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 vmbus_get_interface(&storvsc_drv_obj->Base.VmbusChannelInterface);
146 storvsc_drv_obj->RingBufferSize = storvsc_ringbuffer_size;
148 /* Callback to client driver to complete the initialization */
149 drv_init(&storvsc_drv_obj->Base);
151 DPRINT_INFO(STORVSC_DRV,
152 "request extension size %u, max outstanding reqs %u",
153 storvsc_drv_obj->RequestExtSize,
154 storvsc_drv_obj->MaxOutstandingRequestsPerChannel);
156 if (storvsc_drv_obj->MaxOutstandingRequestsPerChannel <
157 STORVSC_MAX_IO_REQUESTS) {
158 DPRINT_ERR(STORVSC_DRV,
159 "The number of outstanding io requests (%d) "
160 "is larger than that supported (%d) internally.",
161 STORVSC_MAX_IO_REQUESTS,
162 storvsc_drv_obj->MaxOutstandingRequestsPerChannel);
166 drv_ctx->driver.name = storvsc_drv_obj->Base.name;
167 memcpy(&drv_ctx->class_id, &storvsc_drv_obj->Base.deviceType,
168 sizeof(struct hv_guid));
170 drv_ctx->probe = storvsc_probe;
171 drv_ctx->remove = storvsc_remove;
173 /* The driver belongs to vmbus */
174 ret = vmbus_child_driver_register(drv_ctx);
179 static int storvsc_drv_exit_cb(struct device *dev, void *data)
181 struct device **curr = (struct device **)data;
183 return 1; /* stop iterating */
186 static void storvsc_drv_exit(void)
188 struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj;
189 struct driver_context *drv_ctx = &g_storvsc_drv.drv_ctx;
190 struct device *current_dev = NULL;
197 ret = driver_for_each_device(&drv_ctx->driver, NULL,
198 (void *) ¤t_dev,
199 storvsc_drv_exit_cb);
202 DPRINT_WARN(STORVSC_DRV,
203 "driver_for_each_device returned %d", ret);
205 if (current_dev == NULL)
208 /* Initiate removal from the top-down */
209 device_unregister(current_dev);
212 if (storvsc_drv_obj->Base.OnCleanup)
213 storvsc_drv_obj->Base.OnCleanup(&storvsc_drv_obj->Base);
215 vmbus_child_driver_unregister(drv_ctx);
220 * storvsc_probe - Add a new device for this driver
222 static int storvsc_probe(struct device *device)
225 struct driver_context *driver_ctx =
226 driver_to_driver_context(device->driver);
227 struct storvsc_driver_context *storvsc_drv_ctx =
228 (struct storvsc_driver_context *)driver_ctx;
229 struct storvsc_driver_object *storvsc_drv_obj =
230 &storvsc_drv_ctx->drv_obj;
231 struct vm_device *device_ctx = device_to_vm_device(device);
232 struct hv_device *device_obj = &device_ctx->device_obj;
233 struct Scsi_Host *host;
234 struct host_device_context *host_device_ctx;
235 struct storvsc_device_info device_info;
237 if (!storvsc_drv_obj->Base.OnDeviceAdd)
240 host = scsi_host_alloc(&scsi_driver,
241 sizeof(struct host_device_context));
243 DPRINT_ERR(STORVSC_DRV, "unable to allocate scsi host object");
247 dev_set_drvdata(device, host);
249 host_device_ctx = (struct host_device_context *)host->hostdata;
250 memset(host_device_ctx, 0, sizeof(struct host_device_context));
252 host_device_ctx->port = host->host_no;
253 host_device_ctx->device_ctx = device_ctx;
255 host_device_ctx->request_pool =
256 kmem_cache_create(dev_name(&device_ctx->device),
257 sizeof(struct storvsc_cmd_request) +
258 storvsc_drv_obj->RequestExtSize, 0,
259 SLAB_HWCACHE_ALIGN, NULL);
261 if (!host_device_ctx->request_pool) {
266 device_info.PortNumber = host->host_no;
267 /* Call to the vsc driver to add the device */
268 ret = storvsc_drv_obj->Base.OnDeviceAdd(device_obj,
269 (void *)&device_info);
271 DPRINT_ERR(STORVSC_DRV, "unable to add scsi vsc device");
272 kmem_cache_destroy(host_device_ctx->request_pool);
277 /* host_device_ctx->port = device_info.PortNumber; */
278 host_device_ctx->path = device_info.PathId;
279 host_device_ctx->target = device_info.TargetId;
281 /* max # of devices per target */
282 host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
283 /* max # of targets per channel */
284 host->max_id = STORVSC_MAX_TARGETS;
285 /* max # of channels */
286 host->max_channel = STORVSC_MAX_CHANNELS - 1;
288 /* Register the HBA and start the scsi bus scan */
289 ret = scsi_add_host(host, device);
291 DPRINT_ERR(STORVSC_DRV, "unable to add scsi host device");
293 storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
295 kmem_cache_destroy(host_device_ctx->request_pool);
300 scsi_scan_host(host);
305 * storvsc_remove - Callback when our device is removed
307 static int storvsc_remove(struct device *device)
310 struct driver_context *driver_ctx =
311 driver_to_driver_context(device->driver);
312 struct storvsc_driver_context *storvsc_drv_ctx =
313 (struct storvsc_driver_context *)driver_ctx;
314 struct storvsc_driver_object *storvsc_drv_obj =
315 &storvsc_drv_ctx->drv_obj;
316 struct vm_device *device_ctx = device_to_vm_device(device);
317 struct hv_device *device_obj = &device_ctx->device_obj;
318 struct Scsi_Host *host = dev_get_drvdata(device);
319 struct host_device_context *host_device_ctx =
320 (struct host_device_context *)host->hostdata;
323 if (!storvsc_drv_obj->Base.OnDeviceRemove)
327 * Call to the vsc driver to let it know that the device is being
330 ret = storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
333 DPRINT_ERR(STORVSC, "unable to remove vsc device (ret %d)",
337 if (host_device_ctx->request_pool) {
338 kmem_cache_destroy(host_device_ctx->request_pool);
339 host_device_ctx->request_pool = NULL;
342 DPRINT_INFO(STORVSC, "removing host adapter (%p)...", host);
343 scsi_remove_host(host);
345 DPRINT_INFO(STORVSC, "releasing host adapter (%p)...", host);
351 * storvsc_commmand_completion - Command completion processing
353 static void storvsc_commmand_completion(struct hv_storvsc_request *request)
355 struct storvsc_cmd_request *cmd_request =
356 (struct storvsc_cmd_request *)request->Context;
357 struct scsi_cmnd *scmnd = cmd_request->cmd;
358 struct host_device_context *host_device_ctx =
359 (struct host_device_context *)scmnd->device->host->hostdata;
360 void (*scsi_done_fn)(struct scsi_cmnd *);
361 struct scsi_sense_hdr sense_hdr;
363 /* ASSERT(request == &cmd_request->request); */
365 /* ASSERT((unsigned long)scmnd->host_scribble == */
366 /* (unsigned long)cmd_request); */
367 /* ASSERT(scmnd->scsi_done); */
369 if (cmd_request->bounce_sgl_count) {
370 /* using bounce buffer */
371 /* printk("copy_from_bounce_buffer\n"); */
373 /* FIXME: We can optimize on writes by just skipping this */
374 copy_from_bounce_buffer(scsi_sglist(scmnd),
375 cmd_request->bounce_sgl,
376 scsi_sg_count(scmnd));
377 destroy_bounce_buffer(cmd_request->bounce_sgl,
378 cmd_request->bounce_sgl_count);
381 scmnd->result = request->Status;
384 if (scsi_normalize_sense(scmnd->sense_buffer,
385 request->SenseBufferSize, &sense_hdr))
386 scsi_print_sense_hdr("storvsc", &sense_hdr);
389 /* ASSERT(request->BytesXfer <= request->DataBuffer.Length); */
390 scsi_set_resid(scmnd, request->DataBuffer.Length - request->BytesXfer);
392 scsi_done_fn = scmnd->scsi_done;
394 scmnd->host_scribble = NULL;
395 scmnd->scsi_done = NULL;
397 /* !!DO NOT MODIFY the scmnd after this call */
400 kmem_cache_free(host_device_ctx->request_pool, cmd_request);
403 static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
407 /* No need to check */
411 /* We have at least 2 sg entries */
412 for (i = 0; i < sg_count; i++) {
414 /* make sure 1st one does not have hole */
415 if (sgl[i].offset + sgl[i].length != PAGE_SIZE)
417 } else if (i == sg_count - 1) {
418 /* make sure last one does not have hole */
419 if (sgl[i].offset != 0)
422 /* make sure no hole in the middle */
423 if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0)
430 static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
431 unsigned int sg_count,
436 struct scatterlist *bounce_sgl;
437 struct page *page_buf;
439 num_pages = ALIGN_UP(len, PAGE_SIZE) >> PAGE_SHIFT;
441 bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
445 for (i = 0; i < num_pages; i++) {
446 page_buf = alloc_page(GFP_ATOMIC);
449 sg_set_page(&bounce_sgl[i], page_buf, 0, 0);
455 destroy_bounce_buffer(bounce_sgl, num_pages);
459 static void destroy_bounce_buffer(struct scatterlist *sgl,
460 unsigned int sg_count)
463 struct page *page_buf;
465 for (i = 0; i < sg_count; i++) {
466 page_buf = sg_page((&sgl[i]));
467 if (page_buf != NULL)
468 __free_page(page_buf);
474 /* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */
475 static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
476 struct scatterlist *bounce_sgl,
477 unsigned int orig_sgl_count)
481 unsigned long src, dest;
482 unsigned int srclen, destlen, copylen;
483 unsigned int total_copied = 0;
484 unsigned long bounce_addr = 0;
485 unsigned long src_addr = 0;
488 local_irq_save(flags);
490 for (i = 0; i < orig_sgl_count; i++) {
491 src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
492 KM_IRQ0) + orig_sgl[i].offset;
494 srclen = orig_sgl[i].length;
496 /* ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE); */
498 if (bounce_addr == 0)
499 bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
502 /* assume bounce offset always == 0 */
503 dest = bounce_addr + bounce_sgl[j].length;
504 destlen = PAGE_SIZE - bounce_sgl[j].length;
506 copylen = min(srclen, destlen);
507 memcpy((void *)dest, (void *)src, copylen);
509 total_copied += copylen;
510 bounce_sgl[j].length += copylen;
514 if (bounce_sgl[j].length == PAGE_SIZE) {
515 /* full..move to next entry */
516 kunmap_atomic((void *)bounce_addr, KM_IRQ0);
519 /* if we need to use another bounce buffer */
520 if (srclen || i != orig_sgl_count - 1)
521 bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
522 } else if (srclen == 0 && i == orig_sgl_count - 1) {
523 /* unmap the last bounce that is < PAGE_SIZE */
524 kunmap_atomic((void *)bounce_addr, KM_IRQ0);
528 kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0);
531 local_irq_restore(flags);
536 /* Assume the original sgl has enough room */
537 static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
538 struct scatterlist *bounce_sgl,
539 unsigned int orig_sgl_count)
543 unsigned long src, dest;
544 unsigned int srclen, destlen, copylen;
545 unsigned int total_copied = 0;
546 unsigned long bounce_addr = 0;
547 unsigned long dest_addr = 0;
550 local_irq_save(flags);
552 for (i = 0; i < orig_sgl_count; i++) {
553 dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
554 KM_IRQ0) + orig_sgl[i].offset;
556 destlen = orig_sgl[i].length;
557 /* ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE); */
559 if (bounce_addr == 0)
560 bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
563 src = bounce_addr + bounce_sgl[j].offset;
564 srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
566 copylen = min(srclen, destlen);
567 memcpy((void *)dest, (void *)src, copylen);
569 total_copied += copylen;
570 bounce_sgl[j].offset += copylen;
574 if (bounce_sgl[j].offset == bounce_sgl[j].length) {
576 kunmap_atomic((void *)bounce_addr, KM_IRQ0);
579 /* if we need to use another bounce buffer */
580 if (destlen || i != orig_sgl_count - 1)
581 bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
582 } else if (destlen == 0 && i == orig_sgl_count - 1) {
583 /* unmap the last bounce that is < PAGE_SIZE */
584 kunmap_atomic((void *)bounce_addr, KM_IRQ0);
588 kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset),
592 local_irq_restore(flags);
598 * storvsc_queuecommand - Initiate command processing
600 static int storvsc_queuecommand(struct scsi_cmnd *scmnd,
601 void (*done)(struct scsi_cmnd *))
604 struct host_device_context *host_device_ctx =
605 (struct host_device_context *)scmnd->device->host->hostdata;
606 struct vm_device *device_ctx = host_device_ctx->device_ctx;
607 struct driver_context *driver_ctx =
608 driver_to_driver_context(device_ctx->device.driver);
609 struct storvsc_driver_context *storvsc_drv_ctx =
610 (struct storvsc_driver_context *)driver_ctx;
611 struct storvsc_driver_object *storvsc_drv_obj =
612 &storvsc_drv_ctx->drv_obj;
613 struct hv_storvsc_request *request;
614 struct storvsc_cmd_request *cmd_request;
615 unsigned int request_size = 0;
617 struct scatterlist *sgl;
618 unsigned int sg_count = 0;
620 DPRINT_DBG(STORVSC_DRV, "scmnd %p dir %d, use_sg %d buf %p len %d "
621 "queue depth %d tagged %d", scmnd, scmnd->sc_data_direction,
622 scsi_sg_count(scmnd), scsi_sglist(scmnd),
623 scsi_bufflen(scmnd), scmnd->device->queue_depth,
624 scmnd->device->tagged_supported);
626 /* If retrying, no need to prep the cmd */
627 if (scmnd->host_scribble) {
628 /* ASSERT(scmnd->scsi_done != NULL); */
631 (struct storvsc_cmd_request *)scmnd->host_scribble;
632 DPRINT_INFO(STORVSC_DRV, "retrying scmnd %p cmd_request %p",
638 /* ASSERT(scmnd->scsi_done == NULL); */
639 /* ASSERT(scmnd->host_scribble == NULL); */
641 scmnd->scsi_done = done;
643 request_size = sizeof(struct storvsc_cmd_request);
645 cmd_request = kmem_cache_alloc(host_device_ctx->request_pool,
648 DPRINT_ERR(STORVSC_DRV, "scmnd (%p) - unable to allocate "
649 "storvsc_cmd_request...marking queue busy", scmnd);
650 scmnd->scsi_done = NULL;
651 return SCSI_MLQUEUE_DEVICE_BUSY;
654 /* Setup the cmd request */
655 cmd_request->bounce_sgl_count = 0;
656 cmd_request->bounce_sgl = NULL;
657 cmd_request->cmd = scmnd;
659 scmnd->host_scribble = (unsigned char *)cmd_request;
661 request = &cmd_request->request;
664 (void *)((unsigned long)cmd_request + request_size);
665 DPRINT_DBG(STORVSC_DRV, "req %p size %d ext %d", request, request_size,
666 storvsc_drv_obj->RequestExtSize);
669 switch (scmnd->sc_data_direction) {
671 request->Type = WRITE_TYPE;
673 case DMA_FROM_DEVICE:
674 request->Type = READ_TYPE;
677 request->Type = UNKNOWN_TYPE;
681 request->OnIOCompletion = storvsc_commmand_completion;
682 request->Context = cmd_request;/* scmnd; */
684 /* request->PortId = scmnd->device->channel; */
685 request->Host = host_device_ctx->port;
686 request->Bus = scmnd->device->channel;
687 request->TargetId = scmnd->device->id;
688 request->LunId = scmnd->device->lun;
690 /* ASSERT(scmnd->cmd_len <= 16); */
691 request->CdbLen = scmnd->cmd_len;
692 request->Cdb = scmnd->cmnd;
694 request->SenseBuffer = scmnd->sense_buffer;
695 request->SenseBufferSize = SCSI_SENSE_BUFFERSIZE;
698 request->DataBuffer.Length = scsi_bufflen(scmnd);
699 if (scsi_sg_count(scmnd)) {
700 sgl = (struct scatterlist *)scsi_sglist(scmnd);
701 sg_count = scsi_sg_count(scmnd);
703 /* check if we need to bounce the sgl */
704 if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) {
705 DPRINT_INFO(STORVSC_DRV,
706 "need to bounce buffer for this scmnd %p",
708 cmd_request->bounce_sgl =
709 create_bounce_buffer(sgl, scsi_sg_count(scmnd),
710 scsi_bufflen(scmnd));
711 if (!cmd_request->bounce_sgl) {
712 DPRINT_ERR(STORVSC_DRV,
713 "unable to create bounce buffer for "
714 "this scmnd %p", scmnd);
716 scmnd->scsi_done = NULL;
717 scmnd->host_scribble = NULL;
718 kmem_cache_free(host_device_ctx->request_pool,
721 return SCSI_MLQUEUE_HOST_BUSY;
724 cmd_request->bounce_sgl_count =
725 ALIGN_UP(scsi_bufflen(scmnd), PAGE_SIZE) >>
729 * FIXME: We can optimize on reads by just skipping
732 copy_to_bounce_buffer(sgl, cmd_request->bounce_sgl,
733 scsi_sg_count(scmnd));
735 sgl = cmd_request->bounce_sgl;
736 sg_count = cmd_request->bounce_sgl_count;
739 request->DataBuffer.Offset = sgl[0].offset;
741 for (i = 0; i < sg_count; i++) {
742 DPRINT_DBG(STORVSC_DRV, "sgl[%d] len %d offset %d\n",
743 i, sgl[i].length, sgl[i].offset);
744 request->DataBuffer.PfnArray[i] =
745 page_to_pfn(sg_page((&sgl[i])));
747 } else if (scsi_sglist(scmnd)) {
748 /* ASSERT(scsi_bufflen(scmnd) <= PAGE_SIZE); */
749 request->DataBuffer.Offset =
750 virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
751 request->DataBuffer.PfnArray[0] =
752 virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
756 /* Invokes the vsc to start an IO */
757 ret = storvsc_drv_obj->OnIORequest(&device_ctx->device_obj,
758 &cmd_request->request);
761 DPRINT_ERR(STORVSC_DRV,
762 "scmnd (%p) - queue FULL...marking queue busy",
765 if (cmd_request->bounce_sgl_count) {
767 * FIXME: We can optimize on writes by just skipping
770 copy_from_bounce_buffer(scsi_sglist(scmnd),
771 cmd_request->bounce_sgl,
772 scsi_sg_count(scmnd));
773 destroy_bounce_buffer(cmd_request->bounce_sgl,
774 cmd_request->bounce_sgl_count);
777 kmem_cache_free(host_device_ctx->request_pool, cmd_request);
779 scmnd->scsi_done = NULL;
780 scmnd->host_scribble = NULL;
782 ret = SCSI_MLQUEUE_DEVICE_BUSY;
788 static int storvsc_merge_bvec(struct request_queue *q,
789 struct bvec_merge_data *bmd, struct bio_vec *bvec)
791 /* checking done by caller. */
796 * storvsc_device_configure - Configure the specified scsi device
798 static int storvsc_device_alloc(struct scsi_device *sdevice)
800 DPRINT_DBG(STORVSC_DRV, "sdev (%p) - setting device flag to %d",
801 sdevice, BLIST_SPARSELUN);
803 * This enables luns to be located sparsely. Otherwise, we may not
806 sdevice->sdev_bflags |= BLIST_SPARSELUN | BLIST_LARGELUN;
810 static int storvsc_device_configure(struct scsi_device *sdevice)
812 DPRINT_INFO(STORVSC_DRV, "sdev (%p) - curr queue depth %d", sdevice,
813 sdevice->queue_depth);
815 DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting queue depth to %d",
816 sdevice, STORVSC_MAX_IO_REQUESTS);
817 scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG,
818 STORVSC_MAX_IO_REQUESTS);
820 DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting max segment size to %ld",
822 blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
824 DPRINT_INFO(STORVSC_DRV, "sdev (%p) - adding merge bio vec routine",
826 blk_queue_merge_bvec(sdevice->request_queue, storvsc_merge_bvec);
828 blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
829 /* sdevice->timeout = (2000 * HZ);//(75 * HZ); */
835 * storvsc_host_reset_handler - Reset the scsi HBA
837 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
840 struct host_device_context *host_device_ctx =
841 (struct host_device_context *)scmnd->device->host->hostdata;
842 struct vm_device *device_ctx = host_device_ctx->device_ctx;
844 DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host resetting...",
845 scmnd->device, &device_ctx->device_obj);
847 /* Invokes the vsc to reset the host/bus */
848 ret = StorVscOnHostReset(&device_ctx->device_obj);
852 DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host reseted",
853 scmnd->device, &device_ctx->device_obj);
858 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
859 sector_t capacity, int *info)
861 sector_t total_sectors = capacity;
862 sector_t cylinder_times_heads = 0;
865 int sectors_per_track = 0;
870 if (total_sectors > (65535 * 16 * 255))
871 total_sectors = (65535 * 16 * 255);
873 if (total_sectors >= (65535 * 16 * 63)) {
874 sectors_per_track = 255;
877 cylinder_times_heads = total_sectors;
878 /* sector_div stores the quotient in cylinder_times_heads */
879 rem = sector_div(cylinder_times_heads, sectors_per_track);
881 sectors_per_track = 17;
883 cylinder_times_heads = total_sectors;
884 /* sector_div stores the quotient in cylinder_times_heads */
885 rem = sector_div(cylinder_times_heads, sectors_per_track);
887 temp = cylinder_times_heads + 1023;
888 /* sector_div stores the quotient in temp */
889 rem = sector_div(temp, 1024);
896 if (cylinder_times_heads >= (heads * 1024) || (heads > 16)) {
897 sectors_per_track = 31;
900 cylinder_times_heads = total_sectors;
902 * sector_div stores the quotient in
903 * cylinder_times_heads
905 rem = sector_div(cylinder_times_heads,
909 if (cylinder_times_heads >= (heads * 1024)) {
910 sectors_per_track = 63;
913 cylinder_times_heads = total_sectors;
915 * sector_div stores the quotient in
916 * cylinder_times_heads
918 rem = sector_div(cylinder_times_heads,
923 temp = cylinder_times_heads;
924 /* sector_div stores the quotient in temp */
925 rem = sector_div(temp, heads);
929 info[1] = sectors_per_track;
932 DPRINT_INFO(STORVSC_DRV, "CHS (%d, %d, %d)", cylinders, heads,
938 static int __init storvsc_init(void)
942 DPRINT_INFO(STORVSC_DRV, "Storvsc initializing....");
943 ret = storvsc_drv_init(StorVscInitialize);
947 static void __exit storvsc_exit(void)
952 MODULE_LICENSE("GPL");
953 MODULE_VERSION(HV_DRV_VERSION);
954 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
955 module_init(storvsc_init);
956 module_exit(storvsc_exit);