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
);