Staging: Merge branch 'staging-next' into 2.6.38-rc3
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / staging / hv / blkvsc_drv.c
blob58bbcd60b3d7ffb26922515d52e2d4d08a228e0b
1 /*
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
11 * more details.
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.
17 * Authors:
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
21 #include <linux/init.h>
22 #include <linux/module.h>
23 #include <linux/device.h>
24 #include <linux/blkdev.h>
25 #include <linux/major.h>
26 #include <linux/delay.h>
27 #include <linux/hdreg.h>
28 #include <linux/mutex.h>
29 #include <linux/slab.h>
30 #include <scsi/scsi.h>
31 #include <scsi/scsi_cmnd.h>
32 #include <scsi/scsi_eh.h>
33 #include <scsi/scsi_dbg.h>
34 #include "osd.h"
35 #include "logging.h"
36 #include "version_info.h"
37 #include "vmbus.h"
38 #include "storvsc_api.h"
41 #define BLKVSC_MINORS 64
43 enum blkvsc_device_type {
44 UNKNOWN_DEV_TYPE,
45 HARDDISK_TYPE,
46 DVD_TYPE,
50 * This request ties the struct request and struct
51 * blkvsc_request/hv_storvsc_request together A struct request may be
52 * represented by 1 or more struct blkvsc_request
54 struct blkvsc_request_group {
55 int outstanding;
56 int status;
57 struct list_head blkvsc_req_list; /* list of blkvsc_requests */
60 struct blkvsc_request {
61 /* blkvsc_request_group.blkvsc_req_list */
62 struct list_head req_entry;
64 /* block_device_context.pending_list */
65 struct list_head pend_entry;
67 /* This may be null if we generate a request internally */
68 struct request *req;
70 struct block_device_context *dev;
72 /* The group this request is part of. Maybe null */
73 struct blkvsc_request_group *group;
75 wait_queue_head_t wevent;
76 int cond;
78 int write;
79 sector_t sector_start;
80 unsigned long sector_count;
82 unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE];
83 unsigned char cmd_len;
84 unsigned char cmnd[MAX_COMMAND_SIZE];
86 struct hv_storvsc_request request;
88 * !!!DO NOT ADD ANYTHING BELOW HERE!!! Otherwise, memory can overlap,
89 * because - The extension buffer falls right here and is pointed to by
90 * request.Extension;
91 * Which sounds like a horrible idea, who designed this?
95 /* Per device structure */
96 struct block_device_context {
97 /* point back to our device context */
98 struct vm_device *device_ctx;
99 struct kmem_cache *request_pool;
100 spinlock_t lock;
101 struct gendisk *gd;
102 enum blkvsc_device_type device_type;
103 struct list_head pending_list;
105 unsigned char device_id[64];
106 unsigned int device_id_len;
107 int num_outstanding_reqs;
108 int shutting_down;
109 int media_not_present;
110 unsigned int sector_size;
111 sector_t capacity;
112 unsigned int port;
113 unsigned char path;
114 unsigned char target;
115 int users;
118 /* Per driver */
119 struct blkvsc_driver_context {
120 /* !! These must be the first 2 fields !! */
121 /* FIXME this is a bug! */
122 struct driver_context drv_ctx;
123 struct storvsc_driver_object drv_obj;
126 /* Static decl */
127 static DEFINE_MUTEX(blkvsc_mutex);
128 static int blkvsc_probe(struct device *dev);
129 static int blkvsc_remove(struct device *device);
130 static void blkvsc_shutdown(struct device *device);
132 static int blkvsc_open(struct block_device *bdev, fmode_t mode);
133 static int blkvsc_release(struct gendisk *disk, fmode_t mode);
134 static int blkvsc_media_changed(struct gendisk *gd);
135 static int blkvsc_revalidate_disk(struct gendisk *gd);
136 static int blkvsc_getgeo(struct block_device *bd, struct hd_geometry *hg);
137 static int blkvsc_ioctl(struct block_device *bd, fmode_t mode,
138 unsigned cmd, unsigned long argument);
139 static void blkvsc_request(struct request_queue *queue);
140 static void blkvsc_request_completion(struct hv_storvsc_request *request);
141 static int blkvsc_do_request(struct block_device_context *blkdev,
142 struct request *req);
143 static int blkvsc_submit_request(struct blkvsc_request *blkvsc_req,
144 void (*request_completion)(struct hv_storvsc_request *));
145 static void blkvsc_init_rw(struct blkvsc_request *blkvsc_req);
146 static void blkvsc_cmd_completion(struct hv_storvsc_request *request);
147 static int blkvsc_do_inquiry(struct block_device_context *blkdev);
148 static int blkvsc_do_read_capacity(struct block_device_context *blkdev);
149 static int blkvsc_do_read_capacity16(struct block_device_context *blkdev);
150 static int blkvsc_do_flush(struct block_device_context *blkdev);
151 static int blkvsc_cancel_pending_reqs(struct block_device_context *blkdev);
152 static int blkvsc_do_pending_reqs(struct block_device_context *blkdev);
154 static int blkvsc_ringbuffer_size = BLKVSC_RING_BUFFER_SIZE;
155 module_param(blkvsc_ringbuffer_size, int, S_IRUGO);
156 MODULE_PARM_DESC(ring_size, "Ring buffer size (in bytes)");
158 /* The one and only one */
159 static struct blkvsc_driver_context g_blkvsc_drv;
161 static const struct block_device_operations block_ops = {
162 .owner = THIS_MODULE,
163 .open = blkvsc_open,
164 .release = blkvsc_release,
165 .media_changed = blkvsc_media_changed,
166 .revalidate_disk = blkvsc_revalidate_disk,
167 .getgeo = blkvsc_getgeo,
168 .ioctl = blkvsc_ioctl,
172 * blkvsc_drv_init - BlkVsc driver initialization.
174 static int blkvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
176 struct storvsc_driver_object *storvsc_drv_obj = &g_blkvsc_drv.drv_obj;
177 struct driver_context *drv_ctx = &g_blkvsc_drv.drv_ctx;
178 int ret;
180 storvsc_drv_obj->ring_buffer_size = blkvsc_ringbuffer_size;
182 /* Callback to client driver to complete the initialization */
183 drv_init(&storvsc_drv_obj->base);
185 drv_ctx->driver.name = storvsc_drv_obj->base.name;
186 memcpy(&drv_ctx->class_id, &storvsc_drv_obj->base.dev_type,
187 sizeof(struct hv_guid));
189 drv_ctx->probe = blkvsc_probe;
190 drv_ctx->remove = blkvsc_remove;
191 drv_ctx->shutdown = blkvsc_shutdown;
193 /* The driver belongs to vmbus */
194 ret = vmbus_child_driver_register(drv_ctx);
196 return ret;
199 static int blkvsc_drv_exit_cb(struct device *dev, void *data)
201 struct device **curr = (struct device **)data;
202 *curr = dev;
203 return 1; /* stop iterating */
206 static void blkvsc_drv_exit(void)
208 struct storvsc_driver_object *storvsc_drv_obj = &g_blkvsc_drv.drv_obj;
209 struct driver_context *drv_ctx = &g_blkvsc_drv.drv_ctx;
210 struct device *current_dev;
211 int ret;
213 while (1) {
214 current_dev = NULL;
216 /* Get the device */
217 ret = driver_for_each_device(&drv_ctx->driver, NULL,
218 (void *) &current_dev,
219 blkvsc_drv_exit_cb);
221 if (ret)
222 DPRINT_WARN(BLKVSC_DRV,
223 "driver_for_each_device returned %d", ret);
226 if (current_dev == NULL)
227 break;
229 /* Initiate removal from the top-down */
230 device_unregister(current_dev);
233 if (storvsc_drv_obj->base.cleanup)
234 storvsc_drv_obj->base.cleanup(&storvsc_drv_obj->base);
236 vmbus_child_driver_unregister(drv_ctx);
238 return;
242 * blkvsc_probe - Add a new device for this driver
244 static int blkvsc_probe(struct device *device)
246 struct driver_context *driver_ctx =
247 driver_to_driver_context(device->driver);
248 struct blkvsc_driver_context *blkvsc_drv_ctx =
249 (struct blkvsc_driver_context *)driver_ctx;
250 struct storvsc_driver_object *storvsc_drv_obj =
251 &blkvsc_drv_ctx->drv_obj;
252 struct vm_device *device_ctx = device_to_vm_device(device);
253 struct hv_device *device_obj = &device_ctx->device_obj;
255 struct block_device_context *blkdev = NULL;
256 struct storvsc_device_info device_info;
257 int major = 0;
258 int devnum = 0;
259 int ret = 0;
260 static int ide0_registered;
261 static int ide1_registered;
263 DPRINT_DBG(BLKVSC_DRV, "blkvsc_probe - enter");
265 if (!storvsc_drv_obj->base.dev_add) {
266 DPRINT_ERR(BLKVSC_DRV, "OnDeviceAdd() not set");
267 ret = -1;
268 goto Cleanup;
271 blkdev = kzalloc(sizeof(struct block_device_context), GFP_KERNEL);
272 if (!blkdev) {
273 ret = -ENOMEM;
274 goto Cleanup;
277 INIT_LIST_HEAD(&blkdev->pending_list);
279 /* Initialize what we can here */
280 spin_lock_init(&blkdev->lock);
282 /* ASSERT(sizeof(struct blkvsc_request_group) <= */
283 /* sizeof(struct blkvsc_request)); */
285 blkdev->request_pool = kmem_cache_create(dev_name(&device_ctx->device),
286 sizeof(struct blkvsc_request) +
287 storvsc_drv_obj->request_ext_size, 0,
288 SLAB_HWCACHE_ALIGN, NULL);
289 if (!blkdev->request_pool) {
290 ret = -ENOMEM;
291 goto Cleanup;
295 /* Call to the vsc driver to add the device */
296 ret = storvsc_drv_obj->base.dev_add(device_obj, &device_info);
297 if (ret != 0) {
298 DPRINT_ERR(BLKVSC_DRV, "unable to add blkvsc device");
299 goto Cleanup;
302 blkdev->device_ctx = device_ctx;
303 /* this identified the device 0 or 1 */
304 blkdev->target = device_info.target_id;
305 /* this identified the ide ctrl 0 or 1 */
306 blkdev->path = device_info.path_id;
308 dev_set_drvdata(device, blkdev);
310 /* Calculate the major and device num */
311 if (blkdev->path == 0) {
312 major = IDE0_MAJOR;
313 devnum = blkdev->path + blkdev->target; /* 0 or 1 */
315 if (!ide0_registered) {
316 ret = register_blkdev(major, "ide");
317 if (ret != 0) {
318 DPRINT_ERR(BLKVSC_DRV,
319 "register_blkdev() failed! ret %d",
320 ret);
321 goto Remove;
324 ide0_registered = 1;
326 } else if (blkdev->path == 1) {
327 major = IDE1_MAJOR;
328 devnum = blkdev->path + blkdev->target + 1; /* 2 or 3 */
330 if (!ide1_registered) {
331 ret = register_blkdev(major, "ide");
332 if (ret != 0) {
333 DPRINT_ERR(BLKVSC_DRV,
334 "register_blkdev() failed! ret %d",
335 ret);
336 goto Remove;
339 ide1_registered = 1;
341 } else {
342 DPRINT_ERR(BLKVSC_DRV, "invalid pathid");
343 ret = -1;
344 goto Cleanup;
347 DPRINT_INFO(BLKVSC_DRV, "blkvsc registered for major %d!!", major);
349 blkdev->gd = alloc_disk(BLKVSC_MINORS);
350 if (!blkdev->gd) {
351 DPRINT_ERR(BLKVSC_DRV, "register_blkdev() failed! ret %d", ret);
352 ret = -1;
353 goto Cleanup;
356 blkdev->gd->queue = blk_init_queue(blkvsc_request, &blkdev->lock);
358 blk_queue_max_segment_size(blkdev->gd->queue, PAGE_SIZE);
359 blk_queue_max_segments(blkdev->gd->queue, MAX_MULTIPAGE_BUFFER_COUNT);
360 blk_queue_segment_boundary(blkdev->gd->queue, PAGE_SIZE-1);
361 blk_queue_bounce_limit(blkdev->gd->queue, BLK_BOUNCE_ANY);
362 blk_queue_dma_alignment(blkdev->gd->queue, 511);
364 blkdev->gd->major = major;
365 if (devnum == 1 || devnum == 3)
366 blkdev->gd->first_minor = BLKVSC_MINORS;
367 else
368 blkdev->gd->first_minor = 0;
369 blkdev->gd->fops = &block_ops;
370 blkdev->gd->private_data = blkdev;
371 blkdev->gd->driverfs_dev = &(blkdev->device_ctx->device);
372 sprintf(blkdev->gd->disk_name, "hd%c", 'a' + devnum);
374 blkvsc_do_inquiry(blkdev);
375 if (blkdev->device_type == DVD_TYPE) {
376 set_disk_ro(blkdev->gd, 1);
377 blkdev->gd->flags |= GENHD_FL_REMOVABLE;
378 blkvsc_do_read_capacity(blkdev);
379 } else {
380 blkvsc_do_read_capacity16(blkdev);
383 set_capacity(blkdev->gd, blkdev->capacity * (blkdev->sector_size/512));
384 blk_queue_logical_block_size(blkdev->gd->queue, blkdev->sector_size);
385 /* go! */
386 add_disk(blkdev->gd);
388 DPRINT_INFO(BLKVSC_DRV, "%s added!! capacity %lu sector_size %d",
389 blkdev->gd->disk_name, (unsigned long)blkdev->capacity,
390 blkdev->sector_size);
392 return ret;
394 Remove:
395 storvsc_drv_obj->base.dev_rm(device_obj);
397 Cleanup:
398 if (blkdev) {
399 if (blkdev->request_pool) {
400 kmem_cache_destroy(blkdev->request_pool);
401 blkdev->request_pool = NULL;
403 kfree(blkdev);
404 blkdev = NULL;
407 return ret;
410 static void blkvsc_shutdown(struct device *device)
412 struct block_device_context *blkdev = dev_get_drvdata(device);
413 unsigned long flags;
415 if (!blkdev)
416 return;
418 DPRINT_DBG(BLKVSC_DRV, "blkvsc_shutdown - users %d disk %s\n",
419 blkdev->users, blkdev->gd->disk_name);
421 spin_lock_irqsave(&blkdev->lock, flags);
423 blkdev->shutting_down = 1;
425 blk_stop_queue(blkdev->gd->queue);
427 spin_unlock_irqrestore(&blkdev->lock, flags);
429 while (blkdev->num_outstanding_reqs) {
430 DPRINT_INFO(STORVSC, "waiting for %d requests to complete...",
431 blkdev->num_outstanding_reqs);
432 udelay(100);
435 blkvsc_do_flush(blkdev);
437 spin_lock_irqsave(&blkdev->lock, flags);
439 blkvsc_cancel_pending_reqs(blkdev);
441 spin_unlock_irqrestore(&blkdev->lock, flags);
444 static int blkvsc_do_flush(struct block_device_context *blkdev)
446 struct blkvsc_request *blkvsc_req;
448 DPRINT_DBG(BLKVSC_DRV, "blkvsc_do_flush()\n");
450 if (blkdev->device_type != HARDDISK_TYPE)
451 return 0;
453 blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_KERNEL);
454 if (!blkvsc_req)
455 return -ENOMEM;
457 memset(blkvsc_req, 0, sizeof(struct blkvsc_request));
458 init_waitqueue_head(&blkvsc_req->wevent);
459 blkvsc_req->dev = blkdev;
460 blkvsc_req->req = NULL;
461 blkvsc_req->write = 0;
463 blkvsc_req->request.data_buffer.pfn_array[0] = 0;
464 blkvsc_req->request.data_buffer.offset = 0;
465 blkvsc_req->request.data_buffer.len = 0;
467 blkvsc_req->cmnd[0] = SYNCHRONIZE_CACHE;
468 blkvsc_req->cmd_len = 10;
471 * Set this here since the completion routine may be invoked and
472 * completed before we return
474 blkvsc_req->cond = 0;
475 blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
477 wait_event_interruptible(blkvsc_req->wevent, blkvsc_req->cond);
479 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
481 return 0;
484 /* Do a scsi INQUIRY cmd here to get the device type (ie disk or dvd) */
485 static int blkvsc_do_inquiry(struct block_device_context *blkdev)
487 struct blkvsc_request *blkvsc_req;
488 struct page *page_buf;
489 unsigned char *buf;
490 unsigned char device_type;
492 DPRINT_DBG(BLKVSC_DRV, "blkvsc_do_inquiry()\n");
494 blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_KERNEL);
495 if (!blkvsc_req)
496 return -ENOMEM;
498 memset(blkvsc_req, 0, sizeof(struct blkvsc_request));
499 page_buf = alloc_page(GFP_KERNEL);
500 if (!page_buf) {
501 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
502 return -ENOMEM;
505 init_waitqueue_head(&blkvsc_req->wevent);
506 blkvsc_req->dev = blkdev;
507 blkvsc_req->req = NULL;
508 blkvsc_req->write = 0;
510 blkvsc_req->request.data_buffer.pfn_array[0] = page_to_pfn(page_buf);
511 blkvsc_req->request.data_buffer.offset = 0;
512 blkvsc_req->request.data_buffer.len = 64;
514 blkvsc_req->cmnd[0] = INQUIRY;
515 blkvsc_req->cmnd[1] = 0x1; /* Get product data */
516 blkvsc_req->cmnd[2] = 0x83; /* mode page 83 */
517 blkvsc_req->cmnd[4] = 64;
518 blkvsc_req->cmd_len = 6;
521 * Set this here since the completion routine may be invoked and
522 * completed before we return
524 blkvsc_req->cond = 0;
526 blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
528 DPRINT_DBG(BLKVSC_DRV, "waiting %p to complete - cond %d\n",
529 blkvsc_req, blkvsc_req->cond);
531 wait_event_interruptible(blkvsc_req->wevent, blkvsc_req->cond);
533 buf = kmap(page_buf);
535 /* print_hex_dump_bytes("", DUMP_PREFIX_NONE, buf, 64); */
536 /* be to le */
537 device_type = buf[0] & 0x1F;
539 if (device_type == 0x0) {
540 blkdev->device_type = HARDDISK_TYPE;
541 } else if (device_type == 0x5) {
542 blkdev->device_type = DVD_TYPE;
543 } else {
544 /* TODO: this is currently unsupported device type */
545 blkdev->device_type = UNKNOWN_DEV_TYPE;
548 DPRINT_DBG(BLKVSC_DRV, "device type %d\n", device_type);
550 blkdev->device_id_len = buf[7];
551 if (blkdev->device_id_len > 64)
552 blkdev->device_id_len = 64;
554 memcpy(blkdev->device_id, &buf[8], blkdev->device_id_len);
555 /* printk_hex_dump_bytes("", DUMP_PREFIX_NONE, blkdev->device_id,
556 * blkdev->device_id_len); */
558 kunmap(page_buf);
560 __free_page(page_buf);
562 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
564 return 0;
567 /* Do a scsi READ_CAPACITY cmd here to get the size of the disk */
568 static int blkvsc_do_read_capacity(struct block_device_context *blkdev)
570 struct blkvsc_request *blkvsc_req;
571 struct page *page_buf;
572 unsigned char *buf;
573 struct scsi_sense_hdr sense_hdr;
575 DPRINT_DBG(BLKVSC_DRV, "blkvsc_do_read_capacity()\n");
577 blkdev->sector_size = 0;
578 blkdev->capacity = 0;
579 blkdev->media_not_present = 0; /* assume a disk is present */
581 blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_KERNEL);
582 if (!blkvsc_req)
583 return -ENOMEM;
585 memset(blkvsc_req, 0, sizeof(struct blkvsc_request));
586 page_buf = alloc_page(GFP_KERNEL);
587 if (!page_buf) {
588 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
589 return -ENOMEM;
592 init_waitqueue_head(&blkvsc_req->wevent);
593 blkvsc_req->dev = blkdev;
594 blkvsc_req->req = NULL;
595 blkvsc_req->write = 0;
597 blkvsc_req->request.data_buffer.pfn_array[0] = page_to_pfn(page_buf);
598 blkvsc_req->request.data_buffer.offset = 0;
599 blkvsc_req->request.data_buffer.len = 8;
601 blkvsc_req->cmnd[0] = READ_CAPACITY;
602 blkvsc_req->cmd_len = 16;
605 * Set this here since the completion routine may be invoked
606 * and completed before we return
608 blkvsc_req->cond = 0;
610 blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
612 DPRINT_DBG(BLKVSC_DRV, "waiting %p to complete - cond %d\n",
613 blkvsc_req, blkvsc_req->cond);
615 wait_event_interruptible(blkvsc_req->wevent, blkvsc_req->cond);
617 /* check error */
618 if (blkvsc_req->request.status) {
619 scsi_normalize_sense(blkvsc_req->sense_buffer,
620 SCSI_SENSE_BUFFERSIZE, &sense_hdr);
622 if (sense_hdr.asc == 0x3A) {
623 /* Medium not present */
624 blkdev->media_not_present = 1;
626 return 0;
628 buf = kmap(page_buf);
630 /* be to le */
631 blkdev->capacity = ((buf[0] << 24) | (buf[1] << 16) |
632 (buf[2] << 8) | buf[3]) + 1;
633 blkdev->sector_size = (buf[4] << 24) | (buf[5] << 16) |
634 (buf[6] << 8) | buf[7];
636 kunmap(page_buf);
638 __free_page(page_buf);
640 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
642 return 0;
645 static int blkvsc_do_read_capacity16(struct block_device_context *blkdev)
647 struct blkvsc_request *blkvsc_req;
648 struct page *page_buf;
649 unsigned char *buf;
650 struct scsi_sense_hdr sense_hdr;
652 DPRINT_DBG(BLKVSC_DRV, "blkvsc_do_read_capacity16()\n");
654 blkdev->sector_size = 0;
655 blkdev->capacity = 0;
656 blkdev->media_not_present = 0; /* assume a disk is present */
658 blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_KERNEL);
659 if (!blkvsc_req)
660 return -ENOMEM;
662 memset(blkvsc_req, 0, sizeof(struct blkvsc_request));
663 page_buf = alloc_page(GFP_KERNEL);
664 if (!page_buf) {
665 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
666 return -ENOMEM;
669 init_waitqueue_head(&blkvsc_req->wevent);
670 blkvsc_req->dev = blkdev;
671 blkvsc_req->req = NULL;
672 blkvsc_req->write = 0;
674 blkvsc_req->request.data_buffer.pfn_array[0] = page_to_pfn(page_buf);
675 blkvsc_req->request.data_buffer.offset = 0;
676 blkvsc_req->request.data_buffer.len = 12;
678 blkvsc_req->cmnd[0] = 0x9E; /* READ_CAPACITY16; */
679 blkvsc_req->cmd_len = 16;
682 * Set this here since the completion routine may be invoked
683 * and completed before we return
685 blkvsc_req->cond = 0;
687 blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
689 DPRINT_DBG(BLKVSC_DRV, "waiting %p to complete - cond %d\n",
690 blkvsc_req, blkvsc_req->cond);
692 wait_event_interruptible(blkvsc_req->wevent, blkvsc_req->cond);
694 /* check error */
695 if (blkvsc_req->request.status) {
696 scsi_normalize_sense(blkvsc_req->sense_buffer,
697 SCSI_SENSE_BUFFERSIZE, &sense_hdr);
698 if (sense_hdr.asc == 0x3A) {
699 /* Medium not present */
700 blkdev->media_not_present = 1;
702 return 0;
704 buf = kmap(page_buf);
706 /* be to le */
707 blkdev->capacity = be64_to_cpu(*(unsigned long long *) &buf[0]) + 1;
708 blkdev->sector_size = be32_to_cpu(*(unsigned int *)&buf[8]);
710 #if 0
711 blkdev->capacity = ((buf[0] << 24) | (buf[1] << 16) |
712 (buf[2] << 8) | buf[3]) + 1;
713 blkdev->sector_size = (buf[4] << 24) | (buf[5] << 16) |
714 (buf[6] << 8) | buf[7];
715 #endif
717 kunmap(page_buf);
719 __free_page(page_buf);
721 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
723 return 0;
727 * blkvsc_remove() - Callback when our device is removed
729 static int blkvsc_remove(struct device *device)
731 struct driver_context *driver_ctx =
732 driver_to_driver_context(device->driver);
733 struct blkvsc_driver_context *blkvsc_drv_ctx =
734 (struct blkvsc_driver_context *)driver_ctx;
735 struct storvsc_driver_object *storvsc_drv_obj =
736 &blkvsc_drv_ctx->drv_obj;
737 struct vm_device *device_ctx = device_to_vm_device(device);
738 struct hv_device *device_obj = &device_ctx->device_obj;
739 struct block_device_context *blkdev = dev_get_drvdata(device);
740 unsigned long flags;
741 int ret;
743 DPRINT_DBG(BLKVSC_DRV, "blkvsc_remove()\n");
745 if (!storvsc_drv_obj->base.dev_rm)
746 return -1;
749 * Call to the vsc driver to let it know that the device is being
750 * removed
752 ret = storvsc_drv_obj->base.dev_rm(device_obj);
753 if (ret != 0) {
754 /* TODO: */
755 DPRINT_ERR(BLKVSC_DRV,
756 "unable to remove blkvsc device (ret %d)", ret);
759 /* Get to a known state */
760 spin_lock_irqsave(&blkdev->lock, flags);
762 blkdev->shutting_down = 1;
764 blk_stop_queue(blkdev->gd->queue);
766 spin_unlock_irqrestore(&blkdev->lock, flags);
768 while (blkdev->num_outstanding_reqs) {
769 DPRINT_INFO(STORVSC, "waiting for %d requests to complete...",
770 blkdev->num_outstanding_reqs);
771 udelay(100);
774 blkvsc_do_flush(blkdev);
776 spin_lock_irqsave(&blkdev->lock, flags);
778 blkvsc_cancel_pending_reqs(blkdev);
780 spin_unlock_irqrestore(&blkdev->lock, flags);
782 blk_cleanup_queue(blkdev->gd->queue);
784 del_gendisk(blkdev->gd);
786 kmem_cache_destroy(blkdev->request_pool);
788 kfree(blkdev);
790 return ret;
793 static void blkvsc_init_rw(struct blkvsc_request *blkvsc_req)
795 /* ASSERT(blkvsc_req->req); */
796 /* ASSERT(blkvsc_req->sector_count <= (MAX_MULTIPAGE_BUFFER_COUNT*8)); */
798 blkvsc_req->cmd_len = 16;
800 if (blkvsc_req->sector_start > 0xffffffff) {
801 if (rq_data_dir(blkvsc_req->req)) {
802 blkvsc_req->write = 1;
803 blkvsc_req->cmnd[0] = WRITE_16;
804 } else {
805 blkvsc_req->write = 0;
806 blkvsc_req->cmnd[0] = READ_16;
809 blkvsc_req->cmnd[1] |=
810 (blkvsc_req->req->cmd_flags & REQ_FUA) ? 0x8 : 0;
812 *(unsigned long long *)&blkvsc_req->cmnd[2] =
813 cpu_to_be64(blkvsc_req->sector_start);
814 *(unsigned int *)&blkvsc_req->cmnd[10] =
815 cpu_to_be32(blkvsc_req->sector_count);
816 } else if ((blkvsc_req->sector_count > 0xff) ||
817 (blkvsc_req->sector_start > 0x1fffff)) {
818 if (rq_data_dir(blkvsc_req->req)) {
819 blkvsc_req->write = 1;
820 blkvsc_req->cmnd[0] = WRITE_10;
821 } else {
822 blkvsc_req->write = 0;
823 blkvsc_req->cmnd[0] = READ_10;
826 blkvsc_req->cmnd[1] |=
827 (blkvsc_req->req->cmd_flags & REQ_FUA) ? 0x8 : 0;
829 *(unsigned int *)&blkvsc_req->cmnd[2] =
830 cpu_to_be32(blkvsc_req->sector_start);
831 *(unsigned short *)&blkvsc_req->cmnd[7] =
832 cpu_to_be16(blkvsc_req->sector_count);
833 } else {
834 if (rq_data_dir(blkvsc_req->req)) {
835 blkvsc_req->write = 1;
836 blkvsc_req->cmnd[0] = WRITE_6;
837 } else {
838 blkvsc_req->write = 0;
839 blkvsc_req->cmnd[0] = READ_6;
842 *(unsigned int *)&blkvsc_req->cmnd[1] =
843 cpu_to_be32(blkvsc_req->sector_start) >> 8;
844 blkvsc_req->cmnd[1] &= 0x1f;
845 blkvsc_req->cmnd[4] = (unsigned char)blkvsc_req->sector_count;
849 static int blkvsc_submit_request(struct blkvsc_request *blkvsc_req,
850 void (*request_completion)(struct hv_storvsc_request *))
852 struct block_device_context *blkdev = blkvsc_req->dev;
853 struct vm_device *device_ctx = blkdev->device_ctx;
854 struct driver_context *driver_ctx =
855 driver_to_driver_context(device_ctx->device.driver);
856 struct blkvsc_driver_context *blkvsc_drv_ctx =
857 (struct blkvsc_driver_context *)driver_ctx;
858 struct storvsc_driver_object *storvsc_drv_obj =
859 &blkvsc_drv_ctx->drv_obj;
860 struct hv_storvsc_request *storvsc_req;
861 int ret;
863 DPRINT_DBG(BLKVSC_DRV, "blkvsc_submit_request() - "
864 "req %p type %s start_sector %lu count %ld offset %d "
865 "len %d\n", blkvsc_req,
866 (blkvsc_req->write) ? "WRITE" : "READ",
867 (unsigned long) blkvsc_req->sector_start,
868 blkvsc_req->sector_count,
869 blkvsc_req->request.data_buffer.offset,
870 blkvsc_req->request.data_buffer.len);
871 #if 0
872 for (i = 0; i < (blkvsc_req->request.data_buffer.len >> 12); i++) {
873 DPRINT_DBG(BLKVSC_DRV, "blkvsc_submit_request() - "
874 "req %p pfn[%d] %llx\n",
875 blkvsc_req, i,
876 blkvsc_req->request.data_buffer.pfn_array[i]);
878 #endif
880 storvsc_req = &blkvsc_req->request;
881 storvsc_req->extension = (void *)((unsigned long)blkvsc_req +
882 sizeof(struct blkvsc_request));
884 storvsc_req->type = blkvsc_req->write ? WRITE_TYPE : READ_TYPE;
886 storvsc_req->on_io_completion = request_completion;
887 storvsc_req->context = blkvsc_req;
889 storvsc_req->host = blkdev->port;
890 storvsc_req->bus = blkdev->path;
891 storvsc_req->target_id = blkdev->target;
892 storvsc_req->lun_id = 0; /* this is not really used at all */
894 storvsc_req->cdb_len = blkvsc_req->cmd_len;
895 storvsc_req->cdb = blkvsc_req->cmnd;
897 storvsc_req->sense_buffer = blkvsc_req->sense_buffer;
898 storvsc_req->sense_buffer_size = SCSI_SENSE_BUFFERSIZE;
900 ret = storvsc_drv_obj->on_io_request(&blkdev->device_ctx->device_obj,
901 &blkvsc_req->request);
902 if (ret == 0)
903 blkdev->num_outstanding_reqs++;
905 return ret;
909 * We break the request into 1 or more blkvsc_requests and submit
910 * them. If we cant submit them all, we put them on the
911 * pending_list. The blkvsc_request() will work on the pending_list.
913 static int blkvsc_do_request(struct block_device_context *blkdev,
914 struct request *req)
916 struct bio *bio = NULL;
917 struct bio_vec *bvec = NULL;
918 struct bio_vec *prev_bvec = NULL;
919 struct blkvsc_request *blkvsc_req = NULL;
920 struct blkvsc_request *tmp;
921 int databuf_idx = 0;
922 int seg_idx = 0;
923 sector_t start_sector;
924 unsigned long num_sectors = 0;
925 int ret = 0;
926 int pending = 0;
927 struct blkvsc_request_group *group = NULL;
929 DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p sect %lu\n", blkdev, req,
930 (unsigned long)blk_rq_pos(req));
932 /* Create a group to tie req to list of blkvsc_reqs */
933 group = kmem_cache_alloc(blkdev->request_pool, GFP_ATOMIC);
934 if (!group)
935 return -ENOMEM;
937 INIT_LIST_HEAD(&group->blkvsc_req_list);
938 group->outstanding = group->status = 0;
940 start_sector = blk_rq_pos(req);
942 /* foreach bio in the request */
943 if (req->bio) {
944 for (bio = req->bio; bio; bio = bio->bi_next) {
946 * Map this bio into an existing or new storvsc request
948 bio_for_each_segment(bvec, bio, seg_idx) {
949 DPRINT_DBG(BLKVSC_DRV, "bio_for_each_segment() "
950 "- req %p bio %p bvec %p seg_idx %d "
951 "databuf_idx %d\n", req, bio, bvec,
952 seg_idx, databuf_idx);
954 /* Get a new storvsc request */
955 /* 1st-time */
956 if ((!blkvsc_req) ||
957 (databuf_idx >= MAX_MULTIPAGE_BUFFER_COUNT)
958 /* hole at the begin of page */
959 || (bvec->bv_offset != 0) ||
960 /* hold at the end of page */
961 (prev_bvec &&
962 (prev_bvec->bv_len != PAGE_SIZE))) {
963 /* submit the prev one */
964 if (blkvsc_req) {
965 blkvsc_req->sector_start = start_sector;
966 sector_div(blkvsc_req->sector_start, (blkdev->sector_size >> 9));
968 blkvsc_req->sector_count = num_sectors / (blkdev->sector_size >> 9);
969 blkvsc_init_rw(blkvsc_req);
973 * Create new blkvsc_req to represent
974 * the current bvec
976 blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_ATOMIC);
977 if (!blkvsc_req) {
978 /* free up everything */
979 list_for_each_entry_safe(
980 blkvsc_req, tmp,
981 &group->blkvsc_req_list,
982 req_entry) {
983 list_del(&blkvsc_req->req_entry);
984 kmem_cache_free(blkdev->request_pool, blkvsc_req);
987 kmem_cache_free(blkdev->request_pool, group);
988 return -ENOMEM;
991 memset(blkvsc_req, 0,
992 sizeof(struct blkvsc_request));
994 blkvsc_req->dev = blkdev;
995 blkvsc_req->req = req;
996 blkvsc_req->request.data_buffer.offset
997 = bvec->bv_offset;
998 blkvsc_req->request.data_buffer.len
999 = 0;
1001 /* Add to the group */
1002 blkvsc_req->group = group;
1003 blkvsc_req->group->outstanding++;
1004 list_add_tail(&blkvsc_req->req_entry,
1005 &blkvsc_req->group->blkvsc_req_list);
1007 start_sector += num_sectors;
1008 num_sectors = 0;
1009 databuf_idx = 0;
1012 /* Add the curr bvec/segment to the curr blkvsc_req */
1013 blkvsc_req->request.data_buffer.
1014 pfn_array[databuf_idx]
1015 = page_to_pfn(bvec->bv_page);
1016 blkvsc_req->request.data_buffer.len
1017 += bvec->bv_len;
1019 prev_bvec = bvec;
1021 databuf_idx++;
1022 num_sectors += bvec->bv_len >> 9;
1024 } /* bio_for_each_segment */
1026 } /* rq_for_each_bio */
1029 /* Handle the last one */
1030 if (blkvsc_req) {
1031 DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p group %p count %d\n",
1032 blkdev, req, blkvsc_req->group,
1033 blkvsc_req->group->outstanding);
1035 blkvsc_req->sector_start = start_sector;
1036 sector_div(blkvsc_req->sector_start,
1037 (blkdev->sector_size >> 9));
1039 blkvsc_req->sector_count = num_sectors /
1040 (blkdev->sector_size >> 9);
1042 blkvsc_init_rw(blkvsc_req);
1045 list_for_each_entry(blkvsc_req, &group->blkvsc_req_list, req_entry) {
1046 if (pending) {
1047 DPRINT_DBG(BLKVSC_DRV, "adding blkvsc_req to "
1048 "pending_list - blkvsc_req %p start_sect %lu"
1049 " sect_count %ld (%lu %ld)\n", blkvsc_req,
1050 (unsigned long)blkvsc_req->sector_start,
1051 blkvsc_req->sector_count,
1052 (unsigned long)start_sector,
1053 (unsigned long)num_sectors);
1055 list_add_tail(&blkvsc_req->pend_entry,
1056 &blkdev->pending_list);
1057 } else {
1058 ret = blkvsc_submit_request(blkvsc_req,
1059 blkvsc_request_completion);
1060 if (ret == -1) {
1061 pending = 1;
1062 list_add_tail(&blkvsc_req->pend_entry,
1063 &blkdev->pending_list);
1066 DPRINT_DBG(BLKVSC_DRV, "submitted blkvsc_req %p "
1067 "start_sect %lu sect_count %ld (%lu %ld) "
1068 "ret %d\n", blkvsc_req,
1069 (unsigned long)blkvsc_req->sector_start,
1070 blkvsc_req->sector_count,
1071 (unsigned long)start_sector,
1072 num_sectors, ret);
1076 return pending;
1079 static void blkvsc_cmd_completion(struct hv_storvsc_request *request)
1081 struct blkvsc_request *blkvsc_req =
1082 (struct blkvsc_request *)request->context;
1083 struct block_device_context *blkdev =
1084 (struct block_device_context *)blkvsc_req->dev;
1085 struct scsi_sense_hdr sense_hdr;
1087 DPRINT_DBG(BLKVSC_DRV, "blkvsc_cmd_completion() - req %p\n",
1088 blkvsc_req);
1090 blkdev->num_outstanding_reqs--;
1092 if (blkvsc_req->request.status)
1093 if (scsi_normalize_sense(blkvsc_req->sense_buffer,
1094 SCSI_SENSE_BUFFERSIZE, &sense_hdr))
1095 scsi_print_sense_hdr("blkvsc", &sense_hdr);
1097 blkvsc_req->cond = 1;
1098 wake_up_interruptible(&blkvsc_req->wevent);
1101 static void blkvsc_request_completion(struct hv_storvsc_request *request)
1103 struct blkvsc_request *blkvsc_req =
1104 (struct blkvsc_request *)request->context;
1105 struct block_device_context *blkdev =
1106 (struct block_device_context *)blkvsc_req->dev;
1107 unsigned long flags;
1108 struct blkvsc_request *comp_req, *tmp;
1110 /* ASSERT(blkvsc_req->group); */
1112 DPRINT_DBG(BLKVSC_DRV, "blkdev %p blkvsc_req %p group %p type %s "
1113 "sect_start %lu sect_count %ld len %d group outstd %d "
1114 "total outstd %d\n",
1115 blkdev, blkvsc_req, blkvsc_req->group,
1116 (blkvsc_req->write) ? "WRITE" : "READ",
1117 (unsigned long)blkvsc_req->sector_start,
1118 blkvsc_req->sector_count,
1119 blkvsc_req->request.data_buffer.len,
1120 blkvsc_req->group->outstanding,
1121 blkdev->num_outstanding_reqs);
1123 spin_lock_irqsave(&blkdev->lock, flags);
1125 blkdev->num_outstanding_reqs--;
1126 blkvsc_req->group->outstanding--;
1129 * Only start processing when all the blkvsc_reqs are
1130 * completed. This guarantees no out-of-order blkvsc_req
1131 * completion when calling end_that_request_first()
1133 if (blkvsc_req->group->outstanding == 0) {
1134 list_for_each_entry_safe(comp_req, tmp,
1135 &blkvsc_req->group->blkvsc_req_list,
1136 req_entry) {
1137 DPRINT_DBG(BLKVSC_DRV, "completing blkvsc_req %p "
1138 "sect_start %lu sect_count %ld\n",
1139 comp_req,
1140 (unsigned long)comp_req->sector_start,
1141 comp_req->sector_count);
1143 list_del(&comp_req->req_entry);
1145 if (!__blk_end_request(comp_req->req,
1146 (!comp_req->request.status ? 0 : -EIO),
1147 comp_req->sector_count * blkdev->sector_size)) {
1149 * All the sectors have been xferred ie the
1150 * request is done
1152 DPRINT_DBG(BLKVSC_DRV, "req %p COMPLETED\n",
1153 comp_req->req);
1154 kmem_cache_free(blkdev->request_pool,
1155 comp_req->group);
1158 kmem_cache_free(blkdev->request_pool, comp_req);
1161 if (!blkdev->shutting_down) {
1162 blkvsc_do_pending_reqs(blkdev);
1163 blk_start_queue(blkdev->gd->queue);
1164 blkvsc_request(blkdev->gd->queue);
1168 spin_unlock_irqrestore(&blkdev->lock, flags);
1171 static int blkvsc_cancel_pending_reqs(struct block_device_context *blkdev)
1173 struct blkvsc_request *pend_req, *tmp;
1174 struct blkvsc_request *comp_req, *tmp2;
1176 int ret = 0;
1178 DPRINT_DBG(BLKVSC_DRV, "blkvsc_cancel_pending_reqs()");
1180 /* Flush the pending list first */
1181 list_for_each_entry_safe(pend_req, tmp, &blkdev->pending_list,
1182 pend_entry) {
1184 * The pend_req could be part of a partially completed
1185 * request. If so, complete those req first until we
1186 * hit the pend_req
1188 list_for_each_entry_safe(comp_req, tmp2,
1189 &pend_req->group->blkvsc_req_list,
1190 req_entry) {
1191 DPRINT_DBG(BLKVSC_DRV, "completing blkvsc_req %p "
1192 "sect_start %lu sect_count %ld\n",
1193 comp_req,
1194 (unsigned long) comp_req->sector_start,
1195 comp_req->sector_count);
1197 if (comp_req == pend_req)
1198 break;
1200 list_del(&comp_req->req_entry);
1202 if (comp_req->req) {
1203 ret = __blk_end_request(comp_req->req,
1204 (!comp_req->request.status ? 0 : -EIO),
1205 comp_req->sector_count *
1206 blkdev->sector_size);
1208 /* FIXME: shouldn't this do more than return? */
1209 if (ret)
1210 goto out;
1213 kmem_cache_free(blkdev->request_pool, comp_req);
1216 DPRINT_DBG(BLKVSC_DRV, "cancelling pending request - %p\n",
1217 pend_req);
1219 list_del(&pend_req->pend_entry);
1221 list_del(&pend_req->req_entry);
1223 if (comp_req->req) {
1224 if (!__blk_end_request(pend_req->req, -EIO,
1225 pend_req->sector_count *
1226 blkdev->sector_size)) {
1228 * All the sectors have been xferred ie the
1229 * request is done
1231 DPRINT_DBG(BLKVSC_DRV,
1232 "blkvsc_cancel_pending_reqs() - "
1233 "req %p COMPLETED\n", pend_req->req);
1234 kmem_cache_free(blkdev->request_pool,
1235 pend_req->group);
1239 kmem_cache_free(blkdev->request_pool, pend_req);
1242 out:
1243 return ret;
1246 static int blkvsc_do_pending_reqs(struct block_device_context *blkdev)
1248 struct blkvsc_request *pend_req, *tmp;
1249 int ret = 0;
1251 /* Flush the pending list first */
1252 list_for_each_entry_safe(pend_req, tmp, &blkdev->pending_list,
1253 pend_entry) {
1254 DPRINT_DBG(BLKVSC_DRV, "working off pending_list - %p\n",
1255 pend_req);
1257 ret = blkvsc_submit_request(pend_req,
1258 blkvsc_request_completion);
1259 if (ret != 0)
1260 break;
1261 else
1262 list_del(&pend_req->pend_entry);
1265 return ret;
1268 static void blkvsc_request(struct request_queue *queue)
1270 struct block_device_context *blkdev = NULL;
1271 struct request *req;
1272 int ret = 0;
1274 DPRINT_DBG(BLKVSC_DRV, "- enter\n");
1275 while ((req = blk_peek_request(queue)) != NULL) {
1276 DPRINT_DBG(BLKVSC_DRV, "- req %p\n", req);
1278 blkdev = req->rq_disk->private_data;
1279 if (blkdev->shutting_down || req->cmd_type != REQ_TYPE_FS ||
1280 blkdev->media_not_present) {
1281 __blk_end_request_cur(req, 0);
1282 continue;
1285 ret = blkvsc_do_pending_reqs(blkdev);
1287 if (ret != 0) {
1288 DPRINT_DBG(BLKVSC_DRV,
1289 "- stop queue - pending_list not empty\n");
1290 blk_stop_queue(queue);
1291 break;
1294 blk_start_request(req);
1296 ret = blkvsc_do_request(blkdev, req);
1297 if (ret > 0) {
1298 DPRINT_DBG(BLKVSC_DRV, "- stop queue - no room\n");
1299 blk_stop_queue(queue);
1300 break;
1301 } else if (ret < 0) {
1302 DPRINT_DBG(BLKVSC_DRV, "- stop queue - no mem\n");
1303 blk_requeue_request(queue, req);
1304 blk_stop_queue(queue);
1305 break;
1310 static int blkvsc_open(struct block_device *bdev, fmode_t mode)
1312 struct block_device_context *blkdev = bdev->bd_disk->private_data;
1314 DPRINT_DBG(BLKVSC_DRV, "- users %d disk %s\n", blkdev->users,
1315 blkdev->gd->disk_name);
1317 mutex_lock(&blkvsc_mutex);
1318 spin_lock(&blkdev->lock);
1320 if (!blkdev->users && blkdev->device_type == DVD_TYPE) {
1321 spin_unlock(&blkdev->lock);
1322 check_disk_change(bdev);
1323 spin_lock(&blkdev->lock);
1326 blkdev->users++;
1328 spin_unlock(&blkdev->lock);
1329 mutex_unlock(&blkvsc_mutex);
1330 return 0;
1333 static int blkvsc_release(struct gendisk *disk, fmode_t mode)
1335 struct block_device_context *blkdev = disk->private_data;
1337 DPRINT_DBG(BLKVSC_DRV, "- users %d disk %s\n", blkdev->users,
1338 blkdev->gd->disk_name);
1340 mutex_lock(&blkvsc_mutex);
1341 spin_lock(&blkdev->lock);
1342 if (blkdev->users == 1) {
1343 spin_unlock(&blkdev->lock);
1344 blkvsc_do_flush(blkdev);
1345 spin_lock(&blkdev->lock);
1348 blkdev->users--;
1350 spin_unlock(&blkdev->lock);
1351 mutex_unlock(&blkvsc_mutex);
1352 return 0;
1355 static int blkvsc_media_changed(struct gendisk *gd)
1357 DPRINT_DBG(BLKVSC_DRV, "- enter\n");
1358 return 1;
1361 static int blkvsc_revalidate_disk(struct gendisk *gd)
1363 struct block_device_context *blkdev = gd->private_data;
1365 DPRINT_DBG(BLKVSC_DRV, "- enter\n");
1367 if (blkdev->device_type == DVD_TYPE) {
1368 blkvsc_do_read_capacity(blkdev);
1369 set_capacity(blkdev->gd, blkdev->capacity *
1370 (blkdev->sector_size/512));
1371 blk_queue_logical_block_size(gd->queue, blkdev->sector_size);
1373 return 0;
1376 static int blkvsc_getgeo(struct block_device *bd, struct hd_geometry *hg)
1378 sector_t total_sectors = get_capacity(bd->bd_disk);
1379 sector_t cylinder_times_heads = 0;
1380 sector_t temp = 0;
1382 int sectors_per_track = 0;
1383 int heads = 0;
1384 int cylinders = 0;
1385 int rem = 0;
1387 if (total_sectors > (65535 * 16 * 255))
1388 total_sectors = (65535 * 16 * 255);
1390 if (total_sectors >= (65535 * 16 * 63)) {
1391 sectors_per_track = 255;
1392 heads = 16;
1394 cylinder_times_heads = total_sectors;
1395 /* sector_div stores the quotient in cylinder_times_heads */
1396 rem = sector_div(cylinder_times_heads, sectors_per_track);
1397 } else {
1398 sectors_per_track = 17;
1400 cylinder_times_heads = total_sectors;
1401 /* sector_div stores the quotient in cylinder_times_heads */
1402 rem = sector_div(cylinder_times_heads, sectors_per_track);
1404 temp = cylinder_times_heads + 1023;
1405 /* sector_div stores the quotient in temp */
1406 rem = sector_div(temp, 1024);
1408 heads = temp;
1410 if (heads < 4)
1411 heads = 4;
1414 if (cylinder_times_heads >= (heads * 1024) || (heads > 16)) {
1415 sectors_per_track = 31;
1416 heads = 16;
1418 cylinder_times_heads = total_sectors;
1420 * sector_div stores the quotient in
1421 * cylinder_times_heads
1423 rem = sector_div(cylinder_times_heads,
1424 sectors_per_track);
1427 if (cylinder_times_heads >= (heads * 1024)) {
1428 sectors_per_track = 63;
1429 heads = 16;
1431 cylinder_times_heads = total_sectors;
1433 * sector_div stores the quotient in
1434 * cylinder_times_heads
1436 rem = sector_div(cylinder_times_heads,
1437 sectors_per_track);
1441 temp = cylinder_times_heads;
1442 /* sector_div stores the quotient in temp */
1443 rem = sector_div(temp, heads);
1444 cylinders = temp;
1446 hg->heads = heads;
1447 hg->sectors = sectors_per_track;
1448 hg->cylinders = cylinders;
1450 DPRINT_INFO(BLKVSC_DRV, "CHS (%d, %d, %d)", cylinders, heads,
1451 sectors_per_track);
1453 return 0;
1456 static int blkvsc_ioctl(struct block_device *bd, fmode_t mode,
1457 unsigned cmd, unsigned long argument)
1459 /* struct block_device_context *blkdev = bd->bd_disk->private_data; */
1460 int ret;
1462 switch (cmd) {
1464 * TODO: I think there is certain format for HDIO_GET_IDENTITY rather
1465 * than just a GUID. Commented it out for now.
1467 #if 0
1468 case HDIO_GET_IDENTITY:
1469 DPRINT_INFO(BLKVSC_DRV, "HDIO_GET_IDENTITY\n");
1470 if (copy_to_user((void __user *)arg, blkdev->device_id,
1471 blkdev->device_id_len))
1472 ret = -EFAULT;
1473 break;
1474 #endif
1475 default:
1476 ret = -EINVAL;
1477 break;
1480 return ret;
1483 static int __init blkvsc_init(void)
1485 int ret;
1487 BUILD_BUG_ON(sizeof(sector_t) != 8);
1489 DPRINT_INFO(BLKVSC_DRV, "Blkvsc initializing....");
1491 ret = blkvsc_drv_init(blk_vsc_initialize);
1493 return ret;
1496 static void __exit blkvsc_exit(void)
1498 blkvsc_drv_exit();
1501 MODULE_LICENSE("GPL");
1502 MODULE_VERSION(HV_DRV_VERSION);
1503 MODULE_DESCRIPTION("Microsoft Hyper-V virtual block driver");
1504 module_init(blkvsc_init);
1505 module_exit(blkvsc_exit);