/* * 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/smp_lock.h> #include <linux/mount.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; unsigned short rsv_window_size; 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; struct ext4_iloc iloc; unsigned int oldflags; unsigned int jflag; if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(flags, (int __user *) arg)) return -EFAULT; err = mnt_want_write(filp->f_path.mnt); if (err) return err; if (!S_ISDIR(inode->i_mode)) flags &= ~EXT4_DIRSYNC_FL; 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; } handle = ext4_journal_start(inode, 1); if (IS_ERR(handle)) { err = PTR_ERR(handle); goto flags_out; } if (IS_SYNC(inode)) handle->h_sync = 1; 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); 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 (!is_owner_or_cap(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_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 EXT4_IOC_SETRSVSZ: { int err; if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode)) return -ENOTTY; if (!is_owner_or_cap(inode)) return -EACCES; if (get_user(rsv_window_size, (int __user *)arg)) return -EFAULT; err = mnt_want_write(filp->f_path.mnt); if (err) return err; if (rsv_window_size > EXT4_MAX_RESERVE_BLOCKS) rsv_window_size = EXT4_MAX_RESERVE_BLOCKS; /* * need to allocate reservation structure for this inode * before set the window size */ down_write(&ei->i_data_sem); if (!ei->i_block_alloc_info) ext4_init_block_alloc_info(inode); if (ei->i_block_alloc_info){ struct ext4_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node; rsv->rsv_goal_size = rsv_window_size; } up_write(&ei->i_data_sem); mnt_drop_write(filp->f_path.mnt); return 0; } case EXT4_IOC_GROUP_EXTEND: { ext4_fsblk_t n_blocks_count; struct super_block *sb = inode->i_sb; int err; 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); jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal); jbd2_journal_flush(EXT4_SB(sb)->s_journal); jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal); mnt_drop_write(filp->f_path.mnt); return err; } case EXT4_IOC_GROUP_ADD: { struct ext4_new_group_data input; struct super_block *sb = inode->i_sb; int err; 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); jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal); jbd2_journal_flush(EXT4_SB(sb)->s_journal); jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal); mnt_drop_write(filp->f_path.mnt); return err; } case EXT4_IOC_MIGRATE: return ext4_ext_migrate(inode, filp, cmd, arg); 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_IOC_GROUP_ADD: break; default: return -ENOIOCTLCMD; } return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); } #endif