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29#include <linux/module.h>
30#include <linux/genhd.h>
31#include <linux/blkdev.h>
32
33#include "blocklayout.h"
34
35#define NFSDBG_FACILITY NFSDBG_PNFS_LD
36
37static void
38nfs4_encode_simple(__be32 *p, struct pnfs_block_volume *b)
39{
40 int i;
41
42 *p++ = cpu_to_be32(1);
43 *p++ = cpu_to_be32(b->type);
44 *p++ = cpu_to_be32(b->simple.nr_sigs);
45 for (i = 0; i < b->simple.nr_sigs; i++) {
46 p = xdr_encode_hyper(p, b->simple.sigs[i].offset);
47 p = xdr_encode_opaque(p, b->simple.sigs[i].sig,
48 b->simple.sigs[i].sig_len);
49 }
50}
51
52dev_t
53bl_resolve_deviceid(struct nfs_server *server, struct pnfs_block_volume *b,
54 gfp_t gfp_mask)
55{
56 struct net *net = server->nfs_client->cl_net;
57 struct nfs_net *nn = net_generic(net, nfs_net_id);
58 struct bl_dev_msg *reply = &nn->bl_mount_reply;
59 struct bl_pipe_msg bl_pipe_msg;
60 struct rpc_pipe_msg *msg = &bl_pipe_msg.msg;
61 struct bl_msg_hdr *bl_msg;
62 DECLARE_WAITQUEUE(wq, current);
63 dev_t dev = 0;
64 int rc;
65
66 dprintk("%s CREATING PIPEFS MESSAGE\n", __func__);
67
68 mutex_lock(&nn->bl_mutex);
69 bl_pipe_msg.bl_wq = &nn->bl_wq;
70
71 b->simple.len += 4;
72 if (b->simple.len > PAGE_SIZE)
73 goto out_unlock;
74
75 memset(msg, 0, sizeof(*msg));
76 msg->len = sizeof(*bl_msg) + b->simple.len;
77 msg->data = kzalloc(msg->len, gfp_mask);
78 if (!msg->data)
79 goto out_free_data;
80
81 bl_msg = msg->data;
82 bl_msg->type = BL_DEVICE_MOUNT;
83 bl_msg->totallen = b->simple.len;
84 nfs4_encode_simple(msg->data + sizeof(*bl_msg), b);
85
86 dprintk("%s CALLING USERSPACE DAEMON\n", __func__);
87 add_wait_queue(&nn->bl_wq, &wq);
88 rc = rpc_queue_upcall(nn->bl_device_pipe, msg);
89 if (rc < 0) {
90 remove_wait_queue(&nn->bl_wq, &wq);
91 goto out_free_data;
92 }
93
94 set_current_state(TASK_UNINTERRUPTIBLE);
95 schedule();
96 remove_wait_queue(&nn->bl_wq, &wq);
97
98 if (reply->status != BL_DEVICE_REQUEST_PROC) {
99 printk(KERN_WARNING "%s failed to decode device: %d\n",
100 __func__, reply->status);
101 goto out_free_data;
102 }
103
104 dev = MKDEV(reply->major, reply->minor);
105out_free_data:
106 kfree(msg->data);
107out_unlock:
108 mutex_unlock(&nn->bl_mutex);
109 return dev;
110}
111
112static ssize_t bl_pipe_downcall(struct file *filp, const char __user *src,
113 size_t mlen)
114{
115 struct nfs_net *nn = net_generic(file_inode(filp)->i_sb->s_fs_info,
116 nfs_net_id);
117
118 if (mlen != sizeof (struct bl_dev_msg))
119 return -EINVAL;
120
121 if (copy_from_user(&nn->bl_mount_reply, src, mlen) != 0)
122 return -EFAULT;
123
124 wake_up(&nn->bl_wq);
125
126 return mlen;
127}
128
129static void bl_pipe_destroy_msg(struct rpc_pipe_msg *msg)
130{
131 struct bl_pipe_msg *bl_pipe_msg =
132 container_of(msg, struct bl_pipe_msg, msg);
133
134 if (msg->errno >= 0)
135 return;
136 wake_up(bl_pipe_msg->bl_wq);
137}
138
139static const struct rpc_pipe_ops bl_upcall_ops = {
140 .upcall = rpc_pipe_generic_upcall,
141 .downcall = bl_pipe_downcall,
142 .destroy_msg = bl_pipe_destroy_msg,
143};
144
145static struct dentry *nfs4blocklayout_register_sb(struct super_block *sb,
146 struct rpc_pipe *pipe)
147{
148 struct dentry *dir, *dentry;
149
150 dir = rpc_d_lookup_sb(sb, NFS_PIPE_DIRNAME);
151 if (dir == NULL)
152 return ERR_PTR(-ENOENT);
153 dentry = rpc_mkpipe_dentry(dir, "blocklayout", NULL, pipe);
154 dput(dir);
155 return dentry;
156}
157
158static void nfs4blocklayout_unregister_sb(struct super_block *sb,
159 struct rpc_pipe *pipe)
160{
161 if (pipe->dentry)
162 rpc_unlink(pipe->dentry);
163}
164
165static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
166 void *ptr)
167{
168 struct super_block *sb = ptr;
169 struct net *net = sb->s_fs_info;
170 struct nfs_net *nn = net_generic(net, nfs_net_id);
171 struct dentry *dentry;
172 int ret = 0;
173
174 if (!try_module_get(THIS_MODULE))
175 return 0;
176
177 if (nn->bl_device_pipe == NULL) {
178 module_put(THIS_MODULE);
179 return 0;
180 }
181
182 switch (event) {
183 case RPC_PIPEFS_MOUNT:
184 dentry = nfs4blocklayout_register_sb(sb, nn->bl_device_pipe);
185 if (IS_ERR(dentry)) {
186 ret = PTR_ERR(dentry);
187 break;
188 }
189 nn->bl_device_pipe->dentry = dentry;
190 break;
191 case RPC_PIPEFS_UMOUNT:
192 if (nn->bl_device_pipe->dentry)
193 nfs4blocklayout_unregister_sb(sb, nn->bl_device_pipe);
194 break;
195 default:
196 ret = -ENOTSUPP;
197 break;
198 }
199 module_put(THIS_MODULE);
200 return ret;
201}
202
203static struct notifier_block nfs4blocklayout_block = {
204 .notifier_call = rpc_pipefs_event,
205};
206
207static struct dentry *nfs4blocklayout_register_net(struct net *net,
208 struct rpc_pipe *pipe)
209{
210 struct super_block *pipefs_sb;
211 struct dentry *dentry;
212
213 pipefs_sb = rpc_get_sb_net(net);
214 if (!pipefs_sb)
215 return NULL;
216 dentry = nfs4blocklayout_register_sb(pipefs_sb, pipe);
217 rpc_put_sb_net(net);
218 return dentry;
219}
220
221static void nfs4blocklayout_unregister_net(struct net *net,
222 struct rpc_pipe *pipe)
223{
224 struct super_block *pipefs_sb;
225
226 pipefs_sb = rpc_get_sb_net(net);
227 if (pipefs_sb) {
228 nfs4blocklayout_unregister_sb(pipefs_sb, pipe);
229 rpc_put_sb_net(net);
230 }
231}
232
233static int nfs4blocklayout_net_init(struct net *net)
234{
235 struct nfs_net *nn = net_generic(net, nfs_net_id);
236 struct dentry *dentry;
237
238 mutex_init(&nn->bl_mutex);
239 init_waitqueue_head(&nn->bl_wq);
240 nn->bl_device_pipe = rpc_mkpipe_data(&bl_upcall_ops, 0);
241 if (IS_ERR(nn->bl_device_pipe))
242 return PTR_ERR(nn->bl_device_pipe);
243 dentry = nfs4blocklayout_register_net(net, nn->bl_device_pipe);
244 if (IS_ERR(dentry)) {
245 rpc_destroy_pipe_data(nn->bl_device_pipe);
246 return PTR_ERR(dentry);
247 }
248 nn->bl_device_pipe->dentry = dentry;
249 return 0;
250}
251
252static void nfs4blocklayout_net_exit(struct net *net)
253{
254 struct nfs_net *nn = net_generic(net, nfs_net_id);
255
256 nfs4blocklayout_unregister_net(net, nn->bl_device_pipe);
257 rpc_destroy_pipe_data(nn->bl_device_pipe);
258 nn->bl_device_pipe = NULL;
259}
260
261static struct pernet_operations nfs4blocklayout_net_ops = {
262 .init = nfs4blocklayout_net_init,
263 .exit = nfs4blocklayout_net_exit,
264};
265
266int __init bl_init_pipefs(void)
267{
268 int ret;
269
270 ret = rpc_pipefs_notifier_register(&nfs4blocklayout_block);
271 if (ret)
272 goto out;
273 ret = register_pernet_subsys(&nfs4blocklayout_net_ops);
274 if (ret)
275 goto out_unregister_notifier;
276 return 0;
277
278out_unregister_notifier:
279 rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
280out:
281 return ret;
282}
283
284void bl_cleanup_pipefs(void)
285{
286 rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
287 unregister_pernet_subsys(&nfs4blocklayout_net_ops);
288}
289
