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
);