[SCSI] Document enhanced error codes

Document the various error codes returned on I/O failure.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 124392f3091e..e2af8ae0d0ca 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -716,6 +716,18 @@ void scsi_release_buffers(struct scsi_cmnd *cmd)
 }
 EXPORT_SYMBOL(scsi_release_buffers);
 
+/**
+ * __scsi_error_from_host_byte - translate SCSI error code into errno
+ * @cmd:        SCSI command (unused)
+ * @result:     scsi error code
+ *
+ * Translate SCSI error code into standard UNIX errno.
+ * Return values:
+ * -ENOLINK     temporary transport failure
+ * -EREMOTEIO   permanent target failure, do not retry
+ * -EBADE       permanent nexus failure, retry on other path
+ * -EIO         unspecified I/O error
+ */
 static int __scsi_error_from_host_byte(struct scsi_cmnd *cmd, int result)
 {
         int error = 0;