xfs: kill XBF_LOCK

Buffers are always returned locked from the lookup routines. Hence
we don't need to tell the lookup routines to return locked buffers,
on to try and lock them. Remove XBF_LOCK from all the callers and
from internal buffer cache usage.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

fs/xfs/xfs_attr.c

@@ -1988,8 +1988,7 @@ xfs_attr_rmtval_get(xfs_da_args_t *args)
 			dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
 			blkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
 			error = xfs_read_buf(mp, mp->m_ddev_targp, dblkno,
-					     blkcnt, XBF_LOCK | XBF_DONT_BLOCK,
-					     &bp);
+					     blkcnt, XBF_DONT_BLOCK, &bp);
 			if (error)
 				return(error);
 
@@ -2116,7 +2115,7 @@ xfs_attr_rmtval_set(xfs_da_args_t *args)
 		blkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount);
 
 		bp = xfs_buf_get(mp->m_ddev_targp, dblkno, blkcnt,
-				 XBF_LOCK | XBF_DONT_BLOCK);
+				 XBF_DONT_BLOCK);
 		if (!bp)
 			return ENOMEM;
 

fs/xfs/xfs_attr_leaf.c

@@ -2983,7 +2983,7 @@ xfs_attr_leaf_freextent(xfs_trans_t **trans, xfs_inode_t *dp,
 						map.br_blockcount);
 			bp = xfs_trans_get_buf(*trans,
 					dp->i_mount->m_ddev_targp,
-					dblkno, dblkcnt, XBF_LOCK);
+					dblkno, dblkcnt, 0);
 			if (!bp)
 				return ENOMEM;
 			xfs_trans_binval(*trans, bp);

fs/xfs/xfs_buf.c

@@ -185,7 +185,7 @@ xfs_buf_alloc(
 	/*
 	 * We don't want certain flags to appear in b_flags.
 	 */
-	flags &= ~(XBF_LOCK|XBF_MAPPED|XBF_DONT_BLOCK|XBF_READ_AHEAD);
+	flags &= ~(XBF_MAPPED|XBF_DONT_BLOCK|XBF_READ_AHEAD);
 
 	atomic_set(&bp->b_hold, 1);
 	atomic_set(&bp->b_lru_ref, 1);
@@ -584,19 +584,14 @@ xfs_buf_get(
 		if (unlikely(error)) {
 			xfs_warn(target->bt_mount,
 				"%s: failed to map pages\n", __func__);
-			goto no_buffer;
+			xfs_buf_relse(bp);
+			return NULL;
 		}
 	}
 
 	XFS_STATS_INC(xb_get);
 	trace_xfs_buf_get(bp, flags, _RET_IP_);
 	return bp;
-
-no_buffer:
-	if (flags & (XBF_LOCK | XBF_TRYLOCK))
-		xfs_buf_unlock(bp);
-	xfs_buf_rele(bp);
-	return NULL;
 }
 
 STATIC int
@@ -639,7 +634,8 @@ xfs_buf_read(
 			 * Read ahead call which is already satisfied,
 			 * drop the buffer
 			 */
-			goto no_buffer;
+			xfs_buf_relse(bp);
+			return NULL;
 		} else {
 			/* We do not want read in the flags */
 			bp->b_flags &= ~XBF_READ;
@@ -647,12 +643,6 @@ xfs_buf_read(
 	}
 
 	return bp;
-
- no_buffer:
-	if (flags & (XBF_LOCK | XBF_TRYLOCK))
-		xfs_buf_unlock(bp);
-	xfs_buf_rele(bp);
-	return NULL;
 }
 
 /*

fs/xfs/xfs_buf.h

@@ -52,7 +52,6 @@ typedef enum {
 #define XBF_FLUSH	(1 << 12)/* flush the disk cache before a write */
 
 /* flags used only as arguments to access routines */
-#define XBF_LOCK	(1 << 15)/* lock requested */
 #define XBF_TRYLOCK	(1 << 16)/* lock requested, but do not wait */
 #define XBF_DONT_BLOCK	(1 << 17)/* do not block in current thread */
 
@@ -74,8 +73,7 @@ typedef unsigned int xfs_buf_flags_t;
 	{ XBF_SYNCIO,		"SYNCIO" }, \
 	{ XBF_FUA,		"FUA" }, \
 	{ XBF_FLUSH,		"FLUSH" }, \
-	{ XBF_LOCK,		"LOCK" },  	/* should never be set */\
-	{ XBF_TRYLOCK,		"TRYLOCK" }, 	/* ditto */\
+	{ XBF_TRYLOCK,		"TRYLOCK" }, 	/* should never be set */\
 	{ XBF_DONT_BLOCK,	"DONT_BLOCK" },	/* ditto */\
 	{ _XBF_PAGES,		"PAGES" }, \
 	{ _XBF_KMEM,		"KMEM" }, \

fs/xfs/xfs_fsops.c

@@ -193,7 +193,7 @@ xfs_growfs_data_private(
 		 */
 		bp = xfs_buf_get(mp->m_ddev_targp,
 				 XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
-				 XFS_FSS_TO_BB(mp, 1), XBF_LOCK | XBF_MAPPED);
+				 XFS_FSS_TO_BB(mp, 1), XBF_MAPPED);
 		if (!bp) {
 			error = ENOMEM;
 			goto error0;
@@ -230,7 +230,7 @@ xfs_growfs_data_private(
 		 */
 		bp = xfs_buf_get(mp->m_ddev_targp,
 				 XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
-				 XFS_FSS_TO_BB(mp, 1), XBF_LOCK | XBF_MAPPED);
+				 XFS_FSS_TO_BB(mp, 1), XBF_MAPPED);
 		if (!bp) {
 			error = ENOMEM;
 			goto error0;
@@ -259,8 +259,7 @@ xfs_growfs_data_private(
 		 */
 		bp = xfs_buf_get(mp->m_ddev_targp,
 				 XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
-				 BTOBB(mp->m_sb.sb_blocksize),
-				 XBF_LOCK | XBF_MAPPED);
+				 BTOBB(mp->m_sb.sb_blocksize), XBF_MAPPED);
 		if (!bp) {
 			error = ENOMEM;
 			goto error0;
@@ -286,8 +285,7 @@ xfs_growfs_data_private(
 		 */
 		bp = xfs_buf_get(mp->m_ddev_targp,
 				 XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
-				 BTOBB(mp->m_sb.sb_blocksize),
-				 XBF_LOCK | XBF_MAPPED);
+				 BTOBB(mp->m_sb.sb_blocksize), XBF_MAPPED);
 		if (!bp) {
 			error = ENOMEM;
 			goto error0;
@@ -314,8 +312,7 @@ xfs_growfs_data_private(
 		 */
 		bp = xfs_buf_get(mp->m_ddev_targp,
 				 XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
-				 BTOBB(mp->m_sb.sb_blocksize),
-				 XBF_LOCK | XBF_MAPPED);
+				 BTOBB(mp->m_sb.sb_blocksize), XBF_MAPPED);
 		if (!bp) {
 			error = ENOMEM;
 			goto error0;

fs/xfs/xfs_ialloc.c

@@ -200,8 +200,7 @@ xfs_ialloc_inode_init(
 		 */
 		d = XFS_AGB_TO_DADDR(mp, agno, agbno + (j * blks_per_cluster));
 		fbuf = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
-					 mp->m_bsize * blks_per_cluster,
-					 XBF_LOCK);
+					 mp->m_bsize * blks_per_cluster, 0);
 		if (!fbuf)
 			return ENOMEM;
 		/*

fs/xfs/xfs_inode.c

@@ -226,7 +226,7 @@ xfs_inotobp(
 	if (error)
 		return error;
 
-	error = xfs_imap_to_bp(mp, tp, &imap, &bp, XBF_LOCK, imap_flags);
+	error = xfs_imap_to_bp(mp, tp, &imap, &bp, 0, imap_flags);
 	if (error)
 		return error;
 
@@ -782,8 +782,7 @@ xfs_iread(
 	/*
 	 * Get pointers to the on-disk inode and the buffer containing it.
 	 */
-	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp,
-			       XBF_LOCK, iget_flags);
+	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp, 0, iget_flags);
 	if (error)
 		return error;
 	dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
@@ -1342,7 +1341,7 @@ 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, XBF_LOCK);
+		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
 		if (error)
 			return error;
 
@@ -1423,7 +1422,7 @@ xfs_iunlink_remove(
 		 * of dealing with the buffer when there is no need to
 		 * change it.
 		 */
-		error = xfs_itobp(mp, tp, ip, &dip, &ibp, XBF_LOCK);
+		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
 		if (error) {
 			xfs_warn(mp, "%s: xfs_itobp() returned error %d.",
 				__func__, error);
@@ -1484,7 +1483,7 @@ 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, XBF_LOCK);
+		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
 		if (error) {
 			xfs_warn(mp, "%s: xfs_itobp(2) returned error %d.",
 				__func__, error);
@@ -1566,8 +1565,7 @@ xfs_ifree_cluster(
 		 * to mark all the active inodes on the buffer stale.
 		 */
 		bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
-					mp->m_bsize * blks_per_cluster,
-					XBF_LOCK);
+					mp->m_bsize * blks_per_cluster, 0);
 
 		if (!bp)
 			return ENOMEM;
@@ -1737,7 +1735,7 @@ xfs_ifree(
 
 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 
-	error = xfs_itobp(ip->i_mount, tp, ip, &dip, &ibp, XBF_LOCK);
+	error = xfs_itobp(ip->i_mount, tp, ip, &dip, &ibp, 0);
 	if (error)
 		return error;
 

fs/xfs/xfs_log_recover.c

@@ -2131,7 +2131,7 @@ xlog_recover_buffer_pass2(
 
 	trace_xfs_log_recover_buf_recover(log, buf_f);
 
-	buf_flags = XBF_LOCK;
+	buf_flags = 0;
 	if (!(buf_f->blf_flags & XFS_BLF_INODE_BUF))
 		buf_flags |= XBF_MAPPED;
 
@@ -2229,8 +2229,7 @@ xlog_recover_inode_pass2(
 	}
 	trace_xfs_log_recover_inode_recover(log, in_f);
 
-	bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len,
-			  XBF_LOCK);
+	bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len, 0);
 	if (!bp) {
 		error = ENOMEM;
 		goto error;
@@ -3103,7 +3102,7 @@ xlog_recover_process_one_iunlink(
 	/*
 	 * Get the on disk inode to find the next inode in the bucket.
 	 */
-	error = xfs_itobp(mp, NULL, ip, &dip, &ibp, XBF_LOCK);
+	error = xfs_itobp(mp, NULL, ip, &dip, &ibp, 0);
 	if (error)
 		goto fail_iput;
 

fs/xfs/xfs_rw.c

@@ -114,7 +114,7 @@ xfs_read_buf(
 	int		 error;
 
 	if (!flags)
-		flags = XBF_LOCK | XBF_MAPPED;
+		flags = XBF_MAPPED;
 
 	bp = xfs_buf_read(target, blkno, len, flags);
 	if (!bp)

fs/xfs/xfs_trans_buf.c

@@ -142,7 +142,7 @@ xfs_trans_get_buf(xfs_trans_t	*tp,
 	xfs_buf_log_item_t	*bip;
 
 	if (flags == 0)
-		flags = XBF_LOCK | XBF_MAPPED;
+		flags = XBF_MAPPED;
 
 	/*
 	 * Default to a normal get_buf() call if the tp is NULL.
@@ -275,7 +275,7 @@ xfs_trans_read_buf(
 	int			error;
 
 	if (flags == 0)
-		flags = XBF_LOCK | XBF_MAPPED;
+		flags = XBF_MAPPED;
 
 	/*
 	 * Default to a normal get_buf() call if the tp is NULL.

fs/xfs/xfs_vnodeops.c

@@ -82,7 +82,7 @@ xfs_readlink_bmap(
 		byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
 
 		bp = xfs_buf_read(mp->m_ddev_targp, d, BTOBB(byte_cnt),
-				  XBF_LOCK | XBF_MAPPED | XBF_DONT_BLOCK);
+				  XBF_MAPPED | XBF_DONT_BLOCK);
 		if (!bp)
 			return XFS_ERROR(ENOMEM);
 		error = bp->b_error;