btrfs: add a BTRFS_FS_ERROR helper

We have a few flags that are inconsistently used to describe the fs in
different states of failure.  As of 5963ffca ("btrfs: always abort
the transaction if we abort a trans handle") we will always set
BTRFS_FS_STATE_ERROR if we abort, so we don't have to check both ABORTED
and ERROR to see if things have gone wrong.  Add a helper to check
BTRFS_FS_STATE_ERROR and then convert all checkers of FS_STATE_ERROR to
use the helper.

The TRANS_ABORTED bit check was added in af722733 ("Btrfs: clean up
resources during umount after trans is aborted") but is not actually
specific.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/ctree.h

@@ -3607,6 +3607,9 @@ do {								\
 			  (errno), fmt, ##args);		\
 } while (0)
 
+#define BTRFS_FS_ERROR(fs_info)	(unlikely(test_bit(BTRFS_FS_STATE_ERROR, \
+						   &(fs_info)->fs_state)))
+
 __printf(5, 6)
 __cold
 void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function,

fs/btrfs/disk-io.c

@@ -1954,8 +1954,7 @@ static int transaction_kthread(void *arg)
 		wake_up_process(fs_info->cleaner_kthread);
 		mutex_unlock(&fs_info->transaction_kthread_mutex);
 
-		if (unlikely(test_bit(BTRFS_FS_STATE_ERROR,
-				      &fs_info->fs_state)))
+		if (BTRFS_FS_ERROR(fs_info))
 			btrfs_cleanup_transaction(fs_info);
 		if (!kthread_should_stop() &&
 				(!btrfs_transaction_blocked(fs_info) ||
@@ -4232,7 +4231,7 @@ void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
 		drop_ref = true;
 	spin_unlock(&fs_info->fs_roots_radix_lock);
 
-	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
+	if (BTRFS_FS_ERROR(fs_info)) {
 		ASSERT(root->log_root == NULL);
 		if (root->reloc_root) {
 			btrfs_put_root(root->reloc_root);
@@ -4383,8 +4382,7 @@ void __cold close_ctree(struct btrfs_fs_info *fs_info)
 			btrfs_err(fs_info, "commit super ret %d", ret);
 	}
 
-	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state) ||
-	    test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state))
+	if (BTRFS_FS_ERROR(fs_info))
 		btrfs_error_commit_super(fs_info);
 
 	kthread_stop(fs_info->transaction_kthread);

fs/btrfs/extent_io.c

@@ -4908,7 +4908,7 @@ int btree_write_cache_pages(struct address_space *mapping,
 	 *   extent io tree. Thus we don't want to submit such wild eb
 	 *   if the fs already has error.
 	 */
-	if (!test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
+	if (!BTRFS_FS_ERROR(fs_info)) {
 		ret = flush_write_bio(&epd);
 	} else {
 		ret = -EROFS;

fs/btrfs/file.c

@@ -2018,7 +2018,7 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
 	 * have opened a file as writable, we have to stop this write operation
 	 * to ensure consistency.
 	 */
-	if (test_bit(BTRFS_FS_STATE_ERROR, &inode->root->fs_info->fs_state))
+	if (BTRFS_FS_ERROR(inode->root->fs_info))
 		return -EROFS;
 
 	if (!(iocb->ki_flags & IOCB_DIRECT) &&

fs/btrfs/inode.c

@@ -4380,7 +4380,7 @@ static void btrfs_prune_dentries(struct btrfs_root *root)
 	struct inode *inode;
 	u64 objectid = 0;
 
-	if (!test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
+	if (!BTRFS_FS_ERROR(fs_info))
 		WARN_ON(btrfs_root_refs(&root->root_item) != 0);
 
 	spin_lock(&root->inode_lock);
@@ -9998,7 +9998,7 @@ int btrfs_start_delalloc_snapshot(struct btrfs_root *root, bool in_reclaim_conte
 	};
 	struct btrfs_fs_info *fs_info = root->fs_info;
 
-	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
+	if (BTRFS_FS_ERROR(fs_info))
 		return -EROFS;
 
 	return start_delalloc_inodes(root, &wbc, true, in_reclaim_context);
@@ -10017,7 +10017,7 @@ int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr,
 	struct list_head splice;
 	int ret;
 
-	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
+	if (BTRFS_FS_ERROR(fs_info))
 		return -EROFS;
 
 	INIT_LIST_HEAD(&splice);

fs/btrfs/scrub.c

@@ -3955,7 +3955,7 @@ static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
 	int	ret;
 	struct btrfs_fs_info *fs_info = sctx->fs_info;
 
-	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
+	if (BTRFS_FS_ERROR(fs_info))
 		return -EROFS;
 
 	/* Seed devices of a new filesystem has their own generation. */

fs/btrfs/super.c

@@ -2006,7 +2006,7 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data)
 		if (ret)
 			goto restore;
 	} else {
-		if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
+		if (BTRFS_FS_ERROR(fs_info)) {
 			btrfs_err(fs_info,
 				"Remounting read-write after error is not allowed");
 			ret = -EINVAL;

fs/btrfs/transaction.c

@@ -283,7 +283,7 @@ static noinline int join_transaction(struct btrfs_fs_info *fs_info,
 	spin_lock(&fs_info->trans_lock);
 loop:
 	/* The file system has been taken offline. No new transactions. */
-	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
+	if (BTRFS_FS_ERROR(fs_info)) {
 		spin_unlock(&fs_info->trans_lock);
 		return -EROFS;
 	}
@@ -331,7 +331,7 @@ static noinline int join_transaction(struct btrfs_fs_info *fs_info,
 		 */
 		kfree(cur_trans);
 		goto loop;
-	} else if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
+	} else if (BTRFS_FS_ERROR(fs_info)) {
 		spin_unlock(&fs_info->trans_lock);
 		kfree(cur_trans);
 		return -EROFS;
@@ -579,7 +579,7 @@ start_transaction(struct btrfs_root *root, unsigned int num_items,
 	bool do_chunk_alloc = false;
 	int ret;
 
-	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
+	if (BTRFS_FS_ERROR(fs_info))
 		return ERR_PTR(-EROFS);
 
 	if (current->journal_info) {
@@ -991,8 +991,7 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
 	if (throttle)
 		btrfs_run_delayed_iputs(info);
 
-	if (TRANS_ABORTED(trans) ||
-	    test_bit(BTRFS_FS_STATE_ERROR, &info->fs_state)) {
+	if (TRANS_ABORTED(trans) || BTRFS_FS_ERROR(info)) {
 		wake_up_process(info->transaction_kthread);
 		if (TRANS_ABORTED(trans))
 			err = trans->aborted;
@@ -2155,7 +2154,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
 		 * abort to prevent writing a new superblock that reflects a
 		 * corrupt state (pointing to trees with unwritten nodes/leafs).
 		 */
-		if (test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state)) {
+		if (BTRFS_FS_ERROR(fs_info)) {
 			ret = -EROFS;
 			goto cleanup_transaction;
 		}

fs/btrfs/tree-log.c

@@ -3353,7 +3353,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	 * writing the super here would result in transid mismatches.  If there
 	 * is an error here just bail.
 	 */
-	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
+	if (BTRFS_FS_ERROR(fs_info)) {
 		ret = -EIO;
 		btrfs_set_log_full_commit(trans);
 		btrfs_abort_transaction(trans, ret);