bcachefs: Convert more fsck code to for_each_btree_key2()

The new for_each_btree_key2() macro handles transaction retries,
allowing us to avoid nested transactions - which we want to avoid since
they're tricky to do completely correctly and upcoming assertions are
going to be checking for that.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

diff --git a/fs/bcachefs/fsck.c b/fs/bcachefs/fsck.c
index 6165878c2ddc4c90172b4aa7d7c7d0d370f97788..8f006b9a48047ed17aeb28a84ec700d91323dcb9 100644 (file)
--- a/fs/bcachefs/fsck.c
+++ b/fs/bcachefs/fsck.c
@@ -1003,10 +1003,8 @@ static int check_inodes(struct bch_fs *c, bool full)
 
        ret = for_each_btree_key_commit(&trans, iter, BTREE_ID_inodes,
                        POS_MIN,
-                       BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS,
-                       k,
-                       NULL, NULL,
-                       BTREE_INSERT_LAZY_RW|BTREE_INSERT_NOFAIL,
+                       BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS, k,
+                       NULL, NULL, BTREE_INSERT_LAZY_RW|BTREE_INSERT_NOFAIL,
                check_inode(&trans, &iter, k, &prev, &s, full));
 
        bch2_trans_exit(&trans);
@@ -2194,6 +2192,47 @@ static int check_nlinks_walk_dirents(struct bch_fs *c, struct nlink_table *links
        return ret;
 }
 
+static int check_nlinks_update_inode(struct btree_trans *trans, struct btree_iter *iter,
+                                    struct bkey_s_c k,
+                                    struct nlink_table *links,
+                                    size_t *idx, u64 range_end)
+{
+       struct bch_fs *c = trans->c;
+       struct bch_inode_unpacked u;
+       struct nlink *link = &links->d[*idx];
+       int ret = 0;
+
+       if (k.k->p.offset >= range_end)
+               return 1;
+
+       if (!bkey_is_inode(k.k))
+               return 0;
+
+       BUG_ON(bch2_inode_unpack(k, &u));
+
+       if (S_ISDIR(le16_to_cpu(u.bi_mode)))
+               return 0;
+
+       if (!u.bi_nlink)
+               return 0;
+
+       while ((cmp_int(link->inum, k.k->p.offset) ?:
+               cmp_int(link->snapshot, k.k->p.snapshot)) < 0) {
+               BUG_ON(*idx == links->nr);
+               link = &links->d[++*idx];
+       }
+
+       if (fsck_err_on(bch2_inode_nlink_get(&u) != link->count, c,
+                       "inode %llu type %s has wrong i_nlink (%u, should be %u)",
+                       u.bi_inum, bch2_d_types[mode_to_type(u.bi_mode)],
+                       bch2_inode_nlink_get(&u), link->count)) {
+               bch2_inode_nlink_set(&u, link->count);
+               ret = __write_inode(trans, &u, k.k->p.snapshot);
+       }
+fsck_err:
+       return ret;
+}
+
 noinline_for_stack
 static int check_nlinks_update_hardlinks(struct bch_fs *c,
                               struct nlink_table *links,
@@ -2202,56 +2241,25 @@ static int check_nlinks_update_hardlinks(struct bch_fs *c,
        struct btree_trans trans;
        struct btree_iter iter;
        struct bkey_s_c k;
-       struct bch_inode_unpacked u;
-       struct nlink *link = links->d;
+       size_t idx = 0;
        int ret = 0;
 
        bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
 
-       for_each_btree_key(&trans, iter, BTREE_ID_inodes,
-                          POS(0, range_start),
-                          BTREE_ITER_INTENT|
-                          BTREE_ITER_PREFETCH|
-                          BTREE_ITER_ALL_SNAPSHOTS, k, ret) {
-               if (k.k->p.offset >= range_end)
-                       break;
-
-               if (!bkey_is_inode(k.k))
-                       continue;
-
-               BUG_ON(bch2_inode_unpack(k, &u));
-
-               if (S_ISDIR(le16_to_cpu(u.bi_mode)))
-                       continue;
-
-               if (!u.bi_nlink)
-                       continue;
-
-               while ((cmp_int(link->inum, k.k->p.offset) ?:
-                       cmp_int(link->snapshot, k.k->p.snapshot)) < 0) {
-                       link++;
-                       BUG_ON(link >= links->d + links->nr);
-               }
-
-               if (fsck_err_on(bch2_inode_nlink_get(&u) != link->count, c,
-                               "inode %llu type %s has wrong i_nlink (%u, should be %u)",
-                               u.bi_inum, bch2_d_types[mode_to_type(u.bi_mode)],
-                               bch2_inode_nlink_get(&u), link->count)) {
-                       bch2_inode_nlink_set(&u, link->count);
+       ret = for_each_btree_key_commit(&trans, iter, BTREE_ID_inodes,
+                       POS(0, range_start),
+                       BTREE_ITER_INTENT|BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS, k,
+                       NULL, NULL, BTREE_INSERT_LAZY_RW|BTREE_INSERT_NOFAIL,
+               check_nlinks_update_inode(&trans, &iter, k, links, &idx, range_end));
 
-                       ret = write_inode(&trans, &u, k.k->p.snapshot);
-                       if (ret)
-                               bch_err(c, "error in fsck: error %i updating inode", ret);
-               }
-       }
-fsck_err:
-       bch2_trans_iter_exit(&trans, &iter);
        bch2_trans_exit(&trans);
 
-       if (ret)
+       if (ret < 0) {
                bch_err(c, "error in fsck: btree error %i while walking inodes", ret);
+               return ret;
+       }
 
-       return ret;
+       return 0;
 }
 
 noinline_for_stack
@@ -2291,21 +2299,13 @@ static int check_nlinks(struct bch_fs *c)
        return ret;
 }
 
-static int fix_reflink_p_key(struct btree_trans *trans, struct btree_iter *iter)
+static int fix_reflink_p_key(struct btree_trans *trans, struct btree_iter *iter,
+                            struct bkey_s_c k)
 {
-       struct bkey_s_c k;
        struct bkey_s_c_reflink_p p;
        struct bkey_i_reflink_p *u;
        int ret;
 
-       k = bch2_btree_iter_peek(iter);
-       if (!k.k)
-               return 0;
-
-       ret = bkey_err(k);
-       if (ret)
-               return ret;
-
        if (k.k->type != KEY_TYPE_reflink_p)
                return 0;
 
@@ -2341,20 +2341,11 @@ static int fix_reflink_p(struct bch_fs *c)
 
        bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
 
-       for_each_btree_key(&trans, iter, BTREE_ID_extents, POS_MIN,
-                          BTREE_ITER_INTENT|
-                          BTREE_ITER_PREFETCH|
-                          BTREE_ITER_ALL_SNAPSHOTS, k, ret) {
-               if (k.k->type == KEY_TYPE_reflink_p) {
-                       ret = commit_do(&trans, NULL, NULL,
-                                             BTREE_INSERT_NOFAIL|
-                                             BTREE_INSERT_LAZY_RW,
-                                             fix_reflink_p_key(&trans, &iter));
-                       if (ret)
-                               break;
-               }
-       }
-       bch2_trans_iter_exit(&trans, &iter);
+       ret = for_each_btree_key_commit(&trans, iter,
+                       BTREE_ID_extents, POS_MIN,
+                       BTREE_ITER_INTENT|BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS, k,
+                       NULL, NULL, BTREE_INSERT_NOFAIL|BTREE_INSERT_LAZY_RW,
+               fix_reflink_p_key(&trans, &iter, k));
 
        bch2_trans_exit(&trans);
        return ret;