mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 10:19:47 +00:00
![Ulrich Drepper](/assets/img/avatar_default.png)
The *at patches introduced fstatat and, due to inusfficient research, I used the newfstat functions generally as the guideline. The result is that on 32-bit platforms we don't have all the information needed to implement fstatat64. This patch modifies the code to pass up 64-bit information if __ARCH_WANT_STAT64 is defined. I renamed the syscall entry point to make this clear. Other archs will continue to use the existing code. On x86-64 the compat code is implemented using a new sys32_ function. this is what is done for the other stat syscalls as well. This patch might break some other archs (those which define __ARCH_WANT_STAT64 and which already wired up the syscall). Yet others might need changes to accomodate the compatibility mode. I really don't want to do that work because all this stat handling is a mess (more so in glibc, but the kernel is also affected). It should be done by the arch maintainers. I'll provide some stand-alone test shortly. Those who are eager could compile glibc and run 'make check' (no installation needed). The patch below has been tested on x86 and x86-64. Signed-off-by: Ulrich Drepper <drepper@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
472 lines
10 KiB
C
472 lines
10 KiB
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;
|
|
}
|
|
|
|
#ifndef __ARCH_WANT_STAT64
|
|
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;
|
|
}
|
|
#endif
|
|
|
|
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;
|
|
}
|
|
|
|
asmlinkage long sys_fstatat64(int dfd, char __user *filename,
|
|
struct stat64 __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_stat64(&stat, statbuf);
|
|
|
|
out:
|
|
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);
|