aboutsummaryrefslogtreecommitdiff
path: root/fs/xfs/libxfs/xfs_inode_util.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/xfs/libxfs/xfs_inode_util.c')
-rw-r--r--fs/xfs/libxfs/xfs_inode_util.c749
1 files changed, 749 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_inode_util.c b/fs/xfs/libxfs/xfs_inode_util.c
new file mode 100644
index 000000000000..032333289113
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_inode_util.c
@@ -0,0 +1,749 @@
+// 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 = pip ? xfs_get_initial_prid(pip) : 0;
+ }
+
+ 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;
+}