From 07a191f762a7b8d0db13c38036380927116e29bb Mon Sep 17 00:00:00 2001
From: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Date: Fri, 25 Aug 2017 17:18:12 -0500
Subject: [PATCH] scsi: cxlflash: Fix vlun resize failure in the shrink path
References: fate#322239
Patch-mainline: v4.14-rc1
Git-commit: 07a191f762a7b8d0db13c38036380927116e29bb
The ioctl DK_CAPI_VLUN_RESIZE can fail if the allocated vlun size is
reduced from almost maximum capacity and then increased again.
The shrink_lxt() routine is currently using the SISL_ASTATUS_MASK to
mask the higher 48 bits of the lxt entry. This is unnecessary and
incorrect as it uses a mask designed for the asynchronous interrupt
status register. When the 4 port support was added to cxlflash, the
SISL_ASTATUS_MASK was updated to reflect the status bits for all 4
ports. This change indirectly affected the shrink_lxt() code path.
To extract the base, simply shift the bits without masking.
Fixes: 565180723294 ("scsi: cxlflash: SISlite updates to support 4 ports")
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
drivers/scsi/cxlflash/vlun.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/scsi/cxlflash/vlun.c b/drivers/scsi/cxlflash/vlun.c
index bdfb93061460..703bf1e9a64a 100644
--- a/drivers/scsi/cxlflash/vlun.c
+++ b/drivers/scsi/cxlflash/vlun.c
@@ -694,11 +694,7 @@ static int shrink_lxt(struct afu *afu,
/* Free LBAs allocated to freed chunks */
mutex_lock(&blka->mutex);
for (i = delta - 1; i >= 0; i--) {
- /* Mask the higher 48 bits before shifting, even though
- * it is a noop
- */
- aun = (lxt_old[my_new_size + i].rlba_base & SISL_ASTATUS_MASK);
- aun = (aun >> MC_CHUNK_SHIFT);
+ aun = lxt_old[my_new_size + i].rlba_base >> MC_CHUNK_SHIFT;
if (needs_ws)
write_same16(sdev, aun, MC_CHUNK_SIZE);
ba_free(&blka->ba_lun, aun);
--
2.10.2