xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

xfs: implement deferred bmbt map/unmap operations

Browse Source 
Implement deferred versions of the inode block map/unmap functions.
These will be used in subsequent patches to make reflink operations
atomic.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Darrick J. Wong
2016-10-03 09:11:28 -07:00
parent 4847acf868
commit 9f3afb57d5
9 changed files with 393 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

143
fs/xfs/libxfs/xfs_bmap.c
View File

@@ -6062,3 +6062,146 @@ out:
xfs_trans_cancel(tp);
return error;
}
/* Deferred mapping is only for real extents in the data fork. */
static bool
xfs_bmap_is_update_needed(
struct xfs_bmbt_irec *bmap)
{
return bmap->br_startblock != HOLESTARTBLOCK &&
bmap->br_startblock != DELAYSTARTBLOCK;
}
/* Record a bmap intent. */
static int
__xfs_bmap_add(
struct xfs_mount *mp,
struct xfs_defer_ops *dfops,
enum xfs_bmap_intent_type type,
struct xfs_inode *ip,
int whichfork,
struct xfs_bmbt_irec *bmap)
{
int error;
struct xfs_bmap_intent *bi;
trace_xfs_bmap_defer(mp,
XFS_FSB_TO_AGNO(mp, bmap->br_startblock),
type,
XFS_FSB_TO_AGBNO(mp, bmap->br_startblock),
ip->i_ino, whichfork,
bmap->br_startoff,
bmap->br_blockcount,
bmap->br_state);
bi = kmem_alloc(sizeof(struct xfs_bmap_intent), KM_SLEEP | KM_NOFS);
INIT_LIST_HEAD(&bi->bi_list);
bi->bi_type = type;
bi->bi_owner = ip;
bi->bi_whichfork = whichfork;
bi->bi_bmap = *bmap;
error = xfs_defer_join(dfops, bi->bi_owner);
if (error) {
kmem_free(bi);
return error;
}
xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_BMAP, &bi->bi_list);
return 0;
}
/* Map an extent into a file. */
int
xfs_bmap_map_extent(
struct xfs_mount *mp,
struct xfs_defer_ops *dfops,
struct xfs_inode *ip,
struct xfs_bmbt_irec *PREV)
{
if (!xfs_bmap_is_update_needed(PREV))
return 0;
return __xfs_bmap_add(mp, dfops, XFS_BMAP_MAP, ip,
XFS_DATA_FORK, PREV);
}
/* Unmap an extent out of a file. */
int
xfs_bmap_unmap_extent(
struct xfs_mount *mp,
struct xfs_defer_ops *dfops,
struct xfs_inode *ip,
struct xfs_bmbt_irec *PREV)
{
if (!xfs_bmap_is_update_needed(PREV))
return 0;
return __xfs_bmap_add(mp, dfops, XFS_BMAP_UNMAP, ip,
XFS_DATA_FORK, PREV);
}
/*
* Process one of the deferred bmap operations. We pass back the
* btree cursor to maintain our lock on the bmapbt between calls.
*/
int
xfs_bmap_finish_one(
struct xfs_trans *tp,
struct xfs_defer_ops *dfops,
struct xfs_inode *ip,
enum xfs_bmap_intent_type type,
int whichfork,
xfs_fileoff_t startoff,
xfs_fsblock_t startblock,
xfs_filblks_t blockcount,
xfs_exntst_t state)
{
struct xfs_bmbt_irec bmap;
int nimaps = 1;
xfs_fsblock_t firstfsb;
int flags = XFS_BMAPI_REMAP;
int done;
int error = 0;
bmap.br_startblock = startblock;
bmap.br_startoff = startoff;
bmap.br_blockcount = blockcount;
bmap.br_state = state;
trace_xfs_bmap_deferred(tp->t_mountp,
XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type,
XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
ip->i_ino, whichfork, startoff, blockcount, state);
if (whichfork != XFS_DATA_FORK && whichfork != XFS_ATTR_FORK)
return -EFSCORRUPTED;
if (whichfork == XFS_ATTR_FORK)
flags |= XFS_BMAPI_ATTRFORK;
if (XFS_TEST_ERROR(false, tp->t_mountp,
XFS_ERRTAG_BMAP_FINISH_ONE,
XFS_RANDOM_BMAP_FINISH_ONE))
return -EIO;
switch (type) {
case XFS_BMAP_MAP:
firstfsb = bmap.br_startblock;
error = xfs_bmapi_write(tp, ip, bmap.br_startoff,
bmap.br_blockcount, flags, &firstfsb,
bmap.br_blockcount, &bmap, &nimaps,
dfops);
break;
case XFS_BMAP_UNMAP:
error = xfs_bunmapi(tp, ip, bmap.br_startoff,
bmap.br_blockcount, flags, 1, &firstfsb,
dfops, &done);
ASSERT(done);
break;
default:
ASSERT(0);
error = -EFSCORRUPTED;
}
return error;
}