1 files changed, 232 insertions, 202 deletions

diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index 69accf6cbc46..0b296253bd01 100644
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -759,6 +759,218 @@ xfs_dir2_leaf_compact_x1(
 	*highstalep = highstale;
 }
 
+struct xfs_dir2_leaf_map_info {
+	xfs_extlen_t	map_blocks;	/* number of fsbs in map */
+	xfs_dablk_t	map_off;	/* last mapped file offset */
+	int		map_size;	/* total entries in *map */
+	int		map_valid;	/* valid entries in *map */
+	int		nmap;		/* mappings to ask xfs_bmapi */
+	xfs_dir2_db_t	curdb;		/* db for current block */
+	int		ra_current;	/* number of read-ahead blks */
+	int		ra_index;	/* *map index for read-ahead */
+	int		ra_offset;	/* map entry offset for ra */
+	int		ra_want;	/* readahead count wanted */
+	struct xfs_bmbt_irec map[];	/* map vector for blocks */
+};
+
+STATIC int
+xfs_dir2_leaf_readbuf(
+	struct xfs_inode	*dp,
+	size_t			bufsize,
+	struct xfs_dir2_leaf_map_info *mip,
+	xfs_dir2_off_t		*curoff,
+	struct xfs_buf		**bpp)
+{
+	struct xfs_mount	*mp = dp->i_mount;
+	struct xfs_buf		*bp = *bpp;
+	struct xfs_bmbt_irec	*map = mip->map;
+	int			error = 0;
+	int			length;
+	int			i;
+	int			j;
+
+	/*
+	 * If we have a buffer, we need to release it and
+	 * take it out of the mapping.
+	 */
+
+	if (bp) {
+		xfs_trans_brelse(NULL, bp);
+		bp = NULL;
+		mip->map_blocks -= mp->m_dirblkfsbs;
+		/*
+		 * Loop to get rid of the extents for the
+		 * directory block.
+		 */
+		for (i = mp->m_dirblkfsbs; i > 0; ) {
+			j = min_t(int, map->br_blockcount, i);
+			map->br_blockcount -= j;
+			map->br_startblock += j;
+			map->br_startoff += j;
+			/*
+			 * If mapping is done, pitch it from
+			 * the table.
+			 */
+			if (!map->br_blockcount && --mip->map_valid)
+				memmove(&map[0], &map[1],
+					sizeof(map[0]) * mip->map_valid);
+			i -= j;
+		}
+	}
+
+	/*
+	 * Recalculate the readahead blocks wanted.
+	 */
+	mip->ra_want = howmany(bufsize + mp->m_dirblksize,
+			       mp->m_sb.sb_blocksize) - 1;
+	ASSERT(mip->ra_want >= 0);
+
+	/*
+	 * If we don't have as many as we want, and we haven't
+	 * run out of data blocks, get some more mappings.
+	 */
+	if (1 + mip->ra_want > mip->map_blocks &&
+	    mip->map_off < xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET)) {
+		/*
+		 * Get more bmaps, fill in after the ones
+		 * we already have in the table.
+		 */
+		mip->nmap = mip->map_size - mip->map_valid;
+		error = xfs_bmapi_read(dp, mip->map_off,
+				xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET) -
+								mip->map_off,
+				&map[mip->map_valid], &mip->nmap, 0);
+
+		/*
+		 * Don't know if we should ignore this or try to return an
+		 * error.  The trouble with returning errors is that readdir
+		 * will just stop without actually passing the error through.
+		 */
+		if (error)
+			goto out;	/* XXX */
+
+		/*
+		 * If we got all the mappings we asked for, set the final map
+		 * offset based on the last bmap value received.  Otherwise,
+		 * we've reached the end.
+		 */
+		if (mip->nmap == mip->map_size - mip->map_valid) {
+			i = mip->map_valid + mip->nmap - 1;
+			mip->map_off = map[i].br_startoff + map[i].br_blockcount;
+		} else
+			mip->map_off = xfs_dir2_byte_to_da(mp,
+							XFS_DIR2_LEAF_OFFSET);
+
+		/*
+		 * Look for holes in the mapping, and eliminate them.  Count up
+		 * the valid blocks.
+		 */
+		for (i = mip->map_valid; i < mip->map_valid + mip->nmap; ) {
+			if (map[i].br_startblock == HOLESTARTBLOCK) {
+				mip->nmap--;
+				length = mip->map_valid + mip->nmap - i;
+				if (length)
+					memmove(&map[i], &map[i + 1],
+						sizeof(map[i]) * length);
+			} else {
+				mip->map_blocks += map[i].br_blockcount;
+				i++;
+			}
+		}
+		mip->map_valid += mip->nmap;
+	}
+
+	/*
+	 * No valid mappings, so no more data blocks.
+	 */
+	if (!mip->map_valid) {
+		*curoff = xfs_dir2_da_to_byte(mp, mip->map_off);
+		goto out;
+	}
+
+	/*
+	 * Read the directory block starting at the first mapping.
+	 */
+	mip->curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
+	error = xfs_da_read_buf(NULL, dp, map->br_startoff,
+			map->br_blockcount >= mp->m_dirblkfsbs ?
+			    XFS_FSB_TO_DADDR(mp, map->br_startblock) : -1,
+			&bp, XFS_DATA_FORK);
+
+	/*
+	 * Should just skip over the data block instead of giving up.
+	 */
+	if (error)
+		goto out;	/* XXX */
+
+	/*
+	 * Adjust the current amount of read-ahead: we just read a block that
+	 * was previously ra.
+	 */
+	if (mip->ra_current)
+		mip->ra_current -= mp->m_dirblkfsbs;
+
+	/*
+	 * Do we need more readahead?
+	 */
+	for (mip->ra_index = mip->ra_offset = i = 0;
+	     mip->ra_want > mip->ra_current && i < mip->map_blocks;
+	     i += mp->m_dirblkfsbs) {
+		ASSERT(mip->ra_index < mip->map_valid);
+		/*
+		 * Read-ahead a contiguous directory block.
+		 */
+		if (i > mip->ra_current &&
+		    map[mip->ra_index].br_blockcount >= mp->m_dirblkfsbs) {
+			xfs_buf_readahead(mp->m_ddev_targp,
+				XFS_FSB_TO_DADDR(mp,
+					map[mip->ra_index].br_startblock +
+							mip->ra_offset),
+				(int)BTOBB(mp->m_dirblksize));
+			mip->ra_current = i;
+		}
+
+		/*
+		 * Read-ahead a non-contiguous directory block.  This doesn't
+		 * use our mapping, but this is a very rare case.
+		 */
+		else if (i > mip->ra_current) {
+			xfs_da_reada_buf(NULL, dp,
+					map[mip->ra_index].br_startoff +
+							mip->ra_offset,
+					XFS_DATA_FORK);
+			mip->ra_current = i;
+		}
+
+		/*
+		 * Advance offset through the mapping table.
+		 */
+		for (j = 0; j < mp->m_dirblkfsbs; j++) {
+			/*
+			 * The rest of this extent but not more than a dir
+			 * block.
+			 */
+			length = min_t(int, mp->m_dirblkfsbs,
+					map[mip->ra_index].br_blockcount -
+							mip->ra_offset);
+			j += length;
+			mip->ra_offset += length;
+
+			/*
+			 * Advance to the next mapping if this one is used up.
+			 */
+			if (mip->ra_offset == map[mip->ra_index].br_blockcount) {
+				mip->ra_offset = 0;
+				mip->ra_index++;
+			}
+		}
+	}
+
+out:
+	*bpp = bp;
+	return error;
+}
+
 /*
  * Getdents (readdir) for leaf and node directories.
  * This reads the data blocks only, so is the same for both forms.
@@ -771,30 +983,18 @@ xfs_dir2_leaf_getdents(
 	xfs_off_t		*offset,
 	filldir_t		filldir)
 {
-	struct xfs_buf		*bp;		/* data block buffer */
-	int			byteoff;	/* offset in current block */
-	xfs_dir2_db_t		curdb;		/* db for current block */
-	xfs_dir2_off_t		curoff;		/* current overall offset */
+	struct xfs_buf		*bp = NULL;	/* data block buffer */
 	xfs_dir2_data_hdr_t	*hdr;		/* data block header */
 	xfs_dir2_data_entry_t	*dep;		/* data entry */
 	xfs_dir2_data_unused_t	*dup;		/* unused entry */
 	int			error = 0;	/* error return value */
-	int			i;		/* temporary loop index */
-	int			j;		/* temporary loop index */
 	int			length;		/* temporary length value */
-	xfs_bmbt_irec_t		*map;		/* map vector for blocks */
-	xfs_extlen_t		map_blocks;	/* number of fsbs in map */
-	xfs_dablk_t		map_off;	/* last mapped file offset */
-	int			map_size;	/* total entries in *map */
-	int			map_valid;	/* valid entries in *map */
 	xfs_mount_t		*mp;		/* filesystem mount point */
+	int			byteoff;	/* offset in current block */
+	xfs_dir2_off_t		curoff;		/* current overall offset */
 	xfs_dir2_off_t		newoff;		/* new curoff after new blk */
-	int			nmap;		/* mappings to ask xfs_bmapi */
 	char			*ptr = NULL;	/* pointer to current data */
-	int			ra_current;	/* number of read-ahead blks */
-	int			ra_index;	/* *map index for read-ahead */
-	int			ra_offset;	/* map entry offset for ra */
-	int			ra_want;	/* readahead count wanted */
+	struct xfs_dir2_leaf_map_info *map_info;
 
 	/*
 	 * If the offset is at or past the largest allowed value,
@@ -810,10 +1010,12 @@ xfs_dir2_leaf_getdents(
 	 * buffer size, the directory block size, and the filesystem
 	 * block size.
 	 */
-	map_size = howmany(bufsize + mp->m_dirblksize, mp->m_sb.sb_blocksize);
-	map = kmem_alloc(map_size * sizeof(*map), KM_SLEEP);
-	map_valid = ra_index = ra_offset = ra_current = map_blocks = 0;
-	bp = NULL;
+	length = howmany(bufsize + mp->m_dirblksize,
+				     mp->m_sb.sb_blocksize);
+	map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) +
+				(length * sizeof(struct xfs_bmbt_irec)),
+			       KM_SLEEP);
+	map_info->map_size = length;
 
 	/*
 	 * Inside the loop we keep the main offset value as a byte offset
@@ -825,7 +1027,9 @@ xfs_dir2_leaf_getdents(
 	 * Force this conversion through db so we truncate the offset
 	 * down to get the start of the data block.
 	 */
-	map_off = xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, curoff));
+	map_info->map_off = xfs_dir2_db_to_da(mp,
+					      xfs_dir2_byte_to_db(mp, curoff));
+
 	/*
 	 * Loop over directory entries until we reach the end offset.
 	 * Get more blocks and readahead as necessary.
@@ -836,190 +1040,16 @@ xfs_dir2_leaf_getdents(
 		 * current buffer, need to get another one.
 		 */
 		if (!bp || ptr >= (char *)bp->b_addr + mp->m_dirblksize) {
-			/*
-			 * If we have a buffer, we need to release it and
-			 * take it out of the mapping.
-			 */
-			if (bp) {
-				xfs_trans_brelse(NULL, bp);
-				bp = NULL;
-				map_blocks -= mp->m_dirblkfsbs;
-				/*
-				 * Loop to get rid of the extents for the
-				 * directory block.
-				 */
-				for (i = mp->m_dirblkfsbs; i > 0; ) {
-					j = MIN((int)map->br_blockcount, i);
-					map->br_blockcount -= j;
-					map->br_startblock += j;
-					map->br_startoff += j;
-					/*
-					 * If mapping is done, pitch it from
-					 * the table.
-					 */
-					if (!map->br_blockcount && --map_valid)
-						memmove(&map[0], &map[1],
-							sizeof(map[0]) *
-							map_valid);
-					i -= j;
-				}
-			}
-			/*
-			 * Recalculate the readahead blocks wanted.
-			 */
-			ra_want = howmany(bufsize + mp->m_dirblksize,
-					  mp->m_sb.sb_blocksize) - 1;
-			ASSERT(ra_want >= 0);
 
-			/*
-			 * If we don't have as many as we want, and we haven't
-			 * run out of data blocks, get some more mappings.
-			 */
-			if (1 + ra_want > map_blocks &&
-			    map_off <
-			    xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET)) {
-				/*
-				 * Get more bmaps, fill in after the ones
-				 * we already have in the table.
-				 */
-				nmap = map_size - map_valid;
-				error = xfs_bmapi_read(dp, map_off,
-					xfs_dir2_byte_to_da(mp,
-						XFS_DIR2_LEAF_OFFSET) - map_off,
-					&map[map_valid], &nmap, 0);
-				/*
-				 * Don't know if we should ignore this or
-				 * try to return an error.
-				 * The trouble with returning errors
-				 * is that readdir will just stop without
-				 * actually passing the error through.
-				 */
-				if (error)
-					break;	/* XXX */
-				/*
-				 * If we got all the mappings we asked for,
-				 * set the final map offset based on the
-				 * last bmap value received.
-				 * Otherwise, we've reached the end.
-				 */
-				if (nmap == map_size - map_valid)
-					map_off =
-					map[map_valid + nmap - 1].br_startoff +
-					map[map_valid + nmap - 1].br_blockcount;
-				else
-					map_off =
-						xfs_dir2_byte_to_da(mp,
-							XFS_DIR2_LEAF_OFFSET);
-				/*
-				 * Look for holes in the mapping, and
-				 * eliminate them.  Count up the valid blocks.
-				 */
-				for (i = map_valid; i < map_valid + nmap; ) {
-					if (map[i].br_startblock ==
-					    HOLESTARTBLOCK) {
-						nmap--;
-						length = map_valid + nmap - i;
-						if (length)
-							memmove(&map[i],
-								&map[i + 1],
-								sizeof(map[i]) *
-								length);
-					} else {
-						map_blocks +=
-							map[i].br_blockcount;
-						i++;
-					}
-				}
-				map_valid += nmap;
-			}
-			/*
-			 * No valid mappings, so no more data blocks.
-			 */
-			if (!map_valid) {
-				curoff = xfs_dir2_da_to_byte(mp, map_off);
+			error = xfs_dir2_leaf_readbuf(dp, bufsize, map_info,
+						      &curoff, &bp);
+			if (error || !map_info->map_valid)
 				break;
-			}
-			/*
-			 * Read the directory block starting at the first
-			 * mapping.
-			 */
-			curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
-			error = xfs_da_read_buf(NULL, dp, map->br_startoff,
-				map->br_blockcount >= mp->m_dirblkfsbs ?
-				    XFS_FSB_TO_DADDR(mp, map->br_startblock) :
-				    -1,
-				&bp, XFS_DATA_FORK);
-			/*
-			 * Should just skip over the data block instead
-			 * of giving up.
-			 */
-			if (error)
-				break;	/* XXX */
-			/*
-			 * Adjust the current amount of read-ahead: we just
-			 * read a block that was previously ra.
-			 */
-			if (ra_current)
-				ra_current -= mp->m_dirblkfsbs;
-			/*
-			 * Do we need more readahead?
-			 */
-			for (ra_index = ra_offset = i = 0;
-			     ra_want > ra_current && i < map_blocks;
-			     i += mp->m_dirblkfsbs) {
-				ASSERT(ra_index < map_valid);
-				/*
-				 * Read-ahead a contiguous directory block.
-				 */
-				if (i > ra_current &&
-				    map[ra_index].br_blockcount >=
-				    mp->m_dirblkfsbs) {
-					xfs_buf_readahead(mp->m_ddev_targp,
-						XFS_FSB_TO_DADDR(mp,
-						   map[ra_index].br_startblock +
-						   ra_offset),
-						(int)BTOBB(mp->m_dirblksize));
-					ra_current = i;
-				}
-				/*
-				 * Read-ahead a non-contiguous directory block.
-				 * This doesn't use our mapping, but this
-				 * is a very rare case.
-				 */
-				else if (i > ra_current) {
-					(void)xfs_da_reada_buf(NULL, dp,
-						map[ra_index].br_startoff +
-						ra_offset, XFS_DATA_FORK);
-					ra_current = i;
-				}
-				/*
-				 * Advance offset through the mapping table.
-				 */
-				for (j = 0; j < mp->m_dirblkfsbs; j++) {
-					/*
-					 * The rest of this extent but not
-					 * more than a dir block.
-					 */
-					length = MIN(mp->m_dirblkfsbs,
-						(int)(map[ra_index].br_blockcount -
-						ra_offset));
-					j += length;
-					ra_offset += length;
-					/*
-					 * Advance to the next mapping if
-					 * this one is used up.
-					 */
-					if (ra_offset ==
-					    map[ra_index].br_blockcount) {
-						ra_offset = 0;
-						ra_index++;
-					}
-				}
-			}
+
 			/*
 			 * Having done a read, we need to set a new offset.
 			 */
-			newoff = xfs_dir2_db_off_to_byte(mp, curdb, 0);
+			newoff = xfs_dir2_db_off_to_byte(mp, map_info->curdb, 0);
 			/*
 			 * Start of the current block.
 			 */
@@ -1030,7 +1060,7 @@ xfs_dir2_leaf_getdents(
 			 */
 			else if (curoff > newoff)
 				ASSERT(xfs_dir2_byte_to_db(mp, curoff) ==
-				       curdb);
+				       map_info->curdb);
 			hdr = bp->b_addr;
 			xfs_dir2_data_check(dp, bp);
 			/*
@@ -1113,7 +1143,7 @@ xfs_dir2_leaf_getdents(
 		*offset = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
 	else
 		*offset = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
-	kmem_free(map);
+	kmem_free(map_info);
 	if (bp)
 		xfs_trans_brelse(NULL, bp);
 	return error;