[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@redhat.com>
This commit is contained in:
Steven Whitehouse 2006-11-15 15:21:06 -05:00
parent ab923031ce
commit 4cf1ed8144

View file

@ -423,108 +423,6 @@ static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh,
return 0;
}
/**
* gfs2_block_pointers - 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
*
* 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.
*
* Returns: errno
*/
static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create,
struct buffer_head *bh_map, struct metapath *mp)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
struct buffer_head *bh;
unsigned int bsize;
unsigned int height;
unsigned int end_of_metadata;
unsigned int x;
int error = 0;
int new = 0;
u64 dblock = 0;
int boundary;
unsigned int maxlen = bh_map->b_size >> inode->i_blkbits;
BUG_ON(maxlen == 0);
if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip)))
return 0;
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;
}
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;
for (x = 0; x < end_of_metadata; x++) {
lookup_block(ip, bh, x, mp, create, &new, &dblock);
brelse(bh);
if (!dblock)
return 0;
error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh);
if (error)
return error;
}
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);
if (dblock) {
map_bh(bh_map, inode->i_sb, dblock);
if (boundary)
set_buffer_boundary(bh);
if (new) {
struct buffer_head *dibh;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (!error) {
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
}
set_buffer_new(bh_map);
goto out_brelse;
}
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);
if (eblock != ++dblock)
break;
bh_map->b_size += (1 << inode->i_blkbits);
if (boundary)
set_buffer_boundary(bh_map);
}
}
out_brelse:
brelse(bh);
return 0;
}
static inline void bmap_lock(struct inode *inode, int create)
{
struct gfs2_inode *ip = GFS2_I(inode);
@ -543,21 +441,116 @@ static inline void bmap_unlock(struct inode *inode, int create)
up_read(&ip->i_rw_mutex);
}
/**
* gfs2_block_map - Map a block from an inode to a disk block
* @inode: The inode
* @lblock: The logical block number
* @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.
*
* Returns: errno
*/
int gfs2_block_map(struct inode *inode, u64 lblock, int create,
struct buffer_head *bh)
struct buffer_head *bh_map)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
struct buffer_head *bh;
unsigned int bsize;
unsigned int height;
unsigned int end_of_metadata;
unsigned int x;
int error = 0;
int new = 0;
u64 dblock = 0;
int boundary;
unsigned int maxlen = bh_map->b_size >> inode->i_blkbits;
struct metapath mp;
int ret;
u64 size;
BUG_ON(maxlen == 0);
if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip)))
return 0;
bmap_lock(inode, create);
ret = gfs2_block_pointers(inode, lblock, create, bh, &mp);
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;
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);
end_of_metadata = ip->i_di.di_height - 1;
error = gfs2_meta_inode_buffer(ip, &bh);
if (error)
goto out_fail;
for (x = 0; x < end_of_metadata; x++) {
lookup_block(ip, bh, x, &mp, create, &new, &dblock);
brelse(bh);
if (!dblock)
goto out_ok;
error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh);
if (error)
goto out_fail;
}
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_map);
if (new) {
struct buffer_head *dibh;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (!error) {
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
}
set_buffer_new(bh_map);
goto out_brelse;
}
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);
if (eblock != ++dblock)
break;
bh_map->b_size += (1 << inode->i_blkbits);
if (boundary)
set_buffer_boundary(bh_map);
}
}
out_brelse:
brelse(bh);
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, u64 lblock, int *new, u64 *dblock, unsi
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))