1 files changed, 25 insertions, 4 deletions

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 7b75c8a2a49d..829cc37abc41 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -49,6 +49,7 @@
 #include <linux/mutex.h>
 #include <linux/string_helpers.h>
 #include <linux/async.h>
+#include <linux/slab.h>
 #include <asm/uaccess.h>
 #include <asm/unaligned.h>
 
@@ -1039,6 +1040,7 @@ static void sd_prepare_flush(struct request_queue *q, struct request *rq)
 {
 	rq->cmd_type = REQ_TYPE_BLOCK_PC;
 	rq->timeout = SD_TIMEOUT;
+	rq->retries = SD_MAX_RETRIES;
 	rq->cmd[0] = SYNCHRONIZE_CACHE;
 	rq->cmd_len = 10;
 }
@@ -1432,6 +1434,8 @@ static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
 #error RC16_LEN must not be more than SD_BUF_SIZE
 #endif
 
+#define READ_CAPACITY_RETRIES_ON_RESET	10
+
 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
 						unsigned char *buffer)
 {
@@ -1439,7 +1443,7 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
 	struct scsi_sense_hdr sshdr;
 	int sense_valid = 0;
 	int the_result;
-	int retries = 3;
+	int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
 	unsigned int alignment;
 	unsigned long long lba;
 	unsigned sector_size;
@@ -1468,6 +1472,13 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
 				 * Invalid Field in CDB, just retry
 				 * silently with RC10 */
 				return -EINVAL;
+			if (sense_valid &&
+			    sshdr.sense_key == UNIT_ATTENTION &&
+			    sshdr.asc == 0x29 && sshdr.ascq == 0x00)
+				/* Device reset might occur several times,
+				 * give it one more chance */
+				if (--reset_retries > 0)
+					continue;
 		}
 		retries--;
 
@@ -1526,7 +1537,7 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
 	struct scsi_sense_hdr sshdr;
 	int sense_valid = 0;
 	int the_result;
-	int retries = 3;
+	int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
 	sector_t lba;
 	unsigned sector_size;
 
@@ -1542,8 +1553,16 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
 		if (media_not_present(sdkp, &sshdr))
 			return -ENODEV;
 
-		if (the_result)
+		if (the_result) {
 			sense_valid = scsi_sense_valid(&sshdr);
+			if (sense_valid &&
+			    sshdr.sense_key == UNIT_ATTENTION &&
+			    sshdr.asc == 0x29 && sshdr.ascq == 0x00)
+				/* Device reset might occur several times,
+				 * give it one more chance */
+				if (--reset_retries > 0)
+					continue;
+		}
 		retries--;
 
 	} while (the_result && retries);
@@ -1572,6 +1591,8 @@ static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
 
 static int sd_try_rc16_first(struct scsi_device *sdp)
 {
+	if (sdp->host->max_cmd_len < 16)
+		return 0;
 	if (sdp->scsi_level > SCSI_SPC_2)
 		return 1;
 	if (scsi_device_protection(sdp))
@@ -2185,7 +2206,7 @@ static void sd_probe_async(void *data, async_cookie_t cookie)
 	blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
 
 	gd->driverfs_dev = &sdp->sdev_gendev;
-	gd->flags = GENHD_FL_EXT_DEVT | GENHD_FL_DRIVERFS;
+	gd->flags = GENHD_FL_EXT_DEVT;
 	if (sdp->removable)
 		gd->flags |= GENHD_FL_REMOVABLE;