scsi: provide general-purpose functions to manage sense data
Extract the common parts of scsi_sense_buf_to_errno, scsi_convert_sense
and scsi_target_send_command's REQUEST SENSE handling into two new
functions scsi_parse_sense_buf and scsi_build_sense_buf.
Fix a bug in scsi_target_send_command along the way; the length was
written in buf[10] rather than buf[7].
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes: b07fbce634 ("scsi-bus: correct responses for INQUIRY and REQUEST SENSE")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/scsi/utils.c b/scsi/utils.c
index e4182a9..61bc1a8 100644
--- a/scsi/utils.c
+++ b/scsi/utils.c
@@ -96,15 +96,60 @@
return cdb_len;
}
+SCSISense scsi_parse_sense_buf(const uint8_t *in_buf, int in_len)
+{
+ bool fixed_in;
+ SCSISense sense;
+
+ assert(in_len > 0);
+ fixed_in = (in_buf[0] & 2) == 0;
+ if (fixed_in) {
+ if (in_len < 14) {
+ return SENSE_CODE(IO_ERROR);
+ }
+ sense.key = in_buf[2];
+ sense.asc = in_buf[12];
+ sense.ascq = in_buf[13];
+ } else {
+ if (in_len < 4) {
+ return SENSE_CODE(IO_ERROR);
+ }
+ sense.key = in_buf[1];
+ sense.asc = in_buf[2];
+ sense.ascq = in_buf[3];
+ }
+
+ return sense;
+}
+
+int scsi_build_sense_buf(uint8_t *out_buf, size_t size, SCSISense sense,
+ bool fixed_sense)
+{
+ int len;
+ uint8_t buf[SCSI_SENSE_LEN] = { 0 };
+
+ if (fixed_sense) {
+ buf[0] = 0x70;
+ buf[2] = sense.key;
+ buf[7] = 10;
+ buf[12] = sense.asc;
+ buf[13] = sense.ascq;
+ len = 18;
+ } else {
+ buf[0] = 0x72;
+ buf[1] = sense.key;
+ buf[2] = sense.asc;
+ buf[3] = sense.ascq;
+ len = 8;
+ }
+ len = MIN(len, size);
+ memcpy(out_buf, buf, len);
+ return len;
+}
+
int scsi_build_sense(uint8_t *buf, SCSISense sense)
{
- memset(buf, 0, 18);
- buf[0] = 0x70;
- buf[2] = sense.key;
- buf[7] = 10;
- buf[12] = sense.asc;
- buf[13] = sense.ascq;
- return 18;
+ return scsi_build_sense_buf(buf, SCSI_SENSE_LEN, sense, true);
}
/*
@@ -274,52 +319,21 @@
int scsi_convert_sense(uint8_t *in_buf, int in_len,
uint8_t *buf, int len, bool fixed)
{
- bool fixed_in;
SCSISense sense;
- if (!fixed && len < 8) {
- return 0;
+ bool fixed_in;
+
+ fixed_in = (in_buf[0] & 2) == 0;
+ if (in_len && fixed == fixed_in) {
+ memcpy(buf, in_buf, MIN(len, in_len));
+ return MIN(len, in_len);
}
if (in_len == 0) {
- sense.key = NO_SENSE;
- sense.asc = 0;
- sense.ascq = 0;
+ sense = SENSE_CODE(NO_SENSE);
} else {
- fixed_in = (in_buf[0] & 2) == 0;
-
- if (fixed == fixed_in) {
- memcpy(buf, in_buf, MIN(len, in_len));
- return MIN(len, in_len);
- }
-
- if (fixed_in) {
- sense.key = in_buf[2];
- sense.asc = in_buf[12];
- sense.ascq = in_buf[13];
- } else {
- sense.key = in_buf[1];
- sense.asc = in_buf[2];
- sense.ascq = in_buf[3];
- }
+ sense = scsi_parse_sense_buf(in_buf, in_len);
}
-
- memset(buf, 0, len);
- if (fixed) {
- /* Return fixed format sense buffer */
- buf[0] = 0x70;
- buf[2] = sense.key;
- buf[7] = 10;
- buf[12] = sense.asc;
- buf[13] = sense.ascq;
- return MIN(len, SCSI_SENSE_LEN);
- } else {
- /* Return descriptor format sense buffer */
- buf[0] = 0x72;
- buf[1] = sense.key;
- buf[2] = sense.asc;
- buf[3] = sense.ascq;
- return 8;
- }
+ return scsi_build_sense_buf(buf, len, sense, fixed);
}
int scsi_sense_to_errno(int key, int asc, int ascq)
@@ -366,34 +380,15 @@
}
}
-int scsi_sense_buf_to_errno(const uint8_t *sense, size_t sense_size)
+int scsi_sense_buf_to_errno(const uint8_t *in_buf, size_t in_len)
{
- int key, asc, ascq;
- if (sense_size < 1) {
+ SCSISense sense;
+ if (in_len < 1) {
return EIO;
}
- switch (sense[0]) {
- case 0x70: /* Fixed format sense data. */
- if (sense_size < 14) {
- return EIO;
- }
- key = sense[2] & 0xF;
- asc = sense[12];
- ascq = sense[13];
- break;
- case 0x72: /* Descriptor format sense data. */
- if (sense_size < 4) {
- return EIO;
- }
- key = sense[1] & 0xF;
- asc = sense[2];
- ascq = sense[3];
- break;
- default:
- return EIO;
- break;
- }
- return scsi_sense_to_errno(key, asc, ascq);
+
+ sense = scsi_parse_sense_buf(in_buf, in_len);
+ return scsi_sense_to_errno(sense.key, sense.asc, sense.ascq);
}
const char *scsi_command_name(uint8_t cmd)
