mirrors/scoutfs
1
0
Fork 0
mirror of https://github.com/versity/scoutfs.git synced 2026-02-07 11:10:44 +00:00
Code Issues Packages Projects Releases Wiki Activity

scoutfs: merge offline extents

Browse Source 
Offline extents weren't being merged because they all had their physical
blkno set to 0 and all the extent calculations didn't treat them
specially.  They would only merge if the physical blocks of two extent
were contiguous.  Instead of special casing offline extents everywhere
we store them with a physical blkno set to the logical blk_off.  This
lets all the current extent calculations work as expected.

Signed-off-by: Zach Brown <zab@versity.com>
This commit is contained in:
Zach Brown
2017-08-01 14:40:18 -07:00
committed by Zach Brown
parent 7cc09761f5
commit 07bbc418c3
1 changed files with 19 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
kmod/src/data.c
View File

@@ -59,6 +59,12 @@
* ensures that data is persistent before the metadata that references
* it is visible.
*
* Files can have offline extents. They have no allocated file data but
* the offline status represents file data that can be recalled through
* staging. While offline the extents have their physical blkno set to
* the logical blk_off so that all the usual block extent calculations
* still hold. It's mapped back to phys == 0 for fiemap.
*
* Weirdly, the extents are indexed by the *final* logical block and
* blkno of the extent. This lets us search for neighbouring previous
* extents with a _next() call and avoids having to implement item
@@ -388,7 +394,7 @@ static int insert_extent(struct super_block *sb,
trace_printk("inserting "EXTF"\n", EXTA(caller_ins));
/* find previous that might be adjacent */
ret = try_merge(sb, &ins, -1, &left, arg, type);
ret = try_merge(sb, &ins, -1, &left, arg, type) ?:
try_merge(sb, &ins, 1, &right, arg, type);
if (ret < 0)
goto out;
@@ -561,9 +567,9 @@ int scoutfs_data_truncate_items(struct super_block *sb, u64 ino, u64 iblock,
load_extent(&found, &key);
trace_printk("found "EXTF"\n", EXTA(&found));
/* XXX corruption: offline and allocation are exclusive */
if (!!found.blkno ==
!!(found.flags & SCOUTFS_FILE_EXTENT_OFFLINE)) {
/* XXX corruption: offline has phys == log */
if ((found.flags & SCOUTFS_FILE_EXTENT_OFFLINE) &&
found.blkno != found.blk_off) {
ret = -EIO;
break;
}
@@ -618,9 +624,9 @@ int scoutfs_data_truncate_items(struct super_block *sb, u64 ino, u64 iblock,
/* maybe add new file extents with the offline flag set */
if (offline) {
ofl = ext;
ofl.blkno = 0;
ofl.blkno = ofl.blk_off;
ofl.flags = SCOUTFS_FILE_EXTENT_OFFLINE;
ret = insert_extent(sb, &ofl, sbi->node_id,
ret = insert_extent(sb, &ofl, ino,
SCOUTFS_FILE_EXTENT_TYPE);
if (ret)
break;
@@ -913,7 +919,7 @@ retry:
/* remove old offline block if we're staging */
if (was_offline) {
ofl.blk_off = iblock;
ofl.blkno = 0;
ofl.blkno = iblock;
ofl.blocks = 1;
ofl.flags = SCOUTFS_FILE_EXTENT_OFFLINE;
ret = remove_extent(sb, &ofl, ino, SCOUTFS_FILE_EXTENT_TYPE);
@@ -1219,8 +1225,12 @@ int scoutfs_data_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
logical = ext.blk_off << SCOUTFS_BLOCK_SHIFT;
phys = ext.blkno << SCOUTFS_BLOCK_SHIFT;
size = ext.blocks << SCOUTFS_BLOCK_SHIFT;
flags = ext.flags & SCOUTFS_FILE_EXTENT_OFFLINE ?
FIEMAP_EXTENT_UNKNOWN : 0;
flags = 0;
if (ext.flags & SCOUTFS_FILE_EXTENT_OFFLINE) {
phys = 0;
flags = FIEMAP_EXTENT_UNKNOWN;
}
blk_off = ext.blk_off + ext.blocks;
}