xfs: hoist xfs_iunlink to libxfs

Move xfs_iunlink and xfs_iunlink_remove to libxfs.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

4 files changed, 431 insertions, 421 deletions

diff --git a/fs/xfs/libxfs/xfs_inode_util.c b/fs/xfs/libxfs/xfs_inode_util.c
index c6e8187af113..e6fd0455c994 100644
--- a/fs/xfs/libxfs/xfs_inode_util.c
+++ b/fs/xfs/libxfs/xfs_inode_util.c
@@ -18,6 +18,9 @@
 #include "xfs_ialloc.h"
 #include "xfs_health.h"
 #include "xfs_bmap.h"
+#include "xfs_error.h"
+#include "xfs_trace.h"
+#include "xfs_ag.h"
 
 uint16_t
 xfs_flags2diflags(
@@ -342,3 +345,414 @@ xfs_inode_init(
 	/* now that we have an i_mode we can setup the inode structure */
 	xfs_setup_inode(ip);
 }
+
+/*
+ * 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(tp->t_mountp, pag->pag_agno, 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;
+}
+
+/* Set an on-disk inode's next_unlinked pointer. */
+STATIC void
+xfs_iunlink_update_dinode(
+	struct xfs_trans	*tp,
+	struct xfs_perag	*pag,
+	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, pag->pag_agno, next_agino));
+
+	trace_xfs_iunlink_update_dinode(mp, pag->pag_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);
+}
+
+/* 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,
+	struct xfs_perag	*pag,
+	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, pag->pag_agno, next_agino));
+
+	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &ibp);
+	if (error)
+		return error;
+	dip = xfs_buf_offset(ibp, ip->i_imap.im_boffset);
+
+	/* Make sure the old pointer isn't garbage. */
+	old_value = be32_to_cpu(dip->di_next_unlinked);
+	if (!xfs_verify_agino_or_null(mp, pag->pag_agno, old_value)) {
+		xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
+				sizeof(*dip), __this_address);
+		xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+		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);
+			xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
+			error = -EFSCORRUPTED;
+		}
+		goto out;
+	}
+
+	/* Ok, update the new pointer. */
+	xfs_iunlink_update_dinode(tp, pag, 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.
+ */
+int
+xfs_iunlink(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*ip)
+{
+	struct xfs_mount	*mp = tp->t_mountp;
+	struct xfs_perag	*pag;
+	struct xfs_agi		*agi;
+	struct xfs_buf		*agibp;
+	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;
+
+	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(mp, tp, pag->pag_agno, &agibp);
+	if (error)
+		goto out;
+	agi = agibp->b_addr;
+
+	/*
+	 * 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, pag->pag_agno, next_agino)) {
+		xfs_buf_mark_corrupt(agibp);
+		xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
+		error = -EFSCORRUPTED;
+		goto out;
+	}
+
+	if (next_agino != NULLAGINO) {
+		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, pag, next_agino,
+				&old_agino);
+		if (error)
+			goto out;
+		ASSERT(old_agino == NULLAGINO);
+
+		/*
+		 * agino has been unlinked, add a backref from the next inode
+		 * back to agino.
+		 */
+		error = xfs_iunlink_add_backref(pag, agino, next_agino);
+		if (error)
+			goto out;
+	}
+
+	/* Point the head of the list to point to this inode. */
+	error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino);
+out:
+	xfs_perag_put(pag);
+	return error;
+}
+
+/* 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, bpp);
+	if (error) {
+		xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
+				__func__, error);
+		return error;
+	}
+
+	*dipp = xfs_buf_offset(*bpp, imap->im_boffset);
+	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,
+	struct xfs_perag	*pag,
+	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_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, pag->pag_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, pag->pag_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, pag->pag_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, pag->pag_agno, unlinked_agino) ||
+		    next_agino == unlinked_agino) {
+			XFS_CORRUPTION_ERROR(__func__,
+					XFS_ERRLEVEL_LOW, mp,
+					*dipp, sizeof(**dipp));
+			xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
+			error = -EFSCORRUPTED;
+			return error;
+		}
+		next_agino = unlinked_agino;
+	}
+
+	return 0;
+}
+
+/*
+ * 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_mount	*mp = tp->t_mountp;
+	struct xfs_agi		*agi;
+	struct xfs_buf		*agibp;
+	struct xfs_buf		*last_ibp;
+	struct xfs_dinode	*last_dip = NULL;
+	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, pag->pag_agno, &agibp);
+	if (error)
+		return error;
+	agi = agibp->b_addr;
+
+	/*
+	 * 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, pag->pag_agno, 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_update_inode(tp, ip, pag, 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) {
+		error = xfs_iunlink_change_backref(pag, next_agino, NULLAGINO);
+		if (error)
+			return error;
+	}
+
+	if (head_agino != agino) {
+		struct xfs_imap	imap;
+		xfs_agino_t	prev_agino;
+
+		/* We need to search the list for the inode being freed. */
+		error = xfs_iunlink_map_prev(tp, pag, head_agino, agino,
+				&prev_agino, &imap, &last_dip, &last_ibp);
+		if (error)
+			return error;
+
+		/* Point the previous inode on the list to the next inode. */
+		xfs_iunlink_update_dinode(tp, pag, 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.
+		 */
+		return xfs_iunlink_change_backref(agibp->b_pag, agino,
+				next_agino);
+	}
+
+	/* Point the head of the list to the next unlinked inode. */
+	return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index,
+			next_agino);
+}
diff --git a/fs/xfs/libxfs/xfs_inode_util.h b/fs/xfs/libxfs/xfs_inode_util.h
index a38999109c53..a32912c2cc4d 100644
--- a/fs/xfs/libxfs/xfs_inode_util.h
+++ b/fs/xfs/libxfs/xfs_inode_util.h
@@ -55,9 +55,23 @@ void xfs_trans_ichgtime(struct xfs_trans *tp, struct xfs_inode *ip, int flags);
 void xfs_inode_init(struct xfs_trans *tp, const struct xfs_icreate_args *args,
 		struct xfs_inode *ip);
 
+int xfs_iunlink(struct xfs_trans *tp, struct xfs_inode *ip);
+int xfs_iunlink_remove(struct xfs_trans *tp, struct xfs_perag *pag,
+		struct xfs_inode *ip);
+
 /* The libxfs client must provide this group of helper functions. */
 
 /* Initialize the incore inode. */
 void xfs_setup_inode(struct xfs_inode *ip);
 
+/* Unlinked inode backref cache functions.  Optional. */
+int xfs_iunlink_init(struct xfs_perag *pag);
+void xfs_iunlink_destroy(struct xfs_perag *pag);
+xfs_agino_t xfs_iunlink_lookup_backref(struct xfs_perag *pag,
+		xfs_agino_t agino);
+int xfs_iunlink_add_backref(struct xfs_perag *pag, xfs_agino_t prev_agino,
+		xfs_agino_t this_agino);
+int xfs_iunlink_change_backref(struct xfs_perag *pag, xfs_agino_t prev_agino,
+		xfs_agino_t this_agino);
+
 #endif /* __XFS_INODE_UTIL_H__ */
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 0d38d35148d2..fe0538efb484 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -41,9 +41,6 @@
 
 kmem_zone_t *xfs_inode_zone;
 
-STATIC int xfs_iunlink_remove(struct xfs_trans *tp, struct xfs_perag *pag,
-	struct xfs_inode *);
-
 /*
  * 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
@@ -1686,7 +1683,7 @@ static const struct rhashtable_params xfs_iunlink_hash_params = {
  * Return X, where X.next_unlinked == @agino.  Returns NULLAGINO if no such
  * relation is found.
  */
-static xfs_agino_t
+xfs_agino_t
 xfs_iunlink_lookup_backref(
 	struct xfs_perag	*pag,
 	xfs_agino_t		agino)
@@ -1732,7 +1729,7 @@ xfs_iunlink_insert_backref(
 }
 
 /* Remember that @prev_agino.next_unlinked = @this_agino. */
-static int
+int
 xfs_iunlink_add_backref(
 	struct xfs_perag	*pag,
 	xfs_agino_t		prev_agino,
@@ -1755,7 +1752,7 @@ xfs_iunlink_add_backref(
  * 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
+int
 xfs_iunlink_change_backref(
 	struct xfs_perag	*pag,
 	xfs_agino_t		agino,
@@ -1829,417 +1826,6 @@ xfs_iunlink_destroy(
 }
 
 /*
- * 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(tp->t_mountp, pag->pag_agno, 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;
-}
-
-/* Set an on-disk inode's next_unlinked pointer. */
-STATIC void
-xfs_iunlink_update_dinode(
-	struct xfs_trans	*tp,
-	struct xfs_perag	*pag,
-	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, pag->pag_agno, next_agino));
-
-	trace_xfs_iunlink_update_dinode(mp, pag->pag_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);
-}
-
-/* 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,
-	struct xfs_perag	*pag,
-	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, pag->pag_agno, next_agino));
-
-	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &ibp);
-	if (error)
-		return error;
-	dip = xfs_buf_offset(ibp, ip->i_imap.im_boffset);
-
-	/* Make sure the old pointer isn't garbage. */
-	old_value = be32_to_cpu(dip->di_next_unlinked);
-	if (!xfs_verify_agino_or_null(mp, pag->pag_agno, old_value)) {
-		xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
-				sizeof(*dip), __this_address);
-		xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
-		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);
-			xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
-			error = -EFSCORRUPTED;
-		}
-		goto out;
-	}
-
-	/* Ok, update the new pointer. */
-	xfs_iunlink_update_dinode(tp, pag, 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.
- */
-int
-xfs_iunlink(
-	struct xfs_trans	*tp,
-	struct xfs_inode	*ip)
-{
-	struct xfs_mount	*mp = tp->t_mountp;
-	struct xfs_perag	*pag;
-	struct xfs_agi		*agi;
-	struct xfs_buf		*agibp;
-	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;
-
-	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(mp, tp, pag->pag_agno, &agibp);
-	if (error)
-		goto out;
-	agi = agibp->b_addr;
-
-	/*
-	 * 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, pag->pag_agno, next_agino)) {
-		xfs_buf_mark_corrupt(agibp);
-		xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
-		error = -EFSCORRUPTED;
-		goto out;
-	}
-
-	if (next_agino != NULLAGINO) {
-		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, pag, next_agino,
-				&old_agino);
-		if (error)
-			goto out;
-		ASSERT(old_agino == NULLAGINO);
-
-		/*
-		 * agino has been unlinked, add a backref from the next inode
-		 * back to agino.
-		 */
-		error = xfs_iunlink_add_backref(pag, agino, next_agino);
-		if (error)
-			goto out;
-	}
-
-	/* Point the head of the list to point to this inode. */
-	error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino);
-out:
-	xfs_perag_put(pag);
-	return error;
-}
-
-/* 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, bpp);
-	if (error) {
-		xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
-				__func__, error);
-		return error;
-	}
-
-	*dipp = xfs_buf_offset(*bpp, imap->im_boffset);
-	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,
-	struct xfs_perag	*pag,
-	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_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, pag->pag_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, pag->pag_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, pag->pag_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, pag->pag_agno, unlinked_agino) ||
-		    next_agino == unlinked_agino) {
-			XFS_CORRUPTION_ERROR(__func__,
-					XFS_ERRLEVEL_LOW, mp,
-					*dipp, sizeof(**dipp));
-			xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
-			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_perag	*pag,
-	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;
-	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, pag->pag_agno, &agibp);
-	if (error)
-		return error;
-	agi = agibp->b_addr;
-
-	/*
-	 * 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, pag->pag_agno, 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_update_inode(tp, ip, pag, 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) {
-		error = xfs_iunlink_change_backref(pag, next_agino, NULLAGINO);
-		if (error)
-			return error;
-	}
-
-	if (head_agino != agino) {
-		struct xfs_imap	imap;
-		xfs_agino_t	prev_agino;
-
-		/* We need to search the list for the inode being freed. */
-		error = xfs_iunlink_map_prev(tp, pag, head_agino, agino,
-				&prev_agino, &imap, &last_dip, &last_ibp);
-		if (error)
-			return error;
-
-		/* Point the previous inode on the list to the next inode. */
-		xfs_iunlink_update_dinode(tp, pag, 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.
-		 */
-		return xfs_iunlink_change_backref(agibp->b_pag, agino,
-				next_agino);
-	}
-
-	/* Point the head of the list to the next unlinked inode. */
-	return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index,
-			next_agino);
-}
-
-/*
  * Look up the inode number specified and if it is not already marked XFS_ISTALE
  * mark it stale. We should only find clean inodes in this lookup that aren't
  * already stale.
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 0f9babcdb255..04e83e627c34 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -508,10 +508,6 @@ extern struct kmem_zone	*xfs_inode_zone;
 
 bool xfs_inode_needs_inactive(struct xfs_inode *ip);
 
-int xfs_iunlink_init(struct xfs_perag *pag);
-void xfs_iunlink_destroy(struct xfs_perag *pag);
-int xfs_iunlink(struct xfs_trans *tp, struct xfs_inode *ip);
-
 void xfs_end_io(struct work_struct *work);
 
 int xfs_ilock2_io_mmap(struct xfs_inode *ip1, struct xfs_inode *ip2);