[PATCH 3/3] [SCSI] Make LBP quirk skip lbpme checks tests

[Sitsofe Wheeler <sitsofe@gmail.com>]

Some block devices (such as Hyper-V passthrough SSDs) support logical
block provisioning (e.g. via UNMAP) but don't set lbpme thus disabling
discard. If the try_lbp quirk is in use skip lbpme checks that lead up
to the logical block provisioning tests.

Signed-off-by: Sitsofe Wheeler <sitsofe@yahoo.com>
---
 drivers/scsi/sd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 8249e51..8bf34bc 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2559,7 +2559,7 @@ static void sd_read_block_limits(struct scsi_disk *sdkp)
 
 		sdkp->max_ws_blocks = (u32)get_unaligned_be64(&buffer[36]);
 
-		if (!sdkp->lbpme)
+		if (!sdkp->lbpme && !sdkp->device->try_lbp)
 			goto out;
 
 		lba_count = get_unaligned_be32(&buffer[20]);
@@ -2633,7 +2633,7 @@ static void sd_read_block_provisioning(struct scsi_disk *sdkp)
 	unsigned char *buffer;
 	const int vpd_len = 8;
 
-	if (sdkp->lbpme == 0)
+	if (sdkp->lbpme == 0 && sdkp->device->test_lbp == 0)
 		return;
 
 	buffer = kmalloc(vpd_len, GFP_KERNEL);
-- 
1.9.3