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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *
4 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
5 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/errno.h>
11#include <linux/fs.h>
12#include <linux/file.h>
13#include <linux/stat.h>
14#include <linux/string.h>
15#include <linux/pagemap.h>
16#include <linux/mount.h>
17#include <linux/sched.h>
18#include <linux/slab.h>
19#include <linux/statfs.h>
20#include <linux/magic.h>
21#include <linux/fscache.h>
22#include <net/9p/9p.h>
23#include <net/9p/client.h>
24
25#include "v9fs.h"
26#include "v9fs_vfs.h"
27#include "fid.h"
28#include "xattr.h"
29#include "acl.h"
30
31static const struct super_operations v9fs_super_ops, v9fs_super_ops_dotl;
32
33/**
34 * v9fs_set_super - set the superblock
35 * @s: super block
36 * @data: file system specific data
37 *
38 */
39
40static int v9fs_set_super(struct super_block *s, void *data)
41{
42 s->s_fs_info = data;
43 return set_anon_super(s, data);
44}
45
46/**
47 * v9fs_fill_super - populate superblock with info
48 * @sb: superblock
49 * @v9ses: session information
50 * @flags: flags propagated from v9fs_mount()
51 *
52 */
53
54static int
55v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
56 int flags)
57{
58 int ret;
59
60 sb->s_maxbytes = MAX_LFS_FILESIZE;
61 sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
62 sb->s_blocksize = 1 << sb->s_blocksize_bits;
63 sb->s_magic = V9FS_MAGIC;
64 if (v9fs_proto_dotl(v9ses)) {
65 sb->s_op = &v9fs_super_ops_dotl;
66 if (!(v9ses->flags & V9FS_NO_XATTR))
67 sb->s_xattr = v9fs_xattr_handlers;
68 } else {
69 sb->s_op = &v9fs_super_ops;
70 sb->s_time_max = U32_MAX;
71 }
72
73 sb->s_time_min = 0;
74
75 ret = super_setup_bdi(sb);
76 if (ret)
77 return ret;
78
79 if (!v9ses->cache) {
80 sb->s_bdi->ra_pages = 0;
81 sb->s_bdi->io_pages = 0;
82 } else {
83 sb->s_bdi->ra_pages = v9ses->maxdata >> PAGE_SHIFT;
84 sb->s_bdi->io_pages = v9ses->maxdata >> PAGE_SHIFT;
85 }
86
87 sb->s_flags |= SB_ACTIVE;
88
89#ifdef CONFIG_9P_FS_POSIX_ACL
90 if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL)
91 sb->s_flags |= SB_POSIXACL;
92#endif
93
94 return 0;
95}
96
97/**
98 * v9fs_mount - mount a superblock
99 * @fs_type: file system type
100 * @flags: mount flags
101 * @dev_name: device name that was mounted
102 * @data: mount options
103 *
104 */
105
106static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
107 const char *dev_name, void *data)
108{
109 struct super_block *sb = NULL;
110 struct inode *inode = NULL;
111 struct dentry *root = NULL;
112 struct v9fs_session_info *v9ses = NULL;
113 struct p9_fid *fid;
114 int retval = 0;
115
116 p9_debug(P9_DEBUG_VFS, "\n");
117
118 v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
119 if (!v9ses)
120 return ERR_PTR(-ENOMEM);
121
122 fid = v9fs_session_init(v9ses, dev_name, data);
123 if (IS_ERR(fid)) {
124 retval = PTR_ERR(fid);
125 goto free_session;
126 }
127
128 sb = sget(fs_type, NULL, v9fs_set_super, flags, v9ses);
129 if (IS_ERR(sb)) {
130 retval = PTR_ERR(sb);
131 goto clunk_fid;
132 }
133 retval = v9fs_fill_super(sb, v9ses, flags);
134 if (retval)
135 goto release_sb;
136
137 if (v9ses->cache & (CACHE_META|CACHE_LOOSE))
138 sb->s_d_op = &v9fs_cached_dentry_operations;
139 else
140 sb->s_d_op = &v9fs_dentry_operations;
141
142 inode = v9fs_get_new_inode_from_fid(v9ses, fid, sb);
143 if (IS_ERR(inode)) {
144 retval = PTR_ERR(inode);
145 goto release_sb;
146 }
147
148 root = d_make_root(inode);
149 if (!root) {
150 retval = -ENOMEM;
151 goto release_sb;
152 }
153 sb->s_root = root;
154 retval = v9fs_get_acl(inode, fid);
155 if (retval)
156 goto release_sb;
157 v9fs_fid_add(root, &fid);
158
159 p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
160 return dget(sb->s_root);
161
162clunk_fid:
163 p9_fid_put(fid);
164 v9fs_session_close(v9ses);
165free_session:
166 kfree(v9ses);
167 return ERR_PTR(retval);
168
169release_sb:
170 /*
171 * we will do the session_close and root dentry release
172 * in the below call. But we need to clunk fid, because we haven't
173 * attached the fid to dentry so it won't get clunked
174 * automatically.
175 */
176 p9_fid_put(fid);
177 deactivate_locked_super(sb);
178 return ERR_PTR(retval);
179}
180
181/**
182 * v9fs_kill_super - Kill Superblock
183 * @s: superblock
184 *
185 */
186
187static void v9fs_kill_super(struct super_block *s)
188{
189 struct v9fs_session_info *v9ses = s->s_fs_info;
190
191 p9_debug(P9_DEBUG_VFS, " %p\n", s);
192
193 kill_anon_super(s);
194
195 v9fs_session_cancel(v9ses);
196 v9fs_session_close(v9ses);
197 kfree(v9ses);
198 s->s_fs_info = NULL;
199 p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
200}
201
202static void
203v9fs_umount_begin(struct super_block *sb)
204{
205 struct v9fs_session_info *v9ses;
206
207 v9ses = sb->s_fs_info;
208 v9fs_session_begin_cancel(v9ses);
209}
210
211static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
212{
213 struct v9fs_session_info *v9ses;
214 struct p9_fid *fid;
215 struct p9_rstatfs rs;
216 int res;
217
218 fid = v9fs_fid_lookup(dentry);
219 if (IS_ERR(fid)) {
220 res = PTR_ERR(fid);
221 goto done;
222 }
223
224 v9ses = v9fs_dentry2v9ses(dentry);
225 if (v9fs_proto_dotl(v9ses)) {
226 res = p9_client_statfs(fid, &rs);
227 if (res == 0) {
228 buf->f_type = rs.type;
229 buf->f_bsize = rs.bsize;
230 buf->f_blocks = rs.blocks;
231 buf->f_bfree = rs.bfree;
232 buf->f_bavail = rs.bavail;
233 buf->f_files = rs.files;
234 buf->f_ffree = rs.ffree;
235 buf->f_fsid = u64_to_fsid(rs.fsid);
236 buf->f_namelen = rs.namelen;
237 }
238 if (res != -ENOSYS)
239 goto done;
240 }
241 res = simple_statfs(dentry, buf);
242done:
243 p9_fid_put(fid);
244 return res;
245}
246
247static int v9fs_drop_inode(struct inode *inode)
248{
249 struct v9fs_session_info *v9ses;
250
251 v9ses = v9fs_inode2v9ses(inode);
252 if (v9ses->cache & (CACHE_META|CACHE_LOOSE))
253 return generic_drop_inode(inode);
254 /*
255 * in case of non cached mode always drop the
256 * inode because we want the inode attribute
257 * to always match that on the server.
258 */
259 return 1;
260}
261
262static int v9fs_write_inode(struct inode *inode,
263 struct writeback_control *wbc)
264{
265 /*
266 * send an fsync request to server irrespective of
267 * wbc->sync_mode.
268 */
269 p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
270 return netfs_unpin_writeback(inode, wbc);
271}
272
273static int v9fs_write_inode_dotl(struct inode *inode,
274 struct writeback_control *wbc)
275{
276
277 p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
278
279 return netfs_unpin_writeback(inode, wbc);
280}
281
282static const struct super_operations v9fs_super_ops = {
283 .alloc_inode = v9fs_alloc_inode,
284 .free_inode = v9fs_free_inode,
285 .statfs = simple_statfs,
286 .drop_inode = v9fs_drop_inode,
287 .evict_inode = v9fs_evict_inode,
288 .show_options = v9fs_show_options,
289 .umount_begin = v9fs_umount_begin,
290 .write_inode = v9fs_write_inode,
291};
292
293static const struct super_operations v9fs_super_ops_dotl = {
294 .alloc_inode = v9fs_alloc_inode,
295 .free_inode = v9fs_free_inode,
296 .statfs = v9fs_statfs,
297 .drop_inode = v9fs_drop_inode,
298 .evict_inode = v9fs_evict_inode,
299 .show_options = v9fs_show_options,
300 .umount_begin = v9fs_umount_begin,
301 .write_inode = v9fs_write_inode_dotl,
302};
303
304struct file_system_type v9fs_fs_type = {
305 .name = "9p",
306 .mount = v9fs_mount,
307 .kill_sb = v9fs_kill_super,
308 .owner = THIS_MODULE,
309 .fs_flags = FS_RENAME_DOES_D_MOVE,
310};
311MODULE_ALIAS_FS("9p");
1/*
2 * linux/fs/9p/vfs_super.c
3 *
4 * This file contians superblock ops for 9P2000. It is intended that
5 * you mount this file system on directories.
6 *
7 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
8 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2
12 * as published by the Free Software Foundation.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to:
21 * Free Software Foundation
22 * 51 Franklin Street, Fifth Floor
23 * Boston, MA 02111-1301 USA
24 *
25 */
26
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/errno.h>
30#include <linux/fs.h>
31#include <linux/file.h>
32#include <linux/stat.h>
33#include <linux/string.h>
34#include <linux/inet.h>
35#include <linux/pagemap.h>
36#include <linux/seq_file.h>
37#include <linux/mount.h>
38#include <linux/idr.h>
39#include <linux/sched.h>
40#include <linux/slab.h>
41#include <linux/statfs.h>
42#include <linux/magic.h>
43#include <net/9p/9p.h>
44#include <net/9p/client.h>
45
46#include "v9fs.h"
47#include "v9fs_vfs.h"
48#include "fid.h"
49#include "xattr.h"
50#include "acl.h"
51
52static const struct super_operations v9fs_super_ops, v9fs_super_ops_dotl;
53
54/**
55 * v9fs_set_super - set the superblock
56 * @s: super block
57 * @data: file system specific data
58 *
59 */
60
61static int v9fs_set_super(struct super_block *s, void *data)
62{
63 s->s_fs_info = data;
64 return set_anon_super(s, data);
65}
66
67/**
68 * v9fs_fill_super - populate superblock with info
69 * @sb: superblock
70 * @v9ses: session information
71 * @flags: flags propagated from v9fs_mount()
72 *
73 */
74
75static void
76v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
77 int flags, void *data)
78{
79 sb->s_maxbytes = MAX_LFS_FILESIZE;
80 sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
81 sb->s_blocksize = 1 << sb->s_blocksize_bits;
82 sb->s_magic = V9FS_MAGIC;
83 if (v9fs_proto_dotl(v9ses)) {
84 sb->s_op = &v9fs_super_ops_dotl;
85 sb->s_xattr = v9fs_xattr_handlers;
86 } else
87 sb->s_op = &v9fs_super_ops;
88 sb->s_bdi = &v9ses->bdi;
89 if (v9ses->cache)
90 sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_CACHE_SIZE;
91
92 sb->s_flags |= MS_ACTIVE | MS_DIRSYNC | MS_NOATIME;
93 if (!v9ses->cache)
94 sb->s_flags |= MS_SYNCHRONOUS;
95
96#ifdef CONFIG_9P_FS_POSIX_ACL
97 if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL)
98 sb->s_flags |= MS_POSIXACL;
99#endif
100
101 save_mount_options(sb, data);
102}
103
104/**
105 * v9fs_mount - mount a superblock
106 * @fs_type: file system type
107 * @flags: mount flags
108 * @dev_name: device name that was mounted
109 * @data: mount options
110 *
111 */
112
113static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
114 const char *dev_name, void *data)
115{
116 struct super_block *sb = NULL;
117 struct inode *inode = NULL;
118 struct dentry *root = NULL;
119 struct v9fs_session_info *v9ses = NULL;
120 umode_t mode = S_IRWXUGO | S_ISVTX;
121 struct p9_fid *fid;
122 int retval = 0;
123
124 p9_debug(P9_DEBUG_VFS, "\n");
125
126 v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
127 if (!v9ses)
128 return ERR_PTR(-ENOMEM);
129
130 fid = v9fs_session_init(v9ses, dev_name, data);
131 if (IS_ERR(fid)) {
132 retval = PTR_ERR(fid);
133 /*
134 * we need to call session_close to tear down some
135 * of the data structure setup by session_init
136 */
137 goto close_session;
138 }
139
140 sb = sget(fs_type, NULL, v9fs_set_super, flags, v9ses);
141 if (IS_ERR(sb)) {
142 retval = PTR_ERR(sb);
143 goto clunk_fid;
144 }
145 v9fs_fill_super(sb, v9ses, flags, data);
146
147 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
148 sb->s_d_op = &v9fs_cached_dentry_operations;
149 else
150 sb->s_d_op = &v9fs_dentry_operations;
151
152 inode = v9fs_get_inode(sb, S_IFDIR | mode, 0);
153 if (IS_ERR(inode)) {
154 retval = PTR_ERR(inode);
155 goto release_sb;
156 }
157
158 root = d_make_root(inode);
159 if (!root) {
160 retval = -ENOMEM;
161 goto release_sb;
162 }
163 sb->s_root = root;
164 if (v9fs_proto_dotl(v9ses)) {
165 struct p9_stat_dotl *st = NULL;
166 st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
167 if (IS_ERR(st)) {
168 retval = PTR_ERR(st);
169 goto release_sb;
170 }
171 root->d_inode->i_ino = v9fs_qid2ino(&st->qid);
172 v9fs_stat2inode_dotl(st, root->d_inode);
173 kfree(st);
174 } else {
175 struct p9_wstat *st = NULL;
176 st = p9_client_stat(fid);
177 if (IS_ERR(st)) {
178 retval = PTR_ERR(st);
179 goto release_sb;
180 }
181
182 root->d_inode->i_ino = v9fs_qid2ino(&st->qid);
183 v9fs_stat2inode(st, root->d_inode, sb);
184
185 p9stat_free(st);
186 kfree(st);
187 }
188 retval = v9fs_get_acl(inode, fid);
189 if (retval)
190 goto release_sb;
191 v9fs_fid_add(root, fid);
192
193 p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
194 return dget(sb->s_root);
195
196clunk_fid:
197 p9_client_clunk(fid);
198close_session:
199 v9fs_session_close(v9ses);
200 kfree(v9ses);
201 return ERR_PTR(retval);
202
203release_sb:
204 /*
205 * we will do the session_close and root dentry release
206 * in the below call. But we need to clunk fid, because we haven't
207 * attached the fid to dentry so it won't get clunked
208 * automatically.
209 */
210 p9_client_clunk(fid);
211 deactivate_locked_super(sb);
212 return ERR_PTR(retval);
213}
214
215/**
216 * v9fs_kill_super - Kill Superblock
217 * @s: superblock
218 *
219 */
220
221static void v9fs_kill_super(struct super_block *s)
222{
223 struct v9fs_session_info *v9ses = s->s_fs_info;
224
225 p9_debug(P9_DEBUG_VFS, " %p\n", s);
226
227 kill_anon_super(s);
228
229 v9fs_session_cancel(v9ses);
230 v9fs_session_close(v9ses);
231 kfree(v9ses);
232 s->s_fs_info = NULL;
233 p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
234}
235
236static void
237v9fs_umount_begin(struct super_block *sb)
238{
239 struct v9fs_session_info *v9ses;
240
241 v9ses = sb->s_fs_info;
242 v9fs_session_begin_cancel(v9ses);
243}
244
245static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
246{
247 struct v9fs_session_info *v9ses;
248 struct p9_fid *fid;
249 struct p9_rstatfs rs;
250 int res;
251
252 fid = v9fs_fid_lookup(dentry);
253 if (IS_ERR(fid)) {
254 res = PTR_ERR(fid);
255 goto done;
256 }
257
258 v9ses = v9fs_dentry2v9ses(dentry);
259 if (v9fs_proto_dotl(v9ses)) {
260 res = p9_client_statfs(fid, &rs);
261 if (res == 0) {
262 buf->f_type = rs.type;
263 buf->f_bsize = rs.bsize;
264 buf->f_blocks = rs.blocks;
265 buf->f_bfree = rs.bfree;
266 buf->f_bavail = rs.bavail;
267 buf->f_files = rs.files;
268 buf->f_ffree = rs.ffree;
269 buf->f_fsid.val[0] = rs.fsid & 0xFFFFFFFFUL;
270 buf->f_fsid.val[1] = (rs.fsid >> 32) & 0xFFFFFFFFUL;
271 buf->f_namelen = rs.namelen;
272 }
273 if (res != -ENOSYS)
274 goto done;
275 }
276 res = simple_statfs(dentry, buf);
277done:
278 return res;
279}
280
281static int v9fs_drop_inode(struct inode *inode)
282{
283 struct v9fs_session_info *v9ses;
284 v9ses = v9fs_inode2v9ses(inode);
285 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
286 return generic_drop_inode(inode);
287 /*
288 * in case of non cached mode always drop the
289 * the inode because we want the inode attribute
290 * to always match that on the server.
291 */
292 return 1;
293}
294
295static int v9fs_write_inode(struct inode *inode,
296 struct writeback_control *wbc)
297{
298 int ret;
299 struct p9_wstat wstat;
300 struct v9fs_inode *v9inode;
301 /*
302 * send an fsync request to server irrespective of
303 * wbc->sync_mode.
304 */
305 p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
306 v9inode = V9FS_I(inode);
307 if (!v9inode->writeback_fid)
308 return 0;
309 v9fs_blank_wstat(&wstat);
310
311 ret = p9_client_wstat(v9inode->writeback_fid, &wstat);
312 if (ret < 0) {
313 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
314 return ret;
315 }
316 return 0;
317}
318
319static int v9fs_write_inode_dotl(struct inode *inode,
320 struct writeback_control *wbc)
321{
322 int ret;
323 struct v9fs_inode *v9inode;
324 /*
325 * send an fsync request to server irrespective of
326 * wbc->sync_mode.
327 */
328 v9inode = V9FS_I(inode);
329 p9_debug(P9_DEBUG_VFS, "%s: inode %p, writeback_fid %p\n",
330 __func__, inode, v9inode->writeback_fid);
331 if (!v9inode->writeback_fid)
332 return 0;
333
334 ret = p9_client_fsync(v9inode->writeback_fid, 0);
335 if (ret < 0) {
336 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
337 return ret;
338 }
339 return 0;
340}
341
342static const struct super_operations v9fs_super_ops = {
343 .alloc_inode = v9fs_alloc_inode,
344 .destroy_inode = v9fs_destroy_inode,
345 .statfs = simple_statfs,
346 .evict_inode = v9fs_evict_inode,
347 .show_options = generic_show_options,
348 .umount_begin = v9fs_umount_begin,
349 .write_inode = v9fs_write_inode,
350};
351
352static const struct super_operations v9fs_super_ops_dotl = {
353 .alloc_inode = v9fs_alloc_inode,
354 .destroy_inode = v9fs_destroy_inode,
355 .statfs = v9fs_statfs,
356 .drop_inode = v9fs_drop_inode,
357 .evict_inode = v9fs_evict_inode,
358 .show_options = generic_show_options,
359 .umount_begin = v9fs_umount_begin,
360 .write_inode = v9fs_write_inode_dotl,
361};
362
363struct file_system_type v9fs_fs_type = {
364 .name = "9p",
365 .mount = v9fs_mount,
366 .kill_sb = v9fs_kill_super,
367 .owner = THIS_MODULE,
368 .fs_flags = FS_RENAME_DOES_D_MOVE,
369};
370MODULE_ALIAS_FS("9p");