From c77b63b639f52b2e92d0bbaa94f33a78939f3e7c Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Thu, 12 Jan 2012 12:37:56 -0800 Subject: [PATCH] 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 Signed-off-by: Greg Kroah-Hartman --- drivers/staging/hv/storvsc_drv.c | 48 ++++++++++++++++++---------------------- 1 file changed, 22 insertions(+), 26 deletions(-) diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c index 7561d29..71e50c3 100644 --- a/drivers/staging/hv/storvsc_drv.c +++ b/drivers/staging/hv/storvsc_drv.c @@ -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; } -- 2.7.4