xref: /linux/fs/hostfs/hostfs_user.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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 }
40 
41 int stat_file(const char *path, struct hostfs_stat *p, int fd)
42 {
43 	struct stat64 buf;
44 
45 	if (fd >= 0) {
46 		if (fstat64(fd, &buf) < 0)
47 			return -errno;
48 	} else if (lstat64(path, &buf) < 0) {
49 		return -errno;
50 	}
51 	stat64_to_hostfs(&buf, p);
52 	return 0;
53 }
54 
55 int access_file(char *path, int r, int w, int x)
56 {
57 	int mode = 0;
58 
59 	if (r)
60 		mode = R_OK;
61 	if (w)
62 		mode |= W_OK;
63 	if (x)
64 		mode |= X_OK;
65 	if (access(path, mode) != 0)
66 		return -errno;
67 	else return 0;
68 }
69 
70 int open_file(char *path, int r, int w, int append)
71 {
72 	int mode = 0, fd;
73 
74 	if (r && !w)
75 		mode = O_RDONLY;
76 	else if (!r && w)
77 		mode = O_WRONLY;
78 	else if (r && w)
79 		mode = O_RDWR;
80 	else panic("Impossible mode in open_file");
81 
82 	if (append)
83 		mode |= O_APPEND;
84 	fd = open64(path, mode);
85 	if (fd < 0)
86 		return -errno;
87 	else return fd;
88 }
89 
90 void *open_dir(char *path, int *err_out)
91 {
92 	DIR *dir;
93 
94 	dir = opendir(path);
95 	*err_out = errno;
96 
97 	return dir;
98 }
99 
100 void seek_dir(void *stream, unsigned long long pos)
101 {
102 	DIR *dir = stream;
103 
104 	seekdir(dir, pos);
105 }
106 
107 char *read_dir(void *stream, unsigned long long *pos_out,
108 	       unsigned long long *ino_out, int *len_out,
109 	       unsigned int *type_out)
110 {
111 	DIR *dir = stream;
112 	struct dirent *ent;
113 
114 	ent = readdir(dir);
115 	if (ent == NULL)
116 		return NULL;
117 	*len_out = strlen(ent->d_name);
118 	*ino_out = ent->d_ino;
119 	*type_out = ent->d_type;
120 	*pos_out = ent->d_off;
121 	return ent->d_name;
122 }
123 
124 int read_file(int fd, unsigned long long *offset, char *buf, int len)
125 {
126 	int n;
127 
128 	n = pread64(fd, buf, len, *offset);
129 	if (n < 0)
130 		return -errno;
131 	*offset += n;
132 	return n;
133 }
134 
135 int write_file(int fd, unsigned long long *offset, const char *buf, int len)
136 {
137 	int n;
138 
139 	n = pwrite64(fd, buf, len, *offset);
140 	if (n < 0)
141 		return -errno;
142 	*offset += n;
143 	return n;
144 }
145 
146 int lseek_file(int fd, long long offset, int whence)
147 {
148 	int ret;
149 
150 	ret = lseek64(fd, offset, whence);
151 	if (ret < 0)
152 		return -errno;
153 	return 0;
154 }
155 
156 int fsync_file(int fd, int datasync)
157 {
158 	int ret;
159 	if (datasync)
160 		ret = fdatasync(fd);
161 	else
162 		ret = fsync(fd);
163 
164 	if (ret < 0)
165 		return -errno;
166 	return 0;
167 }
168 
169 int replace_file(int oldfd, int fd)
170 {
171 	return dup2(oldfd, fd);
172 }
173 
174 void close_file(void *stream)
175 {
176 	close(*((int *) stream));
177 }
178 
179 void close_dir(void *stream)
180 {
181 	closedir(stream);
182 }
183 
184 int file_create(char *name, int mode)
185 {
186 	int fd;
187 
188 	fd = open64(name, O_CREAT | O_RDWR, mode);
189 	if (fd < 0)
190 		return -errno;
191 	return fd;
192 }
193 
194 int set_attr(const char *file, struct hostfs_iattr *attrs, int fd)
195 {
196 	struct hostfs_stat st;
197 	struct timeval times[2];
198 	int err, ma;
199 
200 	if (attrs->ia_valid & HOSTFS_ATTR_MODE) {
201 		if (fd >= 0) {
202 			if (fchmod(fd, attrs->ia_mode) != 0)
203 				return -errno;
204 		} else if (chmod(file, attrs->ia_mode) != 0) {
205 			return -errno;
206 		}
207 	}
208 	if (attrs->ia_valid & HOSTFS_ATTR_UID) {
209 		if (fd >= 0) {
210 			if (fchown(fd, attrs->ia_uid, -1))
211 				return -errno;
212 		} else if (chown(file, attrs->ia_uid, -1)) {
213 			return -errno;
214 		}
215 	}
216 	if (attrs->ia_valid & HOSTFS_ATTR_GID) {
217 		if (fd >= 0) {
218 			if (fchown(fd, -1, attrs->ia_gid))
219 				return -errno;
220 		} else if (chown(file, -1, attrs->ia_gid)) {
221 			return -errno;
222 		}
223 	}
224 	if (attrs->ia_valid & HOSTFS_ATTR_SIZE) {
225 		if (fd >= 0) {
226 			if (ftruncate(fd, attrs->ia_size))
227 				return -errno;
228 		} else if (truncate(file, attrs->ia_size)) {
229 			return -errno;
230 		}
231 	}
232 
233 	/*
234 	 * Update accessed and/or modified time, in two parts: first set
235 	 * times according to the changes to perform, and then call futimes()
236 	 * or utimes() to apply them.
237 	 */
238 	ma = (HOSTFS_ATTR_ATIME_SET | HOSTFS_ATTR_MTIME_SET);
239 	if (attrs->ia_valid & ma) {
240 		err = stat_file(file, &st, fd);
241 		if (err != 0)
242 			return err;
243 
244 		times[0].tv_sec = st.atime.tv_sec;
245 		times[0].tv_usec = st.atime.tv_nsec / 1000;
246 		times[1].tv_sec = st.mtime.tv_sec;
247 		times[1].tv_usec = st.mtime.tv_nsec / 1000;
248 
249 		if (attrs->ia_valid & HOSTFS_ATTR_ATIME_SET) {
250 			times[0].tv_sec = attrs->ia_atime.tv_sec;
251 			times[0].tv_usec = attrs->ia_atime.tv_nsec / 1000;
252 		}
253 		if (attrs->ia_valid & HOSTFS_ATTR_MTIME_SET) {
254 			times[1].tv_sec = attrs->ia_mtime.tv_sec;
255 			times[1].tv_usec = attrs->ia_mtime.tv_nsec / 1000;
256 		}
257 
258 		if (fd >= 0) {
259 			if (futimes(fd, times) != 0)
260 				return -errno;
261 		} else if (utimes(file, times) != 0) {
262 			return -errno;
263 		}
264 	}
265 
266 	/* Note: ctime is not handled */
267 	if (attrs->ia_valid & (HOSTFS_ATTR_ATIME | HOSTFS_ATTR_MTIME)) {
268 		err = stat_file(file, &st, fd);
269 		attrs->ia_atime = st.atime;
270 		attrs->ia_mtime = st.mtime;
271 		if (err != 0)
272 			return err;
273 	}
274 	return 0;
275 }
276 
277 int make_symlink(const char *from, const char *to)
278 {
279 	int err;
280 
281 	err = symlink(to, from);
282 	if (err)
283 		return -errno;
284 	return 0;
285 }
286 
287 int unlink_file(const char *file)
288 {
289 	int err;
290 
291 	err = unlink(file);
292 	if (err)
293 		return -errno;
294 	return 0;
295 }
296 
297 int do_mkdir(const char *file, int mode)
298 {
299 	int err;
300 
301 	err = mkdir(file, mode);
302 	if (err)
303 		return -errno;
304 	return 0;
305 }
306 
307 int do_rmdir(const char *file)
308 {
309 	int err;
310 
311 	err = rmdir(file);
312 	if (err)
313 		return -errno;
314 	return 0;
315 }
316 
317 int do_mknod(const char *file, int mode, unsigned int major, unsigned int minor)
318 {
319 	int err;
320 
321 	err = mknod(file, mode, os_makedev(major, minor));
322 	if (err)
323 		return -errno;
324 	return 0;
325 }
326 
327 int link_file(const char *to, const char *from)
328 {
329 	int err;
330 
331 	err = link(to, from);
332 	if (err)
333 		return -errno;
334 	return 0;
335 }
336 
337 int hostfs_do_readlink(char *file, char *buf, int size)
338 {
339 	int n;
340 
341 	n = readlink(file, buf, size);
342 	if (n < 0)
343 		return -errno;
344 	if (n < size)
345 		buf[n] = '\0';
346 	return n;
347 }
348 
349 int rename_file(char *from, char *to)
350 {
351 	int err;
352 
353 	err = rename(from, to);
354 	if (err < 0)
355 		return -errno;
356 	return 0;
357 }
358 
359 int rename2_file(char *from, char *to, unsigned int flags)
360 {
361 	int err;
362 
363 #ifndef SYS_renameat2
364 #  ifdef __x86_64__
365 #    define SYS_renameat2 316
366 #  endif
367 #  ifdef __i386__
368 #    define SYS_renameat2 353
369 #  endif
370 #endif
371 
372 #ifdef SYS_renameat2
373 	err = syscall(SYS_renameat2, AT_FDCWD, from, AT_FDCWD, to, flags);
374 	if (err < 0) {
375 		if (errno != ENOSYS)
376 			return -errno;
377 		else
378 			return -EINVAL;
379 	}
380 	return 0;
381 #else
382 	return -EINVAL;
383 #endif
384 }
385 
386 int do_statfs(char *root, long *bsize_out, long long *blocks_out,
387 	      long long *bfree_out, long long *bavail_out,
388 	      long long *files_out, long long *ffree_out,
389 	      void *fsid_out, int fsid_size, long *namelen_out)
390 {
391 	struct statfs64 buf;
392 	int err;
393 
394 	err = statfs64(root, &buf);
395 	if (err < 0)
396 		return -errno;
397 
398 	*bsize_out = buf.f_bsize;
399 	*blocks_out = buf.f_blocks;
400 	*bfree_out = buf.f_bfree;
401 	*bavail_out = buf.f_bavail;
402 	*files_out = buf.f_files;
403 	*ffree_out = buf.f_ffree;
404 	memcpy(fsid_out, &buf.f_fsid,
405 	       sizeof(buf.f_fsid) > fsid_size ? fsid_size :
406 	       sizeof(buf.f_fsid));
407 	*namelen_out = buf.f_namelen;
408 
409 	return 0;
410 }
411