[GitHub/exynos8895/android_kernel_samsung_universal8895.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 = i_blocksize(inode);
	stat->blocks = inode->i_blocks;
}

EXPORT_SYMBOL(generic_fillattr);

/**
 * vfs_getattr_nosec - getattr without security checks
 * @path: file to get attributes from
 * @stat: structure to return attributes in
 *
 * Get attributes without calling security_inode_getattr.
 *
 * Currently the only caller other than vfs_getattr is internal to the
 * filehandle lookup code, which uses only the inode number and returns
 * no attributes to any user.  Any other code probably wants
 * vfs_getattr.
 */
int vfs_getattr_nosec(struct path *path, struct kstat *stat)
{
	struct inode *inode = d_backing_inode(path->dentry);

	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_nosec);

int vfs_getattr(struct path *path, struct kstat *stat)
{
	int retval;

	retval = security_inode_getattr(path);
	if (retval)
		return retval;
	return vfs_getattr_nosec(path, stat);
}

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 = d_backing_inode(path.dentry);

		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 */
	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;
	}
}
EXPORT_SYMBOL(__inode_add_bytes);

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)
{
	inode->i_blocks -= bytes >> 9;
	bytes &= 511;
	if (inode->i_bytes < bytes) {
		inode->i_blocks--;
		inode->i_bytes += 512;
	}
	inode->i_bytes -= bytes;
}

EXPORT_SYMBOL(__inode_sub_bytes);

void inode_sub_bytes(struct inode *inode, loff_t bytes)
{
	spin_lock(&inode->i_lock);
	__inode_sub_bytes(inode, 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;
04447026	34	stat->blksize = i_blocksize(inode);
3ddcd056	35	stat->blocks = inode->i_blocks;
1da177e4 LT	36	}
	37
	38	EXPORT_SYMBOL(generic_fillattr);
	39
b7a6ec52 BF	40	/**
	41	* vfs_getattr_nosec - getattr without security checks
	42	* @path: file to get attributes from
	43	* @stat: structure to return attributes in
	44	*
	45	* Get attributes without calling security_inode_getattr.
	46	*
	47	* Currently the only caller other than vfs_getattr is internal to the
	48	* filehandle lookup code, which uses only the inode number and returns
	49	* no attributes to any user. Any other code probably wants
	50	* vfs_getattr.
	51	*/
	52	int vfs_getattr_nosec(struct path path, struct kstat stat)
1da177e4	53	{
bb668734	54	struct inode *inode = d_backing_inode(path->dentry);
1da177e4 LT	55
1da177e4 LT	56	if (inode->i_op->getattr)
3dadecce	57	return inode->i_op->getattr(path->mnt, path->dentry, stat);
1da177e4 LT	58
1da177e4 LT	59	generic_fillattr(inode, stat);
1da177e4 LT	60	return 0;
	61	}
	62
b7a6ec52 BF	63	EXPORT_SYMBOL(vfs_getattr_nosec);
	64
	65	int vfs_getattr(struct path path, struct kstat stat)
	66	{
	67	int retval;
	68
3f7036a0	69	retval = security_inode_getattr(path);
b7a6ec52 BF	70	if (retval)
	71	return retval;
	72	return vfs_getattr_nosec(path, stat);
	73	}
	74
1da177e4 LT	75	EXPORT_SYMBOL(vfs_getattr);
1da177e4 LT	76
1da177e4 LT	77	int vfs_fstat(unsigned int fd, struct kstat *stat)
1da177e4 LT	78	{
2903ff01	79	struct fd f = fdget_raw(fd);
1da177e4 LT	80	int error = -EBADF;
1da177e4 LT	81
2903ff01	82	if (f.file) {
3dadecce	83	error = vfs_getattr(&f.file->f_path, stat);
2903ff01	84	fdput(f);
1da177e4 LT	85	}
	86	return error;
	87	}
1da177e4 LT	88	EXPORT_SYMBOL(vfs_fstat);
1da177e4 LT	89
c7887325 DH	90	int vfs_fstatat(int dfd, const char __user filename, struct kstat stat,
c7887325 DH	91	int flag)
0112fc22	92	{
2eae7a18	93	struct path path;
0112fc22	94	int error = -EINVAL;
836fb7e7	95	unsigned int lookup_flags = 0;
0112fc22	96
65cfc672 AV	97	if ((flag & ~(AT_SYMLINK_NOFOLLOW \| AT_NO_AUTOMOUNT \|
65cfc672 AV	98	AT_EMPTY_PATH)) != 0)
0112fc22 OD	99	goto out;
0112fc22 OD	100
2eae7a18 CH	101	if (!(flag & AT_SYMLINK_NOFOLLOW))
2eae7a18 CH	102	lookup_flags \|= LOOKUP_FOLLOW;
65cfc672 AV	103	if (flag & AT_EMPTY_PATH)
65cfc672 AV	104	lookup_flags \|= LOOKUP_EMPTY;
836fb7e7	105	retry:
2eae7a18 CH	106	error = user_path_at(dfd, filename, lookup_flags, &path);
	107	if (error)
	108	goto out;
	109
3dadecce	110	error = vfs_getattr(&path, stat);
2eae7a18	111	path_put(&path);
836fb7e7 JL	112	if (retry_estale(error, lookup_flags)) {
	113	lookup_flags \|= LOOKUP_REVAL;
	114	goto retry;
	115	}
0112fc22 OD	116	out:
	117	return error;
	118	}
0112fc22 OD	119	EXPORT_SYMBOL(vfs_fstatat);
0112fc22 OD	120
c7887325	121	int vfs_stat(const char __user name, struct kstat stat)
2eae7a18 CH	122	{
	123	return vfs_fstatat(AT_FDCWD, name, stat, 0);
	124	}
	125	EXPORT_SYMBOL(vfs_stat);
	126
c7887325	127	int vfs_lstat(const char __user name, struct kstat stat)
2eae7a18 CH	128	{
	129	return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
	130	}
	131	EXPORT_SYMBOL(vfs_lstat);
	132
0112fc22	133
1da177e4 LT	134	#ifdef __ARCH_WANT_OLD_STAT
	135
	136	/*
	137	* For backward compatibility? Maybe this should be moved
	138	* into arch/i386 instead?
	139	*/
	140	static int cp_old_stat(struct kstat stat, struct __old_kernel_stat __user statbuf)
	141	{
	142	static int warncount = 5;
	143	struct __old_kernel_stat tmp;
	144
	145	if (warncount > 0) {
	146	warncount--;
	147	printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
	148	current->comm);
	149	} else if (warncount < 0) {
	150	/* it's laughable, but... */
	151	warncount = 0;
	152	}
	153
	154	memset(&tmp, 0, sizeof(struct __old_kernel_stat));
	155	tmp.st_dev = old_encode_dev(stat->dev);
	156	tmp.st_ino = stat->ino;
afefdbb2 DH	157	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
afefdbb2 DH	158	return -EOVERFLOW;
1da177e4 LT	159	tmp.st_mode = stat->mode;
	160	tmp.st_nlink = stat->nlink;
	161	if (tmp.st_nlink != stat->nlink)
	162	return -EOVERFLOW;
a7c1938e EB	163	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
a7c1938e EB	164	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
1da177e4 LT	165	tmp.st_rdev = old_encode_dev(stat->rdev);
	166	#if BITS_PER_LONG == 32
	167	if (stat->size > MAX_NON_LFS)
	168	return -EOVERFLOW;
	169	#endif
	170	tmp.st_size = stat->size;
	171	tmp.st_atime = stat->atime.tv_sec;
	172	tmp.st_mtime = stat->mtime.tv_sec;
	173	tmp.st_ctime = stat->ctime.tv_sec;
	174	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
	175	}
	176
c7887325 DH	177	SYSCALL_DEFINE2(stat, const char __user *, filename,
c7887325 DH	178	struct __old_kernel_stat __user *, statbuf)
1da177e4 LT	179	{
1da177e4 LT	180	struct kstat stat;
2eae7a18	181	int error;
1da177e4	182
2eae7a18 CH	183	error = vfs_stat(filename, &stat);
	184	if (error)
	185	return error;
1da177e4	186
2eae7a18	187	return cp_old_stat(&stat, statbuf);
1da177e4	188	}
257ac264	189
c7887325 DH	190	SYSCALL_DEFINE2(lstat, const char __user *, filename,
c7887325 DH	191	struct __old_kernel_stat __user *, statbuf)
1da177e4 LT	192	{
1da177e4 LT	193	struct kstat stat;
2eae7a18	194	int error;
1da177e4	195
2eae7a18 CH	196	error = vfs_lstat(filename, &stat);
	197	if (error)
	198	return error;
1da177e4	199
2eae7a18	200	return cp_old_stat(&stat, statbuf);
1da177e4	201	}
257ac264 HC	202
257ac264 HC	203	SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
1da177e4 LT	204	{
	205	struct kstat stat;
	206	int error = vfs_fstat(fd, &stat);
	207
	208	if (!error)
	209	error = cp_old_stat(&stat, statbuf);
	210
	211	return error;
	212	}
	213
	214	#endif /* __ARCH_WANT_OLD_STAT */
	215
a52dd971 LT	216	#if BITS_PER_LONG == 32
	217	# define choose_32_64(a,b) a
	218	#else
	219	# define choose_32_64(a,b) b
	220	#endif
	221
	222	#define valid_dev(x) choose_32_64(old_valid_dev,new_valid_dev)(x)
	223	#define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x)
	224
8529f613 LT	225	#ifndef INIT_STRUCT_STAT_PADDING
	226	# define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
	227	#endif
	228
1da177e4 LT	229	static int cp_new_stat(struct kstat stat, struct stat __user statbuf)
	230	{
	231	struct stat tmp;
	232
a52dd971	233	if (!valid_dev(stat->dev) \|\| !valid_dev(stat->rdev))
1da177e4	234	return -EOVERFLOW;
a52dd971 LT	235	#if BITS_PER_LONG == 32
a52dd971 LT	236	if (stat->size > MAX_NON_LFS)
1da177e4 LT	237	return -EOVERFLOW;
	238	#endif
	239
8529f613	240	INIT_STRUCT_STAT_PADDING(tmp);
a52dd971	241	tmp.st_dev = encode_dev(stat->dev);
1da177e4	242	tmp.st_ino = stat->ino;
afefdbb2 DH	243	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
afefdbb2 DH	244	return -EOVERFLOW;
1da177e4 LT	245	tmp.st_mode = stat->mode;
	246	tmp.st_nlink = stat->nlink;
	247	if (tmp.st_nlink != stat->nlink)
	248	return -EOVERFLOW;
a7c1938e EB	249	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
a7c1938e EB	250	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
a52dd971	251	tmp.st_rdev = encode_dev(stat->rdev);
1da177e4 LT	252	tmp.st_size = stat->size;
	253	tmp.st_atime = stat->atime.tv_sec;
	254	tmp.st_mtime = stat->mtime.tv_sec;
	255	tmp.st_ctime = stat->ctime.tv_sec;
	256	#ifdef STAT_HAVE_NSEC
	257	tmp.st_atime_nsec = stat->atime.tv_nsec;
	258	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	259	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
	260	#endif
	261	tmp.st_blocks = stat->blocks;
	262	tmp.st_blksize = stat->blksize;
	263	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
	264	}
	265
c7887325 DH	266	SYSCALL_DEFINE2(newstat, const char __user *, filename,
c7887325 DH	267	struct stat __user *, statbuf)
5590ff0d UD	268	{
5590ff0d UD	269	struct kstat stat;
2eae7a18	270	int error = vfs_stat(filename, &stat);
5590ff0d	271
2eae7a18 CH	272	if (error)
	273	return error;
	274	return cp_new_stat(&stat, statbuf);
5590ff0d UD	275	}
5590ff0d UD	276
c7887325 DH	277	SYSCALL_DEFINE2(newlstat, const char __user *, filename,
c7887325 DH	278	struct stat __user *, statbuf)
1da177e4 LT	279	{
1da177e4 LT	280	struct kstat stat;
2eae7a18	281	int error;
1da177e4	282
2eae7a18 CH	283	error = vfs_lstat(filename, &stat);
	284	if (error)
	285	return error;
1da177e4	286
2eae7a18	287	return cp_new_stat(&stat, statbuf);
1da177e4	288	}
5590ff0d	289
2833c28a	290	#if !defined(__ARCH_WANT_STAT64) \|\| defined(__ARCH_WANT_SYS_NEWFSTATAT)
c7887325	291	SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
6559eed8	292	struct stat __user *, statbuf, int, flag)
1da177e4 LT	293	{
1da177e4 LT	294	struct kstat stat;
0112fc22	295	int error;
1da177e4	296
0112fc22 OD	297	error = vfs_fstatat(dfd, filename, &stat, flag);
	298	if (error)
	299	return error;
	300	return cp_new_stat(&stat, statbuf);
1da177e4	301	}
cff2b760	302	#endif
5590ff0d	303
257ac264	304	SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
1da177e4 LT	305	{
	306	struct kstat stat;
	307	int error = vfs_fstat(fd, &stat);
	308
	309	if (!error)
	310	error = cp_new_stat(&stat, statbuf);
	311
	312	return error;
	313	}
	314
6559eed8 HC	315	SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
6559eed8 HC	316	char __user *, buf, int, bufsiz)
1da177e4	317	{
2d8f3038	318	struct path path;
1da177e4	319	int error;
1fa1e7f6	320	int empty = 0;
7955119e	321	unsigned int lookup_flags = LOOKUP_EMPTY;
1da177e4 LT	322
	323	if (bufsiz <= 0)
	324	return -EINVAL;
	325
7955119e JL	326	retry:
7955119e JL	327	error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
1da177e4	328	if (!error) {
bb668734	329	struct inode *inode = d_backing_inode(path.dentry);
1da177e4	330
1fa1e7f6	331	error = empty ? -ENOENT : -EINVAL;
acfa4380	332	if (inode->i_op->readlink) {
2d8f3038	333	error = security_inode_readlink(path.dentry);
1da177e4	334	if (!error) {
68ac1234	335	touch_atime(&path);
2d8f3038	336	error = inode->i_op->readlink(path.dentry,
4ac91378	337	buf, bufsiz);
1da177e4 LT	338	}
1da177e4 LT	339	}
2d8f3038	340	path_put(&path);
7955119e JL	341	if (retry_estale(error, lookup_flags)) {
	342	lookup_flags \|= LOOKUP_REVAL;
	343	goto retry;
	344	}
1da177e4 LT	345	}
	346	return error;
	347	}
	348
002c8976 HC	349	SYSCALL_DEFINE3(readlink, const char __user , path, char __user , buf,
002c8976 HC	350	int, bufsiz)
5590ff0d UD	351	{
	352	return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
	353	}
	354
1da177e4 LT	355
1da177e4 LT	356	/* ---------- LFS-64 ----------- */
0753f70f	357	#if defined(__ARCH_WANT_STAT64) \|\| defined(__ARCH_WANT_COMPAT_STAT64)
1da177e4	358
8529f613 LT	359	#ifndef INIT_STRUCT_STAT64_PADDING
	360	# define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
	361	#endif
	362
1da177e4 LT	363	static long cp_new_stat64(struct kstat stat, struct stat64 __user statbuf)
	364	{
	365	struct stat64 tmp;
	366
8529f613	367	INIT_STRUCT_STAT64_PADDING(tmp);
1da177e4 LT	368	#ifdef CONFIG_MIPS
1da177e4 LT	369	/* mips has weird padding, so we don't get 64 bits there */
1da177e4 LT	370	tmp.st_dev = new_encode_dev(stat->dev);
	371	tmp.st_rdev = new_encode_dev(stat->rdev);
	372	#else
	373	tmp.st_dev = huge_encode_dev(stat->dev);
	374	tmp.st_rdev = huge_encode_dev(stat->rdev);
	375	#endif
	376	tmp.st_ino = stat->ino;
afefdbb2 DH	377	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
afefdbb2 DH	378	return -EOVERFLOW;
1da177e4 LT	379	#ifdef STAT64_HAS_BROKEN_ST_INO
	380	tmp.__st_ino = stat->ino;
	381	#endif
	382	tmp.st_mode = stat->mode;
	383	tmp.st_nlink = stat->nlink;
a7c1938e EB	384	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
a7c1938e EB	385	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
1da177e4 LT	386	tmp.st_atime = stat->atime.tv_sec;
	387	tmp.st_atime_nsec = stat->atime.tv_nsec;
	388	tmp.st_mtime = stat->mtime.tv_sec;
	389	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	390	tmp.st_ctime = stat->ctime.tv_sec;
	391	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
	392	tmp.st_size = stat->size;
	393	tmp.st_blocks = stat->blocks;
	394	tmp.st_blksize = stat->blksize;
	395	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
	396	}
	397
c7887325 DH	398	SYSCALL_DEFINE2(stat64, const char __user *, filename,
c7887325 DH	399	struct stat64 __user *, statbuf)
1da177e4 LT	400	{
	401	struct kstat stat;
	402	int error = vfs_stat(filename, &stat);
	403
	404	if (!error)
	405	error = cp_new_stat64(&stat, statbuf);
	406
	407	return error;
	408	}
257ac264	409
c7887325 DH	410	SYSCALL_DEFINE2(lstat64, const char __user *, filename,
c7887325 DH	411	struct stat64 __user *, statbuf)
1da177e4 LT	412	{
	413	struct kstat stat;
	414	int error = vfs_lstat(filename, &stat);
	415
	416	if (!error)
	417	error = cp_new_stat64(&stat, statbuf);
	418
	419	return error;
	420	}
257ac264 HC	421
257ac264 HC	422	SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
1da177e4 LT	423	{
	424	struct kstat stat;
	425	int error = vfs_fstat(fd, &stat);
	426
	427	if (!error)
	428	error = cp_new_stat64(&stat, statbuf);
	429
	430	return error;
	431	}
	432
c7887325	433	SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
6559eed8	434	struct stat64 __user *, statbuf, int, flag)
cff2b760 UD	435	{
cff2b760 UD	436	struct kstat stat;
0112fc22	437	int error;
cff2b760	438
0112fc22 OD	439	error = vfs_fstatat(dfd, filename, &stat, flag);
	440	if (error)
	441	return error;
	442	return cp_new_stat64(&stat, statbuf);
cff2b760	443	}
0753f70f	444	#endif /* __ARCH_WANT_STAT64 \|\| __ARCH_WANT_COMPAT_STAT64 */
1da177e4	445
b462707e DM	446	/* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
b462707e DM	447	void __inode_add_bytes(struct inode *inode, loff_t bytes)
1da177e4	448	{
1da177e4 LT	449	inode->i_blocks += bytes >> 9;
	450	bytes &= 511;
	451	inode->i_bytes += bytes;
	452	if (inode->i_bytes >= 512) {
	453	inode->i_blocks++;
	454	inode->i_bytes -= 512;
	455	}
b462707e	456	}
4c516dff	457	EXPORT_SYMBOL(__inode_add_bytes);
b462707e DM	458
	459	void inode_add_bytes(struct inode *inode, loff_t bytes)
	460	{
	461	spin_lock(&inode->i_lock);
	462	__inode_add_bytes(inode, bytes);
1da177e4 LT	463	spin_unlock(&inode->i_lock);
	464	}
	465
	466	EXPORT_SYMBOL(inode_add_bytes);
	467
1c8924eb	468	void __inode_sub_bytes(struct inode *inode, loff_t bytes)
1da177e4	469	{
1da177e4 LT	470	inode->i_blocks -= bytes >> 9;
	471	bytes &= 511;
	472	if (inode->i_bytes < bytes) {
	473	inode->i_blocks--;
	474	inode->i_bytes += 512;
	475	}
	476	inode->i_bytes -= bytes;
1c8924eb JK	477	}
	478
	479	EXPORT_SYMBOL(__inode_sub_bytes);
	480
	481	void inode_sub_bytes(struct inode *inode, loff_t bytes)
	482	{
	483	spin_lock(&inode->i_lock);
	484	__inode_sub_bytes(inode, bytes);
1da177e4 LT	485	spin_unlock(&inode->i_lock);
	486	}
	487
	488	EXPORT_SYMBOL(inode_sub_bytes);
	489
	490	loff_t inode_get_bytes(struct inode *inode)
	491	{
	492	loff_t ret;
	493
	494	spin_lock(&inode->i_lock);
	495	ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
	496	spin_unlock(&inode->i_lock);
	497	return ret;
	498	}
	499
	500	EXPORT_SYMBOL(inode_get_bytes);
	501
	502	void inode_set_bytes(struct inode *inode, loff_t bytes)
	503	{
	504	/* Caller is here responsible for sufficient locking
	505	* (ie. inode->i_lock) */
	506	inode->i_blocks = bytes >> 9;
	507	inode->i_bytes = bytes & 511;
	508	}
	509
	510	EXPORT_SYMBOL(inode_set_bytes);