- 根目录:
- fs
- ext4
- ioctl.c
/*
* linux/fs/ext4/ioctl.c
*
* Copyright (C) 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*/
#include <linux/fs.h>
#include <linux/jbd2.h>
#include <linux/capability.h>
#include <linux/time.h>
#include <linux/compat.h>
#include <linux/mount.h>
#include <linux/file.h>
#include <asm/uaccess.h>
#include "ext4_jbd2.h"
#include "ext4.h"
long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct inode *inode = filp->f_dentry->d_inode;
struct ext4_inode_info *ei = EXT4_I(inode);
unsigned int flags;
ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
switch (cmd) {
case EXT4_IOC_GETFLAGS:
ext4_get_inode_flags(ei);
flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
return put_user(flags, (int __user *) arg);
case EXT4_IOC_SETFLAGS: {
handle_t *handle = NULL;
int err, migrate = 0;
struct ext4_iloc iloc;
unsigned int oldflags;
unsigned int jflag;
if (!inode_owner_or_capable(inode))
return -EACCES;
if (get_user(flags, (int __user *) arg))
return -EFAULT;
err = mnt_want_write(filp->f_path.mnt);
if (err)
return err;
flags = ext4_mask_flags(inode->i_mode, flags);
err = -EPERM;
mutex_lock(&inode->i_mutex);
/* Is it quota file? Do not allow user to mess with it */
if (IS_NOQUOTA(inode))
goto flags_out;
oldflags = ei->i_flags;
/* The JOURNAL_DATA flag is modifiable only by root */
jflag = flags & EXT4_JOURNAL_DATA_FL;
/*
* The IMMUTABLE and APPEND_ONLY flags can only be changed by
* the relevant capability.
*
* This test looks nicer. Thanks to Pauline Middelink
*/
if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
if (!capable(CAP_LINUX_IMMUTABLE))
goto flags_out;
}
/*
* The JOURNAL_DATA flag can only be changed by
* the relevant capability.
*/
if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
if (!capable(CAP_SYS_RESOURCE))
goto flags_out;
}
if (oldflags & EXT4_EXTENTS_FL) {
/* We don't support clearning extent flags */
if (!(flags & EXT4_EXTENTS_FL)) {
err = -EOPNOTSUPP;
goto flags_out;
}
} else if (flags & EXT4_EXTENTS_FL) {
/* migrate the file */
migrate = 1;
flags &= ~EXT4_EXTENTS_FL;
}
if (flags & EXT4_EOFBLOCKS_FL) {
/* we don't support adding EOFBLOCKS flag */
if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
err = -EOPNOTSUPP;
goto flags_out;
}
} else if (oldflags & EXT4_EOFBLOCKS_FL)
ext4_truncate(inode);
handle = ext4_journal_start(inode, 1);
if (IS_ERR(handle)) {
err = PTR_ERR(handle);
goto flags_out;
}
if (IS_SYNC(inode))
ext4_handle_sync(handle);
err = ext4_reserve_inode_write(handle, inode, &iloc);
if (err)
goto flags_err;
flags = flags & EXT4_FL_USER_MODIFIABLE;
flags |= oldflags & ~EXT4_FL_USER_MODIFIABLE;
ei->i_flags = flags;
ext4_set_inode_flags(inode);
inode->i_ctime = ext4_current_time(inode);
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
flags_err:
ext4_journal_stop(handle);
if (err)
goto flags_out;
if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
err = ext4_change_inode_journal_flag(inode, jflag);
if (err)
goto flags_out;
if (migrate)
err = ext4_ext_migrate(inode);
flags_out:
mutex_unlock(&inode->i_mutex);
mnt_drop_write(filp->f_path.mnt);
return err;
}
case EXT4_IOC_GETVERSION:
case EXT4_IOC_GETVERSION_OLD:
return put_user(inode->i_generation, (int __user *) arg);
case EXT4_IOC_SETVERSION:
case EXT4_IOC_SETVERSION_OLD: {
handle_t *handle;
struct ext4_iloc iloc;
__u32 generation;
int err;
if (!inode_owner_or_capable(inode))
return -EPERM;
err = mnt_want_write(filp->f_path.mnt);
if (err)
return err;
if (get_user(generation, (int __user *) arg)) {
err = -EFAULT;
goto setversion_out;
}
handle = ext4_journal_start(inode, 1);
if (IS_ERR(handle)) {
err = PTR_ERR(handle);
goto setversion_out;
}
err = ext4_reserve_inode_write(handle, inode, &iloc);
if (err == 0) {
inode->i_ctime = ext4_current_time(inode);
inode->i_generation = generation;
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
}
ext4_journal_stop(handle);
setversion_out:
mnt_drop_write(filp->f_path.mnt);
return err;
}
#ifdef CONFIG_JBD2_DEBUG
case EXT4_IOC_WAIT_FOR_READONLY:
/*
* This is racy - by the time we're woken up and running,
* the superblock could be released. And the module could
* have been unloaded. So sue me.
*
* Returns 1 if it slept, else zero.
*/
{
struct super_block *sb = inode->i_sb;
DECLARE_WAITQUEUE(wait, current);
int ret = 0;
set_current_state(TASK_INTERRUPTIBLE);
add_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait);
if (timer_pending(&EXT4_SB(sb)->turn_ro_timer)) {
schedule();
ret = 1;
}
remove_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait);
return ret;
}
#endif
case EXT4_IOC_GROUP_EXTEND: {
ext4_fsblk_t n_blocks_count;
struct super_block *sb = inode->i_sb;
int err, err2=0;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
if (get_user(n_blocks_count, (__u32 __user *)arg))
return -EFAULT;
err = mnt_want_write(filp->f_path.mnt);
if (err)
return err;
err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
if (EXT4_SB(sb)->s_journal) {
jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
}
if (err == 0)
err = err2;
mnt_drop_write(filp->f_path.mnt);
return err;
}
case EXT4_IOC_MOVE_EXT: {
struct move_extent me;
struct file *donor_filp;
int err;
if (!(filp->f_mode & FMODE_READ) ||
!(filp->f_mode & FMODE_WRITE))
return -EBADF;
if (copy_from_user(&me,
(struct move_extent __user *)arg, sizeof(me)))
return -EFAULT;
me.moved_len = 0;
donor_filp = fget(me.donor_fd);
if (!donor_filp)
return -EBADF;
if (!(donor_filp->f_mode & FMODE_WRITE)) {
err = -EBADF;
goto mext_out;
}
err = mnt_want_write(filp->f_path.mnt);
if (err)
goto mext_out;
err = ext4_move_extents(filp, donor_filp, me.orig_start,
me.donor_start, me.len, &me.moved_len);
mnt_drop_write(filp->f_path.mnt);
if (me.moved_len > 0)
file_remove_suid(donor_filp);
if (copy_to_user((struct move_extent __user *)arg,
&me, sizeof(me)))
err = -EFAULT;
mext_out:
fput(donor_filp);
return err;
}
case EXT4_IOC_GROUP_ADD: {
struct ext4_new_group_data input;
struct super_block *sb = inode->i_sb;
int err, err2=0;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
sizeof(input)))
return -EFAULT;
err = mnt_want_write(filp->f_path.mnt);
if (err)
return err;
err = ext4_group_add(sb, &input);
if (EXT4_SB(sb)->s_journal) {
jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
}
if (err == 0)
err = err2;
mnt_drop_write(filp->f_path.mnt);
return err;
}
case EXT4_IOC_MIGRATE:
{
int err;
if (!inode_owner_or_capable(inode))
return -EACCES;
err = mnt_want_write(filp->f_path.mnt);
if (err)
return err;
/*
* inode_mutex prevent write and truncate on the file.
* Read still goes through. We take i_data_sem in
* ext4_ext_swap_inode_data before we switch the
* inode format to prevent read.
*/
mutex_lock(&(inode->i_mutex));
err = ext4_ext_migrate(inode);
mutex_unlock(&(inode->i_mutex));
mnt_drop_write(filp->f_path.mnt);
return err;
}
case EXT4_IOC_ALLOC_DA_BLKS:
{
int err;
if (!inode_owner_or_capable(inode))
return -EACCES;
err = mnt_want_write(filp->f_path.mnt);
if (err)
return err;
err = ext4_alloc_da_blocks(inode);
mnt_drop_write(filp->f_path.mnt);
return err;
}
case FITRIM:
{
struct super_block *sb = inode->i_sb;
struct request_queue *q = bdev_get_queue(sb->s_bdev);
struct fstrim_range range;
int ret = 0;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (!blk_queue_discard(q))
return -EOPNOTSUPP;
if (copy_from_user(&range, (struct fstrim_range *)arg,
sizeof(range)))
return -EFAULT;
range.minlen = max((unsigned int)range.minlen,
q->limits.discard_granularity);
ret = ext4_trim_fs(sb, &range);
if (ret < 0)
return ret;
if (copy_to_user((struct fstrim_range *)arg, &range,
sizeof(range)))
return -EFAULT;
return 0;
}
default:
return -ENOTTY;
}
}
#ifdef CONFIG_COMPAT
long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
/* These are just misnamed, they actually get/put from/to user an int */
switch (cmd) {
case EXT4_IOC32_GETFLAGS:
cmd = EXT4_IOC_GETFLAGS;
break;
case EXT4_IOC32_SETFLAGS:
cmd = EXT4_IOC_SETFLAGS;
break;
case EXT4_IOC32_GETVERSION:
cmd = EXT4_IOC_GETVERSION;
break;
case EXT4_IOC32_SETVERSION:
cmd = EXT4_IOC_SETVERSION;
break;
case EXT4_IOC32_GROUP_EXTEND:
cmd = EXT4_IOC_GROUP_EXTEND;
break;
case EXT4_IOC32_GETVERSION_OLD:
cmd = EXT4_IOC_GETVERSION_OLD;
break;
case EXT4_IOC32_SETVERSION_OLD:
cmd = EXT4_IOC_SETVERSION_OLD;
break;
#ifdef CONFIG_JBD2_DEBUG
case EXT4_IOC32_WAIT_FOR_READONLY:
cmd = EXT4_IOC_WAIT_FOR_READONLY;
break;
#endif
case EXT4_IOC32_GETRSVSZ:
cmd = EXT4_IOC_GETRSVSZ;
break;
case EXT4_IOC32_SETRSVSZ:
cmd = EXT4_IOC_SETRSVSZ;
break;
case EXT4_IOC32_GROUP_ADD: {
struct compat_ext4_new_group_input __user *uinput;
struct ext4_new_group_input input;
mm_segment_t old_fs;
int err;
uinput = compat_ptr(arg);
err = get_user(input.group, &uinput->group);
err |= get_user(input.block_bitmap, &uinput->block_bitmap);
err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
err |= get_user(input.inode_table, &uinput->inode_table);
err |= get_user(input.blocks_count, &uinput->blocks_count);
err |= get_user(input.reserved_blocks,
&uinput->reserved_blocks);
if (err)
return -EFAULT;
old_fs = get_fs();
set_fs(KERNEL_DS);
err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
(unsigned long) &input);
set_fs(old_fs);
return err;
}
case EXT4_IOC_MOVE_EXT:
case FITRIM:
break;
default:
return -ENOIOCTLCMD;
}
return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
}
#endif