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2e973b2cd4
linux/fs/xfs/xfs_inode.c
Dave Chinner 2e973b2cd4 xfs: convert remaining mount flags to state flags 
The remaining mount flags kept in m_flags are actually runtime state
flags. These change dynamically, so they really should be updated
atomically so we don't potentially lose an update due to racing
modifications.

Convert these remaining flags to be stored in m_opstate and use
atomic bitops to set and clear the flags. This also adds a couple of
simple wrappers for common state checks - read only and shutdown.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-19 10:07:13 -07:00

3819 lines
105 KiB
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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include <linux/iversion.h>
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_defer.h"
#include "xfs_inode.h"
#include "xfs_dir2.h"
#include "xfs_attr.h"
#include "xfs_trans_space.h"
#include "xfs_trans.h"
#include "xfs_buf_item.h"
#include "xfs_inode_item.h"
#include "xfs_ialloc.h"
#include "xfs_bmap.h"
#include "xfs_bmap_util.h"
#include "xfs_errortag.h"
#include "xfs_error.h"
#include "xfs_quota.h"
#include "xfs_filestream.h"
#include "xfs_trace.h"
#include "xfs_icache.h"
#include "xfs_symlink.h"
#include "xfs_trans_priv.h"
#include "xfs_log.h"
#include "xfs_bmap_btree.h"
#include "xfs_reflink.h"
#include "xfs_ag.h"
kmem_zone_t *xfs_inode_zone;
/*
* Used in xfs_itruncate_extents(). This is the maximum number of extents
* freed from a file in a single transaction.
*/
#define XFS_ITRUNC_MAX_EXTENTS 2
STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
STATIC int xfs_iunlink_remove(struct xfs_trans *tp, struct xfs_perag *pag,
struct xfs_inode *);
/*
* helper function to extract extent size hint from inode
*/
xfs_extlen_t
xfs_get_extsz_hint(
struct xfs_inode *ip)
{
/*
* No point in aligning allocations if we need to COW to actually
* write to them.
*/
if (xfs_is_always_cow_inode(ip))
return 0;
if ((ip->i_diflags & XFS_DIFLAG_EXTSIZE) && ip->i_extsize)
return ip->i_extsize;
if (XFS_IS_REALTIME_INODE(ip))
return ip->i_mount->m_sb.sb_rextsize;
return 0;
}
/*
* Helper function to extract CoW extent size hint from inode.
* Between the extent size hint and the CoW extent size hint, we
* return the greater of the two. If the value is zero (automatic),
* use the default size.
*/
xfs_extlen_t
xfs_get_cowextsz_hint(
struct xfs_inode *ip)
{
xfs_extlen_t a, b;
a = 0;
if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
a = ip->i_cowextsize;
b = xfs_get_extsz_hint(ip);
a = max(a, b);
if (a == 0)
return XFS_DEFAULT_COWEXTSZ_HINT;
return a;
}
/*
* These two are wrapper routines around the xfs_ilock() routine used to
* centralize some grungy code. They are used in places that wish to lock the
* inode solely for reading the extents. The reason these places can't just
* call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
* bringing in of the extents from disk for a file in b-tree format. If the
* inode is in b-tree format, then we need to lock the inode exclusively until
* the extents are read in. Locking it exclusively all the time would limit
* our parallelism unnecessarily, though. What we do instead is check to see
* if the extents have been read in yet, and only lock the inode exclusively
* if they have not.
*
* The functions return a value which should be given to the corresponding
* xfs_iunlock() call.
*/
uint
xfs_ilock_data_map_shared(
struct xfs_inode *ip)
{
uint lock_mode = XFS_ILOCK_SHARED;
if (xfs_need_iread_extents(&ip->i_df))
lock_mode = XFS_ILOCK_EXCL;
xfs_ilock(ip, lock_mode);
return lock_mode;
}
uint
xfs_ilock_attr_map_shared(
struct xfs_inode *ip)
{
uint lock_mode = XFS_ILOCK_SHARED;
if (ip->i_afp && xfs_need_iread_extents(ip->i_afp))
lock_mode = XFS_ILOCK_EXCL;
xfs_ilock(ip, lock_mode);
return lock_mode;
}
/*
* In addition to i_rwsem in the VFS inode, the xfs inode contains 2
* multi-reader locks: i_mmap_lock and the i_lock. This routine allows
* various combinations of the locks to be obtained.
*
* The 3 locks should always be ordered so that the IO lock is obtained first,
* the mmap lock second and the ilock last in order to prevent deadlock.
*
* Basic locking order:
*
* i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
*
* mmap_lock locking order:
*
* i_rwsem -> page lock -> mmap_lock
* mmap_lock -> i_mmap_lock -> page_lock
*
* The difference in mmap_lock locking order mean that we cannot hold the
* i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
* fault in pages during copy in/out (for buffered IO) or require the mmap_lock
* in get_user_pages() to map the user pages into the kernel address space for
* direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
* page faults already hold the mmap_lock.
*
* Hence to serialise fully against both syscall and mmap based IO, we need to
* take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
* taken in places where we need to invalidate the page cache in a race
* free manner (e.g. truncate, hole punch and other extent manipulation
* functions).
*/
void
xfs_ilock(
xfs_inode_t *ip,
uint lock_flags)
{
trace_xfs_ilock(ip, lock_flags, _RET_IP_);
/*
* You can't set both SHARED and EXCL for the same lock,
* and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
* and XFS_ILOCK_EXCL are valid values to set in lock_flags.
*/
ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
(XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
(XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
(XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
if (lock_flags & XFS_IOLOCK_EXCL) {
down_write_nested(&VFS_I(ip)->i_rwsem,
XFS_IOLOCK_DEP(lock_flags));
} else if (lock_flags & XFS_IOLOCK_SHARED) {
down_read_nested(&VFS_I(ip)->i_rwsem,
XFS_IOLOCK_DEP(lock_flags));
}
if (lock_flags & XFS_MMAPLOCK_EXCL)
mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
else if (lock_flags & XFS_MMAPLOCK_SHARED)
mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
if (lock_flags & XFS_ILOCK_EXCL)
mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
else if (lock_flags & XFS_ILOCK_SHARED)
mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
}
/*
* This is just like xfs_ilock(), except that the caller
* is guaranteed not to sleep. It returns 1 if it gets
* the requested locks and 0 otherwise. If the IO lock is
* obtained but the inode lock cannot be, then the IO lock
* is dropped before returning.
*
* ip -- the inode being locked
* lock_flags -- this parameter indicates the inode's locks to be
* to be locked. See the comment for xfs_ilock() for a list
* of valid values.
*/
int
xfs_ilock_nowait(
xfs_inode_t *ip,
uint lock_flags)
{
trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
/*
* You can't set both SHARED and EXCL for the same lock,
* and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
* and XFS_ILOCK_EXCL are valid values to set in lock_flags.
*/
ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
(XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
(XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
(XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
if (lock_flags & XFS_IOLOCK_EXCL) {
if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
goto out;
} else if (lock_flags & XFS_IOLOCK_SHARED) {
if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
goto out;
}
if (lock_flags & XFS_MMAPLOCK_EXCL) {
if (!mrtryupdate(&ip->i_mmaplock))
goto out_undo_iolock;
} else if (lock_flags & XFS_MMAPLOCK_SHARED) {
if (!mrtryaccess(&ip->i_mmaplock))
goto out_undo_iolock;
}
if (lock_flags & XFS_ILOCK_EXCL) {
if (!mrtryupdate(&ip->i_lock))
goto out_undo_mmaplock;
} else if (lock_flags & XFS_ILOCK_SHARED) {
if (!mrtryaccess(&ip->i_lock))
goto out_undo_mmaplock;
}
return 1;
out_undo_mmaplock:
if (lock_flags & XFS_MMAPLOCK_EXCL)
mrunlock_excl(&ip->i_mmaplock);
else if (lock_flags & XFS_MMAPLOCK_SHARED)
mrunlock_shared(&ip->i_mmaplock);
out_undo_iolock:
if (lock_flags & XFS_IOLOCK_EXCL)
up_write(&VFS_I(ip)->i_rwsem);
else if (lock_flags & XFS_IOLOCK_SHARED)
up_read(&VFS_I(ip)->i_rwsem);
out:
return 0;
}
/*
* xfs_iunlock() is used to drop the inode locks acquired with
* xfs_ilock() and xfs_ilock_nowait(). The caller must pass
* in the flags given to xfs_ilock() or xfs_ilock_nowait() so
* that we know which locks to drop.
*
* ip -- the inode being unlocked
* lock_flags -- this parameter indicates the inode's locks to be
* to be unlocked. See the comment for xfs_ilock() for a list
* of valid values for this parameter.
*
*/
void
xfs_iunlock(
xfs_inode_t *ip,
uint lock_flags)
{
/*
* You can't set both SHARED and EXCL for the same lock,
* and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
* and XFS_ILOCK_EXCL are valid values to set in lock_flags.
*/
ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
(XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
(XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
(XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
ASSERT(lock_flags != 0);
if (lock_flags & XFS_IOLOCK_EXCL)
up_write(&VFS_I(ip)->i_rwsem);
else if (lock_flags & XFS_IOLOCK_SHARED)
up_read(&VFS_I(ip)->i_rwsem);
if (lock_flags & XFS_MMAPLOCK_EXCL)
mrunlock_excl(&ip->i_mmaplock);
else if (lock_flags & XFS_MMAPLOCK_SHARED)
mrunlock_shared(&ip->i_mmaplock);
if (lock_flags & XFS_ILOCK_EXCL)
mrunlock_excl(&ip->i_lock);
else if (lock_flags & XFS_ILOCK_SHARED)
mrunlock_shared(&ip->i_lock);
trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
}
/*
* give up write locks. the i/o lock cannot be held nested
* if it is being demoted.
*/
void
xfs_ilock_demote(
xfs_inode_t *ip,
uint lock_flags)
{
ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
ASSERT((lock_flags &
~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
if (lock_flags & XFS_ILOCK_EXCL)
mrdemote(&ip->i_lock);
if (lock_flags & XFS_MMAPLOCK_EXCL)
mrdemote(&ip->i_mmaplock);
if (lock_flags & XFS_IOLOCK_EXCL)
downgrade_write(&VFS_I(ip)->i_rwsem);
trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
}
#if defined(DEBUG) || defined(XFS_WARN)
int
xfs_isilocked(
xfs_inode_t *ip,
uint lock_flags)
{
if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
if (!(lock_flags & XFS_ILOCK_SHARED))
return !!ip->i_lock.mr_writer;
return rwsem_is_locked(&ip->i_lock.mr_lock);
}
if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
if (!(lock_flags & XFS_MMAPLOCK_SHARED))
return !!ip->i_mmaplock.mr_writer;
return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
}
if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
if (!(lock_flags & XFS_IOLOCK_SHARED))
return !debug_locks ||
lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
}
ASSERT(0);
return 0;
}
#endif
/*
* xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
* DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
* when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
* errors and warnings.
*/
#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
static bool
xfs_lockdep_subclass_ok(
int subclass)
{
return subclass < MAX_LOCKDEP_SUBCLASSES;
}
#else
#define xfs_lockdep_subclass_ok(subclass) (true)
#endif
/*
* Bump the subclass so xfs_lock_inodes() acquires each lock with a different
* value. This can be called for any type of inode lock combination, including
* parent locking. Care must be taken to ensure we don't overrun the subclass
* storage fields in the class mask we build.
*/
static inline int
xfs_lock_inumorder(int lock_mode, int subclass)
{
int class = 0;
ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
XFS_ILOCK_RTSUM)));
ASSERT(xfs_lockdep_subclass_ok(subclass));
if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
class += subclass << XFS_IOLOCK_SHIFT;
}
if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
class += subclass << XFS_MMAPLOCK_SHIFT;
}
if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
class += subclass << XFS_ILOCK_SHIFT;
}
return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
}
/*
* 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.
*
* xfs_lock_inodes() can only be used to lock one type of lock at a time -
* the iolock, the mmaplock or the ilock, but not more than one at a time. If we
* lock more than one at a time, lockdep will report false positives saying we
* have violated locking orders.
*/
static void
xfs_lock_inodes(
struct xfs_inode **ips,
int inodes,
uint lock_mode)
{
int attempts = 0, i, j, try_lock;
struct xfs_log_item *lp;
/*
* Currently supports between 2 and 5 inodes with exclusive locking. We
* support an arbitrary depth of locking here, but absolute limits on
* inodes depend on the type of locking and the limits placed by
* lockdep annotations in xfs_lock_inumorder. These are all checked by
* the asserts.
*/
ASSERT(ips && inodes >= 2 && inodes <= 5);
ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
XFS_ILOCK_EXCL));
ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
XFS_ILOCK_SHARED)));
ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
if (lock_mode & XFS_IOLOCK_EXCL) {
ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
} else if (lock_mode & XFS_MMAPLOCK_EXCL)
ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
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 = &ips[j]->i_itemp->ili_item;
if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags))
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) {
xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
continue;
}
/* 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)))
continue;
/*
* Unlock all previous guys and try again. xfs_iunlock will try
* to push the tail if the inode is in the AIL.
*/
attempts++;
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 */
}
i = 0;
try_lock = 0;
goto again;
}
}
/*
* xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
* the mmaplock or the ilock, but not more than one type at a time. If we lock
* more than one at a time, lockdep will report false positives saying we have
* violated locking orders. The iolock must be double-locked separately since
* we use i_rwsem for that. We now support taking one lock EXCL and the other
* SHARED.
*/
void
xfs_lock_two_inodes(
struct xfs_inode *ip0,
uint ip0_mode,
struct xfs_inode *ip1,
uint ip1_mode)
{
struct xfs_inode *temp;
uint mode_temp;
int attempts = 0;
struct xfs_log_item *lp;
ASSERT(hweight32(ip0_mode) == 1);
ASSERT(hweight32(ip1_mode) == 1);
ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
!(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
!(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
!(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
!(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
ASSERT(ip0->i_ino != ip1->i_ino);
if (ip0->i_ino > ip1->i_ino) {
temp = ip0;
ip0 = ip1;
ip1 = temp;
mode_temp = ip0_mode;
ip0_mode = ip1_mode;
ip1_mode = mode_temp;
}
again:
xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
/*
* If the first lock we have locked is in the AIL, we must TRY to get
* the second lock. If we can't get it, we must release the first one
* and try again.
*/
lp = &ip0->i_itemp->ili_item;
if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) {
if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
xfs_iunlock(ip0, ip0_mode);
if ((++attempts % 5) == 0)
delay(1); /* Don't just spin the CPU */
goto again;
}
} else {
xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
}
}
uint
xfs_ip2xflags(
struct xfs_inode *ip)
{
uint flags = 0;
if (ip->i_diflags & XFS_DIFLAG_ANY) {
if (ip->i_diflags & XFS_DIFLAG_REALTIME)
flags |= FS_XFLAG_REALTIME;
if (ip->i_diflags & XFS_DIFLAG_PREALLOC)
flags |= FS_XFLAG_PREALLOC;
if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE)
flags |= FS_XFLAG_IMMUTABLE;
if (ip->i_diflags & XFS_DIFLAG_APPEND)
flags |= FS_XFLAG_APPEND;
if (ip->i_diflags & XFS_DIFLAG_SYNC)
flags |= FS_XFLAG_SYNC;
if (ip->i_diflags & XFS_DIFLAG_NOATIME)
flags |= FS_XFLAG_NOATIME;
if (ip->i_diflags & XFS_DIFLAG_NODUMP)
flags |= FS_XFLAG_NODUMP;
if (ip->i_diflags & XFS_DIFLAG_RTINHERIT)
flags |= FS_XFLAG_RTINHERIT;
if (ip->i_diflags & XFS_DIFLAG_PROJINHERIT)
flags |= FS_XFLAG_PROJINHERIT;
if (ip->i_diflags & XFS_DIFLAG_NOSYMLINKS)
flags |= FS_XFLAG_NOSYMLINKS;
if (ip->i_diflags & XFS_DIFLAG_EXTSIZE)
flags |= FS_XFLAG_EXTSIZE;
if (ip->i_diflags & XFS_DIFLAG_EXTSZINHERIT)
flags |= FS_XFLAG_EXTSZINHERIT;
if (ip->i_diflags & XFS_DIFLAG_NODEFRAG)
flags |= FS_XFLAG_NODEFRAG;
if (ip->i_diflags & XFS_DIFLAG_FILESTREAM)
flags |= FS_XFLAG_FILESTREAM;
}
if (ip->i_diflags2 & XFS_DIFLAG2_ANY) {
if (ip->i_diflags2 & XFS_DIFLAG2_DAX)
flags |= FS_XFLAG_DAX;
if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
flags |= FS_XFLAG_COWEXTSIZE;
}
if (XFS_IFORK_Q(ip))
flags |= FS_XFLAG_HASATTR;
return flags;
}
/*
* Lookups up an inode from "name". If ci_name is not NULL, then a CI match
* is allowed, otherwise it has to be an exact match. If a CI match is found,
* ci_name->name will point to a the actual name (caller must free) or
* will be set to NULL if an exact match is found.
*/
int
xfs_lookup(
xfs_inode_t *dp,
struct xfs_name *name,
xfs_inode_t **ipp,
struct xfs_name *ci_name)
{
xfs_ino_t inum;
int error;
trace_xfs_lookup(dp, name);
if (XFS_FORCED_SHUTDOWN(dp->i_mount))
return -EIO;
error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
if (error)
goto out_unlock;
error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
if (error)
goto out_free_name;
return 0;
out_free_name:
if (ci_name)
kmem_free(ci_name->name);
out_unlock:
*ipp = NULL;
return error;
}
/* Propagate di_flags from a parent inode to a child inode. */
static void
xfs_inode_inherit_flags(
struct xfs_inode *ip,
const struct xfs_inode *pip)
{
unsigned int di_flags = 0;
xfs_failaddr_t failaddr;
umode_t mode = VFS_I(ip)->i_mode;
if (S_ISDIR(mode)) {
if (pip->i_diflags & XFS_DIFLAG_RTINHERIT)
di_flags |= XFS_DIFLAG_RTINHERIT;
if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
di_flags |= XFS_DIFLAG_EXTSZINHERIT;
ip->i_extsize = pip->i_extsize;
}
if (pip->i_diflags & XFS_DIFLAG_PROJINHERIT)
di_flags |= XFS_DIFLAG_PROJINHERIT;
} else if (S_ISREG(mode)) {
if ((pip->i_diflags & XFS_DIFLAG_RTINHERIT) &&
xfs_has_realtime(ip->i_mount))
di_flags |= XFS_DIFLAG_REALTIME;
if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
di_flags |= XFS_DIFLAG_EXTSIZE;
ip->i_extsize = pip->i_extsize;
}
}
if ((pip->i_diflags & XFS_DIFLAG_NOATIME) &&
xfs_inherit_noatime)
di_flags |= XFS_DIFLAG_NOATIME;
if ((pip->i_diflags & XFS_DIFLAG_NODUMP) &&
xfs_inherit_nodump)
di_flags |= XFS_DIFLAG_NODUMP;
if ((pip->i_diflags & XFS_DIFLAG_SYNC) &&
xfs_inherit_sync)
di_flags |= XFS_DIFLAG_SYNC;
if ((pip->i_diflags & XFS_DIFLAG_NOSYMLINKS) &&
xfs_inherit_nosymlinks)
di_flags |= XFS_DIFLAG_NOSYMLINKS;
if ((pip->i_diflags & XFS_DIFLAG_NODEFRAG) &&
xfs_inherit_nodefrag)
di_flags |= XFS_DIFLAG_NODEFRAG;
if (pip->i_diflags & XFS_DIFLAG_FILESTREAM)
di_flags |= XFS_DIFLAG_FILESTREAM;
ip->i_diflags |= di_flags;
/*
* Inode verifiers on older kernels only check that the extent size
* hint is an integer multiple of the rt extent size on realtime files.
* They did not check the hint alignment on a directory with both
* rtinherit and extszinherit flags set. If the misaligned hint is
* propagated from a directory into a new realtime file, new file
* allocations will fail due to math errors in the rt allocator and/or
* trip the verifiers. Validate the hint settings in the new file so
* that we don't let broken hints propagate.
*/
failaddr = xfs_inode_validate_extsize(ip->i_mount, ip->i_extsize,
VFS_I(ip)->i_mode, ip->i_diflags);
if (failaddr) {
ip->i_diflags &= ~(XFS_DIFLAG_EXTSIZE |
XFS_DIFLAG_EXTSZINHERIT);
ip->i_extsize = 0;
}
}
/* Propagate di_flags2 from a parent inode to a child inode. */
static void
xfs_inode_inherit_flags2(
struct xfs_inode *ip,
const struct xfs_inode *pip)
{
xfs_failaddr_t failaddr;
if (pip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) {
ip->i_diflags2 |= XFS_DIFLAG2_COWEXTSIZE;
ip->i_cowextsize = pip->i_cowextsize;
}
if (pip->i_diflags2 & XFS_DIFLAG2_DAX)
ip->i_diflags2 |= XFS_DIFLAG2_DAX;
/* Don't let invalid cowextsize hints propagate. */
failaddr = xfs_inode_validate_cowextsize(ip->i_mount, ip->i_cowextsize,
VFS_I(ip)->i_mode, ip->i_diflags, ip->i_diflags2);
if (failaddr) {
ip->i_diflags2 &= ~XFS_DIFLAG2_COWEXTSIZE;
ip->i_cowextsize = 0;
}
}
/*
* Initialise a newly allocated inode and return the in-core inode to the
* caller locked exclusively.
*/
int
xfs_init_new_inode(
struct user_namespace *mnt_userns,
struct xfs_trans *tp,
struct xfs_inode *pip,
xfs_ino_t ino,
umode_t mode,
xfs_nlink_t nlink,
dev_t rdev,
prid_t prid,
bool init_xattrs,
struct xfs_inode **ipp)
{
struct inode *dir = pip ? VFS_I(pip) : NULL;
struct xfs_mount *mp = tp->t_mountp;
struct xfs_inode *ip;
unsigned int flags;
int error;
struct timespec64 tv;
struct inode *inode;
/*
* Protect against obviously corrupt allocation btree records. Later
* xfs_iget checks will catch re-allocation of other active in-memory
* and on-disk inodes. If we don't catch reallocating the parent inode
* here we will deadlock in xfs_iget() so we have to do these checks
* first.
*/
if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) {
xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
return -EFSCORRUPTED;
}
/*
* Get the in-core inode with the lock held exclusively to prevent
* others from looking at until we're done.
*/
error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE, XFS_ILOCK_EXCL, &ip);
if (error)
return error;
ASSERT(ip != NULL);
inode = VFS_I(ip);
set_nlink(inode, nlink);
inode->i_rdev = rdev;
ip->i_projid = prid;
if (dir && !(dir->i_mode & S_ISGID) && xfs_has_grpid(mp)) {
inode_fsuid_set(inode, mnt_userns);
inode->i_gid = dir->i_gid;
inode->i_mode = mode;
} else {
inode_init_owner(mnt_userns, inode, dir, mode);
}
/*
* If the group ID of the new file does not match the effective group
* ID or one of the supplementary group IDs, the S_ISGID bit is cleared
* (and only if the irix_sgid_inherit compatibility variable is set).
*/
if (irix_sgid_inherit &&
(inode->i_mode & S_ISGID) &&
!in_group_p(i_gid_into_mnt(mnt_userns, inode)))
inode->i_mode &= ~S_ISGID;
ip->i_disk_size = 0;
ip->i_df.if_nextents = 0;
ASSERT(ip->i_nblocks == 0);
tv = current_time(inode);
inode->i_mtime = tv;
inode->i_atime = tv;
inode->i_ctime = tv;
ip->i_extsize = 0;
ip->i_diflags = 0;
if (xfs_has_v3inodes(mp)) {
inode_set_iversion(inode, 1);
ip->i_cowextsize = 0;
ip->i_crtime = tv;
}
flags = XFS_ILOG_CORE;
switch (mode & S_IFMT) {
case S_IFIFO:
case S_IFCHR:
case S_IFBLK:
case S_IFSOCK:
ip->i_df.if_format = XFS_DINODE_FMT_DEV;
flags |= XFS_ILOG_DEV;
break;
case S_IFREG:
case S_IFDIR:
if (pip && (pip->i_diflags & XFS_DIFLAG_ANY))
xfs_inode_inherit_flags(ip, pip);
if (pip && (pip->i_diflags2 & XFS_DIFLAG2_ANY))
xfs_inode_inherit_flags2(ip, pip);
fallthrough;
case S_IFLNK:
ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
ip->i_df.if_bytes = 0;
ip->i_df.if_u1.if_root = NULL;
break;
default:
ASSERT(0);
}
/*
* If we need to create attributes immediately after allocating the
* inode, initialise an empty attribute fork right now. We use the
* default fork offset for attributes here as we don't know exactly what
* size or how many attributes we might be adding. We can do this
* safely here because we know the data fork is completely empty and
* this saves us from needing to run a separate transaction to set the
* fork offset in the immediate future.
*/
if (init_xattrs && xfs_has_attr(mp)) {
ip->i_forkoff = xfs_default_attroffset(ip) >> 3;
ip->i_afp = xfs_ifork_alloc(XFS_DINODE_FMT_EXTENTS, 0);
}
/*
* Log the new values stuffed into the inode.
*/
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_log_inode(tp, ip, flags);
/* now that we have an i_mode we can setup the inode structure */
xfs_setup_inode(ip);
*ipp = ip;
return 0;
}
/*
* Decrement the link count on an inode & log the change. If this causes the
* link count to go to zero, move the inode to AGI unlinked list so that it can
* be freed when the last active reference goes away via xfs_inactive().
*/
static int /* error */
xfs_droplink(
xfs_trans_t *tp,
xfs_inode_t *ip)
{
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
drop_nlink(VFS_I(ip));
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
if (VFS_I(ip)->i_nlink)
return 0;
return xfs_iunlink(tp, ip);
}
/*
* Increment the link count on an inode & log the change.
*/
static void
xfs_bumplink(
xfs_trans_t *tp,
xfs_inode_t *ip)
{
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
inc_nlink(VFS_I(ip));
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
}
int
xfs_create(
struct user_namespace *mnt_userns,
xfs_inode_t *dp,
struct xfs_name *name,
umode_t mode,
dev_t rdev,
bool init_xattrs,
xfs_inode_t **ipp)
{
int is_dir = S_ISDIR(mode);
struct xfs_mount *mp = dp->i_mount;
struct xfs_inode *ip = NULL;
struct xfs_trans *tp = NULL;
int error;
bool unlock_dp_on_error = false;
prid_t prid;
struct xfs_dquot *udqp = NULL;
struct xfs_dquot *gdqp = NULL;
struct xfs_dquot *pdqp = NULL;
struct xfs_trans_res *tres;
uint resblks;
xfs_ino_t ino;
trace_xfs_create(dp, name);
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
prid = xfs_get_initial_prid(dp);
/*
* Make sure that we have allocated dquot(s) on disk.
*/
error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
mapped_fsgid(mnt_userns), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
&udqp, &gdqp, &pdqp);
if (error)
return error;
if (is_dir) {
resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
tres = &M_RES(mp)->tr_mkdir;
} else {
resblks = XFS_CREATE_SPACE_RES(mp, name->len);
tres = &M_RES(mp)->tr_create;
}
/*
* 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_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
&tp);
if (error == -ENOSPC) {
/* flush outstanding delalloc blocks and retry */
xfs_flush_inodes(mp);
error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp,
resblks, &tp);
}
if (error)
goto out_release_dquots;
xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
unlock_dp_on_error = true;
error = xfs_iext_count_may_overflow(dp, XFS_DATA_FORK,
XFS_IEXT_DIR_MANIP_CNT(mp));
if (error)
goto out_trans_cancel;
/*
* A newly created regular or special file just has one directory
* entry pointing to them, but a directory also the "." entry
* pointing to itself.
*/
error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
if (!error)
error = xfs_init_new_inode(mnt_userns, tp, dp, ino, mode,
is_dir ? 2 : 1, rdev, prid, init_xattrs, &ip);
if (error)
goto out_trans_cancel;
/*
* Now we join the directory inode to the transaction. We do not do it
* earlier because xfs_dialloc might commit the previous transaction
* (and release all the locks). An error from here on will result in
* the transaction cancel unlocking dp so don't do it explicitly in the
* error path.
*/
xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
unlock_dp_on_error = false;
error = xfs_dir_createname(tp, dp, name, ip->i_ino,
resblks - XFS_IALLOC_SPACE_RES(mp));
if (error) {
ASSERT(error != -ENOSPC);
goto out_trans_cancel;
}
xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
if (is_dir) {
error = xfs_dir_init(tp, ip, dp);
if (error)
goto out_trans_cancel;
xfs_bumplink(tp, dp);
}
/*
* If this is a synchronous mount, make sure that the
* create transaction goes to disk before returning to
* the user.
*/
if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
xfs_trans_set_sync(tp);
/*
* 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_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
error = xfs_trans_commit(tp);
if (error)
goto out_release_inode;
xfs_qm_dqrele(udqp);
xfs_qm_dqrele(gdqp);
xfs_qm_dqrele(pdqp);
*ipp = ip;
return 0;
out_trans_cancel:
xfs_trans_cancel(tp);
out_release_inode:
/*
* Wait until after the current transaction is aborted to finish the
* setup of the inode and release the inode. This prevents recursive
* transactions and deadlocks from xfs_inactive.
*/
if (ip) {
xfs_finish_inode_setup(ip);
xfs_irele(ip);
}
out_release_dquots:
xfs_qm_dqrele(udqp);
xfs_qm_dqrele(gdqp);
xfs_qm_dqrele(pdqp);
if (unlock_dp_on_error)
xfs_iunlock(dp, XFS_ILOCK_EXCL);
return error;
}
int
xfs_create_tmpfile(
struct user_namespace *mnt_userns,
struct xfs_inode *dp,
umode_t mode,
struct xfs_inode **ipp)
{
struct xfs_mount *mp = dp->i_mount;
struct xfs_inode *ip = NULL;
struct xfs_trans *tp = NULL;
int error;
prid_t prid;
struct xfs_dquot *udqp = NULL;
struct xfs_dquot *gdqp = NULL;
struct xfs_dquot *pdqp = NULL;
struct xfs_trans_res *tres;
uint resblks;
xfs_ino_t ino;
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
prid = xfs_get_initial_prid(dp);
/*
* Make sure that we have allocated dquot(s) on disk.
*/
error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
mapped_fsgid(mnt_userns), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
&udqp, &gdqp, &pdqp);
if (error)
return error;
resblks = XFS_IALLOC_SPACE_RES(mp);
tres = &M_RES(mp)->tr_create_tmpfile;
error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
&tp);
if (error)
goto out_release_dquots;
error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
if (!error)
error = xfs_init_new_inode(mnt_userns, tp, dp, ino, mode,
0, 0, prid, false, &ip);
if (error)
goto out_trans_cancel;
if (xfs_has_wsync(mp))
xfs_trans_set_sync(tp);
/*
* 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_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
error = xfs_iunlink(tp, ip);
if (error)
goto out_trans_cancel;
error = xfs_trans_commit(tp);
if (error)
goto out_release_inode;
xfs_qm_dqrele(udqp);
xfs_qm_dqrele(gdqp);
xfs_qm_dqrele(pdqp);
*ipp = ip;
return 0;
out_trans_cancel:
xfs_trans_cancel(tp);
out_release_inode:
/*
* Wait until after the current transaction is aborted to finish the
* setup of the inode and release the inode. This prevents recursive
* transactions and deadlocks from xfs_inactive.
*/
if (ip) {
xfs_finish_inode_setup(ip);
xfs_irele(ip);
}
out_release_dquots:
xfs_qm_dqrele(udqp);
xfs_qm_dqrele(gdqp);
xfs_qm_dqrele(pdqp);
return error;
}
int
xfs_link(
xfs_inode_t *tdp,
xfs_inode_t *sip,
struct xfs_name *target_name)
{
xfs_mount_t *mp = tdp->i_mount;
xfs_trans_t *tp;
int error;
int resblks;
trace_xfs_link(tdp, target_name);
ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
error = xfs_qm_dqattach(sip);
if (error)
goto std_return;
error = xfs_qm_dqattach(tdp);
if (error)
goto std_return;
resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
if (error == -ENOSPC) {
resblks = 0;
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
}
if (error)
goto std_return;
xfs_lock_two_inodes(sip, XFS_ILOCK_EXCL, tdp, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
error = xfs_iext_count_may_overflow(tdp, XFS_DATA_FORK,
XFS_IEXT_DIR_MANIP_CNT(mp));
if (error)
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_diflags & XFS_DIFLAG_PROJINHERIT) &&
tdp->i_projid != sip->i_projid)) {
error = -EXDEV;
goto error_return;
}
if (!resblks) {
error = xfs_dir_canenter(tp, tdp, target_name);
if (error)
goto error_return;
}
/*
* Handle initial link state of O_TMPFILE inode
*/
if (VFS_I(sip)->i_nlink == 0) {
struct xfs_perag *pag;
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, sip->i_ino));
error = xfs_iunlink_remove(tp, pag, sip);
xfs_perag_put(pag);
if (error)
goto error_return;
}
error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
resblks);
if (error)
goto error_return;
xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
xfs_bumplink(tp, sip);
/*
* If this is a synchronous mount, make sure that the
* link transaction goes to disk before returning to
* the user.
*/
if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
xfs_trans_set_sync(tp);
return xfs_trans_commit(tp);
error_return:
xfs_trans_cancel(tp);
std_return:
return error;
}
/* Clear the reflink flag and the cowblocks tag if possible. */
static void
xfs_itruncate_clear_reflink_flags(
struct xfs_inode *ip)
{
struct xfs_ifork *dfork;
struct xfs_ifork *cfork;
if (!xfs_is_reflink_inode(ip))
return;
dfork = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
cfork = XFS_IFORK_PTR(ip, XFS_COW_FORK);
if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK;
if (cfork->if_bytes == 0)
xfs_inode_clear_cowblocks_tag(ip);
}
/*
* Free up the underlying blocks past new_size. The new size must be smaller
* than the current size. This routine can be used both for the attribute and
* data fork, and does not modify the inode size, which is left to the caller.
*
* The transaction passed to this routine must have made a permanent log
* reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
* given transaction and start new ones, so make sure everything involved in
* the transaction is tidy before calling here. Some transaction will be
* returned to the caller to be committed. The incoming transaction must
* already include the inode, and both inode locks must be held exclusively.
* The inode must also be "held" within the transaction. On return the inode
* will be "held" within the returned transaction. This routine does NOT
* require any disk space to be reserved for it within the transaction.
*
* If we get an error, we must return with the inode locked and linked into the
* current transaction. This keeps things simple for the higher level code,
* because it always knows that the inode is locked and held in the transaction
* that returns to it whether errors occur or not. We don't mark the inode
* dirty on error so that transactions can be easily aborted if possible.
*/
int
xfs_itruncate_extents_flags(
struct xfs_trans **tpp,
struct xfs_inode *ip,
int whichfork,
xfs_fsize_t new_size,
int flags)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_trans *tp = *tpp;
xfs_fileoff_t first_unmap_block;
xfs_filblks_t unmap_len;
int error = 0;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
xfs_isilocked(ip, XFS_IOLOCK_EXCL));
ASSERT(new_size <= XFS_ISIZE(ip));
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
ASSERT(ip->i_itemp != NULL);
ASSERT(ip->i_itemp->ili_lock_flags == 0);
ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
trace_xfs_itruncate_extents_start(ip, new_size);
flags |= xfs_bmapi_aflag(whichfork);
/*
* Since it is possible for space to become allocated beyond
* the end of the file (in a crash where the space is allocated
* but the inode size is not yet updated), simply remove any
* blocks which show up between the new EOF and the maximum
* possible file size.
*
* We have to free all the blocks to the bmbt maximum offset, even if
* the page cache can't scale that far.
*/
first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
if (!xfs_verify_fileoff(mp, first_unmap_block)) {
WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF);
return 0;
}
unmap_len = XFS_MAX_FILEOFF - first_unmap_block + 1;
while (unmap_len > 0) {
ASSERT(tp->t_firstblock == NULLFSBLOCK);
error = __xfs_bunmapi(tp, ip, first_unmap_block, &unmap_len,
flags, XFS_ITRUNC_MAX_EXTENTS);
if (error)
goto out;
/* free the just unmapped extents */
error = xfs_defer_finish(&tp);
if (error)
goto out;
}
if (whichfork == XFS_DATA_FORK) {
/* Remove all pending CoW reservations. */
error = xfs_reflink_cancel_cow_blocks(ip, &tp,
first_unmap_block, XFS_MAX_FILEOFF, true);
if (error)
goto out;
xfs_itruncate_clear_reflink_flags(ip);
}
/*
* Always re-log the inode so that our permanent transaction can keep
* on rolling it forward in the log.
*/
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
trace_xfs_itruncate_extents_end(ip, new_size);
out:
*tpp = tp;
return error;
}
int
xfs_release(
xfs_inode_t *ip)
{
xfs_mount_t *mp = ip->i_mount;
int error = 0;
if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
return 0;
/* If this is a read-only mount, don't do this (would generate I/O) */
if (xfs_is_readonly(mp))
return 0;
if (!XFS_FORCED_SHUTDOWN(mp)) {
int truncated;
/*
* 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 noticeable 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.
*/
truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
if (truncated) {
xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
if (ip->i_delayed_blks > 0) {
error = filemap_flush(VFS_I(ip)->i_mapping);
if (error)
return error;
}
}
}
if (VFS_I(ip)->i_nlink == 0)
return 0;
/*
* If we can't get the iolock just skip truncating the blocks past EOF
* because we could deadlock with the mmap_lock otherwise. We'll get
* another chance to drop them once the last reference to the inode is
* dropped, so we'll never leak blocks permanently.
*/
if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL))
return 0;
if (xfs_can_free_eofblocks(ip, false)) {
/*
* Check if the inode is being opened, written and closed
* frequently and we have delayed allocation blocks outstanding
* (e.g. streaming writes from the NFS server), truncating the
* blocks past EOF will cause fragmentation to occur.
*
* In this case don't do the truncation, but we have to be
* careful how we detect this case. Blocks beyond EOF show up as
* i_delayed_blks even when the inode is clean, so we need to
* truncate them away first before checking for a dirty release.
* Hence on the first dirty close we will still remove the
* speculative allocation, but after that we will leave it in
* place.
*/
if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
goto out_unlock;
error = xfs_free_eofblocks(ip);
if (error)
goto out_unlock;
/* delalloc blocks after truncation means it really is dirty */
if (ip->i_delayed_blks)
xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
}
out_unlock:
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
/*
* xfs_inactive_truncate
*
* Called to perform a truncate when an inode becomes unlinked.
*/
STATIC int
xfs_inactive_truncate(
struct xfs_inode *ip)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_trans *tp;
int error;
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
if (error) {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
return error;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, 0);
/*
* Log the inode size first to prevent stale data exposure in the event
* of a system crash before the truncate completes. See the related
* comment in xfs_vn_setattr_size() for details.
*/
ip->i_disk_size = 0;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
if (error)
goto error_trans_cancel;
ASSERT(ip->i_df.if_nextents == 0);
error = xfs_trans_commit(tp);
if (error)
goto error_unlock;
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return 0;
error_trans_cancel:
xfs_trans_cancel(tp);
error_unlock:
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
}
/*
* xfs_inactive_ifree()
*
* Perform the inode free when an inode is unlinked.
*/
STATIC int
xfs_inactive_ifree(
struct xfs_inode *ip)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_trans *tp;
int error;
/*
* We try to use a per-AG reservation for any block needed by the finobt
* tree, but as the finobt feature predates the per-AG reservation
* support a degraded file system might not have enough space for the
* reservation at mount time. In that case try to dip into the reserved
* pool and pray.
*
* Send a warning if the reservation does happen to fail, as the inode
* now remains allocated and sits on the unlinked list until the fs is
* repaired.
*/
if (unlikely(mp->m_finobt_nores)) {
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
&tp);
} else {
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
}
if (error) {
if (error == -ENOSPC) {
xfs_warn_ratelimited(mp,
"Failed to remove inode(s) from unlinked list. "
"Please free space, unmount and run xfs_repair.");
} else {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
}
return error;
}
/*
* We do not hold the inode locked across the entire rolling transaction
* here. We only need to hold it for the first transaction that
* xfs_ifree() builds, which may mark the inode XFS_ISTALE if the
* underlying cluster buffer is freed. Relogging an XFS_ISTALE inode
* here breaks the relationship between cluster buffer invalidation and
* stale inode invalidation on cluster buffer item journal commit
* completion, and can result in leaving dirty stale inodes hanging
* around in memory.
*
* We have no need for serialising this inode operation against other
* operations - we freed the inode and hence reallocation is required
* and that will serialise on reallocating the space the deferops need
* to free. Hence we can unlock the inode on the first commit of
* the transaction rather than roll it right through the deferops. This
* avoids relogging the XFS_ISTALE inode.
*
* We check that xfs_ifree() hasn't grown an internal transaction roll
* by asserting that the inode is still locked when it returns.
*/
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
error = xfs_ifree(tp, ip);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
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)) {
xfs_notice(mp, "%s: xfs_ifree returned error %d",
__func__, error);
xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
}
xfs_trans_cancel(tp);
return error;
}
/*
* Credit the quota account(s). The inode is gone.
*/
xfs_trans_mod_dquot_byino(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. Make sure it's not a silent error.
*/
error = xfs_trans_commit(tp);
if (error)
xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
__func__, error);
return 0;
}
/*
* Returns true if we need to update the on-disk metadata before we can free
* the memory used by this inode. Updates include freeing post-eof
* preallocations; freeing COW staging extents; and marking the inode free in
* the inobt if it is on the unlinked list.
*/
bool
xfs_inode_needs_inactive(
struct xfs_inode *ip)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_ifork *cow_ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
/*
* If the inode is already free, then there can be nothing
* to clean up here.
*/
if (VFS_I(ip)->i_mode == 0)
return false;
/* If this is a read-only mount, don't do this (would generate I/O) */
if (xfs_is_readonly(mp))
return false;
/* If the log isn't running, push inodes straight to reclaim. */
if (XFS_FORCED_SHUTDOWN(mp) || xfs_has_norecovery(mp))
return false;
/* Metadata inodes require explicit resource cleanup. */
if (xfs_is_metadata_inode(ip))
return false;
/* Want to clean out the cow blocks if there are any. */
if (cow_ifp && cow_ifp->if_bytes > 0)
return true;
/* Unlinked files must be freed. */
if (VFS_I(ip)->i_nlink == 0)
return true;
/*
* This file isn't being freed, so check if there are post-eof blocks
* to free. @force is true because we are evicting an inode from the
* cache. Post-eof blocks must be freed, lest we end up with broken
* free space accounting.
*
* Note: don't bother with iolock here since lockdep complains about
* acquiring it in reclaim context. We have the only reference to the
* inode at this point anyways.
*/
return xfs_can_free_eofblocks(ip, true);
}
/*
* 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.
*/
void
xfs_inactive(
xfs_inode_t *ip)
{
struct xfs_mount *mp;
int error;
int truncate = 0;
/*
* If the inode is already free, then there can be nothing
* to clean up here.
*/
if (VFS_I(ip)->i_mode == 0) {
ASSERT(ip->i_df.if_broot_bytes == 0);
goto out;
}
mp = ip->i_mount;
ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
/* If this is a read-only mount, don't do this (would generate I/O) */
if (xfs_is_readonly(mp))
goto out;
/* Metadata inodes require explicit resource cleanup. */
if (xfs_is_metadata_inode(ip))
goto out;
/* Try to clean out the cow blocks if there are any. */
if (xfs_inode_has_cow_data(ip))
xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
if (VFS_I(ip)->i_nlink != 0) {
/*
* force is true because we are evicting an inode from the
* cache. Post-eof blocks must be freed, lest we end up with
* broken free space accounting.
*
* Note: don't bother with iolock here since lockdep complains
* about acquiring it in reclaim context. We have the only
* reference to the inode at this point anyways.
*/
if (xfs_can_free_eofblocks(ip, true))
xfs_free_eofblocks(ip);
goto out;
}
if (S_ISREG(VFS_I(ip)->i_mode) &&
(ip->i_disk_size != 0 || XFS_ISIZE(ip) != 0 ||
ip->i_df.if_nextents > 0 || ip->i_delayed_blks > 0))
truncate = 1;
error = xfs_qm_dqattach(ip);
if (error)
goto out;
if (S_ISLNK(VFS_I(ip)->i_mode))
error = xfs_inactive_symlink(ip);
else if (truncate)
error = xfs_inactive_truncate(ip);
if (error)
goto out;
/*
* If there are attributes associated with the file then blow them away
* now. The code calls a routine that recursively deconstructs the
* attribute fork. If also blows away the in-core attribute fork.
*/
if (XFS_IFORK_Q(ip)) {
error = xfs_attr_inactive(ip);
if (error)
goto out;
}
ASSERT(!ip->i_afp);
ASSERT(ip->i_forkoff == 0);
/*
* Free the inode.
*/
xfs_inactive_ifree(ip);
out:
/*
* We're done making metadata updates for this inode, so we can release
* the attached dquots.
*/
xfs_qm_dqdetach(ip);
}
/*
* In-Core Unlinked List Lookups
* =============================
*
* Every inode is supposed to be reachable from some other piece of metadata
* with the exception of the root directory. Inodes with a connection to a
* file descriptor but not linked from anywhere in the on-disk directory tree
* are collectively known as unlinked inodes, though the filesystem itself
* maintains links to these inodes so that on-disk metadata are consistent.
*
* XFS implements a per-AG on-disk hash table of unlinked inodes. The AGI
* header contains a number of buckets that point to an inode, and each inode
* record has a pointer to the next inode in the hash chain. This
* singly-linked list causes scaling problems in the iunlink remove function
* because we must walk that list to find the inode that points to the inode
* being removed from the unlinked hash bucket list.
*
* What if we modelled the unlinked list as a collection of records capturing
* "X.next_unlinked = Y" relations? If we indexed those records on Y, we'd
* have a fast way to look up unlinked list predecessors, which avoids the
* slow list walk. That's exactly what we do here (in-core) with a per-AG
* rhashtable.
*
* Because this is a backref cache, we ignore operational failures since the
* iunlink code can fall back to the slow bucket walk. The only errors that
* should bubble out are for obviously incorrect situations.
*
* All users of the backref cache MUST hold the AGI buffer lock to serialize
* access or have otherwise provided for concurrency control.
*/
/* Capture a "X.next_unlinked = Y" relationship. */
struct xfs_iunlink {
struct rhash_head iu_rhash_head;
xfs_agino_t iu_agino; /* X */
xfs_agino_t iu_next_unlinked; /* Y */
};
/* Unlinked list predecessor lookup hashtable construction */
static int
xfs_iunlink_obj_cmpfn(
struct rhashtable_compare_arg *arg,
const void *obj)
{
const xfs_agino_t *key = arg->key;
const struct xfs_iunlink *iu = obj;
if (iu->iu_next_unlinked != *key)
return 1;
return 0;
}
static const struct rhashtable_params xfs_iunlink_hash_params = {
.min_size = XFS_AGI_UNLINKED_BUCKETS,
.key_len = sizeof(xfs_agino_t),
.key_offset = offsetof(struct xfs_iunlink,
iu_next_unlinked),
.head_offset = offsetof(struct xfs_iunlink, iu_rhash_head),
.automatic_shrinking = true,
.obj_cmpfn = xfs_iunlink_obj_cmpfn,
};
/*
* Return X, where X.next_unlinked == @agino. Returns NULLAGINO if no such
* relation is found.
*/
static xfs_agino_t
xfs_iunlink_lookup_backref(
struct xfs_perag *pag,
xfs_agino_t agino)
{
struct xfs_iunlink *iu;
iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
xfs_iunlink_hash_params);
return iu ? iu->iu_agino : NULLAGINO;
}
/*
* Take ownership of an iunlink cache entry and insert it into the hash table.
* If successful, the entry will be owned by the cache; if not, it is freed.
* Either way, the caller does not own @iu after this call.
*/
static int
xfs_iunlink_insert_backref(
struct xfs_perag *pag,
struct xfs_iunlink *iu)
{
int error;
error = rhashtable_insert_fast(&pag->pagi_unlinked_hash,
&iu->iu_rhash_head, xfs_iunlink_hash_params);
/*
* Fail loudly if there already was an entry because that's a sign of
* corruption of in-memory data. Also fail loudly if we see an error
* code we didn't anticipate from the rhashtable code. Currently we
* only anticipate ENOMEM.
*/
if (error) {
WARN(error != -ENOMEM, "iunlink cache insert error %d", error);
kmem_free(iu);
}
/*
* Absorb any runtime errors that aren't a result of corruption because
* this is a cache and we can always fall back to bucket list scanning.
*/
if (error != 0 && error != -EEXIST)
error = 0;
return error;
}
/* Remember that @prev_agino.next_unlinked = @this_agino. */
static int
xfs_iunlink_add_backref(
struct xfs_perag *pag,
xfs_agino_t prev_agino,
xfs_agino_t this_agino)
{
struct xfs_iunlink *iu;
if (XFS_TEST_ERROR(false, pag->pag_mount, XFS_ERRTAG_IUNLINK_FALLBACK))
return 0;
iu = kmem_zalloc(sizeof(*iu), KM_NOFS);
iu->iu_agino = prev_agino;
iu->iu_next_unlinked = this_agino;
return xfs_iunlink_insert_backref(pag, iu);
}
/*
* Replace X.next_unlinked = @agino with X.next_unlinked = @next_unlinked.
* If @next_unlinked is NULLAGINO, we drop the backref and exit. If there
* wasn't any such entry then we don't bother.
*/
static int
xfs_iunlink_change_backref(
struct xfs_perag *pag,
xfs_agino_t agino,
xfs_agino_t next_unlinked)
{
struct xfs_iunlink *iu;
int error;
/* Look up the old entry; if there wasn't one then exit. */
iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
xfs_iunlink_hash_params);
if (!iu)
return 0;
/*
* Remove the entry. This shouldn't ever return an error, but if we
* couldn't remove the old entry we don't want to add it again to the
* hash table, and if the entry disappeared on us then someone's
* violated the locking rules and we need to fail loudly. Either way
* we cannot remove the inode because internal state is or would have
* been corrupt.
*/
error = rhashtable_remove_fast(&pag->pagi_unlinked_hash,
&iu->iu_rhash_head, xfs_iunlink_hash_params);
if (error)
return error;
/* If there is no new next entry just free our item and return. */
if (next_unlinked == NULLAGINO) {
kmem_free(iu);
return 0;
}
/* Update the entry and re-add it to the hash table. */
iu->iu_next_unlinked = next_unlinked;
return xfs_iunlink_insert_backref(pag, iu);
}
/* Set up the in-core predecessor structures. */
int
xfs_iunlink_init(
struct xfs_perag *pag)
{
return rhashtable_init(&pag->pagi_unlinked_hash,
&xfs_iunlink_hash_params);
}
/* Free the in-core predecessor structures. */
static void
xfs_iunlink_free_item(
void *ptr,
void *arg)
{
struct xfs_iunlink *iu = ptr;
bool *freed_anything = arg;
*freed_anything = true;
kmem_free(iu);
}
void
xfs_iunlink_destroy(
struct xfs_perag *pag)
{
bool freed_anything = false;
rhashtable_free_and_destroy(&pag->pagi_unlinked_hash,
xfs_iunlink_free_item, &freed_anything);
ASSERT(freed_anything == false || XFS_FORCED_SHUTDOWN(pag->pag_mount));
}
/*
* Point the AGI unlinked bucket at an inode and log the results. The caller
* is responsible for validating the old value.
*/
STATIC int
xfs_iunlink_update_bucket(
struct xfs_trans *tp,
struct xfs_perag *pag,
struct xfs_buf *agibp,
unsigned int bucket_index,
xfs_agino_t new_agino)
{
struct xfs_agi *agi = agibp->b_addr;
xfs_agino_t old_value;
int offset;
ASSERT(xfs_verify_agino_or_null(tp->t_mountp, pag->pag_agno, new_agino));
old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]);
trace_xfs_iunlink_update_bucket(tp->t_mountp, pag->pag_agno, bucket_index,
old_value, new_agino);
/*
* We should never find the head of the list already set to the value
* passed in because either we're adding or removing ourselves from the
* head of the list.
*/
if (old_value == new_agino) {
xfs_buf_mark_corrupt(agibp);
return -EFSCORRUPTED;
}
agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino);
offset = offsetof(struct xfs_agi, agi_unlinked) +
(sizeof(xfs_agino_t) * bucket_index);
xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1);
return 0;
}
/* Set an on-disk inode's next_unlinked pointer. */
STATIC void
xfs_iunlink_update_dinode(
struct xfs_trans *tp,
struct xfs_perag *pag,
xfs_agino_t agino,
struct xfs_buf *ibp,
struct xfs_dinode *dip,
struct xfs_imap *imap,
xfs_agino_t next_agino)
{
struct xfs_mount *mp = tp->t_mountp;
int offset;
ASSERT(xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino));
trace_xfs_iunlink_update_dinode(mp, pag->pag_agno, agino,
be32_to_cpu(dip->di_next_unlinked), next_agino);
dip->di_next_unlinked = cpu_to_be32(next_agino);
offset = imap->im_boffset +
offsetof(struct xfs_dinode, di_next_unlinked);
/* need to recalc the inode CRC if appropriate */
xfs_dinode_calc_crc(mp, dip);
xfs_trans_inode_buf(tp, ibp);
xfs_trans_log_buf(tp, ibp, offset, offset + sizeof(xfs_agino_t) - 1);
}
/* Set an in-core inode's unlinked pointer and return the old value. */
STATIC int
xfs_iunlink_update_inode(
struct xfs_trans *tp,
struct xfs_inode *ip,
struct xfs_perag *pag,
xfs_agino_t next_agino,
xfs_agino_t *old_next_agino)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_dinode *dip;
struct xfs_buf *ibp;
xfs_agino_t old_value;
int error;
ASSERT(xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino));
error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &ibp);
if (error)
return error;
dip = xfs_buf_offset(ibp, ip->i_imap.im_boffset);
/* Make sure the old pointer isn't garbage. */
old_value = be32_to_cpu(dip->di_next_unlinked);
if (!xfs_verify_agino_or_null(mp, pag->pag_agno, old_value)) {
xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
sizeof(*dip), __this_address);
error = -EFSCORRUPTED;
goto out;
}
/*
* Since we're updating a linked list, we should never find that the
* current pointer is the same as the new value, unless we're
* terminating the list.
*/
*old_next_agino = old_value;
if (old_value == next_agino) {
if (next_agino != NULLAGINO) {
xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__,
dip, sizeof(*dip), __this_address);
error = -EFSCORRUPTED;
}
goto out;
}
/* Ok, update the new pointer. */
xfs_iunlink_update_dinode(tp, pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
ibp, dip, &ip->i_imap, next_agino);
return 0;
out:
xfs_trans_brelse(tp, ibp);
return error;
}
/*
* This is called when the inode's link count has gone to 0 or we are creating
* a tmpfile via O_TMPFILE. The inode @ip must have nlink == 0.
*
* We place the on-disk inode on a list in the AGI. It will be pulled from this
* list when the inode is freed.
*/
STATIC int
xfs_iunlink(
struct xfs_trans *tp,
struct xfs_inode *ip)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_perag *pag;
struct xfs_agi *agi;
struct xfs_buf *agibp;
xfs_agino_t next_agino;
xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
int error;
ASSERT(VFS_I(ip)->i_nlink == 0);
ASSERT(VFS_I(ip)->i_mode != 0);
trace_xfs_iunlink(ip);
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
/* Get the agi buffer first. It ensures lock ordering on the list. */
error = xfs_read_agi(mp, tp, pag->pag_agno, &agibp);
if (error)
goto out;
agi = agibp->b_addr;
/*
* Get the index into the agi hash table for the list this inode will
* go on. Make sure the pointer isn't garbage and that this inode
* isn't already on the list.
*/
next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
if (next_agino == agino ||
!xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino)) {
xfs_buf_mark_corrupt(agibp);
error = -EFSCORRUPTED;
goto out;
}
if (next_agino != NULLAGINO) {
xfs_agino_t old_agino;
/*
* There is already another inode in the bucket, so point this
* inode to the current head of the list.
*/
error = xfs_iunlink_update_inode(tp, ip, pag, next_agino,
&old_agino);
if (error)
goto out;
ASSERT(old_agino == NULLAGINO);
/*
* agino has been unlinked, add a backref from the next inode
* back to agino.
*/
error = xfs_iunlink_add_backref(pag, agino, next_agino);
if (error)
goto out;
}
/* Point the head of the list to point to this inode. */
error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino);
out:
xfs_perag_put(pag);
return error;
}
/* Return the imap, dinode pointer, and buffer for an inode. */
STATIC int
xfs_iunlink_map_ino(
struct xfs_trans *tp,
xfs_agnumber_t agno,
xfs_agino_t agino,
struct xfs_imap *imap,
struct xfs_dinode **dipp,
struct xfs_buf **bpp)
{
struct xfs_mount *mp = tp->t_mountp;
int error;
imap->im_blkno = 0;
error = xfs_imap(mp, tp, XFS_AGINO_TO_INO(mp, agno, agino), imap, 0);
if (error) {
xfs_warn(mp, "%s: xfs_imap returned error %d.",
__func__, error);
return error;
}
error = xfs_imap_to_bp(mp, tp, imap, bpp);
if (error) {
xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
__func__, error);
return error;
}
*dipp = xfs_buf_offset(*bpp, imap->im_boffset);
return 0;
}
/*
* Walk the unlinked chain from @head_agino until we find the inode that
* points to @target_agino. Return the inode number, map, dinode pointer,
* and inode cluster buffer of that inode as @agino, @imap, @dipp, and @bpp.
*
* @tp, @pag, @head_agino, and @target_agino are input parameters.
* @agino, @imap, @dipp, and @bpp are all output parameters.
*
* Do not call this function if @target_agino is the head of the list.
*/
STATIC int
xfs_iunlink_map_prev(
struct xfs_trans *tp,
struct xfs_perag *pag,
xfs_agino_t head_agino,
xfs_agino_t target_agino,
xfs_agino_t *agino,
struct xfs_imap *imap,
struct xfs_dinode **dipp,
struct xfs_buf **bpp)
{
struct xfs_mount *mp = tp->t_mountp;
xfs_agino_t next_agino;
int error;
ASSERT(head_agino != target_agino);
*bpp = NULL;
/* See if our backref cache can find it faster. */
*agino = xfs_iunlink_lookup_backref(pag, target_agino);
if (*agino != NULLAGINO) {
error = xfs_iunlink_map_ino(tp, pag->pag_agno, *agino, imap,
dipp, bpp);
if (error)
return error;
if (be32_to_cpu((*dipp)->di_next_unlinked) == target_agino)
return 0;
/*
* If we get here the cache contents were corrupt, so drop the
* buffer and fall back to walking the bucket list.
*/
xfs_trans_brelse(tp, *bpp);
*bpp = NULL;
WARN_ON_ONCE(1);
}
trace_xfs_iunlink_map_prev_fallback(mp, pag->pag_agno);
/* Otherwise, walk the entire bucket until we find it. */
next_agino = head_agino;
while (next_agino != target_agino) {
xfs_agino_t unlinked_agino;
if (*bpp)
xfs_trans_brelse(tp, *bpp);
*agino = next_agino;
error = xfs_iunlink_map_ino(tp, pag->pag_agno, next_agino, imap,
dipp, bpp);
if (error)
return error;
unlinked_agino = be32_to_cpu((*dipp)->di_next_unlinked);
/*
* Make sure this pointer is valid and isn't an obvious
* infinite loop.
*/
if (!xfs_verify_agino(mp, pag->pag_agno, unlinked_agino) ||
next_agino == unlinked_agino) {
XFS_CORRUPTION_ERROR(__func__,
XFS_ERRLEVEL_LOW, mp,
*dipp, sizeof(**dipp));
error = -EFSCORRUPTED;
return error;
}
next_agino = unlinked_agino;
}
return 0;
}
/*
* Pull the on-disk inode from the AGI unlinked list.
*/
STATIC int
xfs_iunlink_remove(
struct xfs_trans *tp,
struct xfs_perag *pag,
struct xfs_inode *ip)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_agi *agi;
struct xfs_buf *agibp;
struct xfs_buf *last_ibp;
struct xfs_dinode *last_dip = NULL;
xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
xfs_agino_t next_agino;
xfs_agino_t head_agino;
short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
int error;
trace_xfs_iunlink_remove(ip);
/* Get the agi buffer first. It ensures lock ordering on the list. */
error = xfs_read_agi(mp, tp, pag->pag_agno, &agibp);
if (error)
return error;
agi = agibp->b_addr;
/*
* Get the index into the agi hash table for the list this inode will
* go on. Make sure the head pointer isn't garbage.
*/
head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
if (!xfs_verify_agino(mp, pag->pag_agno, head_agino)) {
XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
agi, sizeof(*agi));
return -EFSCORRUPTED;
}
/*
* Set our inode's next_unlinked pointer to NULL and then return
* the old pointer value so that we can update whatever was previous
* to us in the list to point to whatever was next in the list.
*/
error = xfs_iunlink_update_inode(tp, ip, pag, NULLAGINO, &next_agino);
if (error)
return error;
/*
* If there was a backref pointing from the next inode back to this
* one, remove it because we've removed this inode from the list.
*
* Later, if this inode was in the middle of the list we'll update
* this inode's backref to point from the next inode.
*/
if (next_agino != NULLAGINO) {
error = xfs_iunlink_change_backref(pag, next_agino, NULLAGINO);
if (error)
return error;
}
if (head_agino != agino) {
struct xfs_imap imap;
xfs_agino_t prev_agino;
/* We need to search the list for the inode being freed. */
error = xfs_iunlink_map_prev(tp, pag, head_agino, agino,
&prev_agino, &imap, &last_dip, &last_ibp);
if (error)
return error;
/* Point the previous inode on the list to the next inode. */
xfs_iunlink_update_dinode(tp, pag, prev_agino, last_ibp,
last_dip, &imap, next_agino);
/*
* Now we deal with the backref for this inode. If this inode
* pointed at a real inode, change the backref that pointed to
* us to point to our old next. If this inode was the end of
* the list, delete the backref that pointed to us. Note that
* change_backref takes care of deleting the backref if
* next_agino is NULLAGINO.
*/
return xfs_iunlink_change_backref(agibp->b_pag, agino,
next_agino);
}
/* Point the head of the list to the next unlinked inode. */
return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index,
next_agino);
}
/*
* Look up the inode number specified and if it is not already marked XFS_ISTALE
* mark it stale. We should only find clean inodes in this lookup that aren't
* already stale.
*/
static void
xfs_ifree_mark_inode_stale(
struct xfs_perag *pag,
struct xfs_inode *free_ip,
xfs_ino_t inum)
{
struct xfs_mount *mp = pag->pag_mount;
struct xfs_inode_log_item *iip;
struct xfs_inode *ip;
retry:
rcu_read_lock();
ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, inum));
/* Inode not in memory, nothing to do */
if (!ip) {
rcu_read_unlock();
return;
}
/*
* because this is an RCU protected lookup, we could find a recently
* freed or even reallocated inode during the lookup. We need to check
* under the i_flags_lock for a valid inode here. Skip it if it is not
* valid, the wrong inode or stale.
*/
spin_lock(&ip->i_flags_lock);
if (ip->i_ino != inum || __xfs_iflags_test(ip, XFS_ISTALE))
goto out_iflags_unlock;
/*
* Don't try to lock/unlock the current inode, but we _cannot_ skip the
* other inodes that we did not find in the list attached to the buffer
* and are not already marked stale. If we can't lock it, back off and
* retry.
*/
if (ip != free_ip) {
if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
spin_unlock(&ip->i_flags_lock);
rcu_read_unlock();
delay(1);
goto retry;
}
}
ip->i_flags |= XFS_ISTALE;
/*
* If the inode is flushing, it is already attached to the buffer. All
* we needed to do here is mark the inode stale so buffer IO completion
* will remove it from the AIL.
*/
iip = ip->i_itemp;
if (__xfs_iflags_test(ip, XFS_IFLUSHING)) {
ASSERT(!list_empty(&iip->ili_item.li_bio_list));
ASSERT(iip->ili_last_fields);
goto out_iunlock;
}
/*
* Inodes not attached to the buffer can be released immediately.
* Everything else has to go through xfs_iflush_abort() on journal
* commit as the flock synchronises removal of the inode from the
* cluster buffer against inode reclaim.
*/
if (!iip || list_empty(&iip->ili_item.li_bio_list))
goto out_iunlock;
__xfs_iflags_set(ip, XFS_IFLUSHING);
spin_unlock(&ip->i_flags_lock);
rcu_read_unlock();
/* we have a dirty inode in memory that has not yet been flushed. */
spin_lock(&iip->ili_lock);
iip->ili_last_fields = iip->ili_fields;
iip->ili_fields = 0;
iip->ili_fsync_fields = 0;
spin_unlock(&iip->ili_lock);
ASSERT(iip->ili_last_fields);
if (ip != free_ip)
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return;
out_iunlock:
if (ip != free_ip)
xfs_iunlock(ip, XFS_ILOCK_EXCL);
out_iflags_unlock:
spin_unlock(&ip->i_flags_lock);
rcu_read_unlock();
}
/*
* A big issue when freeing the inode cluster is that we _cannot_ skip any
* inodes that are in memory - they all must be marked stale and attached to
* the cluster buffer.
*/
static int
xfs_ifree_cluster(
struct xfs_trans *tp,
struct xfs_perag *pag,
struct xfs_inode *free_ip,
struct xfs_icluster *xic)
{
struct xfs_mount *mp = free_ip->i_mount;
struct xfs_ino_geometry *igeo = M_IGEO(mp);
struct xfs_buf *bp;
xfs_daddr_t blkno;
xfs_ino_t inum = xic->first_ino;
int nbufs;
int i, j;
int ioffset;
int error;
nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster;
for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) {
/*
* The allocation bitmap tells us which inodes of the chunk were
* physically allocated. Skip the cluster if an inode falls into
* a sparse region.
*/
ioffset = inum - xic->first_ino;
if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
ASSERT(ioffset % igeo->inodes_per_cluster == 0);
continue;
}
blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
XFS_INO_TO_AGBNO(mp, inum));
/*
* We obtain and lock the backing buffer first in the process
* here to ensure dirty inodes attached to the buffer remain in
* the flushing state while we mark them stale.
*
* If we scan the in-memory inodes first, then buffer IO can
* complete before we get a lock on it, and hence we may fail
* to mark all the active inodes on the buffer stale.
*/
error = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
mp->m_bsize * igeo->blocks_per_cluster,
XBF_UNMAPPED, &bp);
if (error)
return error;
/*
* This buffer may not have been correctly initialised as we
* didn't read it from disk. That's not important because we are
* only using to mark the buffer as stale in the log, and to
* attach stale cached inodes on it. That means it will never be
* dispatched for IO. If it is, we want to know about it, and we
* want it to fail. We can acheive this by adding a write
* verifier to the buffer.
*/
bp->b_ops = &xfs_inode_buf_ops;
/*
* Now we need to set all the cached clean inodes as XFS_ISTALE,
* too. This requires lookups, and will skip inodes that we've
* already marked XFS_ISTALE.
*/
for (i = 0; i < igeo->inodes_per_cluster; i++)
xfs_ifree_mark_inode_stale(pag, free_ip, inum + i);
xfs_trans_stale_inode_buf(tp, bp);
xfs_trans_binval(tp, bp);
}
return 0;
}
/*
* This is called to return an inode to the inode free list.
* The inode should already be truncated to 0 length and have
* no pages associated with it. This routine also assumes that
* the inode is already a part of the transaction.
*
* The on-disk copy of the inode will have been added to the list
* of unlinked inodes in the AGI. We need to remove the inode from
* that list atomically with respect to freeing it here.
*/
int
xfs_ifree(
struct xfs_trans *tp,
struct xfs_inode *ip)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_perag *pag;
struct xfs_icluster xic = { 0 };
struct xfs_inode_log_item *iip = ip->i_itemp;
int error;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(VFS_I(ip)->i_nlink == 0);
ASSERT(ip->i_df.if_nextents == 0);
ASSERT(ip->i_disk_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
ASSERT(ip->i_nblocks == 0);
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
/*
* Pull the on-disk inode from the AGI unlinked list.
*/
error = xfs_iunlink_remove(tp, pag, ip);
if (error)
goto out;
error = xfs_difree(tp, pag, ip->i_ino, &xic);
if (error)
goto out;
/*
* Free any local-format data sitting around before we reset the
* data fork to extents format. Note that the attr fork data has
* already been freed by xfs_attr_inactive.
*/
if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
kmem_free(ip->i_df.if_u1.if_data);
ip->i_df.if_u1.if_data = NULL;
ip->i_df.if_bytes = 0;
}
VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
ip->i_diflags = 0;
ip->i_diflags2 = mp->m_ino_geo.new_diflags2;
ip->i_forkoff = 0; /* mark the attr fork not in use */
ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
if (xfs_iflags_test(ip, XFS_IPRESERVE_DM_FIELDS))
xfs_iflags_clear(ip, XFS_IPRESERVE_DM_FIELDS);
/* Don't attempt to replay owner changes for a deleted inode */
spin_lock(&iip->ili_lock);
iip->ili_fields &= ~(XFS_ILOG_AOWNER | XFS_ILOG_DOWNER);
spin_unlock(&iip->ili_lock);
/*
* Bump the generation count so no one will be confused
* by reincarnations of this inode.
*/
VFS_I(ip)->i_generation++;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
if (xic.deleted)
error = xfs_ifree_cluster(tp, pag, ip, &xic);
out:
xfs_perag_put(pag);
return error;
}
/*
* This is called to unpin an inode. The caller must have the inode locked
* in at least shared mode so that the buffer cannot be subsequently pinned
* once someone is waiting for it to be unpinned.
*/
static void
xfs_iunpin(
struct xfs_inode *ip)
{
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
/* Give the log a push to start the unpinning I/O */
xfs_log_force_seq(ip->i_mount, ip->i_itemp->ili_commit_seq, 0, NULL);
}
static void
__xfs_iunpin_wait(
struct xfs_inode *ip)
{
wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
xfs_iunpin(ip);
do {
prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
if (xfs_ipincount(ip))
io_schedule();
} while (xfs_ipincount(ip));
finish_wait(wq, &wait.wq_entry);
}
void
xfs_iunpin_wait(
struct xfs_inode *ip)
{
if (xfs_ipincount(ip))
__xfs_iunpin_wait(ip);
}
/*
* Removing an inode from the namespace involves removing the directory entry
* and dropping the link count on the inode. Removing the directory entry can
* result in locking an AGF (directory blocks were freed) and removing a link
* count can result in placing the inode on an unlinked list which results in
* locking an AGI.
*
* The big problem here is that we have an ordering constraint on AGF and AGI
* locking - inode allocation locks the AGI, then can allocate a new extent for
* new inodes, locking the AGF after the AGI. Similarly, freeing the inode
* removes the inode from the unlinked list, requiring that we lock the AGI
* first, and then freeing the inode can result in an inode chunk being freed
* and hence freeing disk space requiring that we lock an AGF.
*
* Hence the ordering that is imposed by other parts of the code is AGI before
* AGF. This means we cannot remove the directory entry before we drop the inode
* reference count and put it on the unlinked list as this results in a lock
* order of AGF then AGI, and this can deadlock against inode allocation and
* freeing. Therefore we must drop the link counts before we remove the
* directory entry.
*
* This is still safe from a transactional point of view - it is not until we
* get to xfs_defer_finish() that we have the possibility of multiple
* transactions in this operation. Hence as long as we remove the directory
* entry and drop the link count in the first transaction of the remove
* operation, there are no transactional constraints on the ordering here.
*/
int
xfs_remove(
xfs_inode_t *dp,
struct xfs_name *name,
xfs_inode_t *ip)
{
xfs_mount_t *mp = dp->i_mount;
xfs_trans_t *tp = NULL;
int is_dir = S_ISDIR(VFS_I(ip)->i_mode);
int error = 0;
uint resblks;
trace_xfs_remove(dp, name);
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
error = xfs_qm_dqattach(dp);
if (error)
goto std_return;
error = xfs_qm_dqattach(ip);
if (error)
goto std_return;
/*
* 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_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
if (error == -ENOSPC) {
resblks = 0;
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
&tp);
}
if (error) {
ASSERT(error != -ENOSPC);
goto std_return;
}
xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
/*
* If we're removing a directory perform some additional validation.
*/
if (is_dir) {
ASSERT(VFS_I(ip)->i_nlink >= 2);
if (VFS_I(ip)->i_nlink != 2) {
error = -ENOTEMPTY;
goto out_trans_cancel;
}
if (!xfs_dir_isempty(ip)) {
error = -ENOTEMPTY;
goto out_trans_cancel;
}
/* Drop the link from ip's "..". */
error = xfs_droplink(tp, dp);
if (error)
goto out_trans_cancel;
/* Drop the "." link from ip to self. */
error = xfs_droplink(tp, ip);
if (error)
goto out_trans_cancel;
/*
* Point the unlinked child directory's ".." entry to the root
* directory to eliminate back-references to inodes that may
* get freed before the child directory is closed. If the fs
* gets shrunk, this can lead to dirent inode validation errors.
*/
if (dp->i_ino != tp->t_mountp->m_sb.sb_rootino) {
error = xfs_dir_replace(tp, ip, &xfs_name_dotdot,
tp->t_mountp->m_sb.sb_rootino, 0);
if (error)
return error;
}
} else {
/*
* When removing a non-directory we need to log the parent
* inode here. For a directory this is done implicitly
* by the xfs_droplink call for the ".." entry.
*/
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
}
xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
/* Drop the link from dp to ip. */
error = xfs_droplink(tp, ip);
if (error)
goto out_trans_cancel;
error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks);
if (error) {
ASSERT(error != -ENOENT);
goto out_trans_cancel;
}
/*
* If this is a synchronous mount, make sure that the
* remove transaction goes to disk before returning to
* the user.
*/
if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
xfs_trans_set_sync(tp);
error = xfs_trans_commit(tp);
if (error)
goto std_return;
if (is_dir && xfs_inode_is_filestream(ip))
xfs_filestream_deassociate(ip);
return 0;
out_trans_cancel:
xfs_trans_cancel(tp);
std_return:
return error;
}
/*
* Enter all inodes for a rename transaction into a sorted array.
*/
#define __XFS_SORT_INODES 5
STATIC void
xfs_sort_for_rename(
struct xfs_inode *dp1, /* in: old (source) directory inode */
struct xfs_inode *dp2, /* in: new (target) directory inode */
struct xfs_inode *ip1, /* in: inode of old entry */
struct xfs_inode *ip2, /* in: inode of new entry */
struct xfs_inode *wip, /* in: whiteout inode */
struct xfs_inode **i_tab,/* out: sorted array of inodes */
int *num_inodes) /* in/out: inodes in array */
{
int i, j;
ASSERT(*num_inodes == __XFS_SORT_INODES);
memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
/*
* i_tab contains a list of pointers to inodes. We initialize
* the table here & we'll sort it. We will then use it to
* order the acquisition of the inode locks.
*
* Note that the table may contain duplicates. e.g., dp1 == dp2.
*/
i = 0;
i_tab[i++] = dp1;
i_tab[i++] = dp2;
i_tab[i++] = ip1;
if (ip2)
i_tab[i++] = ip2;
if (wip)
i_tab[i++] = wip;
*num_inodes = i;
/*
* Sort the elements via bubble sort. (Remember, there are at
* most 5 elements to sort, so this is adequate.)
*/
for (i = 0; i < *num_inodes; i++) {
for (j = 1; j < *num_inodes; j++) {
if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
struct xfs_inode *temp = i_tab[j];
i_tab[j] = i_tab[j-1];
i_tab[j-1] = temp;
}
}
}
}
static int
xfs_finish_rename(
struct xfs_trans *tp)
{
/*
* If this is a synchronous mount, make sure that the rename transaction
* goes to disk before returning to the user.
*/
if (xfs_has_wsync(tp->t_mountp) || xfs_has_dirsync(tp->t_mountp))
xfs_trans_set_sync(tp);
return xfs_trans_commit(tp);
}
/*
* xfs_cross_rename()
*
* responsible for handling RENAME_EXCHANGE flag in renameat2() syscall
*/
STATIC int
xfs_cross_rename(
struct xfs_trans *tp,
struct xfs_inode *dp1,
struct xfs_name *name1,
struct xfs_inode *ip1,
struct xfs_inode *dp2,
struct xfs_name *name2,
struct xfs_inode *ip2,
int spaceres)
{
int error = 0;
int ip1_flags = 0;
int ip2_flags = 0;
int dp2_flags = 0;
/* Swap inode number for dirent in first parent */
error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres);
if (error)
goto out_trans_abort;
/* Swap inode number for dirent in second parent */
error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres);
if (error)
goto out_trans_abort;
/*
* If we're renaming one or more directories across different parents,
* update the respective ".." entries (and link counts) to match the new
* parents.
*/
if (dp1 != dp2) {
dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
if (S_ISDIR(VFS_I(ip2)->i_mode)) {
error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
dp1->i_ino, spaceres);
if (error)
goto out_trans_abort;
/* transfer ip2 ".." reference to dp1 */
if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
error = xfs_droplink(tp, dp2);
if (error)
goto out_trans_abort;
xfs_bumplink(tp, dp1);
}
/*
* Although ip1 isn't changed here, userspace needs
* to be warned about the change, so that applications
* relying on it (like backup ones), will properly
* notify the change
*/
ip1_flags |= XFS_ICHGTIME_CHG;
ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
}
if (S_ISDIR(VFS_I(ip1)->i_mode)) {
error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
dp2->i_ino, spaceres);
if (error)
goto out_trans_abort;
/* transfer ip1 ".." reference to dp2 */
if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
error = xfs_droplink(tp, dp1);
if (error)
goto out_trans_abort;
xfs_bumplink(tp, dp2);
}
/*
* Although ip2 isn't changed here, userspace needs
* to be warned about the change, so that applications
* relying on it (like backup ones), will properly
* notify the change
*/
ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
ip2_flags |= XFS_ICHGTIME_CHG;
}
}
if (ip1_flags) {
xfs_trans_ichgtime(tp, ip1, ip1_flags);
xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
}
if (ip2_flags) {
xfs_trans_ichgtime(tp, ip2, ip2_flags);
xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
}
if (dp2_flags) {
xfs_trans_ichgtime(tp, dp2, dp2_flags);
xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
}
xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
return xfs_finish_rename(tp);
out_trans_abort:
xfs_trans_cancel(tp);
return error;
}
/*
* xfs_rename_alloc_whiteout()
*
* Return a referenced, unlinked, unlocked inode that can be used as a
* whiteout in a rename transaction. We use a tmpfile inode here so that if we
* crash between allocating the inode and linking it into the rename transaction
* recovery will free the inode and we won't leak it.
*/
static int
xfs_rename_alloc_whiteout(
struct user_namespace *mnt_userns,
struct xfs_inode *dp,
struct xfs_inode **wip)
{
struct xfs_inode *tmpfile;
int error;
error = xfs_create_tmpfile(mnt_userns, dp, S_IFCHR | WHITEOUT_MODE,
&tmpfile);
if (error)
return error;
/*
* Prepare the tmpfile inode as if it were created through the VFS.
* Complete the inode setup and flag it as linkable. nlink is already
* zero, so we can skip the drop_nlink.
*/
xfs_setup_iops(tmpfile);
xfs_finish_inode_setup(tmpfile);
VFS_I(tmpfile)->i_state |= I_LINKABLE;
*wip = tmpfile;
return 0;
}
/*
* xfs_rename
*/
int
xfs_rename(
struct user_namespace *mnt_userns,
struct xfs_inode *src_dp,
struct xfs_name *src_name,
struct xfs_inode *src_ip,
struct xfs_inode *target_dp,
struct xfs_name *target_name,
struct xfs_inode *target_ip,
unsigned int flags)
{
struct xfs_mount *mp = src_dp->i_mount;
struct xfs_trans *tp;
struct xfs_inode *wip = NULL; /* whiteout inode */
struct xfs_inode *inodes[__XFS_SORT_INODES];
int i;
int num_inodes = __XFS_SORT_INODES;
bool new_parent = (src_dp != target_dp);
bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
int spaceres;
int error;
trace_xfs_rename(src_dp, target_dp, src_name, target_name);
if ((flags & RENAME_EXCHANGE) && !target_ip)
return -EINVAL;
/*
* If we are doing a whiteout operation, allocate the whiteout inode
* we will be placing at the target and ensure the type is set
* appropriately.
*/
if (flags & RENAME_WHITEOUT) {
ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
error = xfs_rename_alloc_whiteout(mnt_userns, target_dp, &wip);
if (error)
return error;
/* setup target dirent info as whiteout */
src_name->type = XFS_DIR3_FT_CHRDEV;
}
xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
inodes, &num_inodes);
spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
if (error == -ENOSPC) {
spaceres = 0;
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
&tp);
}
if (error)
goto out_release_wip;
/*
* Attach the dquots to the inodes
*/
error = xfs_qm_vop_rename_dqattach(inodes);
if (error)
goto out_trans_cancel;
/*
* Lock all the participating inodes. Depending upon whether
* the target_name exists in the target directory, and
* whether the target directory is the same as the source
* directory, we can lock from 2 to 4 inodes.
*/
xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
/*
* Join all the inodes to the transaction. From this point on,
* we can rely on either trans_commit or trans_cancel to unlock
* them.
*/
xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
if (new_parent)
xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
if (target_ip)
xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
if (wip)
xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
/*
* If we are using project inheritance, we only allow renames
* into our tree when the project IDs are the same; else the
* tree quota mechanism would be circumvented.
*/
if (unlikely((target_dp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
target_dp->i_projid != src_ip->i_projid)) {
error = -EXDEV;
goto out_trans_cancel;
}
/* RENAME_EXCHANGE is unique from here on. */
if (flags & RENAME_EXCHANGE)
return xfs_cross_rename(tp, src_dp, src_name, src_ip,
target_dp, target_name, target_ip,
spaceres);
/*
* Check for expected errors before we dirty the transaction
* so we can return an error without a transaction abort.
*
* Extent count overflow check:
*
* From the perspective of src_dp, a rename operation is essentially a
* directory entry remove operation. Hence the only place where we check
* for extent count overflow for src_dp is in
* xfs_bmap_del_extent_real(). xfs_bmap_del_extent_real() returns
* -ENOSPC when it detects a possible extent count overflow and in
* response, the higher layers of directory handling code do the
* following:
* 1. Data/Free blocks: XFS lets these blocks linger until a
* future remove operation removes them.
* 2. Dabtree blocks: XFS swaps the blocks with the last block in the
* Leaf space and unmaps the last block.
*
* For target_dp, there are two cases depending on whether the
* destination directory entry exists or not.
*
* When destination directory entry does not exist (i.e. target_ip ==
* NULL), extent count overflow check is performed only when transaction
* has a non-zero sized space reservation associated with it. With a
* zero-sized space reservation, XFS allows a rename operation to
* continue only when the directory has sufficient free space in its
* data/leaf/free space blocks to hold the new entry.
*
* When destination directory entry exists (i.e. target_ip != NULL), all
* we need to do is change the inode number associated with the already
* existing entry. Hence there is no need to perform an extent count
* overflow check.
*/
if (target_ip == NULL) {
/*
* If there's no space reservation, check the entry will
* fit before actually inserting it.
*/
if (!spaceres) {
error = xfs_dir_canenter(tp, target_dp, target_name);
if (error)
goto out_trans_cancel;
} else {
error = xfs_iext_count_may_overflow(target_dp,
XFS_DATA_FORK,
XFS_IEXT_DIR_MANIP_CNT(mp));
if (error)
goto out_trans_cancel;
}
} else {
/*
* If target exists and it's a directory, check that whether
* it can be destroyed.
*/
if (S_ISDIR(VFS_I(target_ip)->i_mode) &&
(!xfs_dir_isempty(target_ip) ||
(VFS_I(target_ip)->i_nlink > 2))) {
error = -EEXIST;
goto out_trans_cancel;
}
}
/*
* Lock the AGI buffers we need to handle bumping the nlink of the
* whiteout inode off the unlinked list and to handle dropping the
* nlink of the target inode. Per locking order rules, do this in
* increasing AG order and before directory block allocation tries to
* grab AGFs because we grab AGIs before AGFs.
*
* The (vfs) caller must ensure that if src is a directory then
* target_ip is either null or an empty directory.
*/
for (i = 0; i < num_inodes && inodes[i] != NULL; i++) {
if (inodes[i] == wip ||
(inodes[i] == target_ip &&
(VFS_I(target_ip)->i_nlink == 1 || src_is_directory))) {
struct xfs_buf *bp;
xfs_agnumber_t agno;
agno = XFS_INO_TO_AGNO(mp, inodes[i]->i_ino);
error = xfs_read_agi(mp, tp, agno, &bp);
if (error)
goto out_trans_cancel;
}
}
/*
* Directory entry creation below may acquire the AGF. Remove
* the whiteout from the unlinked list first to preserve correct
* AGI/AGF locking order. This dirties the transaction so failures
* after this point will abort and log recovery will clean up the
* mess.
*
* For whiteouts, we need to bump the link count on the whiteout
* inode. After this point, we have a real link, clear the tmpfile
* state flag from the inode so it doesn't accidentally get misused
* in future.
*/
if (wip) {
struct xfs_perag *pag;
ASSERT(VFS_I(wip)->i_nlink == 0);
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, wip->i_ino));
error = xfs_iunlink_remove(tp, pag, wip);
xfs_perag_put(pag);
if (error)
goto out_trans_cancel;
xfs_bumplink(tp, wip);
VFS_I(wip)->i_state &= ~I_LINKABLE;
}
/*
* Set up the target.
*/
if (target_ip == NULL) {
/*
* If target does not exist and the rename crosses
* directories, adjust the target directory link count
* to account for the ".." reference from the new entry.
*/
error = xfs_dir_createname(tp, target_dp, target_name,
src_ip->i_ino, spaceres);
if (error)
goto out_trans_cancel;
xfs_trans_ichgtime(tp, target_dp,
XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
if (new_parent && src_is_directory) {
xfs_bumplink(tp, target_dp);
}
} else { /* target_ip != NULL */
/*
* Link the source inode under the target name.
* If the source inode is a directory and we are moving
* it across directories, its ".." entry will be
* inconsistent until we replace that down below.
*
* In case there is already an entry with the same
* name at the destination directory, remove it first.
*/
error = xfs_dir_replace(tp, target_dp, target_name,
src_ip->i_ino, spaceres);
if (error)
goto out_trans_cancel;
xfs_trans_ichgtime(tp, target_dp,
XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
/*
* Decrement the link count on the target since the target
* dir no longer points to it.
*/
error = xfs_droplink(tp, target_ip);
if (error)
goto out_trans_cancel;
if (src_is_directory) {
/*
* Drop the link from the old "." entry.
*/
error = xfs_droplink(tp, target_ip);
if (error)
goto out_trans_cancel;
}
} /* target_ip != NULL */
/*
* Remove the source.
*/
if (new_parent && src_is_directory) {
/*
* Rewrite the ".." entry to point to the new
* directory.
*/
error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
target_dp->i_ino, spaceres);
ASSERT(error != -EEXIST);
if (error)
goto out_trans_cancel;
}
/*
* We always want to hit the ctime on the source inode.
*
* This isn't strictly required by the standards since the source
* inode isn't really being changed, but old unix file systems did
* it and some incremental backup programs won't work without it.
*/
xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
/*
* Adjust the link count on src_dp. This is necessary when
* renaming a directory, either within one parent when
* the target existed, or across two parent directories.
*/
if (src_is_directory && (new_parent || target_ip != NULL)) {
/*
* Decrement link count on src_directory since the
* entry that's moved no longer points to it.
*/
error = xfs_droplink(tp, src_dp);
if (error)
goto out_trans_cancel;
}
/*
* For whiteouts, we only need to update the source dirent with the
* inode number of the whiteout inode rather than removing it
* altogether.
*/
if (wip) {
error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
spaceres);
} else {
/*
* NOTE: We don't need to check for extent count overflow here
* because the dir remove name code will leave the dir block in
* place if the extent count would overflow.
*/
error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
spaceres);
}
if (error)
goto out_trans_cancel;
xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
if (new_parent)
xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
error = xfs_finish_rename(tp);
if (wip)
xfs_irele(wip);
return error;
out_trans_cancel:
xfs_trans_cancel(tp);
out_release_wip:
if (wip)
xfs_irele(wip);
return error;
}
static int
xfs_iflush(
struct xfs_inode *ip,
struct xfs_buf *bp)
{
struct xfs_inode_log_item *iip = ip->i_itemp;
struct xfs_dinode *dip;
struct xfs_mount *mp = ip->i_mount;
int error;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(xfs_iflags_test(ip, XFS_IFLUSHING));
ASSERT(ip->i_df.if_format != XFS_DINODE_FMT_BTREE ||
ip->i_df.if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
ASSERT(iip->ili_item.li_buf == bp);
dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
/*
* We don't flush the inode if any of the following checks fail, but we
* do still update the log item and attach to the backing buffer as if
* the flush happened. This is a formality to facilitate predictable
* error handling as the caller will shutdown and fail the buffer.
*/
error = -EFSCORRUPTED;
if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
mp, XFS_ERRTAG_IFLUSH_1)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: Bad inode %Lu magic number 0x%x, ptr "PTR_FMT,
__func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
goto flush_out;
}
if (S_ISREG(VFS_I(ip)->i_mode)) {
if (XFS_TEST_ERROR(
ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
ip->i_df.if_format != XFS_DINODE_FMT_BTREE,
mp, XFS_ERRTAG_IFLUSH_3)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: Bad regular inode %Lu, ptr "PTR_FMT,
__func__, ip->i_ino, ip);
goto flush_out;
}
} else if (S_ISDIR(VFS_I(ip)->i_mode)) {
if (XFS_TEST_ERROR(
ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
ip->i_df.if_format != XFS_DINODE_FMT_BTREE &&
ip->i_df.if_format != XFS_DINODE_FMT_LOCAL,
mp, XFS_ERRTAG_IFLUSH_4)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: Bad directory inode %Lu, ptr "PTR_FMT,
__func__, ip->i_ino, ip);
goto flush_out;
}
}
if (XFS_TEST_ERROR(ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp) >
ip->i_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: detected corrupt incore inode %Lu, "
"total extents = %d, nblocks = %Ld, ptr "PTR_FMT,
__func__, ip->i_ino,
ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp),
ip->i_nblocks, ip);
goto flush_out;
}
if (XFS_TEST_ERROR(ip->i_forkoff > mp->m_sb.sb_inodesize,
mp, XFS_ERRTAG_IFLUSH_6)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: bad inode %Lu, forkoff 0x%x, ptr "PTR_FMT,
__func__, ip->i_ino, ip->i_forkoff, ip);
goto flush_out;
}
/*
* Inode item log recovery for v2 inodes are dependent on the flushiter
* count for correct sequencing. We bump the flush iteration count so
* we can detect flushes which postdate a log record during recovery.
* This is redundant as we now log every change and hence this can't
* happen but we need to still do it to ensure backwards compatibility
* with old kernels that predate logging all inode changes.
*/
if (!xfs_has_v3inodes(mp))
ip->i_flushiter++;
/*
* If there are inline format data / attr forks attached to this inode,
* make sure they are not corrupt.
*/
if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL &&
xfs_ifork_verify_local_data(ip))
goto flush_out;
if (ip->i_afp && ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL &&
xfs_ifork_verify_local_attr(ip))
goto flush_out;
/*
* Copy the dirty parts of the inode into the on-disk inode. We always
* copy out the core of the inode, because if the inode is dirty at all
* the core must be.
*/
xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
/* Wrap, we never let the log put out DI_MAX_FLUSH */
if (!xfs_has_v3inodes(mp)) {
if (ip->i_flushiter == DI_MAX_FLUSH)
ip->i_flushiter = 0;
}
xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
if (XFS_IFORK_Q(ip))
xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
/*
* We've recorded everything logged in the inode, so we'd like to clear
* the ili_fields bits so we don't log and flush things unnecessarily.
* However, we can't stop logging all this information until the data
* we've copied into the disk buffer is written to disk. If we did we
* might overwrite the copy of the inode in the log with all the data
* after re-logging only part of it, and in the face of a crash we
* wouldn't have all the data we need to recover.
*
* What we do is move the bits to the ili_last_fields field. When
* logging the inode, these bits are moved back to the ili_fields field.
* In the xfs_buf_inode_iodone() routine we clear ili_last_fields, since
* we know that the information those bits represent is permanently on
* disk. As long as the flush completes before the inode is logged
* again, then both ili_fields and ili_last_fields will be cleared.
*/
error = 0;
flush_out:
spin_lock(&iip->ili_lock);
iip->ili_last_fields = iip->ili_fields;
iip->ili_fields = 0;
iip->ili_fsync_fields = 0;
spin_unlock(&iip->ili_lock);
/*
* Store the current LSN of the inode so that we can tell whether the
* item has moved in the AIL from xfs_buf_inode_iodone().
*/
xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
&iip->ili_item.li_lsn);
/* generate the checksum. */
xfs_dinode_calc_crc(mp, dip);
return error;
}
/*
* Non-blocking flush of dirty inode metadata into the backing buffer.
*
* The caller must have a reference to the inode and hold the cluster buffer
* locked. The function will walk across all the inodes on the cluster buffer it
* can find and lock without blocking, and flush them to the cluster buffer.
*
* On successful flushing of at least one inode, the caller must write out the
* buffer and release it. If no inodes are flushed, -EAGAIN will be returned and
* the caller needs to release the buffer. On failure, the filesystem will be
* shut down, the buffer will have been unlocked and released, and EFSCORRUPTED
* will be returned.
*/
int
xfs_iflush_cluster(
struct xfs_buf *bp)
{
struct xfs_mount *mp = bp->b_mount;
struct xfs_log_item *lip, *n;
struct xfs_inode *ip;
struct xfs_inode_log_item *iip;
int clcount = 0;
int error = 0;
/*
* We must use the safe variant here as on shutdown xfs_iflush_abort()
* can remove itself from the list.
*/
list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) {
iip = (struct xfs_inode_log_item *)lip;
ip = iip->ili_inode;
/*
* Quick and dirty check to avoid locks if possible.
*/
if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING))
continue;
if (xfs_ipincount(ip))
continue;
/*
* The inode is still attached to the buffer, which means it is
* dirty but reclaim might try to grab it. Check carefully for
* that, and grab the ilock while still holding the i_flags_lock
* to guarantee reclaim will not be able to reclaim this inode
* once we drop the i_flags_lock.
*/
spin_lock(&ip->i_flags_lock);
ASSERT(!__xfs_iflags_test(ip, XFS_ISTALE));
if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING)) {
spin_unlock(&ip->i_flags_lock);
continue;
}
/*
* ILOCK will pin the inode against reclaim and prevent
* concurrent transactions modifying the inode while we are
* flushing the inode. If we get the lock, set the flushing
* state before we drop the i_flags_lock.
*/
if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
spin_unlock(&ip->i_flags_lock);
continue;
}
__xfs_iflags_set(ip, XFS_IFLUSHING);
spin_unlock(&ip->i_flags_lock);
/*
* Abort flushing this inode if we are shut down because the
* inode may not currently be in the AIL. This can occur when
* log I/O failure unpins the inode without inserting into the
* AIL, leaving a dirty/unpinned inode attached to the buffer
* that otherwise looks like it should be flushed.
*/
if (XFS_FORCED_SHUTDOWN(mp)) {
xfs_iunpin_wait(ip);
xfs_iflush_abort(ip);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
error = -EIO;
continue;
}
/* don't block waiting on a log force to unpin dirty inodes */
if (xfs_ipincount(ip)) {
xfs_iflags_clear(ip, XFS_IFLUSHING);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
continue;
}
if (!xfs_inode_clean(ip))
error = xfs_iflush(ip, bp);
else
xfs_iflags_clear(ip, XFS_IFLUSHING);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (error)
break;
clcount++;
}
if (error) {
bp->b_flags |= XBF_ASYNC;
xfs_buf_ioend_fail(bp);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
return error;
}
if (!clcount)
return -EAGAIN;
XFS_STATS_INC(mp, xs_icluster_flushcnt);
XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
return 0;
}
/* Release an inode. */
void
xfs_irele(
struct xfs_inode *ip)
{
trace_xfs_irele(ip, _RET_IP_);
iput(VFS_I(ip));
}
/*
* Ensure all commited transactions touching the inode are written to the log.
*/
int
xfs_log_force_inode(
struct xfs_inode *ip)
{
xfs_csn_t seq = 0;
xfs_ilock(ip, XFS_ILOCK_SHARED);
if (xfs_ipincount(ip))
seq = ip->i_itemp->ili_commit_seq;
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (!seq)
return 0;
return xfs_log_force_seq(ip->i_mount, seq, XFS_LOG_SYNC, NULL);
}
/*
* Grab the exclusive iolock for a data copy from src to dest, making sure to
* abide vfs locking order (lowest pointer value goes first) and breaking the
* layout leases before proceeding. The loop is needed because we cannot call
* the blocking break_layout() with the iolocks held, and therefore have to
* back out both locks.
*/
static int
xfs_iolock_two_inodes_and_break_layout(
struct inode *src,
struct inode *dest)
{
int error;
if (src > dest)
swap(src, dest);
retry:
/* Wait to break both inodes' layouts before we start locking. */
error = break_layout(src, true);
if (error)
return error;
if (src != dest) {
error = break_layout(dest, true);
if (error)
return error;
}
/* Lock one inode and make sure nobody got in and leased it. */
inode_lock(src);
error = break_layout(src, false);
if (error) {
inode_unlock(src);
if (error == -EWOULDBLOCK)
goto retry;
return error;
}
if (src == dest)
return 0;
/* Lock the other inode and make sure nobody got in and leased it. */
inode_lock_nested(dest, I_MUTEX_NONDIR2);
error = break_layout(dest, false);
if (error) {
inode_unlock(src);
inode_unlock(dest);
if (error == -EWOULDBLOCK)
goto retry;
return error;
}
return 0;
}
/*
* Lock two inodes so that userspace cannot initiate I/O via file syscalls or
* mmap activity.
*/
int
xfs_ilock2_io_mmap(
struct xfs_inode *ip1,
struct xfs_inode *ip2)
{
int ret;
ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
if (ret)
return ret;
if (ip1 == ip2)
xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
else
xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL,
ip2, XFS_MMAPLOCK_EXCL);
return 0;
}
/* Unlock both inodes to allow IO and mmap activity. */
void
xfs_iunlock2_io_mmap(
struct xfs_inode *ip1,
struct xfs_inode *ip2)
{
bool same_inode = (ip1 == ip2);
xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
if (!same_inode)
xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
inode_unlock(VFS_I(ip2));
if (!same_inode)
inode_unlock(VFS_I(ip1));
}
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