Merge tag 'bcachefs-2025-05-22' of git://evilpiepirate.org/bcachefs

Pull bcachefs fixes from Kent Overstreet:
 "Small stuff, main ones users will be interested in:

   - Couple more casefolding fixes; we can now detect and repair
     casefolded dirents in non-casefolded dir and vice versa

   - Fix for massive write inflation with mmapped io, which hit certain
     databases"

* tag 'bcachefs-2025-05-22' of git://evilpiepirate.org/bcachefs:
  bcachefs: Check for casefolded dirents in non casefolded dirs
  bcachefs: Fix bch2_dirent_create_snapshot() for casefolding
  bcachefs: Fix casefold opt via xattr interface
  bcachefs: mkwrite() now only dirties one page
  bcachefs: fix extent_has_stripe_ptr()
  bcachefs: Fix bch2_btree_path_traverse_cached() when paths realloced

Author: torvalds

fs/bcachefs/btree_iter.c

@@ -1162,7 +1162,7 @@ int bch2_btree_path_traverse_one(struct btree_trans *trans,
 	}
 
 	if (path->cached) {
-		ret = bch2_btree_path_traverse_cached(trans, path, flags);
+		ret = bch2_btree_path_traverse_cached(trans, path_idx, flags);
 		goto out;
 	}
 

fs/bcachefs/btree_key_cache.c

@@ -301,9 +301,11 @@ static noinline_for_stack void do_trace_key_cache_fill(struct btree_trans *trans
 }
 
 static noinline int btree_key_cache_fill(struct btree_trans *trans,
-					 struct btree_path *ck_path,
+					 btree_path_idx_t ck_path_idx,
 					 unsigned flags)
 {
+	struct btree_path *ck_path = trans->paths + ck_path_idx;
+
 	if (flags & BTREE_ITER_cached_nofill) {
 		ck_path->l[0].b = NULL;
 		return 0;
@@ -325,6 +327,7 @@ static noinline int btree_key_cache_fill(struct btree_trans *trans,
 		goto err;
 
 	/* Recheck after btree lookup, before allocating: */
+	ck_path = trans->paths + ck_path_idx;
 	ret = bch2_btree_key_cache_find(c, ck_path->btree_id, ck_path->pos) ? -EEXIST : 0;
 	if (unlikely(ret))
 		goto out;
@@ -344,10 +347,11 @@ static noinline int btree_key_cache_fill(struct btree_trans *trans,
 }
 
 static inline int btree_path_traverse_cached_fast(struct btree_trans *trans,
-						  struct btree_path *path)
+						  btree_path_idx_t path_idx)
 {
 	struct bch_fs *c = trans->c;
 	struct bkey_cached *ck;
+	struct btree_path *path = trans->paths + path_idx;
 retry:
 	ck = bch2_btree_key_cache_find(c, path->btree_id, path->pos);
 	if (!ck)
@@ -373,27 +377,32 @@ static inline int btree_path_traverse_cached_fast(struct btree_trans *trans,
 	return 0;
 }
 
-int bch2_btree_path_traverse_cached(struct btree_trans *trans, struct btree_path *path,
+int bch2_btree_path_traverse_cached(struct btree_trans *trans,
+				    btree_path_idx_t path_idx,
 				    unsigned flags)
 {
-	EBUG_ON(path->level);
-
-	path->l[1].b = NULL;
+	EBUG_ON(trans->paths[path_idx].level);
 
 	int ret;
 	do {
-		ret = btree_path_traverse_cached_fast(trans, path);
+		ret = btree_path_traverse_cached_fast(trans, path_idx);
 		if (unlikely(ret == -ENOENT))
-			ret = btree_key_cache_fill(trans, path, flags);
+			ret = btree_key_cache_fill(trans, path_idx, flags);
 	} while (ret == -EEXIST);
 
+	struct btree_path *path = trans->paths + path_idx;
+
 	if (unlikely(ret)) {
 		path->uptodate = BTREE_ITER_NEED_TRAVERSE;
 		if (!bch2_err_matches(ret, BCH_ERR_transaction_restart)) {
 			btree_node_unlock(trans, path, 0);
 			path->l[0].b = ERR_PTR(ret);
 		}
+	} else {
+		BUG_ON(path->uptodate);
+		BUG_ON(!path->nodes_locked);
 	}
+
 	return ret;
 }
 

fs/bcachefs/btree_key_cache.h

@@ -40,8 +40,7 @@ int bch2_btree_key_cache_journal_flush(struct journal *,
 struct bkey_cached *
 bch2_btree_key_cache_find(struct bch_fs *, enum btree_id, struct bpos);
 
-int bch2_btree_path_traverse_cached(struct btree_trans *, struct btree_path *,
-				    unsigned);
+int bch2_btree_path_traverse_cached(struct btree_trans *, btree_path_idx_t, unsigned);
 
 bool bch2_btree_insert_key_cached(struct btree_trans *, unsigned,
 			struct btree_insert_entry *);

fs/bcachefs/dirent.c

@@ -288,17 +288,27 @@ static void dirent_init_casefolded_name(struct bkey_i_dirent *dirent,
 }
 
 static struct bkey_i_dirent *dirent_create_key(struct btree_trans *trans,
+				const struct bch_hash_info *hash_info,
 				subvol_inum dir,
 				u8 type,
 				const struct qstr *name,
 				const struct qstr *cf_name,
 				u64 dst)
 {
 	struct bkey_i_dirent *dirent;
+	struct qstr _cf_name;
 
 	if (name->len > BCH_NAME_MAX)
 		return ERR_PTR(-ENAMETOOLONG);
 
+	if (hash_info->cf_encoding && !cf_name) {
+		int ret = bch2_casefold(trans, hash_info, name, &_cf_name);
+		if (ret)
+			return ERR_PTR(ret);
+
+		cf_name = &_cf_name;
+	}
+
 	dirent = dirent_alloc_key(trans, dir, type, name->len, cf_name ? cf_name->len : 0, dst);
 	if (IS_ERR(dirent))
 		return dirent;
@@ -324,7 +334,7 @@ int bch2_dirent_create_snapshot(struct btree_trans *trans,
 	struct bkey_i_dirent *dirent;
 	int ret;
 
-	dirent = dirent_create_key(trans, dir_inum, type, name, NULL, dst_inum);
+	dirent = dirent_create_key(trans, hash_info, dir_inum, type, name, NULL, dst_inum);
 	ret = PTR_ERR_OR_ZERO(dirent);
 	if (ret)
 		return ret;
@@ -333,8 +343,7 @@ int bch2_dirent_create_snapshot(struct btree_trans *trans,
 	dirent->k.p.snapshot	= snapshot;
 
 	ret = bch2_hash_set_in_snapshot(trans, bch2_dirent_hash_desc, hash_info,
-					dir_inum, snapshot, &dirent->k_i,
-					flags|BTREE_UPDATE_internal_snapshot_node);
+					dir_inum, snapshot, &dirent->k_i, flags);
 	*dir_offset = dirent->k.p.offset;
 
 	return ret;
@@ -344,28 +353,16 @@ int bch2_dirent_create(struct btree_trans *trans, subvol_inum dir,
 		       const struct bch_hash_info *hash_info,
 		       u8 type, const struct qstr *name, u64 dst_inum,
 		       u64 *dir_offset,
-		       u64 *i_size,
 		       enum btree_iter_update_trigger_flags flags)
 {
 	struct bkey_i_dirent *dirent;
 	int ret;
 
-	if (hash_info->cf_encoding) {
-		struct qstr cf_name;
-		ret = bch2_casefold(trans, hash_info, name, &cf_name);
-		if (ret)
-			return ret;
-		dirent = dirent_create_key(trans, dir, type, name, &cf_name, dst_inum);
-	} else {
-		dirent = dirent_create_key(trans, dir, type, name, NULL, dst_inum);
-	}
-
+	dirent = dirent_create_key(trans, hash_info, dir, type, name, NULL, dst_inum);
 	ret = PTR_ERR_OR_ZERO(dirent);
 	if (ret)
 		return ret;
 
-	*i_size += bkey_bytes(&dirent->k);
-
 	ret = bch2_hash_set(trans, bch2_dirent_hash_desc, hash_info,
 			    dir, &dirent->k_i, flags);
 	*dir_offset = dirent->k.p.offset;
@@ -466,7 +463,7 @@ int bch2_dirent_rename(struct btree_trans *trans,
 		*src_offset = dst_iter.pos.offset;
 
 	/* Create new dst key: */
-	new_dst = dirent_create_key(trans, dst_dir, 0, dst_name,
+	new_dst = dirent_create_key(trans, dst_hash, dst_dir, 0, dst_name,
 				    dst_hash->cf_encoding ? &dst_name_lookup : NULL, 0);
 	ret = PTR_ERR_OR_ZERO(new_dst);
 	if (ret)
@@ -477,7 +474,7 @@ int bch2_dirent_rename(struct btree_trans *trans,
 
 	/* Create new src key: */
 	if (mode == BCH_RENAME_EXCHANGE) {
-		new_src = dirent_create_key(trans, src_dir, 0, src_name,
+		new_src = dirent_create_key(trans, src_hash, src_dir, 0, src_name,
 					    src_hash->cf_encoding ? &src_name_lookup : NULL, 0);
 		ret = PTR_ERR_OR_ZERO(new_src);
 		if (ret)

fs/bcachefs/dirent.h

@@ -65,7 +65,7 @@ int bch2_dirent_create_snapshot(struct btree_trans *, u32, u64, u32,
 			enum btree_iter_update_trigger_flags);
 int bch2_dirent_create(struct btree_trans *, subvol_inum,
 		       const struct bch_hash_info *, u8,
-		       const struct qstr *, u64, u64 *, u64 *,
+		       const struct qstr *, u64, u64 *,
 		       enum btree_iter_update_trigger_flags);
 
 static inline unsigned vfs_d_type(unsigned type)

fs/bcachefs/ec.c

@@ -507,20 +507,14 @@ static const struct bch_extent_ptr *bkey_matches_stripe(struct bch_stripe *s,
 
 static bool extent_has_stripe_ptr(struct bkey_s_c k, u64 idx)
 {
-	switch (k.k->type) {
-	case KEY_TYPE_extent: {
-		struct bkey_s_c_extent e = bkey_s_c_to_extent(k);
-		const union bch_extent_entry *entry;
-
-		extent_for_each_entry(e, entry)
-			if (extent_entry_type(entry) ==
-			    BCH_EXTENT_ENTRY_stripe_ptr &&
-			    entry->stripe_ptr.idx == idx)
-				return true;
+	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+	const union bch_extent_entry *entry;
 
-		break;
-	}
-	}
+	bkey_extent_entry_for_each(ptrs, entry)
+		if (extent_entry_type(entry) ==
+		    BCH_EXTENT_ENTRY_stripe_ptr &&
+		    entry->stripe_ptr.idx == idx)
+			return true;
 
 	return false;
 }

fs/bcachefs/extents.h

@@ -380,13 +380,6 @@ out:									\
 
 /* Iterate over pointers in KEY_TYPE_extent: */
 
-#define extent_for_each_entry_from(_e, _entry, _start)			\
-	__bkey_extent_entry_for_each_from(_start,			\
-				extent_entry_last(_e), _entry)
-
-#define extent_for_each_entry(_e, _entry)				\
-	extent_for_each_entry_from(_e, _entry, (_e).v->start)
-
 #define extent_ptr_next(_e, _ptr)					\
 	__bkey_ptr_next(_ptr, extent_entry_last(_e))
 

fs/bcachefs/fs-io-pagecache.c

@@ -605,10 +605,14 @@ vm_fault_t bch2_page_mkwrite(struct vm_fault *vmf)
 	struct address_space *mapping = file->f_mapping;
 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
 	struct bch2_folio_reservation res;
-	unsigned len;
-	loff_t isize;
 	vm_fault_t ret;
 
+	loff_t file_offset = round_down(vmf->pgoff << PAGE_SHIFT, block_bytes(c));
+	unsigned offset = file_offset - folio_pos(folio);
+	unsigned len = max(PAGE_SIZE, block_bytes(c));
+
+	BUG_ON(offset + len > folio_size(folio));
+
 	bch2_folio_reservation_init(c, inode, &res);
 
 	sb_start_pagefault(inode->v.i_sb);
@@ -623,24 +627,24 @@ vm_fault_t bch2_page_mkwrite(struct vm_fault *vmf)
 	bch2_pagecache_add_get(inode);
 
 	folio_lock(folio);
-	isize = i_size_read(&inode->v);
+	u64 isize = i_size_read(&inode->v);
 
-	if (folio->mapping != mapping || folio_pos(folio) >= isize) {
+	if (folio->mapping != mapping || file_offset >= isize) {
 		folio_unlock(folio);
 		ret = VM_FAULT_NOPAGE;
 		goto out;
 	}
 
-	len = min_t(loff_t, folio_size(folio), isize - folio_pos(folio));
+	len = min_t(unsigned, len, isize - file_offset);
 
 	if (bch2_folio_set(c, inode_inum(inode), &folio, 1) ?:
-	    bch2_folio_reservation_get(c, inode, folio, &res, 0, len)) {
+	    bch2_folio_reservation_get(c, inode, folio, &res, offset, len)) {
 		folio_unlock(folio);
 		ret = VM_FAULT_SIGBUS;
 		goto out;
 	}
 
-	bch2_set_folio_dirty(c, inode, folio, &res, 0, len);
+	bch2_set_folio_dirty(c, inode, folio, &res, offset, len);
 	bch2_folio_reservation_put(c, inode, &res);
 
 	folio_wait_stable(folio);

fs/bcachefs/fs.c

@@ -1664,33 +1664,9 @@ static int fssetxattr_inode_update_fn(struct btree_trans *trans,
 		return -EINVAL;
 
 	if (s->casefold != bch2_inode_casefold(c, bi)) {
-#ifdef CONFIG_UNICODE
-		int ret = 0;
-		/* Not supported on individual files. */
-		if (!S_ISDIR(bi->bi_mode))
-			return -EOPNOTSUPP;
-
-		/*
-		 * Make sure the dir is empty, as otherwise we'd need to
-		 * rehash everything and update the dirent keys.
-		 */
-		ret = bch2_empty_dir_trans(trans, inode_inum(inode));
-		if (ret < 0)
-			return ret;
-
-		ret = bch2_request_incompat_feature(c, bcachefs_metadata_version_casefolding);
+		int ret = bch2_inode_set_casefold(trans, inode_inum(inode), bi, s->casefold);
 		if (ret)
 			return ret;
-
-		bch2_check_set_feature(c, BCH_FEATURE_casefolding);
-
-		bi->bi_casefold = s->casefold + 1;
-		bi->bi_fields_set |= BIT(Inode_opt_casefold);
-
-#else
-		printk(KERN_ERR "Cannot use casefolding on a kernel without CONFIG_UNICODE\n");
-		return -EOPNOTSUPP;
-#endif
 	}
 
 	if (s->set_project) {

fs/bcachefs/fsck.c

@@ -306,6 +306,7 @@ static int lookup_lostfound(struct btree_trans *trans, u32 snapshot,
 				&lostfound_str,
 				lostfound->bi_inum,
 				&lostfound->bi_dir_offset,
+				BTREE_UPDATE_internal_snapshot_node|
 				STR_HASH_must_create) ?:
 		bch2_inode_write_flags(trans, &lostfound_iter, lostfound,
 				       BTREE_UPDATE_internal_snapshot_node);
@@ -431,6 +432,7 @@ static int reattach_inode(struct btree_trans *trans, struct bch_inode_unpacked *
 				&name,
 				inode->bi_subvol ?: inode->bi_inum,
 				&inode->bi_dir_offset,
+				BTREE_UPDATE_internal_snapshot_node|
 				STR_HASH_must_create);
 	if (ret) {
 		bch_err_msg(c, ret, "error creating dirent");
@@ -2188,6 +2190,41 @@ static int check_dirent(struct btree_trans *trans, struct btree_iter *iter,
 
 	struct bkey_s_c_dirent d = bkey_s_c_to_dirent(k);
 
+	/* check casefold */
+	if (fsck_err_on(d.v->d_casefold != !!hash_info->cf_encoding,
+			trans, dirent_casefold_mismatch,
+			"dirent casefold does not match dir casefold\n%s",
+			(printbuf_reset(&buf),
+			 bch2_bkey_val_to_text(&buf, c, k),
+			 buf.buf))) {
+		struct qstr name = bch2_dirent_get_name(d);
+		u32 subvol = d.v->d_type == DT_SUBVOL
+			? d.v->d_parent_subvol
+			: 0;
+		u64 target = d.v->d_type == DT_SUBVOL
+			? d.v->d_child_subvol
+			: d.v->d_inum;
+		u64 dir_offset;
+
+		ret =   bch2_hash_delete_at(trans,
+					    bch2_dirent_hash_desc, hash_info, iter,
+					    BTREE_UPDATE_internal_snapshot_node) ?:
+			bch2_dirent_create_snapshot(trans, subvol,
+						    d.k->p.inode, d.k->p.snapshot,
+						    hash_info,
+						    d.v->d_type,
+						    &name,
+						    target,
+						    &dir_offset,
+						    BTREE_ITER_with_updates|
+						    BTREE_UPDATE_internal_snapshot_node|
+						    STR_HASH_must_create) ?:
+			bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
+
+		/* might need another check_dirents pass */
+		goto out;
+	}
+
 	if (d.v->d_type == DT_SUBVOL) {
 		ret = check_dirent_to_subvol(trans, iter, d);
 		if (ret)