bcachefs: Improve bch2_lock_inodes()

Can now be used for the two different types of locks we have so far
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/fs-ioctl.c

@@ -205,7 +205,7 @@ static int bch2_ioc_reinherit_attrs(struct bch_fs *c,
 	if (ret)
 		goto err2;
 
-	bch2_lock_inodes(src, dst);
+	bch2_lock_inodes(INODE_UPDATE_LOCK, src, dst);
 
 	if (inode_attr_changing(src, dst, Inode_opt_project)) {
 		ret = bch2_fs_quota_transfer(c, dst,
@@ -218,7 +218,7 @@ static int bch2_ioc_reinherit_attrs(struct bch_fs *c,
 
 	ret = bch2_write_inode(c, dst, bch2_reinherit_attrs_fn, src, 0);
 err3:
-	bch2_unlock_inodes(src, dst);
+	bch2_unlock_inodes(INODE_UPDATE_LOCK, src, dst);
 
 	/* return true if we did work */
 	if (ret >= 0)

fs/bcachefs/fs.c

@@ -657,7 +657,7 @@ static int bch2_unlink(struct inode *vdir, struct dentry *dentry)
 	struct btree_trans trans;
 	int ret;
 
-	bch2_lock_inodes(dir, inode);
+	bch2_lock_inodes(INODE_UPDATE_LOCK, dir, inode);
 	bch2_trans_init(&trans, c, 4, 1024);
 retry:
 	bch2_trans_begin(&trans);
@@ -690,7 +690,7 @@ static int bch2_unlink(struct inode *vdir, struct dentry *dentry)
 				      ATTR_MTIME);
 err:
 	bch2_trans_exit(&trans);
-	bch2_unlock_inodes(dir, inode);
+	bch2_unlock_inodes(INODE_UPDATE_LOCK, dir, inode);
 
 	return ret;
 }
@@ -871,7 +871,8 @@ static int bch2_rename2(struct mnt_idmap *idmap,
 
 	bch2_trans_init(&trans, c, 8, 2048);
 
-	bch2_lock_inodes(i.src_dir,
+	bch2_lock_inodes(INODE_UPDATE_LOCK,
+			 i.src_dir,
 			 i.dst_dir,
 			 i.src_inode,
 			 i.dst_inode);
@@ -969,7 +970,8 @@ static int bch2_rename2(struct mnt_idmap *idmap,
 				       1 << QTYP_PRJ,
 				       KEY_TYPE_QUOTA_NOCHECK);
 
-	bch2_unlock_inodes(i.src_dir,
+	bch2_unlock_inodes(INODE_UPDATE_LOCK,
+			   i.src_dir,
 			   i.dst_dir,
 			   i.src_inode,
 			   i.dst_inode);

fs/bcachefs/fs.h

@@ -57,24 +57,42 @@ static inline int ptrcmp(void *l, void *r)
 	return cmp_int(l, r);
 }
 
-#define __bch2_lock_inodes(_lock, ...)					\
+enum bch_inode_lock_op {
+	INODE_LOCK		= (1U << 0),
+	INODE_UPDATE_LOCK	= (1U << 1),
+};
+
+#define bch2_lock_inodes(_locks, ...)					\
 do {									\
 	struct bch_inode_info *a[] = { NULL, __VA_ARGS__ };		\
 	unsigned i;							\
 									\
-	bubble_sort(&a[1], ARRAY_SIZE(a) - 1 , ptrcmp);			\
+	bubble_sort(&a[1], ARRAY_SIZE(a) - 1, ptrcmp);			\
 									\
-	for (i = ARRAY_SIZE(a) - 1; a[i]; --i)				\
+	for (i = 1; i < ARRAY_SIZE(a); i++)				\
 		if (a[i] != a[i - 1]) {					\
-			if (_lock)					\
+			if (_locks & INODE_LOCK)			\
+				down_write_nested(&a[i]->v.i_rwsem, i);	\
+			if (_locks & INODE_UPDATE_LOCK)			\
 				mutex_lock_nested(&a[i]->ei_update_lock, i);\
-			else						\
-				mutex_unlock(&a[i]->ei_update_lock);	\
 		}							\
 } while (0)
 
-#define bch2_lock_inodes(...)	__bch2_lock_inodes(true, __VA_ARGS__)
-#define bch2_unlock_inodes(...)	__bch2_lock_inodes(false, __VA_ARGS__)
+#define bch2_unlock_inodes(_locks, ...)					\
+do {									\
+	struct bch_inode_info *a[] = { NULL, __VA_ARGS__ };		\
+	unsigned i;							\
+									\
+	bubble_sort(&a[1], ARRAY_SIZE(a) - 1, ptrcmp);			\
+									\
+	for (i = 1; i < ARRAY_SIZE(a); i++)				\
+		if (a[i] != a[i - 1]) {					\
+			if (_locks & INODE_LOCK)			\
+				up_write(&a[i]->v.i_rwsem);		\
+			if (_locks & INODE_UPDATE_LOCK)			\
+				mutex_unlock(&a[i]->ei_update_lock);	\
+		}							\
+} while (0)
 
 static inline struct bch_inode_info *file_bch_inode(struct file *file)
 {