Staging: hv: storvsc: Cleanup storvsc_queuecommand()

Cleanup storvsc_queuecommand(). As part of this cleanup, rename the function to
check if the scsi command can be sent to the host, consolidate error recovery
and get rid of some dead code.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
K. Y. Srinivasan 2012-01-12 12:37:56 -08:00 committed by Greg Kroah-Hartman
parent 59d22950b2
commit c77b63b639

View file

@ -1239,13 +1239,16 @@ static void storvsc_command_completion(struct hv_storvsc_request *request)
mempool_free(cmd_request, memp->request_mempool);
}
static bool storvsc_check_scsi_cmd(struct scsi_cmnd *scmnd)
static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
{
bool allowed = true;
u8 scsi_op = scmnd->cmnd[0];
switch (scsi_op) {
/* smartd sends this command, which will offline the device */
/*
* smartd sends this command and the host does not handle
* this. So, don't send it.
*/
case SET_WINDOW:
scmnd->result = ILLEGAL_REQUEST << 16;
allowed = false;
@ -1270,32 +1273,26 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
struct vmscsi_request *vm_srb;
struct stor_mem_pools *memp = scmnd->device->hostdata;
if (storvsc_check_scsi_cmd(scmnd) == false) {
if (!storvsc_scsi_cmd_ok(scmnd)) {
scmnd->scsi_done(scmnd);
return 0;
}
/* If retrying, no need to prep the cmd */
if (scmnd->host_scribble) {
cmd_request =
(struct storvsc_cmd_request *)scmnd->host_scribble;
goto retry_request;
}
request_size = sizeof(struct storvsc_cmd_request);
cmd_request = mempool_alloc(memp->request_mempool,
GFP_ATOMIC);
/*
* We might be invoked in an interrupt context; hence
* mempool_alloc() can fail.
*/
if (!cmd_request)
return SCSI_MLQUEUE_DEVICE_BUSY;
memset(cmd_request, 0, sizeof(struct storvsc_cmd_request));
/* Setup the cmd request */
cmd_request->bounce_sgl_count = 0;
cmd_request->bounce_sgl = NULL;
cmd_request->cmd = scmnd;
scmnd->host_scribble = (unsigned char *)cmd_request;
@ -1344,11 +1341,8 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
scsi_bufflen(scmnd),
vm_srb->data_in);
if (!cmd_request->bounce_sgl) {
scmnd->host_scribble = NULL;
mempool_free(cmd_request,
memp->request_mempool);
return SCSI_MLQUEUE_HOST_BUSY;
ret = SCSI_MLQUEUE_HOST_BUSY;
goto queue_error;
}
cmd_request->bounce_sgl_count =
@ -1377,24 +1371,26 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
}
retry_request:
/* Invokes the vsc to start an IO */
ret = storvsc_do_io(dev, &cmd_request->request);
if (ret == -EAGAIN) {
/* no more space */
if (cmd_request->bounce_sgl_count)
if (cmd_request->bounce_sgl_count) {
destroy_bounce_buffer(cmd_request->bounce_sgl,
cmd_request->bounce_sgl_count);
mempool_free(cmd_request, memp->request_mempool);
scmnd->host_scribble = NULL;
ret = SCSI_MLQUEUE_DEVICE_BUSY;
ret = SCSI_MLQUEUE_DEVICE_BUSY;
goto queue_error;
}
}
return 0;
queue_error:
mempool_free(cmd_request, memp->request_mempool);
scmnd->host_scribble = NULL;
return ret;
}