[XFS] Fix an infinite loop issue in bulkstat when a corrupt inode is

detected.  Thanks to Roger Willcocks.

SGI-PV: 951054
SGI-Modid: xfs-linux-melb:xfs-kern:25477a
Signed-off-by: Nathan Scott <nathans@sgi.com>

fs/xfs/xfs_inode.c

@@ -253,7 +253,8 @@ xfs_itobp(
 	xfs_inode_t	*ip,
 	xfs_dinode_t	**dipp,
 	xfs_buf_t	**bpp,
-	xfs_daddr_t	bno)
+	xfs_daddr_t	bno,
+	uint		imap_flags)
 {
 	xfs_buf_t	*bp;
 	int		error;
@@ -269,10 +270,9 @@ xfs_itobp(
 		 * inode on disk.
 		 */
 		imap.im_blkno = bno;
-		error = xfs_imap(mp, tp, ip->i_ino, &imap, XFS_IMAP_LOOKUP);
-		if (error != 0) {
+		if ((error = xfs_imap(mp, tp, ip->i_ino, &imap,
+					XFS_IMAP_LOOKUP | imap_flags)))
 			return error;
-		}
 
 		/*
 		 * If the inode number maps to a block outside the bounds
@@ -336,9 +336,10 @@ xfs_itobp(
 	 * (if DEBUG kernel) or the first inode in the buffer, otherwise.
 	 */
 #ifdef DEBUG
-	ni = BBTOB(imap.im_len) >> mp->m_sb.sb_inodelog;
+	ni = (imap_flags & XFS_IMAP_BULKSTAT) ? 0 :
+		(BBTOB(imap.im_len) >> mp->m_sb.sb_inodelog);
 #else
-	ni = 1;
+	ni = (imap_flags & XFS_IMAP_BULKSTAT) ? 0 : 1;
 #endif
 	for (i = 0; i < ni; i++) {
 		int		di_ok;
@@ -868,9 +869,8 @@ xfs_iread(
 	 * return NULL as well.  Set i_blkno to 0 so that xfs_itobp() will
 	 * know that this is a new incore inode.
 	 */
-	error = xfs_itobp(mp, tp, ip, &dip, &bp, bno);
-
-	if (error != 0) {
+	error = xfs_itobp(mp, tp, ip, &dip, &bp, bno, 0);
+	if (error) {
 		kmem_zone_free(xfs_inode_zone, ip);
 		return error;
 	}
@@ -1895,7 +1895,7 @@ xfs_iunlink(
 		 * Here we put the head pointer into our next pointer,
 		 * and then we fall through to point the head at us.
 		 */
-		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
+		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0, 0);
 		if (error) {
 			return error;
 		}
@@ -2004,7 +2004,7 @@ xfs_iunlink_remove(
 		 * of dealing with the buffer when there is no need to
 		 * change it.
 		 */
-		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
+		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0, 0);
 		if (error) {
 			cmn_err(CE_WARN,
 				"xfs_iunlink_remove: xfs_itobp()  returned an error %d on %s.  Returning error.",
@@ -2066,7 +2066,7 @@ xfs_iunlink_remove(
 		 * Now last_ibp points to the buffer previous to us on
 		 * the unlinked list.  Pull us from the list.
 		 */
-		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
+		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0, 0);
 		if (error) {
 			cmn_err(CE_WARN,
 				"xfs_iunlink_remove: xfs_itobp()  returned an error %d on %s.  Returning error.",
@@ -3023,8 +3023,8 @@ xfs_iflush(
 	/*
 	 * Get the buffer containing the on-disk inode.
 	 */
-	error = xfs_itobp(mp, NULL, ip, &dip, &bp, 0);
-	if (error != 0) {
+	error = xfs_itobp(mp, NULL, ip, &dip, &bp, 0, 0);
+	if (error) {
 		xfs_ifunlock(ip);
 		return error;
 	}

fs/xfs/xfs_inode.h

@@ -95,9 +95,10 @@ typedef struct xfs_ifork {
 #define	XFS_IFEXTIREC	0x08	/* Indirection array of extent blocks */
 
 /*
- * Flags for xfs_imap() and xfs_dilocate().
+ * Flags for xfs_itobp(), xfs_imap() and xfs_dilocate().
  */
-#define	XFS_IMAP_LOOKUP		0x1
+#define XFS_IMAP_LOOKUP		0x1
+#define XFS_IMAP_BULKSTAT	0x2
 
 #ifdef __KERNEL__
 struct bhv_desc;
@@ -421,7 +422,7 @@ int		xfs_finish_reclaim_all(struct xfs_mount *, int);
  */
 int		xfs_itobp(struct xfs_mount *, struct xfs_trans *,
 			  xfs_inode_t *, xfs_dinode_t **, struct xfs_buf **,
-			  xfs_daddr_t);
+			  xfs_daddr_t, uint);
 int		xfs_iread(struct xfs_mount *, struct xfs_trans *, xfs_ino_t,
 			  xfs_inode_t **, xfs_daddr_t);
 int		xfs_iread_extents(struct xfs_trans *, xfs_inode_t *, int);

fs/xfs/xfs_itable.c

@@ -562,7 +562,8 @@ xfs_bulkstat(
 						if (bp)
 							xfs_buf_relse(bp);
 						error = xfs_itobp(mp, NULL, ip,
-								  &dip, &bp, bno);
+								&dip, &bp, bno,
+								XFS_IMAP_BULKSTAT);
 						if (!error)
 							clustidx = ip->i_boffset / mp->m_sb.sb_inodesize;
 						kmem_zone_free(xfs_inode_zone, ip);
@@ -570,6 +571,8 @@ xfs_bulkstat(
 								   mp, XFS_ERRTAG_BULKSTAT_READ_CHUNK,
 								   XFS_RANDOM_BULKSTAT_READ_CHUNK)) {
 							bp = NULL;
+							ubleft = 0;
+							rval = error;
 							break;
 						}
 					}

fs/xfs/xfs_log_recover.c

@@ -3249,7 +3249,7 @@ xlog_recover_process_iunlinks(
 					 * next inode in the bucket.
 					 */
 					error = xfs_itobp(mp, NULL, ip, &dip,
-							&ibp, 0);
+							&ibp, 0, 0);
 					ASSERT(error || (dip != NULL));
 				}
 

fs/xfs/xfs_vfsops.c

@@ -1229,7 +1229,7 @@ xfs_sync_inodes(
 					xfs_iunlock(ip, XFS_ILOCK_SHARED);
 
 					error = xfs_itobp(mp, NULL, ip,
-							  &dip, &bp, 0);
+							  &dip, &bp, 0, 0);
 					if (!error) {
 						xfs_buf_relse(bp);
 					} else {