/* * 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/capability.h> #include <linux/time.h> #include <linux/compat.h> #include <linux/mount.h> #include <linux/file.h> #include <linux/random.h> #include <asm/uaccess.h> #include "ext4_jbd2.h" #include "ext4.h" #define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1) /** * Swap memory between @a and @b for @len bytes. * * @a: pointer to first memory area * @b: pointer to second memory area * @len: number of bytes to swap * */ static void memswap(void *a, void *b, size_t len) { unsigned char *ap, *bp; ap = (unsigned char *)a; bp = (unsigned char *)b; while (len-- > 0) { swap(*ap, *bp); ap++; bp++; } } /** * Swap i_data and associated attributes between @inode1 and @inode2. * This function is used for the primary swap between inode1 and inode2 * and also to revert this primary swap in case of errors. * * Therefore you have to make sure, that calling this method twice * will revert all changes. * * @inode1: pointer to first inode * @inode2: pointer to second inode */ static void swap_inode_data(struct inode *inode1, struct inode *inode2) { loff_t isize; struct ext4_inode_info *ei1; struct ext4_inode_info *ei2; ei1 = EXT4_I(inode1); ei2 = EXT4_I(inode2); memswap(&inode1->i_flags, &inode2->i_flags, sizeof(inode1->i_flags)); memswap(&inode1->i_version, &inode2->i_version, sizeof(inode1->i_version)); memswap(&inode1->i_blocks, &inode2->i_blocks, sizeof(inode1->i_blocks)); memswap(&inode1->i_bytes, &inode2->i_bytes, sizeof(inode1->i_bytes)); memswap(&inode1->i_atime, &inode2->i_atime, sizeof(inode1->i_atime)); memswap(&inode1->i_mtime, &inode2->i_mtime, sizeof(inode1->i_mtime)); memswap(ei1->i_data, ei2->i_data, sizeof(ei1->i_data)); memswap(&ei1->i_flags, &ei2->i_flags, sizeof(ei1->i_flags)); memswap(&ei1->i_disksize, &ei2->i_disksize, sizeof(ei1->i_disksize)); ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS); ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS); isize = i_size_read(inode1); i_size_write(inode1, i_size_read(inode2)); i_size_write(inode2, isize); } /** * Swap the information from the given @inode and the inode * EXT4_BOOT_LOADER_INO. It will basically swap i_data and all other * important fields of the inodes. * * @sb: the super block of the filesystem * @inode: the inode to swap with EXT4_BOOT_LOADER_INO * */ static long swap_inode_boot_loader(struct super_block *sb, struct inode *inode) { handle_t *handle; int err; struct inode *inode_bl; struct ext4_inode_info *ei_bl; struct ext4_sb_info *sbi = EXT4_SB(sb); if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode)) return -EINVAL; if (!inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN)) return -EPERM; inode_bl = ext4_iget(sb, EXT4_BOOT_LOADER_INO); if (IS_ERR(inode_bl)) return PTR_ERR(inode_bl); ei_bl = EXT4_I(inode_bl); filemap_flush(inode->i_mapping); filemap_flush(inode_bl->i_mapping); /* Protect orig inodes against a truncate and make sure, * that only 1 swap_inode_boot_loader is running. */ lock_two_nondirectories(inode, inode_bl); truncate_inode_pages(&inode->i_data, 0); truncate_inode_pages(&inode_bl->i_data, 0); /* Wait for all existing dio workers */ ext4_inode_block_unlocked_dio(inode); ext4_inode_block_unlocked_dio(inode_bl); inode_dio_wait(inode); inode_dio_wait(inode_bl); handle = ext4_journal_start(inode_bl, EXT4_HT_MOVE_EXTENTS, 2); if (IS_ERR(handle)) { err = -EINVAL; goto journal_err_out; } /* Protect extent tree against block allocations via delalloc */ ext4_double_down_write_data_sem(inode, inode_bl); if (inode_bl->i_nlink == 0) { /* this inode has never been used as a BOOT_LOADER */ set_nlink(inode_bl, 1); i_uid_write(inode_bl, 0); i_gid_write(inode_bl, 0); inode_bl->i_flags = 0; ei_bl->i_flags = 0; inode_bl->i_version = 1; i_size_write(inode_bl, 0); inode_bl->i_mode = S_IFREG; if (ext4_has_feature_extents(sb)) { ext4_set_inode_flag(inode_bl, EXT4_INODE_EXTENTS); ext4_ext_tree_init(handle, inode_bl); } else memset(ei_bl->i_data, 0, sizeof(ei_bl->i_data)); } swap_inode_data(inode, inode_bl); inode->i_ctime = inode_bl->i_ctime = ext4_current_time(inode); spin_lock(&sbi->s_next_gen_lock); inode->i_generation = sbi->s_next_generation++; inode_bl->i_generation = sbi->s_next_generation++; spin_unlock(&sbi->s_next_gen_lock); ext4_discard_preallocations(inode); err = ext4_mark_inode_dirty(handle, inode); if (err < 0) { ext4_warning(inode->i_sb, "couldn't mark inode #%lu dirty (err %d)", inode->i_ino, err); /* Revert all changes: */ swap_inode_data(inode, inode_bl); } else { err = ext4_mark_inode_dirty(handle, inode_bl); if (err < 0) { ext4_warning(inode_bl->i_sb, "couldn't mark inode #%lu dirty (err %d)", inode_bl->i_ino, err); /* Revert all changes: */ swap_inode_data(inode, inode_bl); ext4_mark_inode_dirty(handle, inode); } } ext4_journal_stop(handle); ext4_double_up_write_data_sem(inode, inode_bl); journal_err_out: ext4_inode_resume_unlocked_dio(inode); ext4_inode_resume_unlocked_dio(inode_bl); unlock_two_nondirectories(inode, inode_bl); iput(inode_bl); return err; } static int uuid_is_zero(__u8 u[16]) { int i; for (i = 0; i < 16; i++) if (u[i]) return 0; return 1; } long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { struct inode *inode = file_inode(filp); struct super_block *sb = inode->i_sb; 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, mask, i; unsigned int jflag; if (!inode_owner_or_capable(inode)) return -EACCES; if (get_user(flags, (int __user *) arg)) return -EFAULT; err = mnt_want_write_file(filp); 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 ((flags ^ oldflags) & EXT4_EXTENTS_FL) migrate = 1; 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, EXT4_HT_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; for (i = 0, mask = 1; i < 32; i++, mask <<= 1) { if (!(mask & EXT4_FL_USER_MODIFIABLE)) continue; if (mask & flags) ext4_set_inode_flag(inode, i); else ext4_clear_inode_flag(inode, i); } 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) { if (flags & EXT4_EXTENTS_FL) err = ext4_ext_migrate(inode); else err = ext4_ind_migrate(inode); } flags_out: mutex_unlock(&inode->i_mutex); mnt_drop_write_file(filp); 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; if (ext4_has_metadata_csum(inode->i_sb)) { ext4_warning(sb, "Setting inode version is not " "supported with metadata_csum enabled."); return -ENOTTY; } err = mnt_want_write_file(filp); if (err) return err; if (get_user(generation, (int __user *) arg)) { err = -EFAULT; goto setversion_out; } mutex_lock(&inode->i_mutex); handle = ext4_journal_start(inode, EXT4_HT_INODE, 1); if (IS_ERR(handle)) { err = PTR_ERR(handle); goto unlock_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); unlock_out: mutex_unlock(&inode->i_mutex); setversion_out: mnt_drop_write_file(filp); return err; } case EXT4_IOC_GROUP_EXTEND: { ext4_fsblk_t n_blocks_count; int err, err2=0; err = ext4_resize_begin(sb); if (err) return err; if (get_user(n_blocks_count, (__u32 __user *)arg)) { err = -EFAULT; goto group_extend_out; } if (ext4_has_feature_bigalloc(sb)) { ext4_msg(sb, KERN_ERR, "Online resizing not supported with bigalloc"); err = -EOPNOTSUPP; goto group_extend_out; } err = mnt_want_write_file(filp); if (err) goto group_extend_out; 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_file(filp); group_extend_out: ext4_resize_end(sb); return err; } case EXT4_IOC_MOVE_EXT: { struct move_extent me; struct fd donor; 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 = fdget(me.donor_fd); if (!donor.file) return -EBADF; if (!(donor.file->f_mode & FMODE_WRITE)) { err = -EBADF; goto mext_out; } if (ext4_has_feature_bigalloc(sb)) { ext4_msg(sb, KERN_ERR, "Online defrag not supported with bigalloc"); err = -EOPNOTSUPP; goto mext_out; } err = mnt_want_write_file(filp); if (err) goto mext_out; err = ext4_move_extents(filp, donor.file, me.orig_start, me.donor_start, me.len, &me.moved_len); mnt_drop_write_file(filp); if (copy_to_user((struct move_extent __user *)arg, &me, sizeof(me))) err = -EFAULT; mext_out: fdput(donor); return err; } case EXT4_IOC_GROUP_ADD: { struct ext4_new_group_data input; int err, err2=0; err = ext4_resize_begin(sb); if (err) return err; if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg, sizeof(input))) { err = -EFAULT; goto group_add_out; } if (ext4_has_feature_bigalloc(sb)) { ext4_msg(sb, KERN_ERR, "Online resizing not supported with bigalloc"); err = -EOPNOTSUPP; goto group_add_out; } err = mnt_want_write_file(filp); if (err) goto group_add_out; 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_file(filp); if (!err && ext4_has_group_desc_csum(sb) && test_opt(sb, INIT_INODE_TABLE)) err = ext4_register_li_request(sb, input.group); group_add_out: ext4_resize_end(sb); return err; } case EXT4_IOC_MIGRATE: { int err; if (!inode_owner_or_capable(inode)) return -EACCES; err = mnt_want_write_file(filp); 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_file(filp); return err; } case EXT4_IOC_ALLOC_DA_BLKS: { int err; if (!inode_owner_or_capable(inode)) return -EACCES; err = mnt_want_write_file(filp); if (err) return err; err = ext4_alloc_da_blocks(inode); mnt_drop_write_file(filp); return err; } case EXT4_IOC_SWAP_BOOT: { int err; if (!(filp->f_mode & FMODE_WRITE)) return -EBADF; err = mnt_want_write_file(filp); if (err) return err; err = swap_inode_boot_loader(sb, inode); mnt_drop_write_file(filp); return err; } case EXT4_IOC_RESIZE_FS: { ext4_fsblk_t n_blocks_count; int err = 0, err2 = 0; ext4_group_t o_group = EXT4_SB(sb)->s_groups_count; if (ext4_has_feature_bigalloc(sb)) { ext4_msg(sb, KERN_ERR, "Online resizing not (yet) supported with bigalloc"); return -EOPNOTSUPP; } if (copy_from_user(&n_blocks_count, (__u64 __user *)arg, sizeof(__u64))) { return -EFAULT; } err = ext4_resize_begin(sb); if (err) return err; err = mnt_want_write_file(filp); if (err) goto resizefs_out; err = ext4_resize_fs(sb, 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_file(filp); if (!err && (o_group > EXT4_SB(sb)->s_groups_count) && ext4_has_group_desc_csum(sb) && test_opt(sb, INIT_INODE_TABLE)) err = ext4_register_li_request(sb, o_group); resizefs_out: ext4_resize_end(sb); return err; } case FIDTRIM: case FITRIM: { struct request_queue *q = bdev_get_queue(sb->s_bdev); struct fstrim_range range; int ret = 0; int flags = cmd == FIDTRIM ? BLKDEV_DISCARD_SECURE : 0; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!blk_queue_discard(q)) return -EOPNOTSUPP; if ((flags & BLKDEV_DISCARD_SECURE) && !blk_queue_secdiscard(q)) return -EOPNOTSUPP; if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range))) return -EFAULT; range.minlen = max((unsigned int)range.minlen, q->limits.discard_granularity); ret = ext4_trim_fs(sb, &range, flags); if (ret < 0) return ret; if (copy_to_user((struct fstrim_range __user *)arg, &range, sizeof(range))) return -EFAULT; return 0; } case EXT4_IOC_PRECACHE_EXTENTS: return ext4_ext_precache(inode); case EXT4_IOC_SET_ENCRYPTION_POLICY: { #ifdef CONFIG_EXT4_FS_ENCRYPTION struct ext4_encryption_policy policy; int err = 0; if (copy_from_user(&policy, (struct ext4_encryption_policy __user *)arg, sizeof(policy))) { err = -EFAULT; goto encryption_policy_out; } err = ext4_process_policy(&policy, inode); encryption_policy_out: return err; #else return -EOPNOTSUPP; #endif } case EXT4_IOC_GET_ENCRYPTION_PWSALT: { int err, err2; struct ext4_sb_info *sbi = EXT4_SB(sb); handle_t *handle; if (!ext4_sb_has_crypto(sb)) return -EOPNOTSUPP; if (uuid_is_zero(sbi->s_es->s_encrypt_pw_salt)) { err = mnt_want_write_file(filp); if (err) return err; handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1); if (IS_ERR(handle)) { err = PTR_ERR(handle); goto pwsalt_err_exit; } err = ext4_journal_get_write_access(handle, sbi->s_sbh); if (err) goto pwsalt_err_journal; generate_random_uuid(sbi->s_es->s_encrypt_pw_salt); err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh); pwsalt_err_journal: err2 = ext4_journal_stop(handle); if (err2 && !err) err = err2; pwsalt_err_exit: mnt_drop_write_file(filp); if (err) return err; } if (copy_to_user((void __user *) arg, sbi->s_es->s_encrypt_pw_salt, 16)) return -EFAULT; return 0; } case EXT4_IOC_GET_ENCRYPTION_POLICY: { #ifdef CONFIG_EXT4_FS_ENCRYPTION struct ext4_encryption_policy policy; int err = 0; if (!ext4_encrypted_inode(inode)) return -ENOENT; err = ext4_get_policy(inode, &policy); if (err) return err; if (copy_to_user((void __user *)arg, &policy, sizeof(policy))) return -EFAULT; return 0; #else return -EOPNOTSUPP; #endif } 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; 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 EXT4_IOC_RESIZE_FS: case EXT4_IOC_PRECACHE_EXTENTS: case EXT4_IOC_SET_ENCRYPTION_POLICY: case EXT4_IOC_GET_ENCRYPTION_PWSALT: case EXT4_IOC_GET_ENCRYPTION_POLICY: break; default: return -ENOIOCTLCMD; } return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); } #endif