Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Network block device - make block devices work over TCP | |
3 | * | |
4 | * Note that you can not swap over this thing, yet. Seems to work but | |
5 | * deadlocks sometimes - you can not swap over TCP in general. | |
6 | * | |
7 | * Copyright 1997-2000 Pavel Machek <pavel@ucw.cz> | |
8 | * Parts copyright 2001 Steven Whitehouse <steve@chygwyn.com> | |
9 | * | |
dbf492d6 | 10 | * This file is released under GPLv2 or later. |
1da177e4 | 11 | * |
dbf492d6 | 12 | * (part of code stolen from loop.c) |
1da177e4 LT |
13 | */ |
14 | ||
15 | #include <linux/major.h> | |
16 | ||
17 | #include <linux/blkdev.h> | |
18 | #include <linux/module.h> | |
19 | #include <linux/init.h> | |
20 | #include <linux/sched.h> | |
21 | #include <linux/fs.h> | |
22 | #include <linux/bio.h> | |
23 | #include <linux/stat.h> | |
24 | #include <linux/errno.h> | |
25 | #include <linux/file.h> | |
26 | #include <linux/ioctl.h> | |
4b2f0260 HX |
27 | #include <linux/compiler.h> |
28 | #include <linux/err.h> | |
29 | #include <linux/kernel.h> | |
1da177e4 LT |
30 | #include <net/sock.h> |
31 | ||
1da177e4 | 32 | #include <asm/uaccess.h> |
4b2f0260 | 33 | #include <asm/system.h> |
1da177e4 LT |
34 | #include <asm/types.h> |
35 | ||
36 | #include <linux/nbd.h> | |
37 | ||
38 | #define LO_MAGIC 0x68797548 | |
39 | ||
40 | #ifdef NDEBUG | |
41 | #define dprintk(flags, fmt...) | |
42 | #else /* NDEBUG */ | |
43 | #define dprintk(flags, fmt...) do { \ | |
44 | if (debugflags & (flags)) printk(KERN_DEBUG fmt); \ | |
45 | } while (0) | |
46 | #define DBG_IOCTL 0x0004 | |
47 | #define DBG_INIT 0x0010 | |
48 | #define DBG_EXIT 0x0020 | |
49 | #define DBG_BLKDEV 0x0100 | |
50 | #define DBG_RX 0x0200 | |
51 | #define DBG_TX 0x0400 | |
52 | static unsigned int debugflags; | |
53 | #endif /* NDEBUG */ | |
54 | ||
9c7a4169 | 55 | static unsigned int nbds_max = 16; |
1da177e4 LT |
56 | static struct nbd_device nbd_dev[MAX_NBD]; |
57 | ||
58 | /* | |
59 | * Use just one lock (or at most 1 per NIC). Two arguments for this: | |
60 | * 1. Each NIC is essentially a synchronization point for all servers | |
61 | * accessed through that NIC so there's no need to have more locks | |
62 | * than NICs anyway. | |
63 | * 2. More locks lead to more "Dirty cache line bouncing" which will slow | |
64 | * down each lock to the point where they're actually slower than just | |
65 | * a single lock. | |
66 | * Thanks go to Jens Axboe and Al Viro for their LKML emails explaining this! | |
67 | */ | |
68 | static DEFINE_SPINLOCK(nbd_lock); | |
69 | ||
70 | #ifndef NDEBUG | |
71 | static const char *ioctl_cmd_to_ascii(int cmd) | |
72 | { | |
73 | switch (cmd) { | |
74 | case NBD_SET_SOCK: return "set-sock"; | |
75 | case NBD_SET_BLKSIZE: return "set-blksize"; | |
76 | case NBD_SET_SIZE: return "set-size"; | |
77 | case NBD_DO_IT: return "do-it"; | |
78 | case NBD_CLEAR_SOCK: return "clear-sock"; | |
79 | case NBD_CLEAR_QUE: return "clear-que"; | |
80 | case NBD_PRINT_DEBUG: return "print-debug"; | |
81 | case NBD_SET_SIZE_BLOCKS: return "set-size-blocks"; | |
82 | case NBD_DISCONNECT: return "disconnect"; | |
83 | case BLKROSET: return "set-read-only"; | |
84 | case BLKFLSBUF: return "flush-buffer-cache"; | |
85 | } | |
86 | return "unknown"; | |
87 | } | |
88 | ||
89 | static const char *nbdcmd_to_ascii(int cmd) | |
90 | { | |
91 | switch (cmd) { | |
92 | case NBD_CMD_READ: return "read"; | |
93 | case NBD_CMD_WRITE: return "write"; | |
94 | case NBD_CMD_DISC: return "disconnect"; | |
95 | } | |
96 | return "invalid"; | |
97 | } | |
98 | #endif /* NDEBUG */ | |
99 | ||
100 | static void nbd_end_request(struct request *req) | |
101 | { | |
102 | int uptodate = (req->errors == 0) ? 1 : 0; | |
103 | request_queue_t *q = req->q; | |
104 | unsigned long flags; | |
105 | ||
106 | dprintk(DBG_BLKDEV, "%s: request %p: %s\n", req->rq_disk->disk_name, | |
107 | req, uptodate? "done": "failed"); | |
108 | ||
109 | spin_lock_irqsave(q->queue_lock, flags); | |
110 | if (!end_that_request_first(req, uptodate, req->nr_sectors)) { | |
8ffdc655 | 111 | end_that_request_last(req, uptodate); |
1da177e4 LT |
112 | } |
113 | spin_unlock_irqrestore(q->queue_lock, flags); | |
114 | } | |
115 | ||
116 | /* | |
117 | * Send or receive packet. | |
118 | */ | |
119 | static int sock_xmit(struct socket *sock, int send, void *buf, int size, | |
120 | int msg_flags) | |
121 | { | |
122 | int result; | |
123 | struct msghdr msg; | |
124 | struct kvec iov; | |
125 | unsigned long flags; | |
126 | sigset_t oldset; | |
127 | ||
128 | /* Allow interception of SIGKILL only | |
129 | * Don't allow other signals to interrupt the transmission */ | |
130 | spin_lock_irqsave(¤t->sighand->siglock, flags); | |
131 | oldset = current->blocked; | |
132 | sigfillset(¤t->blocked); | |
133 | sigdelsetmask(¤t->blocked, sigmask(SIGKILL)); | |
134 | recalc_sigpending(); | |
135 | spin_unlock_irqrestore(¤t->sighand->siglock, flags); | |
136 | ||
137 | do { | |
138 | sock->sk->sk_allocation = GFP_NOIO; | |
139 | iov.iov_base = buf; | |
140 | iov.iov_len = size; | |
141 | msg.msg_name = NULL; | |
142 | msg.msg_namelen = 0; | |
143 | msg.msg_control = NULL; | |
144 | msg.msg_controllen = 0; | |
1da177e4 LT |
145 | msg.msg_flags = msg_flags | MSG_NOSIGNAL; |
146 | ||
147 | if (send) | |
148 | result = kernel_sendmsg(sock, &msg, &iov, 1, size); | |
149 | else | |
150 | result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0); | |
151 | ||
152 | if (signal_pending(current)) { | |
153 | siginfo_t info; | |
154 | spin_lock_irqsave(¤t->sighand->siglock, flags); | |
155 | printk(KERN_WARNING "nbd (pid %d: %s) got signal %d\n", | |
156 | current->pid, current->comm, | |
157 | dequeue_signal(current, ¤t->blocked, &info)); | |
158 | spin_unlock_irqrestore(¤t->sighand->siglock, flags); | |
159 | result = -EINTR; | |
160 | break; | |
161 | } | |
162 | ||
163 | if (result <= 0) { | |
164 | if (result == 0) | |
165 | result = -EPIPE; /* short read */ | |
166 | break; | |
167 | } | |
168 | size -= result; | |
169 | buf += result; | |
170 | } while (size > 0); | |
171 | ||
172 | spin_lock_irqsave(¤t->sighand->siglock, flags); | |
173 | current->blocked = oldset; | |
174 | recalc_sigpending(); | |
175 | spin_unlock_irqrestore(¤t->sighand->siglock, flags); | |
176 | ||
177 | return result; | |
178 | } | |
179 | ||
180 | static inline int sock_send_bvec(struct socket *sock, struct bio_vec *bvec, | |
181 | int flags) | |
182 | { | |
183 | int result; | |
184 | void *kaddr = kmap(bvec->bv_page); | |
185 | result = sock_xmit(sock, 1, kaddr + bvec->bv_offset, bvec->bv_len, | |
186 | flags); | |
187 | kunmap(bvec->bv_page); | |
188 | return result; | |
189 | } | |
190 | ||
191 | static int nbd_send_req(struct nbd_device *lo, struct request *req) | |
192 | { | |
193 | int result, i, flags; | |
194 | struct nbd_request request; | |
195 | unsigned long size = req->nr_sectors << 9; | |
196 | struct socket *sock = lo->sock; | |
197 | ||
198 | request.magic = htonl(NBD_REQUEST_MAGIC); | |
199 | request.type = htonl(nbd_cmd(req)); | |
200 | request.from = cpu_to_be64((u64) req->sector << 9); | |
201 | request.len = htonl(size); | |
202 | memcpy(request.handle, &req, sizeof(req)); | |
203 | ||
1da177e4 LT |
204 | dprintk(DBG_TX, "%s: request %p: sending control (%s@%llu,%luB)\n", |
205 | lo->disk->disk_name, req, | |
206 | nbdcmd_to_ascii(nbd_cmd(req)), | |
207 | (unsigned long long)req->sector << 9, | |
208 | req->nr_sectors << 9); | |
209 | result = sock_xmit(sock, 1, &request, sizeof(request), | |
210 | (nbd_cmd(req) == NBD_CMD_WRITE)? MSG_MORE: 0); | |
211 | if (result <= 0) { | |
212 | printk(KERN_ERR "%s: Send control failed (result %d)\n", | |
213 | lo->disk->disk_name, result); | |
214 | goto error_out; | |
215 | } | |
216 | ||
217 | if (nbd_cmd(req) == NBD_CMD_WRITE) { | |
218 | struct bio *bio; | |
219 | /* | |
220 | * we are really probing at internals to determine | |
221 | * whether to set MSG_MORE or not... | |
222 | */ | |
223 | rq_for_each_bio(bio, req) { | |
224 | struct bio_vec *bvec; | |
225 | bio_for_each_segment(bvec, bio, i) { | |
226 | flags = 0; | |
227 | if ((i < (bio->bi_vcnt - 1)) || bio->bi_next) | |
228 | flags = MSG_MORE; | |
229 | dprintk(DBG_TX, "%s: request %p: sending %d bytes data\n", | |
230 | lo->disk->disk_name, req, | |
231 | bvec->bv_len); | |
232 | result = sock_send_bvec(sock, bvec, flags); | |
233 | if (result <= 0) { | |
234 | printk(KERN_ERR "%s: Send data failed (result %d)\n", | |
235 | lo->disk->disk_name, | |
236 | result); | |
237 | goto error_out; | |
238 | } | |
239 | } | |
240 | } | |
241 | } | |
1da177e4 LT |
242 | return 0; |
243 | ||
244 | error_out: | |
1da177e4 LT |
245 | return 1; |
246 | } | |
247 | ||
248 | static struct request *nbd_find_request(struct nbd_device *lo, char *handle) | |
249 | { | |
250 | struct request *req; | |
251 | struct list_head *tmp; | |
252 | struct request *xreq; | |
4b2f0260 | 253 | int err; |
1da177e4 LT |
254 | |
255 | memcpy(&xreq, handle, sizeof(xreq)); | |
256 | ||
4b2f0260 HX |
257 | err = wait_event_interruptible(lo->active_wq, lo->active_req != xreq); |
258 | if (unlikely(err)) | |
259 | goto out; | |
260 | ||
1da177e4 LT |
261 | spin_lock(&lo->queue_lock); |
262 | list_for_each(tmp, &lo->queue_head) { | |
263 | req = list_entry(tmp, struct request, queuelist); | |
264 | if (req != xreq) | |
265 | continue; | |
266 | list_del_init(&req->queuelist); | |
267 | spin_unlock(&lo->queue_lock); | |
268 | return req; | |
269 | } | |
270 | spin_unlock(&lo->queue_lock); | |
4b2f0260 HX |
271 | |
272 | err = -ENOENT; | |
273 | ||
274 | out: | |
275 | return ERR_PTR(err); | |
1da177e4 LT |
276 | } |
277 | ||
278 | static inline int sock_recv_bvec(struct socket *sock, struct bio_vec *bvec) | |
279 | { | |
280 | int result; | |
281 | void *kaddr = kmap(bvec->bv_page); | |
282 | result = sock_xmit(sock, 0, kaddr + bvec->bv_offset, bvec->bv_len, | |
283 | MSG_WAITALL); | |
284 | kunmap(bvec->bv_page); | |
285 | return result; | |
286 | } | |
287 | ||
288 | /* NULL returned = something went wrong, inform userspace */ | |
289 | static struct request *nbd_read_stat(struct nbd_device *lo) | |
290 | { | |
291 | int result; | |
292 | struct nbd_reply reply; | |
293 | struct request *req; | |
294 | struct socket *sock = lo->sock; | |
295 | ||
296 | reply.magic = 0; | |
297 | result = sock_xmit(sock, 0, &reply, sizeof(reply), MSG_WAITALL); | |
298 | if (result <= 0) { | |
299 | printk(KERN_ERR "%s: Receive control failed (result %d)\n", | |
300 | lo->disk->disk_name, result); | |
301 | goto harderror; | |
302 | } | |
e4b57e08 MF |
303 | |
304 | if (ntohl(reply.magic) != NBD_REPLY_MAGIC) { | |
305 | printk(KERN_ERR "%s: Wrong magic (0x%lx)\n", | |
306 | lo->disk->disk_name, | |
307 | (unsigned long)ntohl(reply.magic)); | |
308 | result = -EPROTO; | |
309 | goto harderror; | |
310 | } | |
311 | ||
1da177e4 | 312 | req = nbd_find_request(lo, reply.handle); |
4b2f0260 HX |
313 | if (unlikely(IS_ERR(req))) { |
314 | result = PTR_ERR(req); | |
315 | if (result != -ENOENT) | |
316 | goto harderror; | |
317 | ||
1da177e4 LT |
318 | printk(KERN_ERR "%s: Unexpected reply (%p)\n", |
319 | lo->disk->disk_name, reply.handle); | |
320 | result = -EBADR; | |
321 | goto harderror; | |
322 | } | |
323 | ||
1da177e4 LT |
324 | if (ntohl(reply.error)) { |
325 | printk(KERN_ERR "%s: Other side returned error (%d)\n", | |
326 | lo->disk->disk_name, ntohl(reply.error)); | |
327 | req->errors++; | |
328 | return req; | |
329 | } | |
330 | ||
331 | dprintk(DBG_RX, "%s: request %p: got reply\n", | |
332 | lo->disk->disk_name, req); | |
333 | if (nbd_cmd(req) == NBD_CMD_READ) { | |
334 | int i; | |
335 | struct bio *bio; | |
336 | rq_for_each_bio(bio, req) { | |
337 | struct bio_vec *bvec; | |
338 | bio_for_each_segment(bvec, bio, i) { | |
339 | result = sock_recv_bvec(sock, bvec); | |
340 | if (result <= 0) { | |
341 | printk(KERN_ERR "%s: Receive data failed (result %d)\n", | |
342 | lo->disk->disk_name, | |
343 | result); | |
f0df33bc MF |
344 | req->errors++; |
345 | return req; | |
1da177e4 LT |
346 | } |
347 | dprintk(DBG_RX, "%s: request %p: got %d bytes data\n", | |
348 | lo->disk->disk_name, req, bvec->bv_len); | |
349 | } | |
350 | } | |
351 | } | |
352 | return req; | |
353 | harderror: | |
354 | lo->harderror = result; | |
355 | return NULL; | |
356 | } | |
357 | ||
6b39bb65 PC |
358 | static ssize_t pid_show(struct gendisk *disk, char *page) |
359 | { | |
360 | return sprintf(page, "%ld\n", | |
361 | (long) ((struct nbd_device *)disk->private_data)->pid); | |
362 | } | |
363 | ||
364 | static struct disk_attribute pid_attr = { | |
365 | .attr = { .name = "pid", .mode = S_IRUGO }, | |
366 | .show = pid_show, | |
367 | }; | |
368 | ||
1da177e4 LT |
369 | static void nbd_do_it(struct nbd_device *lo) |
370 | { | |
371 | struct request *req; | |
372 | ||
373 | BUG_ON(lo->magic != LO_MAGIC); | |
374 | ||
6b39bb65 PC |
375 | lo->pid = current->pid; |
376 | sysfs_create_file(&lo->disk->kobj, &pid_attr.attr); | |
377 | ||
1da177e4 LT |
378 | while ((req = nbd_read_stat(lo)) != NULL) |
379 | nbd_end_request(req); | |
6b39bb65 PC |
380 | |
381 | sysfs_remove_file(&lo->disk->kobj, &pid_attr.attr); | |
1da177e4 LT |
382 | return; |
383 | } | |
384 | ||
385 | static void nbd_clear_que(struct nbd_device *lo) | |
386 | { | |
387 | struct request *req; | |
388 | ||
389 | BUG_ON(lo->magic != LO_MAGIC); | |
390 | ||
4b2f0260 HX |
391 | /* |
392 | * Because we have set lo->sock to NULL under the tx_lock, all | |
393 | * modifications to the list must have completed by now. For | |
394 | * the same reason, the active_req must be NULL. | |
395 | * | |
396 | * As a consequence, we don't need to take the spin lock while | |
397 | * purging the list here. | |
398 | */ | |
399 | BUG_ON(lo->sock); | |
400 | BUG_ON(lo->active_req); | |
401 | ||
402 | while (!list_empty(&lo->queue_head)) { | |
403 | req = list_entry(lo->queue_head.next, struct request, | |
404 | queuelist); | |
405 | list_del_init(&req->queuelist); | |
406 | req->errors++; | |
407 | nbd_end_request(req); | |
408 | } | |
1da177e4 LT |
409 | } |
410 | ||
411 | /* | |
412 | * We always wait for result of write, for now. It would be nice to make it optional | |
413 | * in future | |
414 | * if ((req->cmd == WRITE) && (lo->flags & NBD_WRITE_NOCHK)) | |
415 | * { printk( "Warning: Ignoring result!\n"); nbd_end_request( req ); } | |
416 | */ | |
417 | ||
418 | static void do_nbd_request(request_queue_t * q) | |
419 | { | |
420 | struct request *req; | |
421 | ||
422 | while ((req = elv_next_request(q)) != NULL) { | |
423 | struct nbd_device *lo; | |
424 | ||
425 | blkdev_dequeue_request(req); | |
4aff5e23 JA |
426 | dprintk(DBG_BLKDEV, "%s: request %p: dequeued (flags=%x)\n", |
427 | req->rq_disk->disk_name, req, req->cmd_type); | |
1da177e4 | 428 | |
4aff5e23 | 429 | if (!blk_fs_request(req)) |
1da177e4 LT |
430 | goto error_out; |
431 | ||
432 | lo = req->rq_disk->private_data; | |
433 | ||
434 | BUG_ON(lo->magic != LO_MAGIC); | |
435 | ||
1da177e4 LT |
436 | nbd_cmd(req) = NBD_CMD_READ; |
437 | if (rq_data_dir(req) == WRITE) { | |
438 | nbd_cmd(req) = NBD_CMD_WRITE; | |
439 | if (lo->flags & NBD_READ_ONLY) { | |
440 | printk(KERN_ERR "%s: Write on read-only\n", | |
441 | lo->disk->disk_name); | |
442 | goto error_out; | |
443 | } | |
444 | } | |
445 | ||
446 | req->errors = 0; | |
447 | spin_unlock_irq(q->queue_lock); | |
448 | ||
82d4dc5a | 449 | mutex_lock(&lo->tx_lock); |
4b2f0260 | 450 | if (unlikely(!lo->sock)) { |
82d4dc5a | 451 | mutex_unlock(&lo->tx_lock); |
4b2f0260 HX |
452 | printk(KERN_ERR "%s: Attempted send on closed socket\n", |
453 | lo->disk->disk_name); | |
1da177e4 LT |
454 | req->errors++; |
455 | nbd_end_request(req); | |
456 | spin_lock_irq(q->queue_lock); | |
457 | continue; | |
458 | } | |
459 | ||
4b2f0260 | 460 | lo->active_req = req; |
1da177e4 LT |
461 | |
462 | if (nbd_send_req(lo, req) != 0) { | |
463 | printk(KERN_ERR "%s: Request send failed\n", | |
464 | lo->disk->disk_name); | |
4b2f0260 HX |
465 | req->errors++; |
466 | nbd_end_request(req); | |
467 | } else { | |
468 | spin_lock(&lo->queue_lock); | |
469 | list_add(&req->queuelist, &lo->queue_head); | |
470 | spin_unlock(&lo->queue_lock); | |
1da177e4 LT |
471 | } |
472 | ||
4b2f0260 | 473 | lo->active_req = NULL; |
82d4dc5a | 474 | mutex_unlock(&lo->tx_lock); |
4b2f0260 HX |
475 | wake_up_all(&lo->active_wq); |
476 | ||
1da177e4 LT |
477 | spin_lock_irq(q->queue_lock); |
478 | continue; | |
479 | ||
480 | error_out: | |
481 | req->errors++; | |
482 | spin_unlock(q->queue_lock); | |
483 | nbd_end_request(req); | |
484 | spin_lock(q->queue_lock); | |
485 | } | |
486 | return; | |
487 | } | |
488 | ||
489 | static int nbd_ioctl(struct inode *inode, struct file *file, | |
490 | unsigned int cmd, unsigned long arg) | |
491 | { | |
492 | struct nbd_device *lo = inode->i_bdev->bd_disk->private_data; | |
493 | int error; | |
494 | struct request sreq ; | |
495 | ||
496 | if (!capable(CAP_SYS_ADMIN)) | |
497 | return -EPERM; | |
498 | ||
499 | BUG_ON(lo->magic != LO_MAGIC); | |
500 | ||
501 | /* Anyone capable of this syscall can do *real bad* things */ | |
502 | dprintk(DBG_IOCTL, "%s: nbd_ioctl cmd=%s(0x%x) arg=%lu\n", | |
503 | lo->disk->disk_name, ioctl_cmd_to_ascii(cmd), cmd, arg); | |
504 | ||
505 | switch (cmd) { | |
506 | case NBD_DISCONNECT: | |
507 | printk(KERN_INFO "%s: NBD_DISCONNECT\n", lo->disk->disk_name); | |
4aff5e23 | 508 | sreq.cmd_type = REQ_TYPE_SPECIAL; |
1da177e4 LT |
509 | nbd_cmd(&sreq) = NBD_CMD_DISC; |
510 | /* | |
511 | * Set these to sane values in case server implementation | |
512 | * fails to check the request type first and also to keep | |
513 | * debugging output cleaner. | |
514 | */ | |
515 | sreq.sector = 0; | |
516 | sreq.nr_sectors = 0; | |
517 | if (!lo->sock) | |
518 | return -EINVAL; | |
519 | nbd_send_req(lo, &sreq); | |
520 | return 0; | |
521 | ||
522 | case NBD_CLEAR_SOCK: | |
523 | error = 0; | |
82d4dc5a | 524 | mutex_lock(&lo->tx_lock); |
1da177e4 | 525 | lo->sock = NULL; |
82d4dc5a | 526 | mutex_unlock(&lo->tx_lock); |
1da177e4 LT |
527 | file = lo->file; |
528 | lo->file = NULL; | |
1da177e4 | 529 | nbd_clear_que(lo); |
4b2f0260 | 530 | BUG_ON(!list_empty(&lo->queue_head)); |
1da177e4 LT |
531 | if (file) |
532 | fput(file); | |
533 | return error; | |
534 | case NBD_SET_SOCK: | |
535 | if (lo->file) | |
536 | return -EBUSY; | |
537 | error = -EINVAL; | |
538 | file = fget(arg); | |
539 | if (file) { | |
17506041 | 540 | inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
541 | if (S_ISSOCK(inode->i_mode)) { |
542 | lo->file = file; | |
543 | lo->sock = SOCKET_I(inode); | |
544 | error = 0; | |
545 | } else { | |
546 | fput(file); | |
547 | } | |
548 | } | |
549 | return error; | |
550 | case NBD_SET_BLKSIZE: | |
551 | lo->blksize = arg; | |
552 | lo->bytesize &= ~(lo->blksize-1); | |
553 | inode->i_bdev->bd_inode->i_size = lo->bytesize; | |
554 | set_blocksize(inode->i_bdev, lo->blksize); | |
555 | set_capacity(lo->disk, lo->bytesize >> 9); | |
556 | return 0; | |
557 | case NBD_SET_SIZE: | |
558 | lo->bytesize = arg & ~(lo->blksize-1); | |
559 | inode->i_bdev->bd_inode->i_size = lo->bytesize; | |
560 | set_blocksize(inode->i_bdev, lo->blksize); | |
561 | set_capacity(lo->disk, lo->bytesize >> 9); | |
562 | return 0; | |
563 | case NBD_SET_SIZE_BLOCKS: | |
564 | lo->bytesize = ((u64) arg) * lo->blksize; | |
565 | inode->i_bdev->bd_inode->i_size = lo->bytesize; | |
566 | set_blocksize(inode->i_bdev, lo->blksize); | |
567 | set_capacity(lo->disk, lo->bytesize >> 9); | |
568 | return 0; | |
569 | case NBD_DO_IT: | |
570 | if (!lo->file) | |
571 | return -EINVAL; | |
572 | nbd_do_it(lo); | |
573 | /* on return tidy up in case we have a signal */ | |
574 | /* Forcibly shutdown the socket causing all listeners | |
575 | * to error | |
576 | * | |
577 | * FIXME: This code is duplicated from sys_shutdown, but | |
578 | * there should be a more generic interface rather than | |
579 | * calling socket ops directly here */ | |
82d4dc5a | 580 | mutex_lock(&lo->tx_lock); |
1da177e4 LT |
581 | if (lo->sock) { |
582 | printk(KERN_WARNING "%s: shutting down socket\n", | |
583 | lo->disk->disk_name); | |
584 | lo->sock->ops->shutdown(lo->sock, | |
585 | SEND_SHUTDOWN|RCV_SHUTDOWN); | |
586 | lo->sock = NULL; | |
587 | } | |
82d4dc5a | 588 | mutex_unlock(&lo->tx_lock); |
1da177e4 LT |
589 | file = lo->file; |
590 | lo->file = NULL; | |
1da177e4 LT |
591 | nbd_clear_que(lo); |
592 | printk(KERN_WARNING "%s: queue cleared\n", lo->disk->disk_name); | |
593 | if (file) | |
594 | fput(file); | |
595 | return lo->harderror; | |
596 | case NBD_CLEAR_QUE: | |
4b2f0260 HX |
597 | /* |
598 | * This is for compatibility only. The queue is always cleared | |
599 | * by NBD_DO_IT or NBD_CLEAR_SOCK. | |
600 | */ | |
601 | BUG_ON(!lo->sock && !list_empty(&lo->queue_head)); | |
1da177e4 LT |
602 | return 0; |
603 | case NBD_PRINT_DEBUG: | |
604 | printk(KERN_INFO "%s: next = %p, prev = %p, head = %p\n", | |
605 | inode->i_bdev->bd_disk->disk_name, | |
606 | lo->queue_head.next, lo->queue_head.prev, | |
607 | &lo->queue_head); | |
608 | return 0; | |
609 | } | |
610 | return -EINVAL; | |
611 | } | |
612 | ||
613 | static struct block_device_operations nbd_fops = | |
614 | { | |
615 | .owner = THIS_MODULE, | |
616 | .ioctl = nbd_ioctl, | |
617 | }; | |
618 | ||
619 | /* | |
620 | * And here should be modules and kernel interface | |
621 | * (Just smiley confuses emacs :-) | |
622 | */ | |
623 | ||
624 | static int __init nbd_init(void) | |
625 | { | |
626 | int err = -ENOMEM; | |
627 | int i; | |
628 | ||
5b7b18cc | 629 | BUILD_BUG_ON(sizeof(struct nbd_request) != 28); |
1da177e4 | 630 | |
40be0c28 LMB |
631 | if (nbds_max > MAX_NBD) { |
632 | printk(KERN_CRIT "nbd: cannot allocate more than %u nbds; %u requested.\n", MAX_NBD, | |
633 | nbds_max); | |
634 | return -EINVAL; | |
635 | } | |
636 | ||
637 | for (i = 0; i < nbds_max; i++) { | |
1da177e4 LT |
638 | struct gendisk *disk = alloc_disk(1); |
639 | if (!disk) | |
640 | goto out; | |
641 | nbd_dev[i].disk = disk; | |
642 | /* | |
643 | * The new linux 2.5 block layer implementation requires | |
644 | * every gendisk to have its very own request_queue struct. | |
645 | * These structs are big so we dynamically allocate them. | |
646 | */ | |
647 | disk->queue = blk_init_queue(do_nbd_request, &nbd_lock); | |
648 | if (!disk->queue) { | |
649 | put_disk(disk); | |
650 | goto out; | |
651 | } | |
652 | } | |
653 | ||
654 | if (register_blkdev(NBD_MAJOR, "nbd")) { | |
655 | err = -EIO; | |
656 | goto out; | |
657 | } | |
658 | ||
659 | printk(KERN_INFO "nbd: registered device at major %d\n", NBD_MAJOR); | |
660 | dprintk(DBG_INIT, "nbd: debugflags=0x%x\n", debugflags); | |
661 | ||
40be0c28 | 662 | for (i = 0; i < nbds_max; i++) { |
1da177e4 LT |
663 | struct gendisk *disk = nbd_dev[i].disk; |
664 | nbd_dev[i].file = NULL; | |
665 | nbd_dev[i].magic = LO_MAGIC; | |
666 | nbd_dev[i].flags = 0; | |
667 | spin_lock_init(&nbd_dev[i].queue_lock); | |
668 | INIT_LIST_HEAD(&nbd_dev[i].queue_head); | |
82d4dc5a | 669 | mutex_init(&nbd_dev[i].tx_lock); |
4b2f0260 | 670 | init_waitqueue_head(&nbd_dev[i].active_wq); |
1da177e4 LT |
671 | nbd_dev[i].blksize = 1024; |
672 | nbd_dev[i].bytesize = 0x7ffffc00ULL << 10; /* 2TB */ | |
673 | disk->major = NBD_MAJOR; | |
674 | disk->first_minor = i; | |
675 | disk->fops = &nbd_fops; | |
676 | disk->private_data = &nbd_dev[i]; | |
677 | disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO; | |
678 | sprintf(disk->disk_name, "nbd%d", i); | |
1da177e4 LT |
679 | set_capacity(disk, 0x7ffffc00ULL << 1); /* 2 TB */ |
680 | add_disk(disk); | |
681 | } | |
682 | ||
683 | return 0; | |
684 | out: | |
685 | while (i--) { | |
686 | blk_cleanup_queue(nbd_dev[i].disk->queue); | |
687 | put_disk(nbd_dev[i].disk); | |
688 | } | |
689 | return err; | |
690 | } | |
691 | ||
692 | static void __exit nbd_cleanup(void) | |
693 | { | |
694 | int i; | |
40be0c28 | 695 | for (i = 0; i < nbds_max; i++) { |
1da177e4 | 696 | struct gendisk *disk = nbd_dev[i].disk; |
40be0c28 | 697 | nbd_dev[i].magic = 0; |
1da177e4 LT |
698 | if (disk) { |
699 | del_gendisk(disk); | |
700 | blk_cleanup_queue(disk->queue); | |
701 | put_disk(disk); | |
702 | } | |
703 | } | |
1da177e4 LT |
704 | unregister_blkdev(NBD_MAJOR, "nbd"); |
705 | printk(KERN_INFO "nbd: unregistered device at major %d\n", NBD_MAJOR); | |
706 | } | |
707 | ||
708 | module_init(nbd_init); | |
709 | module_exit(nbd_cleanup); | |
710 | ||
711 | MODULE_DESCRIPTION("Network Block Device"); | |
712 | MODULE_LICENSE("GPL"); | |
713 | ||
40be0c28 LMB |
714 | module_param(nbds_max, int, 0444); |
715 | MODULE_PARM_DESC(nbds_max, "How many network block devices to initialize."); | |
1da177e4 LT |
716 | #ifndef NDEBUG |
717 | module_param(debugflags, int, 0644); | |
718 | MODULE_PARM_DESC(debugflags, "flags for controlling debug output"); | |
719 | #endif |