#include "xfs_ag.h"
#include "xfs_ag_resv.h"
+static struct kmem_cache *xfs_rmapbt_cur_cache;
+
/*
* Reverse map btree.
*
xfs_agblock_t bno;
/* Allocate the new block from the freelist. If we can't, give up. */
- error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_ag.agbp,
+ error = xfs_alloc_get_freelist(pag, cur->bc_tp, cur->bc_ag.agbp,
&bno, 1);
if (error)
return error;
bno, 1);
be32_add_cpu(&agf->agf_rmap_blocks, -1);
xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_RMAP_BLOCKS);
- error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
+ error = xfs_alloc_put_freelist(pag, cur->bc_tp, agbp, NULL, bno, 1);
if (error)
return error;
return cur->bc_mp->m_rmap_mxr[level != 0];
}
+/*
+ * Convert the ondisk record's offset field into the ondisk key's offset field.
+ * Fork and bmbt are significant parts of the rmap record key, but written
+ * status is merely a record attribute.
+ */
+static inline __be64 ondisk_rec_offset_to_key(const union xfs_btree_rec *rec)
+{
+ return rec->rmap.rm_offset & ~cpu_to_be64(XFS_RMAP_OFF_UNWRITTEN);
+}
+
STATIC void
xfs_rmapbt_init_key_from_rec(
union xfs_btree_key *key,
{
key->rmap.rm_startblock = rec->rmap.rm_startblock;
key->rmap.rm_owner = rec->rmap.rm_owner;
- key->rmap.rm_offset = rec->rmap.rm_offset;
+ key->rmap.rm_offset = ondisk_rec_offset_to_key(rec);
}
/*
key->rmap.rm_startblock = rec->rmap.rm_startblock;
be32_add_cpu(&key->rmap.rm_startblock, adj);
key->rmap.rm_owner = rec->rmap.rm_owner;
- key->rmap.rm_offset = rec->rmap.rm_offset;
+ key->rmap.rm_offset = ondisk_rec_offset_to_key(rec);
if (XFS_RMAP_NON_INODE_OWNER(be64_to_cpu(rec->rmap.rm_owner)) ||
XFS_RMAP_IS_BMBT_BLOCK(be64_to_cpu(rec->rmap.rm_offset)))
return;
ptr->s = agf->agf_roots[cur->bc_btnum];
}
+/*
+ * Mask the appropriate parts of the ondisk key field for a key comparison.
+ * Fork and bmbt are significant parts of the rmap record key, but written
+ * status is merely a record attribute.
+ */
+static inline uint64_t offset_keymask(uint64_t offset)
+{
+ return offset & ~XFS_RMAP_OFF_UNWRITTEN;
+}
+
STATIC int64_t
xfs_rmapbt_key_diff(
struct xfs_btree_cur *cur,
else if (y > x)
return -1;
- x = XFS_RMAP_OFF(be64_to_cpu(kp->rm_offset));
- y = rec->rm_offset;
+ x = offset_keymask(be64_to_cpu(kp->rm_offset));
+ y = offset_keymask(xfs_rmap_irec_offset_pack(rec));
if (x > y)
return 1;
else if (y > x)
xfs_rmapbt_diff_two_keys(
struct xfs_btree_cur *cur,
const union xfs_btree_key *k1,
- const union xfs_btree_key *k2)
+ const union xfs_btree_key *k2,
+ const union xfs_btree_key *mask)
{
const struct xfs_rmap_key *kp1 = &k1->rmap;
const struct xfs_rmap_key *kp2 = &k2->rmap;
int64_t d;
__u64 x, y;
+ /* Doesn't make sense to mask off the physical space part */
+ ASSERT(!mask || mask->rmap.rm_startblock);
+
d = (int64_t)be32_to_cpu(kp1->rm_startblock) -
- be32_to_cpu(kp2->rm_startblock);
+ be32_to_cpu(kp2->rm_startblock);
if (d)
return d;
- x = be64_to_cpu(kp1->rm_owner);
- y = be64_to_cpu(kp2->rm_owner);
- if (x > y)
- return 1;
- else if (y > x)
- return -1;
+ if (!mask || mask->rmap.rm_owner) {
+ x = be64_to_cpu(kp1->rm_owner);
+ y = be64_to_cpu(kp2->rm_owner);
+ if (x > y)
+ return 1;
+ else if (y > x)
+ return -1;
+ }
+
+ if (!mask || mask->rmap.rm_offset) {
+ /* Doesn't make sense to allow offset but not owner */
+ ASSERT(!mask || mask->rmap.rm_owner);
+
+ x = offset_keymask(be64_to_cpu(kp1->rm_offset));
+ y = offset_keymask(be64_to_cpu(kp2->rm_offset));
+ if (x > y)
+ return 1;
+ else if (y > x)
+ return -1;
+ }
- x = XFS_RMAP_OFF(be64_to_cpu(kp1->rm_offset));
- y = XFS_RMAP_OFF(be64_to_cpu(kp2->rm_offset));
- if (x > y)
- return 1;
- else if (y > x)
- return -1;
return 0;
}
return fa;
level = be16_to_cpu(block->bb_level);
- if (pag && pag->pagf_init) {
+ if (pag && xfs_perag_initialised_agf(pag)) {
if (level >= pag->pagf_levels[XFS_BTNUM_RMAPi])
return __this_address;
} else if (level >= mp->m_rmap_maxlevels)
return 1;
else if (a > b)
return 0;
- a = XFS_RMAP_OFF(be64_to_cpu(k1->rmap.rm_offset));
- b = XFS_RMAP_OFF(be64_to_cpu(k2->rmap.rm_offset));
+ a = offset_keymask(be64_to_cpu(k1->rmap.rm_offset));
+ b = offset_keymask(be64_to_cpu(k2->rmap.rm_offset));
if (a <= b)
return 1;
return 0;
return 1;
else if (a > b)
return 0;
- a = XFS_RMAP_OFF(be64_to_cpu(r1->rmap.rm_offset));
- b = XFS_RMAP_OFF(be64_to_cpu(r2->rmap.rm_offset));
+ a = offset_keymask(be64_to_cpu(r1->rmap.rm_offset));
+ b = offset_keymask(be64_to_cpu(r2->rmap.rm_offset));
if (a <= b)
return 1;
return 0;
}
+STATIC enum xbtree_key_contig
+xfs_rmapbt_keys_contiguous(
+ struct xfs_btree_cur *cur,
+ const union xfs_btree_key *key1,
+ const union xfs_btree_key *key2,
+ const union xfs_btree_key *mask)
+{
+ ASSERT(!mask || mask->rmap.rm_startblock);
+
+ /*
+ * We only support checking contiguity of the physical space component.
+ * If any callers ever need more specificity than that, they'll have to
+ * implement it here.
+ */
+ ASSERT(!mask || (!mask->rmap.rm_owner && !mask->rmap.rm_offset));
+
+ return xbtree_key_contig(be32_to_cpu(key1->rmap.rm_startblock),
+ be32_to_cpu(key2->rmap.rm_startblock));
+}
+
static const struct xfs_btree_ops xfs_rmapbt_ops = {
.rec_len = sizeof(struct xfs_rmap_rec),
.key_len = 2 * sizeof(struct xfs_rmap_key),
.diff_two_keys = xfs_rmapbt_diff_two_keys,
.keys_inorder = xfs_rmapbt_keys_inorder,
.recs_inorder = xfs_rmapbt_recs_inorder,
+ .keys_contiguous = xfs_rmapbt_keys_contiguous,
};
static struct xfs_btree_cur *
{
struct xfs_btree_cur *cur;
- cur = kmem_cache_zalloc(xfs_btree_cur_zone, GFP_NOFS | __GFP_NOFAIL);
- cur->bc_tp = tp;
- cur->bc_mp = mp;
/* Overlapping btree; 2 keys per pointer. */
- cur->bc_btnum = XFS_BTNUM_RMAP;
+ cur = xfs_btree_alloc_cursor(mp, tp, XFS_BTNUM_RMAP,
+ mp->m_rmap_maxlevels, xfs_rmapbt_cur_cache);
cur->bc_flags = XFS_BTREE_CRC_BLOCKS | XFS_BTREE_OVERLAPPING;
- cur->bc_blocklog = mp->m_sb.sb_blocklog;
cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_rmap_2);
cur->bc_ops = &xfs_rmapbt_ops;
- /* take a reference for the cursor */
- atomic_inc(&pag->pag_ref);
- cur->bc_ag.pag = pag;
-
+ cur->bc_ag.pag = xfs_perag_hold(pag);
return cur;
}
xfs_btree_commit_afakeroot(cur, tp, agbp, &xfs_rmapbt_ops);
}
+/* Calculate number of records in a reverse mapping btree block. */
+static inline unsigned int
+xfs_rmapbt_block_maxrecs(
+ unsigned int blocklen,
+ bool leaf)
+{
+ if (leaf)
+ return blocklen / sizeof(struct xfs_rmap_rec);
+ return blocklen /
+ (2 * sizeof(struct xfs_rmap_key) + sizeof(xfs_rmap_ptr_t));
+}
+
/*
* Calculate number of records in an rmap btree block.
*/
int leaf)
{
blocklen -= XFS_RMAP_BLOCK_LEN;
+ return xfs_rmapbt_block_maxrecs(blocklen, leaf);
+}
- if (leaf)
- return blocklen / sizeof(struct xfs_rmap_rec);
- return blocklen /
- (2 * sizeof(struct xfs_rmap_key) + sizeof(xfs_rmap_ptr_t));
+/* Compute the max possible height for reverse mapping btrees. */
+unsigned int
+xfs_rmapbt_maxlevels_ondisk(void)
+{
+ unsigned int minrecs[2];
+ unsigned int blocklen;
+
+ blocklen = XFS_MIN_CRC_BLOCKSIZE - XFS_BTREE_SBLOCK_CRC_LEN;
+
+ minrecs[0] = xfs_rmapbt_block_maxrecs(blocklen, true) / 2;
+ minrecs[1] = xfs_rmapbt_block_maxrecs(blocklen, false) / 2;
+
+ /*
+ * Compute the asymptotic maxlevels for an rmapbt on any reflink fs.
+ *
+ * On a reflink filesystem, each AG block can have up to 2^32 (per the
+ * refcount record format) owners, which means that theoretically we
+ * could face up to 2^64 rmap records. However, we're likely to run
+ * out of blocks in the AG long before that happens, which means that
+ * we must compute the max height based on what the btree will look
+ * like if it consumes almost all the blocks in the AG due to maximal
+ * sharing factor.
+ */
+ return xfs_btree_space_to_height(minrecs, XFS_MAX_CRC_AG_BLOCKS);
}
/* Compute the maximum height of an rmap btree. */
xfs_rmapbt_compute_maxlevels(
struct xfs_mount *mp)
{
- /*
- * On a non-reflink filesystem, the maximum number of rmap
- * records is the number of blocks in the AG, hence the max
- * rmapbt height is log_$maxrecs($agblocks). However, with
- * reflink each AG block can have up to 2^32 (per the refcount
- * record format) owners, which means that theoretically we
- * could face up to 2^64 rmap records.
- *
- * That effectively means that the max rmapbt height must be
- * XFS_BTREE_MAXLEVELS. "Fortunately" we'll run out of AG
- * blocks to feed the rmapbt long before the rmapbt reaches
- * maximum height. The reflink code uses ag_resv_critical to
- * disallow reflinking when less than 10% of the per-AG metadata
- * block reservation since the fallback is a regular file copy.
- */
- if (xfs_has_reflink(mp))
- mp->m_rmap_maxlevels = XFS_BTREE_MAXLEVELS;
- else
+ if (!xfs_has_rmapbt(mp)) {
+ mp->m_rmap_maxlevels = 0;
+ return;
+ }
+
+ if (xfs_has_reflink(mp)) {
+ /*
+ * Compute the asymptotic maxlevels for an rmap btree on a
+ * filesystem that supports reflink.
+ *
+ * On a reflink filesystem, each AG block can have up to 2^32
+ * (per the refcount record format) owners, which means that
+ * theoretically we could face up to 2^64 rmap records.
+ * However, we're likely to run out of blocks in the AG long
+ * before that happens, which means that we must compute the
+ * max height based on what the btree will look like if it
+ * consumes almost all the blocks in the AG due to maximal
+ * sharing factor.
+ */
+ mp->m_rmap_maxlevels = xfs_btree_space_to_height(mp->m_rmap_mnr,
+ mp->m_sb.sb_agblocks);
+ } else {
+ /*
+ * If there's no block sharing, compute the maximum rmapbt
+ * height assuming one rmap record per AG block.
+ */
mp->m_rmap_maxlevels = xfs_btree_compute_maxlevels(
mp->m_rmap_mnr, mp->m_sb.sb_agblocks);
+ }
+ ASSERT(mp->m_rmap_maxlevels <= xfs_rmapbt_maxlevels_ondisk());
}
/* Calculate the refcount btree size for some records. */
if (!xfs_has_rmapbt(mp))
return 0;
- error = xfs_alloc_read_agf(mp, tp, pag->pag_agno, 0, &agbp);
+ error = xfs_alloc_read_agf(pag, tp, 0, &agbp);
if (error)
return error;
* never be available for the kinds of things that would require btree
* expansion. We therefore can pretend the space isn't there.
*/
- if (mp->m_sb.sb_logstart &&
- XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart) == pag->pag_agno)
+ if (xfs_ag_contains_log(mp, pag->pag_agno))
agblocks -= mp->m_sb.sb_logblocks;
/* Reserve 1% of the AG or enough for 1 block per record. */
return error;
}
+
+int __init
+xfs_rmapbt_init_cur_cache(void)
+{
+ xfs_rmapbt_cur_cache = kmem_cache_create("xfs_rmapbt_cur",
+ xfs_btree_cur_sizeof(xfs_rmapbt_maxlevels_ondisk()),
+ 0, 0, NULL);
+
+ if (!xfs_rmapbt_cur_cache)
+ return -ENOMEM;
+ return 0;
+}
+
+void
+xfs_rmapbt_destroy_cur_cache(void)
+{
+ kmem_cache_destroy(xfs_rmapbt_cur_cache);
+ xfs_rmapbt_cur_cache = NULL;
+}