2 * Copyright (c) 2009, Microsoft Corporation.
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
21 #include <linux/init.h>
22 #include <linux/slab.h>
23 #include <linux/module.h>
24 #include <linux/device.h>
25 #include <linux/blkdev.h>
26 #include <scsi/scsi.h>
27 #include <scsi/scsi_cmnd.h>
28 #include <scsi/scsi_host.h>
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_tcq.h>
31 #include <scsi/scsi_eh.h>
32 #include <scsi/scsi_devinfo.h>
33 #include <scsi/scsi_dbg.h>
36 #include "version_info.h"
38 #include "storvsc_api.h"
41 struct host_device_context {
43 * FIXME this is a bug */
44 /* point back to our device context */
45 struct vm_device *device_ctx;
46 struct kmem_cache *request_pool;
52 struct storvsc_cmd_request {
53 struct list_head entry;
54 struct scsi_cmnd *cmd;
56 unsigned int bounce_sgl_count;
57 struct scatterlist *bounce_sgl;
59 struct hv_storvsc_request request;
60 /* !!!DO NOT ADD ANYTHING BELOW HERE!!! */
61 /* The extension buffer falls right here and is pointed to by
63 * Which sounds like a very bad design... */
66 struct storvsc_driver_context {
67 /* !! These must be the first 2 fields !! */
68 /* FIXME this is a bug... */
69 struct driver_context drv_ctx;
70 struct storvsc_driver_object drv_obj;
74 static int storvsc_probe(struct device *dev);
75 static int storvsc_queuecommand(struct scsi_cmnd *scmnd,
76 void (*done)(struct scsi_cmnd *));
77 static int storvsc_device_alloc(struct scsi_device *);
78 static int storvsc_device_configure(struct scsi_device *);
79 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd);
80 static int storvsc_remove(struct device *dev);
82 static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
83 unsigned int sg_count,
85 static void destroy_bounce_buffer(struct scatterlist *sgl,
86 unsigned int sg_count);
87 static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count);
88 static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
89 struct scatterlist *bounce_sgl,
90 unsigned int orig_sgl_count);
91 static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
92 struct scatterlist *bounce_sgl,
93 unsigned int orig_sgl_count);
95 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device *bdev,
96 sector_t capacity, int *info);
99 static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE;
100 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
101 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
103 /* The one and only one */
104 static struct storvsc_driver_context g_storvsc_drv;
107 static struct scsi_host_template scsi_driver = {
108 .module = THIS_MODULE,
109 .name = "storvsc_host_t",
110 .bios_param = storvsc_get_chs,
111 .queuecommand = storvsc_queuecommand,
112 .eh_host_reset_handler = storvsc_host_reset_handler,
113 .slave_alloc = storvsc_device_alloc,
114 .slave_configure = storvsc_device_configure,
116 /* 64 max_queue * 1 target */
117 .can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS,
119 /* no use setting to 0 since ll_blk_rw reset it to 1 */
121 .sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT,
123 * ENABLE_CLUSTERING allows mutiple physically contig bio_vecs to merge
124 * into 1 sg element. If set, we must limit the max_segment_size to
125 * PAGE_SIZE, otherwise we may get 1 sg element that represents
128 /* physically contig pfns (ie sg[x].length > PAGE_SIZE). */
129 .use_clustering = ENABLE_CLUSTERING,
130 /* Make sure we dont get a sg segment crosses a page boundary */
131 .dma_boundary = PAGE_SIZE-1,
136 * storvsc_drv_init - StorVsc driver initialization.
138 static int storvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
141 struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj;
142 struct driver_context *drv_ctx = &g_storvsc_drv.drv_ctx;
144 storvsc_drv_obj->RingBufferSize = storvsc_ringbuffer_size;
146 /* Callback to client driver to complete the initialization */
147 drv_init(&storvsc_drv_obj->Base);
149 DPRINT_INFO(STORVSC_DRV,
150 "request extension size %u, max outstanding reqs %u",
151 storvsc_drv_obj->RequestExtSize,
152 storvsc_drv_obj->MaxOutstandingRequestsPerChannel);
154 if (storvsc_drv_obj->MaxOutstandingRequestsPerChannel <
155 STORVSC_MAX_IO_REQUESTS) {
156 DPRINT_ERR(STORVSC_DRV,
157 "The number of outstanding io requests (%d) "
158 "is larger than that supported (%d) internally.",
159 STORVSC_MAX_IO_REQUESTS,
160 storvsc_drv_obj->MaxOutstandingRequestsPerChannel);
164 drv_ctx->driver.name = storvsc_drv_obj->Base.name;
165 memcpy(&drv_ctx->class_id, &storvsc_drv_obj->Base.deviceType,
166 sizeof(struct hv_guid));
168 drv_ctx->probe = storvsc_probe;
169 drv_ctx->remove = storvsc_remove;
171 /* The driver belongs to vmbus */
172 ret = vmbus_child_driver_register(drv_ctx);
177 static int storvsc_drv_exit_cb(struct device *dev, void *data)
179 struct device **curr = (struct device **)data;
181 return 1; /* stop iterating */
184 static void storvsc_drv_exit(void)
186 struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj;
187 struct driver_context *drv_ctx = &g_storvsc_drv.drv_ctx;
188 struct device *current_dev = NULL;
195 ret = driver_for_each_device(&drv_ctx->driver, NULL,
196 (void *) ¤t_dev,
197 storvsc_drv_exit_cb);
200 DPRINT_WARN(STORVSC_DRV,
201 "driver_for_each_device returned %d", ret);
203 if (current_dev == NULL)
206 /* Initiate removal from the top-down */
207 device_unregister(current_dev);
210 if (storvsc_drv_obj->Base.OnCleanup)
211 storvsc_drv_obj->Base.OnCleanup(&storvsc_drv_obj->Base);
213 vmbus_child_driver_unregister(drv_ctx);
218 * storvsc_probe - Add a new device for this driver
220 static int storvsc_probe(struct device *device)
223 struct driver_context *driver_ctx =
224 driver_to_driver_context(device->driver);
225 struct storvsc_driver_context *storvsc_drv_ctx =
226 (struct storvsc_driver_context *)driver_ctx;
227 struct storvsc_driver_object *storvsc_drv_obj =
228 &storvsc_drv_ctx->drv_obj;
229 struct vm_device *device_ctx = device_to_vm_device(device);
230 struct hv_device *device_obj = &device_ctx->device_obj;
231 struct Scsi_Host *host;
232 struct host_device_context *host_device_ctx;
233 struct storvsc_device_info device_info;
235 if (!storvsc_drv_obj->Base.OnDeviceAdd)
238 host = scsi_host_alloc(&scsi_driver,
239 sizeof(struct host_device_context));
241 DPRINT_ERR(STORVSC_DRV, "unable to allocate scsi host object");
245 dev_set_drvdata(device, host);
247 host_device_ctx = (struct host_device_context *)host->hostdata;
248 memset(host_device_ctx, 0, sizeof(struct host_device_context));
250 host_device_ctx->port = host->host_no;
251 host_device_ctx->device_ctx = device_ctx;
253 host_device_ctx->request_pool =
254 kmem_cache_create(dev_name(&device_ctx->device),
255 sizeof(struct storvsc_cmd_request) +
256 storvsc_drv_obj->RequestExtSize, 0,
257 SLAB_HWCACHE_ALIGN, NULL);
259 if (!host_device_ctx->request_pool) {
264 device_info.PortNumber = host->host_no;
265 /* Call to the vsc driver to add the device */
266 ret = storvsc_drv_obj->Base.OnDeviceAdd(device_obj,
267 (void *)&device_info);
269 DPRINT_ERR(STORVSC_DRV, "unable to add scsi vsc device");
270 kmem_cache_destroy(host_device_ctx->request_pool);
275 /* host_device_ctx->port = device_info.PortNumber; */
276 host_device_ctx->path = device_info.PathId;
277 host_device_ctx->target = device_info.TargetId;
279 /* max # of devices per target */
280 host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
281 /* max # of targets per channel */
282 host->max_id = STORVSC_MAX_TARGETS;
283 /* max # of channels */
284 host->max_channel = STORVSC_MAX_CHANNELS - 1;
286 /* Register the HBA and start the scsi bus scan */
287 ret = scsi_add_host(host, device);
289 DPRINT_ERR(STORVSC_DRV, "unable to add scsi host device");
291 storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
293 kmem_cache_destroy(host_device_ctx->request_pool);
298 scsi_scan_host(host);
303 * storvsc_remove - Callback when our device is removed
305 static int storvsc_remove(struct device *device)
308 struct driver_context *driver_ctx =
309 driver_to_driver_context(device->driver);
310 struct storvsc_driver_context *storvsc_drv_ctx =
311 (struct storvsc_driver_context *)driver_ctx;
312 struct storvsc_driver_object *storvsc_drv_obj =
313 &storvsc_drv_ctx->drv_obj;
314 struct vm_device *device_ctx = device_to_vm_device(device);
315 struct hv_device *device_obj = &device_ctx->device_obj;
316 struct Scsi_Host *host = dev_get_drvdata(device);
317 struct host_device_context *host_device_ctx =
318 (struct host_device_context *)host->hostdata;
321 if (!storvsc_drv_obj->Base.OnDeviceRemove)
325 * Call to the vsc driver to let it know that the device is being
328 ret = storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
331 DPRINT_ERR(STORVSC, "unable to remove vsc device (ret %d)",
335 if (host_device_ctx->request_pool) {
336 kmem_cache_destroy(host_device_ctx->request_pool);
337 host_device_ctx->request_pool = NULL;
340 DPRINT_INFO(STORVSC, "removing host adapter (%p)...", host);
341 scsi_remove_host(host);
343 DPRINT_INFO(STORVSC, "releasing host adapter (%p)...", host);
349 * storvsc_commmand_completion - Command completion processing
351 static void storvsc_commmand_completion(struct hv_storvsc_request *request)
353 struct storvsc_cmd_request *cmd_request =
354 (struct storvsc_cmd_request *)request->Context;
355 struct scsi_cmnd *scmnd = cmd_request->cmd;
356 struct host_device_context *host_device_ctx =
357 (struct host_device_context *)scmnd->device->host->hostdata;
358 void (*scsi_done_fn)(struct scsi_cmnd *);
359 struct scsi_sense_hdr sense_hdr;
361 /* ASSERT(request == &cmd_request->request); */
363 /* ASSERT((unsigned long)scmnd->host_scribble == */
364 /* (unsigned long)cmd_request); */
365 /* ASSERT(scmnd->scsi_done); */
367 if (cmd_request->bounce_sgl_count) {
368 /* using bounce buffer */
369 /* printk("copy_from_bounce_buffer\n"); */
371 /* FIXME: We can optimize on writes by just skipping this */
372 copy_from_bounce_buffer(scsi_sglist(scmnd),
373 cmd_request->bounce_sgl,
374 scsi_sg_count(scmnd));
375 destroy_bounce_buffer(cmd_request->bounce_sgl,
376 cmd_request->bounce_sgl_count);
379 scmnd->result = request->Status;
382 if (scsi_normalize_sense(scmnd->sense_buffer,
383 request->SenseBufferSize, &sense_hdr))
384 scsi_print_sense_hdr("storvsc", &sense_hdr);
387 /* ASSERT(request->BytesXfer <= request->DataBuffer.Length); */
388 scsi_set_resid(scmnd, request->DataBuffer.Length - request->BytesXfer);
390 scsi_done_fn = scmnd->scsi_done;
392 scmnd->host_scribble = NULL;
393 scmnd->scsi_done = NULL;
395 /* !!DO NOT MODIFY the scmnd after this call */
398 kmem_cache_free(host_device_ctx->request_pool, cmd_request);
401 static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
405 /* No need to check */
409 /* We have at least 2 sg entries */
410 for (i = 0; i < sg_count; i++) {
412 /* make sure 1st one does not have hole */
413 if (sgl[i].offset + sgl[i].length != PAGE_SIZE)
415 } else if (i == sg_count - 1) {
416 /* make sure last one does not have hole */
417 if (sgl[i].offset != 0)
420 /* make sure no hole in the middle */
421 if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0)
428 static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
429 unsigned int sg_count,
434 struct scatterlist *bounce_sgl;
435 struct page *page_buf;
437 num_pages = ALIGN_UP(len, PAGE_SIZE) >> PAGE_SHIFT;
439 bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
443 for (i = 0; i < num_pages; i++) {
444 page_buf = alloc_page(GFP_ATOMIC);
447 sg_set_page(&bounce_sgl[i], page_buf, 0, 0);
453 destroy_bounce_buffer(bounce_sgl, num_pages);
457 static void destroy_bounce_buffer(struct scatterlist *sgl,
458 unsigned int sg_count)
461 struct page *page_buf;
463 for (i = 0; i < sg_count; i++) {
464 page_buf = sg_page((&sgl[i]));
465 if (page_buf != NULL)
466 __free_page(page_buf);
472 /* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */
473 static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
474 struct scatterlist *bounce_sgl,
475 unsigned int orig_sgl_count)
479 unsigned long src, dest;
480 unsigned int srclen, destlen, copylen;
481 unsigned int total_copied = 0;
482 unsigned long bounce_addr = 0;
483 unsigned long src_addr = 0;
486 local_irq_save(flags);
488 for (i = 0; i < orig_sgl_count; i++) {
489 src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
490 KM_IRQ0) + orig_sgl[i].offset;
492 srclen = orig_sgl[i].length;
494 /* ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE); */
496 if (bounce_addr == 0)
497 bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
500 /* assume bounce offset always == 0 */
501 dest = bounce_addr + bounce_sgl[j].length;
502 destlen = PAGE_SIZE - bounce_sgl[j].length;
504 copylen = min(srclen, destlen);
505 memcpy((void *)dest, (void *)src, copylen);
507 total_copied += copylen;
508 bounce_sgl[j].length += copylen;
512 if (bounce_sgl[j].length == PAGE_SIZE) {
513 /* full..move to next entry */
514 kunmap_atomic((void *)bounce_addr, KM_IRQ0);
517 /* if we need to use another bounce buffer */
518 if (srclen || i != orig_sgl_count - 1)
519 bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
520 } else if (srclen == 0 && i == orig_sgl_count - 1) {
521 /* unmap the last bounce that is < PAGE_SIZE */
522 kunmap_atomic((void *)bounce_addr, KM_IRQ0);
526 kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0);
529 local_irq_restore(flags);
534 /* Assume the original sgl has enough room */
535 static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
536 struct scatterlist *bounce_sgl,
537 unsigned int orig_sgl_count)
541 unsigned long src, dest;
542 unsigned int srclen, destlen, copylen;
543 unsigned int total_copied = 0;
544 unsigned long bounce_addr = 0;
545 unsigned long dest_addr = 0;
548 local_irq_save(flags);
550 for (i = 0; i < orig_sgl_count; i++) {
551 dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
552 KM_IRQ0) + orig_sgl[i].offset;
554 destlen = orig_sgl[i].length;
555 /* ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE); */
557 if (bounce_addr == 0)
558 bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
561 src = bounce_addr + bounce_sgl[j].offset;
562 srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
564 copylen = min(srclen, destlen);
565 memcpy((void *)dest, (void *)src, copylen);
567 total_copied += copylen;
568 bounce_sgl[j].offset += copylen;
572 if (bounce_sgl[j].offset == bounce_sgl[j].length) {
574 kunmap_atomic((void *)bounce_addr, KM_IRQ0);
577 /* if we need to use another bounce buffer */
578 if (destlen || i != orig_sgl_count - 1)
579 bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
580 } else if (destlen == 0 && i == orig_sgl_count - 1) {
581 /* unmap the last bounce that is < PAGE_SIZE */
582 kunmap_atomic((void *)bounce_addr, KM_IRQ0);
586 kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset),
590 local_irq_restore(flags);
596 * storvsc_queuecommand - Initiate command processing
598 static int storvsc_queuecommand(struct scsi_cmnd *scmnd,
599 void (*done)(struct scsi_cmnd *))
602 struct host_device_context *host_device_ctx =
603 (struct host_device_context *)scmnd->device->host->hostdata;
604 struct vm_device *device_ctx = host_device_ctx->device_ctx;
605 struct driver_context *driver_ctx =
606 driver_to_driver_context(device_ctx->device.driver);
607 struct storvsc_driver_context *storvsc_drv_ctx =
608 (struct storvsc_driver_context *)driver_ctx;
609 struct storvsc_driver_object *storvsc_drv_obj =
610 &storvsc_drv_ctx->drv_obj;
611 struct hv_storvsc_request *request;
612 struct storvsc_cmd_request *cmd_request;
613 unsigned int request_size = 0;
615 struct scatterlist *sgl;
616 unsigned int sg_count = 0;
618 DPRINT_DBG(STORVSC_DRV, "scmnd %p dir %d, use_sg %d buf %p len %d "
619 "queue depth %d tagged %d", scmnd, scmnd->sc_data_direction,
620 scsi_sg_count(scmnd), scsi_sglist(scmnd),
621 scsi_bufflen(scmnd), scmnd->device->queue_depth,
622 scmnd->device->tagged_supported);
624 /* If retrying, no need to prep the cmd */
625 if (scmnd->host_scribble) {
626 /* ASSERT(scmnd->scsi_done != NULL); */
629 (struct storvsc_cmd_request *)scmnd->host_scribble;
630 DPRINT_INFO(STORVSC_DRV, "retrying scmnd %p cmd_request %p",
636 /* ASSERT(scmnd->scsi_done == NULL); */
637 /* ASSERT(scmnd->host_scribble == NULL); */
639 scmnd->scsi_done = done;
641 request_size = sizeof(struct storvsc_cmd_request);
643 cmd_request = kmem_cache_alloc(host_device_ctx->request_pool,
646 DPRINT_ERR(STORVSC_DRV, "scmnd (%p) - unable to allocate "
647 "storvsc_cmd_request...marking queue busy", scmnd);
648 scmnd->scsi_done = NULL;
649 return SCSI_MLQUEUE_DEVICE_BUSY;
652 /* Setup the cmd request */
653 cmd_request->bounce_sgl_count = 0;
654 cmd_request->bounce_sgl = NULL;
655 cmd_request->cmd = scmnd;
657 scmnd->host_scribble = (unsigned char *)cmd_request;
659 request = &cmd_request->request;
662 (void *)((unsigned long)cmd_request + request_size);
663 DPRINT_DBG(STORVSC_DRV, "req %p size %d ext %d", request, request_size,
664 storvsc_drv_obj->RequestExtSize);
667 switch (scmnd->sc_data_direction) {
669 request->Type = WRITE_TYPE;
671 case DMA_FROM_DEVICE:
672 request->Type = READ_TYPE;
675 request->Type = UNKNOWN_TYPE;
679 request->OnIOCompletion = storvsc_commmand_completion;
680 request->Context = cmd_request;/* scmnd; */
682 /* request->PortId = scmnd->device->channel; */
683 request->Host = host_device_ctx->port;
684 request->Bus = scmnd->device->channel;
685 request->TargetId = scmnd->device->id;
686 request->LunId = scmnd->device->lun;
688 /* ASSERT(scmnd->cmd_len <= 16); */
689 request->CdbLen = scmnd->cmd_len;
690 request->Cdb = scmnd->cmnd;
692 request->SenseBuffer = scmnd->sense_buffer;
693 request->SenseBufferSize = SCSI_SENSE_BUFFERSIZE;
696 request->DataBuffer.Length = scsi_bufflen(scmnd);
697 if (scsi_sg_count(scmnd)) {
698 sgl = (struct scatterlist *)scsi_sglist(scmnd);
699 sg_count = scsi_sg_count(scmnd);
701 /* check if we need to bounce the sgl */
702 if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) {
703 DPRINT_INFO(STORVSC_DRV,
704 "need to bounce buffer for this scmnd %p",
706 cmd_request->bounce_sgl =
707 create_bounce_buffer(sgl, scsi_sg_count(scmnd),
708 scsi_bufflen(scmnd));
709 if (!cmd_request->bounce_sgl) {
710 DPRINT_ERR(STORVSC_DRV,
711 "unable to create bounce buffer for "
712 "this scmnd %p", scmnd);
714 scmnd->scsi_done = NULL;
715 scmnd->host_scribble = NULL;
716 kmem_cache_free(host_device_ctx->request_pool,
719 return SCSI_MLQUEUE_HOST_BUSY;
722 cmd_request->bounce_sgl_count =
723 ALIGN_UP(scsi_bufflen(scmnd), PAGE_SIZE) >>
727 * FIXME: We can optimize on reads by just skipping
730 copy_to_bounce_buffer(sgl, cmd_request->bounce_sgl,
731 scsi_sg_count(scmnd));
733 sgl = cmd_request->bounce_sgl;
734 sg_count = cmd_request->bounce_sgl_count;
737 request->DataBuffer.Offset = sgl[0].offset;
739 for (i = 0; i < sg_count; i++) {
740 DPRINT_DBG(STORVSC_DRV, "sgl[%d] len %d offset %d\n",
741 i, sgl[i].length, sgl[i].offset);
742 request->DataBuffer.PfnArray[i] =
743 page_to_pfn(sg_page((&sgl[i])));
745 } else if (scsi_sglist(scmnd)) {
746 /* ASSERT(scsi_bufflen(scmnd) <= PAGE_SIZE); */
747 request->DataBuffer.Offset =
748 virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
749 request->DataBuffer.PfnArray[0] =
750 virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
754 /* Invokes the vsc to start an IO */
755 ret = storvsc_drv_obj->OnIORequest(&device_ctx->device_obj,
756 &cmd_request->request);
759 DPRINT_ERR(STORVSC_DRV,
760 "scmnd (%p) - queue FULL...marking queue busy",
763 if (cmd_request->bounce_sgl_count) {
765 * FIXME: We can optimize on writes by just skipping
768 copy_from_bounce_buffer(scsi_sglist(scmnd),
769 cmd_request->bounce_sgl,
770 scsi_sg_count(scmnd));
771 destroy_bounce_buffer(cmd_request->bounce_sgl,
772 cmd_request->bounce_sgl_count);
775 kmem_cache_free(host_device_ctx->request_pool, cmd_request);
777 scmnd->scsi_done = NULL;
778 scmnd->host_scribble = NULL;
780 ret = SCSI_MLQUEUE_DEVICE_BUSY;
786 static int storvsc_merge_bvec(struct request_queue *q,
787 struct bvec_merge_data *bmd, struct bio_vec *bvec)
789 /* checking done by caller. */
794 * storvsc_device_configure - Configure the specified scsi device
796 static int storvsc_device_alloc(struct scsi_device *sdevice)
798 DPRINT_DBG(STORVSC_DRV, "sdev (%p) - setting device flag to %d",
799 sdevice, BLIST_SPARSELUN);
801 * This enables luns to be located sparsely. Otherwise, we may not
804 sdevice->sdev_bflags |= BLIST_SPARSELUN | BLIST_LARGELUN;
808 static int storvsc_device_configure(struct scsi_device *sdevice)
810 DPRINT_INFO(STORVSC_DRV, "sdev (%p) - curr queue depth %d", sdevice,
811 sdevice->queue_depth);
813 DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting queue depth to %d",
814 sdevice, STORVSC_MAX_IO_REQUESTS);
815 scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG,
816 STORVSC_MAX_IO_REQUESTS);
818 DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting max segment size to %ld",
820 blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
822 DPRINT_INFO(STORVSC_DRV, "sdev (%p) - adding merge bio vec routine",
824 blk_queue_merge_bvec(sdevice->request_queue, storvsc_merge_bvec);
826 blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
827 /* sdevice->timeout = (2000 * HZ);//(75 * HZ); */
833 * storvsc_host_reset_handler - Reset the scsi HBA
835 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
838 struct host_device_context *host_device_ctx =
839 (struct host_device_context *)scmnd->device->host->hostdata;
840 struct vm_device *device_ctx = host_device_ctx->device_ctx;
842 DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host resetting...",
843 scmnd->device, &device_ctx->device_obj);
845 /* Invokes the vsc to reset the host/bus */
846 ret = StorVscOnHostReset(&device_ctx->device_obj);
850 DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host reseted",
851 scmnd->device, &device_ctx->device_obj);
856 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
857 sector_t capacity, int *info)
859 sector_t total_sectors = capacity;
860 sector_t cylinder_times_heads = 0;
863 int sectors_per_track = 0;
868 if (total_sectors > (65535 * 16 * 255))
869 total_sectors = (65535 * 16 * 255);
871 if (total_sectors >= (65535 * 16 * 63)) {
872 sectors_per_track = 255;
875 cylinder_times_heads = total_sectors;
876 /* sector_div stores the quotient in cylinder_times_heads */
877 rem = sector_div(cylinder_times_heads, sectors_per_track);
879 sectors_per_track = 17;
881 cylinder_times_heads = total_sectors;
882 /* sector_div stores the quotient in cylinder_times_heads */
883 rem = sector_div(cylinder_times_heads, sectors_per_track);
885 temp = cylinder_times_heads + 1023;
886 /* sector_div stores the quotient in temp */
887 rem = sector_div(temp, 1024);
894 if (cylinder_times_heads >= (heads * 1024) || (heads > 16)) {
895 sectors_per_track = 31;
898 cylinder_times_heads = total_sectors;
900 * sector_div stores the quotient in
901 * cylinder_times_heads
903 rem = sector_div(cylinder_times_heads,
907 if (cylinder_times_heads >= (heads * 1024)) {
908 sectors_per_track = 63;
911 cylinder_times_heads = total_sectors;
913 * sector_div stores the quotient in
914 * cylinder_times_heads
916 rem = sector_div(cylinder_times_heads,
921 temp = cylinder_times_heads;
922 /* sector_div stores the quotient in temp */
923 rem = sector_div(temp, heads);
927 info[1] = sectors_per_track;
930 DPRINT_INFO(STORVSC_DRV, "CHS (%d, %d, %d)", cylinders, heads,
936 static int __init storvsc_init(void)
940 DPRINT_INFO(STORVSC_DRV, "Storvsc initializing....");
941 ret = storvsc_drv_init(StorVscInitialize);
945 static void __exit storvsc_exit(void)
950 MODULE_LICENSE("GPL");
951 MODULE_VERSION(HV_DRV_VERSION);
952 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
953 module_init(storvsc_init);
954 module_exit(storvsc_exit);