1 | /* |
2 | * Copyright (c) 2006,2007 The Regents of the University of Michigan. |
3 | * All rights reserved. |
4 | * |
5 | * Andy Adamson <andros@citi.umich.edu> |
6 | * Fred Isaman <iisaman@umich.edu> |
7 | * |
8 | * permission is granted to use, copy, create derivative works and |
9 | * redistribute this software and such derivative works for any purpose, |
10 | * so long as the name of the university of michigan is not used in |
11 | * any advertising or publicity pertaining to the use or distribution |
12 | * of this software without specific, written prior authorization. if |
13 | * the above copyright notice or any other identification of the |
14 | * university of michigan is included in any copy of any portion of |
15 | * this software, then the disclaimer below must also be included. |
16 | * |
17 | * this software is provided as is, without representation from the |
18 | * university of michigan as to its fitness for any purpose, and without |
19 | * warranty by the university of michigan of any kind, either express |
20 | * or implied, including without limitation the implied warranties of |
21 | * merchantability and fitness for a particular purpose. the regents |
22 | * of the university of michigan shall not be liable for any damages, |
23 | * including special, indirect, incidental, or consequential damages, |
24 | * with respect to any claim arising out or in connection with the use |
25 | * of the software, even if it has been or is hereafter advised of the |
26 | * possibility of such damages. |
27 | */ |
28 | |
29 | #include <linux/module.h> |
30 | #include <linux/blkdev.h> |
31 | |
32 | #include "blocklayout.h" |
33 | |
34 | #define NFSDBG_FACILITY NFSDBG_PNFS_LD |
35 | |
36 | static void |
37 | nfs4_encode_simple(__be32 *p, struct pnfs_block_volume *b) |
38 | { |
39 | int i; |
40 | |
41 | *p++ = cpu_to_be32(1); |
42 | *p++ = cpu_to_be32(b->type); |
43 | *p++ = cpu_to_be32(b->simple.nr_sigs); |
44 | for (i = 0; i < b->simple.nr_sigs; i++) { |
45 | p = xdr_encode_hyper(p, val: b->simple.sigs[i].offset); |
46 | p = xdr_encode_opaque(p, ptr: b->simple.sigs[i].sig, |
47 | len: b->simple.sigs[i].sig_len); |
48 | } |
49 | } |
50 | |
51 | dev_t |
52 | bl_resolve_deviceid(struct nfs_server *server, struct pnfs_block_volume *b, |
53 | gfp_t gfp_mask) |
54 | { |
55 | struct net *net = server->nfs_client->cl_net; |
56 | struct nfs_net *nn = net_generic(net, id: nfs_net_id); |
57 | struct bl_dev_msg *reply = &nn->bl_mount_reply; |
58 | struct bl_pipe_msg bl_pipe_msg; |
59 | struct rpc_pipe_msg *msg = &bl_pipe_msg.msg; |
60 | struct bl_msg_hdr *bl_msg; |
61 | DECLARE_WAITQUEUE(wq, current); |
62 | dev_t dev = 0; |
63 | int rc; |
64 | |
65 | dprintk("%s CREATING PIPEFS MESSAGE\n" , __func__); |
66 | |
67 | mutex_lock(&nn->bl_mutex); |
68 | bl_pipe_msg.bl_wq = &nn->bl_wq; |
69 | |
70 | b->simple.len += 4; /* single volume */ |
71 | if (b->simple.len > PAGE_SIZE) |
72 | goto out_unlock; |
73 | |
74 | memset(msg, 0, sizeof(*msg)); |
75 | msg->len = sizeof(*bl_msg) + b->simple.len; |
76 | msg->data = kzalloc(size: msg->len, flags: gfp_mask); |
77 | if (!msg->data) |
78 | goto out_unlock; |
79 | |
80 | bl_msg = msg->data; |
81 | bl_msg->type = BL_DEVICE_MOUNT; |
82 | bl_msg->totallen = b->simple.len; |
83 | nfs4_encode_simple(p: msg->data + sizeof(*bl_msg), b); |
84 | |
85 | dprintk("%s CALLING USERSPACE DAEMON\n" , __func__); |
86 | add_wait_queue(wq_head: &nn->bl_wq, wq_entry: &wq); |
87 | rc = rpc_queue_upcall(nn->bl_device_pipe, msg); |
88 | if (rc < 0) { |
89 | remove_wait_queue(wq_head: &nn->bl_wq, wq_entry: &wq); |
90 | goto out_free_data; |
91 | } |
92 | |
93 | set_current_state(TASK_UNINTERRUPTIBLE); |
94 | schedule(); |
95 | remove_wait_queue(wq_head: &nn->bl_wq, wq_entry: &wq); |
96 | |
97 | if (reply->status != BL_DEVICE_REQUEST_PROC) { |
98 | printk(KERN_WARNING "%s failed to decode device: %d\n" , |
99 | __func__, reply->status); |
100 | goto out_free_data; |
101 | } |
102 | |
103 | dev = MKDEV(reply->major, reply->minor); |
104 | out_free_data: |
105 | kfree(objp: msg->data); |
106 | out_unlock: |
107 | mutex_unlock(lock: &nn->bl_mutex); |
108 | return dev; |
109 | } |
110 | |
111 | static ssize_t bl_pipe_downcall(struct file *filp, const char __user *src, |
112 | size_t mlen) |
113 | { |
114 | struct nfs_net *nn = net_generic(net: file_inode(f: filp)->i_sb->s_fs_info, |
115 | id: nfs_net_id); |
116 | |
117 | if (mlen != sizeof (struct bl_dev_msg)) |
118 | return -EINVAL; |
119 | |
120 | if (copy_from_user(to: &nn->bl_mount_reply, from: src, n: mlen) != 0) |
121 | return -EFAULT; |
122 | |
123 | wake_up(&nn->bl_wq); |
124 | |
125 | return mlen; |
126 | } |
127 | |
128 | static void bl_pipe_destroy_msg(struct rpc_pipe_msg *msg) |
129 | { |
130 | struct bl_pipe_msg *bl_pipe_msg = |
131 | container_of(msg, struct bl_pipe_msg, msg); |
132 | |
133 | if (msg->errno >= 0) |
134 | return; |
135 | wake_up(bl_pipe_msg->bl_wq); |
136 | } |
137 | |
138 | static const struct rpc_pipe_ops bl_upcall_ops = { |
139 | .upcall = rpc_pipe_generic_upcall, |
140 | .downcall = bl_pipe_downcall, |
141 | .destroy_msg = bl_pipe_destroy_msg, |
142 | }; |
143 | |
144 | static struct dentry *nfs4blocklayout_register_sb(struct super_block *sb, |
145 | struct rpc_pipe *pipe) |
146 | { |
147 | struct dentry *dir, *dentry; |
148 | |
149 | dir = rpc_d_lookup_sb(sb, NFS_PIPE_DIRNAME); |
150 | if (dir == NULL) |
151 | return ERR_PTR(error: -ENOENT); |
152 | dentry = rpc_mkpipe_dentry(dir, "blocklayout" , NULL, pipe); |
153 | dput(dir); |
154 | return dentry; |
155 | } |
156 | |
157 | static void nfs4blocklayout_unregister_sb(struct super_block *sb, |
158 | struct rpc_pipe *pipe) |
159 | { |
160 | if (pipe->dentry) |
161 | rpc_unlink(pipe->dentry); |
162 | } |
163 | |
164 | static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, |
165 | void *ptr) |
166 | { |
167 | struct super_block *sb = ptr; |
168 | struct net *net = sb->s_fs_info; |
169 | struct nfs_net *nn = net_generic(net, id: nfs_net_id); |
170 | struct dentry *dentry; |
171 | int ret = 0; |
172 | |
173 | if (!try_module_get(THIS_MODULE)) |
174 | return 0; |
175 | |
176 | if (nn->bl_device_pipe == NULL) { |
177 | module_put(THIS_MODULE); |
178 | return 0; |
179 | } |
180 | |
181 | switch (event) { |
182 | case RPC_PIPEFS_MOUNT: |
183 | dentry = nfs4blocklayout_register_sb(sb, pipe: nn->bl_device_pipe); |
184 | if (IS_ERR(ptr: dentry)) { |
185 | ret = PTR_ERR(ptr: dentry); |
186 | break; |
187 | } |
188 | nn->bl_device_pipe->dentry = dentry; |
189 | break; |
190 | case RPC_PIPEFS_UMOUNT: |
191 | if (nn->bl_device_pipe->dentry) |
192 | nfs4blocklayout_unregister_sb(sb, pipe: nn->bl_device_pipe); |
193 | break; |
194 | default: |
195 | ret = -ENOTSUPP; |
196 | break; |
197 | } |
198 | module_put(THIS_MODULE); |
199 | return ret; |
200 | } |
201 | |
202 | static struct notifier_block nfs4blocklayout_block = { |
203 | .notifier_call = rpc_pipefs_event, |
204 | }; |
205 | |
206 | static struct dentry *nfs4blocklayout_register_net(struct net *net, |
207 | struct rpc_pipe *pipe) |
208 | { |
209 | struct super_block *pipefs_sb; |
210 | struct dentry *dentry; |
211 | |
212 | pipefs_sb = rpc_get_sb_net(net); |
213 | if (!pipefs_sb) |
214 | return NULL; |
215 | dentry = nfs4blocklayout_register_sb(sb: pipefs_sb, pipe); |
216 | rpc_put_sb_net(net); |
217 | return dentry; |
218 | } |
219 | |
220 | static void nfs4blocklayout_unregister_net(struct net *net, |
221 | struct rpc_pipe *pipe) |
222 | { |
223 | struct super_block *pipefs_sb; |
224 | |
225 | pipefs_sb = rpc_get_sb_net(net); |
226 | if (pipefs_sb) { |
227 | nfs4blocklayout_unregister_sb(sb: pipefs_sb, pipe); |
228 | rpc_put_sb_net(net); |
229 | } |
230 | } |
231 | |
232 | static int nfs4blocklayout_net_init(struct net *net) |
233 | { |
234 | struct nfs_net *nn = net_generic(net, id: nfs_net_id); |
235 | struct dentry *dentry; |
236 | |
237 | mutex_init(&nn->bl_mutex); |
238 | init_waitqueue_head(&nn->bl_wq); |
239 | nn->bl_device_pipe = rpc_mkpipe_data(ops: &bl_upcall_ops, flags: 0); |
240 | if (IS_ERR(ptr: nn->bl_device_pipe)) |
241 | return PTR_ERR(ptr: nn->bl_device_pipe); |
242 | dentry = nfs4blocklayout_register_net(net, pipe: nn->bl_device_pipe); |
243 | if (IS_ERR(ptr: dentry)) { |
244 | rpc_destroy_pipe_data(pipe: nn->bl_device_pipe); |
245 | return PTR_ERR(ptr: dentry); |
246 | } |
247 | nn->bl_device_pipe->dentry = dentry; |
248 | return 0; |
249 | } |
250 | |
251 | static void nfs4blocklayout_net_exit(struct net *net) |
252 | { |
253 | struct nfs_net *nn = net_generic(net, id: nfs_net_id); |
254 | |
255 | nfs4blocklayout_unregister_net(net, pipe: nn->bl_device_pipe); |
256 | rpc_destroy_pipe_data(pipe: nn->bl_device_pipe); |
257 | nn->bl_device_pipe = NULL; |
258 | } |
259 | |
260 | static struct pernet_operations nfs4blocklayout_net_ops = { |
261 | .init = nfs4blocklayout_net_init, |
262 | .exit = nfs4blocklayout_net_exit, |
263 | }; |
264 | |
265 | int __init bl_init_pipefs(void) |
266 | { |
267 | int ret; |
268 | |
269 | ret = rpc_pipefs_notifier_register(&nfs4blocklayout_block); |
270 | if (ret) |
271 | goto out; |
272 | ret = register_pernet_subsys(&nfs4blocklayout_net_ops); |
273 | if (ret) |
274 | goto out_unregister_notifier; |
275 | return 0; |
276 | |
277 | out_unregister_notifier: |
278 | rpc_pipefs_notifier_unregister(&nfs4blocklayout_block); |
279 | out: |
280 | return ret; |
281 | } |
282 | |
283 | void bl_cleanup_pipefs(void) |
284 | { |
285 | rpc_pipefs_notifier_unregister(&nfs4blocklayout_block); |
286 | unregister_pernet_subsys(&nfs4blocklayout_net_ops); |
287 | } |
288 | |