Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/g…

…it/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Two current fixes:

   - one affects Qemu CD ROM emulation, which stopped working after the
     updates in SCSI to require VPD pages from all conformant devices.

     Fix temporarily by blacklisting Qemu (we can relax later when they
     come into compliance).

   - The other is a fix to the optimal transfer size.  We set up a
     minefield for ourselves by being confused about whether the limits
     are in bytes or sectors (SCSI optimal is in blocks and the queue
     parameter is in bytes).

     This tries to fix the problem (wrong setting for queue limits
     max_sectors) and make the problem more obvious by introducing a
     wrapper function"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  sd: Fix rw_max for devices that report an optimal xfer size
  scsi: Add QEMU CD-ROM to VPD Inquiry Blacklist

drivers/scsi/scsi_devinfo.c

@@ -230,6 +230,7 @@ static struct {
 	{"PIONEER", "CD-ROM DRM-624X", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
 	{"Promise", "VTrak E610f", NULL, BLIST_SPARSELUN | BLIST_NO_RSOC},
 	{"Promise", "", NULL, BLIST_SPARSELUN},
+	{"QEMU", "QEMU CD-ROM", NULL, BLIST_SKIP_VPD_PAGES},
 	{"QNAP", "iSCSI Storage", NULL, BLIST_MAX_1024},
 	{"SYNOLOGY", "iSCSI Storage", NULL, BLIST_MAX_1024},
 	{"QUANTUM", "XP34301", "1071", BLIST_NOTQ},

drivers/scsi/sd.c

@@ -2867,10 +2867,10 @@ static int sd_revalidate_disk(struct gendisk *disk)
 	if (sdkp->opt_xfer_blocks &&
 	    sdkp->opt_xfer_blocks <= dev_max &&
 	    sdkp->opt_xfer_blocks <= SD_DEF_XFER_BLOCKS &&
-	    sdkp->opt_xfer_blocks * sdp->sector_size >= PAGE_SIZE)
-		rw_max = q->limits.io_opt =
-			sdkp->opt_xfer_blocks * sdp->sector_size;
-	else
+	    logical_to_bytes(sdp, sdkp->opt_xfer_blocks) >= PAGE_SIZE) {
+		q->limits.io_opt = logical_to_bytes(sdp, sdkp->opt_xfer_blocks);
+		rw_max = logical_to_sectors(sdp, sdkp->opt_xfer_blocks);
+	} else
 		rw_max = BLK_DEF_MAX_SECTORS;
 
 	/* Combine with controller limits */

drivers/scsi/sd.h

@@ -151,6 +151,11 @@ static inline sector_t logical_to_sectors(struct scsi_device *sdev, sector_t blo
 	return blocks << (ilog2(sdev->sector_size) - 9);
 }
 
+static inline unsigned int logical_to_bytes(struct scsi_device *sdev, sector_t blocks)
+{
+	return blocks * sdev->sector_size;
+}
+
 /*
  * A DIF-capable target device can be formatted with different
  * protection schemes.  Currently 0 through 3 are defined: