We've had some discussions about what to do in certain scenarios for
error codes, specifically -EUCLEAN and -EROFS. Document these near the
error handling code so its clear what their intentions are.
Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
---
fs/btrfs/super.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 58f890f73650..688d1ab95b2b 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -67,6 +67,21 @@ static struct file_system_type btrfs_root_fs_type;
static int btrfs_remount(struct super_block *sb, int *flags, char *data);
+/*
+ * Generally the error codes correspond to their respective errors, but there's
+ * a few special cases.
+ *
+ * -EUCLEAN: Any sort of corruption that we encounter. The tree-checker for
+ * instance will return -EUCLEAN if any of the blocks are corrupted in a way
+ * that is problematic. We want to reserve -EUCLEAN for these sort of
+ * corruptions.
+ *
+ * -EROFS: If we check BTRFS_FS_STATE_ERROR and fail out with a return error, we
+ * need to use -EROFS for this case. We will have no idea of the original
+ * failure, that will have been reported at the time we tripped over the error.
+ * Each subsequent error that doesn't have any context of the original error
+ * should use -EROFS when handling BTRFS_FS_STATE_ERROR.
+ */
const char * __attribute_const__ btrfs_decode_error(int errno)
{
char *errstr = "unknown";
--
2.24.1
