Merge tag '9p-for-5.4' of git://github.com/martinetd/linux
[linux-2.6-block.git] / fs / 9p / vfs_super.c
CommitLineData
1f327613 1// SPDX-License-Identifier: GPL-2.0-only
9e82cf6a
EVH
2/*
3 * linux/fs/9p/vfs_super.c
4 *
5 * This file contians superblock ops for 9P2000. It is intended that
6 * you mount this file system on directories.
7 *
8 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
9 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9e82cf6a
EVH
10 */
11
12#include <linux/kernel.h>
9e82cf6a
EVH
13#include <linux/module.h>
14#include <linux/errno.h>
15#include <linux/fs.h>
16#include <linux/file.h>
17#include <linux/stat.h>
18#include <linux/string.h>
9e82cf6a
EVH
19#include <linux/inet.h>
20#include <linux/pagemap.h>
9e82cf6a
EVH
21#include <linux/mount.h>
22#include <linux/idr.h>
e8edc6e0 23#include <linux/sched.h>
5a0e3ad6 24#include <linux/slab.h>
bda8e775 25#include <linux/statfs.h>
368c09d2 26#include <linux/magic.h>
bd238fb4
LI
27#include <net/9p/9p.h>
28#include <net/9p/client.h>
9e82cf6a 29
9e82cf6a 30#include "v9fs.h"
9e82cf6a 31#include "v9fs_vfs.h"
9e82cf6a 32#include "fid.h"
ebf46264 33#include "xattr.h"
85ff872d 34#include "acl.h"
9e82cf6a 35
9b6533c9 36static const struct super_operations v9fs_super_ops, v9fs_super_ops_dotl;
9e82cf6a 37
9e82cf6a
EVH
38/**
39 * v9fs_set_super - set the superblock
40 * @s: super block
41 * @data: file system specific data
42 *
43 */
44
45static int v9fs_set_super(struct super_block *s, void *data)
46{
47 s->s_fs_info = data;
48 return set_anon_super(s, data);
49}
50
51/**
52 * v9fs_fill_super - populate superblock with info
53 * @sb: superblock
54 * @v9ses: session information
d2d1ea93 55 * @flags: flags propagated from v9fs_mount()
9e82cf6a
EVH
56 *
57 */
58
71304feb 59static int
9e82cf6a 60v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
aafee43b 61 int flags)
9e82cf6a 62{
71304feb
JK
63 int ret;
64
9e82cf6a
EVH
65 sb->s_maxbytes = MAX_LFS_FILESIZE;
66 sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
67 sb->s_blocksize = 1 << sb->s_blocksize_bits;
68 sb->s_magic = V9FS_MAGIC;
ebf46264 69 if (v9fs_proto_dotl(v9ses)) {
9b6533c9 70 sb->s_op = &v9fs_super_ops_dotl;
ebf46264 71 sb->s_xattr = v9fs_xattr_handlers;
d5c6e2d5 72 } else {
9b6533c9 73 sb->s_op = &v9fs_super_ops;
d5c6e2d5
DD
74 sb->s_time_max = U32_MAX;
75 }
76
77 sb->s_time_min = 0;
71304feb
JK
78
79 ret = super_setup_bdi(sb);
80 if (ret)
81 return ret;
82
6b365604 83 if (v9ses->cache)
b5420237 84 sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
9e82cf6a 85
7ff3c204 86 sb->s_flags |= SB_ACTIVE | SB_DIRSYNC;
db5841d4 87 if (!v9ses->cache)
1751e8a6 88 sb->s_flags |= SB_SYNCHRONOUS;
4b53e4b5 89
85ff872d 90#ifdef CONFIG_9P_FS_POSIX_ACL
e782ef71 91 if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL)
1751e8a6 92 sb->s_flags |= SB_POSIXACL;
85ff872d
AK
93#endif
94
71304feb 95 return 0;
9e82cf6a
EVH
96}
97
98/**
d2d1ea93 99 * v9fs_mount - mount a superblock
9e82cf6a
EVH
100 * @fs_type: file system type
101 * @flags: mount flags
102 * @dev_name: device name that was mounted
103 * @data: mount options
104 *
105 */
106
d2d1ea93
AV
107static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
108 const char *dev_name, void *data)
9e82cf6a
EVH
109{
110 struct super_block *sb = NULL;
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EVH
111 struct inode *inode = NULL;
112 struct dentry *root = NULL;
113 struct v9fs_session_info *v9ses = NULL;
3eda0de6 114 umode_t mode = S_IRWXUGO | S_ISVTX;
bd238fb4 115 struct p9_fid *fid;
9e82cf6a
EVH
116 int retval = 0;
117
5d385153 118 p9_debug(P9_DEBUG_VFS, "\n");
9e82cf6a 119
1dac06b2 120 v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
9e82cf6a 121 if (!v9ses)
d2d1ea93 122 return ERR_PTR(-ENOMEM);
9e82cf6a 123
bd238fb4
LI
124 fid = v9fs_session_init(v9ses, dev_name, data);
125 if (IS_ERR(fid)) {
126 retval = PTR_ERR(fid);
412a19b6 127 goto free_session;
bd238fb4
LI
128 }
129
9249e17f 130 sb = sget(fs_type, NULL, v9fs_set_super, flags, v9ses);
454e2398
DH
131 if (IS_ERR(sb)) {
132 retval = PTR_ERR(sb);
f0853122 133 goto clunk_fid;
454e2398 134 }
aafee43b 135 retval = v9fs_fill_super(sb, v9ses, flags);
71304feb
JK
136 if (retval)
137 goto release_sb;
9e82cf6a 138
fb89b45c 139 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
98cd3fb0
AV
140 sb->s_d_op = &v9fs_cached_dentry_operations;
141 else
142 sb->s_d_op = &v9fs_dentry_operations;
143
45089142 144 inode = v9fs_get_inode(sb, S_IFDIR | mode, 0);
9e82cf6a
EVH
145 if (IS_ERR(inode)) {
146 retval = PTR_ERR(inode);
887b3ece 147 goto release_sb;
9e82cf6a 148 }
df5d8c80 149
48fde701 150 root = d_make_root(inode);
9e82cf6a
EVH
151 if (!root) {
152 retval = -ENOMEM;
887b3ece 153 goto release_sb;
9e82cf6a 154 }
9e82cf6a 155 sb->s_root = root;
f0853122
SK
156 if (v9fs_proto_dotl(v9ses)) {
157 struct p9_stat_dotl *st = NULL;
158 st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
159 if (IS_ERR(st)) {
160 retval = PTR_ERR(st);
5c25f347 161 goto release_sb;
f0853122 162 }
2b0143b5 163 d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
5e3cc1ee 164 v9fs_stat2inode_dotl(st, d_inode(root), 0);
f0853122
SK
165 kfree(st);
166 } else {
167 struct p9_wstat *st = NULL;
168 st = p9_client_stat(fid);
169 if (IS_ERR(st)) {
170 retval = PTR_ERR(st);
5c25f347 171 goto release_sb;
f0853122
SK
172 }
173
2b0143b5 174 d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
5e3cc1ee 175 v9fs_stat2inode(st, d_inode(root), sb, 0);
f0853122
SK
176
177 p9stat_free(st);
178 kfree(st);
179 }
85ff872d
AK
180 retval = v9fs_get_acl(inode, fid);
181 if (retval)
182 goto release_sb;
df5d8c80 183 v9fs_fid_add(root, fid);
9e82cf6a 184
5d385153 185 p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
d2d1ea93 186 return dget(sb->s_root);
9e82cf6a 187
887b3ece
EVH
188clunk_fid:
189 p9_client_clunk(fid);
887b3ece 190 v9fs_session_close(v9ses);
412a19b6 191free_session:
887b3ece 192 kfree(v9ses);
d2d1ea93 193 return ERR_PTR(retval);
df5d8c80 194
1b5ab3e8 195release_sb:
5c25f347 196 /*
df5d8c80
AK
197 * we will do the session_close and root dentry release
198 * in the below call. But we need to clunk fid, because we haven't
199 * attached the fid to dentry so it won't get clunked
200 * automatically.
5c25f347 201 */
df5d8c80 202 p9_client_clunk(fid);
1b5ab3e8 203 deactivate_locked_super(sb);
d2d1ea93 204 return ERR_PTR(retval);
9e82cf6a
EVH
205}
206
207/**
208 * v9fs_kill_super - Kill Superblock
209 * @s: superblock
210 *
211 */
212
213static void v9fs_kill_super(struct super_block *s)
214{
215 struct v9fs_session_info *v9ses = s->s_fs_info;
216
5d385153 217 p9_debug(P9_DEBUG_VFS, " %p\n", s);
9e82cf6a 218
9e82cf6a 219 kill_anon_super(s);
df5d8c80 220
6d96d3ab 221 v9fs_session_cancel(v9ses);
9e82cf6a
EVH
222 v9fs_session_close(v9ses);
223 kfree(v9ses);
1b5ab3e8 224 s->s_fs_info = NULL;
5d385153 225 p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
9e82cf6a
EVH
226}
227
322b329a 228static void
42faad99 229v9fs_umount_begin(struct super_block *sb)
322b329a 230{
67e55205 231 struct v9fs_session_info *v9ses;
322b329a 232
67e55205 233 v9ses = sb->s_fs_info;
6d96d3ab 234 v9fs_session_begin_cancel(v9ses);
322b329a
EVH
235}
236
bda8e775
SK
237static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
238{
239 struct v9fs_session_info *v9ses;
240 struct p9_fid *fid;
241 struct p9_rstatfs rs;
242 int res;
243
244 fid = v9fs_fid_lookup(dentry);
245 if (IS_ERR(fid)) {
246 res = PTR_ERR(fid);
247 goto done;
248 }
249
42869c8a 250 v9ses = v9fs_dentry2v9ses(dentry);
bda8e775
SK
251 if (v9fs_proto_dotl(v9ses)) {
252 res = p9_client_statfs(fid, &rs);
253 if (res == 0) {
5bdad933 254 buf->f_type = rs.type;
bda8e775
SK
255 buf->f_bsize = rs.bsize;
256 buf->f_blocks = rs.blocks;
257 buf->f_bfree = rs.bfree;
258 buf->f_bavail = rs.bavail;
259 buf->f_files = rs.files;
260 buf->f_ffree = rs.ffree;
261 buf->f_fsid.val[0] = rs.fsid & 0xFFFFFFFFUL;
262 buf->f_fsid.val[1] = (rs.fsid >> 32) & 0xFFFFFFFFUL;
263 buf->f_namelen = rs.namelen;
264 }
265 if (res != -ENOSYS)
266 goto done;
267 }
268 res = simple_statfs(dentry, buf);
269done:
270 return res;
271}
272
edd73cf5
AK
273static int v9fs_drop_inode(struct inode *inode)
274{
275 struct v9fs_session_info *v9ses;
276 v9ses = v9fs_inode2v9ses(inode);
fb89b45c 277 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
edd73cf5
AK
278 return generic_drop_inode(inode);
279 /*
280 * in case of non cached mode always drop the
281 * the inode because we want the inode attribute
282 * to always match that on the server.
283 */
284 return 1;
285}
286
c2ed3880
AK
287static int v9fs_write_inode(struct inode *inode,
288 struct writeback_control *wbc)
289{
290 int ret;
291 struct p9_wstat wstat;
292 struct v9fs_inode *v9inode;
293 /*
294 * send an fsync request to server irrespective of
295 * wbc->sync_mode.
296 */
5d385153 297 p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
c2ed3880
AK
298 v9inode = V9FS_I(inode);
299 if (!v9inode->writeback_fid)
300 return 0;
301 v9fs_blank_wstat(&wstat);
302
303 ret = p9_client_wstat(v9inode->writeback_fid, &wstat);
304 if (ret < 0) {
305 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
306 return ret;
307 }
308 return 0;
309}
310
311static int v9fs_write_inode_dotl(struct inode *inode,
312 struct writeback_control *wbc)
313{
314 int ret;
315 struct v9fs_inode *v9inode;
316 /*
317 * send an fsync request to server irrespective of
318 * wbc->sync_mode.
319 */
c2ed3880 320 v9inode = V9FS_I(inode);
fb89b45c
DM
321 p9_debug(P9_DEBUG_VFS, "%s: inode %p, writeback_fid %p\n",
322 __func__, inode, v9inode->writeback_fid);
c2ed3880
AK
323 if (!v9inode->writeback_fid)
324 return 0;
fb89b45c 325
c2ed3880
AK
326 ret = p9_client_fsync(v9inode->writeback_fid, 0);
327 if (ret < 0) {
328 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
329 return ret;
330 }
331 return 0;
332}
333
ee9b6d61 334static const struct super_operations v9fs_super_ops = {
60e78d2c 335 .alloc_inode = v9fs_alloc_inode,
5e8a0770 336 .free_inode = v9fs_free_inode,
9e82cf6a 337 .statfs = simple_statfs,
b57922d9 338 .evict_inode = v9fs_evict_inode,
c4fac910 339 .show_options = v9fs_show_options,
322b329a 340 .umount_begin = v9fs_umount_begin,
c2ed3880 341 .write_inode = v9fs_write_inode,
9e82cf6a
EVH
342};
343
9b6533c9 344static const struct super_operations v9fs_super_ops_dotl = {
9b6533c9 345 .alloc_inode = v9fs_alloc_inode,
5e8a0770 346 .free_inode = v9fs_free_inode,
bda8e775 347 .statfs = v9fs_statfs,
edd73cf5 348 .drop_inode = v9fs_drop_inode,
b57922d9 349 .evict_inode = v9fs_evict_inode,
c4fac910 350 .show_options = v9fs_show_options,
9b6533c9 351 .umount_begin = v9fs_umount_begin,
c2ed3880 352 .write_inode = v9fs_write_inode_dotl,
9b6533c9
SK
353};
354
9e82cf6a 355struct file_system_type v9fs_fs_type = {
67543e50 356 .name = "9p",
d2d1ea93 357 .mount = v9fs_mount,
9e82cf6a
EVH
358 .kill_sb = v9fs_kill_super,
359 .owner = THIS_MODULE,
ecf3d1f1 360 .fs_flags = FS_RENAME_DOES_D_MOVE,
9e82cf6a 361};
7f78e035 362MODULE_ALIAS_FS("9p");