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