blob: c5077e6326c7093d5d1230ece91b37c5bb4d1f53 [file] [log] [blame]
// 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_sb.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"
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_iflush_int(struct xfs_inode *, struct xfs_buf *);
STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
STATIC int xfs_iunlink_remove(struct xfs_trans *, 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_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
return ip->i_d.di_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_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
a = ip->i_d.di_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 (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
(ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
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_d.di_aformat == XFS_DINODE_FMT_BTREE &&
(ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
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_sem locking order:
*
* i_rwsem -> page lock -> mmap_sem
* mmap_sem -> i_mmap_lock -> page_lock
*
* The difference in mmap_sem 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_sem
* 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_sem.
*
* 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 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));
}
}
void
__xfs_iflock(
struct xfs_inode *ip)
{
wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
do {
prepare_to_wait_exclusive(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
if (xfs_isiflocked(ip))
io_schedule();
} while (!xfs_iflock_nowait(ip));
finish_wait(wq, &wait.wq_entry);
}
STATIC uint
_xfs_dic2xflags(
uint16_t di_flags,
uint64_t di_flags2,
bool has_attr)
{
uint flags = 0;
if (di_flags & XFS_DIFLAG_ANY) {
if (di_flags & XFS_DIFLAG_REALTIME)
flags |= FS_XFLAG_REALTIME;
if (di_flags & XFS_DIFLAG_PREALLOC)
flags |= FS_XFLAG_PREALLOC;
if (di_flags & XFS_DIFLAG_IMMUTABLE)
flags |= FS_XFLAG_IMMUTABLE;
if (di_flags & XFS_DIFLAG_APPEND)
flags |= FS_XFLAG_APPEND;
if (di_flags & XFS_DIFLAG_SYNC)
flags |= FS_XFLAG_SYNC;
if (di_flags & XFS_DIFLAG_NOATIME)
flags |= FS_XFLAG_NOATIME;
if (di_flags & XFS_DIFLAG_NODUMP)
flags |= FS_XFLAG_NODUMP;
if (di_flags & XFS_DIFLAG_RTINHERIT)
flags |= FS_XFLAG_RTINHERIT;
if (di_flags & XFS_DIFLAG_PROJINHERIT)
flags |= FS_XFLAG_PROJINHERIT;
if (di_flags & XFS_DIFLAG_NOSYMLINKS)
flags |= FS_XFLAG_NOSYMLINKS;
if (di_flags & XFS_DIFLAG_EXTSIZE)
flags |= FS_XFLAG_EXTSIZE;
if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
flags |= FS_XFLAG_EXTSZINHERIT;
if (di_flags & XFS_DIFLAG_NODEFRAG)
flags |= FS_XFLAG_NODEFRAG;
if (di_flags & XFS_DIFLAG_FILESTREAM)
flags |= FS_XFLAG_FILESTREAM;
}
if (di_flags2 & XFS_DIFLAG2_ANY) {
if (di_flags2 & XFS_DIFLAG2_DAX)
flags |= FS_XFLAG_DAX;
if (di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
flags |= FS_XFLAG_COWEXTSIZE;
}
if (has_attr)
flags |= FS_XFLAG_HASATTR;
return flags;
}
uint
xfs_ip2xflags(
struct xfs_inode *ip)
{
struct xfs_icdinode *dic = &ip->i_d;
return _xfs_dic2xflags(dic->di_flags, dic->di_flags2, XFS_IFORK_Q(ip));
}
/*
* 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;
}
/*
* Allocate an inode on disk and return a copy of its in-core version.
* The in-core inode is locked exclusively. Set mode, nlink, and rdev
* appropriately within the inode. The uid and gid for the inode are
* set according to the contents of the given cred structure.
*
* Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
* has a free inode available, call xfs_iget() to obtain the in-core
* version of the allocated inode. Finally, fill in the inode and
* log its initial contents. In this case, ialloc_context would be
* set to NULL.
*
* If xfs_dialloc() does not have an available inode, it will replenish
* its supply by doing an allocation. Since we can only do one
* allocation within a transaction without deadlocks, we must commit
* the current transaction before returning the inode itself.
* In this case, therefore, we will set ialloc_context and return.
* The caller should then commit the current transaction, start a new
* transaction, and call xfs_ialloc() again to actually get the inode.
*
* To ensure that some other process does not grab the inode that
* was allocated during the first call to xfs_ialloc(), this routine
* also returns the [locked] bp pointing to the head of the freelist
* as ialloc_context. The caller should hold this buffer across
* the commit and pass it back into this routine on the second call.
*
* If we are allocating quota inodes, we do not have a parent inode
* to attach to or associate with (i.e. pip == NULL) because they
* are not linked into the directory structure - they are attached
* directly to the superblock - and so have no parent.
*/
static int
xfs_ialloc(
xfs_trans_t *tp,
xfs_inode_t *pip,
umode_t mode,
xfs_nlink_t nlink,
dev_t rdev,
prid_t prid,
xfs_buf_t **ialloc_context,
xfs_inode_t **ipp)
{
struct xfs_mount *mp = tp->t_mountp;
xfs_ino_t ino;
xfs_inode_t *ip;
uint flags;
int error;
struct timespec64 tv;
struct inode *inode;
/*
* Call the space management code to pick
* the on-disk inode to be allocated.
*/
error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode,
ialloc_context, &ino);
if (error)
return error;
if (*ialloc_context || ino == NULLFSINO) {
*ipp = NULL;
return 0;
}
ASSERT(*ialloc_context == NULL);
/*
* 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.
* This is because we're setting fields here we need
* 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);
/*
* We always convert v1 inodes to v2 now - we only support filesystems
* with >= v2 inode capability, so there is no reason for ever leaving
* an inode in v1 format.
*/
if (ip->i_d.di_version == 1)
ip->i_d.di_version = 2;
inode->i_mode = mode;
set_nlink(inode, nlink);
ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
inode->i_rdev = rdev;
ip->i_d.di_projid = prid;
if (pip && XFS_INHERIT_GID(pip)) {
ip->i_d.di_gid = pip->i_d.di_gid;
if ((VFS_I(pip)->i_mode & S_ISGID) && S_ISDIR(mode))
inode->i_mode |= S_ISGID;
}
/*
* 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(xfs_gid_to_kgid(ip->i_d.di_gid))))
inode->i_mode &= ~S_ISGID;
ip->i_d.di_size = 0;
ip->i_d.di_nextents = 0;
ASSERT(ip->i_d.di_nblocks == 0);
tv = current_time(inode);
inode->i_mtime = tv;
inode->i_atime = tv;
inode->i_ctime = tv;
ip->i_d.di_extsize = 0;
ip->i_d.di_dmevmask = 0;
ip->i_d.di_dmstate = 0;
ip->i_d.di_flags = 0;
if (ip->i_d.di_version == 3) {
inode_set_iversion(inode, 1);
ip->i_d.di_flags2 = 0;
ip->i_d.di_cowextsize = 0;
ip->i_d.di_crtime = tv;
}
flags = XFS_ILOG_CORE;
switch (mode & S_IFMT) {
case S_IFIFO:
case S_IFCHR:
case S_IFBLK:
case S_IFSOCK:
ip->i_d.di_format = XFS_DINODE_FMT_DEV;
ip->i_df.if_flags = 0;
flags |= XFS_ILOG_DEV;
break;
case S_IFREG:
case S_IFDIR:
if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
uint di_flags = 0;
if (S_ISDIR(mode)) {
if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
di_flags |= XFS_DIFLAG_RTINHERIT;
if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
di_flags |= XFS_DIFLAG_EXTSZINHERIT;
ip->i_d.di_extsize = pip->i_d.di_extsize;
}
if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
di_flags |= XFS_DIFLAG_PROJINHERIT;
} else if (S_ISREG(mode)) {
if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
di_flags |= XFS_DIFLAG_REALTIME;
if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
di_flags |= XFS_DIFLAG_EXTSIZE;
ip->i_d.di_extsize = pip->i_d.di_extsize;
}
}
if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
xfs_inherit_noatime)
di_flags |= XFS_DIFLAG_NOATIME;
if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
xfs_inherit_nodump)
di_flags |= XFS_DIFLAG_NODUMP;
if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
xfs_inherit_sync)
di_flags |= XFS_DIFLAG_SYNC;
if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
xfs_inherit_nosymlinks)
di_flags |= XFS_DIFLAG_NOSYMLINKS;
if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
xfs_inherit_nodefrag)
di_flags |= XFS_DIFLAG_NODEFRAG;
if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
di_flags |= XFS_DIFLAG_FILESTREAM;
ip->i_d.di_flags |= di_flags;
}
if (pip &&
(pip->i_d.di_flags2 & XFS_DIFLAG2_ANY) &&
pip->i_d.di_version == 3 &&
ip->i_d.di_version == 3) {
uint64_t di_flags2 = 0;
if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) {
di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
ip->i_d.di_cowextsize = pip->i_d.di_cowextsize;
}
if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
di_flags2 |= XFS_DIFLAG2_DAX;
ip->i_d.di_flags2 |= di_flags2;
}
/* FALLTHROUGH */
case S_IFLNK:
ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
ip->i_df.if_flags = XFS_IFEXTENTS;
ip->i_df.if_bytes = 0;
ip->i_df.if_u1.if_root = NULL;
break;
default:
ASSERT(0);
}
/*
* Attribute fork settings for new inode.
*/
ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
ip->i_d.di_anextents = 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;
}
/*
* Allocates a new inode from disk and return a pointer to the
* incore copy. This routine will internally commit the current
* transaction and allocate a new one if the Space Manager needed
* to do an allocation to replenish the inode free-list.
*
* This routine is designed to be called from xfs_create and
* xfs_create_dir.
*
*/
int
xfs_dir_ialloc(
xfs_trans_t **tpp, /* input: current transaction;
output: may be a new transaction. */
xfs_inode_t *dp, /* directory within whose allocate
the inode. */
umode_t mode,
xfs_nlink_t nlink,
dev_t rdev,
prid_t prid, /* project id */
xfs_inode_t **ipp) /* pointer to inode; it will be
locked. */
{
xfs_trans_t *tp;
xfs_inode_t *ip;
xfs_buf_t *ialloc_context = NULL;
int code;
void *dqinfo;
uint tflags;
tp = *tpp;
ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
/*
* xfs_ialloc will return a pointer to an incore inode if
* the Space Manager has an available inode on the free
* list. Otherwise, it will do an allocation and replenish
* the freelist. Since we can only do one allocation per
* transaction without deadlocks, we will need to commit the
* current transaction and start a new one. We will then
* need to call xfs_ialloc again to get the inode.
*
* If xfs_ialloc did an allocation to replenish the freelist,
* it returns the bp containing the head of the freelist as
* ialloc_context. We will hold a lock on it across the
* transaction commit so that no other process can steal
* the inode(s) that we've just allocated.
*/
code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, &ialloc_context,
&ip);
/*
* Return an error if we were unable to allocate a new inode.
* This should only happen if we run out of space on disk or
* encounter a disk error.
*/
if (code) {
*ipp = NULL;
return code;
}
if (!ialloc_context && !ip) {
*ipp = NULL;
return -ENOSPC;
}
/*
* If the AGI buffer is non-NULL, then we were unable to get an
* inode in one operation. We need to commit the current
* transaction and call xfs_ialloc() again. It is guaranteed
* to succeed the second time.
*/
if (ialloc_context) {
/*
* Normally, xfs_trans_commit releases all the locks.
* We call bhold to hang on to the ialloc_context across
* the commit. Holding this buffer prevents any other
* processes from doing any allocations in this
* allocation group.
*/
xfs_trans_bhold(tp, ialloc_context);
/*
* We want the quota changes to be associated with the next
* transaction, NOT this one. So, detach the dqinfo from this
* and attach it to the next transaction.
*/
dqinfo = NULL;
tflags = 0;
if (tp->t_dqinfo) {
dqinfo = (void *)tp->t_dqinfo;
tp->t_dqinfo = NULL;
tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
}
code = xfs_trans_roll(&tp);
/*
* Re-attach the quota info that we detached from prev trx.
*/
if (dqinfo) {
tp->t_dqinfo = dqinfo;
tp->t_flags |= tflags;
}
if (code) {
xfs_buf_relse(ialloc_context);
*tpp = tp;
*ipp = NULL;
return code;
}
xfs_trans_bjoin(tp, ialloc_context);
/*
* Call ialloc again. Since we've locked out all
* other allocations in this allocation group,
* this call should always succeed.
*/
code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
&ialloc_context, &ip);
/*
* If we get an error at this point, return to the caller
* so that the current transaction can be aborted.
*/
if (code) {
*tpp = tp;
*ipp = NULL;
return code;
}
ASSERT(!ialloc_context && ip);
}
*ipp = ip;
*tpp = tp;
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);
ASSERT(ip->i_d.di_version > 1);
inc_nlink(VFS_I(ip));
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
}
int
xfs_create(
xfs_inode_t *dp,
struct xfs_name *name,
umode_t mode,
dev_t rdev,
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;
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, xfs_kuid_to_uid(current_fsuid()),
xfs_kgid_to_gid(current_fsgid()), 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(mp, tres, resblks, 0, 0, &tp);
if (error == -ENOSPC) {
/* flush outstanding delalloc blocks and retry */
xfs_flush_inodes(mp);
error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
}
if (error)
goto out_release_inode;
xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
unlock_dp_on_error = true;
/*
* Reserve disk quota and the inode.
*/
error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
pdqp, resblks, 1, 0);
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_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid, &ip);
if (error)
goto out_trans_cancel;
/*
* Now we join the directory inode to the transaction. We do not do it
* earlier because xfs_dir_ialloc might commit the previous transaction
* (and release all the locks). 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 ?
resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
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 (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
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);
}
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 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;
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, xfs_kuid_to_uid(current_fsuid()),
xfs_kgid_to_gid(current_fsgid()), 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(mp, tres, resblks, 0, 0, &tp);
if (error)
goto out_release_inode;
error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
pdqp, resblks, 1, 0);
if (error)
goto out_trans_cancel;
error = xfs_dir_ialloc(&tp, dp, mode, 0, 0, prid, &ip);
if (error)
goto out_trans_cancel;
if (mp->m_flags & XFS_MOUNT_WSYNC)
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);
}
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);
/*
* If we are using project inheritance, we only allow hard link
* creation in our tree when the project IDs are the same; else
* the tree quota mechanism could be circumvented.
*/
if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
tdp->i_d.di_projid != sip->i_d.di_projid)) {
error = -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) {
error = xfs_iunlink_remove(tp, sip);
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 (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
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_d.di_flags2 &= ~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 (first_unmap_block >= XFS_MAX_FILEOFF) {
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;
/*
* Duplicate the transaction that has the permanent
* reservation and commit the old transaction.
*/
error = xfs_defer_finish(&tp);
if (error)
goto out;
error = xfs_trans_roll_inode(&tp, ip);
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;
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 (mp->m_flags & XFS_MOUNT_RDONLY)
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 (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))
return 0;
/*
* If we can't get the iolock just skip truncating the blocks
* past EOF because we could deadlock with the mmap_sem
* 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)) {
error = xfs_free_eofblocks(ip);
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
if (error)
return error;
}
/* delalloc blocks after truncation means it really is dirty */
if (ip->i_delayed_blks)
xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
}
return 0;
}
/*
* 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_d.di_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_d.di_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;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, 0);
error = xfs_ifree(tp, ip);
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);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
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);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return 0;
}
/*
* xfs_inactive
*
* This is called when the vnode reference count for the vnode
* goes to zero. If the file has been unlinked, then it must
* now be truncated. Also, we clear all of the read-ahead state
* kept for the inode here since the file is now closed.
*/
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);
return;
}
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 (mp->m_flags & XFS_MOUNT_RDONLY)
return;
/* 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);
return;
}
if (S_ISREG(VFS_I(ip)->i_mode) &&
(ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
truncate = 1;
error = xfs_qm_dqattach(ip);
if (error)
return;
if (S_ISLNK(VFS_I(ip)->i_mode))
error = xfs_inactive_symlink(ip);
else if (truncate)
error = xfs_inactive_truncate(ip);
if (error)
return;
/*
* 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)
return;
}
ASSERT(!ip->i_afp);
ASSERT(ip->i_d.di_anextents == 0);
ASSERT(ip->i_d.di_forkoff == 0);
/*
* Free the inode.
*/
error = xfs_inactive_ifree(ip);
if (error)
return;
/*
* Release the dquots held by inode, if any.
*/
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,
xfs_agnumber_t agno,
struct xfs_buf *agibp,
unsigned int bucket_index,
xfs_agino_t new_agino)
{
struct xfs_agi *agi = XFS_BUF_TO_AGI(agibp);
xfs_agino_t old_value;
int offset;
ASSERT(xfs_verify_agino_or_null(tp->t_mountp, agno, new_agino));
old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]);
trace_xfs_iunlink_update_bucket(tp->t_mountp, 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_corruption_error(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,
xfs_agnumber_t agno,
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, agno, next_agino));
trace_xfs_iunlink_update_dinode(mp, 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);
xfs_inobp_check(mp, ibp);
}
/* 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,
xfs_agnumber_t agno,
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, agno, next_agino));
error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp, 0, 0);
if (error)
return error;
/* Make sure the old pointer isn't garbage. */
old_value = be32_to_cpu(dip->di_next_unlinked);
if (!xfs_verify_agino_or_null(mp, 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, agno, 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_agi *agi;
struct xfs_buf *agibp;
xfs_agino_t next_agino;
xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
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);
/* Get the agi buffer first. It ensures lock ordering on the list. */
error = xfs_read_agi(mp, tp, agno, &agibp);
if (error)
return error;
agi = XFS_BUF_TO_AGI(agibp);
/*
* 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, agno, next_agino)) {
xfs_buf_corruption_error(agibp);
return -EFSCORRUPTED;
}
if (next_agino != NULLAGINO) {
struct xfs_perag *pag;
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, agno, next_agino,
&old_agino);
if (error)
return error;
ASSERT(old_agino == NULLAGINO);
/*
* agino has been unlinked, add a backref from the next inode
* back to agino.
*/
pag = xfs_perag_get(mp, agno);
error = xfs_iunlink_add_backref(pag, agino, next_agino);
xfs_perag_put(pag);
if (error)
return error;
}
/* Point the head of the list to point to this inode. */
return xfs_iunlink_update_bucket(tp, agno, agibp, bucket_index, agino);
}
/* 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, dipp, bpp, 0, 0);
if (error) {
xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
__func__, error);
return error;
}
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,
xfs_agnumber_t agno,
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_perag *pag)
{
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, 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, 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, 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, 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_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;
struct xfs_perag *pag = NULL;
xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
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, agno, &agibp);
if (error)
return error;
agi = XFS_BUF_TO_AGI(agibp);
/*
* 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, 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, agno, 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) {
pag = xfs_perag_get(mp, agno);
error = xfs_iunlink_change_backref(pag, next_agino,
NULLAGINO);
if (error)
goto out;
}
if (head_agino == agino) {
/* Point the head of the list to the next unlinked inode. */
error = xfs_iunlink_update_bucket(tp, agno, agibp, bucket_index,
next_agino);
if (error)
goto out;
} else {
struct xfs_imap imap;
xfs_agino_t prev_agino;
if (!pag)
pag = xfs_perag_get(mp, agno);
/* We need to search the list for the inode being freed. */
error = xfs_iunlink_map_prev(tp, agno, head_agino, agino,
&prev_agino, &imap, &last_dip, &last_ibp,
pag);
if (error)
goto out;
/* Point the previous inode on the list to the next inode. */
xfs_iunlink_update_dinode(tp, agno, 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.
*/
error = xfs_iunlink_change_backref(pag, agino, next_agino);
if (error)
goto out;
}
out:
if (pag)
xfs_perag_put(pag);
return error;
}
/*
* 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(
xfs_inode_t *free_ip,
xfs_trans_t *tp,
struct xfs_icluster *xic)
{
xfs_mount_t *mp = free_ip->i_mount;
int nbufs;
int i, j;
int ioffset;
xfs_daddr_t blkno;
xfs_buf_t *bp;
xfs_inode_t *ip;
xfs_inode_log_item_t *iip;
struct xfs_log_item *lip;
struct xfs_perag *pag;
struct xfs_ino_geometry *igeo = M_IGEO(mp);
xfs_ino_t inum;
int error;
inum = xic->first_ino;
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
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, as we have to ensure that any dirty inode that we
* can't get the flush lock on is attached to the buffer.
* 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;
/*
* Walk the inodes already attached to the buffer and mark them
* stale. These will all have the flush locks held, so an
* in-memory inode walk can't lock them. By marking them all
* stale first, we will not attempt to lock them in the loop
* below as the XFS_ISTALE flag will be set.
*/
list_for_each_entry(lip, &bp->b_li_list, li_bio_list) {
if (lip->li_type == XFS_LI_INODE) {
iip = (xfs_inode_log_item_t *)lip;
ASSERT(iip->ili_logged == 1);
lip->li_cb = xfs_istale_done;
xfs_trans_ail_copy_lsn(mp->m_ail,
&iip->ili_flush_lsn,
&iip->ili_item.li_lsn);
xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
}
}
/*
* For each inode in memory attempt to add it to the inode
* buffer and set it up for being staled on buffer IO
* completion. This is safe as we've locked out tail pushing
* and flushing by locking the buffer.
*
* We have already marked every inode that was part of a
* transaction stale above, which means there is no point in
* even trying to lock them.
*/
for (i = 0; i < igeo->inodes_per_cluster; i++) {
retry:
rcu_read_lock();
ip = radix_tree_lookup(&pag->pag_ici_root,
XFS_INO_TO_AGINO(mp, (inum + i)));
/* Inode not in memory, nothing to do */
if (!ip) {
rcu_read_unlock();
continue;
}
/*
* 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 + i ||
__xfs_iflags_test(ip, XFS_ISTALE)) {
spin_unlock(&ip->i_flags_lock);
rcu_read_unlock();
continue;
}
spin_unlock(&ip->i_flags_lock);
/*
* 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)) {
rcu_read_unlock();
delay(1);
goto retry;
}
/*
* Check the inode number again in case we're
* racing with freeing in xfs_reclaim_inode().
* See the comments in that function for more
* information as to why the initial check is
* not sufficient.
*/
if (ip->i_ino != inum + i) {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
rcu_read_unlock();
continue;
}
}
rcu_read_unlock();
xfs_iflock(ip);
xfs_iflags_set(ip, XFS_ISTALE);
/*
* we don't need to attach clean inodes or those only
* with unlogged changes (which we throw away, anyway).
*/
iip = ip->i_itemp;
if (!iip || xfs_inode_clean(ip)) {
ASSERT(ip != free_ip);
xfs_ifunlock(ip);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
continue;
}
iip->ili_last_fields = iip->ili_fields;
iip->ili_fields = 0;
iip->ili_fsync_fields = 0;
iip->ili_logged = 1;
xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
&iip->ili_item.li_lsn);
xfs_buf_attach_iodone(bp, xfs_istale_done,
&iip->ili_item);
if (ip != free_ip)
xfs_iunlock(ip, XFS_ILOCK_EXCL);
}
xfs_trans_stale_inode_buf(tp, bp);
xfs_trans_binval(tp, bp);
}
xfs_perag_put(pag);
return 0;
}
/*
* Free any local-format buffers sitting around before we reset to
* extents format.
*/
static inline void
xfs_ifree_local_data(
struct xfs_inode *ip,
int whichfork)
{
struct xfs_ifork *ifp;
if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL)
return;
ifp = XFS_IFORK_PTR(ip, whichfork);
xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
}
/*
* 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)
{
int error;
struct xfs_icluster xic = { 0 };
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(VFS_I(ip)->i_nlink == 0);
ASSERT(ip->i_d.di_nextents == 0);
ASSERT(ip->i_d.di_anextents == 0);
ASSERT(ip->i_d.di_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
ASSERT(ip->i_d.di_nblocks == 0);
/*
* Pull the on-disk inode from the AGI unlinked list.
*/
error = xfs_iunlink_remove(tp, ip);
if (error)
return error;
error = xfs_difree(tp, ip->i_ino, &xic);
if (error)
return error;
xfs_ifree_local_data(ip, XFS_DATA_FORK);
xfs_ifree_local_data(ip, XFS_ATTR_FORK);
VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
ip->i_d.di_flags = 0;
ip->i_d.di_flags2 = 0;
ip->i_d.di_dmevmask = 0;
ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */
ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
/* Don't attempt to replay owner changes for a deleted inode */
ip->i_itemp->ili_fields &= ~(XFS_ILOG_AOWNER|XFS_ILOG_DOWNER);
/*
* 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(ip, tp, &xic);
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_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 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<