linux/arch/parisc/hpux/fs.c
David Howells afefdbb28a [PATCH] VFS: Make filldir_t and struct kstat deal in 64-bit inode numbers
These patches make the kernel pass 64-bit inode numbers internally when
communicating to userspace, even on a 32-bit system.  They are required
because some filesystems have intrinsic 64-bit inode numbers: NFS3+ and XFS
for example.  The 64-bit inode numbers are then propagated to userspace
automatically where the arch supports it.

Problems have been seen with userspace (eg: ld.so) using the 64-bit inode
number returned by stat64() or getdents64() to differentiate files, and
failing because the 64-bit inode number space was compressed to 32-bits, and
so overlaps occur.

This patch:

Make filldir_t take a 64-bit inode number and struct kstat carry a 64-bit
inode number so that 64-bit inode numbers can be passed back to userspace.

The stat functions then returns the full 64-bit inode number where
available and where possible.  If it is not possible to represent the inode
number supplied by the filesystem in the field provided by userspace, then
error EOVERFLOW will be issued.

Similarly, the getdents/readdir functions now pass the full 64-bit inode
number to userspace where possible, returning EOVERFLOW instead when a
directory entry is encountered that can't be properly represented.

Note that this means that some inodes will not be stat'able on a 32-bit
system with old libraries where they were before - but it does mean that
there will be no ambiguity over what a 32-bit inode number refers to.

Note similarly that directory scans may be cut short with an error on a
32-bit system with old libraries where the scan would work before for the
same reasons.

It is judged unlikely that this situation will occur because modern glibc
uses 64-bit capable versions of stat and getdents class functions
exclusively, and that older systems are unlikely to encounter
unrepresentable inode numbers anyway.

[akpm: alpha build fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:03:40 -07:00

204 lines
4.9 KiB
C

/*
* Implements HPUX syscalls.
*
* Copyright (C) 1999 Matthew Wilcox <willy with parisc-linux.org>
* Copyright (C) 2000 Michael Ang <mang with subcarrier.org>
* Copyright (C) 2000 John Marvin <jsm with parisc-linux.org>
* Copyright (C) 2000 Philipp Rumpf
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/file.h>
#include <linux/smp_lock.h>
#include <linux/slab.h>
#include <linux/ptrace.h>
#include <asm/errno.h>
#include <asm/uaccess.h>
int hpux_execve(struct pt_regs *regs)
{
int error;
char *filename;
filename = getname((char *) regs->gr[26]);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename, (char **) regs->gr[25],
(char **)regs->gr[24], regs);
if (error == 0) {
task_lock(current);
current->ptrace &= ~PT_DTRACE;
task_unlock(current);
}
putname(filename);
out:
return error;
}
struct hpux_dirent {
loff_t d_off;
ino_t d_ino;
short d_reclen;
short d_namlen;
char d_name[1];
};
struct getdents_callback {
struct hpux_dirent *current_dir;
struct hpux_dirent *previous;
int count;
int error;
};
#define NAME_OFFSET(de) ((int) ((de)->d_name - (char *) (de)))
#define ROUND_UP(x) (((x)+sizeof(long)-1) & ~(sizeof(long)-1))
static int filldir(void * __buf, const char * name, int namlen, loff_t offset,
ino_t ino, unsigned d_type)
{
struct hpux_dirent * dirent;
struct getdents_callback * buf = (struct getdents_callback *) __buf;
ino_t d_ino;
int reclen = ROUND_UP(NAME_OFFSET(dirent) + namlen + 1);
buf->error = -EINVAL; /* only used if we fail.. */
if (reclen > buf->count)
return -EINVAL;
d_ino = ino;
if (sizeof(d_ino) < sizeof(ino) && d_ino != ino)
return -EOVERFLOW;
dirent = buf->previous;
if (dirent)
put_user(offset, &dirent->d_off);
dirent = buf->current_dir;
buf->previous = dirent;
put_user(d_ino, &dirent->d_ino);
put_user(reclen, &dirent->d_reclen);
put_user(namlen, &dirent->d_namlen);
copy_to_user(dirent->d_name, name, namlen);
put_user(0, dirent->d_name + namlen);
((char *) dirent) += reclen;
buf->current_dir = dirent;
buf->count -= reclen;
return 0;
}
#undef NAME_OFFSET
#undef ROUND_UP
int hpux_getdents(unsigned int fd, struct hpux_dirent *dirent, unsigned int count)
{
struct file * file;
struct hpux_dirent * lastdirent;
struct getdents_callback buf;
int error = -EBADF;
file = fget(fd);
if (!file)
goto out;
buf.current_dir = dirent;
buf.previous = NULL;
buf.count = count;
buf.error = 0;
error = vfs_readdir(file, filldir, &buf);
if (error < 0)
goto out_putf;
error = buf.error;
lastdirent = buf.previous;
if (lastdirent) {
put_user(file->f_pos, &lastdirent->d_off);
error = count - buf.count;
}
out_putf:
fput(file);
out:
return error;
}
int hpux_mount(const char *fs, const char *path, int mflag,
const char *fstype, const char *dataptr, int datalen)
{
return -ENOSYS;
}
static int cp_hpux_stat(struct kstat *stat, struct hpux_stat64 *statbuf)
{
struct hpux_stat64 tmp;
/* we probably want a different split here - is hpux 12:20? */
if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
return -EOVERFLOW;
memset(&tmp, 0, sizeof(tmp));
tmp.st_dev = new_encode_dev(stat->dev);
tmp.st_ino = stat->ino;
tmp.st_mode = stat->mode;
tmp.st_nlink = stat->nlink;
tmp.st_uid = stat->uid;
tmp.st_gid = stat->gid;
tmp.st_rdev = new_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;
tmp.st_blocks = stat->blocks;
tmp.st_blksize = stat->blksize;
return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
}
long hpux_stat64(char *filename, struct hpux_stat64 *statbuf)
{
struct kstat stat;
int error = vfs_stat(filename, &stat);
if (!error)
error = cp_hpux_stat(&stat, statbuf);
return error;
}
long hpux_fstat64(unsigned int fd, struct hpux_stat64 *statbuf)
{
struct kstat stat;
int error = vfs_fstat(fd, &stat);
if (!error)
error = cp_hpux_stat(&stat, statbuf);
return error;
}
long hpux_lstat64(char *filename, struct hpux_stat64 *statbuf)
{
struct kstat stat;
int error = vfs_lstat(filename, &stat);
if (!error)
error = cp_hpux_stat(&stat, statbuf);
return error;
}