forked from luck/tmp_suning_uos_patched
8529f613b6
Admittedly this is something that the compiler should be able to just do for us, but gcc just isn't that smart. And trying to use a structure initializer (which would get us the right semantics) ends up resulting in gcc allocating stack space for _two_ 'struct stat', and then copying one into the other. So do it by hand - just have a per-architecture macro that initializes the padding fields. And if the architecture doesn't provide one, fall back to the old behavior of just doing the whole memset() first. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
476 lines
11 KiB
C
476 lines
11 KiB
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 file *f = fget(fd);
|
|
int error = -EBADF;
|
|
|
|
if (f) {
|
|
error = vfs_getattr(f->f_path.mnt, f->f_path.dentry, stat);
|
|
fput(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;
|
|
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;
|
|
|
|
error = user_path_at(dfd, filename, lookup_flags, &path);
|
|
if (error)
|
|
goto out;
|
|
|
|
error = vfs_getattr(path.mnt, path.dentry, stat);
|
|
path_put(&path);
|
|
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, 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;
|
|
}
|
|
|
|
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, stat->uid);
|
|
SET_GID(tmp.st_gid, 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 ----------- */
|
|
#ifdef __ARCH_WANT_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 = 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;
|
|
}
|
|
|
|
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 */
|
|
|
|
/* 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);
|