[mirror_ubuntu-artful-kernel.git] / fs / stat.c

/*
 *  linux/fs/stat.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#include <linux/export.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/highuid.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/pagemap.h>

#include <asm/uaccess.h>
#include <asm/unistd.h>

void generic_fillattr(struct inode *inode, struct kstat *stat)
{
	stat->dev = inode->i_sb->s_dev;
	stat->ino = inode->i_ino;
	stat->mode = inode->i_mode;
	stat->nlink = inode->i_nlink;
	stat->uid = inode->i_uid;
	stat->gid = inode->i_gid;
	stat->rdev = inode->i_rdev;
	stat->size = i_size_read(inode);
	stat->atime = inode->i_atime;
	stat->mtime = inode->i_mtime;
	stat->ctime = inode->i_ctime;
	stat->blksize = (1 << inode->i_blkbits);
	stat->blocks = inode->i_blocks;
}

EXPORT_SYMBOL(generic_fillattr);

int vfs_getattr(struct path *path, struct kstat *stat)
{
	struct inode *inode = path->dentry->d_inode;
	int retval;

	retval = security_inode_getattr(path->mnt, path->dentry);
	if (retval)
		return retval;

	if (inode->i_op->getattr)
		return inode->i_op->getattr(path->mnt, path->dentry, stat);

	generic_fillattr(inode, stat);
	return 0;
}

EXPORT_SYMBOL(vfs_getattr);

int vfs_fstat(unsigned int fd, struct kstat *stat)
{
	struct fd f = fdget_raw(fd);
	int error = -EBADF;

	if (f.file) {
		error = vfs_getattr(&f.file->f_path, stat);
		fdput(f);
	}
	return error;
}
EXPORT_SYMBOL(vfs_fstat);

int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
		int flag)
{
	struct path path;
	int error = -EINVAL;
	unsigned int lookup_flags = 0;

	if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
		      AT_EMPTY_PATH)) != 0)
		goto out;

	if (!(flag & AT_SYMLINK_NOFOLLOW))
		lookup_flags |= LOOKUP_FOLLOW;
	if (flag & AT_EMPTY_PATH)
		lookup_flags |= LOOKUP_EMPTY;
retry:
	error = user_path_at(dfd, filename, lookup_flags, &path);
	if (error)
		goto out;

	error = vfs_getattr(&path, stat);
	path_put(&path);
	if (retry_estale(error, lookup_flags)) {
		lookup_flags |= LOOKUP_REVAL;
		goto retry;
	}
out:
	return error;
}
EXPORT_SYMBOL(vfs_fstatat);

int vfs_stat(const char __user *name, struct kstat *stat)
{
	return vfs_fstatat(AT_FDCWD, name, stat, 0);
}
EXPORT_SYMBOL(vfs_stat);

int vfs_lstat(const char __user *name, struct kstat *stat)
{
	return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
}
EXPORT_SYMBOL(vfs_lstat);


#ifdef __ARCH_WANT_OLD_STAT

/*
 * For backward compatibility?  Maybe this should be moved
 * into arch/i386 instead?
 */
static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf)
{
	static int warncount = 5;
	struct __old_kernel_stat tmp;
	
	if (warncount > 0) {
		warncount--;
		printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
			current->comm);
	} else if (warncount < 0) {
		/* it's laughable, but... */
		warncount = 0;
	}

	memset(&tmp, 0, sizeof(struct __old_kernel_stat));
	tmp.st_dev = old_encode_dev(stat->dev);
	tmp.st_ino = stat->ino;
	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
		return -EOVERFLOW;
	tmp.st_mode = stat->mode;
	tmp.st_nlink = stat->nlink;
	if (tmp.st_nlink != stat->nlink)
		return -EOVERFLOW;
	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
	tmp.st_rdev = old_encode_dev(stat->rdev);
#if BITS_PER_LONG == 32
	if (stat->size > MAX_NON_LFS)
		return -EOVERFLOW;
#endif	
	tmp.st_size = stat->size;
	tmp.st_atime = stat->atime.tv_sec;
	tmp.st_mtime = stat->mtime.tv_sec;
	tmp.st_ctime = stat->ctime.tv_sec;
	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
}

SYSCALL_DEFINE2(stat, const char __user *, filename,
		struct __old_kernel_stat __user *, statbuf)
{
	struct kstat stat;
	int error;

	error = vfs_stat(filename, &stat);
	if (error)
		return error;

	return cp_old_stat(&stat, statbuf);
}

SYSCALL_DEFINE2(lstat, const char __user *, filename,
		struct __old_kernel_stat __user *, statbuf)
{
	struct kstat stat;
	int error;

	error = vfs_lstat(filename, &stat);
	if (error)
		return error;

	return cp_old_stat(&stat, statbuf);
}

SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
{
	struct kstat stat;
	int error = vfs_fstat(fd, &stat);

	if (!error)
		error = cp_old_stat(&stat, statbuf);

	return error;
}

#endif /* __ARCH_WANT_OLD_STAT */

#if BITS_PER_LONG == 32
#  define choose_32_64(a,b) a
#else
#  define choose_32_64(a,b) b
#endif

#define valid_dev(x)  choose_32_64(old_valid_dev,new_valid_dev)(x)
#define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)

#ifndef INIT_STRUCT_STAT_PADDING
#  define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
#endif

static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
{
	struct stat tmp;

	if (!valid_dev(stat->dev) || !valid_dev(stat->rdev))
		return -EOVERFLOW;
#if BITS_PER_LONG == 32
	if (stat->size > MAX_NON_LFS)
		return -EOVERFLOW;
#endif

	INIT_STRUCT_STAT_PADDING(tmp);
	tmp.st_dev = encode_dev(stat->dev);
	tmp.st_ino = stat->ino;
	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
		return -EOVERFLOW;
	tmp.st_mode = stat->mode;
	tmp.st_nlink = stat->nlink;
	if (tmp.st_nlink != stat->nlink)
		return -EOVERFLOW;
	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
	tmp.st_rdev = encode_dev(stat->rdev);
	tmp.st_size = stat->size;
	tmp.st_atime = stat->atime.tv_sec;
	tmp.st_mtime = stat->mtime.tv_sec;
	tmp.st_ctime = stat->ctime.tv_sec;
#ifdef STAT_HAVE_NSEC
	tmp.st_atime_nsec = stat->atime.tv_nsec;
	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
#endif
	tmp.st_blocks = stat->blocks;
	tmp.st_blksize = stat->blksize;
	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
}

SYSCALL_DEFINE2(newstat, const char __user *, filename,
		struct stat __user *, statbuf)
{
	struct kstat stat;
	int error = vfs_stat(filename, &stat);

	if (error)
		return error;
	return cp_new_stat(&stat, statbuf);
}

SYSCALL_DEFINE2(newlstat, const char __user *, filename,
		struct stat __user *, statbuf)
{
	struct kstat stat;
	int error;

	error = vfs_lstat(filename, &stat);
	if (error)
		return error;

	return cp_new_stat(&stat, statbuf);
}

#if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
		struct stat __user *, statbuf, int, flag)
{
	struct kstat stat;
	int error;

	error = vfs_fstatat(dfd, filename, &stat, flag);
	if (error)
		return error;
	return cp_new_stat(&stat, statbuf);
}
#endif

SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
{
	struct kstat stat;
	int error = vfs_fstat(fd, &stat);

	if (!error)
		error = cp_new_stat(&stat, statbuf);

	return error;
}

SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
		char __user *, buf, int, bufsiz)
{
	struct path path;
	int error;
	int empty = 0;
	unsigned int lookup_flags = LOOKUP_EMPTY;

	if (bufsiz <= 0)
		return -EINVAL;

retry:
	error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
	if (!error) {
		struct inode *inode = path.dentry->d_inode;

		error = empty ? -ENOENT : -EINVAL;
		if (inode->i_op->readlink) {
			error = security_inode_readlink(path.dentry);
			if (!error) {
				touch_atime(&path);
				error = inode->i_op->readlink(path.dentry,
							      buf, bufsiz);
			}
		}
		path_put(&path);
		if (retry_estale(error, lookup_flags)) {
			lookup_flags |= LOOKUP_REVAL;
			goto retry;
		}
	}
	return error;
}

SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
		int, bufsiz)
{
	return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
}


/* ---------- LFS-64 ----------- */
#if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)

#ifndef INIT_STRUCT_STAT64_PADDING
#  define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
#endif

static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
{
	struct stat64 tmp;

	INIT_STRUCT_STAT64_PADDING(tmp);
#ifdef CONFIG_MIPS
	/* mips has weird padding, so we don't get 64 bits there */
	if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
		return -EOVERFLOW;
	tmp.st_dev = new_encode_dev(stat->dev);
	tmp.st_rdev = new_encode_dev(stat->rdev);
#else
	tmp.st_dev = huge_encode_dev(stat->dev);
	tmp.st_rdev = huge_encode_dev(stat->rdev);
#endif
	tmp.st_ino = stat->ino;
	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
		return -EOVERFLOW;
#ifdef STAT64_HAS_BROKEN_ST_INO
	tmp.__st_ino = stat->ino;
#endif
	tmp.st_mode = stat->mode;
	tmp.st_nlink = stat->nlink;
	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
	tmp.st_atime = stat->atime.tv_sec;
	tmp.st_atime_nsec = stat->atime.tv_nsec;
	tmp.st_mtime = stat->mtime.tv_sec;
	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	tmp.st_ctime = stat->ctime.tv_sec;
	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
	tmp.st_size = stat->size;
	tmp.st_blocks = stat->blocks;
	tmp.st_blksize = stat->blksize;
	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
}

SYSCALL_DEFINE2(stat64, const char __user *, filename,
		struct stat64 __user *, statbuf)
{
	struct kstat stat;
	int error = vfs_stat(filename, &stat);

	if (!error)
		error = cp_new_stat64(&stat, statbuf);

	return error;
}

SYSCALL_DEFINE2(lstat64, const char __user *, filename,
		struct stat64 __user *, statbuf)
{
	struct kstat stat;
	int error = vfs_lstat(filename, &stat);

	if (!error)
		error = cp_new_stat64(&stat, statbuf);

	return error;
}

SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
{
	struct kstat stat;
	int error = vfs_fstat(fd, &stat);

	if (!error)
		error = cp_new_stat64(&stat, statbuf);

	return error;
}

SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
		struct stat64 __user *, statbuf, int, flag)
{
	struct kstat stat;
	int error;

	error = vfs_fstatat(dfd, filename, &stat, flag);
	if (error)
		return error;
	return cp_new_stat64(&stat, statbuf);
}
#endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */

/* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
void __inode_add_bytes(struct inode *inode, loff_t bytes)
{
	inode->i_blocks += bytes >> 9;
	bytes &= 511;
	inode->i_bytes += bytes;
	if (inode->i_bytes >= 512) {
		inode->i_blocks++;
		inode->i_bytes -= 512;
	}
}

void inode_add_bytes(struct inode *inode, loff_t bytes)
{
	spin_lock(&inode->i_lock);
	__inode_add_bytes(inode, bytes);
	spin_unlock(&inode->i_lock);
}

EXPORT_SYMBOL(inode_add_bytes);

void inode_sub_bytes(struct inode *inode, loff_t bytes)
{
	spin_lock(&inode->i_lock);
	inode->i_blocks -= bytes >> 9;
	bytes &= 511;
	if (inode->i_bytes < bytes) {
		inode->i_blocks--;
		inode->i_bytes += 512;
	}
	inode->i_bytes -= bytes;
	spin_unlock(&inode->i_lock);
}

EXPORT_SYMBOL(inode_sub_bytes);

loff_t inode_get_bytes(struct inode *inode)
{
	loff_t ret;

	spin_lock(&inode->i_lock);
	ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
	spin_unlock(&inode->i_lock);
	return ret;
}

EXPORT_SYMBOL(inode_get_bytes);

void inode_set_bytes(struct inode *inode, loff_t bytes)
{
	/* Caller is here responsible for sufficient locking
	 * (ie. inode->i_lock) */
	inode->i_blocks = bytes >> 9;
	inode->i_bytes = bytes & 511;
}

EXPORT_SYMBOL(inode_set_bytes);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/stat.c
	3	*
	4	* Copyright (C) 1991, 1992 Linus Torvalds
	5	*/
	6
630d9c47	7	#include <linux/export.h>
1da177e4 LT	8	#include <linux/mm.h>
	9	#include <linux/errno.h>
	10	#include <linux/file.h>
1da177e4 LT	11	#include <linux/highuid.h>
	12	#include <linux/fs.h>
	13	#include <linux/namei.h>
	14	#include <linux/security.h>
	15	#include <linux/syscalls.h>
ba52de12	16	#include <linux/pagemap.h>
1da177e4 LT	17
	18	#include <asm/uaccess.h>
	19	#include <asm/unistd.h>
	20
	21	void generic_fillattr(struct inode inode, struct kstat stat)
	22	{
	23	stat->dev = inode->i_sb->s_dev;
	24	stat->ino = inode->i_ino;
	25	stat->mode = inode->i_mode;
	26	stat->nlink = inode->i_nlink;
	27	stat->uid = inode->i_uid;
	28	stat->gid = inode->i_gid;
	29	stat->rdev = inode->i_rdev;
3ddcd056	30	stat->size = i_size_read(inode);
1da177e4 LT	31	stat->atime = inode->i_atime;
	32	stat->mtime = inode->i_mtime;
	33	stat->ctime = inode->i_ctime;
ba52de12	34	stat->blksize = (1 << inode->i_blkbits);
3ddcd056	35	stat->blocks = inode->i_blocks;
1da177e4 LT	36	}
	37
	38	EXPORT_SYMBOL(generic_fillattr);
	39
3dadecce	40	int vfs_getattr(struct path path, struct kstat stat)
1da177e4	41	{
3dadecce	42	struct inode *inode = path->dentry->d_inode;
1da177e4 LT	43	int retval;
1da177e4 LT	44
3dadecce	45	retval = security_inode_getattr(path->mnt, path->dentry);
1da177e4 LT	46	if (retval)
	47	return retval;
	48
	49	if (inode->i_op->getattr)
3dadecce	50	return inode->i_op->getattr(path->mnt, path->dentry, stat);
1da177e4 LT	51
1da177e4 LT	52	generic_fillattr(inode, stat);
1da177e4 LT	53	return 0;
	54	}
	55
	56	EXPORT_SYMBOL(vfs_getattr);
	57
1da177e4 LT	58	int vfs_fstat(unsigned int fd, struct kstat *stat)
1da177e4 LT	59	{
2903ff01	60	struct fd f = fdget_raw(fd);
1da177e4 LT	61	int error = -EBADF;
1da177e4 LT	62
2903ff01	63	if (f.file) {
3dadecce	64	error = vfs_getattr(&f.file->f_path, stat);
2903ff01	65	fdput(f);
1da177e4 LT	66	}
	67	return error;
	68	}
1da177e4 LT	69	EXPORT_SYMBOL(vfs_fstat);
1da177e4 LT	70
c7887325 DH	71	int vfs_fstatat(int dfd, const char __user filename, struct kstat stat,
c7887325 DH	72	int flag)
0112fc22	73	{
2eae7a18	74	struct path path;
0112fc22	75	int error = -EINVAL;
836fb7e7	76	unsigned int lookup_flags = 0;
0112fc22	77
65cfc672 AV	78	if ((flag & ~(AT_SYMLINK_NOFOLLOW \| AT_NO_AUTOMOUNT \|
65cfc672 AV	79	AT_EMPTY_PATH)) != 0)
0112fc22 OD	80	goto out;
0112fc22 OD	81
2eae7a18 CH	82	if (!(flag & AT_SYMLINK_NOFOLLOW))
2eae7a18 CH	83	lookup_flags \|= LOOKUP_FOLLOW;
65cfc672 AV	84	if (flag & AT_EMPTY_PATH)
65cfc672 AV	85	lookup_flags \|= LOOKUP_EMPTY;
836fb7e7	86	retry:
2eae7a18 CH	87	error = user_path_at(dfd, filename, lookup_flags, &path);
	88	if (error)
	89	goto out;
	90
3dadecce	91	error = vfs_getattr(&path, stat);
2eae7a18	92	path_put(&path);
836fb7e7 JL	93	if (retry_estale(error, lookup_flags)) {
	94	lookup_flags \|= LOOKUP_REVAL;
	95	goto retry;
	96	}
0112fc22 OD	97	out:
	98	return error;
	99	}
0112fc22 OD	100	EXPORT_SYMBOL(vfs_fstatat);
0112fc22 OD	101
c7887325	102	int vfs_stat(const char __user name, struct kstat stat)
2eae7a18 CH	103	{
	104	return vfs_fstatat(AT_FDCWD, name, stat, 0);
	105	}
	106	EXPORT_SYMBOL(vfs_stat);
	107
c7887325	108	int vfs_lstat(const char __user name, struct kstat stat)
2eae7a18 CH	109	{
	110	return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
	111	}
	112	EXPORT_SYMBOL(vfs_lstat);
	113
0112fc22	114
1da177e4 LT	115	#ifdef __ARCH_WANT_OLD_STAT
	116
	117	/*
	118	* For backward compatibility? Maybe this should be moved
	119	* into arch/i386 instead?
	120	*/
	121	static int cp_old_stat(struct kstat stat, struct __old_kernel_stat __user statbuf)
	122	{
	123	static int warncount = 5;
	124	struct __old_kernel_stat tmp;
	125
	126	if (warncount > 0) {
	127	warncount--;
	128	printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
	129	current->comm);
	130	} else if (warncount < 0) {
	131	/* it's laughable, but... */
	132	warncount = 0;
	133	}
	134
	135	memset(&tmp, 0, sizeof(struct __old_kernel_stat));
	136	tmp.st_dev = old_encode_dev(stat->dev);
	137	tmp.st_ino = stat->ino;
afefdbb2 DH	138	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
afefdbb2 DH	139	return -EOVERFLOW;
1da177e4 LT	140	tmp.st_mode = stat->mode;
	141	tmp.st_nlink = stat->nlink;
	142	if (tmp.st_nlink != stat->nlink)
	143	return -EOVERFLOW;
a7c1938e EB	144	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
a7c1938e EB	145	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
1da177e4 LT	146	tmp.st_rdev = old_encode_dev(stat->rdev);
	147	#if BITS_PER_LONG == 32
	148	if (stat->size > MAX_NON_LFS)
	149	return -EOVERFLOW;
	150	#endif
	151	tmp.st_size = stat->size;
	152	tmp.st_atime = stat->atime.tv_sec;
	153	tmp.st_mtime = stat->mtime.tv_sec;
	154	tmp.st_ctime = stat->ctime.tv_sec;
	155	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
	156	}
	157
c7887325 DH	158	SYSCALL_DEFINE2(stat, const char __user *, filename,
c7887325 DH	159	struct __old_kernel_stat __user *, statbuf)
1da177e4 LT	160	{
1da177e4 LT	161	struct kstat stat;
2eae7a18	162	int error;
1da177e4	163
2eae7a18 CH	164	error = vfs_stat(filename, &stat);
	165	if (error)
	166	return error;
1da177e4	167
2eae7a18	168	return cp_old_stat(&stat, statbuf);
1da177e4	169	}
257ac264	170
c7887325 DH	171	SYSCALL_DEFINE2(lstat, const char __user *, filename,
c7887325 DH	172	struct __old_kernel_stat __user *, statbuf)
1da177e4 LT	173	{
1da177e4 LT	174	struct kstat stat;
2eae7a18	175	int error;
1da177e4	176
2eae7a18 CH	177	error = vfs_lstat(filename, &stat);
	178	if (error)
	179	return error;
1da177e4	180
2eae7a18	181	return cp_old_stat(&stat, statbuf);
1da177e4	182	}
257ac264 HC	183
257ac264 HC	184	SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
1da177e4 LT	185	{
	186	struct kstat stat;
	187	int error = vfs_fstat(fd, &stat);
	188
	189	if (!error)
	190	error = cp_old_stat(&stat, statbuf);
	191
	192	return error;
	193	}
	194
	195	#endif /* __ARCH_WANT_OLD_STAT */
	196
a52dd971 LT	197	#if BITS_PER_LONG == 32
	198	# define choose_32_64(a,b) a
	199	#else
	200	# define choose_32_64(a,b) b
	201	#endif
	202
	203	#define valid_dev(x) choose_32_64(old_valid_dev,new_valid_dev)(x)
	204	#define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)
	205
8529f613 LT	206	#ifndef INIT_STRUCT_STAT_PADDING
	207	# define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
	208	#endif
	209
1da177e4 LT	210	static int cp_new_stat(struct kstat stat, struct stat __user statbuf)
	211	{
	212	struct stat tmp;
	213
a52dd971	214	if (!valid_dev(stat->dev) \|\| !valid_dev(stat->rdev))
1da177e4	215	return -EOVERFLOW;
a52dd971 LT	216	#if BITS_PER_LONG == 32
a52dd971 LT	217	if (stat->size > MAX_NON_LFS)
1da177e4 LT	218	return -EOVERFLOW;
	219	#endif
	220
8529f613	221	INIT_STRUCT_STAT_PADDING(tmp);
a52dd971	222	tmp.st_dev = encode_dev(stat->dev);
1da177e4	223	tmp.st_ino = stat->ino;
afefdbb2 DH	224	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
afefdbb2 DH	225	return -EOVERFLOW;
1da177e4 LT	226	tmp.st_mode = stat->mode;
	227	tmp.st_nlink = stat->nlink;
	228	if (tmp.st_nlink != stat->nlink)
	229	return -EOVERFLOW;
a7c1938e EB	230	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
a7c1938e EB	231	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
a52dd971	232	tmp.st_rdev = encode_dev(stat->rdev);
1da177e4 LT	233	tmp.st_size = stat->size;
	234	tmp.st_atime = stat->atime.tv_sec;
	235	tmp.st_mtime = stat->mtime.tv_sec;
	236	tmp.st_ctime = stat->ctime.tv_sec;
	237	#ifdef STAT_HAVE_NSEC
	238	tmp.st_atime_nsec = stat->atime.tv_nsec;
	239	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	240	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
	241	#endif
	242	tmp.st_blocks = stat->blocks;
	243	tmp.st_blksize = stat->blksize;
	244	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
	245	}
	246
c7887325 DH	247	SYSCALL_DEFINE2(newstat, const char __user *, filename,
c7887325 DH	248	struct stat __user *, statbuf)
5590ff0d UD	249	{
5590ff0d UD	250	struct kstat stat;
2eae7a18	251	int error = vfs_stat(filename, &stat);
5590ff0d	252
2eae7a18 CH	253	if (error)
	254	return error;
	255	return cp_new_stat(&stat, statbuf);
5590ff0d UD	256	}
5590ff0d UD	257
c7887325 DH	258	SYSCALL_DEFINE2(newlstat, const char __user *, filename,
c7887325 DH	259	struct stat __user *, statbuf)
1da177e4 LT	260	{
1da177e4 LT	261	struct kstat stat;
2eae7a18	262	int error;
1da177e4	263
2eae7a18 CH	264	error = vfs_lstat(filename, &stat);
	265	if (error)
	266	return error;
1da177e4	267
2eae7a18	268	return cp_new_stat(&stat, statbuf);
1da177e4	269	}
5590ff0d	270
2833c28a	271	#if !defined(__ARCH_WANT_STAT64) \|\| defined(__ARCH_WANT_SYS_NEWFSTATAT)
c7887325	272	SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
6559eed8	273	struct stat __user *, statbuf, int, flag)
1da177e4 LT	274	{
1da177e4 LT	275	struct kstat stat;
0112fc22	276	int error;
1da177e4	277
0112fc22 OD	278	error = vfs_fstatat(dfd, filename, &stat, flag);
	279	if (error)
	280	return error;
	281	return cp_new_stat(&stat, statbuf);
1da177e4	282	}
cff2b760	283	#endif
5590ff0d	284
257ac264	285	SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
1da177e4 LT	286	{
	287	struct kstat stat;
	288	int error = vfs_fstat(fd, &stat);
	289
	290	if (!error)
	291	error = cp_new_stat(&stat, statbuf);
	292
	293	return error;
	294	}
	295
6559eed8 HC	296	SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
6559eed8 HC	297	char __user *, buf, int, bufsiz)
1da177e4	298	{
2d8f3038	299	struct path path;
1da177e4	300	int error;
1fa1e7f6	301	int empty = 0;
7955119e	302	unsigned int lookup_flags = LOOKUP_EMPTY;
1da177e4 LT	303
	304	if (bufsiz <= 0)
	305	return -EINVAL;
	306
7955119e JL	307	retry:
7955119e JL	308	error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
1da177e4	309	if (!error) {
2d8f3038	310	struct inode *inode = path.dentry->d_inode;
1da177e4	311
1fa1e7f6	312	error = empty ? -ENOENT : -EINVAL;
acfa4380	313	if (inode->i_op->readlink) {
2d8f3038	314	error = security_inode_readlink(path.dentry);
1da177e4	315	if (!error) {
68ac1234	316	touch_atime(&path);
2d8f3038	317	error = inode->i_op->readlink(path.dentry,
4ac91378	318	buf, bufsiz);
1da177e4 LT	319	}
1da177e4 LT	320	}
2d8f3038	321	path_put(&path);
7955119e JL	322	if (retry_estale(error, lookup_flags)) {
	323	lookup_flags \|= LOOKUP_REVAL;
	324	goto retry;
	325	}
1da177e4 LT	326	}
	327	return error;
	328	}
	329
002c8976 HC	330	SYSCALL_DEFINE3(readlink, const char __user , path, char __user , buf,
002c8976 HC	331	int, bufsiz)
5590ff0d UD	332	{
	333	return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
	334	}
	335
1da177e4 LT	336
1da177e4 LT	337	/* ---------- LFS-64 ----------- */
0753f70f	338	#if defined(__ARCH_WANT_STAT64) \|\| defined(__ARCH_WANT_COMPAT_STAT64)
1da177e4	339
8529f613 LT	340	#ifndef INIT_STRUCT_STAT64_PADDING
	341	# define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
	342	#endif
	343
1da177e4 LT	344	static long cp_new_stat64(struct kstat stat, struct stat64 __user statbuf)
	345	{
	346	struct stat64 tmp;
	347
8529f613	348	INIT_STRUCT_STAT64_PADDING(tmp);
1da177e4 LT	349	#ifdef CONFIG_MIPS
	350	/* mips has weird padding, so we don't get 64 bits there */
	351	if (!new_valid_dev(stat->dev) \|\| !new_valid_dev(stat->rdev))
	352	return -EOVERFLOW;
	353	tmp.st_dev = new_encode_dev(stat->dev);
	354	tmp.st_rdev = new_encode_dev(stat->rdev);
	355	#else
	356	tmp.st_dev = huge_encode_dev(stat->dev);
	357	tmp.st_rdev = huge_encode_dev(stat->rdev);
	358	#endif
	359	tmp.st_ino = stat->ino;
afefdbb2 DH	360	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
afefdbb2 DH	361	return -EOVERFLOW;
1da177e4 LT	362	#ifdef STAT64_HAS_BROKEN_ST_INO
	363	tmp.__st_ino = stat->ino;
	364	#endif
	365	tmp.st_mode = stat->mode;
	366	tmp.st_nlink = stat->nlink;
a7c1938e EB	367	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
a7c1938e EB	368	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
1da177e4 LT	369	tmp.st_atime = stat->atime.tv_sec;
	370	tmp.st_atime_nsec = stat->atime.tv_nsec;
	371	tmp.st_mtime = stat->mtime.tv_sec;
	372	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	373	tmp.st_ctime = stat->ctime.tv_sec;
	374	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
	375	tmp.st_size = stat->size;
	376	tmp.st_blocks = stat->blocks;
	377	tmp.st_blksize = stat->blksize;
	378	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
	379	}
	380
c7887325 DH	381	SYSCALL_DEFINE2(stat64, const char __user *, filename,
c7887325 DH	382	struct stat64 __user *, statbuf)
1da177e4 LT	383	{
	384	struct kstat stat;
	385	int error = vfs_stat(filename, &stat);
	386
	387	if (!error)
	388	error = cp_new_stat64(&stat, statbuf);
	389
	390	return error;
	391	}
257ac264	392
c7887325 DH	393	SYSCALL_DEFINE2(lstat64, const char __user *, filename,
c7887325 DH	394	struct stat64 __user *, statbuf)
1da177e4 LT	395	{
	396	struct kstat stat;
	397	int error = vfs_lstat(filename, &stat);
	398
	399	if (!error)
	400	error = cp_new_stat64(&stat, statbuf);
	401
	402	return error;
	403	}
257ac264 HC	404
257ac264 HC	405	SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
1da177e4 LT	406	{
	407	struct kstat stat;
	408	int error = vfs_fstat(fd, &stat);
	409
	410	if (!error)
	411	error = cp_new_stat64(&stat, statbuf);
	412
	413	return error;
	414	}
	415
c7887325	416	SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
6559eed8	417	struct stat64 __user *, statbuf, int, flag)
cff2b760 UD	418	{
cff2b760 UD	419	struct kstat stat;
0112fc22	420	int error;
cff2b760	421
0112fc22 OD	422	error = vfs_fstatat(dfd, filename, &stat, flag);
	423	if (error)
	424	return error;
	425	return cp_new_stat64(&stat, statbuf);
cff2b760	426	}
0753f70f	427	#endif /* __ARCH_WANT_STAT64 \|\| __ARCH_WANT_COMPAT_STAT64 */
1da177e4	428
b462707e DM	429	/* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
b462707e DM	430	void __inode_add_bytes(struct inode *inode, loff_t bytes)
1da177e4	431	{
1da177e4 LT	432	inode->i_blocks += bytes >> 9;
	433	bytes &= 511;
	434	inode->i_bytes += bytes;
	435	if (inode->i_bytes >= 512) {
	436	inode->i_blocks++;
	437	inode->i_bytes -= 512;
	438	}
b462707e DM	439	}
	440
	441	void inode_add_bytes(struct inode *inode, loff_t bytes)
	442	{
	443	spin_lock(&inode->i_lock);
	444	__inode_add_bytes(inode, bytes);
1da177e4 LT	445	spin_unlock(&inode->i_lock);
	446	}
	447
	448	EXPORT_SYMBOL(inode_add_bytes);
	449
	450	void inode_sub_bytes(struct inode *inode, loff_t bytes)
	451	{
	452	spin_lock(&inode->i_lock);
	453	inode->i_blocks -= bytes >> 9;
	454	bytes &= 511;
	455	if (inode->i_bytes < bytes) {
	456	inode->i_blocks--;
	457	inode->i_bytes += 512;
	458	}
	459	inode->i_bytes -= bytes;
	460	spin_unlock(&inode->i_lock);
	461	}
	462
	463	EXPORT_SYMBOL(inode_sub_bytes);
	464
	465	loff_t inode_get_bytes(struct inode *inode)
	466	{
	467	loff_t ret;
	468
	469	spin_lock(&inode->i_lock);
	470	ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
	471	spin_unlock(&inode->i_lock);
	472	return ret;
	473	}
	474
	475	EXPORT_SYMBOL(inode_get_bytes);
	476
	477	void inode_set_bytes(struct inode *inode, loff_t bytes)
	478	{
	479	/* Caller is here responsible for sufficient locking
	480	* (ie. inode->i_lock) */
	481	inode->i_blocks = bytes >> 9;
	482	inode->i_bytes = bytes & 511;
	483	}
	484
	485	EXPORT_SYMBOL(inode_set_bytes);