bcachefs: Factor out fs-common.c

This refactoring makes the code easier to understand by separating the
bcachefs btree transactional code from the linux VFS code - but more
importantly, it's also to share code with the fuse port.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 280 insertions, 0 deletions

diff --git a/fs/bcachefs/fs-common.c b/fs/bcachefs/fs-common.c
new file mode 100644
index 000000000000..fdd2b9b6716f
--- /dev/null
+++ b/fs/bcachefs/fs-common.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "bcachefs.h"
+#include "acl.h"
+#include "btree_update.h"
+#include "dirent.h"
+#include "fs-common.h"
+#include "inode.h"
+#include "xattr.h"
+
+#include <linux/posix_acl.h>
+
+int bch2_create_trans(struct btree_trans *trans, u64 dir_inum,
+		      struct bch_inode_unpacked *dir_u,
+		      struct bch_inode_unpacked *new_inode,
+		      const struct qstr *name,
+		      uid_t uid, gid_t gid, umode_t mode, dev_t rdev,
+		      struct posix_acl *default_acl,
+		      struct posix_acl *acl)
+{
+	struct bch_fs *c = trans->c;
+	struct btree_iter *dir_iter;
+	struct bch_hash_info hash = bch2_hash_info_init(c, new_inode);
+	u64 now = bch2_current_time(trans->c);
+	int ret;
+
+	dir_iter = bch2_inode_peek(trans, dir_u, dir_inum,
+				   name ? BTREE_ITER_INTENT : 0);
+	if (IS_ERR(dir_iter))
+		return PTR_ERR(dir_iter);
+
+	bch2_inode_init_late(new_inode, now, uid, gid, mode, rdev, dir_u);
+
+	if (!name)
+		new_inode->bi_flags |= BCH_INODE_UNLINKED;
+
+	ret = bch2_inode_create(trans, new_inode,
+				BLOCKDEV_INODE_MAX, 0,
+				&c->unused_inode_hint);
+	if (ret)
+		return ret;
+
+	if (default_acl) {
+		ret = bch2_set_acl_trans(trans, new_inode, &hash,
+					 default_acl, ACL_TYPE_DEFAULT);
+		if (ret)
+			return ret;
+	}
+
+	if (acl) {
+		ret = bch2_set_acl_trans(trans, new_inode, &hash,
+					 acl, ACL_TYPE_ACCESS);
+		if (ret)
+			return ret;
+	}
+
+	if (name) {
+		struct bch_hash_info dir_hash = bch2_hash_info_init(c, dir_u);
+		dir_u->bi_mtime = dir_u->bi_ctime = now;
+
+		if (S_ISDIR(new_inode->bi_mode))
+			dir_u->bi_nlink++;
+
+		ret = bch2_inode_write(trans, dir_iter, dir_u);
+		if (ret)
+			return ret;
+
+		ret = bch2_dirent_create(trans, dir_inum, &dir_hash,
+					 mode_to_type(new_inode->bi_mode),
+					 name, new_inode->bi_inum,
+					 BCH_HASH_SET_MUST_CREATE);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+int bch2_link_trans(struct btree_trans *trans,
+		    u64 dir_inum,
+		    u64 inum, struct bch_inode_unpacked *inode_u,
+		    const struct qstr *name)
+{
+	struct btree_iter *dir_iter, *inode_iter;
+	struct bch_inode_unpacked dir_u;
+	struct bch_hash_info dir_hash;
+	u64 now = bch2_current_time(trans->c);
+
+	dir_iter = bch2_inode_peek(trans, &dir_u, dir_inum, 0);
+	if (IS_ERR(dir_iter))
+		return PTR_ERR(dir_iter);
+
+	inode_iter = bch2_inode_peek(trans, inode_u, inum, BTREE_ITER_INTENT);
+	if (IS_ERR(inode_iter))
+		return PTR_ERR(inode_iter);
+
+	dir_hash = bch2_hash_info_init(trans->c, &dir_u);
+
+	inode_u->bi_ctime = now;
+	bch2_inode_nlink_inc(inode_u);
+
+	return bch2_dirent_create(trans, dir_inum, &dir_hash,
+				  mode_to_type(inode_u->bi_mode),
+				  name, inum, BCH_HASH_SET_MUST_CREATE) ?:
+		bch2_inode_write(trans, inode_iter, inode_u);
+}
+
+int bch2_unlink_trans(struct btree_trans *trans,
+		      u64 dir_inum, struct bch_inode_unpacked *dir_u,
+		      struct bch_inode_unpacked *inode_u,
+		      const struct qstr *name)
+{
+	struct btree_iter *dir_iter, *dirent_iter, *inode_iter;
+	struct bch_hash_info dir_hash;
+	u64 inum, now = bch2_current_time(trans->c);
+	struct bkey_s_c k;
+
+	dir_iter = bch2_inode_peek(trans, dir_u, dir_inum, BTREE_ITER_INTENT);
+	if (IS_ERR(dir_iter))
+		return PTR_ERR(dir_iter);
+
+	dir_hash = bch2_hash_info_init(trans->c, dir_u);
+
+	dirent_iter = __bch2_dirent_lookup_trans(trans, dir_inum,
+						 &dir_hash, name);
+	if (IS_ERR(dirent_iter))
+		return PTR_ERR(dirent_iter);
+
+	k = bch2_btree_iter_peek_slot(dirent_iter);
+	inum = le64_to_cpu(bkey_s_c_to_dirent(k).v->d_inum);
+
+	inode_iter = bch2_inode_peek(trans, inode_u, inum, BTREE_ITER_INTENT);
+	if (IS_ERR(inode_iter))
+		return PTR_ERR(inode_iter);
+
+	dir_u->bi_mtime = dir_u->bi_ctime = inode_u->bi_ctime = now;
+	dir_u->bi_nlink -= S_ISDIR(inode_u->bi_mode);
+	bch2_inode_nlink_dec(inode_u);
+
+	return  (S_ISDIR(inode_u->bi_mode)
+		 ? bch2_empty_dir_trans(trans, inum)
+		 : 0) ?:
+		bch2_dirent_delete_at(trans, &dir_hash, dirent_iter) ?:
+		bch2_inode_write(trans, dir_iter, dir_u) ?:
+		bch2_inode_write(trans, inode_iter, inode_u);
+}
+
+bool bch2_reinherit_attrs(struct bch_inode_unpacked *dst_u,
+			  struct bch_inode_unpacked *src_u)
+{
+	u64 src, dst;
+	unsigned id;
+	bool ret = false;
+
+	for (id = 0; id < Inode_opt_nr; id++) {
+		if (dst_u->bi_fields_set & (1 << id))
+			continue;
+
+		src = bch2_inode_opt_get(src_u, id);
+		dst = bch2_inode_opt_get(dst_u, id);
+
+		if (src == dst)
+			continue;
+
+		bch2_inode_opt_set(dst_u, id, src);
+		ret = true;
+	}
+
+	return ret;
+}
+
+int bch2_rename_trans(struct btree_trans *trans,
+		      u64 src_dir, struct bch_inode_unpacked *src_dir_u,
+		      u64 dst_dir, struct bch_inode_unpacked *dst_dir_u,
+		      struct bch_inode_unpacked *src_inode_u,
+		      struct bch_inode_unpacked *dst_inode_u,
+		      const struct qstr *src_name,
+		      const struct qstr *dst_name,
+		      enum bch_rename_mode mode)
+{
+	struct btree_iter *src_dir_iter, *dst_dir_iter = NULL;
+	struct btree_iter *src_inode_iter, *dst_inode_iter = NULL;
+	struct bch_hash_info src_hash, dst_hash;
+	u64 src_inode, dst_inode, now = bch2_current_time(trans->c);
+	int ret;
+
+	src_dir_iter = bch2_inode_peek(trans, src_dir_u, src_dir,
+				       BTREE_ITER_INTENT);
+	if (IS_ERR(src_dir_iter))
+		return PTR_ERR(src_dir_iter);
+
+	src_hash = bch2_hash_info_init(trans->c, src_dir_u);
+
+	if (dst_dir != src_dir) {
+		dst_dir_iter = bch2_inode_peek(trans, dst_dir_u, dst_dir,
+					       BTREE_ITER_INTENT);
+		if (IS_ERR(dst_dir_iter))
+			return PTR_ERR(dst_dir_iter);
+
+		dst_hash = bch2_hash_info_init(trans->c, dst_dir_u);
+	} else {
+		dst_dir_u = src_dir_u;
+		dst_hash = src_hash;
+	}
+
+	ret = bch2_dirent_rename(trans,
+				 src_dir, &src_hash,
+				 dst_dir, &dst_hash,
+				 src_name, &src_inode,
+				 dst_name, &dst_inode,
+				 mode);
+	if (ret)
+		return ret;
+
+	src_inode_iter = bch2_inode_peek(trans, src_inode_u, src_inode,
+					 BTREE_ITER_INTENT);
+	if (IS_ERR(src_inode_iter))
+		return PTR_ERR(src_inode_iter);
+
+	if (dst_inode) {
+		dst_inode_iter = bch2_inode_peek(trans, dst_inode_u, dst_inode,
+						 BTREE_ITER_INTENT);
+		if (IS_ERR(dst_inode_iter))
+			return PTR_ERR(dst_inode_iter);
+	}
+
+	if (mode == BCH_RENAME_OVERWRITE) {
+		if (S_ISDIR(src_inode_u->bi_mode) !=
+		    S_ISDIR(dst_inode_u->bi_mode))
+			return -ENOTDIR;
+
+		if (S_ISDIR(dst_inode_u->bi_mode) &&
+		    bch2_empty_dir_trans(trans, dst_inode))
+			return -ENOTEMPTY;
+	}
+
+	if (bch2_reinherit_attrs(src_inode_u, dst_dir_u) &&
+	    S_ISDIR(src_inode_u->bi_mode))
+		return -EXDEV;
+
+	if (mode == BCH_RENAME_EXCHANGE &&
+	    bch2_reinherit_attrs(dst_inode_u, src_dir_u) &&
+	    S_ISDIR(dst_inode_u->bi_mode))
+		return -EXDEV;
+
+	if (S_ISDIR(src_inode_u->bi_mode)) {
+		src_dir_u->bi_nlink--;
+		dst_dir_u->bi_nlink++;
+	}
+
+	if (dst_inode && S_ISDIR(dst_inode_u->bi_mode)) {
+		dst_dir_u->bi_nlink--;
+		src_dir_u->bi_nlink += mode == BCH_RENAME_EXCHANGE;
+	}
+
+	if (mode == BCH_RENAME_OVERWRITE)
+		bch2_inode_nlink_dec(dst_inode_u);
+
+	src_dir_u->bi_mtime		= now;
+	src_dir_u->bi_ctime		= now;
+
+	if (src_dir != dst_dir) {
+		dst_dir_u->bi_mtime	= now;
+		dst_dir_u->bi_ctime	= now;
+	}
+
+	src_inode_u->bi_ctime		= now;
+
+	if (dst_inode)
+		dst_inode_u->bi_ctime	= now;
+
+	return  bch2_inode_write(trans, src_dir_iter, src_dir_u) ?:
+		(src_dir != dst_dir
+		 ? bch2_inode_write(trans, dst_dir_iter, dst_dir_u)
+		 : 0 ) ?:
+		bch2_inode_write(trans, src_inode_iter, src_inode_u) ?:
+		(dst_inode
+		 ? bch2_inode_write(trans, dst_inode_iter, dst_inode_u)
+		 : 0 );
+}