1 files changed, 363 insertions, 14 deletions

diff --git a/fs/xfs/scrub/dir.c b/fs/xfs/scrub/dir.c
index 076a310b8eb0..bf9199e8df63 100644
--- a/fs/xfs/scrub/dir.c
+++ b/fs/xfs/scrub/dir.c
@@ -16,22 +16,70 @@
 #include "xfs_dir2.h"
 #include "xfs_dir2_priv.h"
 #include "xfs_health.h"
+#include "xfs_attr.h"
+#include "xfs_parent.h"
 #include "scrub/scrub.h"
 #include "scrub/common.h"
 #include "scrub/dabtree.h"
 #include "scrub/readdir.h"
 #include "scrub/health.h"
+#include "scrub/repair.h"
+#include "scrub/trace.h"
+#include "scrub/xfile.h"
+#include "scrub/xfarray.h"
+#include "scrub/xfblob.h"
 
 /* Set us up to scrub directories. */
 int
 xchk_setup_directory(
 	struct xfs_scrub	*sc)
 {
+	int			error;
+
+	if (xchk_could_repair(sc)) {
+		error = xrep_setup_directory(sc);
+		if (error)
+			return error;
+	}
+
 	return xchk_setup_inode_contents(sc, 0);
 }
 
 /* Directories */
 
+/* Deferred directory entry that we saved for later. */
+struct xchk_dirent {
+	/* Cookie for retrieval of the dirent name. */
+	xfblob_cookie		name_cookie;
+
+	/* Child inode number. */
+	xfs_ino_t		ino;
+
+	/* Length of the pptr name. */
+	uint8_t			namelen;
+};
+
+struct xchk_dir {
+	struct xfs_scrub	*sc;
+
+	/* information for parent pointer validation. */
+	struct xfs_parent_rec	pptr_rec;
+	struct xfs_da_args	pptr_args;
+
+	/* Fixed-size array of xchk_dirent structures. */
+	struct xfarray		*dir_entries;
+
+	/* Blobs containing dirent names. */
+	struct xfblob		*dir_names;
+
+	/* If we've cycled the ILOCK, we must revalidate deferred dirents. */
+	bool			need_revalidate;
+
+	/* Name buffer for dirent revalidation. */
+	struct xfs_name		xname;
+	uint8_t			namebuf[MAXNAMELEN];
+};
+
 /* Scrub a directory entry. */
 
 /* Check that an inode's mode matches a given XFS_DIR3_FT_* type. */
@@ -55,6 +103,108 @@ xchk_dir_check_ftype(
 }
 
 /*
+ * Try to lock a child file for checking parent pointers.  Returns the inode
+ * flags for the locks we now hold, or zero if we failed.
+ */
+STATIC unsigned int
+xchk_dir_lock_child(
+	struct xfs_scrub	*sc,
+	struct xfs_inode	*ip)
+{
+	if (!xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED))
+		return 0;
+
+	if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
+		xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+		return 0;
+	}
+
+	if (!xfs_inode_has_attr_fork(ip) || !xfs_need_iread_extents(&ip->i_af))
+		return XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED;
+
+	xfs_iunlock(ip, XFS_ILOCK_SHARED);
+
+	if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
+		xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+		return 0;
+	}
+
+	return XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL;
+}
+
+/* Check the backwards link (parent pointer) associated with this dirent. */
+STATIC int
+xchk_dir_parent_pointer(
+	struct xchk_dir		*sd,
+	const struct xfs_name	*name,
+	struct xfs_inode	*ip)
+{
+	struct xfs_scrub	*sc = sd->sc;
+	int			error;
+
+	xfs_inode_to_parent_rec(&sd->pptr_rec, sc->ip);
+	error = xfs_parent_lookup(sc->tp, ip, name, &sd->pptr_rec,
+			&sd->pptr_args);
+	if (error == -ENOATTR)
+		xchk_fblock_xref_set_corrupt(sc, XFS_DATA_FORK, 0);
+
+	return 0;
+}
+
+/* Look for a parent pointer matching this dirent, if the child isn't busy. */
+STATIC int
+xchk_dir_check_pptr_fast(
+	struct xchk_dir		*sd,
+	xfs_dir2_dataptr_t	dapos,
+	const struct xfs_name	*name,
+	struct xfs_inode	*ip)
+{
+	struct xfs_scrub	*sc = sd->sc;
+	unsigned int		lockmode;
+	int			error;
+
+	/* dot and dotdot entries do not have parent pointers */
+	if (xfs_dir2_samename(name, &xfs_name_dot) ||
+	    xfs_dir2_samename(name, &xfs_name_dotdot))
+		return 0;
+
+	/* No self-referential non-dot or dotdot dirents. */
+	if (ip == sc->ip) {
+		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
+		return -ECANCELED;
+	}
+
+	/* Try to lock the inode. */
+	lockmode = xchk_dir_lock_child(sc, ip);
+	if (!lockmode) {
+		struct xchk_dirent	save_de = {
+			.namelen	= name->len,
+			.ino		= ip->i_ino,
+		};
+
+		/* Couldn't lock the inode, so save the dirent for later. */
+		trace_xchk_dir_defer(sc->ip, name, ip->i_ino);
+
+		error = xfblob_storename(sd->dir_names, &save_de.name_cookie,
+				name);
+		if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0,
+					&error))
+			return error;
+
+		error = xfarray_append(sd->dir_entries, &save_de);
+		if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0,
+					&error))
+			return error;
+
+		return 0;
+	}
+
+	error = xchk_dir_parent_pointer(sd, name, ip);
+	xfs_iunlock(ip, lockmode);
+	return error;
+}
+
+/*
  * Scrub a single directory entry.
  *
  * Check the inode number to make sure it's sane, then we check that we can
@@ -71,6 +221,7 @@ xchk_dir_actor(
 {
 	struct xfs_mount	*mp = dp->i_mount;
 	struct xfs_inode	*ip;
+	struct xchk_dir		*sd = priv;
 	xfs_ino_t		lookup_ino;
 	xfs_dablk_t		offset;
 	int			error = 0;
@@ -137,6 +288,14 @@ xchk_dir_actor(
 		goto out;
 
 	xchk_dir_check_ftype(sc, offset, ip, name->type);
+
+	if (xfs_has_parent(mp)) {
+		error = xchk_dir_check_pptr_fast(sd, dapos, name, ip);
+		if (error)
+			goto out_rele;
+	}
+
+out_rele:
 	xchk_irele(sc, ip);
 out:
 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
@@ -196,8 +355,8 @@ xchk_dir_rec(
 		xchk_da_set_corrupt(ds, level);
 		goto out;
 	}
-	error = xfs_dir3_data_read(ds->dargs.trans, dp, rec_bno,
-			XFS_DABUF_MAP_HOLE_OK, &bp);
+	error = xfs_dir3_data_read(ds->dargs.trans, dp, ds->dargs.owner,
+			rec_bno, XFS_DABUF_MAP_HOLE_OK, &bp);
 	if (!xchk_fblock_process_error(ds->sc, XFS_DATA_FORK, rec_bno,
 			&error))
 		goto out;
@@ -315,10 +474,11 @@ xchk_directory_data_bestfree(
 		/* dir block format */
 		if (lblk != XFS_B_TO_FSBT(mp, XFS_DIR2_DATA_OFFSET))
 			xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
-		error = xfs_dir3_block_read(sc->tp, sc->ip, &bp);
+		error = xfs_dir3_block_read(sc->tp, sc->ip, sc->ip->i_ino, &bp);
 	} else {
 		/* dir data format */
-		error = xfs_dir3_data_read(sc->tp, sc->ip, lblk, 0, &bp);
+		error = xfs_dir3_data_read(sc->tp, sc->ip, sc->ip->i_ino, lblk,
+				0, &bp);
 	}
 	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 		goto out;
@@ -470,7 +630,7 @@ xchk_directory_leaf1_bestfree(
 	int				error;
 
 	/* Read the free space block. */
-	error = xfs_dir3_leaf_read(sc->tp, sc->ip, lblk, &bp);
+	error = xfs_dir3_leaf_read(sc->tp, sc->ip, sc->ip->i_ino, lblk, &bp);
 	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 		return error;
 	xchk_buffer_recheck(sc, bp);
@@ -531,10 +691,9 @@ xchk_directory_leaf1_bestfree(
 	/* Check all the bestfree entries. */
 	for (i = 0; i < bestcount; i++, bestp++) {
 		best = be16_to_cpu(*bestp);
-		error = xfs_dir3_data_read(sc->tp, sc->ip,
+		error = xfs_dir3_data_read(sc->tp, sc->ip, args->owner,
 				xfs_dir2_db_to_da(args->geo, i),
-				XFS_DABUF_MAP_HOLE_OK,
-				&dbp);
+				XFS_DABUF_MAP_HOLE_OK, &dbp);
 		if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk,
 				&error))
 			break;
@@ -577,7 +736,7 @@ xchk_directory_free_bestfree(
 	int				error;
 
 	/* Read the free space block */
-	error = xfs_dir2_free_read(sc->tp, sc->ip, lblk, &bp);
+	error = xfs_dir2_free_read(sc->tp, sc->ip, sc->ip->i_ino, lblk, &bp);
 	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 		return error;
 	xchk_buffer_recheck(sc, bp);
@@ -597,7 +756,7 @@ xchk_directory_free_bestfree(
 			stale++;
 			continue;
 		}
-		error = xfs_dir3_data_read(sc->tp, sc->ip,
+		error = xfs_dir3_data_read(sc->tp, sc->ip, args->owner,
 				(freehdr.firstdb + i) * args->geo->fsbcount,
 				0, &dbp);
 		if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk,
@@ -621,10 +780,11 @@ xchk_directory_blocks(
 {
 	struct xfs_bmbt_irec	got;
 	struct xfs_da_args	args = {
-		.dp		= sc ->ip,
+		.dp		= sc->ip,
 		.whichfork	= XFS_DATA_FORK,
 		.geo		= sc->mp->m_dir_geo,
 		.trans		= sc->tp,
+		.owner		= sc->ip->i_ino,
 	};
 	struct xfs_ifork	*ifp = xfs_ifork_ptr(sc->ip, XFS_DATA_FORK);
 	struct xfs_mount	*mp = sc->mp;
@@ -648,7 +808,8 @@ xchk_directory_blocks(
 	free_lblk = XFS_B_TO_FSB(mp, XFS_DIR2_FREE_OFFSET);
 
 	/* Is this a block dir? */
-	error = xfs_dir2_isblock(&args, &is_block);
+	if (xfs_dir2_format(&args, &error) == XFS_DIR2_FMT_BLOCK)
+		is_block = true;
 	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 		goto out;
 
@@ -752,11 +913,148 @@ out:
 	return error;
 }
 
+/*
+ * Revalidate a dirent that we collected in the past but couldn't check because
+ * of lock contention.  Returns 0 if the dirent is still valid, -ENOENT if it
+ * has gone away on us, or a negative errno.
+ */
+STATIC int
+xchk_dir_revalidate_dirent(
+	struct xchk_dir		*sd,
+	const struct xfs_name	*xname,
+	xfs_ino_t		ino)
+{
+	struct xfs_scrub	*sc = sd->sc;
+	xfs_ino_t		child_ino;
+	int			error;
+
+	/*
+	 * Look up the directory entry.  If we get -ENOENT, the directory entry
+	 * went away and there's nothing to revalidate.  Return any other
+	 * error.
+	 */
+	error = xchk_dir_lookup(sc, sc->ip, xname, &child_ino);
+	if (error)
+		return error;
+
+	/* The inode number changed, nothing to revalidate. */
+	if (ino != child_ino)
+		return -ENOENT;
+
+	return 0;
+}
+
+/*
+ * Check a directory entry's parent pointers the slow way, which means we cycle
+ * locks a bunch and put up with revalidation until we get it done.
+ */
+STATIC int
+xchk_dir_slow_dirent(
+	struct xchk_dir		*sd,
+	struct xchk_dirent	*dirent,
+	const struct xfs_name	*xname)
+{
+	struct xfs_scrub	*sc = sd->sc;
+	struct xfs_inode	*ip;
+	unsigned int		lockmode;
+	int			error;
+
+	/* Check that the deferred dirent still exists. */
+	if (sd->need_revalidate) {
+		error = xchk_dir_revalidate_dirent(sd, xname, dirent->ino);
+		if (error == -ENOENT)
+			return 0;
+		if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0,
+					&error))
+			return error;
+	}
+
+	error = xchk_iget(sc, dirent->ino, &ip);
+	if (error == -EINVAL || error == -ENOENT) {
+		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
+		return 0;
+	}
+	if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0, &error))
+		return error;
+
+	/*
+	 * If we can grab both IOLOCK and ILOCK of the alleged child, we can
+	 * proceed with the validation.
+	 */
+	lockmode = xchk_dir_lock_child(sc, ip);
+	if (lockmode) {
+		trace_xchk_dir_slowpath(sc->ip, xname, ip->i_ino);
+		goto check_pptr;
+	}
+
+	/*
+	 * We couldn't lock the child file.  Drop all the locks and try to
+	 * get them again, one at a time.
+	 */
+	xchk_iunlock(sc, sc->ilock_flags);
+	sd->need_revalidate = true;
+
+	trace_xchk_dir_ultraslowpath(sc->ip, xname, ip->i_ino);
+
+	error = xchk_dir_trylock_for_pptrs(sc, ip, &lockmode);
+	if (error)
+		goto out_rele;
+
+	/* Revalidate, since we just cycled the locks. */
+	error = xchk_dir_revalidate_dirent(sd, xname, dirent->ino);
+	if (error == -ENOENT) {
+		error = 0;
+		goto out_unlock;
+	}
+	if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0, &error))
+		goto out_unlock;
+
+check_pptr:
+	error = xchk_dir_parent_pointer(sd, xname, ip);
+out_unlock:
+	xfs_iunlock(ip, lockmode);
+out_rele:
+	xchk_irele(sc, ip);
+	return error;
+}
+
+/* Check all the dirents that we deferred the first time around. */
+STATIC int
+xchk_dir_finish_slow_dirents(
+	struct xchk_dir		*sd)
+{
+	xfarray_idx_t		array_cur;
+	int			error;
+
+	foreach_xfarray_idx(sd->dir_entries, array_cur) {
+		struct xchk_dirent	dirent;
+
+		if (sd->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+			return 0;
+
+		error = xfarray_load(sd->dir_entries, array_cur, &dirent);
+		if (error)
+			return error;
+
+		error = xfblob_loadname(sd->dir_names, dirent.name_cookie,
+				&sd->xname, dirent.namelen);
+		if (error)
+			return error;
+
+		error = xchk_dir_slow_dirent(sd, &dirent, &sd->xname);
+		if (error)
+			return error;
+	}
+
+	return 0;
+}
+
 /* Scrub a whole directory. */
 int
 xchk_directory(
 	struct xfs_scrub	*sc)
 {
+	struct xchk_dir		*sd;
 	int			error;
 
 	if (!S_ISDIR(VFS_I(sc->ip)->i_mode))
@@ -789,9 +1087,60 @@ xchk_directory(
 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 		return 0;
 
+	sd = kvzalloc(sizeof(struct xchk_dir), XCHK_GFP_FLAGS);
+	if (!sd)
+		return -ENOMEM;
+	sd->sc = sc;
+	sd->xname.name = sd->namebuf;
+
+	if (xfs_has_parent(sc->mp)) {
+		char		*descr;
+
+		/*
+		 * Set up some staging memory for dirents that we can't check
+		 * due to locking contention.
+		 */
+		descr = xchk_xfile_ino_descr(sc, "slow directory entries");
+		error = xfarray_create(descr, 0, sizeof(struct xchk_dirent),
+				&sd->dir_entries);
+		kfree(descr);
+		if (error)
+			goto out_sd;
+
+		descr = xchk_xfile_ino_descr(sc, "slow directory entry names");
+		error = xfblob_create(descr, &sd->dir_names);
+		kfree(descr);
+		if (error)
+			goto out_entries;
+	}
+
 	/* Look up every name in this directory by hash. */
-	error = xchk_dir_walk(sc, sc->ip, xchk_dir_actor, NULL);
-	if (error && error != -ECANCELED)
+	error = xchk_dir_walk(sc, sc->ip, xchk_dir_actor, sd);
+	if (error == -ECANCELED)
+		error = 0;
+	if (error)
+		goto out_names;
+
+	if (xfs_has_parent(sc->mp)) {
+		error = xchk_dir_finish_slow_dirents(sd);
+		if (error == -ETIMEDOUT) {
+			/* Couldn't grab a lock, scrub was marked incomplete */
+			error = 0;
+			goto out_names;
+		}
+		if (error)
+			goto out_names;
+	}
+
+out_names:
+	if (sd->dir_names)
+		xfblob_destroy(sd->dir_names);
+out_entries:
+	if (sd->dir_entries)
+		xfarray_destroy(sd->dir_entries);
+out_sd:
+	kvfree(sd);
+	if (error)
 		return error;
 
 	/* If the dir is clean, it is clearly not zapped. */