gfs2: Further iomap cleanups
In gfs2_iomap_alloc, set the type of newly allocated extents to
IOMAP_MAPPED so that iomap_to_bh will set the bh states correctly:
otherwise, the bhs would not be marked as mapped, confusing
__mpage_writepage. This means that we need to check for the IOMAP_F_NEW
flag in fallocate_chunk now.
Further clean up gfs2_iomap_get and implement gfs2_stuffed_iomap here
directly. For reads beyond the end of the file, return holes instead of
failing with -ENOENT so that we can get rid of that special case in
gfs2_block_map.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index ed66997..33ee933 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -750,6 +750,7 @@ static int gfs2_iomap_alloc(struct inode *inode, struct iomap *iomap,
}
} while (iomap->addr == IOMAP_NULL_ADDR);
+ iomap->type = IOMAP_MAPPED;
iomap->length = (u64)dblks << inode->i_blkbits;
ip->i_height = mp->mp_fheight;
gfs2_add_inode_blocks(&ip->i_inode, alloced);
@@ -759,17 +760,6 @@ static int gfs2_iomap_alloc(struct inode *inode, struct iomap *iomap,
return ret;
}
-static void gfs2_stuffed_iomap(struct inode *inode, struct iomap *iomap)
-{
- struct gfs2_inode *ip = GFS2_I(inode);
-
- iomap->addr = (ip->i_no_addr << inode->i_blkbits) +
- sizeof(struct gfs2_dinode);
- iomap->offset = 0;
- iomap->length = i_size_read(inode);
- iomap->type = IOMAP_INLINE;
-}
-
#define IOMAP_F_GFS2_BOUNDARY IOMAP_F_PRIVATE
/**
@@ -789,37 +779,61 @@ static int gfs2_iomap_get(struct inode *inode, loff_t pos, loff_t length,
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
+ loff_t size = i_size_read(inode);
__be64 *ptr;
sector_t lblock;
sector_t lblock_stop;
int ret;
int eob;
u64 len;
- struct buffer_head *bh;
+ struct buffer_head *dibh = NULL, *bh;
u8 height;
if (!length)
return -EINVAL;
+ down_read(&ip->i_rw_mutex);
+
+ ret = gfs2_meta_inode_buffer(ip, &dibh);
+ if (ret)
+ goto unlock;
+
if (gfs2_is_stuffed(ip)) {
- if (flags & IOMAP_REPORT) {
- if (pos >= i_size_read(inode))
- return -ENOENT;
- gfs2_stuffed_iomap(inode, iomap);
- return 0;
+ if (flags & IOMAP_WRITE) {
+ loff_t max_size = gfs2_max_stuffed_size(ip);
+
+ if (pos + length > max_size)
+ goto unstuff;
+ iomap->length = max_size;
+ } else {
+ if (pos >= size) {
+ if (flags & IOMAP_REPORT) {
+ ret = -ENOENT;
+ goto unlock;
+ } else {
+ /* report a hole */
+ iomap->offset = pos;
+ iomap->length = length;
+ goto do_alloc;
+ }
+ }
+ iomap->length = size;
}
- BUG_ON(!(flags & IOMAP_WRITE));
+ iomap->addr = (ip->i_no_addr << inode->i_blkbits) +
+ sizeof(struct gfs2_dinode);
+ iomap->type = IOMAP_INLINE;
+ goto out;
}
+
+unstuff:
lblock = pos >> inode->i_blkbits;
iomap->offset = lblock << inode->i_blkbits;
lblock_stop = (pos + length - 1) >> inode->i_blkbits;
len = lblock_stop - lblock + 1;
+ iomap->length = len << inode->i_blkbits;
- down_read(&ip->i_rw_mutex);
-
- ret = gfs2_meta_inode_buffer(ip, &mp->mp_bh[0]);
- if (ret)
- goto unlock;
+ get_bh(dibh);
+ mp->mp_bh[0] = dibh;
height = ip->i_height;
while ((lblock + 1) * sdp->sd_sb.sb_bsize > sdp->sd_heightsize[height])
@@ -853,21 +867,23 @@ static int gfs2_iomap_get(struct inode *inode, loff_t pos, loff_t length,
iomap->bdev = inode->i_sb->s_bdev;
unlock:
up_read(&ip->i_rw_mutex);
+ if (dibh)
+ brelse(dibh);
return ret;
do_alloc:
iomap->addr = IOMAP_NULL_ADDR;
- iomap->length = len << inode->i_blkbits;
iomap->type = IOMAP_HOLE;
- iomap->flags = 0;
if (flags & IOMAP_REPORT) {
- loff_t size = i_size_read(inode);
if (pos >= size)
ret = -ENOENT;
else if (height == ip->i_height)
ret = gfs2_hole_size(inode, lblock, len, mp, iomap);
else
iomap->length = size - pos;
+ } else if (!(flags & IOMAP_WRITE)) {
+ if (pos < size && height == ip->i_height)
+ ret = gfs2_hole_size(inode, lblock, len, mp, iomap);
}
goto out;
}
@@ -941,12 +957,6 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
} else {
ret = gfs2_iomap_get(inode, pos, length, 0, &iomap, &mp);
release_metapath(&mp);
-
- /* Return unmapped buffer beyond the end of file. */
- if (ret == -ENOENT) {
- ret = 0;
- goto out;
- }
}
if (ret)
goto out;
