gfs2: Clarify gfs2_block_map

Add a comment about the logical block size for directories.  Rename
"bsize" in gfs2_block_map to "factor".  Fix a typo in the description of
metaptr1.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
This commit is contained in:
Andreas Gruenbacher 2017-09-22 07:39:54 -05:00 committed by Bob Peterson
parent 10201655b0
commit 20cdc1931e

View File

@ -248,7 +248,7 @@ static inline unsigned int metapath_branch_start(const struct metapath *mp)
}
/**
* metaptr1 - Return the first possible metadata pointer in a metaath buffer
* metaptr1 - Return the first possible metadata pointer in a metapath buffer
* @height: The metadata height (0 = dinode)
* @mp: The metapath
*/
@ -659,7 +659,7 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
unsigned int bsize = sdp->sd_sb.sb_bsize;
unsigned int factor = sdp->sd_sb.sb_bsize;
const size_t maxlen = bh_map->b_size >> inode->i_blkbits;
const u64 *arr = sdp->sd_heightsize;
__be64 *ptr;
@ -679,8 +679,14 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
clear_buffer_new(bh_map);
clear_buffer_boundary(bh_map);
trace_gfs2_bmap(ip, bh_map, lblock, create, 1);
/*
* Directory data blocks have a struct gfs2_meta_header header, so the
* remaining size is smaller than the filesystem block size. Logical
* block numbers for directories are in units of this remaining size!
*/
if (gfs2_is_dir(ip)) {
bsize = sdp->sd_jbsize;
factor = sdp->sd_jbsize;
arr = sdp->sd_jheightsize;
}
@ -689,7 +695,7 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
goto out;
height = ip->i_height;
size = (lblock + 1) * bsize;
size = (lblock + 1) * factor;
while (size > arr[height])
height++;
find_metapath(sdp, lblock, &mp, height);