> -----Original Message----- > From: Christoph Hellwig [mailto:hch@xxxxxx] > Sent: Monday, December 29, 2014 8:05 PM > To: KY Srinivasan; Haiyang Zhang; JBottomley@xxxxxxxxxxxxx > Cc: linux-scsi@xxxxxxxxxxxxxxx; devel@xxxxxxxxxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; Long Li; Christoph Hellwig > Subject: [PATCH] SCSI:STORVSC Use SCSI layer to allocate memory for per- > command device request data > > STORVSC uses its own momory pool to manage device request data. > However, SCSI layer already has a mechanisim for allocating additional > memory for each command issued to device driver. This patch removes the > memory pool in STORVSC and makes it use SCSI layer to allocate memory for > device request data. > > Reviewed-by: Long Li <longli@xxxxxxxxxxxxx> > Signed-off-by: Christoph Hellwig <hch@xxxxxx> Thanks Christoph. Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > --- > drivers/scsi/storvsc_drv.c | 119 +++------------------------------------------ > 1 file changed, 8 insertions(+), 111 deletions(-) > > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index > 4cff0dd..14ee98e 100644 > --- a/drivers/scsi/storvsc_drv.c > +++ b/drivers/scsi/storvsc_drv.c > @@ -32,7 +32,6 @@ > #include <linux/module.h> > #include <linux/device.h> > #include <linux/hyperv.h> > -#include <linux/mempool.h> > #include <linux/blkdev.h> > #include <scsi/scsi.h> > #include <scsi/scsi_cmnd.h> > @@ -309,14 +308,6 @@ enum storvsc_request_type { > * This is the end of Protocol specific defines. > */ > > - > -/* > - * We setup a mempool to allocate request structures for this driver > - * on a per-lun basis. The following define specifies the number of > - * elements in the pool. > - */ > - > -#define STORVSC_MIN_BUF_NR 64 > static int storvsc_ringbuffer_size = (20 * PAGE_SIZE); > > module_param(storvsc_ringbuffer_size, int, S_IRUGO); @@ -346,7 +337,6 > @@ static void storvsc_on_channel_callback(void *context); > #define STORVSC_IDE_MAX_CHANNELS 1 > > struct storvsc_cmd_request { > - struct list_head entry; > struct scsi_cmnd *cmd; > > unsigned int bounce_sgl_count; > @@ -357,7 +347,6 @@ struct storvsc_cmd_request { > /* Synchronize the request/response if needed */ > struct completion wait_event; > > - unsigned char *sense_buffer; > struct hv_multipage_buffer data_buffer; > struct vstor_packet vstor_packet; > }; > @@ -389,11 +378,6 @@ struct storvsc_device { > struct storvsc_cmd_request reset_request; }; > > -struct stor_mem_pools { > - struct kmem_cache *request_pool; > - mempool_t *request_mempool; > -}; > - > struct hv_host_device { > struct hv_device *dev; > unsigned int port; > @@ -1070,10 +1054,8 @@ static void storvsc_command_completion(struct > storvsc_cmd_request *cmd_request) { > struct scsi_cmnd *scmnd = cmd_request->cmd; > struct hv_host_device *host_dev = shost_priv(scmnd->device- > >host); > - void (*scsi_done_fn)(struct scsi_cmnd *); > struct scsi_sense_hdr sense_hdr; > struct vmscsi_request *vm_srb; > - struct stor_mem_pools *memp = scmnd->device->hostdata; > struct Scsi_Host *host; > struct storvsc_device *stor_dev; > struct hv_device *dev = host_dev->dev; @@ -1109,14 +1091,7 @@ > static void storvsc_command_completion(struct storvsc_cmd_request > *cmd_request) > cmd_request->data_buffer.len - > vm_srb->data_transfer_length); > > - scsi_done_fn = scmnd->scsi_done; > - > - scmnd->host_scribble = NULL; > - scmnd->scsi_done = NULL; > - > - scsi_done_fn(scmnd); > - > - mempool_free(cmd_request, memp->request_mempool); > + scmnd->scsi_done(scmnd); > } > > static void storvsc_on_io_completion(struct hv_device *device, @@ -1160,7 > +1135,7 @@ static void storvsc_on_io_completion(struct hv_device *device, > SRB_STATUS_AUTOSENSE_VALID) { > /* autosense data available */ > > - memcpy(request->sense_buffer, > + memcpy(request->cmd->sense_buffer, > vstor_packet->vm_srb.sense_data, > vstor_packet->vm_srb.sense_info_length); > > @@ -1378,55 +1353,6 @@ static int storvsc_do_io(struct hv_device *device, > return ret; > } > > -static int storvsc_device_alloc(struct scsi_device *sdevice) -{ > - struct stor_mem_pools *memp; > - int number = STORVSC_MIN_BUF_NR; > - > - memp = kzalloc(sizeof(struct stor_mem_pools), GFP_KERNEL); > - if (!memp) > - return -ENOMEM; > - > - memp->request_pool = > - kmem_cache_create(dev_name(&sdevice->sdev_dev), > - sizeof(struct storvsc_cmd_request), 0, > - SLAB_HWCACHE_ALIGN, NULL); > - > - if (!memp->request_pool) > - goto err0; > - > - memp->request_mempool = mempool_create(number, > mempool_alloc_slab, > - mempool_free_slab, > - memp->request_pool); > - > - if (!memp->request_mempool) > - goto err1; > - > - sdevice->hostdata = memp; > - > - return 0; > - > -err1: > - kmem_cache_destroy(memp->request_pool); > - > -err0: > - kfree(memp); > - return -ENOMEM; > -} > - > -static void storvsc_device_destroy(struct scsi_device *sdevice) -{ > - struct stor_mem_pools *memp = sdevice->hostdata; > - > - if (!memp) > - return; > - > - mempool_destroy(memp->request_mempool); > - kmem_cache_destroy(memp->request_pool); > - kfree(memp); > - sdevice->hostdata = NULL; > -} > - > static int storvsc_device_configure(struct scsi_device *sdevice) { > scsi_change_queue_depth(sdevice, STORVSC_MAX_IO_REQUESTS); > @@ -1561,13 +1487,11 @@ static int storvsc_queuecommand(struct > Scsi_Host *host, struct scsi_cmnd *scmnd) > int ret; > struct hv_host_device *host_dev = shost_priv(host); > struct hv_device *dev = host_dev->dev; > - struct storvsc_cmd_request *cmd_request; > - unsigned int request_size = 0; > + struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd); > int i; > struct scatterlist *sgl; > unsigned int sg_count = 0; > struct vmscsi_request *vm_srb; > - struct stor_mem_pools *memp = scmnd->device->hostdata; > > if (vmstor_current_major <= VMSTOR_WIN8_MAJOR) { > /* > @@ -1584,25 +1508,9 @@ static int storvsc_queuecommand(struct Scsi_Host > *host, struct scsi_cmnd *scmnd) > } > } > > - 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->cmd = scmnd; > > - scmnd->host_scribble = (unsigned char *)cmd_request; > - > vm_srb = &cmd_request->vstor_packet.vm_srb; > vm_srb->win8_extension.time_out_value = 60; > > @@ -1637,9 +1545,6 @@ static int storvsc_queuecommand(struct Scsi_Host > *host, struct scsi_cmnd *scmnd) > > memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length); > > - cmd_request->sense_buffer = scmnd->sense_buffer; > - > - > cmd_request->data_buffer.len = scsi_bufflen(scmnd); > if (scsi_sg_count(scmnd)) { > sgl = (struct scatterlist *)scsi_sglist(scmnd); @@ -1651,10 > +1556,8 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct > scsi_cmnd *scmnd) > create_bounce_buffer(sgl, > scsi_sg_count(scmnd), > scsi_bufflen(scmnd), > vm_srb->data_in); > - if (!cmd_request->bounce_sgl) { > - ret = SCSI_MLQUEUE_HOST_BUSY; > - goto queue_error; > - } > + if (!cmd_request->bounce_sgl) > + return SCSI_MLQUEUE_HOST_BUSY; > > cmd_request->bounce_sgl_count = > ALIGN(scsi_bufflen(scmnd), PAGE_SIZE) >> > @@ -1692,27 +1595,21 @@ static int storvsc_queuecommand(struct > Scsi_Host *host, struct scsi_cmnd *scmnd) > destroy_bounce_buffer(cmd_request->bounce_sgl, > cmd_request->bounce_sgl_count); > > - ret = SCSI_MLQUEUE_DEVICE_BUSY; > - goto queue_error; > + return SCSI_MLQUEUE_DEVICE_BUSY; > } > > return 0; > - > -queue_error: > - mempool_free(cmd_request, memp->request_mempool); > - scmnd->host_scribble = NULL; > - return ret; > } > > static struct scsi_host_template scsi_driver = { > .module = THIS_MODULE, > .name = "storvsc_host_t", > + .cmd_size = sizeof(struct storvsc_cmd_request), > .bios_param = storvsc_get_chs, > .queuecommand = storvsc_queuecommand, > .eh_host_reset_handler = storvsc_host_reset_handler, > + .proc_name = "storvsc_host", > .eh_timed_out = storvsc_eh_timed_out, > - .slave_alloc = storvsc_device_alloc, > - .slave_destroy = storvsc_device_destroy, > .slave_configure = storvsc_device_configure, > .cmd_per_lun = 255, > .can_queue = > STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS, > -- > 2.1.0 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
