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Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -07001/*
2 * linux/fs/9p/vfs_dir.c
3 *
4 * This file contains vfs directory ops for the 9P2000 protocol.
5 *
6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8 *
9 * This program is free software; you can redistribute it and/or modify
Eric Van Hensbergen42e8c502006-03-25 03:07:28 -080010 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070012 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to:
20 * Free Software Foundation
21 * 51 Franklin Street, Fifth Floor
22 * Boston, MA 02111-1301 USA
23 *
24 */
25
26#include <linux/module.h>
27#include <linux/errno.h>
28#include <linux/fs.h>
29#include <linux/file.h>
30#include <linux/stat.h>
31#include <linux/string.h>
Al Viro914e2632006-10-18 13:55:46 -040032#include <linux/sched.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070033#include <linux/inet.h>
34#include <linux/idr.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090035#include <linux/slab.h>
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050036#include <net/9p/9p.h>
37#include <net/9p/client.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070038
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070039#include "v9fs.h"
Latchesar Ionkov531b1092006-01-08 01:05:00 -080040#include "v9fs_vfs.h"
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070041#include "fid.h"
42
43/**
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -060044 * struct p9_rdir - readdir accounting
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -060045 * @head: start offset of current dirread buffer
46 * @tail: end offset of current dirread buffer
47 * @buf: dirread buffer
48 *
49 * private structure for keeping track of readdir
50 * allocated on demand
51 */
52
53struct p9_rdir {
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -060054 int head;
55 int tail;
Al Viro7ffdea72013-01-26 00:11:36 +000056 uint8_t buf[];
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -060057};
58
59/**
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070060 * dt_type - return file type
61 * @mistat: mistat structure
62 *
63 */
64
Eric Van Hensbergen02da3982008-10-16 08:29:30 -050065static inline int dt_type(struct p9_wstat *mistat)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070066{
67 unsigned long perm = mistat->mode;
68 int rettype = DT_REG;
69
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050070 if (perm & P9_DMDIR)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070071 rettype = DT_DIR;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050072 if (perm & P9_DMSYMLINK)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070073 rettype = DT_LNK;
74
75 return rettype;
76}
77
Aneesh Kumar K.Vfae45282010-03-06 04:44:16 +000078static void p9stat_init(struct p9_wstat *stbuf)
79{
80 stbuf->name = NULL;
81 stbuf->uid = NULL;
82 stbuf->gid = NULL;
83 stbuf->muid = NULL;
84 stbuf->extension = NULL;
85}
86
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070087/**
Sripathi Kodi7751bdb2010-06-04 13:41:26 +000088 * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
89 * @filp: opened file structure
90 * @buflen: Length in bytes of buffer to allocate
91 *
92 */
93
Al Viro7ffdea72013-01-26 00:11:36 +000094static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
Sripathi Kodi7751bdb2010-06-04 13:41:26 +000095{
Al Viro7ffdea72013-01-26 00:11:36 +000096 struct p9_fid *fid = filp->private_data;
97 if (!fid->rdir)
98 fid->rdir = kzalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
99 return fid->rdir;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000100}
101
102/**
Al Viro8f298432013-05-17 17:51:41 -0400103 * v9fs_dir_readdir - iterate through a directory
104 * @file: opened file structure
105 * @ctx: actor we feed the entries to
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700106 *
107 */
108
Al Viro8f298432013-05-17 17:51:41 -0400109static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700110{
Al Viro8f298432013-05-17 17:51:41 -0400111 bool over;
Eric Van Hensbergen02da3982008-10-16 08:29:30 -0500112 struct p9_wstat st;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600113 int err = 0;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500114 struct p9_fid *fid;
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500115 int buflen;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600116 int reclen = 0;
117 struct p9_rdir *rdir;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700118
Al Viro4b8e9922014-08-19 20:17:38 -0400119 p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
Al Viro8f298432013-05-17 17:51:41 -0400120 fid = file->private_data;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700121
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500122 buflen = fid->clnt->msize - P9_IOHDRSZ;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700123
Al Viro8f298432013-05-17 17:51:41 -0400124 rdir = v9fs_alloc_rdir_buf(file, buflen);
Al Viro7ffdea72013-01-26 00:11:36 +0000125 if (!rdir)
126 return -ENOMEM;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600127
Al Viro7ffdea72013-01-26 00:11:36 +0000128 while (1) {
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600129 if (rdir->tail == rdir->head) {
Al Viro8f298432013-05-17 17:51:41 -0400130 err = v9fs_file_readn(file, rdir->buf, NULL,
131 buflen, ctx->pos);
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600132 if (err <= 0)
Al Viro7ffdea72013-01-26 00:11:36 +0000133 return err;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600134
135 rdir->head = 0;
136 rdir->tail = err;
137 }
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600138 while (rdir->head < rdir->tail) {
Aneesh Kumar K.Vfae45282010-03-06 04:44:16 +0000139 p9stat_init(&st);
Aneesh Kumar K.V348b5902011-08-07 00:46:59 +0530140 err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
141 rdir->tail - rdir->head, &st);
Eric Van Hensbergen02da3982008-10-16 08:29:30 -0500142 if (err) {
Joe Perches5d385152011-11-28 10:40:46 -0800143 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
Eric Van Hensbergen02da3982008-10-16 08:29:30 -0500144 p9stat_free(&st);
Al Viro7ffdea72013-01-26 00:11:36 +0000145 return -EIO;
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500146 }
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600147 reclen = st.size+2;
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500148
Al Viro8f298432013-05-17 17:51:41 -0400149 over = !dir_emit(ctx, st.name, strlen(st.name),
150 v9fs_qid2ino(&st.qid), dt_type(&st));
Eric Van Hensbergen02da3982008-10-16 08:29:30 -0500151 p9stat_free(&st);
Al Viro7ffdea72013-01-26 00:11:36 +0000152 if (over)
153 return 0;
154
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600155 rdir->head += reclen;
Al Viro8f298432013-05-17 17:51:41 -0400156 ctx->pos += reclen;
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500157 }
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700158 }
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700159}
160
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000161/**
Al Viro8f298432013-05-17 17:51:41 -0400162 * v9fs_dir_readdir_dotl - iterate through a directory
163 * @file: opened file structure
164 * @ctx: actor we feed the entries to
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000165 *
166 */
Al Viro8f298432013-05-17 17:51:41 -0400167static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000168{
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000169 int err = 0;
170 struct p9_fid *fid;
171 int buflen;
172 struct p9_rdir *rdir;
173 struct p9_dirent curdirent;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000174
Al Viro4b8e9922014-08-19 20:17:38 -0400175 p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
Al Viro8f298432013-05-17 17:51:41 -0400176 fid = file->private_data;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000177
178 buflen = fid->clnt->msize - P9_READDIRHDRSZ;
179
Al Viro8f298432013-05-17 17:51:41 -0400180 rdir = v9fs_alloc_rdir_buf(file, buflen);
Al Viro7ffdea72013-01-26 00:11:36 +0000181 if (!rdir)
182 return -ENOMEM;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000183
Al Viro7ffdea72013-01-26 00:11:36 +0000184 while (1) {
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000185 if (rdir->tail == rdir->head) {
186 err = p9_client_readdir(fid, rdir->buf, buflen,
Al Viro8f298432013-05-17 17:51:41 -0400187 ctx->pos);
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000188 if (err <= 0)
Al Viro7ffdea72013-01-26 00:11:36 +0000189 return err;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000190
191 rdir->head = 0;
192 rdir->tail = err;
193 }
194
195 while (rdir->head < rdir->tail) {
196
Aneesh Kumar K.V348b5902011-08-07 00:46:59 +0530197 err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
198 rdir->tail - rdir->head,
199 &curdirent);
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000200 if (err < 0) {
Joe Perches5d385152011-11-28 10:40:46 -0800201 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
Al Viro7ffdea72013-01-26 00:11:36 +0000202 return -EIO;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000203 }
204
Al Viro8f298432013-05-17 17:51:41 -0400205 if (!dir_emit(ctx, curdirent.d_name,
206 strlen(curdirent.d_name),
207 v9fs_qid2ino(&curdirent.qid),
208 curdirent.d_type))
Al Viro7ffdea72013-01-26 00:11:36 +0000209 return 0;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000210
Al Viro8f298432013-05-17 17:51:41 -0400211 ctx->pos = curdirent.d_off;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000212 rdir->head += err;
213 }
214 }
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000215}
216
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500217
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700218/**
219 * v9fs_dir_release - close a directory
220 * @inode: inode of the directory
221 * @filp: file pointer to a directory
222 *
223 */
224
225int v9fs_dir_release(struct inode *inode, struct file *filp)
226{
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500227 struct p9_fid *fid;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700228
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500229 fid = filp->private_data;
Joe Perches5d385152011-11-28 10:40:46 -0800230 p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
231 inode, filp, fid ? fid->fid : -1);
jvrao62726a72010-08-25 16:26:21 +0000232 if (fid)
233 p9_client_clunk(fid);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700234 return 0;
235}
236
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800237const struct file_operations v9fs_dir_operations = {
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700238 .read = generic_read_dir,
Al Viro59af1582008-08-24 07:24:41 -0400239 .llseek = generic_file_llseek,
Al Viro8f298432013-05-17 17:51:41 -0400240 .iterate = v9fs_dir_readdir,
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700241 .open = v9fs_file_open,
242 .release = v9fs_dir_release,
243};
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000244
245const struct file_operations v9fs_dir_operations_dotl = {
246 .read = generic_read_dir,
247 .llseek = generic_file_llseek,
Al Viro8f298432013-05-17 17:51:41 -0400248 .iterate = v9fs_dir_readdir_dotl,
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000249 .open = v9fs_file_open,
250 .release = v9fs_dir_release,
Venkateswararao Jujjuri (JV)b165d602010-10-22 10:13:12 -0700251 .fsync = v9fs_file_fsync_dotl,
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000252};