| Message ID | 20240604144501.3862738-1-martin.petersen@oracle.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | scsi: sd: Use READ(16) when reading block zero on large capacity disks | expand |
On 6/4/24 08:45, Martin K. Petersen wrote: > static void sd_read_block_zero(struct scsi_disk *sdkp) > { > - unsigned int buf_len = sdkp->device->sector_size; > - char *buffer, cmd[10] = { }; > + struct scsi_device *sdev = sdkp->device; > + unsigned int buf_len = sdev->sector_size; > + char *buffer, cmd[16] = { }; Maybe this is a good opportunity to change 'char' into 'u8'? It seems a bit unusual to me to use signed char for a SCSI CDB and a data buffer. Otherwise this patch looks good to me. Thanks, Bart.
Hi Bart! > Maybe this is a good opportunity to change 'char' into 'u8'? It seems > a bit unusual to me to use signed char for a SCSI CDB and a data > buffer. It's not signed (-funsigned-char) but I can change it to u8. Martin
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 65cdc8b77e35..6759bd5af58a 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -3572,16 +3572,23 @@ static bool sd_validate_opt_xfer_size(struct scsi_disk *sdkp, static void sd_read_block_zero(struct scsi_disk *sdkp) { - unsigned int buf_len = sdkp->device->sector_size; - char *buffer, cmd[10] = { }; + struct scsi_device *sdev = sdkp->device; + unsigned int buf_len = sdev->sector_size; + char *buffer, cmd[16] = { }; buffer = kmalloc(buf_len, GFP_KERNEL); if (!buffer) return; - cmd[0] = READ_10; - put_unaligned_be32(0, &cmd[2]); /* Logical block address 0 */ - put_unaligned_be16(1, &cmd[7]); /* Transfer 1 logical block */ + if (sdev->use_16_for_rw) { + cmd[0] = READ_16; + put_unaligned_be64(0, &cmd[2]); /* Logical block address 0 */ + put_unaligned_be32(1, &cmd[10]);/* Transfer 1 logical block */ + } else { + cmd[0] = READ_10; + put_unaligned_be32(0, &cmd[2]); /* Logical block address 0 */ + put_unaligned_be16(1, &cmd[7]); /* Transfer 1 logical block */ + } scsi_execute_cmd(sdkp->device, cmd, REQ_OP_DRV_IN, buffer, buf_len, SD_TIMEOUT, sdkp->max_retries, NULL);
Commit 321da3dc1f3c ("scsi: sd: usb_storage: uas: Access media prior to querying device properties") triggered a read to LBA 0 before attempting to inquire about device characteristics. This was done because some protocol bridge devices will return generic values until an attached storage device's media has been accessed. Pierre Tomon reported that this change caused problems on a large capacity external drive connected via a bridge device. The bridge in question does not appear to implement the READ(10) command. Issue a READ(16) instead of READ(10) when a device has been identified as preferring 16-byte commands (use_16_for_rw heuristic). Cc: stable@vger.kernel.org Fixes: 321da3dc1f3c ("scsi: sd: usb_storage: uas: Access media prior to querying device properties") Link: https://bugzilla.kernel.org/show_bug.cgi?id=218890 Reported-by: Pierre Tomon <pierretom+12@ik.me> Suggested-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Pierre Tomon <pierretom+12@ik.me> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> --- drivers/scsi/sd.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)