kevin/linux
1
Fork 0
Code

xfs: create agblock bitmap helper to count the number of set regions

Browse Source 
In the next patch, the rmap btree repair code will need to estimate the
size of the new ondisk rmapbt.  The size is a function of the number of
records that will be written to disk, and the size of the recordset is
the number of observations made while scanning the filesystem plus the
number of OWN_AG records that will be injected into the rmap btree.

OWN_AG rmap records track the free space btrees, the AGFL, and the new
rmap btree itself.  The repair tool uses a bitmap to record the space
used for all four structures, which is why we need a function to count
the number of set regions.

A reviewer requested that this be pulled into a separate patch with its
own justification, so here it is.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Darrick J. Wong 2024-02-22 12:43:37 -08:00
parent 5049ff4d14
commit e4fd1def30
3 changed files with 21 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
fs/xfs/scrub/agb_bitmap.h
View File

@ -65,4 +65,9 @@ int xagb_bitmap_set_btblocks(struct xagb_bitmap *bitmap,
int xagb_bitmap_set_btcur_path(struct xagb_bitmap *bitmap,
struct xfs_btree_cur *cur);
static inline uint32_t xagb_bitmap_count_set_regions(struct xagb_bitmap *b)
{
return xbitmap32_count_set_regions(&b->agbitmap);
}
#endif /* __XFS_SCRUB_AGB_BITMAP_H__ */

14
fs/xfs/scrub/bitmap.c
View File

@ -566,3 +566,17 @@ xbitmap32_test(
*len = bn->bn_start - start;
return false;
}
/* Count the number of set regions in this bitmap. */
uint32_t
xbitmap32_count_set_regions(
struct xbitmap32 *bitmap)
{
struct xbitmap32_node *bn;
uint32_t nr = 0;
for_each_xbitmap32_extent(bn, bitmap)
nr++;
return nr;
}

2
fs/xfs/scrub/bitmap.h
View File

@ -62,4 +62,6 @@ int xbitmap32_walk(struct xbitmap32 *bitmap, xbitmap32_walk_fn fn,
bool xbitmap32_empty(struct xbitmap32 *bitmap);
bool xbitmap32_test(struct xbitmap32 *bitmap, uint32_t start, uint32_t *len);
uint32_t xbitmap32_count_set_regions(struct xbitmap32 *bitmap);
#endif /* __XFS_SCRUB_BITMAP_H__ */