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1/*
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
10 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
12 *
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>
32#include <linux/sched.h>
33#include <linux/inet.h>
34#include <linux/idr.h>
35#include <linux/slab.h>
36#include <linux/uio.h>
37#include <net/9p/9p.h>
38#include <net/9p/client.h>
39
40#include "v9fs.h"
41#include "v9fs_vfs.h"
42#include "fid.h"
43
44/**
45 * struct p9_rdir - readdir accounting
46 * @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 {
55 int head;
56 int tail;
57 uint8_t buf[];
58};
59
60/**
61 * dt_type - return file type
62 * @mistat: mistat structure
63 *
64 */
65
66static inline int dt_type(struct p9_wstat *mistat)
67{
68 unsigned long perm = mistat->mode;
69 int rettype = DT_REG;
70
71 if (perm & P9_DMDIR)
72 rettype = DT_DIR;
73 if (perm & P9_DMSYMLINK)
74 rettype = DT_LNK;
75
76 return rettype;
77}
78
79static 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
88/**
89 * 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
95static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
96{
97 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;
101}
102
103/**
104 * v9fs_dir_readdir - iterate through a directory
105 * @file: opened file structure
106 * @ctx: actor we feed the entries to
107 *
108 */
109
110static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
111{
112 bool over;
113 struct p9_wstat st;
114 int err = 0;
115 struct p9_fid *fid;
116 int buflen;
117 int reclen = 0;
118 struct p9_rdir *rdir;
119 struct kvec kvec;
120
121 p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
122 fid = file->private_data;
123
124 buflen = fid->clnt->msize - P9_IOHDRSZ;
125
126 rdir = v9fs_alloc_rdir_buf(file, buflen);
127 if (!rdir)
128 return -ENOMEM;
129 kvec.iov_base = rdir->buf;
130 kvec.iov_len = buflen;
131
132 while (1) {
133 if (rdir->tail == rdir->head) {
134 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)
140 return err;
141 if (n == 0)
142 return 0;
143
144 rdir->head = 0;
145 rdir->tail = n;
146 }
147 while (rdir->head < rdir->tail) {
148 p9stat_init(&st);
149 err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
150 rdir->tail - rdir->head, &st);
151 if (err) {
152 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
153 p9stat_free(&st);
154 return -EIO;
155 }
156 reclen = st.size+2;
157
158 over = !dir_emit(ctx, st.name, strlen(st.name),
159 v9fs_qid2ino(&st.qid), dt_type(&st));
160 p9stat_free(&st);
161 if (over)
162 return 0;
163
164 rdir->head += reclen;
165 ctx->pos += reclen;
166 }
167 }
168}
169
170/**
171 * v9fs_dir_readdir_dotl - iterate through a directory
172 * @file: opened file structure
173 * @ctx: actor we feed the entries to
174 *
175 */
176static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
177{
178 int err = 0;
179 struct p9_fid *fid;
180 int buflen;
181 struct p9_rdir *rdir;
182 struct p9_dirent curdirent;
183
184 p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
185 fid = file->private_data;
186
187 buflen = fid->clnt->msize - P9_READDIRHDRSZ;
188
189 rdir = v9fs_alloc_rdir_buf(file, buflen);
190 if (!rdir)
191 return -ENOMEM;
192
193 while (1) {
194 if (rdir->tail == rdir->head) {
195 err = p9_client_readdir(fid, rdir->buf, buflen,
196 ctx->pos);
197 if (err <= 0)
198 return err;
199
200 rdir->head = 0;
201 rdir->tail = err;
202 }
203
204 while (rdir->head < rdir->tail) {
205
206 err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
207 rdir->tail - rdir->head,
208 &curdirent);
209 if (err < 0) {
210 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
211 return -EIO;
212 }
213
214 if (!dir_emit(ctx, curdirent.d_name,
215 strlen(curdirent.d_name),
216 v9fs_qid2ino(&curdirent.qid),
217 curdirent.d_type))
218 return 0;
219
220 ctx->pos = curdirent.d_off;
221 rdir->head += err;
222 }
223 }
224}
225
226
227/**
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{
236 struct p9_fid *fid;
237
238 fid = filp->private_data;
239 p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
240 inode, filp, fid ? fid->fid : -1);
241 if (fid)
242 p9_client_clunk(fid);
243 return 0;
244}
245
246const struct file_operations v9fs_dir_operations = {
247 .read = generic_read_dir,
248 .llseek = generic_file_llseek,
249 .iterate_shared = v9fs_dir_readdir,
250 .open = v9fs_file_open,
251 .release = v9fs_dir_release,
252};
253
254const struct file_operations v9fs_dir_operations_dotl = {
255 .read = generic_read_dir,
256 .llseek = generic_file_llseek,
257 .iterate_shared = v9fs_dir_readdir_dotl,
258 .open = v9fs_file_open,
259 .release = v9fs_dir_release,
260 .fsync = v9fs_file_fsync_dotl,
261};
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * This file contains vfs directory ops for the 9P2000 protocol.
4 *
5 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
6 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
7 */
8
9#include <linux/module.h>
10#include <linux/errno.h>
11#include <linux/fs.h>
12#include <linux/file.h>
13#include <linux/stat.h>
14#include <linux/string.h>
15#include <linux/sched.h>
16#include <linux/slab.h>
17#include <linux/uio.h>
18#include <linux/fscache.h>
19#include <net/9p/9p.h>
20#include <net/9p/client.h>
21
22#include "v9fs.h"
23#include "v9fs_vfs.h"
24#include "fid.h"
25
26/**
27 * struct p9_rdir - readdir accounting
28 * @head: start offset of current dirread buffer
29 * @tail: end offset of current dirread buffer
30 * @buf: dirread buffer
31 *
32 * private structure for keeping track of readdir
33 * allocated on demand
34 */
35
36struct p9_rdir {
37 int head;
38 int tail;
39 uint8_t buf[];
40};
41
42/**
43 * dt_type - return file type
44 * @mistat: mistat structure
45 *
46 */
47
48static inline int dt_type(struct p9_wstat *mistat)
49{
50 unsigned long perm = mistat->mode;
51 int rettype = DT_REG;
52
53 if (perm & P9_DMDIR)
54 rettype = DT_DIR;
55 if (perm & P9_DMSYMLINK)
56 rettype = DT_LNK;
57
58 return rettype;
59}
60
61/**
62 * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
63 * @filp: opened file structure
64 * @buflen: Length in bytes of buffer to allocate
65 *
66 */
67
68static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
69{
70 struct p9_fid *fid = filp->private_data;
71
72 if (!fid->rdir)
73 fid->rdir = kzalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
74 return fid->rdir;
75}
76
77/**
78 * v9fs_dir_readdir - iterate through a directory
79 * @file: opened file structure
80 * @ctx: actor we feed the entries to
81 *
82 */
83
84static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
85{
86 bool over;
87 struct p9_wstat st;
88 int err = 0;
89 struct p9_fid *fid;
90 int buflen;
91 struct p9_rdir *rdir;
92 struct kvec kvec;
93
94 p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
95 fid = file->private_data;
96
97 buflen = fid->clnt->msize - P9_IOHDRSZ;
98
99 rdir = v9fs_alloc_rdir_buf(file, buflen);
100 if (!rdir)
101 return -ENOMEM;
102 kvec.iov_base = rdir->buf;
103 kvec.iov_len = buflen;
104
105 while (1) {
106 if (rdir->tail == rdir->head) {
107 struct iov_iter to;
108 int n;
109
110 iov_iter_kvec(&to, ITER_DEST, &kvec, 1, buflen);
111 n = p9_client_read(file->private_data, ctx->pos, &to,
112 &err);
113 if (err)
114 return err;
115 if (n == 0)
116 return 0;
117
118 rdir->head = 0;
119 rdir->tail = n;
120 }
121 while (rdir->head < rdir->tail) {
122 err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
123 rdir->tail - rdir->head, &st);
124 if (err <= 0) {
125 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
126 return -EIO;
127 }
128
129 over = !dir_emit(ctx, st.name, strlen(st.name),
130 QID2INO(&st.qid), dt_type(&st));
131 p9stat_free(&st);
132 if (over)
133 return 0;
134
135 rdir->head += err;
136 ctx->pos += err;
137 }
138 }
139}
140
141/**
142 * v9fs_dir_readdir_dotl - iterate through a directory
143 * @file: opened file structure
144 * @ctx: actor we feed the entries to
145 *
146 */
147static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
148{
149 int err = 0;
150 struct p9_fid *fid;
151 int buflen;
152 struct p9_rdir *rdir;
153 struct p9_dirent curdirent;
154
155 p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
156 fid = file->private_data;
157
158 buflen = fid->clnt->msize - P9_READDIRHDRSZ;
159
160 rdir = v9fs_alloc_rdir_buf(file, buflen);
161 if (!rdir)
162 return -ENOMEM;
163
164 while (1) {
165 if (rdir->tail == rdir->head) {
166 err = p9_client_readdir(fid, rdir->buf, buflen,
167 ctx->pos);
168 if (err <= 0)
169 return err;
170
171 rdir->head = 0;
172 rdir->tail = err;
173 }
174
175 while (rdir->head < rdir->tail) {
176
177 err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
178 rdir->tail - rdir->head,
179 &curdirent);
180 if (err < 0) {
181 p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
182 return -EIO;
183 }
184
185 if (!dir_emit(ctx, curdirent.d_name,
186 strlen(curdirent.d_name),
187 QID2INO(&curdirent.qid),
188 curdirent.d_type))
189 return 0;
190
191 ctx->pos = curdirent.d_off;
192 rdir->head += err;
193 }
194 }
195}
196
197
198/**
199 * v9fs_dir_release - close a directory or a file
200 * @inode: inode of the directory or file
201 * @filp: file pointer to a directory or file
202 *
203 */
204
205int v9fs_dir_release(struct inode *inode, struct file *filp)
206{
207 struct v9fs_inode *v9inode = V9FS_I(inode);
208 struct p9_fid *fid;
209 __le32 version;
210 loff_t i_size;
211 int retval = 0, put_err;
212
213 fid = filp->private_data;
214 p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
215 inode, filp, fid ? fid->fid : -1);
216
217 if (fid) {
218 if ((S_ISREG(inode->i_mode)) && (filp->f_mode & FMODE_WRITE))
219 retval = filemap_fdatawrite(inode->i_mapping);
220
221 spin_lock(&inode->i_lock);
222 hlist_del(&fid->ilist);
223 spin_unlock(&inode->i_lock);
224 put_err = p9_fid_put(fid);
225 retval = retval < 0 ? retval : put_err;
226 }
227
228 if ((filp->f_mode & FMODE_WRITE)) {
229 version = cpu_to_le32(v9inode->qid.version);
230 i_size = i_size_read(inode);
231 fscache_unuse_cookie(v9fs_inode_cookie(v9inode),
232 &version, &i_size);
233 } else {
234 fscache_unuse_cookie(v9fs_inode_cookie(v9inode), NULL, NULL);
235 }
236 return retval;
237}
238
239const struct file_operations v9fs_dir_operations = {
240 .read = generic_read_dir,
241 .llseek = generic_file_llseek,
242 .iterate_shared = v9fs_dir_readdir,
243 .open = v9fs_file_open,
244 .release = v9fs_dir_release,
245};
246
247const struct file_operations v9fs_dir_operations_dotl = {
248 .read = generic_read_dir,
249 .llseek = generic_file_llseek,
250 .iterate_shared = v9fs_dir_readdir_dotl,
251 .open = v9fs_file_open,
252 .release = v9fs_dir_release,
253 .fsync = v9fs_file_fsync_dotl,
254};