scsi: vmw_pvscsi: Fix swiotlb operation

With swiotlb, the first byte of the sense buffer may in some cases be
uninitialized since we use DMA_FROM_DEVICE, and the device incorrectly
doesn't clear it. In those cases, clear it after DMA unmapping.

Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20191203193052.7583-1-thomas_os@shipmail.org
Suggested-by: Vishal Bhakta <vbhakta@vmware.com>
Acked-by: Jim Gill <jgill@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Thomas Hellstrom 2019-12-03 20:30:51 +01:00 committed by Martin K. Petersen
parent a808a04c86
commit f4652752a4

View File

@ -402,6 +402,17 @@ static int pvscsi_map_buffers(struct pvscsi_adapter *adapter,
return 0;
}
/*
* The device incorrectly doesn't clear the first byte of the sense
* buffer in some cases. We have to do it ourselves.
* Otherwise we run into trouble when SWIOTLB is forced.
*/
static void pvscsi_patch_sense(struct scsi_cmnd *cmd)
{
if (cmd->sense_buffer)
cmd->sense_buffer[0] = 0;
}
static void pvscsi_unmap_buffers(const struct pvscsi_adapter *adapter,
struct pvscsi_ctx *ctx)
{
@ -544,6 +555,8 @@ static void pvscsi_complete_request(struct pvscsi_adapter *adapter,
cmd = ctx->cmd;
abort_cmp = ctx->abort_cmp;
pvscsi_unmap_buffers(adapter, ctx);
if (sdstat != SAM_STAT_CHECK_CONDITION)
pvscsi_patch_sense(cmd);
pvscsi_release_context(adapter, ctx);
if (abort_cmp) {
/*
@ -873,6 +886,7 @@ static void pvscsi_reset_all(struct pvscsi_adapter *adapter)
scmd_printk(KERN_ERR, cmd,
"Forced reset on cmd %p\n", cmd);
pvscsi_unmap_buffers(adapter, ctx);
pvscsi_patch_sense(cmd);
pvscsi_release_context(adapter, ctx);
cmd->result = (DID_RESET << 16);
cmd->scsi_done(cmd);