diff mbox series

scsi: core: Make MODE SENSE DBD a boolean

Message ID 20200325213608.6843-1-martin.petersen@oracle.com (mailing list archive)
State Superseded
Headers show
Series scsi: core: Make MODE SENSE DBD a boolean | expand

Commit Message

Martin K. Petersen March 25, 2020, 9:36 p.m. UTC
The scsi_mode_sense() function has an argument called 'dbd' but
confusingly this is used to specify the entire second byte of the CDB
and not just the DBD bit.

Several callers assumed that 'dbd' was a flag and passed in a value of
1 instead of the required 8 to disable fetching block descriptors.
The invalid value of 1 was subsequently masked off by the function and
was not actually passed on to the device.

Turn the 'dbd' argument into a boolean and fix all callers.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
---
 drivers/scsi/scsi_lib.c           |  7 ++++---
 drivers/scsi/scsi_transport_sas.c |  2 +-
 drivers/scsi/sd.c                 | 14 +++++++-------
 drivers/scsi/sr.c                 |  2 +-
 include/scsi/scsi_device.h        |  2 +-
 5 files changed, 14 insertions(+), 13 deletions(-)

Comments

Bart Van Assche March 25, 2020, 9:45 p.m. UTC | #1
On 2020-03-25 14:36, Martin K. Petersen wrote:
>  	} else {
>  		modepage = 8;
> -		dbd = 0;
> +		dbd = true;
>  	}

Is this change on purpose? If so, please mention this as an intended
behavior change in the commit message.

Thanks,

Bart.
Martin K. Petersen March 25, 2020, 10:06 p.m. UTC | #2
Bart,

> On 2020-03-25 14:36, Martin K. Petersen wrote:
>>  	} else {
>>  		modepage = 8;
>> -		dbd = 0;
>> +		dbd = true;
>>  	}
>
> Is this change on purpose?

No, I probably triggered on the 8 in the modepage line above when I made
this change. Thanks for spotting!
diff mbox series

Patch

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 47835c4b4ee0..acbbdb022a45 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2085,7 +2085,7 @@  EXPORT_SYMBOL_GPL(scsi_mode_select);
  *	issued) if successful.
  */
 int
-scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
+scsi_mode_sense(struct scsi_device *sdev, bool dbd, int modepage,
 		  unsigned char *buffer, int len, int timeout, int retries,
 		  struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
 {
@@ -2098,8 +2098,9 @@  scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
 	memset(data, 0, sizeof(*data));
 	memset(&cmd[0], 0, 12);
 
-	dbd = sdev->set_dbd_for_ms ? 8 : dbd;
-	cmd[1] = dbd & 0x18;	/* allows DBD and LLBA bits */
+	dbd = sdev->set_dbd_for_ms ? true : dbd;
+	if (dbd)
+		cmd[1] = 1 << 3; /* DBD bit */
 	cmd[2] = modepage;
 
 	/* caller might not be interested in sense, but we need it */
diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c
index 182fd25c7c43..0547ccd81e84 100644
--- a/drivers/scsi/scsi_transport_sas.c
+++ b/drivers/scsi/scsi_transport_sas.c
@@ -1234,7 +1234,7 @@  int sas_read_port_mode_page(struct scsi_device *sdev)
 	if (!buffer)
 		return -ENOMEM;
 
-	res = scsi_mode_sense(sdev, 1, 0x19, buffer, BUF_SIZE, 30*HZ, 3,
+	res = scsi_mode_sense(sdev, true, 0x19, buffer, BUF_SIZE, 30*HZ, 3,
 			      &mode_data, NULL);
 
 	error = -EINVAL;
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 8ca9299ffd36..6093c1fc1d70 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -193,7 +193,7 @@  cache_type_store(struct device *dev, struct device_attribute *attr,
 		return count;
 	}
 
-	if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
+	if (scsi_mode_sense(sdp, true, 8, buffer, sizeof(buffer), SD_TIMEOUT,
 			    SD_MAX_RETRIES, &data, NULL))
 		return -EINVAL;
 	len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
@@ -2561,7 +2561,7 @@  sd_print_capacity(struct scsi_disk *sdkp,
 
 /* called with buffer of length 512 */
 static inline int
-sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
+sd_do_mode_sense(struct scsi_device *sdp, bool dbd, int modepage,
 		 unsigned char *buffer, int len, struct scsi_mode_data *data,
 		 struct scsi_sense_hdr *sshdr)
 {
@@ -2639,7 +2639,7 @@  sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
 	int len = 0, res;
 	struct scsi_device *sdp = sdkp->device;
 
-	int dbd;
+	bool dbd;
 	int modepage;
 	int first_len;
 	struct scsi_mode_data data;
@@ -2662,14 +2662,14 @@  sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
 			modepage = 0x3F;
 			if (sdp->use_192_bytes_for_3f)
 				first_len = 192;
-			dbd = 0;
+			dbd = false;
 		}
 	} else if (sdp->type == TYPE_RBC) {
 		modepage = 6;
-		dbd = 8;
+		dbd = true;
 	} else {
 		modepage = 8;
-		dbd = 0;
+		dbd = true;
 	}
 
 	/* cautiously ask */
@@ -2823,7 +2823,7 @@  static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
 	if (sdkp->protection_type == 0)
 		return;
 
-	res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
+	res = scsi_mode_sense(sdp, true, 0x0a, buffer, 36, SD_TIMEOUT,
 			      SD_MAX_RETRIES, &data, &sshdr);
 
 	if (!scsi_status_is_good(res) || !data.header_length ||
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index fe0e1c721a99..f31a946b7cd5 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -936,7 +936,7 @@  static void get_capabilities(struct scsi_cd *cd)
 	scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
 
 	/* ask for mode page 0x2a */
-	rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, ms_len,
+	rc = scsi_mode_sense(cd->device, false, 0x2a, buffer, ms_len,
 			     SR_TIMEOUT, 3, &data, NULL);
 
 	if (!scsi_status_is_good(rc) || data.length > ms_len ||
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index c3cba2aaf934..853082b7bcf6 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -397,7 +397,7 @@  extern int scsi_track_queue_full(struct scsi_device *, int);
 
 extern int scsi_set_medium_removal(struct scsi_device *, char);
 
-extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
+extern int scsi_mode_sense(struct scsi_device *sdev, bool dbd, int modepage,
 			   unsigned char *buffer, int len, int timeout,
 			   int retries, struct scsi_mode_data *data,
 			   struct scsi_sense_hdr *);