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Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -07001/*
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
Eric Van Hensbergen42e8c502006-03-25 03:07:28 -080011 * it under the terms of the GNU General Public License version 2
12 * as published by the Free Software Foundation.
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070013 *
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>
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070028#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>
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070034#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>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040039#include <linux/sched.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090040#include <linux/slab.h>
Sripathi Kodibda8e772010-03-25 12:45:30 +000041#include <linux/statfs.h>
M. Mohan Kumar368c09d2010-09-27 14:17:24 +053042#include <linux/magic.h>
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050043#include <net/9p/9p.h>
44#include <net/9p/client.h>
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070045
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070046#include "v9fs.h"
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070047#include "v9fs_vfs.h"
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070048#include "fid.h"
Aneesh Kumar K.Vebf46262010-05-31 13:22:56 +053049#include "xattr.h"
Aneesh Kumar K.V85ff8722010-09-28 00:27:39 +053050#include "acl.h"
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070051
Sripathi Kodi9b6533c2010-03-25 12:41:54 +000052static const struct super_operations v9fs_super_ops, v9fs_super_ops_dotl;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070053
54/**
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070055 * 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
Al Virod2d1ea92010-07-25 23:56:43 +040071 * @flags: flags propagated from v9fs_mount()
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070072 *
73 */
74
75static void
76v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
Abhishek Kulkarni4b53e4b2009-08-17 16:42:28 -050077 int flags, void *data)
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070078{
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;
Aneesh Kumar K.Vebf46262010-05-31 13:22:56 +053083 if (v9fs_proto_dotl(v9ses)) {
Sripathi Kodi9b6533c2010-03-25 12:41:54 +000084 sb->s_op = &v9fs_super_ops_dotl;
Aneesh Kumar K.Vebf46262010-05-31 13:22:56 +053085 sb->s_xattr = v9fs_xattr_handlers;
86 } else
Sripathi Kodi9b6533c2010-03-25 12:41:54 +000087 sb->s_op = &v9fs_super_ops;
Jens Axboe0ed07dd2010-04-22 11:42:00 +020088 sb->s_bdi = &v9ses->bdi;
Aneesh Kumar K.V6b365602011-02-28 17:04:03 +053089 if (v9ses->cache)
90 sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_CACHE_SIZE;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070091
Aneesh Kumar K.Vdb5841d2011-02-28 17:03:59 +053092 sb->s_flags = flags | MS_ACTIVE | MS_DIRSYNC | MS_NOATIME;
93 if (!v9ses->cache)
94 sb->s_flags |= MS_SYNCHRONOUS;
Abhishek Kulkarni4b53e4b2009-08-17 16:42:28 -050095
Aneesh Kumar K.V85ff8722010-09-28 00:27:39 +053096#ifdef CONFIG_9P_FS_POSIX_ACL
Venkateswararao Jujjuri (JV)e782ef72011-01-25 15:40:54 -080097 if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL)
Aneesh Kumar K.V76381a42010-09-28 00:27:41 +053098 sb->s_flags |= MS_POSIXACL;
Aneesh Kumar K.V85ff8722010-09-28 00:27:39 +053099#endif
100
Abhishek Kulkarni4b53e4b2009-08-17 16:42:28 -0500101 save_mount_options(sb, data);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700102}
103
104/**
Al Virod2d1ea92010-07-25 23:56:43 +0400105 * v9fs_mount - mount a superblock
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700106 * @fs_type: file system type
107 * @flags: mount flags
108 * @dev_name: device name that was mounted
109 * @data: mount options
110 *
111 */
112
Al Virod2d1ea92010-07-25 23:56:43 +0400113static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
114 const char *dev_name, void *data)
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700115{
116 struct super_block *sb = NULL;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700117 struct inode *inode = NULL;
118 struct dentry *root = NULL;
119 struct v9fs_session_info *v9ses = NULL;
Al Viro3eda0de2011-07-26 02:53:22 -0400120 umode_t mode = S_IRWXUGO | S_ISVTX;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500121 struct p9_fid *fid;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700122 int retval = 0;
123
Joe Perches5d385152011-11-28 10:40:46 -0800124 p9_debug(P9_DEBUG_VFS, "\n");
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700125
Latchesar Ionkov1dac06b2006-01-08 01:05:02 -0800126 v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700127 if (!v9ses)
Al Virod2d1ea92010-07-25 23:56:43 +0400128 return ERR_PTR(-ENOMEM);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700129
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500130 fid = v9fs_session_init(v9ses, dev_name, data);
131 if (IS_ERR(fid)) {
132 retval = PTR_ERR(fid);
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000133 /*
134 * we need to call session_close to tear down some
135 * of the data structure setup by session_init
136 */
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500137 goto close_session;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500138 }
139
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700140 sb = sget(fs_type, NULL, v9fs_set_super, v9ses);
David Howells454e2392006-06-23 02:02:57 -0700141 if (IS_ERR(sb)) {
142 retval = PTR_ERR(sb);
Sripathi Kodif0853122010-07-12 20:07:23 +0530143 goto clunk_fid;
David Howells454e2392006-06-23 02:02:57 -0700144 }
Abhishek Kulkarni4b53e4b2009-08-17 16:42:28 -0500145 v9fs_fill_super(sb, v9ses, flags, data);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700146
Al Viro98cd3fb2011-01-12 17:10:55 -0500147 if (v9ses->cache)
148 sb->s_d_op = &v9fs_cached_dentry_operations;
149 else
150 sb->s_d_op = &v9fs_dentry_operations;
151
Aneesh Kumar K.V45089142011-07-25 18:06:33 +0000152 inode = v9fs_get_inode(sb, S_IFDIR | mode, 0);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700153 if (IS_ERR(inode)) {
154 retval = PTR_ERR(inode);
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500155 goto release_sb;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700156 }
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530157
Al Viro48fde702012-01-08 22:15:13 -0500158 root = d_make_root(inode);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700159 if (!root) {
160 retval = -ENOMEM;
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500161 goto release_sb;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700162 }
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700163 sb->s_root = root;
Sripathi Kodif0853122010-07-12 20:07:23 +0530164 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);
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000169 goto release_sb;
Sripathi Kodif0853122010-07-12 20:07:23 +0530170 }
Aneesh Kumar K.V0e432702011-02-28 17:04:06 +0530171 root->d_inode->i_ino = v9fs_qid2ino(&st->qid);
Sripathi Kodif0853122010-07-12 20:07:23 +0530172 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);
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000179 goto release_sb;
Sripathi Kodif0853122010-07-12 20:07:23 +0530180 }
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 }
Aneesh Kumar K.V85ff8722010-09-28 00:27:39 +0530188 retval = v9fs_get_acl(inode, fid);
189 if (retval)
190 goto release_sb;
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530191 v9fs_fid_add(root, fid);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700192
Joe Perches5d385152011-11-28 10:40:46 -0800193 p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
Al Virod2d1ea92010-07-25 23:56:43 +0400194 return dget(sb->s_root);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700195
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500196clunk_fid:
197 p9_client_clunk(fid);
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500198close_session:
199 v9fs_session_close(v9ses);
200 kfree(v9ses);
Al Virod2d1ea92010-07-25 23:56:43 +0400201 return ERR_PTR(retval);
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530202
Abhishek Kulkarni1b5ab3e2009-07-19 13:41:52 -0600203release_sb:
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000204 /*
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530205 * 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.
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000209 */
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530210 p9_client_clunk(fid);
Abhishek Kulkarni1b5ab3e2009-07-19 13:41:52 -0600211 deactivate_locked_super(sb);
Al Virod2d1ea92010-07-25 23:56:43 +0400212 return ERR_PTR(retval);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700213}
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
Joe Perches5d385152011-11-28 10:40:46 -0800225 p9_debug(P9_DEBUG_VFS, " %p\n", s);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700226
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700227 kill_anon_super(s);
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530228
Aneesh Kumar K.V6d96d3a2010-03-29 18:13:59 -0500229 v9fs_session_cancel(v9ses);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700230 v9fs_session_close(v9ses);
231 kfree(v9ses);
Abhishek Kulkarni1b5ab3e2009-07-19 13:41:52 -0600232 s->s_fs_info = NULL;
Joe Perches5d385152011-11-28 10:40:46 -0800233 p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700234}
235
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700236static void
Al Viro42faad92008-04-24 07:21:56 -0400237v9fs_umount_begin(struct super_block *sb)
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700238{
Alessio Igor Bogani67e55202009-04-24 09:06:53 +0200239 struct v9fs_session_info *v9ses;
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700240
Alessio Igor Bogani67e55202009-04-24 09:06:53 +0200241 v9ses = sb->s_fs_info;
Aneesh Kumar K.V6d96d3a2010-03-29 18:13:59 -0500242 v9fs_session_begin_cancel(v9ses);
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700243}
244
Sripathi Kodibda8e772010-03-25 12:45:30 +0000245static 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
Aneesh Kumar K.V42869c82011-03-08 16:39:50 +0530258 v9ses = v9fs_dentry2v9ses(dentry);
Sripathi Kodibda8e772010-03-25 12:45:30 +0000259 if (v9fs_proto_dotl(v9ses)) {
260 res = p9_client_statfs(fid, &rs);
261 if (res == 0) {
Jim Garlick5bdad932011-06-30 09:03:38 -0700262 buf->f_type = rs.type;
Sripathi Kodibda8e772010-03-25 12:45:30 +0000263 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
Aneesh Kumar K.Vedd73cf2011-02-28 17:04:05 +0530281static int v9fs_drop_inode(struct inode *inode)
282{
283 struct v9fs_session_info *v9ses;
284 v9ses = v9fs_inode2v9ses(inode);
285 if (v9ses->cache)
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
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530295static 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 */
Joe Perches5d385152011-11-28 10:40:46 -0800305 p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530306 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 */
Joe Perches5d385152011-11-28 10:40:46 -0800328 p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530329 v9inode = V9FS_I(inode);
330 if (!v9inode->writeback_fid)
331 return 0;
332 ret = p9_client_fsync(v9inode->writeback_fid, 0);
333 if (ret < 0) {
334 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
335 return ret;
336 }
337 return 0;
338}
339
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800340static const struct super_operations v9fs_super_ops = {
Abhishek Kulkarni60e78d22009-09-23 13:00:27 -0500341 .alloc_inode = v9fs_alloc_inode,
342 .destroy_inode = v9fs_destroy_inode,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700343 .statfs = simple_statfs,
Al Virob57922d2010-06-07 14:34:48 -0400344 .evict_inode = v9fs_evict_inode,
Abhishek Kulkarni4b53e4b2009-08-17 16:42:28 -0500345 .show_options = generic_show_options,
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700346 .umount_begin = v9fs_umount_begin,
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530347 .write_inode = v9fs_write_inode,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700348};
349
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000350static const struct super_operations v9fs_super_ops_dotl = {
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000351 .alloc_inode = v9fs_alloc_inode,
352 .destroy_inode = v9fs_destroy_inode,
Sripathi Kodibda8e772010-03-25 12:45:30 +0000353 .statfs = v9fs_statfs,
Aneesh Kumar K.Vedd73cf2011-02-28 17:04:05 +0530354 .drop_inode = v9fs_drop_inode,
Al Virob57922d2010-06-07 14:34:48 -0400355 .evict_inode = v9fs_evict_inode,
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000356 .show_options = generic_show_options,
357 .umount_begin = v9fs_umount_begin,
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530358 .write_inode = v9fs_write_inode_dotl,
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000359};
360
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700361struct file_system_type v9fs_fs_type = {
Eric Van Hensbergen67543e52006-03-25 03:07:29 -0800362 .name = "9p",
Al Virod2d1ea92010-07-25 23:56:43 +0400363 .mount = v9fs_mount,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700364 .kill_sb = v9fs_kill_super,
365 .owner = THIS_MODULE,
Aneesh Kumar K.V823fcfd2011-02-28 17:04:07 +0530366 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700367};