[GFS2] Tidy up bmap & fix boundary bug [48/70]
From: Steven Whitehouse
Date: Thu Nov 30 2006 - 07:29:54 EST
>From 4cf1ed8144e740de27c6146c25d5d7ea26679cc5 Mon Sep 17 00:00:00 2001
From: Steven Whitehouse <swhiteho@xxxxxxxxxx>
Date: Wed, 15 Nov 2006 15:21:06 -0500
Subject: [PATCH] [GFS2] Tidy up bmap & fix boundary bug
This moves the locking for bmap into the bmap function itself
rather than using a wrapper function. It also fixes a bug where
the boundary flag was set on the wrong bh. Also the flags on
the mapped bh are reset earlier in the function to ensure that
they are 100% correct on the error path.
Signed-off-by: Steven Whitehouse <swhiteho@xxxxxxxxxx>
---
fs/gfs2/bmap.c | 117 ++++++++++++++++++++++++++------------------------------
1 files changed, 54 insertions(+), 63 deletions(-)
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index 06e3447..8240c1f 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -423,12 +423,29 @@ static int lookup_block(struct gfs2_inod
return 0;
}
+static inline void bmap_lock(struct inode *inode, int create)
+{
+ struct gfs2_inode *ip = GFS2_I(inode);
+ if (create)
+ down_write(&ip->i_rw_mutex);
+ else
+ down_read(&ip->i_rw_mutex);
+}
+
+static inline void bmap_unlock(struct inode *inode, int create)
+{
+ struct gfs2_inode *ip = GFS2_I(inode);
+ if (create)
+ up_write(&ip->i_rw_mutex);
+ else
+ up_read(&ip->i_rw_mutex);
+}
+
/**
- * gfs2_block_pointers - Map a block from an inode to a disk block
+ * gfs2_block_map - Map a block from an inode to a disk block
* @inode: The inode
* @lblock: The logical block number
- * @map_bh: The bh to be mapped
- * @mp: metapath to use
+ * @bh_map: The bh to be mapped
*
* Find the block number on the current device which corresponds to an
* inode's block. If the block had to be created, "new" will be set.
@@ -436,8 +453,8 @@ static int lookup_block(struct gfs2_inod
* Returns: errno
*/
-static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create,
- struct buffer_head *bh_map, struct metapath *mp)
+int gfs2_block_map(struct inode *inode, u64 lblock, int create,
+ struct buffer_head *bh_map)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
@@ -451,51 +468,55 @@ static int gfs2_block_pointers(struct in
u64 dblock = 0;
int boundary;
unsigned int maxlen = bh_map->b_size >> inode->i_blkbits;
+ struct metapath mp;
+ u64 size;
BUG_ON(maxlen == 0);
if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip)))
return 0;
+ bmap_lock(inode, create);
+ clear_buffer_mapped(bh_map);
+ clear_buffer_new(bh_map);
+ clear_buffer_boundary(bh_map);
bsize = gfs2_is_dir(ip) ? sdp->sd_jbsize : sdp->sd_sb.sb_bsize;
-
- height = calc_tree_height(ip, (lblock + 1) * bsize);
- if (ip->i_di.di_height < height) {
- if (!create)
- return 0;
-
- error = build_height(inode, height);
- if (error)
- return error;
+ size = (lblock + 1) * bsize;
+
+ if (size > ip->i_di.di_size) {
+ height = calc_tree_height(ip, size);
+ if (ip->i_di.di_height < height) {
+ if (!create)
+ goto out_ok;
+
+ error = build_height(inode, height);
+ if (error)
+ goto out_fail;
+ }
}
- find_metapath(ip, lblock, mp);
+ find_metapath(ip, lblock, &mp);
end_of_metadata = ip->i_di.di_height - 1;
-
error = gfs2_meta_inode_buffer(ip, &bh);
if (error)
- return error;
+ goto out_fail;
for (x = 0; x < end_of_metadata; x++) {
- lookup_block(ip, bh, x, mp, create, &new, &dblock);
+ lookup_block(ip, bh, x, &mp, create, &new, &dblock);
brelse(bh);
if (!dblock)
- return 0;
+ goto out_ok;
error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh);
if (error)
- return error;
+ goto out_fail;
}
- boundary = lookup_block(ip, bh, end_of_metadata, mp, create, &new, &dblock);
- clear_buffer_mapped(bh_map);
- clear_buffer_new(bh_map);
- clear_buffer_boundary(bh_map);
-
+ boundary = lookup_block(ip, bh, end_of_metadata, &mp, create, &new, &dblock);
if (dblock) {
map_bh(bh_map, inode->i_sb, dblock);
if (boundary)
- set_buffer_boundary(bh);
+ set_buffer_boundary(bh_map);
if (new) {
struct buffer_head *dibh;
error = gfs2_meta_inode_buffer(ip, &dibh);
@@ -510,8 +531,8 @@ static int gfs2_block_pointers(struct in
while(--maxlen && !buffer_boundary(bh_map)) {
u64 eblock;
- mp->mp_list[end_of_metadata]++;
- boundary = lookup_block(ip, bh, end_of_metadata, mp, 0, &new, &eblock);
+ mp.mp_list[end_of_metadata]++;
+ boundary = lookup_block(ip, bh, end_of_metadata, &mp, 0, &new, &eblock);
if (eblock != ++dblock)
break;
bh_map->b_size += (1 << inode->i_blkbits);
@@ -521,43 +542,15 @@ static int gfs2_block_pointers(struct in
}
out_brelse:
brelse(bh);
- return 0;
-}
-
-
-static inline void bmap_lock(struct inode *inode, int create)
-{
- struct gfs2_inode *ip = GFS2_I(inode);
- if (create)
- down_write(&ip->i_rw_mutex);
- else
- down_read(&ip->i_rw_mutex);
-}
-
-static inline void bmap_unlock(struct inode *inode, int create)
-{
- struct gfs2_inode *ip = GFS2_I(inode);
- if (create)
- up_write(&ip->i_rw_mutex);
- else
- up_read(&ip->i_rw_mutex);
-}
-
-int gfs2_block_map(struct inode *inode, u64 lblock, int create,
- struct buffer_head *bh)
-{
- struct metapath mp;
- int ret;
-
- bmap_lock(inode, create);
- ret = gfs2_block_pointers(inode, lblock, create, bh, &mp);
+out_ok:
+ error = 0;
+out_fail:
bmap_unlock(inode, create);
- return ret;
+ return error;
}
int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen)
{
- struct metapath mp;
struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 };
int ret;
int create = *new;
@@ -567,9 +560,7 @@ int gfs2_extent_map(struct inode *inode,
BUG_ON(!new);
bh.b_size = 1 << (inode->i_blkbits + 5);
- bmap_lock(inode, create);
- ret = gfs2_block_pointers(inode, lblock, create, &bh, &mp);
- bmap_unlock(inode, create);
+ ret = gfs2_block_map(inode, lblock, create, &bh);
*extlen = bh.b_size >> inode->i_blkbits;
*dblock = bh.b_blocknr;
if (buffer_new(&bh))
--
1.4.1
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/