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Commit | Line | Data |
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9f27ee59 JF |
1 | /* |
2 | * blkfront.c | |
3 | * | |
4 | * XenLinux virtual block device driver. | |
5 | * | |
6 | * Copyright (c) 2003-2004, Keir Fraser & Steve Hand | |
7 | * Modifications by Mark A. Williamson are (c) Intel Research Cambridge | |
8 | * Copyright (c) 2004, Christian Limpach | |
9 | * Copyright (c) 2004, Andrew Warfield | |
10 | * Copyright (c) 2005, Christopher Clark | |
11 | * Copyright (c) 2005, XenSource Ltd | |
12 | * | |
13 | * This program is free software; you can redistribute it and/or | |
14 | * modify it under the terms of the GNU General Public License version 2 | |
15 | * as published by the Free Software Foundation; or, when distributed | |
16 | * separately from the Linux kernel or incorporated into other | |
17 | * software packages, subject to the following license: | |
18 | * | |
19 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
20 | * of this source file (the "Software"), to deal in the Software without | |
21 | * restriction, including without limitation the rights to use, copy, modify, | |
22 | * merge, publish, distribute, sublicense, and/or sell copies of the Software, | |
23 | * and to permit persons to whom the Software is furnished to do so, subject to | |
24 | * the following conditions: | |
25 | * | |
26 | * The above copyright notice and this permission notice shall be included in | |
27 | * all copies or substantial portions of the Software. | |
28 | * | |
29 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
30 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
31 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
32 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
33 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
34 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS | |
35 | * IN THE SOFTWARE. | |
36 | */ | |
37 | ||
38 | #include <linux/interrupt.h> | |
39 | #include <linux/blkdev.h> | |
597592d9 | 40 | #include <linux/hdreg.h> |
440a01a7 | 41 | #include <linux/cdrom.h> |
9f27ee59 | 42 | #include <linux/module.h> |
5a0e3ad6 | 43 | #include <linux/slab.h> |
2a48fc0a | 44 | #include <linux/mutex.h> |
9e973e64 | 45 | #include <linux/scatterlist.h> |
34ae2e47 | 46 | #include <linux/bitmap.h> |
9f27ee59 | 47 | |
1ccbf534 | 48 | #include <xen/xen.h> |
9f27ee59 JF |
49 | #include <xen/xenbus.h> |
50 | #include <xen/grant_table.h> | |
51 | #include <xen/events.h> | |
52 | #include <xen/page.h> | |
c1c5413a | 53 | #include <xen/platform_pci.h> |
9f27ee59 JF |
54 | |
55 | #include <xen/interface/grant_table.h> | |
56 | #include <xen/interface/io/blkif.h> | |
3e334239 | 57 | #include <xen/interface/io/protocols.h> |
9f27ee59 JF |
58 | |
59 | #include <asm/xen/hypervisor.h> | |
60 | ||
61 | enum blkif_state { | |
62 | BLKIF_STATE_DISCONNECTED, | |
63 | BLKIF_STATE_CONNECTED, | |
64 | BLKIF_STATE_SUSPENDED, | |
65 | }; | |
66 | ||
67 | struct blk_shadow { | |
68 | struct blkif_request req; | |
a945b980 | 69 | struct request *request; |
9f27ee59 JF |
70 | unsigned long frame[BLKIF_MAX_SEGMENTS_PER_REQUEST]; |
71 | }; | |
72 | ||
2a48fc0a | 73 | static DEFINE_MUTEX(blkfront_mutex); |
83d5cde4 | 74 | static const struct block_device_operations xlvbd_block_fops; |
9f27ee59 | 75 | |
667c78af | 76 | #define BLK_RING_SIZE __CONST_RING_SIZE(blkif, PAGE_SIZE) |
9f27ee59 JF |
77 | |
78 | /* | |
79 | * We have one of these per vbd, whether ide, scsi or 'other'. They | |
80 | * hang in private_data off the gendisk structure. We may end up | |
81 | * putting all kinds of interesting stuff here :-) | |
82 | */ | |
83 | struct blkfront_info | |
84 | { | |
3467811e | 85 | spinlock_t io_lock; |
b70f5fa0 | 86 | struct mutex mutex; |
9f27ee59 | 87 | struct xenbus_device *xbdev; |
9f27ee59 JF |
88 | struct gendisk *gd; |
89 | int vdevice; | |
90 | blkif_vdev_t handle; | |
91 | enum blkif_state connected; | |
92 | int ring_ref; | |
93 | struct blkif_front_ring ring; | |
9e973e64 | 94 | struct scatterlist sg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; |
9f27ee59 JF |
95 | unsigned int evtchn, irq; |
96 | struct request_queue *rq; | |
97 | struct work_struct work; | |
98 | struct gnttab_free_callback callback; | |
99 | struct blk_shadow shadow[BLK_RING_SIZE]; | |
100 | unsigned long shadow_free; | |
4913efe4 | 101 | unsigned int feature_flush; |
edf6ef59 | 102 | unsigned int flush_op; |
5ea42986 KRW |
103 | unsigned int feature_discard:1; |
104 | unsigned int feature_secdiscard:1; | |
ed30bf31 LD |
105 | unsigned int discard_granularity; |
106 | unsigned int discard_alignment; | |
1d78d705 | 107 | int is_ready; |
9f27ee59 JF |
108 | }; |
109 | ||
0e345826 JB |
110 | static unsigned int nr_minors; |
111 | static unsigned long *minors; | |
112 | static DEFINE_SPINLOCK(minor_lock); | |
113 | ||
9f27ee59 JF |
114 | #define MAXIMUM_OUTSTANDING_BLOCK_REQS \ |
115 | (BLKIF_MAX_SEGMENTS_PER_REQUEST * BLK_RING_SIZE) | |
116 | #define GRANT_INVALID_REF 0 | |
117 | ||
118 | #define PARTS_PER_DISK 16 | |
9246b5f0 | 119 | #define PARTS_PER_EXT_DISK 256 |
9f27ee59 JF |
120 | |
121 | #define BLKIF_MAJOR(dev) ((dev)>>8) | |
122 | #define BLKIF_MINOR(dev) ((dev) & 0xff) | |
123 | ||
9246b5f0 CL |
124 | #define EXT_SHIFT 28 |
125 | #define EXTENDED (1<<EXT_SHIFT) | |
126 | #define VDEV_IS_EXTENDED(dev) ((dev)&(EXTENDED)) | |
127 | #define BLKIF_MINOR_EXT(dev) ((dev)&(~EXTENDED)) | |
c80a4209 SS |
128 | #define EMULATED_HD_DISK_MINOR_OFFSET (0) |
129 | #define EMULATED_HD_DISK_NAME_OFFSET (EMULATED_HD_DISK_MINOR_OFFSET / 256) | |
196cfe2a SB |
130 | #define EMULATED_SD_DISK_MINOR_OFFSET (0) |
131 | #define EMULATED_SD_DISK_NAME_OFFSET (EMULATED_SD_DISK_MINOR_OFFSET / 256) | |
9f27ee59 | 132 | |
9246b5f0 | 133 | #define DEV_NAME "xvd" /* name in /dev */ |
9f27ee59 JF |
134 | |
135 | static int get_id_from_freelist(struct blkfront_info *info) | |
136 | { | |
137 | unsigned long free = info->shadow_free; | |
b9ed7252 | 138 | BUG_ON(free >= BLK_RING_SIZE); |
97e36834 KRW |
139 | info->shadow_free = info->shadow[free].req.u.rw.id; |
140 | info->shadow[free].req.u.rw.id = 0x0fffffee; /* debug */ | |
9f27ee59 JF |
141 | return free; |
142 | } | |
143 | ||
144 | static void add_id_to_freelist(struct blkfront_info *info, | |
145 | unsigned long id) | |
146 | { | |
97e36834 | 147 | info->shadow[id].req.u.rw.id = info->shadow_free; |
a945b980 | 148 | info->shadow[id].request = NULL; |
9f27ee59 JF |
149 | info->shadow_free = id; |
150 | } | |
151 | ||
0e345826 JB |
152 | static int xlbd_reserve_minors(unsigned int minor, unsigned int nr) |
153 | { | |
154 | unsigned int end = minor + nr; | |
155 | int rc; | |
156 | ||
157 | if (end > nr_minors) { | |
158 | unsigned long *bitmap, *old; | |
159 | ||
f094148a | 160 | bitmap = kcalloc(BITS_TO_LONGS(end), sizeof(*bitmap), |
0e345826 JB |
161 | GFP_KERNEL); |
162 | if (bitmap == NULL) | |
163 | return -ENOMEM; | |
164 | ||
165 | spin_lock(&minor_lock); | |
166 | if (end > nr_minors) { | |
167 | old = minors; | |
168 | memcpy(bitmap, minors, | |
169 | BITS_TO_LONGS(nr_minors) * sizeof(*bitmap)); | |
170 | minors = bitmap; | |
171 | nr_minors = BITS_TO_LONGS(end) * BITS_PER_LONG; | |
172 | } else | |
173 | old = bitmap; | |
174 | spin_unlock(&minor_lock); | |
175 | kfree(old); | |
176 | } | |
177 | ||
178 | spin_lock(&minor_lock); | |
179 | if (find_next_bit(minors, end, minor) >= end) { | |
34ae2e47 | 180 | bitmap_set(minors, minor, nr); |
0e345826 JB |
181 | rc = 0; |
182 | } else | |
183 | rc = -EBUSY; | |
184 | spin_unlock(&minor_lock); | |
185 | ||
186 | return rc; | |
187 | } | |
188 | ||
189 | static void xlbd_release_minors(unsigned int minor, unsigned int nr) | |
190 | { | |
191 | unsigned int end = minor + nr; | |
192 | ||
193 | BUG_ON(end > nr_minors); | |
194 | spin_lock(&minor_lock); | |
34ae2e47 | 195 | bitmap_clear(minors, minor, nr); |
0e345826 JB |
196 | spin_unlock(&minor_lock); |
197 | } | |
198 | ||
9f27ee59 JF |
199 | static void blkif_restart_queue_callback(void *arg) |
200 | { | |
201 | struct blkfront_info *info = (struct blkfront_info *)arg; | |
202 | schedule_work(&info->work); | |
203 | } | |
204 | ||
afe42d7d | 205 | static int blkif_getgeo(struct block_device *bd, struct hd_geometry *hg) |
597592d9 IC |
206 | { |
207 | /* We don't have real geometry info, but let's at least return | |
208 | values consistent with the size of the device */ | |
209 | sector_t nsect = get_capacity(bd->bd_disk); | |
210 | sector_t cylinders = nsect; | |
211 | ||
212 | hg->heads = 0xff; | |
213 | hg->sectors = 0x3f; | |
214 | sector_div(cylinders, hg->heads * hg->sectors); | |
215 | hg->cylinders = cylinders; | |
216 | if ((sector_t)(hg->cylinders + 1) * hg->heads * hg->sectors < nsect) | |
217 | hg->cylinders = 0xffff; | |
218 | return 0; | |
219 | } | |
220 | ||
a63c848b | 221 | static int blkif_ioctl(struct block_device *bdev, fmode_t mode, |
62aa0054 | 222 | unsigned command, unsigned long argument) |
440a01a7 | 223 | { |
a63c848b | 224 | struct blkfront_info *info = bdev->bd_disk->private_data; |
440a01a7 CL |
225 | int i; |
226 | ||
227 | dev_dbg(&info->xbdev->dev, "command: 0x%x, argument: 0x%lx\n", | |
228 | command, (long)argument); | |
229 | ||
230 | switch (command) { | |
231 | case CDROMMULTISESSION: | |
232 | dev_dbg(&info->xbdev->dev, "FIXME: support multisession CDs later\n"); | |
233 | for (i = 0; i < sizeof(struct cdrom_multisession); i++) | |
234 | if (put_user(0, (char __user *)(argument + i))) | |
235 | return -EFAULT; | |
236 | return 0; | |
237 | ||
238 | case CDROM_GET_CAPABILITY: { | |
239 | struct gendisk *gd = info->gd; | |
240 | if (gd->flags & GENHD_FL_CD) | |
241 | return 0; | |
242 | return -EINVAL; | |
243 | } | |
244 | ||
245 | default: | |
246 | /*printk(KERN_ALERT "ioctl %08x not supported by Xen blkdev\n", | |
247 | command);*/ | |
248 | return -EINVAL; /* same return as native Linux */ | |
249 | } | |
250 | ||
251 | return 0; | |
252 | } | |
253 | ||
9f27ee59 | 254 | /* |
c64e38ea | 255 | * Generate a Xen blkfront IO request from a blk layer request. Reads |
edf6ef59 | 256 | * and writes are handled as expected. |
9f27ee59 | 257 | * |
c64e38ea | 258 | * @req: a request struct |
9f27ee59 JF |
259 | */ |
260 | static int blkif_queue_request(struct request *req) | |
261 | { | |
262 | struct blkfront_info *info = req->rq_disk->private_data; | |
263 | unsigned long buffer_mfn; | |
264 | struct blkif_request *ring_req; | |
9f27ee59 JF |
265 | unsigned long id; |
266 | unsigned int fsect, lsect; | |
9e973e64 | 267 | int i, ref; |
9f27ee59 | 268 | grant_ref_t gref_head; |
9e973e64 | 269 | struct scatterlist *sg; |
9f27ee59 JF |
270 | |
271 | if (unlikely(info->connected != BLKIF_STATE_CONNECTED)) | |
272 | return 1; | |
273 | ||
274 | if (gnttab_alloc_grant_references( | |
275 | BLKIF_MAX_SEGMENTS_PER_REQUEST, &gref_head) < 0) { | |
276 | gnttab_request_free_callback( | |
277 | &info->callback, | |
278 | blkif_restart_queue_callback, | |
279 | info, | |
280 | BLKIF_MAX_SEGMENTS_PER_REQUEST); | |
281 | return 1; | |
282 | } | |
283 | ||
284 | /* Fill out a communications ring structure. */ | |
285 | ring_req = RING_GET_REQUEST(&info->ring, info->ring.req_prod_pvt); | |
286 | id = get_id_from_freelist(info); | |
a945b980 | 287 | info->shadow[id].request = req; |
9f27ee59 | 288 | |
97e36834 | 289 | ring_req->u.rw.id = id; |
51de6952 | 290 | ring_req->u.rw.sector_number = (blkif_sector_t)blk_rq_pos(req); |
97e36834 | 291 | ring_req->u.rw.handle = info->handle; |
9f27ee59 JF |
292 | |
293 | ring_req->operation = rq_data_dir(req) ? | |
294 | BLKIF_OP_WRITE : BLKIF_OP_READ; | |
be2f8373 JF |
295 | |
296 | if (req->cmd_flags & (REQ_FLUSH | REQ_FUA)) { | |
297 | /* | |
edf6ef59 KRW |
298 | * Ideally we can do an unordered flush-to-disk. In case the |
299 | * backend onlysupports barriers, use that. A barrier request | |
be2f8373 JF |
300 | * a superset of FUA, so we can implement it the same |
301 | * way. (It's also a FLUSH+FUA, since it is | |
302 | * guaranteed ordered WRT previous writes.) | |
303 | */ | |
edf6ef59 | 304 | ring_req->operation = info->flush_op; |
be2f8373 | 305 | } |
9f27ee59 | 306 | |
5ea42986 | 307 | if (unlikely(req->cmd_flags & (REQ_DISCARD | REQ_SECURE))) { |
ed30bf31 LD |
308 | /* id, sector_number and handle are set above. */ |
309 | ring_req->operation = BLKIF_OP_DISCARD; | |
ed30bf31 | 310 | ring_req->u.discard.nr_sectors = blk_rq_sectors(req); |
5ea42986 KRW |
311 | if ((req->cmd_flags & REQ_SECURE) && info->feature_secdiscard) |
312 | ring_req->u.discard.flag = BLKIF_DISCARD_SECURE; | |
313 | else | |
314 | ring_req->u.discard.flag = 0; | |
ed30bf31 | 315 | } else { |
97e36834 KRW |
316 | ring_req->u.rw.nr_segments = blk_rq_map_sg(req->q, req, |
317 | info->sg); | |
318 | BUG_ON(ring_req->u.rw.nr_segments > | |
319 | BLKIF_MAX_SEGMENTS_PER_REQUEST); | |
9e973e64 | 320 | |
97e36834 | 321 | for_each_sg(info->sg, sg, ring_req->u.rw.nr_segments, i) { |
ed30bf31 LD |
322 | buffer_mfn = pfn_to_mfn(page_to_pfn(sg_page(sg))); |
323 | fsect = sg->offset >> 9; | |
324 | lsect = fsect + (sg->length >> 9) - 1; | |
325 | /* install a grant reference. */ | |
326 | ref = gnttab_claim_grant_reference(&gref_head); | |
327 | BUG_ON(ref == -ENOSPC); | |
6c92e699 | 328 | |
ed30bf31 LD |
329 | gnttab_grant_foreign_access_ref( |
330 | ref, | |
331 | info->xbdev->otherend_id, | |
332 | buffer_mfn, | |
333 | rq_data_dir(req)); | |
334 | ||
335 | info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn); | |
336 | ring_req->u.rw.seg[i] = | |
337 | (struct blkif_request_segment) { | |
338 | .gref = ref, | |
339 | .first_sect = fsect, | |
340 | .last_sect = lsect }; | |
341 | } | |
9f27ee59 JF |
342 | } |
343 | ||
344 | info->ring.req_prod_pvt++; | |
345 | ||
346 | /* Keep a private copy so we can reissue requests when recovering. */ | |
347 | info->shadow[id].req = *ring_req; | |
348 | ||
349 | gnttab_free_grant_references(gref_head); | |
350 | ||
351 | return 0; | |
352 | } | |
353 | ||
354 | ||
355 | static inline void flush_requests(struct blkfront_info *info) | |
356 | { | |
357 | int notify; | |
358 | ||
359 | RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&info->ring, notify); | |
360 | ||
361 | if (notify) | |
362 | notify_remote_via_irq(info->irq); | |
363 | } | |
364 | ||
365 | /* | |
366 | * do_blkif_request | |
367 | * read a block; request is in a request queue | |
368 | */ | |
165125e1 | 369 | static void do_blkif_request(struct request_queue *rq) |
9f27ee59 JF |
370 | { |
371 | struct blkfront_info *info = NULL; | |
372 | struct request *req; | |
373 | int queued; | |
374 | ||
375 | pr_debug("Entered do_blkif_request\n"); | |
376 | ||
377 | queued = 0; | |
378 | ||
9934c8c0 | 379 | while ((req = blk_peek_request(rq)) != NULL) { |
9f27ee59 | 380 | info = req->rq_disk->private_data; |
9f27ee59 JF |
381 | |
382 | if (RING_FULL(&info->ring)) | |
383 | goto wait; | |
384 | ||
9934c8c0 | 385 | blk_start_request(req); |
296b2f6a | 386 | |
d11e6158 KRW |
387 | if ((req->cmd_type != REQ_TYPE_FS) || |
388 | ((req->cmd_flags & (REQ_FLUSH | REQ_FUA)) && | |
389 | !info->flush_op)) { | |
296b2f6a TH |
390 | __blk_end_request_all(req, -EIO); |
391 | continue; | |
392 | } | |
393 | ||
9f27ee59 | 394 | pr_debug("do_blk_req %p: cmd %p, sec %lx, " |
83096ebf TH |
395 | "(%u/%u) buffer:%p [%s]\n", |
396 | req, req->cmd, (unsigned long)blk_rq_pos(req), | |
397 | blk_rq_cur_sectors(req), blk_rq_sectors(req), | |
398 | req->buffer, rq_data_dir(req) ? "write" : "read"); | |
9f27ee59 | 399 | |
9f27ee59 JF |
400 | if (blkif_queue_request(req)) { |
401 | blk_requeue_request(rq, req); | |
402 | wait: | |
403 | /* Avoid pointless unplugs. */ | |
404 | blk_stop_queue(rq); | |
405 | break; | |
406 | } | |
407 | ||
408 | queued++; | |
409 | } | |
410 | ||
411 | if (queued != 0) | |
412 | flush_requests(info); | |
413 | } | |
414 | ||
415 | static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size) | |
416 | { | |
165125e1 | 417 | struct request_queue *rq; |
ed30bf31 | 418 | struct blkfront_info *info = gd->private_data; |
9f27ee59 | 419 | |
3467811e | 420 | rq = blk_init_queue(do_blkif_request, &info->io_lock); |
9f27ee59 JF |
421 | if (rq == NULL) |
422 | return -1; | |
423 | ||
66d352e1 | 424 | queue_flag_set_unlocked(QUEUE_FLAG_VIRT, rq); |
9f27ee59 | 425 | |
ed30bf31 LD |
426 | if (info->feature_discard) { |
427 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, rq); | |
428 | blk_queue_max_discard_sectors(rq, get_capacity(gd)); | |
429 | rq->limits.discard_granularity = info->discard_granularity; | |
430 | rq->limits.discard_alignment = info->discard_alignment; | |
5ea42986 KRW |
431 | if (info->feature_secdiscard) |
432 | queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD, rq); | |
ed30bf31 LD |
433 | } |
434 | ||
9f27ee59 | 435 | /* Hard sector size and max sectors impersonate the equiv. hardware. */ |
e1defc4f | 436 | blk_queue_logical_block_size(rq, sector_size); |
086fa5ff | 437 | blk_queue_max_hw_sectors(rq, 512); |
9f27ee59 JF |
438 | |
439 | /* Each segment in a request is up to an aligned page in size. */ | |
440 | blk_queue_segment_boundary(rq, PAGE_SIZE - 1); | |
441 | blk_queue_max_segment_size(rq, PAGE_SIZE); | |
442 | ||
443 | /* Ensure a merged request will fit in a single I/O ring slot. */ | |
8a78362c | 444 | blk_queue_max_segments(rq, BLKIF_MAX_SEGMENTS_PER_REQUEST); |
9f27ee59 JF |
445 | |
446 | /* Make sure buffer addresses are sector-aligned. */ | |
447 | blk_queue_dma_alignment(rq, 511); | |
448 | ||
1c91fe1a IC |
449 | /* Make sure we don't use bounce buffers. */ |
450 | blk_queue_bounce_limit(rq, BLK_BOUNCE_ANY); | |
451 | ||
9f27ee59 JF |
452 | gd->queue = rq; |
453 | ||
454 | return 0; | |
455 | } | |
456 | ||
457 | ||
4913efe4 | 458 | static void xlvbd_flush(struct blkfront_info *info) |
9f27ee59 | 459 | { |
4913efe4 | 460 | blk_queue_flush(info->rq, info->feature_flush); |
edf6ef59 | 461 | printk(KERN_INFO "blkfront: %s: %s: %s\n", |
4913efe4 | 462 | info->gd->disk_name, |
edf6ef59 KRW |
463 | info->flush_op == BLKIF_OP_WRITE_BARRIER ? |
464 | "barrier" : (info->flush_op == BLKIF_OP_FLUSH_DISKCACHE ? | |
465 | "flush diskcache" : "barrier or flush"), | |
4913efe4 | 466 | info->feature_flush ? "enabled" : "disabled"); |
9f27ee59 JF |
467 | } |
468 | ||
c80a4209 SS |
469 | static int xen_translate_vdev(int vdevice, int *minor, unsigned int *offset) |
470 | { | |
471 | int major; | |
472 | major = BLKIF_MAJOR(vdevice); | |
473 | *minor = BLKIF_MINOR(vdevice); | |
474 | switch (major) { | |
475 | case XEN_IDE0_MAJOR: | |
476 | *offset = (*minor / 64) + EMULATED_HD_DISK_NAME_OFFSET; | |
477 | *minor = ((*minor / 64) * PARTS_PER_DISK) + | |
478 | EMULATED_HD_DISK_MINOR_OFFSET; | |
479 | break; | |
480 | case XEN_IDE1_MAJOR: | |
481 | *offset = (*minor / 64) + 2 + EMULATED_HD_DISK_NAME_OFFSET; | |
482 | *minor = (((*minor / 64) + 2) * PARTS_PER_DISK) + | |
483 | EMULATED_HD_DISK_MINOR_OFFSET; | |
484 | break; | |
485 | case XEN_SCSI_DISK0_MAJOR: | |
486 | *offset = (*minor / PARTS_PER_DISK) + EMULATED_SD_DISK_NAME_OFFSET; | |
487 | *minor = *minor + EMULATED_SD_DISK_MINOR_OFFSET; | |
488 | break; | |
489 | case XEN_SCSI_DISK1_MAJOR: | |
490 | case XEN_SCSI_DISK2_MAJOR: | |
491 | case XEN_SCSI_DISK3_MAJOR: | |
492 | case XEN_SCSI_DISK4_MAJOR: | |
493 | case XEN_SCSI_DISK5_MAJOR: | |
494 | case XEN_SCSI_DISK6_MAJOR: | |
495 | case XEN_SCSI_DISK7_MAJOR: | |
496 | *offset = (*minor / PARTS_PER_DISK) + | |
497 | ((major - XEN_SCSI_DISK1_MAJOR + 1) * 16) + | |
498 | EMULATED_SD_DISK_NAME_OFFSET; | |
499 | *minor = *minor + | |
500 | ((major - XEN_SCSI_DISK1_MAJOR + 1) * 16 * PARTS_PER_DISK) + | |
501 | EMULATED_SD_DISK_MINOR_OFFSET; | |
502 | break; | |
503 | case XEN_SCSI_DISK8_MAJOR: | |
504 | case XEN_SCSI_DISK9_MAJOR: | |
505 | case XEN_SCSI_DISK10_MAJOR: | |
506 | case XEN_SCSI_DISK11_MAJOR: | |
507 | case XEN_SCSI_DISK12_MAJOR: | |
508 | case XEN_SCSI_DISK13_MAJOR: | |
509 | case XEN_SCSI_DISK14_MAJOR: | |
510 | case XEN_SCSI_DISK15_MAJOR: | |
511 | *offset = (*minor / PARTS_PER_DISK) + | |
512 | ((major - XEN_SCSI_DISK8_MAJOR + 8) * 16) + | |
513 | EMULATED_SD_DISK_NAME_OFFSET; | |
514 | *minor = *minor + | |
515 | ((major - XEN_SCSI_DISK8_MAJOR + 8) * 16 * PARTS_PER_DISK) + | |
516 | EMULATED_SD_DISK_MINOR_OFFSET; | |
517 | break; | |
518 | case XENVBD_MAJOR: | |
519 | *offset = *minor / PARTS_PER_DISK; | |
520 | break; | |
521 | default: | |
522 | printk(KERN_WARNING "blkfront: your disk configuration is " | |
523 | "incorrect, please use an xvd device instead\n"); | |
524 | return -ENODEV; | |
525 | } | |
526 | return 0; | |
527 | } | |
9f27ee59 | 528 | |
e77c78c0 JB |
529 | static char *encode_disk_name(char *ptr, unsigned int n) |
530 | { | |
531 | if (n >= 26) | |
532 | ptr = encode_disk_name(ptr, n / 26 - 1); | |
533 | *ptr = 'a' + n % 26; | |
534 | return ptr + 1; | |
535 | } | |
536 | ||
9246b5f0 CL |
537 | static int xlvbd_alloc_gendisk(blkif_sector_t capacity, |
538 | struct blkfront_info *info, | |
539 | u16 vdisk_info, u16 sector_size) | |
9f27ee59 JF |
540 | { |
541 | struct gendisk *gd; | |
542 | int nr_minors = 1; | |
c80a4209 | 543 | int err; |
9246b5f0 CL |
544 | unsigned int offset; |
545 | int minor; | |
546 | int nr_parts; | |
e77c78c0 | 547 | char *ptr; |
9f27ee59 JF |
548 | |
549 | BUG_ON(info->gd != NULL); | |
550 | BUG_ON(info->rq != NULL); | |
551 | ||
9246b5f0 CL |
552 | if ((info->vdevice>>EXT_SHIFT) > 1) { |
553 | /* this is above the extended range; something is wrong */ | |
554 | printk(KERN_WARNING "blkfront: vdevice 0x%x is above the extended range; ignoring\n", info->vdevice); | |
555 | return -ENODEV; | |
556 | } | |
557 | ||
558 | if (!VDEV_IS_EXTENDED(info->vdevice)) { | |
c80a4209 SS |
559 | err = xen_translate_vdev(info->vdevice, &minor, &offset); |
560 | if (err) | |
561 | return err; | |
562 | nr_parts = PARTS_PER_DISK; | |
9246b5f0 CL |
563 | } else { |
564 | minor = BLKIF_MINOR_EXT(info->vdevice); | |
565 | nr_parts = PARTS_PER_EXT_DISK; | |
c80a4209 | 566 | offset = minor / nr_parts; |
89153b5c | 567 | if (xen_hvm_domain() && offset < EMULATED_HD_DISK_NAME_OFFSET + 4) |
c80a4209 SS |
568 | printk(KERN_WARNING "blkfront: vdevice 0x%x might conflict with " |
569 | "emulated IDE disks,\n\t choose an xvd device name" | |
570 | "from xvde on\n", info->vdevice); | |
9246b5f0 | 571 | } |
e77c78c0 JB |
572 | if (minor >> MINORBITS) { |
573 | pr_warn("blkfront: %#x's minor (%#x) out of range; ignoring\n", | |
574 | info->vdevice, minor); | |
575 | return -ENODEV; | |
576 | } | |
9246b5f0 CL |
577 | |
578 | if ((minor % nr_parts) == 0) | |
579 | nr_minors = nr_parts; | |
9f27ee59 | 580 | |
0e345826 JB |
581 | err = xlbd_reserve_minors(minor, nr_minors); |
582 | if (err) | |
583 | goto out; | |
584 | err = -ENODEV; | |
585 | ||
9f27ee59 JF |
586 | gd = alloc_disk(nr_minors); |
587 | if (gd == NULL) | |
0e345826 | 588 | goto release; |
9f27ee59 | 589 | |
e77c78c0 JB |
590 | strcpy(gd->disk_name, DEV_NAME); |
591 | ptr = encode_disk_name(gd->disk_name + sizeof(DEV_NAME) - 1, offset); | |
592 | BUG_ON(ptr >= gd->disk_name + DISK_NAME_LEN); | |
593 | if (nr_minors > 1) | |
594 | *ptr = 0; | |
595 | else | |
596 | snprintf(ptr, gd->disk_name + DISK_NAME_LEN - ptr, | |
597 | "%d", minor & (nr_parts - 1)); | |
9f27ee59 JF |
598 | |
599 | gd->major = XENVBD_MAJOR; | |
600 | gd->first_minor = minor; | |
601 | gd->fops = &xlvbd_block_fops; | |
602 | gd->private_data = info; | |
603 | gd->driverfs_dev = &(info->xbdev->dev); | |
604 | set_capacity(gd, capacity); | |
605 | ||
606 | if (xlvbd_init_blk_queue(gd, sector_size)) { | |
607 | del_gendisk(gd); | |
0e345826 | 608 | goto release; |
9f27ee59 JF |
609 | } |
610 | ||
611 | info->rq = gd->queue; | |
612 | info->gd = gd; | |
613 | ||
4913efe4 | 614 | xlvbd_flush(info); |
9f27ee59 JF |
615 | |
616 | if (vdisk_info & VDISK_READONLY) | |
617 | set_disk_ro(gd, 1); | |
618 | ||
619 | if (vdisk_info & VDISK_REMOVABLE) | |
620 | gd->flags |= GENHD_FL_REMOVABLE; | |
621 | ||
622 | if (vdisk_info & VDISK_CDROM) | |
623 | gd->flags |= GENHD_FL_CD; | |
624 | ||
625 | return 0; | |
626 | ||
0e345826 JB |
627 | release: |
628 | xlbd_release_minors(minor, nr_minors); | |
9f27ee59 JF |
629 | out: |
630 | return err; | |
631 | } | |
632 | ||
a66b5aeb DS |
633 | static void xlvbd_release_gendisk(struct blkfront_info *info) |
634 | { | |
635 | unsigned int minor, nr_minors; | |
636 | unsigned long flags; | |
637 | ||
638 | if (info->rq == NULL) | |
639 | return; | |
640 | ||
3467811e | 641 | spin_lock_irqsave(&info->io_lock, flags); |
a66b5aeb DS |
642 | |
643 | /* No more blkif_request(). */ | |
644 | blk_stop_queue(info->rq); | |
645 | ||
646 | /* No more gnttab callback work. */ | |
647 | gnttab_cancel_free_callback(&info->callback); | |
3467811e | 648 | spin_unlock_irqrestore(&info->io_lock, flags); |
a66b5aeb DS |
649 | |
650 | /* Flush gnttab callback work. Must be done with no locks held. */ | |
30d65030 | 651 | flush_work_sync(&info->work); |
a66b5aeb DS |
652 | |
653 | del_gendisk(info->gd); | |
654 | ||
655 | minor = info->gd->first_minor; | |
656 | nr_minors = info->gd->minors; | |
657 | xlbd_release_minors(minor, nr_minors); | |
658 | ||
659 | blk_cleanup_queue(info->rq); | |
660 | info->rq = NULL; | |
661 | ||
662 | put_disk(info->gd); | |
663 | info->gd = NULL; | |
664 | } | |
665 | ||
9f27ee59 JF |
666 | static void kick_pending_request_queues(struct blkfront_info *info) |
667 | { | |
668 | if (!RING_FULL(&info->ring)) { | |
669 | /* Re-enable calldowns. */ | |
670 | blk_start_queue(info->rq); | |
671 | /* Kick things off immediately. */ | |
672 | do_blkif_request(info->rq); | |
673 | } | |
674 | } | |
675 | ||
676 | static void blkif_restart_queue(struct work_struct *work) | |
677 | { | |
678 | struct blkfront_info *info = container_of(work, struct blkfront_info, work); | |
679 | ||
3467811e | 680 | spin_lock_irq(&info->io_lock); |
9f27ee59 JF |
681 | if (info->connected == BLKIF_STATE_CONNECTED) |
682 | kick_pending_request_queues(info); | |
3467811e | 683 | spin_unlock_irq(&info->io_lock); |
9f27ee59 JF |
684 | } |
685 | ||
686 | static void blkif_free(struct blkfront_info *info, int suspend) | |
687 | { | |
688 | /* Prevent new requests being issued until we fix things up. */ | |
3467811e | 689 | spin_lock_irq(&info->io_lock); |
9f27ee59 JF |
690 | info->connected = suspend ? |
691 | BLKIF_STATE_SUSPENDED : BLKIF_STATE_DISCONNECTED; | |
692 | /* No more blkif_request(). */ | |
693 | if (info->rq) | |
694 | blk_stop_queue(info->rq); | |
695 | /* No more gnttab callback work. */ | |
696 | gnttab_cancel_free_callback(&info->callback); | |
3467811e | 697 | spin_unlock_irq(&info->io_lock); |
9f27ee59 JF |
698 | |
699 | /* Flush gnttab callback work. Must be done with no locks held. */ | |
30d65030 | 700 | flush_work_sync(&info->work); |
9f27ee59 JF |
701 | |
702 | /* Free resources associated with old device channel. */ | |
703 | if (info->ring_ref != GRANT_INVALID_REF) { | |
704 | gnttab_end_foreign_access(info->ring_ref, 0, | |
705 | (unsigned long)info->ring.sring); | |
706 | info->ring_ref = GRANT_INVALID_REF; | |
707 | info->ring.sring = NULL; | |
708 | } | |
709 | if (info->irq) | |
710 | unbind_from_irqhandler(info->irq, info); | |
711 | info->evtchn = info->irq = 0; | |
712 | ||
713 | } | |
714 | ||
715 | static void blkif_completion(struct blk_shadow *s) | |
716 | { | |
717 | int i; | |
5ea42986 KRW |
718 | /* Do not let BLKIF_OP_DISCARD as nr_segment is in the same place |
719 | * flag. */ | |
97e36834 | 720 | for (i = 0; i < s->req.u.rw.nr_segments; i++) |
51de6952 | 721 | gnttab_end_foreign_access(s->req.u.rw.seg[i].gref, 0, 0UL); |
9f27ee59 JF |
722 | } |
723 | ||
724 | static irqreturn_t blkif_interrupt(int irq, void *dev_id) | |
725 | { | |
726 | struct request *req; | |
727 | struct blkif_response *bret; | |
728 | RING_IDX i, rp; | |
729 | unsigned long flags; | |
730 | struct blkfront_info *info = (struct blkfront_info *)dev_id; | |
f530f036 | 731 | int error; |
9f27ee59 | 732 | |
3467811e | 733 | spin_lock_irqsave(&info->io_lock, flags); |
9f27ee59 JF |
734 | |
735 | if (unlikely(info->connected != BLKIF_STATE_CONNECTED)) { | |
3467811e | 736 | spin_unlock_irqrestore(&info->io_lock, flags); |
9f27ee59 JF |
737 | return IRQ_HANDLED; |
738 | } | |
739 | ||
740 | again: | |
741 | rp = info->ring.sring->rsp_prod; | |
742 | rmb(); /* Ensure we see queued responses up to 'rp'. */ | |
743 | ||
744 | for (i = info->ring.rsp_cons; i != rp; i++) { | |
745 | unsigned long id; | |
9f27ee59 JF |
746 | |
747 | bret = RING_GET_RESPONSE(&info->ring, i); | |
748 | id = bret->id; | |
a945b980 | 749 | req = info->shadow[id].request; |
9f27ee59 | 750 | |
5ea42986 KRW |
751 | if (bret->operation != BLKIF_OP_DISCARD) |
752 | blkif_completion(&info->shadow[id]); | |
9f27ee59 JF |
753 | |
754 | add_id_to_freelist(info, id); | |
755 | ||
f530f036 | 756 | error = (bret->status == BLKIF_RSP_OKAY) ? 0 : -EIO; |
9f27ee59 | 757 | switch (bret->operation) { |
ed30bf31 LD |
758 | case BLKIF_OP_DISCARD: |
759 | if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) { | |
760 | struct request_queue *rq = info->rq; | |
761 | printk(KERN_WARNING "blkfront: %s: discard op failed\n", | |
762 | info->gd->disk_name); | |
763 | error = -EOPNOTSUPP; | |
764 | info->feature_discard = 0; | |
5ea42986 | 765 | info->feature_secdiscard = 0; |
ed30bf31 | 766 | queue_flag_clear(QUEUE_FLAG_DISCARD, rq); |
5ea42986 | 767 | queue_flag_clear(QUEUE_FLAG_SECDISCARD, rq); |
ed30bf31 LD |
768 | } |
769 | __blk_end_request_all(req, error); | |
770 | break; | |
edf6ef59 | 771 | case BLKIF_OP_FLUSH_DISKCACHE: |
9f27ee59 JF |
772 | case BLKIF_OP_WRITE_BARRIER: |
773 | if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) { | |
edf6ef59 KRW |
774 | printk(KERN_WARNING "blkfront: %s: write %s op failed\n", |
775 | info->flush_op == BLKIF_OP_WRITE_BARRIER ? | |
776 | "barrier" : "flush disk cache", | |
9f27ee59 | 777 | info->gd->disk_name); |
f530f036 | 778 | error = -EOPNOTSUPP; |
dcb8baec JF |
779 | } |
780 | if (unlikely(bret->status == BLKIF_RSP_ERROR && | |
97e36834 | 781 | info->shadow[id].req.u.rw.nr_segments == 0)) { |
edf6ef59 KRW |
782 | printk(KERN_WARNING "blkfront: %s: empty write %s op failed\n", |
783 | info->flush_op == BLKIF_OP_WRITE_BARRIER ? | |
784 | "barrier" : "flush disk cache", | |
dcb8baec JF |
785 | info->gd->disk_name); |
786 | error = -EOPNOTSUPP; | |
787 | } | |
788 | if (unlikely(error)) { | |
789 | if (error == -EOPNOTSUPP) | |
790 | error = 0; | |
4913efe4 | 791 | info->feature_flush = 0; |
edf6ef59 | 792 | info->flush_op = 0; |
4913efe4 | 793 | xlvbd_flush(info); |
9f27ee59 JF |
794 | } |
795 | /* fall through */ | |
796 | case BLKIF_OP_READ: | |
797 | case BLKIF_OP_WRITE: | |
798 | if (unlikely(bret->status != BLKIF_RSP_OKAY)) | |
799 | dev_dbg(&info->xbdev->dev, "Bad return from blkdev data " | |
800 | "request: %x\n", bret->status); | |
801 | ||
40cbbb78 | 802 | __blk_end_request_all(req, error); |
9f27ee59 JF |
803 | break; |
804 | default: | |
805 | BUG(); | |
806 | } | |
807 | } | |
808 | ||
809 | info->ring.rsp_cons = i; | |
810 | ||
811 | if (i != info->ring.req_prod_pvt) { | |
812 | int more_to_do; | |
813 | RING_FINAL_CHECK_FOR_RESPONSES(&info->ring, more_to_do); | |
814 | if (more_to_do) | |
815 | goto again; | |
816 | } else | |
817 | info->ring.sring->rsp_event = i + 1; | |
818 | ||
819 | kick_pending_request_queues(info); | |
820 | ||
3467811e | 821 | spin_unlock_irqrestore(&info->io_lock, flags); |
9f27ee59 JF |
822 | |
823 | return IRQ_HANDLED; | |
824 | } | |
825 | ||
826 | ||
827 | static int setup_blkring(struct xenbus_device *dev, | |
828 | struct blkfront_info *info) | |
829 | { | |
830 | struct blkif_sring *sring; | |
831 | int err; | |
832 | ||
833 | info->ring_ref = GRANT_INVALID_REF; | |
834 | ||
a144ff09 | 835 | sring = (struct blkif_sring *)__get_free_page(GFP_NOIO | __GFP_HIGH); |
9f27ee59 JF |
836 | if (!sring) { |
837 | xenbus_dev_fatal(dev, -ENOMEM, "allocating shared ring"); | |
838 | return -ENOMEM; | |
839 | } | |
840 | SHARED_RING_INIT(sring); | |
841 | FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE); | |
9e973e64 JA |
842 | |
843 | sg_init_table(info->sg, BLKIF_MAX_SEGMENTS_PER_REQUEST); | |
9f27ee59 JF |
844 | |
845 | err = xenbus_grant_ring(dev, virt_to_mfn(info->ring.sring)); | |
846 | if (err < 0) { | |
847 | free_page((unsigned long)sring); | |
848 | info->ring.sring = NULL; | |
849 | goto fail; | |
850 | } | |
851 | info->ring_ref = err; | |
852 | ||
853 | err = xenbus_alloc_evtchn(dev, &info->evtchn); | |
854 | if (err) | |
855 | goto fail; | |
856 | ||
857 | err = bind_evtchn_to_irqhandler(info->evtchn, | |
858 | blkif_interrupt, | |
859 | IRQF_SAMPLE_RANDOM, "blkif", info); | |
860 | if (err <= 0) { | |
861 | xenbus_dev_fatal(dev, err, | |
862 | "bind_evtchn_to_irqhandler failed"); | |
863 | goto fail; | |
864 | } | |
865 | info->irq = err; | |
866 | ||
867 | return 0; | |
868 | fail: | |
869 | blkif_free(info, 0); | |
870 | return err; | |
871 | } | |
872 | ||
873 | ||
874 | /* Common code used when first setting up, and when resuming. */ | |
203fd61f | 875 | static int talk_to_blkback(struct xenbus_device *dev, |
9f27ee59 JF |
876 | struct blkfront_info *info) |
877 | { | |
878 | const char *message = NULL; | |
879 | struct xenbus_transaction xbt; | |
880 | int err; | |
881 | ||
882 | /* Create shared ring, alloc event channel. */ | |
883 | err = setup_blkring(dev, info); | |
884 | if (err) | |
885 | goto out; | |
886 | ||
887 | again: | |
888 | err = xenbus_transaction_start(&xbt); | |
889 | if (err) { | |
890 | xenbus_dev_fatal(dev, err, "starting transaction"); | |
891 | goto destroy_blkring; | |
892 | } | |
893 | ||
894 | err = xenbus_printf(xbt, dev->nodename, | |
895 | "ring-ref", "%u", info->ring_ref); | |
896 | if (err) { | |
897 | message = "writing ring-ref"; | |
898 | goto abort_transaction; | |
899 | } | |
900 | err = xenbus_printf(xbt, dev->nodename, | |
901 | "event-channel", "%u", info->evtchn); | |
902 | if (err) { | |
903 | message = "writing event-channel"; | |
904 | goto abort_transaction; | |
905 | } | |
3e334239 MA |
906 | err = xenbus_printf(xbt, dev->nodename, "protocol", "%s", |
907 | XEN_IO_PROTO_ABI_NATIVE); | |
908 | if (err) { | |
909 | message = "writing protocol"; | |
910 | goto abort_transaction; | |
911 | } | |
9f27ee59 JF |
912 | |
913 | err = xenbus_transaction_end(xbt, 0); | |
914 | if (err) { | |
915 | if (err == -EAGAIN) | |
916 | goto again; | |
917 | xenbus_dev_fatal(dev, err, "completing transaction"); | |
918 | goto destroy_blkring; | |
919 | } | |
920 | ||
921 | xenbus_switch_state(dev, XenbusStateInitialised); | |
922 | ||
923 | return 0; | |
924 | ||
925 | abort_transaction: | |
926 | xenbus_transaction_end(xbt, 1); | |
927 | if (message) | |
928 | xenbus_dev_fatal(dev, err, "%s", message); | |
929 | destroy_blkring: | |
930 | blkif_free(info, 0); | |
931 | out: | |
932 | return err; | |
933 | } | |
934 | ||
9f27ee59 JF |
935 | /** |
936 | * Entry point to this code when a new device is created. Allocate the basic | |
937 | * structures and the ring buffer for communication with the backend, and | |
938 | * inform the backend of the appropriate details for those. Switch to | |
939 | * Initialised state. | |
940 | */ | |
941 | static int blkfront_probe(struct xenbus_device *dev, | |
942 | const struct xenbus_device_id *id) | |
943 | { | |
944 | int err, vdevice, i; | |
945 | struct blkfront_info *info; | |
946 | ||
947 | /* FIXME: Use dynamic device id if this is not set. */ | |
948 | err = xenbus_scanf(XBT_NIL, dev->nodename, | |
949 | "virtual-device", "%i", &vdevice); | |
950 | if (err != 1) { | |
9246b5f0 CL |
951 | /* go looking in the extended area instead */ |
952 | err = xenbus_scanf(XBT_NIL, dev->nodename, "virtual-device-ext", | |
953 | "%i", &vdevice); | |
954 | if (err != 1) { | |
955 | xenbus_dev_fatal(dev, err, "reading virtual-device"); | |
956 | return err; | |
957 | } | |
9f27ee59 JF |
958 | } |
959 | ||
b98a409b SS |
960 | if (xen_hvm_domain()) { |
961 | char *type; | |
962 | int len; | |
963 | /* no unplug has been done: do not hook devices != xen vbds */ | |
1dc7ce99 | 964 | if (xen_platform_pci_unplug & XEN_UNPLUG_UNNECESSARY) { |
b98a409b SS |
965 | int major; |
966 | ||
967 | if (!VDEV_IS_EXTENDED(vdevice)) | |
968 | major = BLKIF_MAJOR(vdevice); | |
969 | else | |
970 | major = XENVBD_MAJOR; | |
971 | ||
972 | if (major != XENVBD_MAJOR) { | |
973 | printk(KERN_INFO | |
974 | "%s: HVM does not support vbd %d as xen block device\n", | |
975 | __FUNCTION__, vdevice); | |
976 | return -ENODEV; | |
977 | } | |
978 | } | |
979 | /* do not create a PV cdrom device if we are an HVM guest */ | |
980 | type = xenbus_read(XBT_NIL, dev->nodename, "device-type", &len); | |
981 | if (IS_ERR(type)) | |
982 | return -ENODEV; | |
983 | if (strncmp(type, "cdrom", 5) == 0) { | |
984 | kfree(type); | |
c1c5413a SS |
985 | return -ENODEV; |
986 | } | |
b98a409b | 987 | kfree(type); |
c1c5413a | 988 | } |
9f27ee59 JF |
989 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
990 | if (!info) { | |
991 | xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure"); | |
992 | return -ENOMEM; | |
993 | } | |
994 | ||
b70f5fa0 | 995 | mutex_init(&info->mutex); |
3467811e | 996 | spin_lock_init(&info->io_lock); |
9f27ee59 JF |
997 | info->xbdev = dev; |
998 | info->vdevice = vdevice; | |
999 | info->connected = BLKIF_STATE_DISCONNECTED; | |
1000 | INIT_WORK(&info->work, blkif_restart_queue); | |
1001 | ||
1002 | for (i = 0; i < BLK_RING_SIZE; i++) | |
97e36834 KRW |
1003 | info->shadow[i].req.u.rw.id = i+1; |
1004 | info->shadow[BLK_RING_SIZE-1].req.u.rw.id = 0x0fffffff; | |
9f27ee59 JF |
1005 | |
1006 | /* Front end dir is a number, which is used as the id. */ | |
1007 | info->handle = simple_strtoul(strrchr(dev->nodename, '/')+1, NULL, 0); | |
a1b4b12b | 1008 | dev_set_drvdata(&dev->dev, info); |
9f27ee59 | 1009 | |
203fd61f | 1010 | err = talk_to_blkback(dev, info); |
9f27ee59 JF |
1011 | if (err) { |
1012 | kfree(info); | |
a1b4b12b | 1013 | dev_set_drvdata(&dev->dev, NULL); |
9f27ee59 JF |
1014 | return err; |
1015 | } | |
1016 | ||
1017 | return 0; | |
1018 | } | |
1019 | ||
1020 | ||
1021 | static int blkif_recover(struct blkfront_info *info) | |
1022 | { | |
1023 | int i; | |
1024 | struct blkif_request *req; | |
1025 | struct blk_shadow *copy; | |
1026 | int j; | |
1027 | ||
1028 | /* Stage 1: Make a safe copy of the shadow state. */ | |
a144ff09 IC |
1029 | copy = kmalloc(sizeof(info->shadow), |
1030 | GFP_NOIO | __GFP_REPEAT | __GFP_HIGH); | |
9f27ee59 JF |
1031 | if (!copy) |
1032 | return -ENOMEM; | |
1033 | memcpy(copy, info->shadow, sizeof(info->shadow)); | |
1034 | ||
1035 | /* Stage 2: Set up free list. */ | |
1036 | memset(&info->shadow, 0, sizeof(info->shadow)); | |
1037 | for (i = 0; i < BLK_RING_SIZE; i++) | |
97e36834 | 1038 | info->shadow[i].req.u.rw.id = i+1; |
9f27ee59 | 1039 | info->shadow_free = info->ring.req_prod_pvt; |
97e36834 | 1040 | info->shadow[BLK_RING_SIZE-1].req.u.rw.id = 0x0fffffff; |
9f27ee59 JF |
1041 | |
1042 | /* Stage 3: Find pending requests and requeue them. */ | |
1043 | for (i = 0; i < BLK_RING_SIZE; i++) { | |
1044 | /* Not in use? */ | |
a945b980 | 1045 | if (!copy[i].request) |
9f27ee59 JF |
1046 | continue; |
1047 | ||
1048 | /* Grab a request slot and copy shadow state into it. */ | |
1049 | req = RING_GET_REQUEST(&info->ring, info->ring.req_prod_pvt); | |
1050 | *req = copy[i].req; | |
1051 | ||
1052 | /* We get a new request id, and must reset the shadow state. */ | |
97e36834 KRW |
1053 | req->u.rw.id = get_id_from_freelist(info); |
1054 | memcpy(&info->shadow[req->u.rw.id], ©[i], sizeof(copy[i])); | |
9f27ee59 | 1055 | |
5ea42986 | 1056 | if (req->operation != BLKIF_OP_DISCARD) { |
9f27ee59 | 1057 | /* Rewrite any grant references invalidated by susp/resume. */ |
5ea42986 KRW |
1058 | for (j = 0; j < req->u.rw.nr_segments; j++) |
1059 | gnttab_grant_foreign_access_ref( | |
1060 | req->u.rw.seg[j].gref, | |
1061 | info->xbdev->otherend_id, | |
1062 | pfn_to_mfn(info->shadow[req->u.rw.id].frame[j]), | |
1063 | rq_data_dir(info->shadow[req->u.rw.id].request)); | |
1064 | } | |
97e36834 | 1065 | info->shadow[req->u.rw.id].req = *req; |
9f27ee59 JF |
1066 | |
1067 | info->ring.req_prod_pvt++; | |
1068 | } | |
1069 | ||
1070 | kfree(copy); | |
1071 | ||
1072 | xenbus_switch_state(info->xbdev, XenbusStateConnected); | |
1073 | ||
3467811e | 1074 | spin_lock_irq(&info->io_lock); |
9f27ee59 JF |
1075 | |
1076 | /* Now safe for us to use the shared ring */ | |
1077 | info->connected = BLKIF_STATE_CONNECTED; | |
1078 | ||
1079 | /* Send off requeued requests */ | |
1080 | flush_requests(info); | |
1081 | ||
1082 | /* Kick any other new requests queued since we resumed */ | |
1083 | kick_pending_request_queues(info); | |
1084 | ||
3467811e | 1085 | spin_unlock_irq(&info->io_lock); |
9f27ee59 JF |
1086 | |
1087 | return 0; | |
1088 | } | |
1089 | ||
1090 | /** | |
1091 | * We are reconnecting to the backend, due to a suspend/resume, or a backend | |
1092 | * driver restart. We tear down our blkif structure and recreate it, but | |
1093 | * leave the device-layer structures intact so that this is transparent to the | |
1094 | * rest of the kernel. | |
1095 | */ | |
1096 | static int blkfront_resume(struct xenbus_device *dev) | |
1097 | { | |
a1b4b12b | 1098 | struct blkfront_info *info = dev_get_drvdata(&dev->dev); |
9f27ee59 JF |
1099 | int err; |
1100 | ||
1101 | dev_dbg(&dev->dev, "blkfront_resume: %s\n", dev->nodename); | |
1102 | ||
1103 | blkif_free(info, info->connected == BLKIF_STATE_CONNECTED); | |
1104 | ||
203fd61f | 1105 | err = talk_to_blkback(dev, info); |
9f27ee59 JF |
1106 | if (info->connected == BLKIF_STATE_SUSPENDED && !err) |
1107 | err = blkif_recover(info); | |
1108 | ||
1109 | return err; | |
1110 | } | |
1111 | ||
b70f5fa0 DS |
1112 | static void |
1113 | blkfront_closing(struct blkfront_info *info) | |
1114 | { | |
1115 | struct xenbus_device *xbdev = info->xbdev; | |
1116 | struct block_device *bdev = NULL; | |
1117 | ||
1118 | mutex_lock(&info->mutex); | |
1119 | ||
1120 | if (xbdev->state == XenbusStateClosing) { | |
1121 | mutex_unlock(&info->mutex); | |
1122 | return; | |
1123 | } | |
1124 | ||
1125 | if (info->gd) | |
1126 | bdev = bdget_disk(info->gd, 0); | |
1127 | ||
1128 | mutex_unlock(&info->mutex); | |
1129 | ||
1130 | if (!bdev) { | |
1131 | xenbus_frontend_closed(xbdev); | |
1132 | return; | |
1133 | } | |
1134 | ||
1135 | mutex_lock(&bdev->bd_mutex); | |
1136 | ||
7b32d104 | 1137 | if (bdev->bd_openers) { |
b70f5fa0 DS |
1138 | xenbus_dev_error(xbdev, -EBUSY, |
1139 | "Device in use; refusing to close"); | |
1140 | xenbus_switch_state(xbdev, XenbusStateClosing); | |
1141 | } else { | |
1142 | xlvbd_release_gendisk(info); | |
1143 | xenbus_frontend_closed(xbdev); | |
1144 | } | |
1145 | ||
1146 | mutex_unlock(&bdev->bd_mutex); | |
1147 | bdput(bdev); | |
1148 | } | |
9f27ee59 | 1149 | |
ed30bf31 LD |
1150 | static void blkfront_setup_discard(struct blkfront_info *info) |
1151 | { | |
1152 | int err; | |
1153 | char *type; | |
1154 | unsigned int discard_granularity; | |
1155 | unsigned int discard_alignment; | |
5ea42986 | 1156 | unsigned int discard_secure; |
ed30bf31 LD |
1157 | |
1158 | type = xenbus_read(XBT_NIL, info->xbdev->otherend, "type", NULL); | |
1159 | if (IS_ERR(type)) | |
1160 | return; | |
1161 | ||
5ea42986 | 1162 | info->feature_secdiscard = 0; |
ed30bf31 LD |
1163 | if (strncmp(type, "phy", 3) == 0) { |
1164 | err = xenbus_gather(XBT_NIL, info->xbdev->otherend, | |
1165 | "discard-granularity", "%u", &discard_granularity, | |
1166 | "discard-alignment", "%u", &discard_alignment, | |
1167 | NULL); | |
1168 | if (!err) { | |
1169 | info->feature_discard = 1; | |
1170 | info->discard_granularity = discard_granularity; | |
1171 | info->discard_alignment = discard_alignment; | |
1172 | } | |
5ea42986 KRW |
1173 | err = xenbus_gather(XBT_NIL, info->xbdev->otherend, |
1174 | "discard-secure", "%d", &discard_secure, | |
1175 | NULL); | |
1176 | if (!err) | |
1177 | info->feature_secdiscard = discard_secure; | |
1178 | ||
ed30bf31 LD |
1179 | } else if (strncmp(type, "file", 4) == 0) |
1180 | info->feature_discard = 1; | |
1181 | ||
1182 | kfree(type); | |
1183 | } | |
1184 | ||
9f27ee59 JF |
1185 | /* |
1186 | * Invoked when the backend is finally 'ready' (and has told produced | |
1187 | * the details about the physical device - #sectors, size, etc). | |
1188 | */ | |
1189 | static void blkfront_connect(struct blkfront_info *info) | |
1190 | { | |
1191 | unsigned long long sectors; | |
1192 | unsigned long sector_size; | |
1193 | unsigned int binfo; | |
1194 | int err; | |
ed30bf31 | 1195 | int barrier, flush, discard; |
9f27ee59 | 1196 | |
1fa73be6 S |
1197 | switch (info->connected) { |
1198 | case BLKIF_STATE_CONNECTED: | |
1199 | /* | |
1200 | * Potentially, the back-end may be signalling | |
1201 | * a capacity change; update the capacity. | |
1202 | */ | |
1203 | err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, | |
1204 | "sectors", "%Lu", §ors); | |
1205 | if (XENBUS_EXIST_ERR(err)) | |
1206 | return; | |
1207 | printk(KERN_INFO "Setting capacity to %Lu\n", | |
1208 | sectors); | |
1209 | set_capacity(info->gd, sectors); | |
2def141e | 1210 | revalidate_disk(info->gd); |
1fa73be6 S |
1211 | |
1212 | /* fall through */ | |
1213 | case BLKIF_STATE_SUSPENDED: | |
9f27ee59 JF |
1214 | return; |
1215 | ||
b4dddb49 JF |
1216 | default: |
1217 | break; | |
1fa73be6 | 1218 | } |
9f27ee59 JF |
1219 | |
1220 | dev_dbg(&info->xbdev->dev, "%s:%s.\n", | |
1221 | __func__, info->xbdev->otherend); | |
1222 | ||
1223 | err = xenbus_gather(XBT_NIL, info->xbdev->otherend, | |
1224 | "sectors", "%llu", §ors, | |
1225 | "info", "%u", &binfo, | |
1226 | "sector-size", "%lu", §or_size, | |
1227 | NULL); | |
1228 | if (err) { | |
1229 | xenbus_dev_fatal(info->xbdev, err, | |
1230 | "reading backend fields at %s", | |
1231 | info->xbdev->otherend); | |
1232 | return; | |
1233 | } | |
1234 | ||
edf6ef59 KRW |
1235 | info->feature_flush = 0; |
1236 | info->flush_op = 0; | |
1237 | ||
9f27ee59 | 1238 | err = xenbus_gather(XBT_NIL, info->xbdev->otherend, |
4352b47a | 1239 | "feature-barrier", "%d", &barrier, |
9f27ee59 | 1240 | NULL); |
7901d141 JF |
1241 | |
1242 | /* | |
1243 | * If there's no "feature-barrier" defined, then it means | |
1244 | * we're dealing with a very old backend which writes | |
4913efe4 | 1245 | * synchronously; nothing to do. |
7901d141 | 1246 | * |
6958f145 | 1247 | * If there are barriers, then we use flush. |
7901d141 | 1248 | */ |
edf6ef59 | 1249 | if (!err && barrier) { |
be2f8373 | 1250 | info->feature_flush = REQ_FLUSH | REQ_FUA; |
edf6ef59 KRW |
1251 | info->flush_op = BLKIF_OP_WRITE_BARRIER; |
1252 | } | |
1253 | /* | |
1254 | * And if there is "feature-flush-cache" use that above | |
1255 | * barriers. | |
1256 | */ | |
1257 | err = xenbus_gather(XBT_NIL, info->xbdev->otherend, | |
1258 | "feature-flush-cache", "%d", &flush, | |
1259 | NULL); | |
9f27ee59 | 1260 | |
edf6ef59 KRW |
1261 | if (!err && flush) { |
1262 | info->feature_flush = REQ_FLUSH; | |
1263 | info->flush_op = BLKIF_OP_FLUSH_DISKCACHE; | |
1264 | } | |
ed30bf31 LD |
1265 | |
1266 | err = xenbus_gather(XBT_NIL, info->xbdev->otherend, | |
1267 | "feature-discard", "%d", &discard, | |
1268 | NULL); | |
1269 | ||
1270 | if (!err && discard) | |
1271 | blkfront_setup_discard(info); | |
1272 | ||
9246b5f0 | 1273 | err = xlvbd_alloc_gendisk(sectors, info, binfo, sector_size); |
9f27ee59 JF |
1274 | if (err) { |
1275 | xenbus_dev_fatal(info->xbdev, err, "xlvbd_add at %s", | |
1276 | info->xbdev->otherend); | |
1277 | return; | |
1278 | } | |
1279 | ||
1280 | xenbus_switch_state(info->xbdev, XenbusStateConnected); | |
1281 | ||
1282 | /* Kick pending requests. */ | |
3467811e | 1283 | spin_lock_irq(&info->io_lock); |
9f27ee59 JF |
1284 | info->connected = BLKIF_STATE_CONNECTED; |
1285 | kick_pending_request_queues(info); | |
3467811e | 1286 | spin_unlock_irq(&info->io_lock); |
9f27ee59 JF |
1287 | |
1288 | add_disk(info->gd); | |
1d78d705 CL |
1289 | |
1290 | info->is_ready = 1; | |
9f27ee59 JF |
1291 | } |
1292 | ||
9f27ee59 JF |
1293 | /** |
1294 | * Callback received when the backend's state changes. | |
1295 | */ | |
203fd61f | 1296 | static void blkback_changed(struct xenbus_device *dev, |
9f27ee59 JF |
1297 | enum xenbus_state backend_state) |
1298 | { | |
a1b4b12b | 1299 | struct blkfront_info *info = dev_get_drvdata(&dev->dev); |
9f27ee59 | 1300 | |
203fd61f | 1301 | dev_dbg(&dev->dev, "blkfront:blkback_changed to state %d.\n", backend_state); |
9f27ee59 JF |
1302 | |
1303 | switch (backend_state) { | |
1304 | case XenbusStateInitialising: | |
1305 | case XenbusStateInitWait: | |
1306 | case XenbusStateInitialised: | |
b78c9512 NI |
1307 | case XenbusStateReconfiguring: |
1308 | case XenbusStateReconfigured: | |
9f27ee59 JF |
1309 | case XenbusStateUnknown: |
1310 | case XenbusStateClosed: | |
1311 | break; | |
1312 | ||
1313 | case XenbusStateConnected: | |
1314 | blkfront_connect(info); | |
1315 | break; | |
1316 | ||
1317 | case XenbusStateClosing: | |
b70f5fa0 | 1318 | blkfront_closing(info); |
9f27ee59 JF |
1319 | break; |
1320 | } | |
1321 | } | |
1322 | ||
fa1bd359 | 1323 | static int blkfront_remove(struct xenbus_device *xbdev) |
9f27ee59 | 1324 | { |
fa1bd359 DS |
1325 | struct blkfront_info *info = dev_get_drvdata(&xbdev->dev); |
1326 | struct block_device *bdev = NULL; | |
1327 | struct gendisk *disk; | |
9f27ee59 | 1328 | |
fa1bd359 | 1329 | dev_dbg(&xbdev->dev, "%s removed", xbdev->nodename); |
9f27ee59 JF |
1330 | |
1331 | blkif_free(info, 0); | |
1332 | ||
fa1bd359 DS |
1333 | mutex_lock(&info->mutex); |
1334 | ||
1335 | disk = info->gd; | |
1336 | if (disk) | |
1337 | bdev = bdget_disk(disk, 0); | |
1338 | ||
1339 | info->xbdev = NULL; | |
1340 | mutex_unlock(&info->mutex); | |
1341 | ||
1342 | if (!bdev) { | |
1343 | kfree(info); | |
1344 | return 0; | |
1345 | } | |
1346 | ||
1347 | /* | |
1348 | * The xbdev was removed before we reached the Closed | |
1349 | * state. See if it's safe to remove the disk. If the bdev | |
1350 | * isn't closed yet, we let release take care of it. | |
1351 | */ | |
1352 | ||
1353 | mutex_lock(&bdev->bd_mutex); | |
1354 | info = disk->private_data; | |
1355 | ||
d54142c7 DS |
1356 | dev_warn(disk_to_dev(disk), |
1357 | "%s was hot-unplugged, %d stale handles\n", | |
1358 | xbdev->nodename, bdev->bd_openers); | |
1359 | ||
7b32d104 | 1360 | if (info && !bdev->bd_openers) { |
fa1bd359 DS |
1361 | xlvbd_release_gendisk(info); |
1362 | disk->private_data = NULL; | |
0e345826 | 1363 | kfree(info); |
fa1bd359 DS |
1364 | } |
1365 | ||
1366 | mutex_unlock(&bdev->bd_mutex); | |
1367 | bdput(bdev); | |
9f27ee59 JF |
1368 | |
1369 | return 0; | |
1370 | } | |
1371 | ||
1d78d705 CL |
1372 | static int blkfront_is_ready(struct xenbus_device *dev) |
1373 | { | |
a1b4b12b | 1374 | struct blkfront_info *info = dev_get_drvdata(&dev->dev); |
1d78d705 | 1375 | |
5d7ed20e | 1376 | return info->is_ready && info->xbdev; |
1d78d705 CL |
1377 | } |
1378 | ||
a63c848b | 1379 | static int blkif_open(struct block_device *bdev, fmode_t mode) |
9f27ee59 | 1380 | { |
13961743 DS |
1381 | struct gendisk *disk = bdev->bd_disk; |
1382 | struct blkfront_info *info; | |
1383 | int err = 0; | |
6e9624b8 | 1384 | |
2a48fc0a | 1385 | mutex_lock(&blkfront_mutex); |
6e9624b8 | 1386 | |
13961743 DS |
1387 | info = disk->private_data; |
1388 | if (!info) { | |
1389 | /* xbdev gone */ | |
1390 | err = -ERESTARTSYS; | |
1391 | goto out; | |
1392 | } | |
1393 | ||
1394 | mutex_lock(&info->mutex); | |
1395 | ||
1396 | if (!info->gd) | |
1397 | /* xbdev is closed */ | |
1398 | err = -ERESTARTSYS; | |
1399 | ||
1400 | mutex_unlock(&info->mutex); | |
1401 | ||
13961743 | 1402 | out: |
2a48fc0a | 1403 | mutex_unlock(&blkfront_mutex); |
13961743 | 1404 | return err; |
9f27ee59 JF |
1405 | } |
1406 | ||
a63c848b | 1407 | static int blkif_release(struct gendisk *disk, fmode_t mode) |
9f27ee59 | 1408 | { |
a63c848b | 1409 | struct blkfront_info *info = disk->private_data; |
7fd152f4 DS |
1410 | struct block_device *bdev; |
1411 | struct xenbus_device *xbdev; | |
1412 | ||
2a48fc0a | 1413 | mutex_lock(&blkfront_mutex); |
7fd152f4 DS |
1414 | |
1415 | bdev = bdget_disk(disk, 0); | |
7fd152f4 | 1416 | |
acfca3c6 DS |
1417 | if (bdev->bd_openers) |
1418 | goto out; | |
1419 | ||
7fd152f4 DS |
1420 | /* |
1421 | * Check if we have been instructed to close. We will have | |
1422 | * deferred this request, because the bdev was still open. | |
1423 | */ | |
1424 | ||
1425 | mutex_lock(&info->mutex); | |
1426 | xbdev = info->xbdev; | |
1427 | ||
1428 | if (xbdev && xbdev->state == XenbusStateClosing) { | |
1429 | /* pending switch to state closed */ | |
d54142c7 | 1430 | dev_info(disk_to_dev(bdev->bd_disk), "releasing disk\n"); |
7fd152f4 DS |
1431 | xlvbd_release_gendisk(info); |
1432 | xenbus_frontend_closed(info->xbdev); | |
1433 | } | |
1434 | ||
1435 | mutex_unlock(&info->mutex); | |
1436 | ||
1437 | if (!xbdev) { | |
1438 | /* sudden device removal */ | |
d54142c7 | 1439 | dev_info(disk_to_dev(bdev->bd_disk), "releasing disk\n"); |
7fd152f4 DS |
1440 | xlvbd_release_gendisk(info); |
1441 | disk->private_data = NULL; | |
1442 | kfree(info); | |
9f27ee59 | 1443 | } |
7fd152f4 | 1444 | |
a4cc14ec | 1445 | out: |
dad5cf65 | 1446 | bdput(bdev); |
2a48fc0a | 1447 | mutex_unlock(&blkfront_mutex); |
9f27ee59 JF |
1448 | return 0; |
1449 | } | |
1450 | ||
83d5cde4 | 1451 | static const struct block_device_operations xlvbd_block_fops = |
9f27ee59 JF |
1452 | { |
1453 | .owner = THIS_MODULE, | |
a63c848b AV |
1454 | .open = blkif_open, |
1455 | .release = blkif_release, | |
597592d9 | 1456 | .getgeo = blkif_getgeo, |
8a6cfeb6 | 1457 | .ioctl = blkif_ioctl, |
9f27ee59 JF |
1458 | }; |
1459 | ||
1460 | ||
ec9c42ec | 1461 | static const struct xenbus_device_id blkfront_ids[] = { |
9f27ee59 JF |
1462 | { "vbd" }, |
1463 | { "" } | |
1464 | }; | |
1465 | ||
73db144b | 1466 | static DEFINE_XENBUS_DRIVER(blkfront, , |
9f27ee59 JF |
1467 | .probe = blkfront_probe, |
1468 | .remove = blkfront_remove, | |
1469 | .resume = blkfront_resume, | |
203fd61f | 1470 | .otherend_changed = blkback_changed, |
1d78d705 | 1471 | .is_ready = blkfront_is_ready, |
73db144b | 1472 | ); |
9f27ee59 JF |
1473 | |
1474 | static int __init xlblk_init(void) | |
1475 | { | |
469738e6 LE |
1476 | int ret; |
1477 | ||
6e833587 | 1478 | if (!xen_domain()) |
9f27ee59 JF |
1479 | return -ENODEV; |
1480 | ||
e95ae5a4 | 1481 | if (xen_hvm_domain() && !xen_platform_pci_unplug) |
b9136d20 IM |
1482 | return -ENODEV; |
1483 | ||
9f27ee59 JF |
1484 | if (register_blkdev(XENVBD_MAJOR, DEV_NAME)) { |
1485 | printk(KERN_WARNING "xen_blk: can't get major %d with name %s\n", | |
1486 | XENVBD_MAJOR, DEV_NAME); | |
1487 | return -ENODEV; | |
1488 | } | |
1489 | ||
73db144b | 1490 | ret = xenbus_register_frontend(&blkfront_driver); |
469738e6 LE |
1491 | if (ret) { |
1492 | unregister_blkdev(XENVBD_MAJOR, DEV_NAME); | |
1493 | return ret; | |
1494 | } | |
1495 | ||
1496 | return 0; | |
9f27ee59 JF |
1497 | } |
1498 | module_init(xlblk_init); | |
1499 | ||
1500 | ||
5a60d0cd | 1501 | static void __exit xlblk_exit(void) |
9f27ee59 | 1502 | { |
73db144b | 1503 | return xenbus_unregister_driver(&blkfront_driver); |
9f27ee59 JF |
1504 | } |
1505 | module_exit(xlblk_exit); | |
1506 | ||
1507 | MODULE_DESCRIPTION("Xen virtual block device frontend"); | |
1508 | MODULE_LICENSE("GPL"); | |
1509 | MODULE_ALIAS_BLOCKDEV_MAJOR(XENVBD_MAJOR); | |
d2f0c52b | 1510 | MODULE_ALIAS("xen:vbd"); |
4f93f09b | 1511 | MODULE_ALIAS("xenblk"); |