hostfs_user.c

  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
 21static void statx_to_hostfs(const struct statx *buf, struct hostfs_stat *p)
 22{
 23	p->ino = buf->stx_ino;
 24	p->mode = buf->stx_mode;
 25	p->nlink = buf->stx_nlink;
 26	p->uid = buf->stx_uid;
 27	p->gid = buf->stx_gid;
 28	p->size = buf->stx_size;
 29	p->atime.tv_sec = buf->stx_atime.tv_sec;
 30	p->atime.tv_nsec = buf->stx_atime.tv_nsec;
 31	p->ctime.tv_sec = buf->stx_ctime.tv_sec;
 32	p->ctime.tv_nsec = buf->stx_ctime.tv_nsec;
 33	p->mtime.tv_sec = buf->stx_mtime.tv_sec;
 34	p->mtime.tv_nsec = buf->stx_mtime.tv_nsec;
 35	if (buf->stx_mask & STATX_BTIME) {
 36		p->btime.tv_sec = buf->stx_btime.tv_sec;
 37		p->btime.tv_nsec = buf->stx_btime.tv_nsec;
 38	} else {
 39		memset(&p->btime, 0, sizeof(p->btime));
 40	}
 41	p->blksize = buf->stx_blksize;
 42	p->blocks = buf->stx_blocks;
 43	p->rdev.maj = buf->stx_rdev_major;
 44	p->rdev.min = buf->stx_rdev_minor;
 45	p->dev.maj = buf->stx_dev_major;
 46	p->dev.min = buf->stx_dev_minor;
 47}
 48
 49int stat_file(const char *path, struct hostfs_stat *p, int fd)
 50{
 51	struct statx buf;
 52	int flags = AT_SYMLINK_NOFOLLOW;
 53
 54	if (fd >= 0) {
 55		flags |= AT_EMPTY_PATH;
 56		path = "";
 57	}
 58
 59	if ((statx(fd, path, flags, STATX_BASIC_STATS | STATX_BTIME, &buf)) < 0)
 60		return -errno;
 61
 62	statx_to_hostfs(&buf, p);
 63	return 0;
 64}
 65
 66int access_file(char *path, int r, int w, int x)
 67{
 68	int mode = 0;
 69
 70	if (r)
 71		mode = R_OK;
 72	if (w)
 73		mode |= W_OK;
 74	if (x)
 75		mode |= X_OK;
 76	if (access(path, mode) != 0)
 77		return -errno;
 78	else return 0;
 79}
 80
 81int open_file(char *path, int r, int w, int append)
 82{
 83	int mode = 0, fd;
 84
 85	if (r && !w)
 86		mode = O_RDONLY;
 87	else if (!r && w)
 88		mode = O_WRONLY;
 89	else if (r && w)
 90		mode = O_RDWR;
 91	else panic("Impossible mode in open_file");
 92
 93	if (append)
 94		mode |= O_APPEND;
 95	fd = open64(path, mode);
 96	if (fd < 0)
 97		return -errno;
 98	else return fd;
 99}
100
101void *open_dir(char *path, int *err_out)
102{
103	DIR *dir;
104
105	dir = opendir(path);
106	*err_out = errno;
107
108	return dir;
109}
110
111void seek_dir(void *stream, unsigned long long pos)
112{
113	DIR *dir = stream;
114
115	seekdir(dir, pos);
116}
117
118char *read_dir(void *stream, unsigned long long *pos_out,
119	       unsigned long long *ino_out, int *len_out,
120	       unsigned int *type_out)
121{
122	DIR *dir = stream;
123	struct dirent *ent;
124
125	ent = readdir(dir);
126	if (ent == NULL)
127		return NULL;
128	*len_out = strlen(ent->d_name);
129	*ino_out = ent->d_ino;
130	*type_out = ent->d_type;
131	*pos_out = ent->d_off;
132	return ent->d_name;
133}
134
135int read_file(int fd, unsigned long long *offset, char *buf, int len)
136{
137	int n;
138
139	n = pread64(fd, buf, len, *offset);
140	if (n < 0)
141		return -errno;
142	*offset += n;
143	return n;
144}
145
146int write_file(int fd, unsigned long long *offset, const char *buf, int len)
147{
148	int n;
149
150	n = pwrite64(fd, buf, len, *offset);
151	if (n < 0)
152		return -errno;
153	*offset += n;
154	return n;
155}
156
157int lseek_file(int fd, long long offset, int whence)
158{
159	int ret;
160
161	ret = lseek64(fd, offset, whence);
162	if (ret < 0)
163		return -errno;
164	return 0;
165}
166
167int fsync_file(int fd, int datasync)
168{
169	int ret;
170	if (datasync)
171		ret = fdatasync(fd);
172	else
173		ret = fsync(fd);
174
175	if (ret < 0)
176		return -errno;
177	return 0;
178}
179
180int replace_file(int oldfd, int fd)
181{
182	return dup2(oldfd, fd);
183}
184
185void close_file(void *stream)
186{
187	close(*((int *) stream));
188}
189
190void close_dir(void *stream)
191{
192	closedir(stream);
193}
194
195int file_create(char *name, int mode)
196{
197	int fd;
198
199	fd = open64(name, O_CREAT | O_RDWR, mode);
200	if (fd < 0)
201		return -errno;
202	return fd;
203}
204
205int set_attr(const char *file, struct hostfs_iattr *attrs, int fd)
206{
207	struct hostfs_stat st;
208	struct timeval times[2];
209	int err, ma;
210
211	if (attrs->ia_valid & HOSTFS_ATTR_MODE) {
212		if (fd >= 0) {
213			if (fchmod(fd, attrs->ia_mode) != 0)
214				return -errno;
215		} else if (chmod(file, attrs->ia_mode) != 0) {
216			return -errno;
217		}
218	}
219	if (attrs->ia_valid & HOSTFS_ATTR_UID) {
220		if (fd >= 0) {
221			if (fchown(fd, attrs->ia_uid, -1))
222				return -errno;
223		} else if (chown(file, attrs->ia_uid, -1)) {
224			return -errno;
225		}
226	}
227	if (attrs->ia_valid & HOSTFS_ATTR_GID) {
228		if (fd >= 0) {
229			if (fchown(fd, -1, attrs->ia_gid))
230				return -errno;
231		} else if (chown(file, -1, attrs->ia_gid)) {
232			return -errno;
233		}
234	}
235	if (attrs->ia_valid & HOSTFS_ATTR_SIZE) {
236		if (fd >= 0) {
237			if (ftruncate(fd, attrs->ia_size))
238				return -errno;
239		} else if (truncate(file, attrs->ia_size)) {
240			return -errno;
241		}
242	}
243
244	/*
245	 * Update accessed and/or modified time, in two parts: first set
246	 * times according to the changes to perform, and then call futimes()
247	 * or utimes() to apply them.
248	 */
249	ma = (HOSTFS_ATTR_ATIME_SET | HOSTFS_ATTR_MTIME_SET);
250	if (attrs->ia_valid & ma) {
251		err = stat_file(file, &st, fd);
252		if (err != 0)
253			return err;
254
255		times[0].tv_sec = st.atime.tv_sec;
256		times[0].tv_usec = st.atime.tv_nsec / 1000;
257		times[1].tv_sec = st.mtime.tv_sec;
258		times[1].tv_usec = st.mtime.tv_nsec / 1000;
259
260		if (attrs->ia_valid & HOSTFS_ATTR_ATIME_SET) {
261			times[0].tv_sec = attrs->ia_atime.tv_sec;
262			times[0].tv_usec = attrs->ia_atime.tv_nsec / 1000;
263		}
264		if (attrs->ia_valid & HOSTFS_ATTR_MTIME_SET) {
265			times[1].tv_sec = attrs->ia_mtime.tv_sec;
266			times[1].tv_usec = attrs->ia_mtime.tv_nsec / 1000;
267		}
268
269		if (fd >= 0) {
270			if (futimes(fd, times) != 0)
271				return -errno;
272		} else if (utimes(file, times) != 0) {
273			return -errno;
274		}
275	}
276
277	/* Note: ctime is not handled */
278	if (attrs->ia_valid & (HOSTFS_ATTR_ATIME | HOSTFS_ATTR_MTIME)) {
279		err = stat_file(file, &st, fd);
280		attrs->ia_atime = st.atime;
281		attrs->ia_mtime = st.mtime;
282		if (err != 0)
283			return err;
284	}
285	return 0;
286}
287
288int make_symlink(const char *from, const char *to)
289{
290	int err;
291
292	err = symlink(to, from);
293	if (err)
294		return -errno;
295	return 0;
296}
297
298int unlink_file(const char *file)
299{
300	int err;
301
302	err = unlink(file);
303	if (err)
304		return -errno;
305	return 0;
306}
307
308int do_mkdir(const char *file, int mode)
309{
310	int err;
311
312	err = mkdir(file, mode);
313	if (err)
314		return -errno;
315	return 0;
316}
317
318int hostfs_do_rmdir(const char *file)
319{
320	int err;
321
322	err = rmdir(file);
323	if (err)
324		return -errno;
325	return 0;
326}
327
328int do_mknod(const char *file, int mode, unsigned int major, unsigned int minor)
329{
330	int err;
331
332	err = mknod(file, mode, os_makedev(major, minor));
333	if (err)
334		return -errno;
335	return 0;
336}
337
338int link_file(const char *to, const char *from)
339{
340	int err;
341
342	err = link(to, from);
343	if (err)
344		return -errno;
345	return 0;
346}
347
348int hostfs_do_readlink(char *file, char *buf, int size)
349{
350	int n;
351
352	n = readlink(file, buf, size);
353	if (n < 0)
354		return -errno;
355	if (n < size)
356		buf[n] = '\0';
357	return n;
358}
359
360int rename_file(char *from, char *to)
361{
362	int err;
363
364	err = rename(from, to);
365	if (err < 0)
366		return -errno;
367	return 0;
368}
369
370int rename2_file(char *from, char *to, unsigned int flags)
371{
372	int err;
373
374#ifndef SYS_renameat2
375#  ifdef __x86_64__
376#    define SYS_renameat2 316
377#  endif
378#  ifdef __i386__
379#    define SYS_renameat2 353
380#  endif
381#endif
382
383#ifdef SYS_renameat2
384	err = syscall(SYS_renameat2, AT_FDCWD, from, AT_FDCWD, to, flags);
385	if (err < 0) {
386		if (errno != ENOSYS)
387			return -errno;
388		else
389			return -EINVAL;
390	}
391	return 0;
392#else
393	return -EINVAL;
394#endif
395}
396
397int do_statfs(char *root, long *bsize_out, long long *blocks_out,
398	      long long *bfree_out, long long *bavail_out,
399	      long long *files_out, long long *ffree_out,
400	      void *fsid_out, int fsid_size, long *namelen_out)
401{
402	struct statfs64 buf;
403	int err;
404
405	err = statfs64(root, &buf);
406	if (err < 0)
407		return -errno;
408
409	*bsize_out = buf.f_bsize;
410	*blocks_out = buf.f_blocks;
411	*bfree_out = buf.f_bfree;
412	*bavail_out = buf.f_bavail;
413	*files_out = buf.f_files;
414	*ffree_out = buf.f_ffree;
415	memcpy(fsid_out, &buf.f_fsid,
416	       sizeof(buf.f_fsid) > fsid_size ? fsid_size :
417	       sizeof(buf.f_fsid));
418	*namelen_out = buf.f_namelen;
419
420	return 0;
421}