This source file includes following definitions.
- nfs4_write_inode
- nfs4_evict_inode
- nfs4_remote_mount
- nfs_do_root_mount
- nfs_find_referral_count
- nfs_referral_loop_protect
- nfs_referral_loop_unprotect
- nfs_follow_remote_path
- nfs4_try_mount
- nfs4_remote_referral_mount
- nfs4_referral_mount
- init_nfs_v4
- exit_nfs_v4
1
2
3
4
5 #include <linux/init.h>
6 #include <linux/module.h>
7 #include <linux/nfs4_mount.h>
8 #include <linux/nfs_fs.h>
9 #include "delegation.h"
10 #include "internal.h"
11 #include "nfs4_fs.h"
12 #include "nfs4idmap.h"
13 #include "dns_resolve.h"
14 #include "pnfs.h"
15 #include "nfs.h"
16
17 #define NFSDBG_FACILITY NFSDBG_VFS
18
19 static int nfs4_write_inode(struct inode *inode, struct writeback_control *wbc);
20 static void nfs4_evict_inode(struct inode *inode);
21 static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
22 int flags, const char *dev_name, void *raw_data);
23 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
24 int flags, const char *dev_name, void *raw_data);
25 static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
26 int flags, const char *dev_name, void *raw_data);
27
28 static struct file_system_type nfs4_remote_fs_type = {
29 .owner = THIS_MODULE,
30 .name = "nfs4",
31 .mount = nfs4_remote_mount,
32 .kill_sb = nfs_kill_super,
33 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
34 };
35
36 static struct file_system_type nfs4_remote_referral_fs_type = {
37 .owner = THIS_MODULE,
38 .name = "nfs4",
39 .mount = nfs4_remote_referral_mount,
40 .kill_sb = nfs_kill_super,
41 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
42 };
43
44 struct file_system_type nfs4_referral_fs_type = {
45 .owner = THIS_MODULE,
46 .name = "nfs4",
47 .mount = nfs4_referral_mount,
48 .kill_sb = nfs_kill_super,
49 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
50 };
51
52 static const struct super_operations nfs4_sops = {
53 .alloc_inode = nfs_alloc_inode,
54 .free_inode = nfs_free_inode,
55 .write_inode = nfs4_write_inode,
56 .drop_inode = nfs_drop_inode,
57 .statfs = nfs_statfs,
58 .evict_inode = nfs4_evict_inode,
59 .umount_begin = nfs_umount_begin,
60 .show_options = nfs_show_options,
61 .show_devname = nfs_show_devname,
62 .show_path = nfs_show_path,
63 .show_stats = nfs_show_stats,
64 .remount_fs = nfs_remount,
65 };
66
67 struct nfs_subversion nfs_v4 = {
68 .owner = THIS_MODULE,
69 .nfs_fs = &nfs4_fs_type,
70 .rpc_vers = &nfs_version4,
71 .rpc_ops = &nfs_v4_clientops,
72 .sops = &nfs4_sops,
73 .xattr = nfs4_xattr_handlers,
74 };
75
76 static int nfs4_write_inode(struct inode *inode, struct writeback_control *wbc)
77 {
78 int ret = nfs_write_inode(inode, wbc);
79
80 if (ret == 0)
81 ret = pnfs_layoutcommit_inode(inode,
82 wbc->sync_mode == WB_SYNC_ALL);
83 return ret;
84 }
85
86
87
88
89
90
91 static void nfs4_evict_inode(struct inode *inode)
92 {
93 truncate_inode_pages_final(&inode->i_data);
94 clear_inode(inode);
95
96 nfs_inode_return_delegation_noreclaim(inode);
97
98 pnfs_return_layout(inode);
99 pnfs_destroy_layout(NFS_I(inode));
100
101 nfs_clear_inode(inode);
102 }
103
104
105
106
107 static struct dentry *
108 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
109 const char *dev_name, void *info)
110 {
111 struct nfs_mount_info *mount_info = info;
112 struct nfs_server *server;
113 struct dentry *mntroot = ERR_PTR(-ENOMEM);
114
115 mount_info->set_security = nfs_set_sb_security;
116
117
118 server = nfs4_create_server(mount_info, &nfs_v4);
119 if (IS_ERR(server)) {
120 mntroot = ERR_CAST(server);
121 goto out;
122 }
123
124 mntroot = nfs_fs_mount_common(server, flags, dev_name, mount_info, &nfs_v4);
125
126 out:
127 return mntroot;
128 }
129
130 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
131 int flags, void *data, const char *hostname)
132 {
133 struct vfsmount *root_mnt;
134 char *root_devname;
135 size_t len;
136
137 len = strlen(hostname) + 5;
138 root_devname = kmalloc(len, GFP_KERNEL);
139 if (root_devname == NULL)
140 return ERR_PTR(-ENOMEM);
141
142 if (strchr(hostname, ':'))
143 snprintf(root_devname, len, "[%s]:/", hostname);
144 else
145 snprintf(root_devname, len, "%s:/", hostname);
146 root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
147 kfree(root_devname);
148 return root_mnt;
149 }
150
151 struct nfs_referral_count {
152 struct list_head list;
153 const struct task_struct *task;
154 unsigned int referral_count;
155 };
156
157 static LIST_HEAD(nfs_referral_count_list);
158 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
159
160 static struct nfs_referral_count *nfs_find_referral_count(void)
161 {
162 struct nfs_referral_count *p;
163
164 list_for_each_entry(p, &nfs_referral_count_list, list) {
165 if (p->task == current)
166 return p;
167 }
168 return NULL;
169 }
170
171 #define NFS_MAX_NESTED_REFERRALS 2
172
173 static int nfs_referral_loop_protect(void)
174 {
175 struct nfs_referral_count *p, *new;
176 int ret = -ENOMEM;
177
178 new = kmalloc(sizeof(*new), GFP_KERNEL);
179 if (!new)
180 goto out;
181 new->task = current;
182 new->referral_count = 1;
183
184 ret = 0;
185 spin_lock(&nfs_referral_count_list_lock);
186 p = nfs_find_referral_count();
187 if (p != NULL) {
188 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
189 ret = -ELOOP;
190 else
191 p->referral_count++;
192 } else {
193 list_add(&new->list, &nfs_referral_count_list);
194 new = NULL;
195 }
196 spin_unlock(&nfs_referral_count_list_lock);
197 kfree(new);
198 out:
199 return ret;
200 }
201
202 static void nfs_referral_loop_unprotect(void)
203 {
204 struct nfs_referral_count *p;
205
206 spin_lock(&nfs_referral_count_list_lock);
207 p = nfs_find_referral_count();
208 p->referral_count--;
209 if (p->referral_count == 0)
210 list_del(&p->list);
211 else
212 p = NULL;
213 spin_unlock(&nfs_referral_count_list_lock);
214 kfree(p);
215 }
216
217 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
218 const char *export_path)
219 {
220 struct dentry *dentry;
221 int err;
222
223 if (IS_ERR(root_mnt))
224 return ERR_CAST(root_mnt);
225
226 err = nfs_referral_loop_protect();
227 if (err) {
228 mntput(root_mnt);
229 return ERR_PTR(err);
230 }
231
232 dentry = mount_subtree(root_mnt, export_path);
233 nfs_referral_loop_unprotect();
234
235 return dentry;
236 }
237
238 struct dentry *nfs4_try_mount(int flags, const char *dev_name,
239 struct nfs_mount_info *mount_info,
240 struct nfs_subversion *nfs_mod)
241 {
242 char *export_path;
243 struct vfsmount *root_mnt;
244 struct dentry *res;
245 struct nfs_parsed_mount_data *data = mount_info->parsed;
246
247 dfprintk(MOUNT, "--> nfs4_try_mount()\n");
248
249 export_path = data->nfs_server.export_path;
250 data->nfs_server.export_path = "/";
251 root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, mount_info,
252 data->nfs_server.hostname);
253 data->nfs_server.export_path = export_path;
254
255 res = nfs_follow_remote_path(root_mnt, export_path);
256
257 dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n",
258 PTR_ERR_OR_ZERO(res),
259 IS_ERR(res) ? " [error]" : "");
260 return res;
261 }
262
263 static struct dentry *
264 nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
265 const char *dev_name, void *raw_data)
266 {
267 struct nfs_mount_info mount_info = {
268 .fill_super = nfs_fill_super,
269 .set_security = nfs_clone_sb_security,
270 .cloned = raw_data,
271 };
272 struct nfs_server *server;
273 struct dentry *mntroot = ERR_PTR(-ENOMEM);
274
275 dprintk("--> nfs4_referral_get_sb()\n");
276
277 mount_info.mntfh = nfs_alloc_fhandle();
278 if (mount_info.cloned == NULL || mount_info.mntfh == NULL)
279 goto out;
280
281
282 server = nfs4_create_referral_server(mount_info.cloned, mount_info.mntfh);
283 if (IS_ERR(server)) {
284 mntroot = ERR_CAST(server);
285 goto out;
286 }
287
288 mntroot = nfs_fs_mount_common(server, flags, dev_name, &mount_info, &nfs_v4);
289 out:
290 nfs_free_fhandle(mount_info.mntfh);
291 return mntroot;
292 }
293
294
295
296
297 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
298 int flags, const char *dev_name, void *raw_data)
299 {
300 struct nfs_clone_mount *data = raw_data;
301 char *export_path;
302 struct vfsmount *root_mnt;
303 struct dentry *res;
304
305 dprintk("--> nfs4_referral_mount()\n");
306
307 export_path = data->mnt_path;
308 data->mnt_path = "/";
309
310 root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
311 flags, data, data->hostname);
312 data->mnt_path = export_path;
313
314 res = nfs_follow_remote_path(root_mnt, export_path);
315 dprintk("<-- nfs4_referral_mount() = %d%s\n",
316 PTR_ERR_OR_ZERO(res),
317 IS_ERR(res) ? " [error]" : "");
318 return res;
319 }
320
321
322 static int __init init_nfs_v4(void)
323 {
324 int err;
325
326 err = nfs_dns_resolver_init();
327 if (err)
328 goto out;
329
330 err = nfs_idmap_init();
331 if (err)
332 goto out1;
333
334 err = nfs4_register_sysctl();
335 if (err)
336 goto out2;
337
338 register_nfs_version(&nfs_v4);
339 return 0;
340 out2:
341 nfs_idmap_quit();
342 out1:
343 nfs_dns_resolver_destroy();
344 out:
345 return err;
346 }
347
348 static void __exit exit_nfs_v4(void)
349 {
350
351 nfs4_pnfs_v3_ds_connect_unload();
352
353 unregister_nfs_version(&nfs_v4);
354 nfs4_unregister_sysctl();
355 nfs_idmap_quit();
356 nfs_dns_resolver_destroy();
357 }
358
359 MODULE_LICENSE("GPL");
360
361 module_init(init_nfs_v4);
362 module_exit(exit_nfs_v4);