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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)
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +030090 sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_SIZE;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070091
David Howells9249e172012-06-25 12:55:37 +010092 sb->s_flags |= MS_ACTIVE | MS_DIRSYNC | MS_NOATIME;
Aneesh Kumar K.Vdb5841d2011-02-28 17:03:59 +053093 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);
Tejun Heo412a19b2015-06-08 14:57:31 +0900133 goto free_session;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500134 }
135
David Howells9249e172012-06-25 12:55:37 +0100136 sb = sget(fs_type, NULL, v9fs_set_super, flags, v9ses);
David Howells454e2392006-06-23 02:02:57 -0700137 if (IS_ERR(sb)) {
138 retval = PTR_ERR(sb);
Sripathi Kodif0853122010-07-12 20:07:23 +0530139 goto clunk_fid;
David Howells454e2392006-06-23 02:02:57 -0700140 }
Abhishek Kulkarni4b53e4b2009-08-17 16:42:28 -0500141 v9fs_fill_super(sb, v9ses, flags, data);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700142
Dominique Martinetfb89b452014-01-10 13:44:09 +0100143 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
Al Viro98cd3fb2011-01-12 17:10:55 -0500144 sb->s_d_op = &v9fs_cached_dentry_operations;
145 else
146 sb->s_d_op = &v9fs_dentry_operations;
147
Aneesh Kumar K.V45089142011-07-25 18:06:33 +0000148 inode = v9fs_get_inode(sb, S_IFDIR | mode, 0);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700149 if (IS_ERR(inode)) {
150 retval = PTR_ERR(inode);
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500151 goto release_sb;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700152 }
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530153
Al Viro48fde702012-01-08 22:15:13 -0500154 root = d_make_root(inode);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700155 if (!root) {
156 retval = -ENOMEM;
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500157 goto release_sb;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700158 }
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700159 sb->s_root = root;
Sripathi Kodif0853122010-07-12 20:07:23 +0530160 if (v9fs_proto_dotl(v9ses)) {
161 struct p9_stat_dotl *st = NULL;
162 st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
163 if (IS_ERR(st)) {
164 retval = PTR_ERR(st);
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000165 goto release_sb;
Sripathi Kodif0853122010-07-12 20:07:23 +0530166 }
David Howells2b0143b2015-03-17 22:25:59 +0000167 d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
168 v9fs_stat2inode_dotl(st, d_inode(root));
Sripathi Kodif0853122010-07-12 20:07:23 +0530169 kfree(st);
170 } else {
171 struct p9_wstat *st = NULL;
172 st = p9_client_stat(fid);
173 if (IS_ERR(st)) {
174 retval = PTR_ERR(st);
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000175 goto release_sb;
Sripathi Kodif0853122010-07-12 20:07:23 +0530176 }
177
David Howells2b0143b2015-03-17 22:25:59 +0000178 d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
179 v9fs_stat2inode(st, d_inode(root), sb);
Sripathi Kodif0853122010-07-12 20:07:23 +0530180
181 p9stat_free(st);
182 kfree(st);
183 }
Aneesh Kumar K.V85ff8722010-09-28 00:27:39 +0530184 retval = v9fs_get_acl(inode, fid);
185 if (retval)
186 goto release_sb;
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530187 v9fs_fid_add(root, fid);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700188
Joe Perches5d385152011-11-28 10:40:46 -0800189 p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
Al Virod2d1ea92010-07-25 23:56:43 +0400190 return dget(sb->s_root);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700191
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500192clunk_fid:
193 p9_client_clunk(fid);
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500194 v9fs_session_close(v9ses);
Tejun Heo412a19b2015-06-08 14:57:31 +0900195free_session:
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500196 kfree(v9ses);
Al Virod2d1ea92010-07-25 23:56:43 +0400197 return ERR_PTR(retval);
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530198
Abhishek Kulkarni1b5ab3e2009-07-19 13:41:52 -0600199release_sb:
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000200 /*
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530201 * we will do the session_close and root dentry release
202 * in the below call. But we need to clunk fid, because we haven't
203 * attached the fid to dentry so it won't get clunked
204 * automatically.
Aneesh Kumar K.V5c25f342010-08-24 10:30:49 +0000205 */
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530206 p9_client_clunk(fid);
Abhishek Kulkarni1b5ab3e2009-07-19 13:41:52 -0600207 deactivate_locked_super(sb);
Al Virod2d1ea92010-07-25 23:56:43 +0400208 return ERR_PTR(retval);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700209}
210
211/**
212 * v9fs_kill_super - Kill Superblock
213 * @s: superblock
214 *
215 */
216
217static void v9fs_kill_super(struct super_block *s)
218{
219 struct v9fs_session_info *v9ses = s->s_fs_info;
220
Joe Perches5d385152011-11-28 10:40:46 -0800221 p9_debug(P9_DEBUG_VFS, " %p\n", s);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700222
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700223 kill_anon_super(s);
Aneesh Kumar K.Vdf5d8c82011-03-24 20:38:35 +0530224
Aneesh Kumar K.V6d96d3a2010-03-29 18:13:59 -0500225 v9fs_session_cancel(v9ses);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700226 v9fs_session_close(v9ses);
227 kfree(v9ses);
Abhishek Kulkarni1b5ab3e2009-07-19 13:41:52 -0600228 s->s_fs_info = NULL;
Joe Perches5d385152011-11-28 10:40:46 -0800229 p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700230}
231
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700232static void
Al Viro42faad92008-04-24 07:21:56 -0400233v9fs_umount_begin(struct super_block *sb)
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700234{
Alessio Igor Bogani67e55202009-04-24 09:06:53 +0200235 struct v9fs_session_info *v9ses;
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700236
Alessio Igor Bogani67e55202009-04-24 09:06:53 +0200237 v9ses = sb->s_fs_info;
Aneesh Kumar K.V6d96d3a2010-03-29 18:13:59 -0500238 v9fs_session_begin_cancel(v9ses);
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700239}
240
Sripathi Kodibda8e772010-03-25 12:45:30 +0000241static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
242{
243 struct v9fs_session_info *v9ses;
244 struct p9_fid *fid;
245 struct p9_rstatfs rs;
246 int res;
247
248 fid = v9fs_fid_lookup(dentry);
249 if (IS_ERR(fid)) {
250 res = PTR_ERR(fid);
251 goto done;
252 }
253
Aneesh Kumar K.V42869c82011-03-08 16:39:50 +0530254 v9ses = v9fs_dentry2v9ses(dentry);
Sripathi Kodibda8e772010-03-25 12:45:30 +0000255 if (v9fs_proto_dotl(v9ses)) {
256 res = p9_client_statfs(fid, &rs);
257 if (res == 0) {
Jim Garlick5bdad932011-06-30 09:03:38 -0700258 buf->f_type = rs.type;
Sripathi Kodibda8e772010-03-25 12:45:30 +0000259 buf->f_bsize = rs.bsize;
260 buf->f_blocks = rs.blocks;
261 buf->f_bfree = rs.bfree;
262 buf->f_bavail = rs.bavail;
263 buf->f_files = rs.files;
264 buf->f_ffree = rs.ffree;
265 buf->f_fsid.val[0] = rs.fsid & 0xFFFFFFFFUL;
266 buf->f_fsid.val[1] = (rs.fsid >> 32) & 0xFFFFFFFFUL;
267 buf->f_namelen = rs.namelen;
268 }
269 if (res != -ENOSYS)
270 goto done;
271 }
272 res = simple_statfs(dentry, buf);
273done:
274 return res;
275}
276
Aneesh Kumar K.Vedd73cf2011-02-28 17:04:05 +0530277static int v9fs_drop_inode(struct inode *inode)
278{
279 struct v9fs_session_info *v9ses;
280 v9ses = v9fs_inode2v9ses(inode);
Dominique Martinetfb89b452014-01-10 13:44:09 +0100281 if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
Aneesh Kumar K.Vedd73cf2011-02-28 17:04:05 +0530282 return generic_drop_inode(inode);
283 /*
284 * in case of non cached mode always drop the
285 * the inode because we want the inode attribute
286 * to always match that on the server.
287 */
288 return 1;
289}
290
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530291static int v9fs_write_inode(struct inode *inode,
292 struct writeback_control *wbc)
293{
294 int ret;
295 struct p9_wstat wstat;
296 struct v9fs_inode *v9inode;
297 /*
298 * send an fsync request to server irrespective of
299 * wbc->sync_mode.
300 */
Joe Perches5d385152011-11-28 10:40:46 -0800301 p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530302 v9inode = V9FS_I(inode);
303 if (!v9inode->writeback_fid)
304 return 0;
305 v9fs_blank_wstat(&wstat);
306
307 ret = p9_client_wstat(v9inode->writeback_fid, &wstat);
308 if (ret < 0) {
309 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
310 return ret;
311 }
312 return 0;
313}
314
315static int v9fs_write_inode_dotl(struct inode *inode,
316 struct writeback_control *wbc)
317{
318 int ret;
319 struct v9fs_inode *v9inode;
320 /*
321 * send an fsync request to server irrespective of
322 * wbc->sync_mode.
323 */
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530324 v9inode = V9FS_I(inode);
Dominique Martinetfb89b452014-01-10 13:44:09 +0100325 p9_debug(P9_DEBUG_VFS, "%s: inode %p, writeback_fid %p\n",
326 __func__, inode, v9inode->writeback_fid);
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530327 if (!v9inode->writeback_fid)
328 return 0;
Dominique Martinetfb89b452014-01-10 13:44:09 +0100329
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530330 ret = p9_client_fsync(v9inode->writeback_fid, 0);
331 if (ret < 0) {
332 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
333 return ret;
334 }
335 return 0;
336}
337
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800338static const struct super_operations v9fs_super_ops = {
Abhishek Kulkarni60e78d22009-09-23 13:00:27 -0500339 .alloc_inode = v9fs_alloc_inode,
340 .destroy_inode = v9fs_destroy_inode,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700341 .statfs = simple_statfs,
Al Virob57922d2010-06-07 14:34:48 -0400342 .evict_inode = v9fs_evict_inode,
Abhishek Kulkarni4b53e4b2009-08-17 16:42:28 -0500343 .show_options = generic_show_options,
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700344 .umount_begin = v9fs_umount_begin,
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530345 .write_inode = v9fs_write_inode,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700346};
347
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000348static const struct super_operations v9fs_super_ops_dotl = {
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000349 .alloc_inode = v9fs_alloc_inode,
350 .destroy_inode = v9fs_destroy_inode,
Sripathi Kodibda8e772010-03-25 12:45:30 +0000351 .statfs = v9fs_statfs,
Aneesh Kumar K.Vedd73cf2011-02-28 17:04:05 +0530352 .drop_inode = v9fs_drop_inode,
Al Virob57922d2010-06-07 14:34:48 -0400353 .evict_inode = v9fs_evict_inode,
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000354 .show_options = generic_show_options,
355 .umount_begin = v9fs_umount_begin,
Aneesh Kumar K.Vc2ed3882011-03-23 15:11:27 +0530356 .write_inode = v9fs_write_inode_dotl,
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000357};
358
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700359struct file_system_type v9fs_fs_type = {
Eric Van Hensbergen67543e52006-03-25 03:07:29 -0800360 .name = "9p",
Al Virod2d1ea92010-07-25 23:56:43 +0400361 .mount = v9fs_mount,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700362 .kill_sb = v9fs_kill_super,
363 .owner = THIS_MODULE,
Jeff Laytonecf3d1f2013-02-20 11:19:05 -0500364 .fs_flags = FS_RENAME_DOES_D_MOVE,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700365};
Eric W. Biederman7f78e032013-03-02 19:39:14 -0800366MODULE_ALIAS_FS("9p");