scsi: Update sense code handling

The SCSI spec has a quite detailed list of sense codes available.
It even mandates the use of specific ones for some failure cases.
The current implementation just has one type of generic error
which is actually a violation of the spec in certain cases.
This patch introduces various predefined sense codes to have the
sense code reporting more in line with the spec.

On top of Hannes's patch I fixed the reply to REQUEST SENSE commands
with DESC=0 and a small (<18) length.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

1 files changed, 38 insertions, 1 deletions

diff --git a/hw/scsi.h b/hw/scsi.h
index e2dc7cb5e1..7a7c9efb57 100644
--- a/hw/scsi.h
+++ b/hw/scsi.h
@@ -27,6 +27,12 @@ enum SCSIXferMode {
     SCSI_XFER_TO_DEV,    /*  WRITE, MODE_SELECT, ...         */
 };
 
+typedef struct SCSISense {
+    uint8_t key;
+    uint8_t asc;
+    uint8_t ascq;
+} SCSISense;
+
 struct SCSIRequest {
     SCSIBus           *bus;
     SCSIDevice        *dev;
@@ -104,10 +110,41 @@ SCSIDevice *scsi_bus_legacy_add_drive(SCSIBus *bus, BlockDriverState *bdrv,
                                       int unit, bool removable);
 int scsi_bus_legacy_handle_cmdline(SCSIBus *bus);
 
+/*
+ * Predefined sense codes
+ */
+
+/* No sense data available */
+extern const struct SCSISense sense_code_NO_SENSE;
+/* LUN not ready, Manual intervention required */
+extern const struct SCSISense sense_code_LUN_NOT_READY;
+/* LUN not ready, Medium not present */
+extern const struct SCSISense sense_code_NO_MEDIUM;
+/* Hardware error, internal target failure */
+extern const struct SCSISense sense_code_TARGET_FAILURE;
+/* Illegal request, invalid command operation code */
+extern const struct SCSISense sense_code_INVALID_OPCODE;
+/* Illegal request, LBA out of range */
+extern const struct SCSISense sense_code_LBA_OUT_OF_RANGE;
+/* Illegal request, Invalid field in CDB */
+extern const struct SCSISense sense_code_INVALID_FIELD;
+/* Illegal request, LUN not supported */
+extern const struct SCSISense sense_code_LUN_NOT_SUPPORTED;
+/* Command aborted, I/O process terminated */
+extern const struct SCSISense sense_code_IO_ERROR;
+/* Command aborted, I_T Nexus loss occurred */
+extern const struct SCSISense sense_code_I_T_NEXUS_LOSS;
+/* Command aborted, Logical Unit failure */
+extern const struct SCSISense sense_code_LUN_FAILURE;
+
+#define SENSE_CODE(x) sense_code_ ## x
+
+int scsi_build_sense(SCSISense sense, uint8_t *buf, int len, int fixed);
+int scsi_sense_valid(SCSISense sense);
+
 SCSIRequest *scsi_req_alloc(size_t size, SCSIDevice *d, uint32_t tag, uint32_t lun);
 void scsi_req_enqueue(SCSIRequest *req);
 void scsi_req_free(SCSIRequest *req);
-void scsi_req_dequeue(SCSIRequest *req);
 SCSIRequest *scsi_req_ref(SCSIRequest *req);
 void scsi_req_unref(SCSIRequest *req);