[linux-block.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 vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
	struct inode *inode = dentry->d_inode;
	int retval;

	retval = security_inode_getattr(mnt, dentry);
	if (retval)
		return retval;

	if (inode->i_op->getattr)
		return inode->i_op->getattr(mnt, 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.mnt, f.file->f_path.dentry,
				    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.mnt, path.dentry, 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;

	if (bufsiz <= 0)
		return -EINVAL;

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