If a driver returns:
DID_TARGET_FAILURE
DID_NEXUS_FAILURE
DID_ALLOC_FAILURE
DID_MEDIUM_ERROR
we hit a couple bugs:
1. The SCSI error handler runs because scsi_decide_disposition has no
case statements for them and we return FAILED.
2. For SG IO the userspace app gets a success status instead of failed,
because scsi_result_to_blk_status clears those errors.
This patch adds a new internal error code byte for use by scsi-ml. It
will be used instead of the above error codes, so we don't have to play
that clearing the host code game in scsi_result_to_blk_status and
drivers cannot accidentally use them.
The next patch will then remove the internal users of the above codes and
convert us to use the new ones.
Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
---
drivers/scsi/scsi_error.c | 5 +++++
drivers/scsi/scsi_lib.c | 22 ++++++++++++++++++++++
drivers/scsi/scsi_priv.h | 11 +++++++++++
3 files changed, 38 insertions(+)
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 947d98a0565f..4adadd3fb410 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -514,6 +514,11 @@ static void scsi_report_sense(struct scsi_device *sdev,
}
}
+static inline void set_scsi_ml_byte(struct scsi_cmnd *cmd, u8 status)
+{
+ cmd->result = (cmd->result & 0xffff00ff) | (status << 8);
+}
+
/**
* scsi_check_sense - Examine scsi cmd sense
* @scmd: Cmd to have sense checked.
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 2aca0a838ca5..eaf4865a2cb6 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -576,6 +576,11 @@ static bool scsi_end_request(struct request *req, blk_status_t error,
return false;
}
+static inline u8 get_scsi_ml_byte(int result)
+{
+ return (result >> 8) & 0xff;
+}
+
/**
* scsi_result_to_blk_status - translate a SCSI result code into blk_status_t
* @cmd: SCSI command
@@ -586,6 +591,23 @@ static bool scsi_end_request(struct request *req, blk_status_t error,
*/
static blk_status_t scsi_result_to_blk_status(struct scsi_cmnd *cmd, int result)
{
+ /*
+ * Check the scsi-ml byte first in case we converted a host or status
+ * byte.
+ */
+ switch (get_scsi_ml_byte(result)) {
+ case SCSIML_STAT_OK:
+ break;
+ case SCSIML_STAT_RESV_CONFLICT:
+ return BLK_STS_NEXUS;
+ case SCSIML_STAT_SPACE_ALLOC:
+ return BLK_STS_NOSPC;
+ case SCSIML_STAT_MED_ERROR:
+ return BLK_STS_MEDIUM;
+ case SCSIML_STAT_TGT_FAILURE:
+ return BLK_STS_TARGET;
+ }
+
switch (host_byte(result)) {
case DID_OK:
if (scsi_status_is_good(result))
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index 5c4786310a31..9d2d32bf0171 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -18,6 +18,17 @@ struct scsi_nl_hdr;
#define SCSI_CMD_RETRIES_NO_LIMIT -1
+/*
+ * Error codes used by scsi-ml internally. These must not be used by drivers.
+ */
+enum scsi_ml_status {
+ SCSIML_STAT_OK = 0x00,
+ SCSIML_STAT_RESV_CONFLICT = 0x01, /* Reservation conflict */
+ SCSIML_STAT_SPACE_ALLOC = 0x02, /* Space allocation on the dev failed */
+ SCSIML_STAT_MED_ERROR = 0x03, /* Medium error */
+ SCSIML_STAT_TGT_FAILURE = 0x04, /* Permanent target failure */
+};
+
/*
* Scsi Error Handler Flags
*/
--
2.25.1
