Re: [PATCH 03/46] xfs: refactor btree node scrubbing

Darrick J. Wong
2019-11-07T22:44:02Z

On Thu, Nov 07, 2019 at 07:23:27PM +0100, Christoph Hellwig wrote:
> Break up xchk_da_btree_entry and handle looking up leaf node entries
> in the attr / dir callbacks, so that only the generic node handling
> is left in the common core code. Note that the checks for the crc
> enabled blocks are removed, as the scrubbing code already remaps the
> magic numbers earlier.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> fs/xfs/scrub/attr.c | 11 +++++-----
> fs/xfs/scrub/dabtree.c | 48 ++++++++++--------------------------------
> fs/xfs/scrub/dabtree.h | 3 +--
> fs/xfs/scrub/dir.c | 12 ++++++++---
> 4 files changed, 27 insertions(+), 47 deletions(-)
>
> diff --git a/fs/xfs/scrub/attr.c b/fs/xfs/scrub/attr.c
> index 0edc7f8eb96e..d9f0dd444b80 100644
> --- a/fs/xfs/scrub/attr.c
> +++ b/fs/xfs/scrub/attr.c
> @@ -398,15 +398,14 @@ xchk_xattr_block(
> STATIC int
> xchk_xattr_rec(
> struct xchk_da_btree *ds,
> - int level,
> - void *rec)
> + int level)
> {
> struct xfs_mount *mp = ds->state->mp;
> - struct xfs_attr_leaf_entry *ent = rec;
> - struct xfs_da_state_blk *blk;
> + struct xfs_da_state_blk *blk = &ds->state->path.blk[level];
> struct xfs_attr_leaf_name_local *lentry;
> struct xfs_attr_leaf_name_remote *rentry;
> struct xfs_buf *bp;
> + struct xfs_attr_leaf_entry *ent;
> xfs_dahash_t calc_hash;
> xfs_dahash_t hash;
> int nameidx;
> @@ -414,7 +413,9 @@ xchk_xattr_rec(
> unsigned int badflags;
> int error;
>
> - blk = &ds->state->path.blk[level];
> + ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
> +
> + ent = xfs_attr3_leaf_entryp(blk->bp->b_addr) + blk->index;
>
> /* Check the whole block, if necessary. */
> error = xchk_xattr_block(ds, level);
> diff --git a/fs/xfs/scrub/dabtree.c b/fs/xfs/scrub/dabtree.c
> index 77ff9f97bcda..d1248c223c7f 100644
> --- a/fs/xfs/scrub/dabtree.c
> +++ b/fs/xfs/scrub/dabtree.c
> @@ -77,40 +77,17 @@ xchk_da_set_corrupt(
> __return_address);
> }
>
> -/* Find an entry at a certain level in a da btree. */
> -STATIC void *
> -xchk_da_btree_entry(
> - struct xchk_da_btree *ds,
> - int level,
> - int rec)
> +static struct xfs_da_node_entry *
> +xchk_da_btree_node_entry(
> + struct xchk_da_btree *ds,
> + int level)
> {
> - char *ents;
> - struct xfs_da_state_blk *blk;
> - void *baddr;
> + struct xfs_da_state_blk *blk = &ds->state->path.blk[level];
>
> - /* Dispatch the entry finding function. */
> - blk = &ds->state->path.blk[level];
> - baddr = blk->bp->b_addr;
> - switch (blk->magic) {
> - case XFS_ATTR_LEAF_MAGIC:
> - case XFS_ATTR3_LEAF_MAGIC:
> - ents = (char *)xfs_attr3_leaf_entryp(baddr);
> - return ents + (rec * sizeof(struct xfs_attr_leaf_entry));
> - case XFS_DIR2_LEAFN_MAGIC:
> - case XFS_DIR3_LEAFN_MAGIC:
> - ents = (char *)ds->dargs.dp->d_ops->leaf_ents_p(baddr);
> - return ents + (rec * sizeof(struct xfs_dir2_leaf_entry));
> - case XFS_DIR2_LEAF1_MAGIC:
> - case XFS_DIR3_LEAF1_MAGIC:
> - ents = (char *)ds->dargs.dp->d_ops->leaf_ents_p(baddr);
> - return ents + (rec * sizeof(struct xfs_dir2_leaf_entry));
> - case XFS_DA_NODE_MAGIC:
> - case XFS_DA3_NODE_MAGIC:
> - ents = (char *)ds->dargs.dp->d_ops->node_tree_p(baddr);
> - return ents + (rec * sizeof(struct xfs_da_node_entry));
> - }
> + ASSERT(blk->magic == XFS_DA_NODE_MAGIC);
>
> - return NULL;
> + return (void *)ds->dargs.dp->d_ops->node_tree_p(blk->bp->b_addr) +
> + (blk->index * sizeof(struct xfs_da_node_entry));
> }
>
> /* Scrub a da btree hash (key). */
> @@ -136,7 +113,7 @@ xchk_da_btree_hash(
>
> /* Is this hash no larger than the parent hash? */
> blks = ds->state->path.blk;
> - entry = xchk_da_btree_entry(ds, level - 1, blks[level - 1].index);

This eliminates the only user of blks, which means the variable can be
removed. The rest looks fine though.

--D

> + entry = xchk_da_btree_node_entry(ds, level - 1);
> parent_hash = be32_to_cpu(entry->hashval);
> if (parent_hash < hash)
> xchk_da_set_corrupt(ds, level);
> @@ -479,7 +456,6 @@ xchk_da_btree(
> struct xfs_mount *mp = sc->mp;
> struct xfs_da_state_blk *blks;
> struct xfs_da_node_entry *key;
> - void *rec;
> xfs_dablk_t blkno;
> int level;
> int error;
> @@ -538,9 +514,7 @@ xchk_da_btree(
> }
>
> /* Dispatch record scrubbing. */
> - rec = xchk_da_btree_entry(&ds, level,
> - blks[level].index);
> - error = scrub_fn(&ds, level, rec);
> + error = scrub_fn(&ds, level);
> if (error)
> break;
> if (xchk_should_terminate(sc, &error) ||
> @@ -562,7 +536,7 @@ xchk_da_btree(
> }
>
> /* Hashes in order for scrub? */
> - key = xchk_da_btree_entry(&ds, level, blks[level].index);
> + key = xchk_da_btree_node_entry(&ds, level);
> error = xchk_da_btree_hash(&ds, level, &key->hashval);
> if (error)
> goto out;
> diff --git a/fs/xfs/scrub/dabtree.h b/fs/xfs/scrub/dabtree.h
> index cb3f0003245b..1f3515c6d5a8 100644
> --- a/fs/xfs/scrub/dabtree.h
> +++ b/fs/xfs/scrub/dabtree.h
> @@ -28,8 +28,7 @@ struct xchk_da_btree {
> int tree_level;
> };
>
> -typedef int (*xchk_da_btree_rec_fn)(struct xchk_da_btree *ds,
> - int level, void *rec);
> +typedef int (*xchk_da_btree_rec_fn)(struct xchk_da_btree *ds, int level);
>
> /* Check for da btree operation errors. */
> bool xchk_da_process_error(struct xchk_da_btree *ds, int level, int *error);
> diff --git a/fs/xfs/scrub/dir.c b/fs/xfs/scrub/dir.c
> index 1e2e11721eb9..97f274f7cd38 100644
> --- a/fs/xfs/scrub/dir.c
> +++ b/fs/xfs/scrub/dir.c
> @@ -179,14 +179,14 @@ xchk_dir_actor(
> STATIC int
> xchk_dir_rec(
> struct xchk_da_btree *ds,
> - int level,
> - void *rec)
> + int level)
> {
> + struct xfs_da_state_blk *blk = &ds->state->path.blk[level];
> struct xfs_mount *mp = ds->state->mp;
> - struct xfs_dir2_leaf_entry *ent = rec;
> struct xfs_inode *dp = ds->dargs.dp;
> struct xfs_dir2_data_entry *dent;
> struct xfs_buf *bp;
> + struct xfs_dir2_leaf_entry *ent;
> char *p, *endp;
> xfs_ino_t ino;
> xfs_dablk_t rec_bno;
> @@ -198,6 +198,12 @@ xchk_dir_rec(
> unsigned int tag;
> int error;
>
> + ASSERT(blk->magic == XFS_DIR2_LEAF1_MAGIC ||
> + blk->magic == XFS_DIR2_LEAFN_MAGIC);
> +
> + ent = (void *)ds->dargs.dp->d_ops->leaf_ents_p(blk->bp->b_addr) +
> + (blk->index * sizeof(struct xfs_dir2_leaf_entry));
> +
> /* Check the hash of the entry. */
> error = xchk_da_btree_hash(ds, level, &ent->hashval);
> if (error)
> --
> 2.20.1
>