[SCSI] libosd: Error handling revamped
Administer some love to the osd_req_decode_sense function
* Fix a bad bug with osd_req_decode_sense(). If there was no scsi
residual, .i.e the request never reached the target, then all the
osd_sense_info members where garbage.
* Add grossly missing in/out_resid to osd_sense_info and fill them in
properly.
* Define an osd_err_priority enum which divides the possible errors into
7 categories in ascending severity. Each category is also assigned a
Linux return code translation.
Analyze the different osd/scsi/block returned errors and set the
proper osd_err_priority and Linux return code accordingly.
* extra check a few situations so not to get stuck with inconsistent
error view. Example an empty residual with an error code, and other
places ...
Lots of libosd's osd_req_decode_sense clients had this logic in some
form or another. Consolidate all these into one place that should
actually know about osd returns. Thous translating it to a more
abstract error.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/include/scsi/osd_initiator.h b/include/scsi/osd_initiator.h
index 3ec346e..39d6d10 100644
--- a/include/scsi/osd_initiator.h
+++ b/include/scsi/osd_initiator.h
@@ -267,7 +267,7 @@
* @bad_attr_list - List of failing attributes (optional)
* @max_attr - Size of @bad_attr_list.
*
- * After execution, sense + return code can be analyzed using this function. The
+ * After execution, osd_request results are analyzed using this function. The
* return code is the final disposition on the error. So it is possible that a
* CHECK_CONDITION was returned from target but this will return NO_ERROR, for
* example on recovered errors. All parameters are optional if caller does
@@ -276,7 +276,31 @@
* of the SCSI_OSD_DPRINT_SENSE Kconfig value. Set @silent if you know the
* command would routinely fail, to not spam the dmsg file.
*/
+
+/**
+ * osd_err_priority - osd categorized return codes in ascending severity.
+ *
+ * The categories are borrowed from the pnfs_osd_errno enum.
+ * See comments for translated Linux codes returned by osd_req_decode_sense.
+ */
+enum osd_err_priority {
+ OSD_ERR_PRI_NO_ERROR = 0,
+ /* Recoverable, caller should clear_highpage() all pages */
+ OSD_ERR_PRI_CLEAR_PAGES = 1, /* -EFAULT */
+ OSD_ERR_PRI_RESOURCE = 2, /* -ENOMEM */
+ OSD_ERR_PRI_BAD_CRED = 3, /* -EINVAL */
+ OSD_ERR_PRI_NO_ACCESS = 4, /* -EACCES */
+ OSD_ERR_PRI_UNREACHABLE = 5, /* any other */
+ OSD_ERR_PRI_NOT_FOUND = 6, /* -ENOENT */
+ OSD_ERR_PRI_NO_SPACE = 7, /* -ENOSPC */
+ OSD_ERR_PRI_EIO = 8, /* -EIO */
+};
+
struct osd_sense_info {
+ u64 out_resid; /* Zero on success otherwise out residual */
+ u64 in_resid; /* Zero on success otherwise in residual */
+ enum osd_err_priority osd_err_pri;
+
int key; /* one of enum scsi_sense_keys */
int additional_code ; /* enum osd_additional_sense_codes */
union { /* Sense specific information */