[linux.git] / fs / stat.c

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

#include <linux/config.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/smp_lock.h>
#include <linux/highuid.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/security.h>
#include <linux/syscalls.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->atime = inode->i_atime;
	stat->mtime = inode->i_mtime;
	stat->ctime = inode->i_ctime;
	stat->size = i_size_read(inode);
	stat->blocks = inode->i_blocks;
	stat->blksize = inode->i_blksize;
}

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);
	if (!stat->blksize) {
		struct super_block *s = inode->i_sb;
		unsigned blocks;
		blocks = (stat->size+s->s_blocksize-1) >> s->s_blocksize_bits;
		stat->blocks = (s->s_blocksize / 512) * blocks;
		stat->blksize = s->s_blocksize;
	}
	return 0;
}

EXPORT_SYMBOL(vfs_getattr);

int vfs_stat_fd(int dfd, char __user *name, struct kstat *stat)
{
	struct nameidata nd;
	int error;

	error = __user_walk_fd(dfd, name, LOOKUP_FOLLOW, &nd);
	if (!error) {
		error = vfs_getattr(nd.mnt, nd.dentry, stat);
		path_release(&nd);
	}
	return error;
}

int vfs_stat(char __user *name, struct kstat *stat)
{
	return vfs_stat_fd(AT_FDCWD, name, stat);
}

EXPORT_SYMBOL(vfs_stat);

int vfs_lstat_fd(int dfd, char __user *name, struct kstat *stat)
{
	struct nameidata nd;
	int error;

	error = __user_walk_fd(dfd, name, 0, &nd);
	if (!error) {
		error = vfs_getattr(nd.mnt, nd.dentry, stat);
		path_release(&nd);
	}
	return error;
}

int vfs_lstat(char __user *name, struct kstat *stat)
{
	return vfs_lstat_fd(AT_FDCWD, name, stat);
}

EXPORT_SYMBOL(vfs_lstat);

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

	if (f) {
		error = vfs_getattr(f->f_vfsmnt, f->f_dentry, stat);
		fput(f);
	}
	return error;
}

EXPORT_SYMBOL(vfs_fstat);

#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;
	tmp.st_mode = stat->mode;
	tmp.st_nlink = stat->nlink;
	if (tmp.st_nlink != stat->nlink)
		return -EOVERFLOW;
	SET_UID(tmp.st_uid, stat->uid);
	SET_GID(tmp.st_gid, 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;
}

asmlinkage long sys_stat(char __user * filename, struct __old_kernel_stat __user * statbuf)
{
	struct kstat stat;
	int error = vfs_stat_fd(AT_FDCWD, filename, &stat);

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

	return error;
}
asmlinkage long sys_lstat(char __user * filename, struct __old_kernel_stat __user * statbuf)
{
	struct kstat stat;
	int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);

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

	return error;
}
asmlinkage long sys_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 */

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

#if BITS_PER_LONG == 32
	if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
		return -EOVERFLOW;
#else
	if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
		return -EOVERFLOW;
#endif

	memset(&tmp, 0, sizeof(tmp));
#if BITS_PER_LONG == 32
	tmp.st_dev = old_encode_dev(stat->dev);
#else
	tmp.st_dev = new_encode_dev(stat->dev);
#endif
	tmp.st_ino = stat->ino;
	tmp.st_mode = stat->mode;
	tmp.st_nlink = stat->nlink;
	if (tmp.st_nlink != stat->nlink)
		return -EOVERFLOW;
	SET_UID(tmp.st_uid, stat->uid);
	SET_GID(tmp.st_gid, stat->gid);
#if BITS_PER_LONG == 32
	tmp.st_rdev = old_encode_dev(stat->rdev);
#else
	tmp.st_rdev = new_encode_dev(stat->rdev);
#endif
#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;
#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;
}

asmlinkage long sys_newstat(char __user *filename, struct stat __user *statbuf)
{
	struct kstat stat;
	int error = vfs_stat_fd(AT_FDCWD, filename, &stat);

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

	return error;
}

asmlinkage long sys_newlstat(char __user *filename, struct stat __user *statbuf)
{
	struct kstat stat;
	int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);

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

	return error;
}

asmlinkage long sys_newfstatat(int dfd, char __user *filename,
				struct stat __user *statbuf, int flag)
{
	struct kstat stat;
	int error = -EINVAL;

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

	if (flag & AT_SYMLINK_NOFOLLOW)
		error = vfs_lstat_fd(dfd, filename, &stat);
	else
		error = vfs_stat_fd(dfd, filename, &stat);

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

out:
	return error;
}

asmlinkage long sys_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;
}

asmlinkage long sys_readlinkat(int dfd, const char __user *path,
				char __user *buf, int bufsiz)
{
	struct nameidata nd;
	int error;

	if (bufsiz <= 0)
		return -EINVAL;

	error = __user_walk_fd(dfd, path, 0, &nd);
	if (!error) {
		struct inode * inode = nd.dentry->d_inode;

		error = -EINVAL;
		if (inode->i_op && inode->i_op->readlink) {
			error = security_inode_readlink(nd.dentry);
			if (!error) {
				touch_atime(nd.mnt, nd.dentry);
				error = inode->i_op->readlink(nd.dentry, buf, bufsiz);
			}
		}
		path_release(&nd);
	}
	return error;
}

asmlinkage long sys_readlink(const char __user *path, char __user *buf,
				int bufsiz)
{
	return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
}


/* ---------- LFS-64 ----------- */
#ifdef __ARCH_WANT_STAT64

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

	memset(&tmp, 0, sizeof(struct stat64));
#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;
#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 = stat->uid;
	tmp.st_gid = 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;
}

asmlinkage long sys_stat64(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;
}
asmlinkage long sys_lstat64(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;
}
asmlinkage long sys_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;
}

#endif /* __ARCH_WANT_STAT64 */

void inode_add_bytes(struct inode *inode, loff_t bytes)
{
	spin_lock(&inode->i_lock);
	inode->i_blocks += bytes >> 9;
	bytes &= 511;
	inode->i_bytes += bytes;
	if (inode->i_bytes >= 512) {
		inode->i_blocks++;
		inode->i_bytes -= 512;
	}
	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
	7	#include <linux/config.h>
	8	#include <linux/module.h>
	9	#include <linux/mm.h>
	10	#include <linux/errno.h>
	11	#include <linux/file.h>
	12	#include <linux/smp_lock.h>
	13	#include <linux/highuid.h>
	14	#include <linux/fs.h>
	15	#include <linux/namei.h>
	16	#include <linux/security.h>
	17	#include <linux/syscalls.h>
	18
	19	#include <asm/uaccess.h>
	20	#include <asm/unistd.h>
	21
	22	void generic_fillattr(struct inode inode, struct kstat stat)
	23	{
	24	stat->dev = inode->i_sb->s_dev;
	25	stat->ino = inode->i_ino;
	26	stat->mode = inode->i_mode;
	27	stat->nlink = inode->i_nlink;
	28	stat->uid = inode->i_uid;
	29	stat->gid = inode->i_gid;
	30	stat->rdev = inode->i_rdev;
	31	stat->atime = inode->i_atime;
	32	stat->mtime = inode->i_mtime;
	33	stat->ctime = inode->i_ctime;
	34	stat->size = i_size_read(inode);
	35	stat->blocks = inode->i_blocks;
	36	stat->blksize = inode->i_blksize;
	37	}
	38
	39	EXPORT_SYMBOL(generic_fillattr);
	40
	41	int vfs_getattr(struct vfsmount mnt, struct dentry dentry, struct kstat *stat)
	42	{
	43	struct inode *inode = dentry->d_inode;
	44	int retval;
	45
	46	retval = security_inode_getattr(mnt, dentry);
	47	if (retval)
	48	return retval;
	49
	50	if (inode->i_op->getattr)
	51	return inode->i_op->getattr(mnt, dentry, stat);
	52
	53	generic_fillattr(inode, stat);
	54	if (!stat->blksize) {
	55	struct super_block *s = inode->i_sb;
	56	unsigned blocks;
	57	blocks = (stat->size+s->s_blocksize-1) >> s->s_blocksize_bits;
	58	stat->blocks = (s->s_blocksize / 512) * blocks;
	59	stat->blksize = s->s_blocksize;
	60	}
	61	return 0;
	62	}
	63
	64	EXPORT_SYMBOL(vfs_getattr);
65
5590ff0d	66	int vfs_stat_fd(int dfd, char __user name, struct kstat stat)
1da177e4 LT	67	{
	68	struct nameidata nd;
	69	int error;
	70
5590ff0d	71	error = __user_walk_fd(dfd, name, LOOKUP_FOLLOW, &nd);
1da177e4 LT	72	if (!error) {
	73	error = vfs_getattr(nd.mnt, nd.dentry, stat);
	74	path_release(&nd);
	75	}
	76	return error;
	77	}
	78
5590ff0d UD	79	int vfs_stat(char __user name, struct kstat stat)
	80	{
	81	return vfs_stat_fd(AT_FDCWD, name, stat);
	82	}
	83
1da177e4 LT	84	EXPORT_SYMBOL(vfs_stat);
1da177e4 LT	85
5590ff0d	86	int vfs_lstat_fd(int dfd, char __user name, struct kstat stat)
1da177e4 LT	87	{
	88	struct nameidata nd;
	89	int error;
	90
5590ff0d	91	error = __user_walk_fd(dfd, name, 0, &nd);
1da177e4 LT	92	if (!error) {
	93	error = vfs_getattr(nd.mnt, nd.dentry, stat);
	94	path_release(&nd);
	95	}
	96	return error;
	97	}
	98
5590ff0d UD	99	int vfs_lstat(char __user name, struct kstat stat)
	100	{
	101	return vfs_lstat_fd(AT_FDCWD, name, stat);
	102	}
	103
1da177e4 LT	104	EXPORT_SYMBOL(vfs_lstat);
	105
	106	int vfs_fstat(unsigned int fd, struct kstat *stat)
	107	{
	108	struct file *f = fget(fd);
	109	int error = -EBADF;
	110
	111	if (f) {
	112	error = vfs_getattr(f->f_vfsmnt, f->f_dentry, stat);
	113	fput(f);
	114	}
	115	return error;
	116	}
	117
	118	EXPORT_SYMBOL(vfs_fstat);
	119
	120	#ifdef __ARCH_WANT_OLD_STAT
	121
	122	/*
	123	* For backward compatibility? Maybe this should be moved
	124	* into arch/i386 instead?
	125	*/
	126	static int cp_old_stat(struct kstat stat, struct __old_kernel_stat __user statbuf)
	127	{
	128	static int warncount = 5;
	129	struct __old_kernel_stat tmp;
	130
	131	if (warncount > 0) {
	132	warncount--;
	133	printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
	134	current->comm);
	135	} else if (warncount < 0) {
	136	/* it's laughable, but... */
	137	warncount = 0;
	138	}
	139
	140	memset(&tmp, 0, sizeof(struct __old_kernel_stat));
	141	tmp.st_dev = old_encode_dev(stat->dev);
	142	tmp.st_ino = stat->ino;
	143	tmp.st_mode = stat->mode;
	144	tmp.st_nlink = stat->nlink;
	145	if (tmp.st_nlink != stat->nlink)
	146	return -EOVERFLOW;
	147	SET_UID(tmp.st_uid, stat->uid);
	148	SET_GID(tmp.st_gid, stat->gid);
	149	tmp.st_rdev = old_encode_dev(stat->rdev);
	150	#if BITS_PER_LONG == 32
	151	if (stat->size > MAX_NON_LFS)
	152	return -EOVERFLOW;
	153	#endif
	154	tmp.st_size = stat->size;
	155	tmp.st_atime = stat->atime.tv_sec;
	156	tmp.st_mtime = stat->mtime.tv_sec;
	157	tmp.st_ctime = stat->ctime.tv_sec;
	158	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
	159	}
	160
	161	asmlinkage long sys_stat(char __user * filename, struct __old_kernel_stat __user * statbuf)
	162	{
	163	struct kstat stat;
5590ff0d	164	int error = vfs_stat_fd(AT_FDCWD, filename, &stat);
1da177e4 LT	165
	166	if (!error)
	167	error = cp_old_stat(&stat, statbuf);
	168
	169	return error;
	170	}
	171	asmlinkage long sys_lstat(char __user * filename, struct __old_kernel_stat __user * statbuf)
	172	{
	173	struct kstat stat;
5590ff0d	174	int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);
1da177e4 LT	175
	176	if (!error)
	177	error = cp_old_stat(&stat, statbuf);
	178
	179	return error;
	180	}
	181	asmlinkage long sys_fstat(unsigned int fd, struct __old_kernel_stat __user * statbuf)
	182	{
	183	struct kstat stat;
	184	int error = vfs_fstat(fd, &stat);
	185
	186	if (!error)
	187	error = cp_old_stat(&stat, statbuf);
	188
	189	return error;
	190	}
	191
	192	#endif /* __ARCH_WANT_OLD_STAT */
	193
	194	static int cp_new_stat(struct kstat stat, struct stat __user statbuf)
	195	{
	196	struct stat tmp;
	197
	198	#if BITS_PER_LONG == 32
	199	if (!old_valid_dev(stat->dev) \|\| !old_valid_dev(stat->rdev))
	200	return -EOVERFLOW;
	201	#else
	202	if (!new_valid_dev(stat->dev) \|\| !new_valid_dev(stat->rdev))
	203	return -EOVERFLOW;
	204	#endif
	205
	206	memset(&tmp, 0, sizeof(tmp));
	207	#if BITS_PER_LONG == 32
	208	tmp.st_dev = old_encode_dev(stat->dev);
	209	#else
	210	tmp.st_dev = new_encode_dev(stat->dev);
	211	#endif
	212	tmp.st_ino = stat->ino;
	213	tmp.st_mode = stat->mode;
	214	tmp.st_nlink = stat->nlink;
	215	if (tmp.st_nlink != stat->nlink)
	216	return -EOVERFLOW;
	217	SET_UID(tmp.st_uid, stat->uid);
	218	SET_GID(tmp.st_gid, stat->gid);
	219	#if BITS_PER_LONG == 32
	220	tmp.st_rdev = old_encode_dev(stat->rdev);
	221	#else
	222	tmp.st_rdev = new_encode_dev(stat->rdev);
	223	#endif
	224	#if BITS_PER_LONG == 32
	225	if (stat->size > MAX_NON_LFS)
	226	return -EOVERFLOW;
	227	#endif
	228	tmp.st_size = stat->size;
	229	tmp.st_atime = stat->atime.tv_sec;
	230	tmp.st_mtime = stat->mtime.tv_sec;
	231	tmp.st_ctime = stat->ctime.tv_sec;
	232	#ifdef STAT_HAVE_NSEC
	233	tmp.st_atime_nsec = stat->atime.tv_nsec;
	234	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	235	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
	236	#endif
	237	tmp.st_blocks = stat->blocks;
	238	tmp.st_blksize = stat->blksize;
239	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
240	}
241
5590ff0d UD	242	asmlinkage long sys_newstat(char __user filename, struct stat __user statbuf)
	243	{
	244	struct kstat stat;
	245	int error = vfs_stat_fd(AT_FDCWD, filename, &stat);
	246
	247	if (!error)
	248	error = cp_new_stat(&stat, statbuf);
	249
	250	return error;
	251	}
	252
	253	asmlinkage long sys_newlstat(char __user filename, struct stat __user statbuf)
1da177e4 LT	254	{
1da177e4 LT	255	struct kstat stat;
5590ff0d	256	int error = vfs_lstat_fd(AT_FDCWD, filename, &stat);
1da177e4 LT	257
	258	if (!error)
	259	error = cp_new_stat(&stat, statbuf);
	260
	261	return error;
	262	}
5590ff0d UD	263
	264	asmlinkage long sys_newfstatat(int dfd, char __user *filename,
	265	struct stat __user *statbuf, int flag)
1da177e4 LT	266	{
1da177e4 LT	267	struct kstat stat;
5590ff0d UD	268	int error = -EINVAL;
	269
	270	if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
	271	goto out;
	272
	273	if (flag & AT_SYMLINK_NOFOLLOW)
	274	error = vfs_lstat_fd(dfd, filename, &stat);
	275	else
	276	error = vfs_stat_fd(dfd, filename, &stat);
1da177e4 LT	277
	278	if (!error)
	279	error = cp_new_stat(&stat, statbuf);
	280
5590ff0d	281	out:
1da177e4 LT	282	return error;
1da177e4 LT	283	}
5590ff0d UD	284
5590ff0d UD	285	asmlinkage long sys_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
5590ff0d UD	296	asmlinkage long sys_readlinkat(int dfd, const char __user *path,
5590ff0d UD	297	char __user *buf, int bufsiz)
1da177e4 LT	298	{
	299	struct nameidata nd;
	300	int error;
	301
	302	if (bufsiz <= 0)
	303	return -EINVAL;
	304
5590ff0d	305	error = __user_walk_fd(dfd, path, 0, &nd);
1da177e4 LT	306	if (!error) {
	307	struct inode * inode = nd.dentry->d_inode;
	308
	309	error = -EINVAL;
	310	if (inode->i_op && inode->i_op->readlink) {
	311	error = security_inode_readlink(nd.dentry);
	312	if (!error) {
	313	touch_atime(nd.mnt, nd.dentry);
	314	error = inode->i_op->readlink(nd.dentry, buf, bufsiz);
	315	}
	316	}
	317	path_release(&nd);
	318	}
	319	return error;
	320	}
	321
5590ff0d UD	322	asmlinkage long sys_readlink(const char __user path, char __user buf,
	323	int bufsiz)
	324	{
	325	return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
	326	}
	327
1da177e4 LT	328
	329	/* ---------- LFS-64 ----------- */
	330	#ifdef __ARCH_WANT_STAT64
	331
	332	static long cp_new_stat64(struct kstat stat, struct stat64 __user statbuf)
	333	{
	334	struct stat64 tmp;
	335
	336	memset(&tmp, 0, sizeof(struct stat64));
	337	#ifdef CONFIG_MIPS
	338	/* mips has weird padding, so we don't get 64 bits there */
	339	if (!new_valid_dev(stat->dev) \|\| !new_valid_dev(stat->rdev))
	340	return -EOVERFLOW;
	341	tmp.st_dev = new_encode_dev(stat->dev);
	342	tmp.st_rdev = new_encode_dev(stat->rdev);
	343	#else
	344	tmp.st_dev = huge_encode_dev(stat->dev);
	345	tmp.st_rdev = huge_encode_dev(stat->rdev);
	346	#endif
	347	tmp.st_ino = stat->ino;
	348	#ifdef STAT64_HAS_BROKEN_ST_INO
	349	tmp.__st_ino = stat->ino;
	350	#endif
	351	tmp.st_mode = stat->mode;
	352	tmp.st_nlink = stat->nlink;
	353	tmp.st_uid = stat->uid;
	354	tmp.st_gid = stat->gid;
	355	tmp.st_atime = stat->atime.tv_sec;
	356	tmp.st_atime_nsec = stat->atime.tv_nsec;
	357	tmp.st_mtime = stat->mtime.tv_sec;
	358	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
	359	tmp.st_ctime = stat->ctime.tv_sec;
	360	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
	361	tmp.st_size = stat->size;
	362	tmp.st_blocks = stat->blocks;
	363	tmp.st_blksize = stat->blksize;
	364	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
	365	}
	366
	367	asmlinkage long sys_stat64(char __user * filename, struct stat64 __user * statbuf)
	368	{
	369	struct kstat stat;
	370	int error = vfs_stat(filename, &stat);
	371
	372	if (!error)
	373	error = cp_new_stat64(&stat, statbuf);
	374
	375	return error;
	376	}
	377	asmlinkage long sys_lstat64(char __user * filename, struct stat64 __user * statbuf)
	378	{
	379	struct kstat stat;
	380	int error = vfs_lstat(filename, &stat);
	381
	382	if (!error)
	383	error = cp_new_stat64(&stat, statbuf);
	384
	385	return error;
	386	}
	387	asmlinkage long sys_fstat64(unsigned long fd, struct stat64 __user * statbuf)
	388	{
	389	struct kstat stat;
	390	int error = vfs_fstat(fd, &stat);
	391
392	if (!error)
393	error = cp_new_stat64(&stat, statbuf);
394
395	return error;
396	}
397
398	#endif /* __ARCH_WANT_STAT64 */
399
400	void inode_add_bytes(struct inode *inode, loff_t bytes)
401	{
402	spin_lock(&inode->i_lock);
403	inode->i_blocks += bytes >> 9;
404	bytes &= 511;
405	inode->i_bytes += bytes;
406	if (inode->i_bytes >= 512) {
407	inode->i_blocks++;
408	inode->i_bytes -= 512;
409	}
410	spin_unlock(&inode->i_lock);
411	}
412
413	EXPORT_SYMBOL(inode_add_bytes);
414
415	void inode_sub_bytes(struct inode *inode, loff_t bytes)
416	{
417	spin_lock(&inode->i_lock);
418	inode->i_blocks -= bytes >> 9;
419	bytes &= 511;
420	if (inode->i_bytes < bytes) {
421	inode->i_blocks--;
422	inode->i_bytes += 512;
423	}
424	inode->i_bytes -= bytes;
425	spin_unlock(&inode->i_lock);
426	}
427
428	EXPORT_SYMBOL(inode_sub_bytes);
429
430	loff_t inode_get_bytes(struct inode *inode)
431	{
432	loff_t ret;
433
434	spin_lock(&inode->i_lock);
435	ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
436	spin_unlock(&inode->i_lock);
437	return ret;
438	}
439
440	EXPORT_SYMBOL(inode_get_bytes);
441
442	void inode_set_bytes(struct inode *inode, loff_t bytes)
443	{
444	/* Caller is here responsible for sufficient locking
445	* (ie. inode->i_lock) */
446	inode->i_blocks = bytes >> 9;
447	inode->i_bytes = bytes & 511;
448	}
449
450	EXPORT_SYMBOL(inode_set_bytes);