xref: /linux/fs/hostfs/hostfs_user.c (revision 561add0da6d3d07c9bccb0832fb6ed5619167d26)
1 /*
2  * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3  * Licensed under the GPL
4  */
5 
6 #include <stdio.h>
7 #include <stddef.h>
8 #include <unistd.h>
9 #include <dirent.h>
10 #include <errno.h>
11 #include <fcntl.h>
12 #include <string.h>
13 #include <sys/stat.h>
14 #include <sys/time.h>
15 #include <sys/types.h>
16 #include <sys/vfs.h>
17 #include <sys/syscall.h>
18 #include "hostfs.h"
19 #include <utime.h>
20 
21 static void stat64_to_hostfs(const struct stat64 *buf, struct hostfs_stat *p)
22 {
23 	p->ino = buf->st_ino;
24 	p->mode = buf->st_mode;
25 	p->nlink = buf->st_nlink;
26 	p->uid = buf->st_uid;
27 	p->gid = buf->st_gid;
28 	p->size = buf->st_size;
29 	p->atime.tv_sec = buf->st_atime;
30 	p->atime.tv_nsec = 0;
31 	p->ctime.tv_sec = buf->st_ctime;
32 	p->ctime.tv_nsec = 0;
33 	p->mtime.tv_sec = buf->st_mtime;
34 	p->mtime.tv_nsec = 0;
35 	p->blksize = buf->st_blksize;
36 	p->blocks = buf->st_blocks;
37 	p->maj = os_major(buf->st_rdev);
38 	p->min = os_minor(buf->st_rdev);
39 	p->dev = buf->st_dev;
40 }
41 
42 int stat_file(const char *path, struct hostfs_stat *p, int fd)
43 {
44 	struct stat64 buf;
45 
46 	if (fd >= 0) {
47 		if (fstat64(fd, &buf) < 0)
48 			return -errno;
49 	} else if (lstat64(path, &buf) < 0) {
50 		return -errno;
51 	}
52 	stat64_to_hostfs(&buf, p);
53 	return 0;
54 }
55 
56 int access_file(char *path, int r, int w, int x)
57 {
58 	int mode = 0;
59 
60 	if (r)
61 		mode = R_OK;
62 	if (w)
63 		mode |= W_OK;
64 	if (x)
65 		mode |= X_OK;
66 	if (access(path, mode) != 0)
67 		return -errno;
68 	else return 0;
69 }
70 
71 int open_file(char *path, int r, int w, int append)
72 {
73 	int mode = 0, fd;
74 
75 	if (r && !w)
76 		mode = O_RDONLY;
77 	else if (!r && w)
78 		mode = O_WRONLY;
79 	else if (r && w)
80 		mode = O_RDWR;
81 	else panic("Impossible mode in open_file");
82 
83 	if (append)
84 		mode |= O_APPEND;
85 	fd = open64(path, mode);
86 	if (fd < 0)
87 		return -errno;
88 	else return fd;
89 }
90 
91 void *open_dir(char *path, int *err_out)
92 {
93 	DIR *dir;
94 
95 	dir = opendir(path);
96 	*err_out = errno;
97 
98 	return dir;
99 }
100 
101 void seek_dir(void *stream, unsigned long long pos)
102 {
103 	DIR *dir = stream;
104 
105 	seekdir(dir, pos);
106 }
107 
108 char *read_dir(void *stream, unsigned long long *pos_out,
109 	       unsigned long long *ino_out, int *len_out,
110 	       unsigned int *type_out)
111 {
112 	DIR *dir = stream;
113 	struct dirent *ent;
114 
115 	ent = readdir(dir);
116 	if (ent == NULL)
117 		return NULL;
118 	*len_out = strlen(ent->d_name);
119 	*ino_out = ent->d_ino;
120 	*type_out = ent->d_type;
121 	*pos_out = ent->d_off;
122 	return ent->d_name;
123 }
124 
125 int read_file(int fd, unsigned long long *offset, char *buf, int len)
126 {
127 	int n;
128 
129 	n = pread64(fd, buf, len, *offset);
130 	if (n < 0)
131 		return -errno;
132 	*offset += n;
133 	return n;
134 }
135 
136 int write_file(int fd, unsigned long long *offset, const char *buf, int len)
137 {
138 	int n;
139 
140 	n = pwrite64(fd, buf, len, *offset);
141 	if (n < 0)
142 		return -errno;
143 	*offset += n;
144 	return n;
145 }
146 
147 int lseek_file(int fd, long long offset, int whence)
148 {
149 	int ret;
150 
151 	ret = lseek64(fd, offset, whence);
152 	if (ret < 0)
153 		return -errno;
154 	return 0;
155 }
156 
157 int fsync_file(int fd, int datasync)
158 {
159 	int ret;
160 	if (datasync)
161 		ret = fdatasync(fd);
162 	else
163 		ret = fsync(fd);
164 
165 	if (ret < 0)
166 		return -errno;
167 	return 0;
168 }
169 
170 int replace_file(int oldfd, int fd)
171 {
172 	return dup2(oldfd, fd);
173 }
174 
175 void close_file(void *stream)
176 {
177 	close(*((int *) stream));
178 }
179 
180 void close_dir(void *stream)
181 {
182 	closedir(stream);
183 }
184 
185 int file_create(char *name, int mode)
186 {
187 	int fd;
188 
189 	fd = open64(name, O_CREAT | O_RDWR, mode);
190 	if (fd < 0)
191 		return -errno;
192 	return fd;
193 }
194 
195 int set_attr(const char *file, struct hostfs_iattr *attrs, int fd)
196 {
197 	struct hostfs_stat st;
198 	struct timeval times[2];
199 	int err, ma;
200 
201 	if (attrs->ia_valid & HOSTFS_ATTR_MODE) {
202 		if (fd >= 0) {
203 			if (fchmod(fd, attrs->ia_mode) != 0)
204 				return -errno;
205 		} else if (chmod(file, attrs->ia_mode) != 0) {
206 			return -errno;
207 		}
208 	}
209 	if (attrs->ia_valid & HOSTFS_ATTR_UID) {
210 		if (fd >= 0) {
211 			if (fchown(fd, attrs->ia_uid, -1))
212 				return -errno;
213 		} else if (chown(file, attrs->ia_uid, -1)) {
214 			return -errno;
215 		}
216 	}
217 	if (attrs->ia_valid & HOSTFS_ATTR_GID) {
218 		if (fd >= 0) {
219 			if (fchown(fd, -1, attrs->ia_gid))
220 				return -errno;
221 		} else if (chown(file, -1, attrs->ia_gid)) {
222 			return -errno;
223 		}
224 	}
225 	if (attrs->ia_valid & HOSTFS_ATTR_SIZE) {
226 		if (fd >= 0) {
227 			if (ftruncate(fd, attrs->ia_size))
228 				return -errno;
229 		} else if (truncate(file, attrs->ia_size)) {
230 			return -errno;
231 		}
232 	}
233 
234 	/*
235 	 * Update accessed and/or modified time, in two parts: first set
236 	 * times according to the changes to perform, and then call futimes()
237 	 * or utimes() to apply them.
238 	 */
239 	ma = (HOSTFS_ATTR_ATIME_SET | HOSTFS_ATTR_MTIME_SET);
240 	if (attrs->ia_valid & ma) {
241 		err = stat_file(file, &st, fd);
242 		if (err != 0)
243 			return err;
244 
245 		times[0].tv_sec = st.atime.tv_sec;
246 		times[0].tv_usec = st.atime.tv_nsec / 1000;
247 		times[1].tv_sec = st.mtime.tv_sec;
248 		times[1].tv_usec = st.mtime.tv_nsec / 1000;
249 
250 		if (attrs->ia_valid & HOSTFS_ATTR_ATIME_SET) {
251 			times[0].tv_sec = attrs->ia_atime.tv_sec;
252 			times[0].tv_usec = attrs->ia_atime.tv_nsec / 1000;
253 		}
254 		if (attrs->ia_valid & HOSTFS_ATTR_MTIME_SET) {
255 			times[1].tv_sec = attrs->ia_mtime.tv_sec;
256 			times[1].tv_usec = attrs->ia_mtime.tv_nsec / 1000;
257 		}
258 
259 		if (fd >= 0) {
260 			if (futimes(fd, times) != 0)
261 				return -errno;
262 		} else if (utimes(file, times) != 0) {
263 			return -errno;
264 		}
265 	}
266 
267 	/* Note: ctime is not handled */
268 	if (attrs->ia_valid & (HOSTFS_ATTR_ATIME | HOSTFS_ATTR_MTIME)) {
269 		err = stat_file(file, &st, fd);
270 		attrs->ia_atime = st.atime;
271 		attrs->ia_mtime = st.mtime;
272 		if (err != 0)
273 			return err;
274 	}
275 	return 0;
276 }
277 
278 int make_symlink(const char *from, const char *to)
279 {
280 	int err;
281 
282 	err = symlink(to, from);
283 	if (err)
284 		return -errno;
285 	return 0;
286 }
287 
288 int unlink_file(const char *file)
289 {
290 	int err;
291 
292 	err = unlink(file);
293 	if (err)
294 		return -errno;
295 	return 0;
296 }
297 
298 int do_mkdir(const char *file, int mode)
299 {
300 	int err;
301 
302 	err = mkdir(file, mode);
303 	if (err)
304 		return -errno;
305 	return 0;
306 }
307 
308 int hostfs_do_rmdir(const char *file)
309 {
310 	int err;
311 
312 	err = rmdir(file);
313 	if (err)
314 		return -errno;
315 	return 0;
316 }
317 
318 int do_mknod(const char *file, int mode, unsigned int major, unsigned int minor)
319 {
320 	int err;
321 
322 	err = mknod(file, mode, os_makedev(major, minor));
323 	if (err)
324 		return -errno;
325 	return 0;
326 }
327 
328 int link_file(const char *to, const char *from)
329 {
330 	int err;
331 
332 	err = link(to, from);
333 	if (err)
334 		return -errno;
335 	return 0;
336 }
337 
338 int hostfs_do_readlink(char *file, char *buf, int size)
339 {
340 	int n;
341 
342 	n = readlink(file, buf, size);
343 	if (n < 0)
344 		return -errno;
345 	if (n < size)
346 		buf[n] = '\0';
347 	return n;
348 }
349 
350 int rename_file(char *from, char *to)
351 {
352 	int err;
353 
354 	err = rename(from, to);
355 	if (err < 0)
356 		return -errno;
357 	return 0;
358 }
359 
360 int rename2_file(char *from, char *to, unsigned int flags)
361 {
362 	int err;
363 
364 #ifndef SYS_renameat2
365 #  ifdef __x86_64__
366 #    define SYS_renameat2 316
367 #  endif
368 #  ifdef __i386__
369 #    define SYS_renameat2 353
370 #  endif
371 #endif
372 
373 #ifdef SYS_renameat2
374 	err = syscall(SYS_renameat2, AT_FDCWD, from, AT_FDCWD, to, flags);
375 	if (err < 0) {
376 		if (errno != ENOSYS)
377 			return -errno;
378 		else
379 			return -EINVAL;
380 	}
381 	return 0;
382 #else
383 	return -EINVAL;
384 #endif
385 }
386 
387 int do_statfs(char *root, long *bsize_out, long long *blocks_out,
388 	      long long *bfree_out, long long *bavail_out,
389 	      long long *files_out, long long *ffree_out,
390 	      void *fsid_out, int fsid_size, long *namelen_out)
391 {
392 	struct statfs64 buf;
393 	int err;
394 
395 	err = statfs64(root, &buf);
396 	if (err < 0)
397 		return -errno;
398 
399 	*bsize_out = buf.f_bsize;
400 	*blocks_out = buf.f_blocks;
401 	*bfree_out = buf.f_bfree;
402 	*bavail_out = buf.f_bavail;
403 	*files_out = buf.f_files;
404 	*ffree_out = buf.f_ffree;
405 	memcpy(fsid_out, &buf.f_fsid,
406 	       sizeof(buf.f_fsid) > fsid_size ? fsid_size :
407 	       sizeof(buf.f_fsid));
408 	*namelen_out = buf.f_namelen;
409 
410 	return 0;
411 }
412