[PATCH 34/56] xfs: add realtime refcount btree operations

Darrick J. Wong
2025-02-06T22:44:00Z

Source kernel commit: 1a6f88ea538db9b3d8aef86112894e7e6d098287

Implement the generic btree operations needed to manipulate rtrefcount
btree blocks. This is different from the regular refcountbt in that we
allocate space from the filesystem at large, and are neither constrained
to the free space nor any particular AG.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
libxfs/xfs_rtrefcount_btree.c | 148 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 148 insertions(+)

diff --git a/libxfs/xfs_rtrefcount_btree.c b/libxfs/xfs_rtrefcount_btree.c
index d92ef06b04a73e..ea05b1a48eab62 100644
--- a/libxfs/xfs_rtrefcount_btree.c
+++ b/libxfs/xfs_rtrefcount_btree.c
@@ -19,6 +19,7 @@
#include "xfs_btree.h"
#include "xfs_btree_staging.h"
#include "xfs_rtrefcount_btree.h"
+#include "xfs_refcount.h"
#include "xfs_trace.h"
#include "xfs_cksum.h"
#include "xfs_rtgroup.h"
@@ -43,6 +44,106 @@ xfs_rtrefcountbt_dup_cursor(
return xfs_rtrefcountbt_init_cursor(cur->bc_tp, to_rtg(cur->bc_group));
}

+STATIC int
+xfs_rtrefcountbt_get_minrecs(
+ struct xfs_btree_cur *cur,
+ int level)
+{
+ if (level == cur->bc_nlevels - 1) {
+ struct xfs_ifork *ifp = xfs_btree_ifork_ptr(cur);
+
+ return xfs_rtrefcountbt_maxrecs(cur->bc_mp, ifp->if_broot_bytes,
+ level == 0) / 2;
+ }
+
+ return cur->bc_mp->m_rtrefc_mnr[level != 0];
+}
+
+STATIC int
+xfs_rtrefcountbt_get_maxrecs(
+ struct xfs_btree_cur *cur,
+ int level)
+{
+ if (level == cur->bc_nlevels - 1) {
+ struct xfs_ifork *ifp = xfs_btree_ifork_ptr(cur);
+
+ return xfs_rtrefcountbt_maxrecs(cur->bc_mp, ifp->if_broot_bytes,
+ level == 0);
+ }
+
+ return cur->bc_mp->m_rtrefc_mxr[level != 0];
+}
+
+STATIC void
+xfs_rtrefcountbt_init_key_from_rec(
+ union xfs_btree_key *key,
+ const union xfs_btree_rec *rec)
+{
+ key->refc.rc_startblock = rec->refc.rc_startblock;
+}
+
+STATIC void
+xfs_rtrefcountbt_init_high_key_from_rec(
+ union xfs_btree_key *key,
+ const union xfs_btree_rec *rec)
+{
+ __u32 x;
+
+ x = be32_to_cpu(rec->refc.rc_startblock);
+ x += be32_to_cpu(rec->refc.rc_blockcount) - 1;
+ key->refc.rc_startblock = cpu_to_be32(x);
+}
+
+STATIC void
+xfs_rtrefcountbt_init_rec_from_cur(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_rec *rec)
+{
+ const struct xfs_refcount_irec *irec = &cur->bc_rec.rc;
+ uint32_t start;
+
+ start = xfs_refcount_encode_startblock(irec->rc_startblock,
+ irec->rc_domain);
+ rec->refc.rc_startblock = cpu_to_be32(start);
+ rec->refc.rc_blockcount = cpu_to_be32(cur->bc_rec.rc.rc_blockcount);
+ rec->refc.rc_refcount = cpu_to_be32(cur->bc_rec.rc.rc_refcount);
+}
+
+STATIC void
+xfs_rtrefcountbt_init_ptr_from_cur(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr)
+{
+ ptr->l = 0;
+}
+
+STATIC int64_t
+xfs_rtrefcountbt_key_diff(
+ struct xfs_btree_cur *cur,
+ const union xfs_btree_key *key)
+{
+ const struct xfs_refcount_key *kp = &key->refc;
+ const struct xfs_refcount_irec *irec = &cur->bc_rec.rc;
+ uint32_t start;
+
+ start = xfs_refcount_encode_startblock(irec->rc_startblock,
+ irec->rc_domain);
+ return (int64_t)be32_to_cpu(kp->rc_startblock) - start;
+}
+
+STATIC int64_t
+xfs_rtrefcountbt_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 *mask)
+{
+ ASSERT(!mask || mask->refc.rc_startblock);
+
+ return (int64_t)be32_to_cpu(k1->refc.rc_startblock) -
+ be32_to_cpu(k2->refc.rc_startblock);
+}
+
static xfs_failaddr_t
xfs_rtrefcountbt_verify(
struct xfs_buf *bp)
@@ -109,6 +210,40 @@ const struct xfs_buf_ops xfs_rtrefcountbt_buf_ops = {
.verify_struct = xfs_rtrefcountbt_verify,
};

+STATIC int
+xfs_rtrefcountbt_keys_inorder(
+ struct xfs_btree_cur *cur,
+ const union xfs_btree_key *k1,
+ const union xfs_btree_key *k2)
+{
+ return be32_to_cpu(k1->refc.rc_startblock) <
+ be32_to_cpu(k2->refc.rc_startblock);
+}
+
+STATIC int
+xfs_rtrefcountbt_recs_inorder(
+ struct xfs_btree_cur *cur,
+ const union xfs_btree_rec *r1,
+ const union xfs_btree_rec *r2)
+{
+ return be32_to_cpu(r1->refc.rc_startblock) +
+ be32_to_cpu(r1->refc.rc_blockcount) <=
+ be32_to_cpu(r2->refc.rc_startblock);
+}
+
+STATIC enum xbtree_key_contig
+xfs_rtrefcountbt_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->refc.rc_startblock);
+
+ return xbtree_key_contig(be32_to_cpu(key1->refc.rc_startblock),
+ be32_to_cpu(key2->refc.rc_startblock));
+}
+
const struct xfs_btree_ops xfs_rtrefcountbt_ops = {
.name = "rtrefcount",
.type = XFS_BTREE_TYPE_INODE,
@@ -122,7 +257,20 @@ const struct xfs_btree_ops xfs_rtrefcountbt_ops = {
.statoff = XFS_STATS_CALC_INDEX(xs_rtrefcbt_2),

.dup_cursor = xfs_rtrefcountbt_dup_cursor,
+ .alloc_block = xfs_btree_alloc_metafile_block,
+ .free_block = xfs_btree_free_metafile_block,
+ .get_minrecs = xfs_rtrefcountbt_get_minrecs,
+ .get_maxrecs = xfs_rtrefcountbt_get_maxrecs,
+ .init_key_from_rec = xfs_rtrefcountbt_init_key_from_rec,
+ .init_high_key_from_rec = xfs_rtrefcountbt_init_high_key_from_rec,
+ .init_rec_from_cur = xfs_rtrefcountbt_init_rec_from_cur,
+ .init_ptr_from_cur = xfs_rtrefcountbt_init_ptr_from_cur,
+ .key_diff = xfs_rtrefcountbt_key_diff,
.buf_ops = &xfs_rtrefcountbt_buf_ops,
+ .diff_two_keys = xfs_rtrefcountbt_diff_two_keys,
+ .keys_inorder = xfs_rtrefcountbt_keys_inorder,
+ .recs_inorder = xfs_rtrefcountbt_recs_inorder,
+ .keys_contiguous = xfs_rtrefcountbt_keys_contiguous,
};

/* Allocate a new rt refcount btree cursor. */