[PATCH 5/9] xfs: add a couple of queries to iterate free extents in the rtbitmap
From: Darrick J. Wong <hidden>
Date: 2017-03-30 15:58:37
Also in:
linux-ext4, linux-fsdevel, linux-xfs
Subsystem:
filesystems (vfs and infrastructure), the rest, xfs filesystem · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds, Carlos Maiolino
From: Darrick J. Wong <redacted> Add _query_range and _query_all functions to the realtime bitmap allocator. These two functions are similar in usage to the btree functions with the same name and will be used for getfsmap and scrub. Signed-off-by: Darrick J. Wong <redacted> Reviewed-by: Brian Foster <redacted> --- fs/xfs/libxfs/xfs_rtbitmap.c | 70 ++++++++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_rtalloc.h | 22 ++++++++++++- 2 files changed, 90 insertions(+), 2 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_rtbitmap.c b/fs/xfs/libxfs/xfs_rtbitmap.c
index ea45584..e47b99e 100644
--- a/fs/xfs/libxfs/xfs_rtbitmap.c
+++ b/fs/xfs/libxfs/xfs_rtbitmap.c@@ -1016,3 +1016,73 @@ xfs_rtfree_extent( } return 0; } + +/* Find all the free records within a given range. */ +int +xfs_rtalloc_query_range( + struct xfs_trans *tp, + struct xfs_rtalloc_rec *low_rec, + struct xfs_rtalloc_rec *high_rec, + xfs_rtalloc_query_range_fn fn, + void *priv) +{ + struct xfs_rtalloc_rec rec; + struct xfs_mount *mp = tp->t_mountp; + xfs_rtblock_t rtstart; + xfs_rtblock_t rtend; + xfs_rtblock_t rem; + int is_free; + int error = 0; + + if (low_rec->ar_startblock > high_rec->ar_startblock) + return -EINVAL; + else if (low_rec->ar_startblock == high_rec->ar_startblock) + return 0; + + /* Iterate the bitmap, looking for discrepancies. */ + rtstart = low_rec->ar_startblock; + rem = high_rec->ar_startblock - rtstart; + while (rem) { + /* Is the first block free? */ + error = xfs_rtcheck_range(mp, tp, rtstart, 1, 1, &rtend, + &is_free); + if (error) + break; + + /* How long does the extent go for? */ + error = xfs_rtfind_forw(mp, tp, rtstart, + high_rec->ar_startblock - 1, &rtend); + if (error) + break; + + if (is_free) { + rec.ar_startblock = rtstart; + rec.ar_blockcount = rtend - rtstart + 1; + + error = fn(tp, &rec, priv); + if (error) + break; + } + + rem -= rtend - rtstart + 1; + rtstart = rtend + 1; + } + + return error; +} + +/* Find all the free records. */ +int +xfs_rtalloc_query_all( + struct xfs_trans *tp, + xfs_rtalloc_query_range_fn fn, + void *priv) +{ + struct xfs_rtalloc_rec keys[2]; + + keys[0].ar_startblock = 0; + keys[1].ar_startblock = tp->t_mountp->m_sb.sb_rblocks; + keys[0].ar_blockcount = keys[1].ar_blockcount = 0; + + return xfs_rtalloc_query_range(tp, &keys[0], &keys[1], fn, priv); +}
diff --git a/fs/xfs/xfs_rtalloc.h b/fs/xfs/xfs_rtalloc.h
index 51dd3c7..f13133e 100644
--- a/fs/xfs/xfs_rtalloc.h
+++ b/fs/xfs/xfs_rtalloc.h@@ -23,6 +23,16 @@ struct xfs_mount; struct xfs_trans; +struct xfs_rtalloc_rec { + xfs_rtblock_t ar_startblock; + xfs_rtblock_t ar_blockcount; +}; + +typedef int (*xfs_rtalloc_query_range_fn)( + struct xfs_trans *tp, + struct xfs_rtalloc_rec *rec, + void *priv); + #ifdef CONFIG_XFS_RT /* * Function prototypes for exported functions.
@@ -118,13 +128,21 @@ int xfs_rtmodify_summary(struct xfs_mount *mp, struct xfs_trans *tp, int log, int xfs_rtfree_range(struct xfs_mount *mp, struct xfs_trans *tp, xfs_rtblock_t start, xfs_extlen_t len, struct xfs_buf **rbpp, xfs_fsblock_t *rsb); -