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/*
* linux/fs/ext3/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/jbd.h>
#include <linux/capability.h>
#include <linux/ext3_fs.h>
#include <linux/ext3_jbd.h>
#include <linux/time.h>
#include <asm/uaccess.h>
int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
unsigned long arg)
{
struct ext3_inode_info *ei = EXT3_I(inode);
unsigned int flags;
unsigned short rsv_window_size;
ext3_debug ("cmd = %u, arg = %lu\n", cmd, arg);
switch (cmd) {
case EXT3_IOC_GETFLAGS:
flags = ei->i_flags & EXT3_FL_USER_VISIBLE;
return put_user(flags, (int __user *) arg);
case EXT3_IOC_SETFLAGS: {
handle_t *handle = NULL;
int err;
struct ext3_iloc iloc;
unsigned int oldflags;
unsigned int jflag;
if (IS_RDONLY(inode))
return -EROFS;
if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
return -EACCES;
if (get_user(flags, (int __user *) arg))
return -EFAULT;
if (!S_ISDIR(inode->i_mode))
flags &= ~EXT3_DIRSYNC_FL;
oldflags = ei->i_flags;
/* The JOURNAL_DATA flag is modifiable only by root */
jflag = flags & EXT3_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) & (EXT3_APPEND_FL | EXT3_IMMUTABLE_FL)) {
if (!capable(CAP_LINUX_IMMUTABLE))
return -EPERM;
}
/*
* The JOURNAL_DATA flag can only be changed by
* the relevant capability.
*/
if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) {
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
}
handle = ext3_journal_start(inode, 1);
if (IS_ERR(handle))
return PTR_ERR(handle);
if (IS_SYNC(inode))
handle->h_sync = 1;
err = ext3_reserve_inode_write(handle, inode, &iloc);
if (err)
goto flags_err;
flags = flags & EXT3_FL_USER_MODIFIABLE;
flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
ei->i_flags = flags;
ext3_set_inode_flags(inode);
inode->i_ctime = CURRENT_TIME_SEC;
err = ext3_mark_iloc_dirty(handle, inode, &iloc);
flags_err:
ext3_journal_stop(handle);
if (err)
return err;
if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
err = ext3_change_inode_journal_flag(inode, jflag);
return err;
}
case EXT3_IOC_GETVERSION:
case EXT3_IOC_GETVERSION_OLD:
return put_user(inode->i_generation, (int __user *) arg);
case EXT3_IOC_SETVERSION:
case EXT3_IOC_SETVERSION_OLD: {
handle_t *handle;
struct ext3_iloc iloc;
__u32 generation;
int err;
if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
return -EPERM;
if (IS_RDONLY(inode))
return -EROFS;
if (get_user(generation, (int __user *) arg))
return -EFAULT;
handle = ext3_journal_start(inode, 1);
if (IS_ERR(handle))
return PTR_ERR(handle);
err = ext3_reserve_inode_write(handle, inode, &iloc);
if (err == 0) {
inode->i_ctime = CURRENT_TIME_SEC;
inode->i_generation = generation;
err = ext3_mark_iloc_dirty(handle, inode, &iloc);
}
ext3_journal_stop(handle);
return err;
}
#ifdef CONFIG_JBD_DEBUG
case EXT3_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(&EXT3_SB(sb)->ro_wait_queue, &wait);
if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) {
schedule();
ret = 1;
}
remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
return ret;
}
#endif
case EXT3_IOC_GETRSVSZ:
if (test_opt(inode->i_sb, RESERVATION)
&& S_ISREG(inode->i_mode)
&& ei->i_block_alloc_info) {
rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
return put_user(rsv_window_size, (int __user *)arg);
}
return -ENOTTY;
case EXT3_IOC_SETRSVSZ: {
if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
return -ENOTTY;
if (IS_RDONLY(inode))
return -EROFS;
if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
return -EACCES;
if (get_user(rsv_window_size, (int __user *)arg))
return -EFAULT;
if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
/*
* need to allocate reservation structure for this inode
* before set the window size
*/
mutex_lock(&ei->truncate_mutex);
if (!ei->i_block_alloc_info)
ext3_init_block_alloc_info(inode);
if (ei->i_block_alloc_info){
struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
rsv->rsv_goal_size = rsv_window_size;
}
mutex_unlock(&ei->truncate_mutex);
return 0;
}
case EXT3_IOC_GROUP_EXTEND: {
unsigned long n_blocks_count;
struct super_block *sb = inode->i_sb;
int err;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
if (IS_RDONLY(inode))
return -EROFS;
if (get_user(n_blocks_count, (__u32 __user *)arg))
return -EFAULT;
err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
journal_lock_updates(EXT3_SB(sb)->s_journal);
journal_flush(EXT3_SB(sb)->s_journal);
journal_unlock_updates(EXT3_SB(sb)->s_journal);
return err;
}
case EXT3_IOC_GROUP_ADD: {
struct ext3_new_group_data input;
struct super_block *sb = inode->i_sb;
int err;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
if (IS_RDONLY(inode))
return -EROFS;
if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
sizeof(input)))
return -EFAULT;
err = ext3_group_add(sb, &input);
journal_lock_updates(EXT3_SB(sb)->s_journal);
journal_flush(EXT3_SB(sb)->s_journal);
journal_unlock_updates(EXT3_SB(sb)->s_journal);
return err;
}
default:
return -ENOTTY;
}
}
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