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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>
Al Viroe1200fe62015-04-01 23:42:28 -040036#include <linux/uio.h>
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050037#include <net/9p/9p.h>
38#include <net/9p/client.h>
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070039
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070040#include "v9fs.h"
Latchesar Ionkov531b1092006-01-08 01:05:00 -080041#include "v9fs_vfs.h"
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070042#include "fid.h"
43
44/**
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -060045 * struct p9_rdir - readdir accounting
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -060046 * @head: start offset of current dirread buffer
47 * @tail: end offset of current dirread buffer
48 * @buf: dirread buffer
49 *
50 * private structure for keeping track of readdir
51 * allocated on demand
52 */
53
54struct p9_rdir {
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -060055 int head;
56 int tail;
Al Viro7ffdea72013-01-26 00:11:36 +000057 uint8_t buf[];
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -060058};
59
60/**
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070061 * dt_type - return file type
62 * @mistat: mistat structure
63 *
64 */
65
Eric Van Hensbergen02da3982008-10-16 08:29:30 -050066static inline int dt_type(struct p9_wstat *mistat)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070067{
68 unsigned long perm = mistat->mode;
69 int rettype = DT_REG;
70
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050071 if (perm & P9_DMDIR)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070072 rettype = DT_DIR;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050073 if (perm & P9_DMSYMLINK)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070074 rettype = DT_LNK;
75
76 return rettype;
77}
78
Aneesh Kumar K.Vfae45282010-03-06 04:44:16 +000079static void p9stat_init(struct p9_wstat *stbuf)
80{
81 stbuf->name = NULL;
82 stbuf->uid = NULL;
83 stbuf->gid = NULL;
84 stbuf->muid = NULL;
85 stbuf->extension = NULL;
86}
87
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -070088/**
Sripathi Kodi7751bdb2010-06-04 13:41:26 +000089 * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
90 * @filp: opened file structure
91 * @buflen: Length in bytes of buffer to allocate
92 *
93 */
94
Al Viro7ffdea72013-01-26 00:11:36 +000095static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
Sripathi Kodi7751bdb2010-06-04 13:41:26 +000096{
Al Viro7ffdea72013-01-26 00:11:36 +000097 struct p9_fid *fid = filp->private_data;
98 if (!fid->rdir)
99 fid->rdir = kzalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
100 return fid->rdir;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000101}
102
103/**
Al Viro8f298432013-05-17 17:51:41 -0400104 * v9fs_dir_readdir - iterate through a directory
105 * @file: opened file structure
106 * @ctx: actor we feed the entries to
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700107 *
108 */
109
Al Viro8f298432013-05-17 17:51:41 -0400110static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700111{
Al Viro8f298432013-05-17 17:51:41 -0400112 bool over;
Eric Van Hensbergen02da3982008-10-16 08:29:30 -0500113 struct p9_wstat st;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600114 int err = 0;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500115 struct p9_fid *fid;
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500116 int buflen;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600117 int reclen = 0;
118 struct p9_rdir *rdir;
Al Viroe1200fe62015-04-01 23:42:28 -0400119 struct kvec kvec;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700120
Al Viro4b8e9922014-08-19 20:17:38 -0400121 p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
Al Viro8f298432013-05-17 17:51:41 -0400122 fid = file->private_data;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700123
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500124 buflen = fid->clnt->msize - P9_IOHDRSZ;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700125
Al Viro8f298432013-05-17 17:51:41 -0400126 rdir = v9fs_alloc_rdir_buf(file, buflen);
Al Viro7ffdea72013-01-26 00:11:36 +0000127 if (!rdir)
128 return -ENOMEM;
Al Viroe1200fe62015-04-01 23:42:28 -0400129 kvec.iov_base = rdir->buf;
130 kvec.iov_len = buflen;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600131
Al Viro7ffdea72013-01-26 00:11:36 +0000132 while (1) {
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600133 if (rdir->tail == rdir->head) {
Al Viroe1200fe62015-04-01 23:42:28 -0400134 struct iov_iter to;
135 int n;
136 iov_iter_kvec(&to, READ | ITER_KVEC, &kvec, 1, buflen);
137 n = p9_client_read(file->private_data, ctx->pos, &to,
138 &err);
139 if (err)
Al Viro7ffdea72013-01-26 00:11:36 +0000140 return err;
Johannes Berg8e3c5002015-04-22 11:55:14 +0200141 if (n == 0)
142 return 0;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600143
144 rdir->head = 0;
Al Viroe1200fe62015-04-01 23:42:28 -0400145 rdir->tail = n;
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600146 }
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600147 while (rdir->head < rdir->tail) {
Aneesh Kumar K.Vfae45282010-03-06 04:44:16 +0000148 p9stat_init(&st);
Aneesh Kumar K.V348b5902011-08-07 00:46:59 +0530149 err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
150 rdir->tail - rdir->head, &st);
Eric Van Hensbergen02da3982008-10-16 08:29:30 -0500151 if (err) {
Joe Perches5d385152011-11-28 10:40:46 -0800152 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
Eric Van Hensbergen02da3982008-10-16 08:29:30 -0500153 p9stat_free(&st);
Al Viro7ffdea72013-01-26 00:11:36 +0000154 return -EIO;
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500155 }
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600156 reclen = st.size+2;
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500157
Al Viro8f298432013-05-17 17:51:41 -0400158 over = !dir_emit(ctx, st.name, strlen(st.name),
159 v9fs_qid2ino(&st.qid), dt_type(&st));
Eric Van Hensbergen02da3982008-10-16 08:29:30 -0500160 p9stat_free(&st);
Al Viro7ffdea72013-01-26 00:11:36 +0000161 if (over)
162 return 0;
163
Eric Van Hensbergen3e2796a2009-11-02 08:39:28 -0600164 rdir->head += reclen;
Al Viro8f298432013-05-17 17:51:41 -0400165 ctx->pos += reclen;
Eric Van Hensbergen06b55b42008-10-13 20:36:15 -0500166 }
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700167 }
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700168}
169
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000170/**
Al Viro8f298432013-05-17 17:51:41 -0400171 * v9fs_dir_readdir_dotl - iterate through a directory
172 * @file: opened file structure
173 * @ctx: actor we feed the entries to
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000174 *
175 */
Al Viro8f298432013-05-17 17:51:41 -0400176static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000177{
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000178 int err = 0;
179 struct p9_fid *fid;
180 int buflen;
181 struct p9_rdir *rdir;
182 struct p9_dirent curdirent;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000183
Al Viro4b8e9922014-08-19 20:17:38 -0400184 p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
Al Viro8f298432013-05-17 17:51:41 -0400185 fid = file->private_data;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000186
187 buflen = fid->clnt->msize - P9_READDIRHDRSZ;
188
Al Viro8f298432013-05-17 17:51:41 -0400189 rdir = v9fs_alloc_rdir_buf(file, buflen);
Al Viro7ffdea72013-01-26 00:11:36 +0000190 if (!rdir)
191 return -ENOMEM;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000192
Al Viro7ffdea72013-01-26 00:11:36 +0000193 while (1) {
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000194 if (rdir->tail == rdir->head) {
195 err = p9_client_readdir(fid, rdir->buf, buflen,
Al Viro8f298432013-05-17 17:51:41 -0400196 ctx->pos);
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000197 if (err <= 0)
Al Viro7ffdea72013-01-26 00:11:36 +0000198 return err;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000199
200 rdir->head = 0;
201 rdir->tail = err;
202 }
203
204 while (rdir->head < rdir->tail) {
205
Aneesh Kumar K.V348b5902011-08-07 00:46:59 +0530206 err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
207 rdir->tail - rdir->head,
208 &curdirent);
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000209 if (err < 0) {
Joe Perches5d385152011-11-28 10:40:46 -0800210 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
Al Viro7ffdea72013-01-26 00:11:36 +0000211 return -EIO;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000212 }
213
Al Viro8f298432013-05-17 17:51:41 -0400214 if (!dir_emit(ctx, curdirent.d_name,
215 strlen(curdirent.d_name),
216 v9fs_qid2ino(&curdirent.qid),
217 curdirent.d_type))
Al Viro7ffdea72013-01-26 00:11:36 +0000218 return 0;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000219
Al Viro8f298432013-05-17 17:51:41 -0400220 ctx->pos = curdirent.d_off;
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000221 rdir->head += err;
222 }
223 }
Sripathi Kodi7751bdb2010-06-04 13:41:26 +0000224}
225
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500226
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700227/**
228 * v9fs_dir_release - close a directory
229 * @inode: inode of the directory
230 * @filp: file pointer to a directory
231 *
232 */
233
234int v9fs_dir_release(struct inode *inode, struct file *filp)
235{
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500236 struct p9_fid *fid;
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700237
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500238 fid = filp->private_data;
Joe Perches5d385152011-11-28 10:40:46 -0800239 p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
240 inode, filp, fid ? fid->fid : -1);
jvrao62726a72010-08-25 16:26:21 +0000241 if (fid)
242 p9_client_clunk(fid);
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700243 return 0;
244}
245
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800246const struct file_operations v9fs_dir_operations = {
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700247 .read = generic_read_dir,
Al Viro59af1582008-08-24 07:24:41 -0400248 .llseek = generic_file_llseek,
Al Viro5963ded2016-05-01 00:08:03 -0400249 .iterate_shared = v9fs_dir_readdir,
Eric Van Hensbergene69e7fe2005-09-09 13:04:18 -0700250 .open = v9fs_file_open,
251 .release = v9fs_dir_release,
252};
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000253
254const struct file_operations v9fs_dir_operations_dotl = {
255 .read = generic_read_dir,
256 .llseek = generic_file_llseek,
Al Viro5963ded2016-05-01 00:08:03 -0400257 .iterate_shared = v9fs_dir_readdir_dotl,
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000258 .open = v9fs_file_open,
259 .release = v9fs_dir_release,
Venkateswararao Jujjuri (JV)b165d602010-10-22 10:13:12 -0700260 .fsync = v9fs_file_fsync_dotl,
Sripathi Kodi9b6533c2010-03-25 12:41:54 +0000261};