if (pathlen <= XFS_IFORK_DSIZE(ip)) {
xfs_idata_realloc(ip, pathlen, XFS_DATA_FORK);
memcpy(ip->i_df.if_u1.if_data, target_path, pathlen);
ip->i_d.di_size = pathlen;
/*
* The inode was initially created in extent format.
*/
ip->i_df.if_flags &= ~(XFS_IFEXTENTS | XFS_IFBROOT);
ip->i_df.if_flags |= XFS_IFINLINE;
ip->i_d.di_format = XFS_DINODE_FMT_LOCAL;
xfs_trans_log_inode(tp, ip, XFS_ILOG_DDATA | XFS_ILOG_CORE);
} else {
first_fsb = 0;
nmaps = SYMLINK_MAPS;
error = xfs_bmapi(tp, ip, first_fsb, fs_blocks,
XFS_BMAPI_WRITE | XFS_BMAPI_METADATA,
&first_block, resblks, mval, &nmaps,
&free_list, NULL);
if (error) {
goto error1;
}
if (resblks)
resblks -= fs_blocks;
ip->i_d.di_size = pathlen;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
cur_chunk = target_path;
for (n = 0; n < nmaps; n++) {
d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
BTOBB(byte_cnt), 0);
ASSERT(bp && !XFS_BUF_GETERROR(bp));
if (pathlen < byte_cnt) {
byte_cnt = pathlen;
}
pathlen -= byte_cnt;
memcpy(XFS_BUF_PTR(bp), cur_chunk, byte_cnt);
cur_chunk += byte_cnt;
xfs_trans_log_buf(tp, bp, 0, byte_cnt - 1);
}
}
/*
* Create the directory entry for the symlink.
*/
error = xfs_dir_createname(tp, dp, link_name, link_namelen, ip->i_ino,
&first_block, &free_list, resblks);
if (error)
goto error1;
xfs_ichgtime(dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
/*
* Bump the in memory version number of the parent directory
* so that other processes accessing it will recognize that
* the directory has changed.
*/
dp->i_gen++;
/*
* If this is a synchronous mount, make sure that the
* symlink transaction goes to disk before returning to
* the user.
*/
if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
xfs_trans_set_sync(tp);
}
/*
* xfs_trans_commit normally decrements the vnode ref count
* when it unlocks the inode. Since we want to return the
* vnode to the caller, we bump the vnode ref count now.
*/
IHOLD(ip);
error = xfs_bmap_finish(&tp, &free_list, &committed);
if (error) {
goto error2;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
/* Fall through to std_return with error = 0 or errno from
* xfs_trans_commit */
std_return:
if (DM_EVENT_ENABLED(dir_vp->v_vfsp, XFS_BHVTOI(dir_bdp),
DM_EVENT_POSTSYMLINK)) {
(void) XFS_SEND_NAMESP(mp, DM_EVENT_POSTSYMLINK,
dir_vp, DM_RIGHT_NULL,
error ? NULL : XFS_ITOV(ip),
DM_RIGHT_NULL, link_name, target_path,
0, error, 0);
}
if (!error) {
bhv_vnode_t *vp;
ASSERT(ip);
vp = XFS_ITOV(ip);
*vpp = vp;
}
return error;
error2:
IRELE(ip);
error1:
xfs_bmap_cancel(&free_list);
cancel_flags |= XFS_TRANS_ABORT;
error_return:
xfs_trans_cancel(tp, cancel_flags);
XFS_QM_DQRELE(mp, udqp);
XFS_QM_DQRELE(mp, gdqp);
if (!dp_joined_to_trans && (dp != NULL)) {
xfs_iunlock(dp, XFS_ILOCK_EXCL);
}
goto std_return;
}
/*
* xfs_fid2
*
* A fid routine that takes a pointer to a previously allocated
* fid structure (like xfs_fast_fid) but uses a 64 bit inode number.
*/
STATIC int
xfs_fid2(
bhv_desc_t *bdp,
fid_t *fidp)
{
xfs_inode_t *ip;
xfs_fid2_t *xfid;
vn_trace_entry(BHV_TO_VNODE(bdp), __FUNCTION__,
(inst_t *)__return_address);
ASSERT(sizeof(fid_t) >= sizeof(xfs_fid2_t));
xfid = (xfs_fid2_t *)fidp;
ip = XFS_BHVTOI(bdp);
xfid->fid_len = sizeof(xfs_fid2_t) - sizeof(xfid->fid_len);
xfid->fid_pad = 0;
/*
* use memcpy because the inode is a long long and there's no
* assurance that xfid->fid_ino is properly aligned.
*/
memcpy(&xfid->fid_ino, &ip->i_ino, sizeof(xfid->fid_ino));
xfid->fid_gen = ip->i_d.di_gen;
return 0;
}
/*
* xfs_rwlock
*/
int
xfs_rwlock(
bhv_desc_t *bdp,
bhv_vrwlock_t locktype)
{
xfs_inode_t *ip;
bhv_vnode_t *vp;
vp = BHV_TO_VNODE(bdp);
if (VN_ISDIR(vp))
return 1;
ip = XFS_BHVTOI(bdp);
if (locktype == VRWLOCK_WRITE) {
xfs_ilock(ip, XFS_IOLOCK_EXCL);
} else if (locktype == VRWLOCK_TRY_READ) {
return xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED);
} else if (locktype == VRWLOCK_TRY_WRITE) {
return xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL);
} else {
ASSERT((locktype == VRWLOCK_READ) ||
(locktype == VRWLOCK_WRITE_DIRECT));
xfs_ilock(ip, XFS_IOLOCK_SHARED);
}
return 1;
}
/*
* xfs_rwunlock
*/
void
xfs_rwunlock(
bhv_desc_t *bdp,
bhv_vrwlock_t locktype)
{
xfs_inode_t *ip;
bhv_vnode_t *vp;
vp = BHV_TO_VNODE(bdp);
if (VN_ISDIR(vp))
return;
ip = XFS_BHVTOI(bdp);
if (locktype == VRWLOCK_WRITE) {
/*
* In the write case, we may have added a new entry to
* the reference cache. This might store a pointer to
* an inode to be released in this inode. If it is there,
* clear the pointer and release the inode after unlocking
* this one.
*/
xfs_refcache_iunlock(ip, XFS_IOLOCK_EXCL);
} else {
ASSERT((locktype == VRWLOCK_READ) ||
(locktype == VRWLOCK_WRITE_DIRECT));
xfs_iunlock(ip, XFS_IOLOCK_SHARED);
}
return;
}
STATIC int
xfs_inode_flush(
bhv_desc_t *bdp,
int flags)
{
xfs_inode_t *ip;
xfs_mount_t *mp;
xfs_inode_log_item_t *iip;
int error = 0;
ip = XFS_BHVTOI(bdp);
mp = ip->i_mount;
iip = ip->i_itemp;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
/*
* Bypass inodes which have already been cleaned by
* the inode flush clustering code inside xfs_iflush
*/
if ((ip->i_update_core == 0) &&
((iip == NULL) || !(iip->ili_format.ilf_fields & XFS_ILOG_ALL)))
return 0;
if (flags & FLUSH_LOG) {
if (iip && iip->ili_last_lsn) {
xlog_t *log = mp->m_log;
xfs_lsn_t sync_lsn;
int s, log_flags = XFS_LOG_FORCE;
s = GRANT_LOCK(log);
sync_lsn = log->l_last_sync_lsn;
GRANT_UNLOCK(log, s);
if ((XFS_LSN_CMP(iip->ili_last_lsn, sync_lsn) <= 0))
return 0;
if (flags & FLUSH_SYNC)
log_flags |= XFS_LOG_SYNC;
return xfs_log_force(mp, iip->ili_last_lsn, log_flags);
}
}
/*
* We make this non-blocking if the inode is contended,
* return EAGAIN to indicate to the caller that they
* did not succeed. This prevents the flush path from
* blocking on inodes inside another operation right
* now, they get caught later by xfs_sync.
*/
if (flags & FLUSH_INODE) {
int flush_flags;
if (xfs_ipincount(ip))
return EAGAIN;
if (flags & FLUSH_SYNC) {
xfs_ilock(ip, XFS_ILOCK_SHARED);
xfs_iflock(ip);
} else if (xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
if (xfs_ipincount(ip) || !xfs_iflock_nowait(ip)) {
xfs_iunlock(ip, XFS_ILOCK_SHARED);
return EAGAIN;
}
} else {
return EAGAIN;
}
if (flags & FLUSH_SYNC)
flush_flags = XFS_IFLUSH_SYNC;
else
flush_flags = XFS_IFLUSH_ASYNC;
error = xfs_iflush(ip, flush_flags);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
}
return error;
}
int
xfs_set_dmattrs (
bhv_desc_t *bdp,
u_int evmask,
u_int16_t state,
cred_t *credp)
{
xfs_inode_t *ip;
xfs_trans_t *tp;
xfs_mount_t *mp;
int error;
if (!capable(CAP_SYS_ADMIN))
return XFS_ERROR(EPERM);
ip = XFS_BHVTOI(bdp);
mp = ip->i_mount;
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
tp = xfs_trans_alloc(mp, XFS_TRANS_SET_DMATTRS);
error = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES (mp), 0, 0, 0);
if (error) {
xfs_trans_cancel(tp, 0);
return error;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
ip->i_iocore.io_dmevmask = ip->i_d.di_dmevmask = evmask;
ip->i_iocore.io_dmstate = ip->i_d.di_dmstate = state;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
IHOLD(ip);
error = xfs_trans_commit(tp, 0);
return error;
}
STATIC int
xfs_reclaim(
bhv_desc_t *bdp)
{
xfs_inode_t *ip;
bhv_vnode_t *vp;
vp = BHV_TO_VNODE(bdp);
ip = XFS_BHVTOI(bdp);
vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
ASSERT(!VN_MAPPED(vp));
/* bad inode, get out here ASAP */
if (VN_BAD(vp)) {
xfs_ireclaim(ip);
return 0;
}
vn_iowait(vp);
ASSERT(XFS_FORCED_SHUTDOWN(ip->i_mount) || ip->i_delayed_blks == 0);
/*
* Make sure the atime in the XFS inode is correct before freeing the
* Linux inode.
*/
xfs_synchronize_atime(ip);
/*
* If we have nothing to flush with this inode then complete the
* teardown now, otherwise break the link between the xfs inode and the
* linux inode and clean up the xfs inode later. This avoids flushing
* the inode to disk during the delete operation itself.
*
* When breaking the link, we need to set the XFS_IRECLAIMABLE flag
* first to ensure that xfs_iunpin() will never see an xfs inode
* that has a linux inode being reclaimed. Synchronisation is provided
* by the i_flags_lock.
*/
if (!ip->i_update_core && (ip->i_itemp == NULL)) {
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_iflock(ip);
return xfs_finish_reclaim(ip, 1, XFS_IFLUSH_DELWRI_ELSE_SYNC);
} else {
xfs_mount_t *mp = ip->i_mount;
/* Protect sync and unpin from us */
XFS_MOUNT_ILOCK(mp);
spin_lock(&ip->i_flags_lock);
__xfs_iflags_set(ip, XFS_IRECLAIMABLE);
vn_bhv_remove(VN_BHV_HEAD(vp), XFS_ITOBHV(ip));
spin_unlock(&ip->i_flags_lock);
list_add_tail(&ip->i_reclaim, &mp->m_del_inodes);
XFS_MOUNT_IUNLOCK(mp);
}
return 0;
}
int
xfs_finish_reclaim(
xfs_inode_t *ip,
int locked,
int sync_mode)
{
xfs_ihash_t *ih = ip->i_hash;
bhv_vnode_t *vp = XFS_ITOV_NULL(ip);
int error;
if (vp && VN_BAD(vp))
goto reclaim;
/* The hash lock here protects a thread in xfs_iget_core from
* racing with us on linking the inode back with a vnode.
* Once we have the XFS_IRECLAIM flag set it will not touch
* us.
*/
write_lock(&ih->ih_lock);
spin_lock(&ip->i_flags_lock);
if (__xfs_iflags_test(ip, XFS_IRECLAIM) ||
(!__xfs_iflags_test(ip, XFS_IRECLAIMABLE) && vp == NULL)) {
spin_unlock(&ip->i_flags_lock);
write_unlock(&ih->ih_lock);
if (locked) {
xfs_ifunlock(ip);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
}
return 1;
}
__xfs_iflags_set(ip, XFS_IRECLAIM);
spin_unlock(&ip->i_flags_lock);
write_unlock(&ih->ih_lock);
/*
* If the inode is still dirty, then flush it out. If the inode
* is not in the AIL, then it will be OK to flush it delwri as
* long as xfs_iflush() does not keep any references to the inode.
* We leave that decision up to xfs_iflush() since it has the
* knowledge of whether it's OK to simply do a delwri flush of
* the inode or whether we need to wait until the inode is
* pulled from the AIL.
* We get the flush lock regardless, though, just to make sure
* we don't free it while it is being flushed.
*/
if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
if (!locked) {
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_iflock(ip);
}
if (ip->i_update_core ||
((ip->i_itemp != NULL) &&
(ip->i_itemp->ili_format.ilf_fields != 0))) {
error = xfs_iflush(ip, sync_mode);
/*
* If we hit an error, typically because of filesystem
* shutdown, we don't need to let vn_reclaim to know
* because we're gonna reclaim the inode anyway.
*/
if (error) {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
goto reclaim;
}
xfs_iflock(ip); /* synchronize with xfs_iflush_done */
}
ASSERT(ip->i_update_core == 0);
ASSERT(ip->i_itemp == NULL ||
ip->i_itemp->ili_format.ilf_fields == 0);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
} else if (locked) {
/*
* We are not interested in doing an iflush if we're
* in the process of shutting down the filesystem forcibly.
* So, just reclaim the inode.
*/
xfs_ifunlock(ip);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
}
reclaim:
xfs_ireclaim(ip);
return 0;
}
int
xfs_finish_reclaim_all(xfs_mount_t *mp, int noblock)
{
int purged;
xfs_inode_t *ip, *n;
int done = 0;
while (!done) {
purged = 0;
XFS_MOUNT_ILOCK(mp);
list_for_each_entry_safe(ip, n, &mp->m_del_inodes, i_reclaim) {
if (noblock) {
if (xfs_ilock_nowait(ip, XFS_ILOCK_EXCL) == 0)
continue;
if (xfs_ipincount(ip) ||
!xfs_iflock_nowait(ip)) {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
continue;
}
}
XFS_MOUNT_IUNLOCK(mp);
if (xfs_finish_reclaim(ip, noblock,
XFS_IFLUSH_DELWRI_ELSE_ASYNC))
delay(1);
purged = 1;
break;
}
done = !purged;
}
XFS_MOUNT_IUNLOCK(mp);
return 0;
}
/*
* xfs_alloc_file_space()
* This routine allocates disk space for the given file.
*
* If alloc_type == 0, this request is for an ALLOCSP type
* request which will change the file size. In this case, no
* DMAPI event will be generated by the call. A TRUNCATE event
* will be generated later by xfs_setattr.
*
* If alloc_type != 0, this request is for a RESVSP type
* request, and a DMAPI DM_EVENT_WRITE will be generated if the
* lower block boundary byte address is less than the file's
* length.
*
* RETURNS:
* 0 on success
* errno on error
*
*/
STATIC int
xfs_alloc_file_space(
xfs_inode_t *ip,
xfs_off_t offset,
xfs_off_t len,
int alloc_type,
int attr_flags)
{
xfs_mount_t *mp = ip->i_mount;
xfs_off_t count;
xfs_filblks_t allocated_fsb;
xfs_filblks_t allocatesize_fsb;
xfs_extlen_t extsz, temp;
xfs_fileoff_t startoffset_fsb;
xfs_fsblock_t firstfsb;
int nimaps;
int bmapi_flag;
int quota_flag;
int rt;
xfs_trans_t *tp;
xfs_bmbt_irec_t imaps[1], *imapp;
xfs_bmap_free_t free_list;
uint qblocks, resblks, resrtextents;
int committed;
int error;
vn_trace_entry(XFS_ITOV(ip), __FUNCTION__, (inst_t *)__return_address);
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(EIO);
rt = XFS_IS_REALTIME_INODE(ip);
if (unlikely(rt)) {
if (!(extsz = ip->i_d.di_extsize))
extsz = mp->m_sb.sb_rextsize;
} else {
extsz = ip->i_d.di_extsize;
}
if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
return error;
if (len <= 0)
return XFS_ERROR(EINVAL);
count = len;
error = 0;
imapp = &imaps[0];
nimaps = 1;
bmapi_flag = XFS_BMAPI_WRITE | (alloc_type ? XFS_BMAPI_PREALLOC : 0);
startoffset_fsb = XFS_B_TO_FSBT(mp, offset);
allocatesize_fsb = XFS_B_TO_FSB(mp, count);
/* Generate a DMAPI event if needed. */
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
if (alloc_type != 0 && offset < ip->i_size &&
(attr_flags&ATTR_DMI) == 0 &&
DM_EVENT_ENABLED(XFS_MTOVFS(mp), ip, DM_EVENT_WRITE)) {
xfs_off_t end_dmi_offset;
end_dmi_offset = offset+len;
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
if (end_dmi_offset > ip->i_size)
end_dmi_offset = ip->i_size;
error = XFS_SEND_DATA(mp, DM_EVENT_WRITE, XFS_ITOV(ip),
offset, end_dmi_offset - offset,
0, NULL);
if (error)
return error;
}
/*
* Allocate file space until done or until there is an error
*/
retry:
while (allocatesize_fsb && !error) {
xfs_fileoff_t s, e;
/*
* Determine space reservations for data/realtime.
*/
if (unlikely(extsz)) {
s = startoffset_fsb;
do_div(s, extsz);
s *= extsz;
e = startoffset_fsb + allocatesize_fsb;
if ((temp = do_mod(startoffset_fsb, extsz)))
e += temp;
if ((temp = do_mod(e, extsz)))
e += extsz - temp;
} else {
s = 0;
e = allocatesize_fsb;
}
if (unlikely(rt)) {
resrtextents = qblocks = (uint)(e - s);
resrtextents /= mp->m_sb.sb_rextsize;
resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
quota_flag = XFS_QMOPT_RES_RTBLKS;
} else {
resrtextents = 0;
resblks = qblocks = \
XFS_DIOSTRAT_SPACE_RES(mp, (uint)(e - s));
quota_flag = XFS_QMOPT_RES_REGBLKS;
}
/*
* Allocate and setup the transaction.
*/
tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
error = xfs_trans_reserve(tp, resblks,
XFS_WRITE_LOG_RES(mp), resrtextents,
XFS_TRANS_PERM_LOG_RES,
XFS_WRITE_LOG_COUNT);
/*
* Check for running out of space
*/
if (error) {
/*
* Free the transaction structure.
*/
ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
xfs_trans_cancel(tp, 0);
break;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
error = XFS_TRANS_RESERVE_QUOTA_NBLKS(mp, tp, ip,
qblocks, 0, quota_flag);
if (error)
goto error1;
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
/*
* Issue the xfs_bmapi() call to allocate the blocks
*/
XFS_BMAP_INIT(&free_list, &firstfsb);
error = XFS_BMAPI(mp, tp, &ip->i_iocore, startoffset_fsb,
allocatesize_fsb, bmapi_flag,
&firstfsb, 0, imapp, &nimaps,
&free_list, NULL);
if (error) {
goto error0;
}
/*
* Complete the transaction
*/
error = xfs_bmap_finish(&tp, &free_list, &committed);
if (error) {
goto error0;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
if (error) {
break;
}
allocated_fsb = imapp->br_blockcount;
if (nimaps == 0) {
error = XFS_ERROR(ENOSPC);
break;
}
startoffset_fsb += allocated_fsb;
allocatesize_fsb -= allocated_fsb;
}
dmapi_enospc_check:
if (error == ENOSPC && (attr_flags&ATTR_DMI) == 0 &&
DM_EVENT_ENABLED(XFS_MTOVFS(mp), ip, DM_EVENT_NOSPACE)) {
error = XFS_SEND_NAMESP(mp, DM_EVENT_NOSPACE,
XFS_ITOV(ip), DM_RIGHT_NULL,
XFS_ITOV(ip), DM_RIGHT_NULL,
NULL, NULL, 0, 0, 0); /* Delay flag intentionally unused */
if (error == 0)
goto retry; /* Maybe DMAPI app. has made space */
/* else fall through with error from XFS_SEND_DATA */
}
return error;
error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
xfs_bmap_cancel(&free_list);
XFS_TRANS_UNRESERVE_QUOTA_NBLKS(mp, tp, ip, qblocks, 0, quota_flag);
error1: /* Just cancel transaction */
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
goto dmapi_enospc_check;
}
/*
* Zero file bytes between startoff and endoff inclusive.
* The iolock is held exclusive and no blocks are buffered.
*/
STATIC int
xfs_zero_remaining_bytes(
xfs_inode_t *ip,
xfs_off_t startoff,
xfs_off_t endoff)
{
xfs_bmbt_irec_t imap;
xfs_fileoff_t offset_fsb;
xfs_off_t lastoffset;
xfs_off_t offset;
xfs_buf_t *bp;
xfs_mount_t *mp = ip->i_mount;
int nimap;
int error = 0;
bp = xfs_buf_get_noaddr(mp->m_sb.sb_blocksize,
ip->i_d.di_flags & XFS_DIFLAG_REALTIME ?
mp->m_rtdev_targp : mp->m_ddev_targp);
for (offset = startoff; offset <= endoff; offset = lastoffset + 1) {
offset_fsb = XFS_B_TO_FSBT(mp, offset);
nimap = 1;
error = XFS_BMAPI(mp, NULL, &ip->i_iocore, offset_fsb, 1, 0,
NULL, 0, &imap, &nimap, NULL, NULL);
if (error || nimap < 1)
break;
ASSERT(imap.br_blockcount >= 1);
ASSERT(imap.br_startoff == offset_fsb);
lastoffset = XFS_FSB_TO_B(mp, imap.br_startoff + 1) - 1;
if (lastoffset > endoff)
lastoffset = endoff;
if (imap.br_startblock == HOLESTARTBLOCK)
continue;
ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
if (imap.br_state == XFS_EXT_UNWRITTEN)
continue;
XFS_BUF_UNDONE(bp);
XFS_BUF_UNWRITE(bp);
XFS_BUF_READ(bp);
XFS_BUF_SET_ADDR(bp, XFS_FSB_TO_DB(ip, imap.br_startblock));
xfsbdstrat(mp, bp);
if ((error = xfs_iowait(bp))) {
xfs_ioerror_alert("xfs_zero_remaining_bytes(read)",
mp, bp, XFS_BUF_ADDR(bp));
break;
}
memset(XFS_BUF_PTR(bp) +
(offset - XFS_FSB_TO_B(mp, imap.br_startoff)),
0, lastoffset - offset + 1);
XFS_BUF_UNDONE(bp);
XFS_BUF_UNREAD(bp);
XFS_BUF_WRITE(bp);
xfsbdstrat(mp, bp);
if ((error = xfs_iowait(bp))) {
xfs_ioerror_alert("xfs_zero_remaining_bytes(write)",
mp, bp, XFS_BUF_ADDR(bp));
break;
}
}
xfs_buf_free(bp);
return error;
}
/*
* xfs_free_file_space()
* This routine frees disk space for the given file.
*
* This routine is only called by xfs_change_file_space
* for an UNRESVSP type call.
*
* RETURNS:
* 0 on success
* errno on error
*
*/
STATIC int
xfs_free_file_space(
xfs_inode_t *ip,
xfs_off_t offset,
xfs_off_t len,
int attr_flags)
{
bhv_vnode_t *vp;
int committed;
int done;
xfs_off_t end_dmi_offset;
xfs_fileoff_t endoffset_fsb;
int error;
xfs_fsblock_t firstfsb;
xfs_bmap_free_t free_list;
xfs_bmbt_irec_t imap;
xfs_off_t ioffset;
xfs_extlen_t mod=0;
xfs_mount_t *mp;
int nimap;
uint resblks;
uint rounding;
int rt;
xfs_fileoff_t startoffset_fsb;
xfs_trans_t *tp;
int need_iolock = 1;
vp = XFS_ITOV(ip);
mp = ip->i_mount;
vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
if ((error = XFS_QM_DQATTACH(mp, ip, 0)))
return error;
error = 0;
if (len <= 0) /* if nothing being freed */
return error;
rt = (ip->i_d.di_flags & XFS_DIFLAG_REALTIME);
startoffset_fsb = XFS_B_TO_FSB(mp, offset);
end_dmi_offset = offset + len;
endoffset_fsb = XFS_B_TO_FSBT(mp, end_dmi_offset);
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
if (offset < ip->i_size &&
(attr_flags & ATTR_DMI) == 0 &&
DM_EVENT_ENABLED(XFS_MTOVFS(mp), ip, DM_EVENT_WRITE)) {
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
if (end_dmi_offset > ip->i_size)
end_dmi_offset = ip->i_size;
error = XFS_SEND_DATA(mp, DM_EVENT_WRITE, vp,
offset, end_dmi_offset - offset,
AT_DELAY_FLAG(attr_flags), NULL);
if (error)
return error;
}
if (attr_flags & ATTR_NOLOCK)
need_iolock = 0;
if (need_iolock) {
xfs_ilock(ip, XFS_IOLOCK_EXCL);
vn_iowait(vp); /* wait for the completion of any pending DIOs */
}
rounding = max_t(uint, 1 << mp->m_sb.sb_blocklog, NBPP);
ioffset = offset & ~(rounding - 1);
if (VN_CACHED(vp) != 0) {
xfs_inval_cached_trace(&ip->i_iocore, ioffset, -1,
ctooff(offtoct(ioffset)), -1);
error = bhv_vop_flushinval_pages(vp, ctooff(offtoct(ioffset)),
-1, FI_REMAPF_LOCKED);
if (error)
goto out_unlock_iolock;
}
/*
* Need to zero the stuff we're not freeing, on disk.
* If its a realtime file & can't use unwritten extents then we
* actually need to zero the extent edges. Otherwise xfs_bunmapi
* will take care of it for us.
*/
if (rt && !XFS_SB_VERSION_HASEXTFLGBIT(&mp->m_sb)) {
nimap = 1;
error = XFS_BMAPI(mp, NULL, &ip->i_iocore, startoffset_fsb,
1, 0, NULL, 0, &imap, &nimap, NULL, NULL);
if (error)
goto out_unlock_iolock;
ASSERT(nimap == 0 || nimap == 1);
if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
xfs_daddr_t block;
ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
block = imap.br_startblock;
mod = do_div(block, mp->m_sb.sb_rextsize);
if (mod)
startoffset_fsb += mp->m_sb.sb_rextsize - mod;
}
nimap = 1;
error = XFS_BMAPI(mp, NULL, &ip->i_iocore, endoffset_fsb - 1,
1, 0, NULL, 0, &imap, &nimap, NULL, NULL);
if (error)
goto out_unlock_iolock;
ASSERT(nimap == 0 || nimap == 1);
if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
mod++;
if (mod && (mod != mp->m_sb.sb_rextsize))
endoffset_fsb -= mod;
}
}
if ((done = (endoffset_fsb <= startoffset_fsb)))
/*
* One contiguous piece to clear
*/
error = xfs_zero_remaining_bytes(ip, offset, offset + len - 1);
else {
/*
* Some full blocks, possibly two pieces to clear
*/
if (offset < XFS_FSB_TO_B(mp, startoffset_fsb))
error = xfs_zero_remaining_bytes(ip, offset,
XFS_FSB_TO_B(mp, startoffset_fsb) - 1);
if (!error &&
XFS_FSB_TO_B(mp, endoffset_fsb) < offset + len)
error = xfs_zero_remaining_bytes(ip,
XFS_FSB_TO_B(mp, endoffset_fsb),
offset + len - 1);
}
/*
* free file space until done or until there is an error
*/
resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
while (!error && !done) {
/*
* allocate and setup the transaction
*/
tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
error = xfs_trans_reserve(tp,
resblks,
XFS_WRITE_LOG_RES(mp),
0,
XFS_TRANS_PERM_LOG_RES,
XFS_WRITE_LOG_COUNT);
/*
* check for running out of space
*/
if (error) {
/*
* Free the transaction structure.
*/
ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
xfs_trans_cancel(tp, 0);
break;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
error = XFS_TRANS_RESERVE_QUOTA(mp, tp,
ip->i_udquot, ip->i_gdquot, resblks, 0,
XFS_QMOPT_RES_REGBLKS);
if (error)
goto error1;
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
/*
* issue the bunmapi() call to free the blocks
*/
XFS_BMAP_INIT(&free_list, &firstfsb);
error = XFS_BUNMAPI(mp, tp, &ip->i_iocore, startoffset_fsb,
endoffset_fsb - startoffset_fsb,
0, 2, &firstfsb, &free_list, NULL, &done);
if (error) {
goto error0;
}
/*
* complete the transaction
*/
error = xfs_bmap_finish(&tp, &free_list, &committed);
if (error) {
goto error0;
}
error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
}
out_unlock_iolock:
if (need_iolock)
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
error0:
xfs_bmap_cancel(&free_list);
error1:
xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
xfs_iunlock(ip, need_iolock ? (XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL) :
XFS_ILOCK_EXCL);
return error;
}
/*
* xfs_change_file_space()
* This routine allocates or frees disk space for the given file.
* The user specified parameters are checked for alignment and size
* limitations.
*
* RETURNS:
* 0 on success
* errno on error
*
*/
int
xfs_change_file_space(
bhv_desc_t *bdp,
int cmd,
xfs_flock64_t *bf,
xfs_off_t offset,
cred_t *credp,
int attr_flags)
{
int clrprealloc;
int error;
xfs_fsize_t fsize;
xfs_inode_t *ip;
xfs_mount_t *mp;
int setprealloc;
xfs_off_t startoffset;
xfs_off_t llen;
xfs_trans_t *tp;
bhv_vattr_t va;
bhv_vnode_t *vp;
vp = BHV_TO_VNODE(bdp);
vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
ip = XFS_BHVTOI(bdp);
mp = ip->i_mount;
/*
* must be a regular file and have write permission
*/
if (!VN_ISREG(vp))
return XFS_ERROR(EINVAL);
xfs_ilock(ip, XFS_ILOCK_SHARED);
if ((error = xfs_iaccess(ip, S_IWUSR, credp))) {
xfs_iunlock(ip, XFS_ILOCK_SHARED);
return error;
}
xfs_iunlock(ip, XFS_ILOCK_SHARED);
switch (bf->l_whence) {
case 0: /*SEEK_SET*/
break;
case 1: /*SEEK_CUR*/
bf->l_start += offset;
break;
case 2: /*SEEK_END*/
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
bf->l_start += ip->i_size;
break;
default:
return XFS_ERROR(EINVAL);
}
llen = bf->l_len > 0 ? bf->l_len - 1 : bf->l_len;
if ( (bf->l_start < 0)
|| (bf->l_start > XFS_MAXIOFFSET(mp))
|| (bf->l_start + llen < 0)
|| (bf->l_start + llen > XFS_MAXIOFFSET(mp)))
return XFS_ERROR(EINVAL);
bf->l_whence = 0;
startoffset = bf->l_start;
[XFS] Fix to prevent the notorious 'NULL files' problem after a crash. The problem that has been addressed is that of synchronising updates of the file size with writes that extend a file. Without the fix the update of a file's size, as a result of a write beyond eof, is independent of when the cached data is flushed to disk. Often the file size update would be written to the filesystem log before the data is flushed to disk. When a system crashes between these two events and the filesystem log is replayed on mount the file's size will be set but since the contents never made it to disk the file is full of holes. If some of the cached data was flushed to disk then it may just be a section of the file at the end that has holes. There are existing fixes to help alleviate this problem, particularly in the case where a file has been truncated, that force cached data to be flushed to disk when the file is closed. If the system crashes while the file(s) are still open then this flushing will never occur. The fix that we have implemented is to introduce a second file size, called the in-memory file size, that represents the current file size as viewed by the user. The existing file size, called the on-disk file size, is the one that get's written to the filesystem log and we only update it when it is safe to do so. When we write to a file beyond eof we only update the in- memory file size in the write operation. Later when the I/O operation, that flushes the cached data to disk completes, an I/O completion routine will update the on-disk file size. The on-disk file size will be updated to the maximum offset of the I/O or to the value of the in-memory file size if the I/O includes eof. SGI-PV: 958522 SGI-Modid: xfs-linux-melb:xfs-kern:28322a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 03:49:46 +00:00
fsize = ip->i_size;
/*
* XFS_IOC_RESVSP and XFS_IOC_UNRESVSP will reserve or unreserve
* file space.
* These calls do NOT zero the data space allocated to the file,
* nor do they change the file size.
*
* XFS_IOC_ALLOCSP and XFS_IOC_FREESP will allocate and free file
* space.
* These calls cause the new file data to be zeroed and the file
* size to be changed.
*/
setprealloc = clrprealloc = 0;
switch (cmd) {
case XFS_IOC_RESVSP:
case XFS_IOC_RESVSP64:
error = xfs_alloc_file_space(ip, startoffset, bf->l_len,
1, attr_flags);
if (error)
return error;
setprealloc = 1;
break;
case XFS_IOC_UNRESVSP:
case XFS_IOC_UNRESVSP64:
if ((error = xfs_free_file_space(ip, startoffset, bf->l_len,
attr_flags)))
return error;
break;
case XFS_IOC_ALLOCSP:
case XFS_IOC_ALLOCSP64:
case XFS_IOC_FREESP:
case XFS_IOC_FREESP64:
if (startoffset > fsize) {
error = xfs_alloc_file_space(ip, fsize,
startoffset - fsize, 0, attr_flags);
if (error)
break;
}
va.va_mask = XFS_AT_SIZE;
va.va_size = startoffset;
error = xfs_setattr(bdp, &va, attr_flags, credp);
if (error)
return error;
clrprealloc = 1;
break;
default:
ASSERT(0);
return XFS_ERROR(EINVAL);
}
/*
* update the inode timestamp, mode, and prealloc flag bits
*/
tp = xfs_trans_alloc(mp, XFS_TRANS_WRITEID);
if ((error = xfs_trans_reserve(tp, 0, XFS_WRITEID_LOG_RES(mp),
0, 0, 0))) {
/* ASSERT(0); */
xfs_trans_cancel(tp, 0);
return error;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
if ((attr_flags & ATTR_DMI) == 0) {
ip->i_d.di_mode &= ~S_ISUID;
/*
* Note that we don't have to worry about mandatory
* file locking being disabled here because we only
* clear the S_ISGID bit if the Group execute bit is
* on, but if it was on then mandatory locking wouldn't
* have been enabled.
*/
if (ip->i_d.di_mode & S_IXGRP)
ip->i_d.di_mode &= ~S_ISGID;
xfs_ichgtime(ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
}
if (setprealloc)
ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
else if (clrprealloc)
ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
xfs_trans_set_sync(tp);
error = xfs_trans_commit(tp, 0);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
}
bhv_vnodeops_t xfs_vnodeops = {
BHV_IDENTITY_INIT(VN_BHV_XFS,VNODE_POSITION_XFS),
.vop_open = xfs_open,
.vop_close = xfs_close,
.vop_read = xfs_read,
#ifdef HAVE_SPLICE
.vop_splice_read = xfs_splice_read,
.vop_splice_write = xfs_splice_write,
#endif
.vop_write = xfs_write,
.vop_ioctl = xfs_ioctl,
.vop_getattr = xfs_getattr,
.vop_setattr = xfs_setattr,
.vop_access = xfs_access,
.vop_lookup = xfs_lookup,
.vop_create = xfs_create,
.vop_remove = xfs_remove,
.vop_link = xfs_link,
.vop_rename = xfs_rename,
.vop_mkdir = xfs_mkdir,
.vop_rmdir = xfs_rmdir,
.vop_readdir = xfs_readdir,
.vop_symlink = xfs_symlink,
.vop_readlink = xfs_readlink,
.vop_fsync = xfs_fsync,
.vop_inactive = xfs_inactive,
.vop_fid2 = xfs_fid2,
.vop_rwlock = xfs_rwlock,
.vop_rwunlock = xfs_rwunlock,
.vop_bmap = xfs_bmap,
.vop_reclaim = xfs_reclaim,
.vop_attr_get = xfs_attr_get,
.vop_attr_set = xfs_attr_set,
.vop_attr_remove = xfs_attr_remove,
.vop_attr_list = xfs_attr_list,
.vop_link_removed = (vop_link_removed_t)fs_noval,
.vop_vnode_change = (vop_vnode_change_t)fs_noval,
.vop_tosspages = fs_tosspages,
.vop_flushinval_pages = fs_flushinval_pages,
.vop_flush_pages = fs_flush_pages,
.vop_release = xfs_release,
.vop_iflush = xfs_inode_flush,
};