On Wed 30-06-21 15:46:35, Lukas Czerner wrote:

On Wed, Jun 16, 2021 at 12:56:55PM +0200, Jan Kara wrote:

quoted

@@ -28,28 +42,24 @@ static int ext4_orphan_file_add(handle_t *handle, struct inode *inode)
 		 */
 		return -ENOSPC;
 	}
-	oi->of_binfo[i].ob_free_entries--;
-	spin_unlock(&oi->of_lock);
 
-	/*
-	 * Get access to orphan block. We have dropped of_lock but since we
-	 * have decremented number of free entries we are guaranteed free entry
-	 * in our block.
-	 */
 	ret = ext4_journal_get_write_access(handle, inode->i_sb,
 				oi->of_binfo[i].ob_bh, EXT4_JTR_ORPHAN_FILE);
 	if (ret)
 		return ret;
 
 	bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
-	spin_lock(&oi->of_lock);
 	/* Find empty slot in a block */
-	for (j = 0; j < inodes_per_ob && bdata[j]; j++);
-	BUG_ON(j == inodes_per_ob);
-	bdata[j] = cpu_to_le32(inode->i_ino);
+	j = 0;
+	do {
+		while (bdata[j]) {
+			if (++j >= inodes_per_ob)
+				j = 0;
+		}
+	} while (cmpxchg(&bdata[j], 0, cpu_to_le32(inode->i_ino)) != 0);

In case there is any sort of corruption on disk or in memory we can
potentially get stuck here forever right ? Not sure if that matters
all that much.

Other than that it looks good and negates some of my comments on the
previous patch, sorry about that ;)

You can add

Reviewed-by: Lukas Czerner <redacted>

Good point. I've added some limitations (and cond_resched()) to the loop so
that we cannot loop indefinitely. Thanks for review!

								Honza
-- 
Jan Kara [off-list ref]
SUSE Labs, CR