blob: 75090feeafade9c790bb4bf0d84c8546a46819a0 [file] [log] [blame]
Bryan Schumaker129d1972012-07-16 16:39:13 -04001/*
2 * Copyright (c) 2012 Bryan Schumaker <bjschuma@netapp.com>
3 */
4#include <linux/init.h>
Bryan Schumakerfbdefd62012-07-16 16:39:20 -04005#include <linux/module.h>
Bryan Schumaker129d1972012-07-16 16:39:13 -04006#include <linux/nfs_idmap.h>
Bryan Schumakerfbdefd62012-07-16 16:39:20 -04007#include <linux/nfs4_mount.h>
Bryan Schumaker466bfe72012-07-16 16:39:14 -04008#include <linux/nfs_fs.h>
Bryan Schumaker19d87ca2012-07-30 16:05:21 -04009#include "delegation.h"
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040010#include "internal.h"
Bryan Schumaker466bfe72012-07-16 16:39:14 -040011#include "nfs4_fs.h"
Trond Myklebustc8d74d92013-06-01 11:50:58 -040012#include "dns_resolve.h"
Bryan Schumaker19d87ca2012-07-30 16:05:21 -040013#include "pnfs.h"
Bryan Schumakerab7017a2012-07-30 16:05:16 -040014#include "nfs.h"
Bryan Schumaker129d1972012-07-16 16:39:13 -040015
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040016#define NFSDBG_FACILITY NFSDBG_VFS
17
Bryan Schumaker19d87ca2012-07-30 16:05:21 -040018static int nfs4_write_inode(struct inode *inode, struct writeback_control *wbc);
19static void nfs4_evict_inode(struct inode *inode);
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040020static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
21 int flags, const char *dev_name, void *raw_data);
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040022static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
23 int flags, const char *dev_name, void *raw_data);
24static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
25 int flags, const char *dev_name, void *raw_data);
26
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040027static struct file_system_type nfs4_remote_fs_type = {
28 .owner = THIS_MODULE,
29 .name = "nfs4",
30 .mount = nfs4_remote_mount,
31 .kill_sb = nfs_kill_super,
Jeff Laytonecf3d1f2013-02-20 11:19:05 -050032 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040033};
34
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040035static struct file_system_type nfs4_remote_referral_fs_type = {
36 .owner = THIS_MODULE,
37 .name = "nfs4",
38 .mount = nfs4_remote_referral_mount,
39 .kill_sb = nfs_kill_super,
Jeff Laytonecf3d1f2013-02-20 11:19:05 -050040 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040041};
42
43struct file_system_type nfs4_referral_fs_type = {
44 .owner = THIS_MODULE,
45 .name = "nfs4",
46 .mount = nfs4_referral_mount,
47 .kill_sb = nfs_kill_super,
Jeff Laytonecf3d1f2013-02-20 11:19:05 -050048 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040049};
50
51static const struct super_operations nfs4_sops = {
52 .alloc_inode = nfs_alloc_inode,
53 .destroy_inode = nfs_destroy_inode,
54 .write_inode = nfs4_write_inode,
Trond Myklebusteed99352012-12-14 14:36:36 -050055 .drop_inode = nfs_drop_inode,
Bryan Schumakerfbdefd62012-07-16 16:39:20 -040056 .statfs = nfs_statfs,
57 .evict_inode = nfs4_evict_inode,
58 .umount_begin = nfs_umount_begin,
59 .show_options = nfs_show_options,
60 .show_devname = nfs_show_devname,
61 .show_path = nfs_show_path,
62 .show_stats = nfs_show_stats,
63 .remount_fs = nfs_remount,
64};
65
Bryan Schumakerab7017a2012-07-30 16:05:16 -040066struct nfs_subversion nfs_v4 = {
67 .owner = THIS_MODULE,
68 .nfs_fs = &nfs4_fs_type,
69 .rpc_vers = &nfs_version4,
70 .rpc_ops = &nfs_v4_clientops,
Bryan Schumaker6a744902012-07-30 16:05:20 -040071 .sops = &nfs4_sops,
72 .xattr = nfs4_xattr_handlers,
Bryan Schumakerab7017a2012-07-30 16:05:16 -040073};
74
Bryan Schumaker19d87ca2012-07-30 16:05:21 -040075static int nfs4_write_inode(struct inode *inode, struct writeback_control *wbc)
76{
77 int ret = nfs_write_inode(inode, wbc);
78
Trond Myklebust71244d92014-01-13 13:34:36 -050079 if (ret == 0)
80 ret = pnfs_layoutcommit_inode(inode,
81 wbc->sync_mode == WB_SYNC_ALL);
Bryan Schumaker19d87ca2012-07-30 16:05:21 -040082 return ret;
83}
84
85/*
86 * Clean out any remaining NFSv4 state that might be left over due
87 * to open() calls that passed nfs_atomic_lookup, but failed to call
88 * nfs_open().
89 */
90static void nfs4_evict_inode(struct inode *inode)
91{
Johannes Weiner91b0abe2014-04-03 14:47:49 -070092 truncate_inode_pages_final(&inode->i_data);
Bryan Schumaker19d87ca2012-07-30 16:05:21 -040093 clear_inode(inode);
94 pnfs_return_layout(inode);
95 pnfs_destroy_layout(NFS_I(inode));
96 /* If we are holding a delegation, return it! */
97 nfs_inode_return_delegation_noreclaim(inode);
98 /* First call standard NFS clear_inode() code */
99 nfs_clear_inode(inode);
100}
101
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400102/*
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400103 * Get the superblock for the NFS4 root partition
104 */
105static struct dentry *
106nfs4_remote_mount(struct file_system_type *fs_type, int flags,
107 const char *dev_name, void *info)
108{
109 struct nfs_mount_info *mount_info = info;
110 struct nfs_server *server;
111 struct dentry *mntroot = ERR_PTR(-ENOMEM);
112
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400113 mount_info->set_security = nfs_set_sb_security;
114
115 /* Get a volume representation */
Bryan Schumaker1179acc2012-07-30 16:05:19 -0400116 server = nfs4_create_server(mount_info, &nfs_v4);
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400117 if (IS_ERR(server)) {
118 mntroot = ERR_CAST(server);
119 goto out;
120 }
121
Bryan Schumakerab7017a2012-07-30 16:05:16 -0400122 mntroot = nfs_fs_mount_common(server, flags, dev_name, mount_info, &nfs_v4);
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400123
124out:
125 return mntroot;
126}
127
128static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
129 int flags, void *data, const char *hostname)
130{
131 struct vfsmount *root_mnt;
132 char *root_devname;
133 size_t len;
134
135 len = strlen(hostname) + 5;
136 root_devname = kmalloc(len, GFP_KERNEL);
137 if (root_devname == NULL)
138 return ERR_PTR(-ENOMEM);
139 /* Does hostname needs to be enclosed in brackets? */
140 if (strchr(hostname, ':'))
141 snprintf(root_devname, len, "[%s]:/", hostname);
142 else
143 snprintf(root_devname, len, "%s:/", hostname);
144 root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
145 kfree(root_devname);
146 return root_mnt;
147}
148
149struct nfs_referral_count {
150 struct list_head list;
151 const struct task_struct *task;
152 unsigned int referral_count;
153};
154
155static LIST_HEAD(nfs_referral_count_list);
156static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
157
158static struct nfs_referral_count *nfs_find_referral_count(void)
159{
160 struct nfs_referral_count *p;
161
162 list_for_each_entry(p, &nfs_referral_count_list, list) {
163 if (p->task == current)
164 return p;
165 }
166 return NULL;
167}
168
169#define NFS_MAX_NESTED_REFERRALS 2
170
171static int nfs_referral_loop_protect(void)
172{
173 struct nfs_referral_count *p, *new;
174 int ret = -ENOMEM;
175
176 new = kmalloc(sizeof(*new), GFP_KERNEL);
177 if (!new)
178 goto out;
179 new->task = current;
180 new->referral_count = 1;
181
182 ret = 0;
183 spin_lock(&nfs_referral_count_list_lock);
184 p = nfs_find_referral_count();
185 if (p != NULL) {
186 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
187 ret = -ELOOP;
188 else
189 p->referral_count++;
190 } else {
191 list_add(&new->list, &nfs_referral_count_list);
192 new = NULL;
193 }
194 spin_unlock(&nfs_referral_count_list_lock);
195 kfree(new);
196out:
197 return ret;
198}
199
200static void nfs_referral_loop_unprotect(void)
201{
202 struct nfs_referral_count *p;
203
204 spin_lock(&nfs_referral_count_list_lock);
205 p = nfs_find_referral_count();
206 p->referral_count--;
207 if (p->referral_count == 0)
208 list_del(&p->list);
209 else
210 p = NULL;
211 spin_unlock(&nfs_referral_count_list_lock);
212 kfree(p);
213}
214
215static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
216 const char *export_path)
217{
218 struct dentry *dentry;
219 int err;
220
221 if (IS_ERR(root_mnt))
222 return ERR_CAST(root_mnt);
223
224 err = nfs_referral_loop_protect();
225 if (err) {
226 mntput(root_mnt);
227 return ERR_PTR(err);
228 }
229
230 dentry = mount_subtree(root_mnt, export_path);
231 nfs_referral_loop_unprotect();
232
233 return dentry;
234}
235
236struct dentry *nfs4_try_mount(int flags, const char *dev_name,
Bryan Schumakerff9099f22012-07-30 16:05:18 -0400237 struct nfs_mount_info *mount_info,
238 struct nfs_subversion *nfs_mod)
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400239{
240 char *export_path;
241 struct vfsmount *root_mnt;
242 struct dentry *res;
243 struct nfs_parsed_mount_data *data = mount_info->parsed;
244
245 dfprintk(MOUNT, "--> nfs4_try_mount()\n");
246
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400247 export_path = data->nfs_server.export_path;
248 data->nfs_server.export_path = "/";
249 root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, mount_info,
250 data->nfs_server.hostname);
251 data->nfs_server.export_path = export_path;
252
253 res = nfs_follow_remote_path(root_mnt, export_path);
254
Geyslan G. Bem67062462013-10-14 17:24:16 -0300255 dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n",
256 PTR_ERR_OR_ZERO(res),
257 IS_ERR(res) ? " [error]" : "");
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400258 return res;
259}
260
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400261static struct dentry *
262nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
263 const char *dev_name, void *raw_data)
264{
265 struct nfs_mount_info mount_info = {
Bryan Schumaker6a744902012-07-30 16:05:20 -0400266 .fill_super = nfs_fill_super,
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400267 .set_security = nfs_clone_sb_security,
268 .cloned = raw_data,
269 };
270 struct nfs_server *server;
271 struct dentry *mntroot = ERR_PTR(-ENOMEM);
272
273 dprintk("--> nfs4_referral_get_sb()\n");
274
275 mount_info.mntfh = nfs_alloc_fhandle();
276 if (mount_info.cloned == NULL || mount_info.mntfh == NULL)
277 goto out;
278
279 /* create a new volume representation */
280 server = nfs4_create_referral_server(mount_info.cloned, mount_info.mntfh);
281 if (IS_ERR(server)) {
282 mntroot = ERR_CAST(server);
283 goto out;
284 }
285
Bryan Schumakerab7017a2012-07-30 16:05:16 -0400286 mntroot = nfs_fs_mount_common(server, flags, dev_name, &mount_info, &nfs_v4);
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400287out:
288 nfs_free_fhandle(mount_info.mntfh);
289 return mntroot;
290}
291
292/*
293 * Create an NFS4 server record on referral traversal
294 */
295static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
296 int flags, const char *dev_name, void *raw_data)
297{
298 struct nfs_clone_mount *data = raw_data;
299 char *export_path;
300 struct vfsmount *root_mnt;
301 struct dentry *res;
302
303 dprintk("--> nfs4_referral_mount()\n");
304
305 export_path = data->mnt_path;
306 data->mnt_path = "/";
307
308 root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
309 flags, data, data->hostname);
310 data->mnt_path = export_path;
311
312 res = nfs_follow_remote_path(root_mnt, export_path);
Geyslan G. Bem67062462013-10-14 17:24:16 -0300313 dprintk("<-- nfs4_referral_mount() = %d%s\n",
314 PTR_ERR_OR_ZERO(res),
315 IS_ERR(res) ? " [error]" : "");
Bryan Schumakerfbdefd62012-07-16 16:39:20 -0400316 return res;
317}
318
319
Bryan Schumaker89d77c82012-07-30 16:05:25 -0400320static int __init init_nfs_v4(void)
Bryan Schumaker129d1972012-07-16 16:39:13 -0400321{
322 int err;
323
Trond Myklebustc8d74d92013-06-01 11:50:58 -0400324 err = nfs_dns_resolver_init();
Bryan Schumaker129d1972012-07-16 16:39:13 -0400325 if (err)
326 goto out;
327
Trond Myklebustc8d74d92013-06-01 11:50:58 -0400328 err = nfs_idmap_init();
Bryan Schumaker466bfe72012-07-16 16:39:14 -0400329 if (err)
330 goto out1;
331
Trond Myklebustc8d74d92013-06-01 11:50:58 -0400332 err = nfs4_register_sysctl();
333 if (err)
334 goto out2;
335
Bryan Schumakerab7017a2012-07-30 16:05:16 -0400336 register_nfs_version(&nfs_v4);
Bryan Schumaker129d1972012-07-16 16:39:13 -0400337 return 0;
Trond Myklebustc8d74d92013-06-01 11:50:58 -0400338out2:
Bryan Schumaker466bfe72012-07-16 16:39:14 -0400339 nfs_idmap_quit();
Trond Myklebustc8d74d92013-06-01 11:50:58 -0400340out1:
341 nfs_dns_resolver_destroy();
Bryan Schumaker129d1972012-07-16 16:39:13 -0400342out:
343 return err;
344}
345
Bryan Schumaker89d77c82012-07-30 16:05:25 -0400346static void __exit exit_nfs_v4(void)
Bryan Schumaker129d1972012-07-16 16:39:13 -0400347{
Peng Tao5f01d952014-05-30 18:15:59 +0800348 /* Not called in the _init(), conditionally loaded */
349 nfs4_pnfs_v3_ds_connect_unload();
350
Bryan Schumakerab7017a2012-07-30 16:05:16 -0400351 unregister_nfs_version(&nfs_v4);
Bryan Schumaker466bfe72012-07-16 16:39:14 -0400352 nfs4_unregister_sysctl();
Bryan Schumaker129d1972012-07-16 16:39:13 -0400353 nfs_idmap_quit();
Trond Myklebustc8d74d92013-06-01 11:50:58 -0400354 nfs_dns_resolver_destroy();
Bryan Schumaker129d1972012-07-16 16:39:13 -0400355}
Bryan Schumaker89d77c82012-07-30 16:05:25 -0400356
357MODULE_LICENSE("GPL");
358
359module_init(init_nfs_v4);
360module_exit(exit_nfs_v4);