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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_sb.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_inode_util.h"
#include "xfs_trans.h"
#include "xfs_ialloc.h"
#include "xfs_health.h"
#include "xfs_bmap.h"
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_ag.h"
#include "xfs_iunlink_item.h"
#include "xfs_inode_item.h"
uint16_t
xfs_flags2diflags(
struct xfs_inode *ip,
unsigned int xflags)
{
/* can't set PREALLOC this way, just preserve it */
uint16_t di_flags =
(ip->i_diflags & XFS_DIFLAG_PREALLOC);
if (xflags & FS_XFLAG_IMMUTABLE)
di_flags |= XFS_DIFLAG_IMMUTABLE;
if (xflags & FS_XFLAG_APPEND)
di_flags |= XFS_DIFLAG_APPEND;
if (xflags & FS_XFLAG_SYNC)
di_flags |= XFS_DIFLAG_SYNC;
if (xflags & FS_XFLAG_NOATIME)
di_flags |= XFS_DIFLAG_NOATIME;
if (xflags & FS_XFLAG_NODUMP)
di_flags |= XFS_DIFLAG_NODUMP;
if (xflags & FS_XFLAG_NODEFRAG)
di_flags |= XFS_DIFLAG_NODEFRAG;
if (xflags & FS_XFLAG_FILESTREAM)
di_flags |= XFS_DIFLAG_FILESTREAM;
if (S_ISDIR(VFS_I(ip)->i_mode)) {
if (xflags & FS_XFLAG_RTINHERIT)
di_flags |= XFS_DIFLAG_RTINHERIT;
if (xflags & FS_XFLAG_NOSYMLINKS)
di_flags |= XFS_DIFLAG_NOSYMLINKS;
if (xflags & FS_XFLAG_EXTSZINHERIT)
di_flags |= XFS_DIFLAG_EXTSZINHERIT;
if (xflags & FS_XFLAG_PROJINHERIT)
di_flags |= XFS_DIFLAG_PROJINHERIT;
} else if (S_ISREG(VFS_I(ip)->i_mode)) {
if (xflags & FS_XFLAG_REALTIME)
di_flags |= XFS_DIFLAG_REALTIME;
if (xflags & FS_XFLAG_EXTSIZE)
di_flags |= XFS_DIFLAG_EXTSIZE;
}
return di_flags;
}
uint64_t
xfs_flags2diflags2(
struct xfs_inode *ip,
unsigned int xflags)
{
uint64_t di_flags2 =
(ip->i_diflags2 & (XFS_DIFLAG2_REFLINK |
XFS_DIFLAG2_BIGTIME |
XFS_DIFLAG2_NREXT64));
if (xflags & FS_XFLAG_DAX)
di_flags2 |= XFS_DIFLAG2_DAX;
if (xflags & FS_XFLAG_COWEXTSIZE)
di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
return di_flags2;
}
uint32_t
xfs_ip2xflags(
struct xfs_inode *ip)
{
uint32_t 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_inode_has_attr_fork(ip))
flags |= FS_XFLAG_HASATTR;
return flags;
}
prid_t
xfs_get_initial_prid(struct xfs_inode *dp)
{
if (dp->i_diflags & XFS_DIFLAG_PROJINHERIT)
return dp->i_projid;
/* Assign to the root project by default. */
return 0;
}
/* Propagate di_flags from a parent inode to a child inode. */
static inline 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 inline 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;
}
}
/*
* 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 we have parent pointers and the caller hasn't told us that the file will
* never be linked into a directory tree, we /must/ create the attr fork.
*/
static inline bool
xfs_icreate_want_attrfork(
struct xfs_mount *mp,
const struct xfs_icreate_args *args)
{
if (args->flags & XFS_ICREATE_INIT_XATTRS)
return true;
if (!(args->flags & XFS_ICREATE_UNLINKABLE) && xfs_has_parent(mp))
return true;
return false;
}
/* Initialise an inode's attributes. */
void
xfs_inode_init(
struct xfs_trans *tp,
const struct xfs_icreate_args *args,
struct xfs_inode *ip)
{
struct xfs_inode *pip = args->pip;
struct inode *dir = pip ? VFS_I(pip) : NULL;
struct xfs_mount *mp = tp->t_mountp;
struct inode *inode = VFS_I(ip);
unsigned int flags;
int times = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG |
XFS_ICHGTIME_ACCESS;
if (args->flags & XFS_ICREATE_TMPFILE)
set_nlink(inode, 0);
else if (S_ISDIR(args->mode))
set_nlink(inode, 2);
else
set_nlink(inode, 1);
inode->i_rdev = args->rdev;
if (!args->idmap || pip == NULL) {
/* creating a tree root, sb rooted, or detached file */
inode->i_uid = GLOBAL_ROOT_UID;
inode->i_gid = GLOBAL_ROOT_GID;
ip->i_projid = 0;
inode->i_mode = args->mode;
} else {
/* creating a child in the directory tree */
if (dir && !(dir->i_mode & S_ISGID) && xfs_has_grpid(mp)) {
inode_fsuid_set(inode, args->idmap);
inode->i_gid = dir->i_gid;
inode->i_mode = args->mode;
} else {
inode_init_owner(args->idmap, inode, dir, args->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) &&
!vfsgid_in_group_p(i_gid_into_vfsgid(args->idmap, inode)))
inode->i_mode &= ~S_ISGID;
ip->i_projid = xfs_get_initial_prid(pip);
}
ip->i_disk_size = 0;
ip->i_df.if_nextents = 0;
ASSERT(ip->i_nblocks == 0);
ip->i_extsize = 0;
ip->i_diflags = 0;
if (xfs_has_v3inodes(mp)) {
inode_set_iversion(inode, 1);
ip->i_cowextsize = 0;
times |= XFS_ICHGTIME_CREATE;
}
xfs_trans_ichgtime(tp, ip, times);
flags = XFS_ILOG_CORE;
switch (args->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_data = NULL;
break;
default:
ASSERT(0);
}
if (xfs_icreate_want_attrfork(mp, args)) {
ip->i_forkoff = xfs_default_attroffset(ip) >> 3;
xfs_ifork_init_attr(ip, XFS_DINODE_FMT_EXTENTS, 0);
if (!xfs_has_attr(mp)) {
spin_lock(&mp->m_sb_lock);
xfs_add_attr(mp);
spin_unlock(&mp->m_sb_lock);
xfs_log_sb(tp);
}
}
xfs_trans_log_inode(tp, ip, flags);
}
/*
* 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.
*
* Hence we keep an in-memory double linked list to link each inode on an
* unlinked list. Because there are 64 unlinked lists per AGI, keeping pointer
* based lists would require having 64 list heads in the perag, one for each
* list. This is expensive in terms of memory (think millions of AGs) and cache
* misses on lookups. Instead, use the fact that inodes on the unlinked list
* must be referenced at the VFS level to keep them on the list and hence we
* have an existence guarantee for inodes on the unlinked list.
*
* Given we have an existence guarantee, we can use lockless inode cache lookups
* to resolve aginos to xfs inodes. This means we only need 8 bytes per inode
* for the double linked unlinked list, and we don't need any extra locking to
* keep the list safe as all manipulations are done under the AGI buffer lock.
* Keeping the list up to date does not require memory allocation, just finding
* the XFS inode and updating the next/prev unlinked list aginos.
*/
/*
* Update the prev pointer of the next agino. Returns -ENOLINK if the inode
* is not in cache.
*/
static int
xfs_iunlink_update_backref(
struct xfs_perag *pag,
xfs_agino_t prev_agino,
xfs_agino_t next_agino)
{
struct xfs_inode *ip;
/* No update necessary if we are at the end of the list. */
if (next_agino == NULLAGINO)
return 0;
ip = xfs_iunlink_lookup(pag, next_agino);
if (!ip)
return -ENOLINK;
ip->i_prev_unlinked = prev_agino;
return 0;
}
/*
* 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(pag, 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);
xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
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;
}
static int
xfs_iunlink_insert_inode(
struct xfs_trans *tp,
struct xfs_perag *pag,
struct xfs_buf *agibp,
struct xfs_inode *ip)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_agi *agi = agibp->b_addr;
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;
/*
* 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(pag, next_agino)) {
xfs_buf_mark_corrupt(agibp);
xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
return -EFSCORRUPTED;
}
/*
* Update the prev pointer in the next inode to point back to this
* inode.
*/
error = xfs_iunlink_update_backref(pag, agino, next_agino);
if (error == -ENOLINK)
error = xfs_iunlink_reload_next(tp, agibp, agino, next_agino);
if (error)
return error;
if (next_agino != NULLAGINO) {
/*
* There is already another inode in the bucket, so point this
* inode to the current head of the list.
*/
error = xfs_iunlink_log_inode(tp, ip, pag, next_agino);
if (error)
return error;
ip->i_next_unlinked = next_agino;
}
/* Point the head of the list to point to this inode. */
ip->i_prev_unlinked = NULLAGINO;
return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino);
}
/*
* 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.
*/
int
xfs_iunlink(
struct xfs_trans *tp,
struct xfs_inode *ip)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_perag *pag;
struct xfs_buf *agibp;
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(pag, tp, 0, &agibp);
if (error)
goto out;
error = xfs_iunlink_insert_inode(tp, pag, agibp, ip);
out:
xfs_perag_put(pag);
return error;
}
static int
xfs_iunlink_remove_inode(
struct xfs_trans *tp,
struct xfs_perag *pag,
struct xfs_buf *agibp,
struct xfs_inode *ip)
{
struct xfs_mount *mp = tp->t_mountp;
struct xfs_agi *agi = agibp->b_addr;
xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
xfs_agino_t head_agino;
short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
int error;
trace_xfs_iunlink_remove(ip);
/*
* 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(pag, head_agino)) {
XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
agi, sizeof(*agi));
xfs_ag_mark_sick(pag, XFS_SICK_AG_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_log_inode(tp, ip, pag, NULLAGINO);
if (error)
return error;
/*
* Update the prev pointer in the next inode to point back to previous
* inode in the chain.
*/
error = xfs_iunlink_update_backref(pag, ip->i_prev_unlinked,
ip->i_next_unlinked);
if (error == -ENOLINK)
error = xfs_iunlink_reload_next(tp, agibp, ip->i_prev_unlinked,
ip->i_next_unlinked);
if (error)
return error;
if (head_agino != agino) {
struct xfs_inode *prev_ip;
prev_ip = xfs_iunlink_lookup(pag, ip->i_prev_unlinked);
if (!prev_ip) {
xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
return -EFSCORRUPTED;
}
error = xfs_iunlink_log_inode(tp, prev_ip, pag,
ip->i_next_unlinked);
prev_ip->i_next_unlinked = ip->i_next_unlinked;
} else {
/* Point the head of the list to the next unlinked inode. */
error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index,
ip->i_next_unlinked);
}
ip->i_next_unlinked = NULLAGINO;
ip->i_prev_unlinked = 0;
return error;
}
/*
* Pull the on-disk inode from the AGI unlinked list.
*/
int
xfs_iunlink_remove(
struct xfs_trans *tp,
struct xfs_perag *pag,
struct xfs_inode *ip)
{
struct xfs_buf *agibp;
int error;
trace_xfs_iunlink_remove(ip);
/* Get the agi buffer first. It ensures lock ordering on the list. */
error = xfs_read_agi(pag, tp, 0, &agibp);
if (error)
return error;
return xfs_iunlink_remove_inode(tp, pag, agibp, ip);
}
/*
* 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().
*/
int
xfs_droplink(
struct xfs_trans *tp,
struct xfs_inode *ip)
{
struct inode *inode = VFS_I(ip);
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
if (inode->i_nlink == 0) {
xfs_info_ratelimited(tp->t_mountp,
"Inode 0x%llx link count dropped below zero. Pinning link count.",
ip->i_ino);
set_nlink(inode, XFS_NLINK_PINNED);
}
if (inode->i_nlink != XFS_NLINK_PINNED)
drop_nlink(inode);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
if (inode->i_nlink)
return 0;
return xfs_iunlink(tp, ip);
}
/*
* Increment the link count on an inode & log the change.
*/
void
xfs_bumplink(
struct xfs_trans *tp,
struct xfs_inode *ip)
{
struct inode *inode = VFS_I(ip);
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
if (inode->i_nlink == XFS_NLINK_PINNED - 1)
xfs_info_ratelimited(tp->t_mountp,
"Inode 0x%llx link count exceeded maximum. Pinning link count.",
ip->i_ino);
if (inode->i_nlink != XFS_NLINK_PINNED)
inc_nlink(inode);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
}
/* Free an inode in the ondisk index and zero it out. */
int
xfs_inode_uninit(
struct xfs_trans *tp,
struct xfs_perag *pag,
struct xfs_inode *ip,
struct xfs_icluster *xic)
{
struct xfs_mount *mp = ip->i_mount;
int error;
/*
* Free the inode first so that we guarantee that the AGI lock is going
* to be taken before we remove the inode from the unlinked list. This
* makes the AGI lock -> unlinked list modification order the same as
* used in O_TMPFILE creation.
*/
error = xfs_difree(tp, pag, ip->i_ino, xic);
if (error)
return error;
error = xfs_iunlink_remove(tp, pag, ip);
if (error)
return error;
/*
* 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) {
kfree(ip->i_df.if_data);
ip->i_df.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;
/*
* 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);
return 0;
}
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