[PATCH 051/110] xfs: add a xfs_btree_init_ptr_from_cur

Darrick J. Wong
2024-03-26T03:41:44Z

From: Christoph Hellwig <hch@lst.de>

Source kernel commit: f9c18129e57df7b33f4257340840525816481da6

Inode-rooted btrees don't need to initialize the root pointer in the
->init_ptr_from_cur method as the root is found by the
xfs_btree_get_iroot method later. Make ->init_ptr_from_cur option
for inode rooted btrees by providing a helper that does the right
thing for the given btree type and also documents the semantics.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
libxfs/xfs_bmap_btree.c | 9 ---------
libxfs/xfs_btree.c | 27 +++++++++++++++++++++++----
libxfs/xfs_btree.h | 2 ++
libxfs/xfs_btree_staging.c | 1 -
4 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/libxfs/xfs_bmap_btree.c b/libxfs/xfs_bmap_btree.c
index 9f66eee9a598..7fc325fd344c 100644
--- a/libxfs/xfs_bmap_btree.c
+++ b/libxfs/xfs_bmap_btree.c
@@ -368,14 +368,6 @@ xfs_bmbt_init_rec_from_cur(
xfs_bmbt_disk_set_all(&rec->bmbt, &cur->bc_rec.b);
}

-STATIC void
-xfs_bmbt_init_ptr_from_cur(
- struct xfs_btree_cur *cur,
- union xfs_btree_ptr *ptr)
-{
- ptr->l = 0;
-}
-
STATIC int64_t
xfs_bmbt_key_diff(
struct xfs_btree_cur *cur,
@@ -543,7 +535,6 @@ const struct xfs_btree_ops xfs_bmbt_ops = {
.init_key_from_rec = xfs_bmbt_init_key_from_rec,
.init_high_key_from_rec = xfs_bmbt_init_high_key_from_rec,
.init_rec_from_cur = xfs_bmbt_init_rec_from_cur,
- .init_ptr_from_cur = xfs_bmbt_init_ptr_from_cur,
.key_diff = xfs_bmbt_key_diff,
.diff_two_keys = xfs_bmbt_diff_two_keys,
.buf_ops = &xfs_bmbt_buf_ops,
diff --git a/libxfs/xfs_btree.c b/libxfs/xfs_btree.c
index 2511462e3c8f..f59fa54e3ea6 100644
--- a/libxfs/xfs_btree.c
+++ b/libxfs/xfs_btree.c
@@ -1878,6 +1878,25 @@ xfs_lookup_get_search_key(
return xfs_btree_key_addr(cur, keyno, block);
}

+/*
+ * Initialize a pointer to the root block.
+ */
+void
+xfs_btree_init_ptr_from_cur(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr)
+{
+ if (cur->bc_ops->type == XFS_BTREE_TYPE_INODE) {
+ /*
+ * Inode-rooted btrees call xfs_btree_get_iroot to find the root
+ * in xfs_btree_lookup_get_block and don't need a pointer here.
+ */
+ ptr->l = 0;
+ } else {
+ cur->bc_ops->init_ptr_from_cur(cur, ptr);
+ }
+}
+
/*
* Lookup the record. The cursor is made to point to it, based on dir.
* stat is set to 0 if can't find any such record, 1 for success.
@@ -1908,7 +1927,7 @@ xfs_btree_lookup(
keyno = 0;

/* initialise start pointer from cursor */
- cur->bc_ops->init_ptr_from_cur(cur, &ptr);
+ xfs_btree_init_ptr_from_cur(cur, &ptr);
pp = &ptr;

/*
@@ -3118,7 +3137,7 @@ xfs_btree_new_root(
XFS_BTREE_STATS_INC(cur, newroot);

/* initialise our start point from the cursor */
- cur->bc_ops->init_ptr_from_cur(cur, &rptr);
+ xfs_btree_init_ptr_from_cur(cur, &rptr);

/* Allocate the new block. If we can't do it, we're toast. Give up. */
error = xfs_btree_alloc_block(cur, &rptr, &lptr, stat);
@@ -4427,7 +4446,7 @@ xfs_btree_visit_blocks(
struct xfs_btree_block *block = NULL;
int error = 0;

- cur->bc_ops->init_ptr_from_cur(cur, &lptr);
+ xfs_btree_init_ptr_from_cur(cur, &lptr);

/* for each level */
for (level = cur->bc_nlevels - 1; level >= 0; level--) {
@@ -4849,7 +4868,7 @@ xfs_btree_overlapped_query_range(

/* Load the root of the btree. */
level = cur->bc_nlevels - 1;
- cur->bc_ops->init_ptr_from_cur(cur, &ptr);
+ xfs_btree_init_ptr_from_cur(cur, &ptr);
error = xfs_btree_lookup_get_block(cur, level, &ptr, &block);
if (error)
return error;
diff --git a/libxfs/xfs_btree.h b/libxfs/xfs_btree.h
index 07abc56e0395..99194ae94694 100644
--- a/libxfs/xfs_btree.h
+++ b/libxfs/xfs_btree.h
@@ -714,6 +714,8 @@ void xfs_btree_copy_ptrs(struct xfs_btree_cur *cur,
void xfs_btree_copy_keys(struct xfs_btree_cur *cur,
union xfs_btree_key *dst_key,
const union xfs_btree_key *src_key, int numkeys);
+void xfs_btree_init_ptr_from_cur(struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr);

static inline struct xfs_btree_cur *
xfs_btree_alloc_cursor(
diff --git a/libxfs/xfs_btree_staging.c b/libxfs/xfs_btree_staging.c
index 07b43da78752..656bad6cdb77 100644
--- a/libxfs/xfs_btree_staging.c
+++ b/libxfs/xfs_btree_staging.c
@@ -225,7 +225,6 @@ xfs_btree_stage_ifakeroot(
memcpy(nops, cur->bc_ops, sizeof(struct xfs_btree_ops));
nops->alloc_block = xfs_btree_fakeroot_alloc_block;
nops->free_block = xfs_btree_fakeroot_free_block;
- nops->init_ptr_from_cur = xfs_btree_fakeroot_init_ptr_from_cur;
nops->dup_cursor = xfs_btree_fakeroot_dup_cursor;

cur->bc_ino.ifake = ifake;