1 /*
2 * file.c
3 *
4 * Copyright (C) 1995, 1996 by Volker Lendecke
5 * Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
6 *
7 */
8
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11 #include <asm/uaccess.h>
12
13 #include <linux/time.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/fcntl.h>
17 #include <linux/stat.h>
18 #include <linux/mm.h>
19 #include <linux/vmalloc.h>
20 #include <linux/sched.h>
21
22 #include "ncp_fs.h"
23
ncp_fsync(struct file * file,loff_t start,loff_t end,int datasync)24 static int ncp_fsync(struct file *file, loff_t start, loff_t end, int datasync)
25 {
26 return filemap_write_and_wait_range(file->f_mapping, start, end);
27 }
28
29 /*
30 * Open a file with the specified read/write mode.
31 */
ncp_make_open(struct inode * inode,int right)32 int ncp_make_open(struct inode *inode, int right)
33 {
34 int error;
35 int access;
36
37 error = -EINVAL;
38 if (!inode) {
39 pr_err("%s: got NULL inode\n", __func__);
40 goto out;
41 }
42
43 ncp_dbg(1, "opened=%d, volume # %u, dir entry # %u\n",
44 atomic_read(&NCP_FINFO(inode)->opened),
45 NCP_FINFO(inode)->volNumber,
46 NCP_FINFO(inode)->dirEntNum);
47 error = -EACCES;
48 mutex_lock(&NCP_FINFO(inode)->open_mutex);
49 if (!atomic_read(&NCP_FINFO(inode)->opened)) {
50 struct ncp_entry_info finfo;
51 int result;
52
53 /* tries max. rights */
54 finfo.access = O_RDWR;
55 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
56 inode, NULL, OC_MODE_OPEN,
57 0, AR_READ | AR_WRITE, &finfo);
58 if (!result)
59 goto update;
60 /* RDWR did not succeeded, try readonly or writeonly as requested */
61 switch (right) {
62 case O_RDONLY:
63 finfo.access = O_RDONLY;
64 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
65 inode, NULL, OC_MODE_OPEN,
66 0, AR_READ, &finfo);
67 break;
68 case O_WRONLY:
69 finfo.access = O_WRONLY;
70 result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
71 inode, NULL, OC_MODE_OPEN,
72 0, AR_WRITE, &finfo);
73 break;
74 }
75 if (result) {
76 ncp_vdbg("failed, result=%d\n", result);
77 goto out_unlock;
78 }
79 /*
80 * Update the inode information.
81 */
82 update:
83 ncp_update_inode(inode, &finfo);
84 atomic_set(&NCP_FINFO(inode)->opened, 1);
85 }
86
87 access = NCP_FINFO(inode)->access;
88 ncp_vdbg("file open, access=%x\n", access);
89 if (access == right || access == O_RDWR) {
90 atomic_inc(&NCP_FINFO(inode)->opened);
91 error = 0;
92 }
93
94 out_unlock:
95 mutex_unlock(&NCP_FINFO(inode)->open_mutex);
96 out:
97 return error;
98 }
99
100 static ssize_t
ncp_file_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)101 ncp_file_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
102 {
103 struct dentry *dentry = file->f_path.dentry;
104 struct inode *inode = dentry->d_inode;
105 size_t already_read = 0;
106 off_t pos;
107 size_t bufsize;
108 int error;
109 void* freepage;
110 size_t freelen;
111
112 ncp_dbg(1, "enter %pd2\n", dentry);
113
114 pos = *ppos;
115
116 if ((ssize_t) count < 0) {
117 return -EINVAL;
118 }
119 if (!count)
120 return 0;
121 if (pos > inode->i_sb->s_maxbytes)
122 return 0;
123 if (pos + count > inode->i_sb->s_maxbytes) {
124 count = inode->i_sb->s_maxbytes - pos;
125 }
126
127 error = ncp_make_open(inode, O_RDONLY);
128 if (error) {
129 ncp_dbg(1, "open failed, error=%d\n", error);
130 return error;
131 }
132
133 bufsize = NCP_SERVER(inode)->buffer_size;
134
135 error = -EIO;
136 freelen = ncp_read_bounce_size(bufsize);
137 freepage = vmalloc(freelen);
138 if (!freepage)
139 goto outrel;
140 error = 0;
141 /* First read in as much as possible for each bufsize. */
142 while (already_read < count) {
143 int read_this_time;
144 size_t to_read = min_t(unsigned int,
145 bufsize - (pos % bufsize),
146 count - already_read);
147
148 error = ncp_read_bounce(NCP_SERVER(inode),
149 NCP_FINFO(inode)->file_handle,
150 pos, to_read, buf, &read_this_time,
151 freepage, freelen);
152 if (error) {
153 error = -EIO; /* NW errno -> Linux errno */
154 break;
155 }
156 pos += read_this_time;
157 buf += read_this_time;
158 already_read += read_this_time;
159
160 if (read_this_time != to_read) {
161 break;
162 }
163 }
164 vfree(freepage);
165
166 *ppos = pos;
167
168 file_accessed(file);
169
170 ncp_dbg(1, "exit %pd2\n", dentry);
171 outrel:
172 ncp_inode_close(inode);
173 return already_read ? already_read : error;
174 }
175
176 static ssize_t
ncp_file_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)177 ncp_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
178 {
179 struct dentry *dentry = file->f_path.dentry;
180 struct inode *inode = dentry->d_inode;
181 size_t already_written = 0;
182 off_t pos;
183 size_t bufsize;
184 int errno;
185 void* bouncebuffer;
186
187 ncp_dbg(1, "enter %pd2\n", dentry);
188 if ((ssize_t) count < 0)
189 return -EINVAL;
190 pos = *ppos;
191 if (file->f_flags & O_APPEND) {
192 pos = i_size_read(inode);
193 }
194
195 if (pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
196 if (pos >= MAX_NON_LFS) {
197 return -EFBIG;
198 }
199 if (count > MAX_NON_LFS - (u32)pos) {
200 count = MAX_NON_LFS - (u32)pos;
201 }
202 }
203 if (pos >= inode->i_sb->s_maxbytes) {
204 if (count || pos > inode->i_sb->s_maxbytes) {
205 return -EFBIG;
206 }
207 }
208 if (pos + count > inode->i_sb->s_maxbytes) {
209 count = inode->i_sb->s_maxbytes - pos;
210 }
211
212 if (!count)
213 return 0;
214 errno = ncp_make_open(inode, O_WRONLY);
215 if (errno) {
216 ncp_dbg(1, "open failed, error=%d\n", errno);
217 return errno;
218 }
219 bufsize = NCP_SERVER(inode)->buffer_size;
220
221 already_written = 0;
222
223 errno = file_update_time(file);
224 if (errno)
225 goto outrel;
226
227 bouncebuffer = vmalloc(bufsize);
228 if (!bouncebuffer) {
229 errno = -EIO; /* -ENOMEM */
230 goto outrel;
231 }
232 while (already_written < count) {
233 int written_this_time;
234 size_t to_write = min_t(unsigned int,
235 bufsize - (pos % bufsize),
236 count - already_written);
237
238 if (copy_from_user(bouncebuffer, buf, to_write)) {
239 errno = -EFAULT;
240 break;
241 }
242 if (ncp_write_kernel(NCP_SERVER(inode),
243 NCP_FINFO(inode)->file_handle,
244 pos, to_write, bouncebuffer, &written_this_time) != 0) {
245 errno = -EIO;
246 break;
247 }
248 pos += written_this_time;
249 buf += written_this_time;
250 already_written += written_this_time;
251
252 if (written_this_time != to_write) {
253 break;
254 }
255 }
256 vfree(bouncebuffer);
257
258 *ppos = pos;
259
260 if (pos > i_size_read(inode)) {
261 mutex_lock(&inode->i_mutex);
262 if (pos > i_size_read(inode))
263 i_size_write(inode, pos);
264 mutex_unlock(&inode->i_mutex);
265 }
266 ncp_dbg(1, "exit %pd2\n", dentry);
267 outrel:
268 ncp_inode_close(inode);
269 return already_written ? already_written : errno;
270 }
271
ncp_release(struct inode * inode,struct file * file)272 static int ncp_release(struct inode *inode, struct file *file) {
273 if (ncp_make_closed(inode)) {
274 ncp_dbg(1, "failed to close\n");
275 }
276 return 0;
277 }
278
279 const struct file_operations ncp_file_operations =
280 {
281 .llseek = generic_file_llseek,
282 .read = ncp_file_read,
283 .write = ncp_file_write,
284 .unlocked_ioctl = ncp_ioctl,
285 #ifdef CONFIG_COMPAT
286 .compat_ioctl = ncp_compat_ioctl,
287 #endif
288 .mmap = ncp_mmap,
289 .release = ncp_release,
290 .fsync = ncp_fsync,
291 };
292
293 const struct inode_operations ncp_file_inode_operations =
294 {
295 .setattr = ncp_notify_change,
296 };
297