[PATCH 23/67] xfs: extract xfs_da_buf_copy() helper function

Darrick J. Wong
2024-03-26T03:08:50Z

From: Zhang Tianci <zhangtianci.1997@bytedance.com>

Source kernel commit: fd45ddb9dd606b3eaddf26e13f64340636955986

This patch does not modify logic.

xfs_da_buf_copy() will copy one block from src xfs_buf to
dst xfs_buf, and update the block metadata in dst directly.

Signed-off-by: Zhang Tianci <zhangtianci.1997@bytedance.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>
---
libxfs/xfs_attr_leaf.c | 12 +++-----
libxfs/xfs_da_btree.c | 74 +++++++++++++++++++-----------------------------
libxfs/xfs_da_btree.h | 2 +
3 files changed, 36 insertions(+), 52 deletions(-)

diff --git a/libxfs/xfs_attr_leaf.c b/libxfs/xfs_attr_leaf.c
index ed81471ce066..baa168318f91 100644
--- a/libxfs/xfs_attr_leaf.c
+++ b/libxfs/xfs_attr_leaf.c
@@ -1241,14 +1241,10 @@ xfs_attr3_leaf_to_node(
if (error)
goto out;

- /* copy leaf to new buffer, update identifiers */
- xfs_trans_buf_set_type(args->trans, bp2, XFS_BLFT_ATTR_LEAF_BUF);
- bp2->b_ops = bp1->b_ops;
- memcpy(bp2->b_addr, bp1->b_addr, args->geo->blksize);
- if (xfs_has_crc(mp)) {
- struct xfs_da3_blkinfo *hdr3 = bp2->b_addr;
- hdr3->blkno = cpu_to_be64(xfs_buf_daddr(bp2));
- }
+ /*
+ * Copy leaf to new buffer and log it.
+ */
+ xfs_da_buf_copy(bp2, bp1, args->geo->blksize);
xfs_trans_log_buf(args->trans, bp2, 0, args->geo->blksize - 1);

/*
diff --git a/libxfs/xfs_da_btree.c b/libxfs/xfs_da_btree.c
index 3903486d19d2..0779bb6242ca 100644
--- a/libxfs/xfs_da_btree.c
+++ b/libxfs/xfs_da_btree.c
@@ -417,6 +417,25 @@ xfs_da3_node_read_mapped(
return xfs_da3_node_set_type(tp, *bpp);
}

+/*
+ * Copy src directory/attr leaf/node buffer to the dst.
+ * For v5 file systems make sure the right blkno is stamped in.
+ */
+void
+xfs_da_buf_copy(
+ struct xfs_buf *dst,
+ struct xfs_buf *src,
+ size_t size)
+{
+ struct xfs_da3_blkinfo *da3 = dst->b_addr;
+
+ memcpy(dst->b_addr, src->b_addr, size);
+ dst->b_ops = src->b_ops;
+ xfs_trans_buf_copy_type(dst, src);
+ if (xfs_has_crc(dst->b_mount))
+ da3->blkno = cpu_to_be64(xfs_buf_daddr(dst));
+}
+
/*========================================================================
* Routines used for growing the Btree.
*========================================================================*/
@@ -686,12 +705,6 @@ xfs_da3_root_split(
btree = icnodehdr.btree;
size = (int)((char *)&btree[icnodehdr.count] - (char *)oldroot);
level = icnodehdr.level;
-
- /*
- * we are about to copy oldroot to bp, so set up the type
- * of bp while we know exactly what it will be.
- */
- xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DA_NODE_BUF);
} else {
struct xfs_dir3_icleaf_hdr leafhdr;

@@ -703,31 +716,17 @@ xfs_da3_root_split(
size = (int)((char *)&leafhdr.ents[leafhdr.count] -
(char *)leaf);
level = 0;
-
- /*
- * we are about to copy oldroot to bp, so set up the type
- * of bp while we know exactly what it will be.
- */
- xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
}

/*
- * we can copy most of the information in the node from one block to
- * another, but for CRC enabled headers we have to make sure that the
- * block specific identifiers are kept intact. We update the buffer
- * directly for this.
+ * Copy old root to new buffer and log it.
*/
- memcpy(node, oldroot, size);
- if (oldroot->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC) ||
- oldroot->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
- struct xfs_da3_intnode *node3 = (struct xfs_da3_intnode *)node;
-
- node3->hdr.info.blkno = cpu_to_be64(xfs_buf_daddr(bp));
- }
+ xfs_da_buf_copy(bp, blk1->bp, size);
xfs_trans_log_buf(tp, bp, 0, size - 1);

- bp->b_ops = blk1->bp->b_ops;
- xfs_trans_buf_copy_type(bp, blk1->bp);
+ /*
+ * Update blk1 to point to new buffer.
+ */
blk1->bp = bp;
blk1->blkno = blkno;

@@ -1216,21 +1215,14 @@ xfs_da3_root_join(
xfs_da_blkinfo_onlychild_validate(bp->b_addr, oldroothdr.level);

/*
- * This could be copying a leaf back into the root block in the case of
- * there only being a single leaf block left in the tree. Hence we have
- * to update the b_ops pointer as well to match the buffer type change
- * that could occur. For dir3 blocks we also need to update the block
- * number in the buffer header.
+ * Copy child to root buffer and log it.
*/
- memcpy(root_blk->bp->b_addr, bp->b_addr, args->geo->blksize);
- root_blk->bp->b_ops = bp->b_ops;
- xfs_trans_buf_copy_type(root_blk->bp, bp);
- if (oldroothdr.magic == XFS_DA3_NODE_MAGIC) {
- struct xfs_da3_blkinfo *da3 = root_blk->bp->b_addr;
- da3->blkno = cpu_to_be64(xfs_buf_daddr(root_blk->bp));
- }
+ xfs_da_buf_copy(root_blk->bp, bp, args->geo->blksize);
xfs_trans_log_buf(args->trans, root_blk->bp, 0,
args->geo->blksize - 1);
+ /*
+ * Now we can drop the child buffer.
+ */
error = xfs_da_shrink_inode(args, child, bp);
return error;
}
@@ -2312,14 +2304,8 @@ xfs_da3_swap_lastblock(
return error;
/*
* Copy the last block into the dead buffer and log it.
- * On CRC-enabled file systems, also update the stamped in blkno.
*/
- memcpy(dead_buf->b_addr, last_buf->b_addr, args->geo->blksize);
- if (xfs_has_crc(mp)) {
- struct xfs_da3_blkinfo *da3 = dead_buf->b_addr;
-
- da3->blkno = cpu_to_be64(xfs_buf_daddr(dead_buf));
- }
+ xfs_da_buf_copy(dead_buf, last_buf, args->geo->blksize);
xfs_trans_log_buf(tp, dead_buf, 0, args->geo->blksize - 1);
dead_info = dead_buf->b_addr;

diff --git a/libxfs/xfs_da_btree.h b/libxfs/xfs_da_btree.h
index ffa3df5b2893..706baf36e175 100644
--- a/libxfs/xfs_da_btree.h
+++ b/libxfs/xfs_da_btree.h
@@ -219,6 +219,8 @@ int xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno,
const struct xfs_buf_ops *ops);
int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
struct xfs_buf *dead_buf);
+void xfs_da_buf_copy(struct xfs_buf *dst, struct xfs_buf *src,
+ size_t size);

uint xfs_da_hashname(const uint8_t *name_string, int name_length);
enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args,