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Diffstat (limited to 'fs/xfs/scrub/parent.c')
-rw-r--r--fs/xfs/scrub/parent.c700
1 files changed, 699 insertions, 1 deletions
diff --git a/fs/xfs/scrub/parent.c b/fs/xfs/scrub/parent.c
index 7db8736721..733c410a22 100644
--- a/fs/xfs/scrub/parent.c
+++ b/fs/xfs/scrub/parent.c
@@ -10,19 +10,37 @@
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_log_format.h"
+#include "xfs_trans.h"
#include "xfs_inode.h"
#include "xfs_icache.h"
#include "xfs_dir2.h"
#include "xfs_dir2_priv.h"
+#include "xfs_attr.h"
+#include "xfs_parent.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/readdir.h"
+#include "scrub/tempfile.h"
+#include "scrub/repair.h"
+#include "scrub/listxattr.h"
+#include "scrub/xfile.h"
+#include "scrub/xfarray.h"
+#include "scrub/xfblob.h"
+#include "scrub/trace.h"
/* Set us up to scrub parents. */
int
xchk_setup_parent(
struct xfs_scrub *sc)
{
+ int error;
+
+ if (xchk_could_repair(sc)) {
+ error = xrep_setup_parent(sc);
+ if (error)
+ return error;
+ }
+
return xchk_setup_inode_contents(sc, 0);
}
@@ -143,7 +161,8 @@ xchk_parent_validate(
}
if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0, &error))
return error;
- if (dp == sc->ip || !S_ISDIR(VFS_I(dp)->i_mode)) {
+ if (dp == sc->ip || xrep_is_tempfile(dp) ||
+ !S_ISDIR(VFS_I(dp)->i_mode)) {
xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
goto out_rele;
}
@@ -185,6 +204,621 @@ out_rele:
return error;
}
+/*
+ * Checking of Parent Pointers
+ * ===========================
+ *
+ * On filesystems with directory parent pointers, we check the referential
+ * integrity by visiting each parent pointer of a child file and checking that
+ * the directory referenced by the pointer actually has a dirent pointing
+ * forward to the child file.
+ */
+
+/* Deferred parent pointer entry that we saved for later. */
+struct xchk_pptr {
+ /* Cookie for retrieval of the pptr name. */
+ xfblob_cookie name_cookie;
+
+ /* Parent pointer record. */
+ struct xfs_parent_rec pptr_rec;
+
+ /* Length of the pptr name. */
+ uint8_t namelen;
+};
+
+struct xchk_pptrs {
+ struct xfs_scrub *sc;
+
+ /* How many parent pointers did we find at the end? */
+ unsigned long long pptrs_found;
+
+ /* Parent of this directory. */
+ xfs_ino_t parent_ino;
+
+ /* Fixed-size array of xchk_pptr structures. */
+ struct xfarray *pptr_entries;
+
+ /* Blobs containing parent pointer names. */
+ struct xfblob *pptr_names;
+
+ /* Scratch buffer for scanning pptr xattrs */
+ struct xfs_da_args pptr_args;
+
+ /* If we've cycled the ILOCK, we must revalidate all deferred pptrs. */
+ bool need_revalidate;
+
+ /* Name buffer */
+ struct xfs_name xname;
+ char namebuf[MAXNAMELEN];
+};
+
+/* Does this parent pointer match the dotdot entry? */
+STATIC int
+xchk_parent_scan_dotdot(
+ struct xfs_scrub *sc,
+ struct xfs_inode *ip,
+ unsigned int attr_flags,
+ const unsigned char *name,
+ unsigned int namelen,
+ const void *value,
+ unsigned int valuelen,
+ void *priv)
+{
+ struct xchk_pptrs *pp = priv;
+ xfs_ino_t parent_ino;
+ int error;
+
+ if (!(attr_flags & XFS_ATTR_PARENT))
+ return 0;
+
+ error = xfs_parent_from_attr(sc->mp, attr_flags, name, namelen, value,
+ valuelen, &parent_ino, NULL);
+ if (error)
+ return error;
+
+ if (pp->parent_ino == parent_ino)
+ return -ECANCELED;
+
+ return 0;
+}
+
+/* Look up the dotdot entry so that we can check it as we walk the pptrs. */
+STATIC int
+xchk_parent_pptr_and_dotdot(
+ struct xchk_pptrs *pp)
+{
+ struct xfs_scrub *sc = pp->sc;
+ int error;
+
+ /* Look up '..' */
+ error = xchk_dir_lookup(sc, sc->ip, &xfs_name_dotdot, &pp->parent_ino);
+ if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
+ return error;
+ if (!xfs_verify_dir_ino(sc->mp, pp->parent_ino)) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
+ return 0;
+ }
+
+ /* Is this the root dir? Then '..' must point to itself. */
+ if (sc->ip == sc->mp->m_rootip) {
+ if (sc->ip->i_ino != pp->parent_ino)
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
+ return 0;
+ }
+
+ /*
+ * If this is now an unlinked directory, the dotdot value is
+ * meaningless as long as it points to a valid inode.
+ */
+ if (VFS_I(sc->ip)->i_nlink == 0)
+ return 0;
+
+ if (pp->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ return 0;
+
+ /* Otherwise, walk the pptrs again, and check. */
+ error = xchk_xattr_walk(sc, sc->ip, xchk_parent_scan_dotdot, NULL, pp);
+ if (error == -ECANCELED) {
+ /* Found a parent pointer that matches dotdot. */
+ return 0;
+ }
+ if (!error || error == -EFSCORRUPTED) {
+ /* Found a broken parent pointer or no match. */
+ xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ return 0;
+ }
+ return error;
+}
+
+/*
+ * Try to lock a parent directory for checking dirents. Returns the inode
+ * flags for the locks we now hold, or zero if we failed.
+ */
+STATIC unsigned int
+xchk_parent_lock_dir(
+ struct xfs_scrub *sc,
+ struct xfs_inode *dp)
+{
+ if (!xfs_ilock_nowait(dp, XFS_IOLOCK_SHARED))
+ return 0;
+
+ if (!xfs_ilock_nowait(dp, XFS_ILOCK_SHARED)) {
+ xfs_iunlock(dp, XFS_IOLOCK_SHARED);
+ return 0;
+ }
+
+ if (!xfs_need_iread_extents(&dp->i_df))
+ return XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED;
+
+ xfs_iunlock(dp, XFS_ILOCK_SHARED);
+
+ if (!xfs_ilock_nowait(dp, XFS_ILOCK_EXCL)) {
+ xfs_iunlock(dp, XFS_IOLOCK_SHARED);
+ return 0;
+ }
+
+ return XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL;
+}
+
+/* Check the forward link (dirent) associated with this parent pointer. */
+STATIC int
+xchk_parent_dirent(
+ struct xchk_pptrs *pp,
+ const struct xfs_name *xname,
+ struct xfs_inode *dp)
+{
+ struct xfs_scrub *sc = pp->sc;
+ xfs_ino_t child_ino;
+ int error;
+
+ /*
+ * Use the name attached to this parent pointer to look up the
+ * directory entry in the alleged parent.
+ */
+ error = xchk_dir_lookup(sc, dp, xname, &child_ino);
+ if (error == -ENOENT) {
+ xchk_fblock_xref_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ return 0;
+ }
+ if (!xchk_fblock_xref_process_error(sc, XFS_ATTR_FORK, 0, &error))
+ return error;
+
+ /* Does the inode number match? */
+ if (child_ino != sc->ip->i_ino) {
+ xchk_fblock_xref_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ return 0;
+ }
+
+ return 0;
+}
+
+/* Try to grab a parent directory. */
+STATIC int
+xchk_parent_iget(
+ struct xchk_pptrs *pp,
+ const struct xfs_parent_rec *pptr,
+ struct xfs_inode **dpp)
+{
+ struct xfs_scrub *sc = pp->sc;
+ struct xfs_inode *ip;
+ xfs_ino_t parent_ino = be64_to_cpu(pptr->p_ino);
+ int error;
+
+ /* Validate inode number. */
+ error = xfs_dir_ino_validate(sc->mp, parent_ino);
+ if (error) {
+ xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ return -ECANCELED;
+ }
+
+ error = xchk_iget(sc, parent_ino, &ip);
+ if (error == -EINVAL || error == -ENOENT) {
+ xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ return -ECANCELED;
+ }
+ if (!xchk_fblock_xref_process_error(sc, XFS_ATTR_FORK, 0, &error))
+ return error;
+
+ /* The parent must be a directory. */
+ if (!S_ISDIR(VFS_I(ip)->i_mode)) {
+ xchk_fblock_xref_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ goto out_rele;
+ }
+
+ /* Validate generation number. */
+ if (VFS_I(ip)->i_generation != be32_to_cpu(pptr->p_gen)) {
+ xchk_fblock_xref_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ goto out_rele;
+ }
+
+ *dpp = ip;
+ return 0;
+out_rele:
+ xchk_irele(sc, ip);
+ return 0;
+}
+
+/*
+ * Walk an xattr of a file. If this xattr is a parent pointer, follow it up
+ * to a parent directory and check that the parent has a dirent pointing back
+ * to us.
+ */
+STATIC int
+xchk_parent_scan_attr(
+ struct xfs_scrub *sc,
+ struct xfs_inode *ip,
+ unsigned int attr_flags,
+ const unsigned char *name,
+ unsigned int namelen,
+ const void *value,
+ unsigned int valuelen,
+ void *priv)
+{
+ struct xfs_name xname = {
+ .name = name,
+ .len = namelen,
+ };
+ struct xchk_pptrs *pp = priv;
+ struct xfs_inode *dp = NULL;
+ const struct xfs_parent_rec *pptr_rec = value;
+ xfs_ino_t parent_ino;
+ unsigned int lockmode;
+ int error;
+
+ if (!(attr_flags & XFS_ATTR_PARENT))
+ return 0;
+
+ error = xfs_parent_from_attr(sc->mp, attr_flags, name, namelen, value,
+ valuelen, &parent_ino, NULL);
+ if (error) {
+ xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ return error;
+ }
+
+ /* No self-referential parent pointers. */
+ if (parent_ino == sc->ip->i_ino) {
+ xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ return -ECANCELED;
+ }
+
+ pp->pptrs_found++;
+
+ error = xchk_parent_iget(pp, pptr_rec, &dp);
+ if (error)
+ return error;
+ if (!dp)
+ return 0;
+
+ /* Try to lock the inode. */
+ lockmode = xchk_parent_lock_dir(sc, dp);
+ if (!lockmode) {
+ struct xchk_pptr save_pp = {
+ .pptr_rec = *pptr_rec, /* struct copy */
+ .namelen = namelen,
+ };
+
+ /* Couldn't lock the inode, so save the pptr for later. */
+ trace_xchk_parent_defer(sc->ip, &xname, dp->i_ino);
+
+ error = xfblob_storename(pp->pptr_names, &save_pp.name_cookie,
+ &xname);
+ if (!xchk_fblock_xref_process_error(sc, XFS_ATTR_FORK, 0,
+ &error))
+ goto out_rele;
+
+ error = xfarray_append(pp->pptr_entries, &save_pp);
+ if (!xchk_fblock_xref_process_error(sc, XFS_ATTR_FORK, 0,
+ &error))
+ goto out_rele;
+
+ goto out_rele;
+ }
+
+ error = xchk_parent_dirent(pp, &xname, dp);
+ if (error)
+ goto out_unlock;
+
+out_unlock:
+ xfs_iunlock(dp, lockmode);
+out_rele:
+ xchk_irele(sc, dp);
+ return error;
+}
+
+/*
+ * Revalidate a parent pointer that we collected in the past but couldn't check
+ * because of lock contention. Returns 0 if the parent pointer is still valid,
+ * -ENOENT if it has gone away on us, or a negative errno.
+ */
+STATIC int
+xchk_parent_revalidate_pptr(
+ struct xchk_pptrs *pp,
+ const struct xfs_name *xname,
+ struct xfs_parent_rec *pptr)
+{
+ struct xfs_scrub *sc = pp->sc;
+ int error;
+
+ error = xfs_parent_lookup(sc->tp, sc->ip, xname, pptr, &pp->pptr_args);
+ if (error == -ENOATTR) {
+ /* Parent pointer went away, nothing to revalidate. */
+ return -ENOENT;
+ }
+
+ return error;
+}
+
+/*
+ * Check a parent pointer the slow way, which means we cycle locks a bunch
+ * and put up with revalidation until we get it done.
+ */
+STATIC int
+xchk_parent_slow_pptr(
+ struct xchk_pptrs *pp,
+ const struct xfs_name *xname,
+ struct xfs_parent_rec *pptr)
+{
+ struct xfs_scrub *sc = pp->sc;
+ struct xfs_inode *dp = NULL;
+ unsigned int lockmode;
+ int error;
+
+ /* Check that the deferred parent pointer still exists. */
+ if (pp->need_revalidate) {
+ error = xchk_parent_revalidate_pptr(pp, xname, pptr);
+ if (error == -ENOENT)
+ return 0;
+ if (!xchk_fblock_xref_process_error(sc, XFS_ATTR_FORK, 0,
+ &error))
+ return error;
+ }
+
+ error = xchk_parent_iget(pp, pptr, &dp);
+ if (error)
+ return error;
+ if (!dp)
+ return 0;
+
+ /*
+ * If we can grab both IOLOCK and ILOCK of the alleged parent, we
+ * can proceed with the validation.
+ */
+ lockmode = xchk_parent_lock_dir(sc, dp);
+ if (lockmode) {
+ trace_xchk_parent_slowpath(sc->ip, xname, dp->i_ino);
+ goto check_dirent;
+ }
+
+ /*
+ * We couldn't lock the parent dir. Drop all the locks and try to
+ * get them again, one at a time.
+ */
+ xchk_iunlock(sc, sc->ilock_flags);
+ pp->need_revalidate = true;
+
+ trace_xchk_parent_ultraslowpath(sc->ip, xname, dp->i_ino);
+
+ error = xchk_dir_trylock_for_pptrs(sc, dp, &lockmode);
+ if (error)
+ goto out_rele;
+
+ /* Revalidate the parent pointer now that we cycled locks. */
+ error = xchk_parent_revalidate_pptr(pp, xname, pptr);
+ if (error == -ENOENT) {
+ error = 0;
+ goto out_unlock;
+ }
+ if (!xchk_fblock_xref_process_error(sc, XFS_ATTR_FORK, 0, &error))
+ goto out_unlock;
+
+check_dirent:
+ error = xchk_parent_dirent(pp, xname, dp);
+out_unlock:
+ xfs_iunlock(dp, lockmode);
+out_rele:
+ xchk_irele(sc, dp);
+ return error;
+}
+
+/* Check all the parent pointers that we deferred the first time around. */
+STATIC int
+xchk_parent_finish_slow_pptrs(
+ struct xchk_pptrs *pp)
+{
+ xfarray_idx_t array_cur;
+ int error;
+
+ foreach_xfarray_idx(pp->pptr_entries, array_cur) {
+ struct xchk_pptr pptr;
+
+ if (pp->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ return 0;
+
+ error = xfarray_load(pp->pptr_entries, array_cur, &pptr);
+ if (error)
+ return error;
+
+ error = xfblob_loadname(pp->pptr_names, pptr.name_cookie,
+ &pp->xname, pptr.namelen);
+ if (error)
+ return error;
+
+ error = xchk_parent_slow_pptr(pp, &pp->xname, &pptr.pptr_rec);
+ if (error)
+ return error;
+ }
+
+ /* Empty out both xfiles now that we've checked everything. */
+ xfarray_truncate(pp->pptr_entries);
+ xfblob_truncate(pp->pptr_names);
+ return 0;
+}
+
+/* Count the number of parent pointers. */
+STATIC int
+xchk_parent_count_pptr(
+ struct xfs_scrub *sc,
+ struct xfs_inode *ip,
+ unsigned int attr_flags,
+ const unsigned char *name,
+ unsigned int namelen,
+ const void *value,
+ unsigned int valuelen,
+ void *priv)
+{
+ struct xchk_pptrs *pp = priv;
+ int error;
+
+ if (!(attr_flags & XFS_ATTR_PARENT))
+ return 0;
+
+ error = xfs_parent_from_attr(sc->mp, attr_flags, name, namelen, value,
+ valuelen, NULL, NULL);
+ if (error)
+ return error;
+
+ pp->pptrs_found++;
+ return 0;
+}
+
+/*
+ * Compare the number of parent pointers to the link count. For
+ * non-directories these should be the same. For unlinked directories the
+ * count should be zero; for linked directories, it should be nonzero.
+ */
+STATIC int
+xchk_parent_count_pptrs(
+ struct xchk_pptrs *pp)
+{
+ struct xfs_scrub *sc = pp->sc;
+ int error;
+
+ /*
+ * If we cycled the ILOCK while cross-checking parent pointers with
+ * dirents, then we need to recalculate the number of parent pointers.
+ */
+ if (pp->need_revalidate) {
+ pp->pptrs_found = 0;
+ error = xchk_xattr_walk(sc, sc->ip, xchk_parent_count_pptr,
+ NULL, pp);
+ if (error == -EFSCORRUPTED) {
+ /* Found a bad parent pointer */
+ xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
+ return 0;
+ }
+ if (error)
+ return error;
+ }
+
+ if (S_ISDIR(VFS_I(sc->ip)->i_mode)) {
+ if (sc->ip == sc->mp->m_rootip)
+ pp->pptrs_found++;
+
+ if (VFS_I(sc->ip)->i_nlink == 0 && pp->pptrs_found > 0)
+ xchk_ino_set_corrupt(sc, sc->ip->i_ino);
+ else if (VFS_I(sc->ip)->i_nlink > 0 &&
+ pp->pptrs_found == 0)
+ xchk_ino_set_corrupt(sc, sc->ip->i_ino);
+ } else {
+ if (VFS_I(sc->ip)->i_nlink != pp->pptrs_found)
+ xchk_ino_set_corrupt(sc, sc->ip->i_ino);
+ }
+
+ return 0;
+}
+
+/* Check parent pointers of a file. */
+STATIC int
+xchk_parent_pptr(
+ struct xfs_scrub *sc)
+{
+ struct xchk_pptrs *pp;
+ char *descr;
+ int error;
+
+ pp = kvzalloc(sizeof(struct xchk_pptrs), XCHK_GFP_FLAGS);
+ if (!pp)
+ return -ENOMEM;
+ pp->sc = sc;
+ pp->xname.name = pp->namebuf;
+
+ /*
+ * Set up some staging memory for parent pointers that we can't check
+ * due to locking contention.
+ */
+ descr = xchk_xfile_ino_descr(sc, "slow parent pointer entries");
+ error = xfarray_create(descr, 0, sizeof(struct xchk_pptr),
+ &pp->pptr_entries);
+ kfree(descr);
+ if (error)
+ goto out_pp;
+
+ descr = xchk_xfile_ino_descr(sc, "slow parent pointer names");
+ error = xfblob_create(descr, &pp->pptr_names);
+ kfree(descr);
+ if (error)
+ goto out_entries;
+
+ error = xchk_xattr_walk(sc, sc->ip, xchk_parent_scan_attr, NULL, pp);
+ if (error == -ECANCELED) {
+ error = 0;
+ goto out_names;
+ }
+ if (error)
+ goto out_names;
+
+ error = xchk_parent_finish_slow_pptrs(pp);
+ if (error == -ETIMEDOUT) {
+ /* Couldn't grab a lock, scrub was marked incomplete */
+ error = 0;
+ goto out_names;
+ }
+ if (error)
+ goto out_names;
+
+ if (pp->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out_names;
+
+ /*
+ * For subdirectories, make sure the dotdot entry references the same
+ * inode as the parent pointers.
+ *
+ * If we're scanning a /consistent/ directory, there should only be
+ * one parent pointer, and it should point to the same directory as
+ * the dotdot entry.
+ *
+ * However, a corrupt directory tree might feature a subdirectory with
+ * multiple parents. The directory loop scanner is responsible for
+ * correcting that kind of problem, so for now we only validate that
+ * the dotdot entry matches /one/ of the parents.
+ */
+ if (S_ISDIR(VFS_I(sc->ip)->i_mode)) {
+ error = xchk_parent_pptr_and_dotdot(pp);
+ if (error)
+ goto out_names;
+ }
+
+ if (pp->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out_pp;
+
+ /*
+ * Complain if the number of parent pointers doesn't match the link
+ * count. This could be a sign of missing parent pointers (or an
+ * incorrect link count).
+ */
+ error = xchk_parent_count_pptrs(pp);
+ if (error)
+ goto out_names;
+
+out_names:
+ xfblob_destroy(pp->pptr_names);
+out_entries:
+ xfarray_destroy(pp->pptr_entries);
+out_pp:
+ kvfree(pp);
+ return error;
+}
+
/* Scrub a parent pointer. */
int
xchk_parent(
@@ -194,6 +828,9 @@ xchk_parent(
xfs_ino_t parent_ino;
int error = 0;
+ if (xfs_has_parent(mp))
+ return xchk_parent_pptr(sc);
+
/*
* If we're a directory, check that the '..' link points up to
* a directory that has one entry pointing to us.
@@ -237,3 +874,64 @@ xchk_parent(
return error;
}
+
+/*
+ * Decide if this file's extended attributes (and therefore its parent
+ * pointers) have been zapped to satisfy the inode and ifork verifiers.
+ * Checking and repairing should be postponed until the extended attribute
+ * structure is fixed.
+ */
+bool
+xchk_pptr_looks_zapped(
+ struct xfs_inode *ip)
+{
+ struct xfs_mount *mp = ip->i_mount;
+ struct inode *inode = VFS_I(ip);
+
+ ASSERT(xfs_has_parent(mp));
+
+ /*
+ * Temporary files that cannot be linked into the directory tree do not
+ * have attr forks because they cannot ever have parents.
+ */
+ if (inode->i_nlink == 0 && !(inode->i_state & I_LINKABLE))
+ return false;
+
+ /*
+ * Directory tree roots do not have parents, so the expected outcome
+ * of a parent pointer scan is always the empty set. It's safe to scan
+ * them even if the attr fork was zapped.
+ */
+ if (ip == mp->m_rootip)
+ return false;
+
+ /*
+ * Metadata inodes are all rooted in the superblock and do not have
+ * any parents. Hence the attr fork will not be initialized, but
+ * there are no parent pointers that might have been zapped.
+ */
+ if (xfs_is_metadata_inode(ip))
+ return false;
+
+ /*
+ * Linked and linkable non-rootdir files should always have an
+ * attribute fork because that is where parent pointers are
+ * stored. If the fork is absent, something is amiss.
+ */
+ if (!xfs_inode_has_attr_fork(ip))
+ return true;
+
+ /* Repair zapped this file's attr fork a short time ago */
+ if (xfs_ifork_zapped(ip, XFS_ATTR_FORK))
+ return true;
+
+ /*
+ * If the dinode repair found a bad attr fork, it will reset the fork
+ * to extents format with zero records and wait for the bmapbta
+ * scrubber to reconstruct the block mappings. The extended attribute
+ * structure always contain some content when parent pointers are
+ * enabled, so this is a clear sign of a zapped attr fork.
+ */
+ return ip->i_af.if_format == XFS_DINODE_FMT_EXTENTS &&
+ ip->i_af.if_nextents == 0;
+}