[XFS] use filldir internally

Currently xfs has a rather complicated internal scheme to allow for
different directory formats in IRIX. This patch rips all code related to
this out and pushes useage of the Linux filldir callback into the lowlevel
directory code. This does not make the code any less portable because
filldir can be used to create dirents of all possible variations
(including the IRIX ones as proved by the IRIX binary emulation code under
arch/mips/).

This patch get rid of an unessecary copy in the readdir path, about 400
lines of code and one of the last two users of the uio structure.

This version is updated to deal with dmapi aswell which greatly simplifies
the get_dirattrs code. The dmapi part has been tested using the
get_dirattrs tools from the xfstest dmapi suite1 with various small and
large directories.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29478a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>

1 files changed, 30 insertions, 46 deletions

diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index 1b73c9ad646a..e7c12fa1303e 100644
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -749,12 +749,11 @@ xfs_dir2_leaf_compact_x1(
  */
 int						/* error */
 xfs_dir2_leaf_getdents(
-	xfs_trans_t		*tp,		/* transaction pointer */
 	xfs_inode_t		*dp,		/* incore directory inode */
-	uio_t			*uio,		/* I/O control & vectors */
-	int			*eofp,		/* out: reached end of dir */
-	xfs_dirent_t		*dbp,		/* caller's buffer */
-	xfs_dir2_put_t		put)		/* ABI formatting routine */
+	void			*dirent,
+	size_t			bufsize,
+	xfs_off_t		*offset,
+	filldir_t		filldir)
 {
 	xfs_dabuf_t		*bp;		/* data block buffer */
 	int			byteoff;	/* offset in current block */
@@ -763,7 +762,6 @@ xfs_dir2_leaf_getdents(
 	xfs_dir2_data_t		*data;		/* data block structure */
 	xfs_dir2_data_entry_t	*dep;		/* data entry */
 	xfs_dir2_data_unused_t	*dup;		/* unused entry */
-	int			eof;		/* reached end of directory */
 	int			error = 0;	/* error return value */
 	int			i;		/* temporary loop index */
 	int			j;		/* temporary loop index */
@@ -776,46 +774,38 @@ xfs_dir2_leaf_getdents(
 	xfs_mount_t		*mp;		/* filesystem mount point */
 	xfs_dir2_off_t		newoff;		/* new curoff after new blk */
 	int			nmap;		/* mappings to ask xfs_bmapi */
-	xfs_dir2_put_args_t	*p;		/* formatting arg bundle */
 	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 */
+	xfs_ino_t		ino;
 
 	/*
 	 * If the offset is at or past the largest allowed value,
-	 * give up right away, return eof.
+	 * give up right away.
 	 */
-	if (uio->uio_offset >= XFS_DIR2_MAX_DATAPTR) {
-		*eofp = 1;
+	if (*offset >= XFS_DIR2_MAX_DATAPTR)
 		return 0;
-	}
+
 	mp = dp->i_mount;
-	/*
-	 * Setup formatting arguments.
-	 */
-	p = kmem_alloc(sizeof(*p), KM_SLEEP);
-	p->dbp = dbp;
-	p->put = put;
-	p->uio = uio;
+
 	/*
 	 * Set up to bmap a number of blocks based on the caller's
 	 * buffer size, the directory block size, and the filesystem
 	 * block size.
 	 */
-	map_size =
-		howmany(uio->uio_resid + mp->m_dirblksize,
-			mp->m_sb.sb_blocksize);
+	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;
-	eof = 1;
+
 	/*
 	 * Inside the loop we keep the main offset value as a byte offset
 	 * in the directory file.
 	 */
-	curoff = xfs_dir2_dataptr_to_byte(mp, uio->uio_offset);
+	curoff = xfs_dir2_dataptr_to_byte(mp, *offset);
+
 	/*
 	 * Force this conversion through db so we truncate the offset
 	 * down to get the start of the data block.
@@ -836,7 +826,7 @@ xfs_dir2_leaf_getdents(
 			 * take it out of the mapping.
 			 */
 			if (bp) {
-				xfs_da_brelse(tp, bp);
+				xfs_da_brelse(NULL, bp);
 				bp = NULL;
 				map_blocks -= mp->m_dirblkfsbs;
 				/*
@@ -862,8 +852,9 @@ xfs_dir2_leaf_getdents(
 			/*
 			 * Recalculate the readahead blocks wanted.
 			 */
-			ra_want = howmany(uio->uio_resid + mp->m_dirblksize,
+			ra_want = howmany(bufsize + mp->m_dirblksize,
 					  mp->m_sb.sb_blocksize) - 1;
+
 			/*
 			 * If we don't have as many as we want, and we haven't
 			 * run out of data blocks, get some more mappings.
@@ -876,7 +867,7 @@ xfs_dir2_leaf_getdents(
 				 * we already have in the table.
 				 */
 				nmap = map_size - map_valid;
-				error = xfs_bmapi(tp, dp,
+				error = xfs_bmapi(NULL, dp,
 					map_off,
 					xfs_dir2_byte_to_da(mp,
 						XFS_DIR2_LEAF_OFFSET) - map_off,
@@ -939,7 +930,7 @@ xfs_dir2_leaf_getdents(
 			 * mapping.
 			 */
 			curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
-			error = xfs_da_read_buf(tp, dp, 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,
@@ -982,7 +973,7 @@ xfs_dir2_leaf_getdents(
 				 * is a very rare case.
 				 */
 				else if (i > ra_current) {
-					(void)xfs_da_reada_buf(tp, dp,
+					(void)xfs_da_reada_buf(NULL, dp,
 						map[ra_index].br_startoff +
 						ra_offset, XFS_DATA_FORK);
 					ra_current = i;
@@ -1089,46 +1080,39 @@ xfs_dir2_leaf_getdents(
 		 */
 		dep = (xfs_dir2_data_entry_t *)ptr;
 
-		p->namelen = dep->namelen;
-
-		length = xfs_dir2_data_entsize(p->namelen);
-
-		p->cook = xfs_dir2_byte_to_dataptr(mp, curoff + length);
+		length = xfs_dir2_data_entsize(dep->namelen);
 
-		p->ino = be64_to_cpu(dep->inumber);
+		ino = be64_to_cpu(dep->inumber);
 #if XFS_BIG_INUMS
-		p->ino += mp->m_inoadd;
+		ino += mp->m_inoadd;
 #endif
-		p->name = (char *)dep->name;
-
-		error = p->put(p);
 
 		/*
 		 * Won't fit.  Return to caller.
 		 */
-		if (!p->done) {
-			eof = 0;
+		if (filldir(dirent, dep->name, dep->namelen,
+			    xfs_dir2_byte_to_dataptr(mp, curoff + length),
+			    ino, DT_UNKNOWN))
 			break;
-		}
+
 		/*
 		 * Advance to next entry in the block.
 		 */
 		ptr += length;
 		curoff += length;
+		bufsize -= length;
 	}
 
 	/*
 	 * All done.  Set output offset value to current offset.
 	 */
-	*eofp = eof;
 	if (curoff > xfs_dir2_dataptr_to_byte(mp, XFS_DIR2_MAX_DATAPTR))
-		uio->uio_offset = XFS_DIR2_MAX_DATAPTR;
+		*offset = XFS_DIR2_MAX_DATAPTR;
 	else
-		uio->uio_offset = xfs_dir2_byte_to_dataptr(mp, curoff);
+		*offset = xfs_dir2_byte_to_dataptr(mp, curoff);
 	kmem_free(map, map_size * sizeof(*map));
-	kmem_free(p, sizeof(*p));
 	if (bp)
-		xfs_da_brelse(tp, bp);
+		xfs_da_brelse(NULL, bp);
 	return error;
 }