Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | * |
Pavel Machek | dbf492d | 2006-06-25 05:47:42 -0700 | [diff] [blame] | 10 | * This file is released under GPLv2 or later. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | * |
Pavel Machek | dbf492d | 2006-06-25 05:47:42 -0700 | [diff] [blame] | 12 | * (part of code stolen from loop.c) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 27 | #include <linux/compiler.h> |
| 28 | #include <linux/err.h> |
| 29 | #include <linux/kernel.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <net/sock.h> |
Trond Myklebust | 91cf45f | 2007-11-12 18:10:39 -0800 | [diff] [blame] | 31 | #include <linux/net.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | #include <asm/uaccess.h> |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 34 | #include <asm/system.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | #include <asm/types.h> |
| 36 | |
| 37 | #include <linux/nbd.h> |
| 38 | |
| 39 | #define LO_MAGIC 0x68797548 |
| 40 | |
| 41 | #ifdef NDEBUG |
| 42 | #define dprintk(flags, fmt...) |
| 43 | #else /* NDEBUG */ |
| 44 | #define dprintk(flags, fmt...) do { \ |
| 45 | if (debugflags & (flags)) printk(KERN_DEBUG fmt); \ |
| 46 | } while (0) |
| 47 | #define DBG_IOCTL 0x0004 |
| 48 | #define DBG_INIT 0x0010 |
| 49 | #define DBG_EXIT 0x0020 |
| 50 | #define DBG_BLKDEV 0x0100 |
| 51 | #define DBG_RX 0x0200 |
| 52 | #define DBG_TX 0x0400 |
| 53 | static unsigned int debugflags; |
| 54 | #endif /* NDEBUG */ |
| 55 | |
Ingo van Lil | 9c7a416 | 2006-07-01 04:36:36 -0700 | [diff] [blame] | 56 | static unsigned int nbds_max = 16; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | static struct nbd_device nbd_dev[MAX_NBD]; |
| 58 | |
| 59 | /* |
| 60 | * Use just one lock (or at most 1 per NIC). Two arguments for this: |
| 61 | * 1. Each NIC is essentially a synchronization point for all servers |
| 62 | * accessed through that NIC so there's no need to have more locks |
| 63 | * than NICs anyway. |
| 64 | * 2. More locks lead to more "Dirty cache line bouncing" which will slow |
| 65 | * down each lock to the point where they're actually slower than just |
| 66 | * a single lock. |
| 67 | * Thanks go to Jens Axboe and Al Viro for their LKML emails explaining this! |
| 68 | */ |
| 69 | static DEFINE_SPINLOCK(nbd_lock); |
| 70 | |
| 71 | #ifndef NDEBUG |
| 72 | static const char *ioctl_cmd_to_ascii(int cmd) |
| 73 | { |
| 74 | switch (cmd) { |
| 75 | case NBD_SET_SOCK: return "set-sock"; |
| 76 | case NBD_SET_BLKSIZE: return "set-blksize"; |
| 77 | case NBD_SET_SIZE: return "set-size"; |
| 78 | case NBD_DO_IT: return "do-it"; |
| 79 | case NBD_CLEAR_SOCK: return "clear-sock"; |
| 80 | case NBD_CLEAR_QUE: return "clear-que"; |
| 81 | case NBD_PRINT_DEBUG: return "print-debug"; |
| 82 | case NBD_SET_SIZE_BLOCKS: return "set-size-blocks"; |
| 83 | case NBD_DISCONNECT: return "disconnect"; |
| 84 | case BLKROSET: return "set-read-only"; |
| 85 | case BLKFLSBUF: return "flush-buffer-cache"; |
| 86 | } |
| 87 | return "unknown"; |
| 88 | } |
| 89 | |
| 90 | static const char *nbdcmd_to_ascii(int cmd) |
| 91 | { |
| 92 | switch (cmd) { |
| 93 | case NBD_CMD_READ: return "read"; |
| 94 | case NBD_CMD_WRITE: return "write"; |
| 95 | case NBD_CMD_DISC: return "disconnect"; |
| 96 | } |
| 97 | return "invalid"; |
| 98 | } |
| 99 | #endif /* NDEBUG */ |
| 100 | |
| 101 | static void nbd_end_request(struct request *req) |
| 102 | { |
| 103 | int uptodate = (req->errors == 0) ? 1 : 0; |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 104 | struct request_queue *q = req->q; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | unsigned long flags; |
| 106 | |
| 107 | dprintk(DBG_BLKDEV, "%s: request %p: %s\n", req->rq_disk->disk_name, |
| 108 | req, uptodate? "done": "failed"); |
| 109 | |
| 110 | spin_lock_irqsave(q->queue_lock, flags); |
| 111 | if (!end_that_request_first(req, uptodate, req->nr_sectors)) { |
Tejun Heo | 8ffdc65 | 2006-01-06 09:49:03 +0100 | [diff] [blame] | 112 | end_that_request_last(req, uptodate); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | } |
| 114 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 115 | } |
| 116 | |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 117 | static void sock_shutdown(struct nbd_device *lo, int lock) |
| 118 | { |
| 119 | /* Forcibly shutdown the socket causing all listeners |
| 120 | * to error |
| 121 | * |
| 122 | * FIXME: This code is duplicated from sys_shutdown, but |
| 123 | * there should be a more generic interface rather than |
| 124 | * calling socket ops directly here */ |
| 125 | if (lock) |
| 126 | mutex_lock(&lo->tx_lock); |
| 127 | if (lo->sock) { |
| 128 | printk(KERN_WARNING "%s: shutting down socket\n", |
| 129 | lo->disk->disk_name); |
Trond Myklebust | 91cf45f | 2007-11-12 18:10:39 -0800 | [diff] [blame] | 130 | kernel_sock_shutdown(lo->sock, SHUT_RDWR); |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 131 | lo->sock = NULL; |
| 132 | } |
| 133 | if (lock) |
| 134 | mutex_unlock(&lo->tx_lock); |
| 135 | } |
| 136 | |
| 137 | static void nbd_xmit_timeout(unsigned long arg) |
| 138 | { |
| 139 | struct task_struct *task = (struct task_struct *)arg; |
| 140 | |
| 141 | printk(KERN_WARNING "nbd: killing hung xmit (%s, pid: %d)\n", |
| 142 | task->comm, task->pid); |
| 143 | force_sig(SIGKILL, task); |
| 144 | } |
| 145 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | /* |
| 147 | * Send or receive packet. |
| 148 | */ |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 149 | static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | int msg_flags) |
| 151 | { |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 152 | struct socket *sock = lo->sock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | int result; |
| 154 | struct msghdr msg; |
| 155 | struct kvec iov; |
Oleg Nesterov | be0ef95 | 2007-07-15 23:41:32 -0700 | [diff] [blame] | 156 | sigset_t blocked, oldset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | |
| 158 | /* Allow interception of SIGKILL only |
| 159 | * Don't allow other signals to interrupt the transmission */ |
Oleg Nesterov | be0ef95 | 2007-07-15 23:41:32 -0700 | [diff] [blame] | 160 | siginitsetinv(&blocked, sigmask(SIGKILL)); |
| 161 | sigprocmask(SIG_SETMASK, &blocked, &oldset); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | |
| 163 | do { |
| 164 | sock->sk->sk_allocation = GFP_NOIO; |
| 165 | iov.iov_base = buf; |
| 166 | iov.iov_len = size; |
| 167 | msg.msg_name = NULL; |
| 168 | msg.msg_namelen = 0; |
| 169 | msg.msg_control = NULL; |
| 170 | msg.msg_controllen = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | msg.msg_flags = msg_flags | MSG_NOSIGNAL; |
| 172 | |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 173 | if (send) { |
| 174 | struct timer_list ti; |
| 175 | |
| 176 | if (lo->xmit_timeout) { |
| 177 | init_timer(&ti); |
| 178 | ti.function = nbd_xmit_timeout; |
| 179 | ti.data = (unsigned long)current; |
| 180 | ti.expires = jiffies + lo->xmit_timeout; |
| 181 | add_timer(&ti); |
| 182 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | result = kernel_sendmsg(sock, &msg, &iov, 1, size); |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 184 | if (lo->xmit_timeout) |
| 185 | del_timer_sync(&ti); |
| 186 | } else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0); |
| 188 | |
| 189 | if (signal_pending(current)) { |
| 190 | siginfo_t info; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | printk(KERN_WARNING "nbd (pid %d: %s) got signal %d\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 192 | task_pid_nr(current), current->comm, |
Oleg Nesterov | be0ef95 | 2007-07-15 23:41:32 -0700 | [diff] [blame] | 193 | dequeue_signal_lock(current, ¤t->blocked, &info)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | result = -EINTR; |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 195 | sock_shutdown(lo, !send); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | break; |
| 197 | } |
| 198 | |
| 199 | if (result <= 0) { |
| 200 | if (result == 0) |
| 201 | result = -EPIPE; /* short read */ |
| 202 | break; |
| 203 | } |
| 204 | size -= result; |
| 205 | buf += result; |
| 206 | } while (size > 0); |
| 207 | |
Oleg Nesterov | be0ef95 | 2007-07-15 23:41:32 -0700 | [diff] [blame] | 208 | sigprocmask(SIG_SETMASK, &oldset, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | |
| 210 | return result; |
| 211 | } |
| 212 | |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 213 | static inline int sock_send_bvec(struct nbd_device *lo, struct bio_vec *bvec, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | int flags) |
| 215 | { |
| 216 | int result; |
| 217 | void *kaddr = kmap(bvec->bv_page); |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 218 | result = sock_xmit(lo, 1, kaddr + bvec->bv_offset, bvec->bv_len, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | kunmap(bvec->bv_page); |
| 220 | return result; |
| 221 | } |
| 222 | |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 223 | /* always call with the tx_lock held */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | static int nbd_send_req(struct nbd_device *lo, struct request *req) |
| 225 | { |
NeilBrown | 5705f70 | 2007-09-25 12:35:59 +0200 | [diff] [blame] | 226 | int result, flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | struct nbd_request request; |
| 228 | unsigned long size = req->nr_sectors << 9; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | |
| 230 | request.magic = htonl(NBD_REQUEST_MAGIC); |
| 231 | request.type = htonl(nbd_cmd(req)); |
| 232 | request.from = cpu_to_be64((u64) req->sector << 9); |
| 233 | request.len = htonl(size); |
| 234 | memcpy(request.handle, &req, sizeof(req)); |
| 235 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | dprintk(DBG_TX, "%s: request %p: sending control (%s@%llu,%luB)\n", |
| 237 | lo->disk->disk_name, req, |
| 238 | nbdcmd_to_ascii(nbd_cmd(req)), |
| 239 | (unsigned long long)req->sector << 9, |
| 240 | req->nr_sectors << 9); |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 241 | result = sock_xmit(lo, 1, &request, sizeof(request), |
| 242 | (nbd_cmd(req) == NBD_CMD_WRITE) ? MSG_MORE : 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 243 | if (result <= 0) { |
| 244 | printk(KERN_ERR "%s: Send control failed (result %d)\n", |
| 245 | lo->disk->disk_name, result); |
| 246 | goto error_out; |
| 247 | } |
| 248 | |
| 249 | if (nbd_cmd(req) == NBD_CMD_WRITE) { |
NeilBrown | 5705f70 | 2007-09-25 12:35:59 +0200 | [diff] [blame] | 250 | struct req_iterator iter; |
| 251 | struct bio_vec *bvec; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | /* |
| 253 | * we are really probing at internals to determine |
| 254 | * whether to set MSG_MORE or not... |
| 255 | */ |
NeilBrown | 5705f70 | 2007-09-25 12:35:59 +0200 | [diff] [blame] | 256 | rq_for_each_segment(bvec, req, iter) { |
Jens Axboe | 6c92e69 | 2007-08-16 13:43:12 +0200 | [diff] [blame] | 257 | flags = 0; |
| 258 | if (!rq_iter_last(req, iter)) |
| 259 | flags = MSG_MORE; |
| 260 | dprintk(DBG_TX, "%s: request %p: sending %d bytes data\n", |
| 261 | lo->disk->disk_name, req, bvec->bv_len); |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 262 | result = sock_send_bvec(lo, bvec, flags); |
Jens Axboe | 6c92e69 | 2007-08-16 13:43:12 +0200 | [diff] [blame] | 263 | if (result <= 0) { |
| 264 | printk(KERN_ERR "%s: Send data failed (result %d)\n", |
| 265 | lo->disk->disk_name, result); |
| 266 | goto error_out; |
| 267 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | } |
| 269 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | return 0; |
| 271 | |
| 272 | error_out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | return 1; |
| 274 | } |
| 275 | |
Denis Cheng | 0cbc591b | 2007-10-16 23:26:14 -0700 | [diff] [blame] | 276 | static struct request *nbd_find_request(struct nbd_device *lo, |
| 277 | struct request *xreq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | { |
Denis Cheng | d2c9740 | 2007-10-16 23:26:14 -0700 | [diff] [blame] | 279 | struct request *req, *tmp; |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 280 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 282 | err = wait_event_interruptible(lo->active_wq, lo->active_req != xreq); |
| 283 | if (unlikely(err)) |
| 284 | goto out; |
| 285 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | spin_lock(&lo->queue_lock); |
Denis Cheng | d2c9740 | 2007-10-16 23:26:14 -0700 | [diff] [blame] | 287 | list_for_each_entry_safe(req, tmp, &lo->queue_head, queuelist) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | if (req != xreq) |
| 289 | continue; |
| 290 | list_del_init(&req->queuelist); |
| 291 | spin_unlock(&lo->queue_lock); |
| 292 | return req; |
| 293 | } |
| 294 | spin_unlock(&lo->queue_lock); |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 295 | |
| 296 | err = -ENOENT; |
| 297 | |
| 298 | out: |
| 299 | return ERR_PTR(err); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | } |
| 301 | |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 302 | static inline int sock_recv_bvec(struct nbd_device *lo, struct bio_vec *bvec) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | { |
| 304 | int result; |
| 305 | void *kaddr = kmap(bvec->bv_page); |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 306 | result = sock_xmit(lo, 0, kaddr + bvec->bv_offset, bvec->bv_len, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | MSG_WAITALL); |
| 308 | kunmap(bvec->bv_page); |
| 309 | return result; |
| 310 | } |
| 311 | |
| 312 | /* NULL returned = something went wrong, inform userspace */ |
| 313 | static struct request *nbd_read_stat(struct nbd_device *lo) |
| 314 | { |
| 315 | int result; |
| 316 | struct nbd_reply reply; |
| 317 | struct request *req; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | |
| 319 | reply.magic = 0; |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 320 | result = sock_xmit(lo, 0, &reply, sizeof(reply), MSG_WAITALL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | if (result <= 0) { |
| 322 | printk(KERN_ERR "%s: Receive control failed (result %d)\n", |
| 323 | lo->disk->disk_name, result); |
| 324 | goto harderror; |
| 325 | } |
Michal Feix | e4b57e0 | 2006-07-30 03:03:31 -0700 | [diff] [blame] | 326 | |
| 327 | if (ntohl(reply.magic) != NBD_REPLY_MAGIC) { |
| 328 | printk(KERN_ERR "%s: Wrong magic (0x%lx)\n", |
| 329 | lo->disk->disk_name, |
| 330 | (unsigned long)ntohl(reply.magic)); |
| 331 | result = -EPROTO; |
| 332 | goto harderror; |
| 333 | } |
| 334 | |
Denis Cheng | 0cbc591b | 2007-10-16 23:26:14 -0700 | [diff] [blame] | 335 | req = nbd_find_request(lo, *(struct request **)reply.handle); |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 336 | if (unlikely(IS_ERR(req))) { |
| 337 | result = PTR_ERR(req); |
| 338 | if (result != -ENOENT) |
| 339 | goto harderror; |
| 340 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | printk(KERN_ERR "%s: Unexpected reply (%p)\n", |
| 342 | lo->disk->disk_name, reply.handle); |
| 343 | result = -EBADR; |
| 344 | goto harderror; |
| 345 | } |
| 346 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | if (ntohl(reply.error)) { |
| 348 | printk(KERN_ERR "%s: Other side returned error (%d)\n", |
| 349 | lo->disk->disk_name, ntohl(reply.error)); |
| 350 | req->errors++; |
| 351 | return req; |
| 352 | } |
| 353 | |
| 354 | dprintk(DBG_RX, "%s: request %p: got reply\n", |
| 355 | lo->disk->disk_name, req); |
| 356 | if (nbd_cmd(req) == NBD_CMD_READ) { |
NeilBrown | 5705f70 | 2007-09-25 12:35:59 +0200 | [diff] [blame] | 357 | struct req_iterator iter; |
| 358 | struct bio_vec *bvec; |
| 359 | |
| 360 | rq_for_each_segment(bvec, req, iter) { |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 361 | result = sock_recv_bvec(lo, bvec); |
Jens Axboe | 6c92e69 | 2007-08-16 13:43:12 +0200 | [diff] [blame] | 362 | if (result <= 0) { |
| 363 | printk(KERN_ERR "%s: Receive data failed (result %d)\n", |
| 364 | lo->disk->disk_name, result); |
| 365 | req->errors++; |
| 366 | return req; |
| 367 | } |
| 368 | dprintk(DBG_RX, "%s: request %p: got %d bytes data\n", |
| 369 | lo->disk->disk_name, req, bvec->bv_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 370 | } |
| 371 | } |
| 372 | return req; |
| 373 | harderror: |
| 374 | lo->harderror = result; |
| 375 | return NULL; |
| 376 | } |
| 377 | |
Kay Sievers | edfaa7c | 2007-05-21 22:08:01 +0200 | [diff] [blame] | 378 | static ssize_t pid_show(struct device *dev, |
| 379 | struct device_attribute *attr, char *buf) |
Paul Clements | 6b39bb6 | 2006-12-06 20:40:53 -0800 | [diff] [blame] | 380 | { |
Kay Sievers | edfaa7c | 2007-05-21 22:08:01 +0200 | [diff] [blame] | 381 | struct gendisk *disk = dev_to_disk(dev); |
| 382 | |
| 383 | return sprintf(buf, "%ld\n", |
Paul Clements | 6b39bb6 | 2006-12-06 20:40:53 -0800 | [diff] [blame] | 384 | (long) ((struct nbd_device *)disk->private_data)->pid); |
| 385 | } |
| 386 | |
Kay Sievers | edfaa7c | 2007-05-21 22:08:01 +0200 | [diff] [blame] | 387 | static struct device_attribute pid_attr = { |
| 388 | .attr = { .name = "pid", .mode = S_IRUGO, .owner = THIS_MODULE }, |
Paul Clements | 6b39bb6 | 2006-12-06 20:40:53 -0800 | [diff] [blame] | 389 | .show = pid_show, |
| 390 | }; |
| 391 | |
WANG Cong | 8496304 | 2007-05-09 02:33:36 -0700 | [diff] [blame] | 392 | static int nbd_do_it(struct nbd_device *lo) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | { |
| 394 | struct request *req; |
WANG Cong | 8496304 | 2007-05-09 02:33:36 -0700 | [diff] [blame] | 395 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | |
| 397 | BUG_ON(lo->magic != LO_MAGIC); |
| 398 | |
Paul Clements | 6b39bb6 | 2006-12-06 20:40:53 -0800 | [diff] [blame] | 399 | lo->pid = current->pid; |
Kay Sievers | edfaa7c | 2007-05-21 22:08:01 +0200 | [diff] [blame] | 400 | ret = sysfs_create_file(&lo->disk->dev.kobj, &pid_attr.attr); |
WANG Cong | 8496304 | 2007-05-09 02:33:36 -0700 | [diff] [blame] | 401 | if (ret) { |
| 402 | printk(KERN_ERR "nbd: sysfs_create_file failed!"); |
| 403 | return ret; |
| 404 | } |
Paul Clements | 6b39bb6 | 2006-12-06 20:40:53 -0800 | [diff] [blame] | 405 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | while ((req = nbd_read_stat(lo)) != NULL) |
| 407 | nbd_end_request(req); |
Paul Clements | 6b39bb6 | 2006-12-06 20:40:53 -0800 | [diff] [blame] | 408 | |
Kay Sievers | edfaa7c | 2007-05-21 22:08:01 +0200 | [diff] [blame] | 409 | sysfs_remove_file(&lo->disk->dev.kobj, &pid_attr.attr); |
WANG Cong | 8496304 | 2007-05-09 02:33:36 -0700 | [diff] [blame] | 410 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 411 | } |
| 412 | |
| 413 | static void nbd_clear_que(struct nbd_device *lo) |
| 414 | { |
| 415 | struct request *req; |
| 416 | |
| 417 | BUG_ON(lo->magic != LO_MAGIC); |
| 418 | |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 419 | /* |
| 420 | * Because we have set lo->sock to NULL under the tx_lock, all |
| 421 | * modifications to the list must have completed by now. For |
| 422 | * the same reason, the active_req must be NULL. |
| 423 | * |
| 424 | * As a consequence, we don't need to take the spin lock while |
| 425 | * purging the list here. |
| 426 | */ |
| 427 | BUG_ON(lo->sock); |
| 428 | BUG_ON(lo->active_req); |
| 429 | |
| 430 | while (!list_empty(&lo->queue_head)) { |
| 431 | req = list_entry(lo->queue_head.next, struct request, |
| 432 | queuelist); |
| 433 | list_del_init(&req->queuelist); |
| 434 | req->errors++; |
| 435 | nbd_end_request(req); |
| 436 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | } |
| 438 | |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 439 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | /* |
| 441 | * We always wait for result of write, for now. It would be nice to make it optional |
| 442 | * in future |
Boaz Harrosh | e654bc4 | 2007-06-20 13:53:23 +0200 | [diff] [blame] | 443 | * if ((rq_data_dir(req) == WRITE) && (lo->flags & NBD_WRITE_NOCHK)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 444 | * { printk( "Warning: Ignoring result!\n"); nbd_end_request( req ); } |
| 445 | */ |
| 446 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 447 | static void do_nbd_request(struct request_queue * q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | { |
| 449 | struct request *req; |
| 450 | |
| 451 | while ((req = elv_next_request(q)) != NULL) { |
| 452 | struct nbd_device *lo; |
| 453 | |
| 454 | blkdev_dequeue_request(req); |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 455 | dprintk(DBG_BLKDEV, "%s: request %p: dequeued (flags=%x)\n", |
| 456 | req->rq_disk->disk_name, req, req->cmd_type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 458 | if (!blk_fs_request(req)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 459 | goto error_out; |
| 460 | |
| 461 | lo = req->rq_disk->private_data; |
| 462 | |
| 463 | BUG_ON(lo->magic != LO_MAGIC); |
| 464 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | nbd_cmd(req) = NBD_CMD_READ; |
| 466 | if (rq_data_dir(req) == WRITE) { |
| 467 | nbd_cmd(req) = NBD_CMD_WRITE; |
| 468 | if (lo->flags & NBD_READ_ONLY) { |
| 469 | printk(KERN_ERR "%s: Write on read-only\n", |
| 470 | lo->disk->disk_name); |
| 471 | goto error_out; |
| 472 | } |
| 473 | } |
| 474 | |
| 475 | req->errors = 0; |
| 476 | spin_unlock_irq(q->queue_lock); |
| 477 | |
Ingo Molnar | 82d4dc5 | 2006-03-23 03:00:38 -0800 | [diff] [blame] | 478 | mutex_lock(&lo->tx_lock); |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 479 | if (unlikely(!lo->sock)) { |
Ingo Molnar | 82d4dc5 | 2006-03-23 03:00:38 -0800 | [diff] [blame] | 480 | mutex_unlock(&lo->tx_lock); |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 481 | printk(KERN_ERR "%s: Attempted send on closed socket\n", |
| 482 | lo->disk->disk_name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | req->errors++; |
| 484 | nbd_end_request(req); |
| 485 | spin_lock_irq(q->queue_lock); |
| 486 | continue; |
| 487 | } |
| 488 | |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 489 | lo->active_req = req; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 490 | |
| 491 | if (nbd_send_req(lo, req) != 0) { |
| 492 | printk(KERN_ERR "%s: Request send failed\n", |
| 493 | lo->disk->disk_name); |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 494 | req->errors++; |
| 495 | nbd_end_request(req); |
| 496 | } else { |
| 497 | spin_lock(&lo->queue_lock); |
| 498 | list_add(&req->queuelist, &lo->queue_head); |
| 499 | spin_unlock(&lo->queue_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | } |
| 501 | |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 502 | lo->active_req = NULL; |
Ingo Molnar | 82d4dc5 | 2006-03-23 03:00:38 -0800 | [diff] [blame] | 503 | mutex_unlock(&lo->tx_lock); |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 504 | wake_up_all(&lo->active_wq); |
| 505 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | spin_lock_irq(q->queue_lock); |
| 507 | continue; |
| 508 | |
| 509 | error_out: |
| 510 | req->errors++; |
| 511 | spin_unlock(q->queue_lock); |
| 512 | nbd_end_request(req); |
| 513 | spin_lock(q->queue_lock); |
| 514 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | } |
| 516 | |
| 517 | static int nbd_ioctl(struct inode *inode, struct file *file, |
| 518 | unsigned int cmd, unsigned long arg) |
| 519 | { |
| 520 | struct nbd_device *lo = inode->i_bdev->bd_disk->private_data; |
| 521 | int error; |
| 522 | struct request sreq ; |
| 523 | |
| 524 | if (!capable(CAP_SYS_ADMIN)) |
| 525 | return -EPERM; |
| 526 | |
| 527 | BUG_ON(lo->magic != LO_MAGIC); |
| 528 | |
| 529 | /* Anyone capable of this syscall can do *real bad* things */ |
| 530 | dprintk(DBG_IOCTL, "%s: nbd_ioctl cmd=%s(0x%x) arg=%lu\n", |
| 531 | lo->disk->disk_name, ioctl_cmd_to_ascii(cmd), cmd, arg); |
| 532 | |
| 533 | switch (cmd) { |
| 534 | case NBD_DISCONNECT: |
| 535 | printk(KERN_INFO "%s: NBD_DISCONNECT\n", lo->disk->disk_name); |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 536 | sreq.cmd_type = REQ_TYPE_SPECIAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | nbd_cmd(&sreq) = NBD_CMD_DISC; |
| 538 | /* |
| 539 | * Set these to sane values in case server implementation |
| 540 | * fails to check the request type first and also to keep |
| 541 | * debugging output cleaner. |
| 542 | */ |
| 543 | sreq.sector = 0; |
| 544 | sreq.nr_sectors = 0; |
| 545 | if (!lo->sock) |
| 546 | return -EINVAL; |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 547 | mutex_lock(&lo->tx_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 548 | nbd_send_req(lo, &sreq); |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 549 | mutex_unlock(&lo->tx_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 550 | return 0; |
| 551 | |
| 552 | case NBD_CLEAR_SOCK: |
| 553 | error = 0; |
Ingo Molnar | 82d4dc5 | 2006-03-23 03:00:38 -0800 | [diff] [blame] | 554 | mutex_lock(&lo->tx_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 555 | lo->sock = NULL; |
Ingo Molnar | 82d4dc5 | 2006-03-23 03:00:38 -0800 | [diff] [blame] | 556 | mutex_unlock(&lo->tx_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | file = lo->file; |
| 558 | lo->file = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 559 | nbd_clear_que(lo); |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 560 | BUG_ON(!list_empty(&lo->queue_head)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 561 | if (file) |
| 562 | fput(file); |
| 563 | return error; |
| 564 | case NBD_SET_SOCK: |
| 565 | if (lo->file) |
| 566 | return -EBUSY; |
| 567 | error = -EINVAL; |
| 568 | file = fget(arg); |
| 569 | if (file) { |
Josef Sipek | 1750604 | 2006-12-08 02:37:22 -0800 | [diff] [blame] | 570 | inode = file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 571 | if (S_ISSOCK(inode->i_mode)) { |
| 572 | lo->file = file; |
| 573 | lo->sock = SOCKET_I(inode); |
| 574 | error = 0; |
| 575 | } else { |
| 576 | fput(file); |
| 577 | } |
| 578 | } |
| 579 | return error; |
| 580 | case NBD_SET_BLKSIZE: |
| 581 | lo->blksize = arg; |
| 582 | lo->bytesize &= ~(lo->blksize-1); |
| 583 | inode->i_bdev->bd_inode->i_size = lo->bytesize; |
| 584 | set_blocksize(inode->i_bdev, lo->blksize); |
| 585 | set_capacity(lo->disk, lo->bytesize >> 9); |
| 586 | return 0; |
| 587 | case NBD_SET_SIZE: |
| 588 | lo->bytesize = arg & ~(lo->blksize-1); |
| 589 | inode->i_bdev->bd_inode->i_size = lo->bytesize; |
| 590 | set_blocksize(inode->i_bdev, lo->blksize); |
| 591 | set_capacity(lo->disk, lo->bytesize >> 9); |
| 592 | return 0; |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 593 | case NBD_SET_TIMEOUT: |
| 594 | lo->xmit_timeout = arg * HZ; |
| 595 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 596 | case NBD_SET_SIZE_BLOCKS: |
| 597 | lo->bytesize = ((u64) arg) * lo->blksize; |
| 598 | inode->i_bdev->bd_inode->i_size = lo->bytesize; |
| 599 | set_blocksize(inode->i_bdev, lo->blksize); |
| 600 | set_capacity(lo->disk, lo->bytesize >> 9); |
| 601 | return 0; |
| 602 | case NBD_DO_IT: |
| 603 | if (!lo->file) |
| 604 | return -EINVAL; |
WANG Cong | 8496304 | 2007-05-09 02:33:36 -0700 | [diff] [blame] | 605 | error = nbd_do_it(lo); |
| 606 | if (error) |
| 607 | return error; |
Paul Clements | 7fdfd40 | 2007-10-16 23:27:37 -0700 | [diff] [blame] | 608 | sock_shutdown(lo, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | file = lo->file; |
| 610 | lo->file = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | nbd_clear_que(lo); |
| 612 | printk(KERN_WARNING "%s: queue cleared\n", lo->disk->disk_name); |
| 613 | if (file) |
| 614 | fput(file); |
Paul Clements | 4b86a87 | 2007-10-16 23:27:36 -0700 | [diff] [blame] | 615 | lo->bytesize = 0; |
| 616 | inode->i_bdev->bd_inode->i_size = 0; |
| 617 | set_capacity(lo->disk, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 618 | return lo->harderror; |
| 619 | case NBD_CLEAR_QUE: |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 620 | /* |
| 621 | * This is for compatibility only. The queue is always cleared |
| 622 | * by NBD_DO_IT or NBD_CLEAR_SOCK. |
| 623 | */ |
| 624 | BUG_ON(!lo->sock && !list_empty(&lo->queue_head)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | return 0; |
| 626 | case NBD_PRINT_DEBUG: |
| 627 | printk(KERN_INFO "%s: next = %p, prev = %p, head = %p\n", |
| 628 | inode->i_bdev->bd_disk->disk_name, |
| 629 | lo->queue_head.next, lo->queue_head.prev, |
| 630 | &lo->queue_head); |
| 631 | return 0; |
| 632 | } |
| 633 | return -EINVAL; |
| 634 | } |
| 635 | |
| 636 | static struct block_device_operations nbd_fops = |
| 637 | { |
| 638 | .owner = THIS_MODULE, |
| 639 | .ioctl = nbd_ioctl, |
| 640 | }; |
| 641 | |
| 642 | /* |
| 643 | * And here should be modules and kernel interface |
| 644 | * (Just smiley confuses emacs :-) |
| 645 | */ |
| 646 | |
| 647 | static int __init nbd_init(void) |
| 648 | { |
| 649 | int err = -ENOMEM; |
| 650 | int i; |
| 651 | |
Adrian Bunk | 5b7b18c | 2006-03-25 03:07:04 -0800 | [diff] [blame] | 652 | BUILD_BUG_ON(sizeof(struct nbd_request) != 28); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 653 | |
Lars Marowsky-Bree | 40be0c2 | 2005-05-01 08:59:07 -0700 | [diff] [blame] | 654 | if (nbds_max > MAX_NBD) { |
| 655 | printk(KERN_CRIT "nbd: cannot allocate more than %u nbds; %u requested.\n", MAX_NBD, |
| 656 | nbds_max); |
| 657 | return -EINVAL; |
| 658 | } |
| 659 | |
| 660 | for (i = 0; i < nbds_max; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 661 | struct gendisk *disk = alloc_disk(1); |
| 662 | if (!disk) |
| 663 | goto out; |
| 664 | nbd_dev[i].disk = disk; |
| 665 | /* |
| 666 | * The new linux 2.5 block layer implementation requires |
| 667 | * every gendisk to have its very own request_queue struct. |
| 668 | * These structs are big so we dynamically allocate them. |
| 669 | */ |
| 670 | disk->queue = blk_init_queue(do_nbd_request, &nbd_lock); |
| 671 | if (!disk->queue) { |
| 672 | put_disk(disk); |
| 673 | goto out; |
| 674 | } |
| 675 | } |
| 676 | |
| 677 | if (register_blkdev(NBD_MAJOR, "nbd")) { |
| 678 | err = -EIO; |
| 679 | goto out; |
| 680 | } |
| 681 | |
| 682 | printk(KERN_INFO "nbd: registered device at major %d\n", NBD_MAJOR); |
| 683 | dprintk(DBG_INIT, "nbd: debugflags=0x%x\n", debugflags); |
| 684 | |
Lars Marowsky-Bree | 40be0c2 | 2005-05-01 08:59:07 -0700 | [diff] [blame] | 685 | for (i = 0; i < nbds_max; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | struct gendisk *disk = nbd_dev[i].disk; |
| 687 | nbd_dev[i].file = NULL; |
| 688 | nbd_dev[i].magic = LO_MAGIC; |
| 689 | nbd_dev[i].flags = 0; |
| 690 | spin_lock_init(&nbd_dev[i].queue_lock); |
| 691 | INIT_LIST_HEAD(&nbd_dev[i].queue_head); |
Ingo Molnar | 82d4dc5 | 2006-03-23 03:00:38 -0800 | [diff] [blame] | 692 | mutex_init(&nbd_dev[i].tx_lock); |
Herbert Xu | 4b2f026 | 2006-01-06 00:09:47 -0800 | [diff] [blame] | 693 | init_waitqueue_head(&nbd_dev[i].active_wq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 694 | nbd_dev[i].blksize = 1024; |
Paul Clements | 4b86a87 | 2007-10-16 23:27:36 -0700 | [diff] [blame] | 695 | nbd_dev[i].bytesize = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | disk->major = NBD_MAJOR; |
| 697 | disk->first_minor = i; |
| 698 | disk->fops = &nbd_fops; |
| 699 | disk->private_data = &nbd_dev[i]; |
| 700 | disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO; |
| 701 | sprintf(disk->disk_name, "nbd%d", i); |
Paul Clements | 4b86a87 | 2007-10-16 23:27:36 -0700 | [diff] [blame] | 702 | set_capacity(disk, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | add_disk(disk); |
| 704 | } |
| 705 | |
| 706 | return 0; |
| 707 | out: |
| 708 | while (i--) { |
| 709 | blk_cleanup_queue(nbd_dev[i].disk->queue); |
| 710 | put_disk(nbd_dev[i].disk); |
| 711 | } |
| 712 | return err; |
| 713 | } |
| 714 | |
| 715 | static void __exit nbd_cleanup(void) |
| 716 | { |
| 717 | int i; |
Lars Marowsky-Bree | 40be0c2 | 2005-05-01 08:59:07 -0700 | [diff] [blame] | 718 | for (i = 0; i < nbds_max; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 719 | struct gendisk *disk = nbd_dev[i].disk; |
Lars Marowsky-Bree | 40be0c2 | 2005-05-01 08:59:07 -0700 | [diff] [blame] | 720 | nbd_dev[i].magic = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | if (disk) { |
| 722 | del_gendisk(disk); |
| 723 | blk_cleanup_queue(disk->queue); |
| 724 | put_disk(disk); |
| 725 | } |
| 726 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | unregister_blkdev(NBD_MAJOR, "nbd"); |
| 728 | printk(KERN_INFO "nbd: unregistered device at major %d\n", NBD_MAJOR); |
| 729 | } |
| 730 | |
| 731 | module_init(nbd_init); |
| 732 | module_exit(nbd_cleanup); |
| 733 | |
| 734 | MODULE_DESCRIPTION("Network Block Device"); |
| 735 | MODULE_LICENSE("GPL"); |
| 736 | |
Lars Marowsky-Bree | 40be0c2 | 2005-05-01 08:59:07 -0700 | [diff] [blame] | 737 | module_param(nbds_max, int, 0444); |
| 738 | MODULE_PARM_DESC(nbds_max, "How many network block devices to initialize."); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 739 | #ifndef NDEBUG |
| 740 | module_param(debugflags, int, 0644); |
| 741 | MODULE_PARM_DESC(debugflags, "flags for controlling debug output"); |
| 742 | #endif |