/* * Copyright (C) 2007 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License v2 as published by the Free Software Foundation. * * 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 021110-1307, USA. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ctree.h" #include "disk-io.h" #include "transaction.h" #include "btrfs_inode.h" #include "print-tree.h" #include "volumes.h" #include "locking.h" #include "inode-map.h" #include "backref.h" #include "rcu-string.h" #include "send.h" #include "dev-replace.h" #include "props.h" #include "sysfs.h" #include "qgroup.h" #ifdef CONFIG_64BIT /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI * structures are incorrect, as the timespec structure from userspace * is 4 bytes too small. We define these alternatives here to teach * the kernel about the 32-bit struct packing. */ struct btrfs_ioctl_timespec_32 { __u64 sec; __u32 nsec; } __attribute__ ((__packed__)); struct btrfs_ioctl_received_subvol_args_32 { char uuid[BTRFS_UUID_SIZE]; /* in */ __u64 stransid; /* in */ __u64 rtransid; /* out */ struct btrfs_ioctl_timespec_32 stime; /* in */ struct btrfs_ioctl_timespec_32 rtime; /* out */ __u64 flags; /* in */ __u64 reserved[16]; /* in */ } __attribute__ ((__packed__)); #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \ struct btrfs_ioctl_received_subvol_args_32) #endif static int btrfs_clone(struct inode *src, struct inode *inode, u64 off, u64 olen, u64 olen_aligned, u64 destoff); /* Mask out flags that are inappropriate for the given type of inode. */ static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags) { if (S_ISDIR(mode)) return flags; else if (S_ISREG(mode)) return flags & ~FS_DIRSYNC_FL; else return flags & (FS_NODUMP_FL | FS_NOATIME_FL); } /* * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl. */ static unsigned int btrfs_flags_to_ioctl(unsigned int flags) { unsigned int iflags = 0; if (flags & BTRFS_INODE_SYNC) iflags |= FS_SYNC_FL; if (flags & BTRFS_INODE_IMMUTABLE) iflags |= FS_IMMUTABLE_FL; if (flags & BTRFS_INODE_APPEND) iflags |= FS_APPEND_FL; if (flags & BTRFS_INODE_NODUMP) iflags |= FS_NODUMP_FL; if (flags & BTRFS_INODE_NOATIME) iflags |= FS_NOATIME_FL; if (flags & BTRFS_INODE_DIRSYNC) iflags |= FS_DIRSYNC_FL; if (flags & BTRFS_INODE_NODATACOW) iflags |= FS_NOCOW_FL; if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS)) iflags |= FS_COMPR_FL; else if (flags & BTRFS_INODE_NOCOMPRESS) iflags |= FS_NOCOMP_FL; return iflags; } /* * Update inode->i_flags based on the btrfs internal flags. */ void btrfs_update_iflags(struct inode *inode) { struct btrfs_inode *ip = BTRFS_I(inode); unsigned int new_fl = 0; if (ip->flags & BTRFS_INODE_SYNC) new_fl |= S_SYNC; if (ip->flags & BTRFS_INODE_IMMUTABLE) new_fl |= S_IMMUTABLE; if (ip->flags & BTRFS_INODE_APPEND) new_fl |= S_APPEND; if (ip->flags & BTRFS_INODE_NOATIME) new_fl |= S_NOATIME; if (ip->flags & BTRFS_INODE_DIRSYNC) new_fl |= S_DIRSYNC; set_mask_bits(&inode->i_flags, S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC, new_fl); } /* * Inherit flags from the parent inode. * * Currently only the compression flags and the cow flags are inherited. */ void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) { unsigned int flags; if (!dir) return; flags = BTRFS_I(dir)->flags; if (flags & BTRFS_INODE_NOCOMPRESS) { BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS; BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; } else if (flags & BTRFS_INODE_COMPRESS) { BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS; BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS; } if (flags & BTRFS_INODE_NODATACOW) { BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; if (S_ISREG(inode->i_mode)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; } btrfs_update_iflags(inode); } static int btrfs_ioctl_getflags(struct file *file, void __user *arg) { struct btrfs_inode *ip = BTRFS_I(file_inode(file)); unsigned int flags = btrfs_flags_to_ioctl(ip->flags); if (copy_to_user(arg, &flags, sizeof(flags))) return -EFAULT; return 0; } static int check_flags(unsigned int flags) { if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ FS_NOATIME_FL | FS_NODUMP_FL | \ FS_SYNC_FL | FS_DIRSYNC_FL | \ FS_NOCOMP_FL | FS_COMPR_FL | FS_NOCOW_FL)) return -EOPNOTSUPP; if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) return -EINVAL; return 0; } static int btrfs_ioctl_setflags(struct file *file, void __user *arg) { struct inode *inode = file_inode(file); struct btrfs_inode *ip = BTRFS_I(inode); struct btrfs_root *root = ip->root; struct btrfs_trans_handle *trans; unsigned int flags, oldflags; int ret; u64 ip_oldflags; unsigned int i_oldflags; umode_t mode; if (!inode_owner_or_capable(inode)) return -EPERM; if (btrfs_root_readonly(root)) return -EROFS; if (copy_from_user(&flags, arg, sizeof(flags))) return -EFAULT; ret = check_flags(flags); if (ret) return ret; ret = mnt_want_write_file(file); if (ret) return ret; mutex_lock(&inode->i_mutex); ip_oldflags = ip->flags; i_oldflags = inode->i_flags; mode = inode->i_mode; flags = btrfs_mask_flags(inode->i_mode, flags); oldflags = btrfs_flags_to_ioctl(ip->flags); if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { if (!capable(CAP_LINUX_IMMUTABLE)) { ret = -EPERM; goto out_unlock; } } if (flags & FS_SYNC_FL) ip->flags |= BTRFS_INODE_SYNC; else ip->flags &= ~BTRFS_INODE_SYNC; if (flags & FS_IMMUTABLE_FL) ip->flags |= BTRFS_INODE_IMMUTABLE; else ip->flags &= ~BTRFS_INODE_IMMUTABLE; if (flags & FS_APPEND_FL) ip->flags |= BTRFS_INODE_APPEND; else ip->flags &= ~BTRFS_INODE_APPEND; if (flags & FS_NODUMP_FL) ip->flags |= BTRFS_INODE_NODUMP; else ip->flags &= ~BTRFS_INODE_NODUMP; if (flags & FS_NOATIME_FL) ip->flags |= BTRFS_INODE_NOATIME; else ip->flags &= ~BTRFS_INODE_NOATIME; if (flags & FS_DIRSYNC_FL) ip->flags |= BTRFS_INODE_DIRSYNC; else ip->flags &= ~BTRFS_INODE_DIRSYNC; if (flags & FS_NOCOW_FL) { if (S_ISREG(mode)) { /* * It's safe to turn csums off here, no extents exist. * Otherwise we want the flag to reflect the real COW * status of the file and will not set it. */ if (inode->i_size == 0) ip->flags |= BTRFS_INODE_NODATACOW | BTRFS_INODE_NODATASUM; } else { ip->flags |= BTRFS_INODE_NODATACOW; } } else { /* * Revert back under same assuptions as above */ if (S_ISREG(mode)) { if (inode->i_size == 0) ip->flags &= ~(BTRFS_INODE_NODATACOW | BTRFS_INODE_NODATASUM); } else { ip->flags &= ~BTRFS_INODE_NODATACOW; } } /* * The COMPRESS flag can only be changed by users, while the NOCOMPRESS * flag may be changed automatically if compression code won't make * things smaller. */ if (flags & FS_NOCOMP_FL) { ip->flags &= ~BTRFS_INODE_COMPRESS; ip->flags |= BTRFS_INODE_NOCOMPRESS; ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0); if (ret && ret != -ENODATA) goto out_drop; } else if (flags & FS_COMPR_FL) { const char *comp; ip->flags |= BTRFS_INODE_COMPRESS; ip->flags &= ~BTRFS_INODE_NOCOMPRESS; if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO) comp = "lzo"; else comp = "zlib"; ret = btrfs_set_prop(inode, "btrfs.compression", comp, strlen(comp), 0); if (ret) goto out_drop; } else { ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0); if (ret && ret != -ENODATA) goto out_drop; ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); } trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_drop; } btrfs_update_iflags(inode); inode_inc_iversion(inode); inode->i_ctime = CURRENT_TIME; ret = btrfs_update_inode(trans, root, inode); btrfs_end_transaction(trans, root); out_drop: if (ret) { ip->flags = ip_oldflags; inode->i_flags = i_oldflags; } out_unlock: mutex_unlock(&inode->i_mutex); mnt_drop_write_file(file); return ret; } static int btrfs_ioctl_getversion(struct file *file, int __user *arg) { struct inode *inode = file_inode(file); return put_user(inode->i_generation, arg); } static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) { struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb); struct btrfs_device *device; struct request_queue *q; struct fstrim_range range; u64 minlen = ULLONG_MAX; u64 num_devices = 0; u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy); int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; rcu_read_lock(); list_for_each_entry_rcu(device, &fs_info->fs_devices->devices, dev_list) { if (!device->bdev) continue; q = bdev_get_queue(device->bdev); if (blk_queue_discard(q)) { num_devices++; minlen = min((u64)q->limits.discard_granularity, minlen); } } rcu_read_unlock(); if (!num_devices) return -EOPNOTSUPP; if (copy_from_user(&range, arg, sizeof(range))) return -EFAULT; if (range.start > total_bytes || range.len < fs_info->sb->s_blocksize) return -EINVAL; range.len = min(range.len, total_bytes - range.start); range.minlen = max(range.minlen, minlen); ret = btrfs_trim_fs(fs_info->tree_root, &range); if (ret < 0) return ret; if (copy_to_user(arg, &range, sizeof(range))) return -EFAULT; return 0; } int btrfs_is_empty_uuid(u8 *uuid) { int i; for (i = 0; i < BTRFS_UUID_SIZE; i++) { if (uuid[i]) return 0; } return 1; } static noinline int create_subvol(struct inode *dir, struct dentry *dentry, char *name, int namelen, u64 *async_transid, struct btrfs_qgroup_inherit *inherit) { struct btrfs_trans_handle *trans; struct btrfs_key key; struct btrfs_root_item root_item; struct btrfs_inode_item *inode_item; struct extent_buffer *leaf; struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_root *new_root; struct btrfs_block_rsv block_rsv; struct timespec cur_time = CURRENT_TIME; struct inode *inode; int ret; int err; u64 objectid; u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; u64 index = 0; u64 qgroup_reserved; uuid_le new_uuid; ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid); if (ret) return ret; btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); /* * The same as the snapshot creation, please see the comment * of create_snapshot(). */ ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, &qgroup_reserved, false); if (ret) return ret; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); return ret; } trans->block_rsv = &block_rsv; trans->bytes_reserved = block_rsv.size; ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit); if (ret) goto fail; leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0); if (IS_ERR(leaf)) { ret = PTR_ERR(leaf); goto fail; } memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header)); btrfs_set_header_bytenr(leaf, leaf->start); btrfs_set_header_generation(leaf, trans->transid); btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV); btrfs_set_header_owner(leaf, objectid); write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE); write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, btrfs_header_chunk_tree_uuid(leaf), BTRFS_UUID_SIZE); btrfs_mark_buffer_dirty(leaf); memset(&root_item, 0, sizeof(root_item)); inode_item = &root_item.inode; btrfs_set_stack_inode_generation(inode_item, 1); btrfs_set_stack_inode_size(inode_item, 3); btrfs_set_stack_inode_nlink(inode_item, 1); btrfs_set_stack_inode_nbytes(inode_item, root->nodesize); btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); btrfs_set_root_flags(&root_item, 0); btrfs_set_root_limit(&root_item, 0); btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT); btrfs_set_root_bytenr(&root_item, leaf->start); btrfs_set_root_generation(&root_item, trans->transid); btrfs_set_root_level(&root_item, 0); btrfs_set_root_refs(&root_item, 1); btrfs_set_root_used(&root_item, leaf->len); btrfs_set_root_last_snapshot(&root_item, 0); btrfs_set_root_generation_v2(&root_item, btrfs_root_generation(&root_item)); uuid_le_gen(&new_uuid); memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE); btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec); btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec); root_item.ctime = root_item.otime; btrfs_set_root_ctransid(&root_item, trans->transid); btrfs_set_root_otransid(&root_item, trans->transid); btrfs_tree_unlock(leaf); free_extent_buffer(leaf); leaf = NULL; btrfs_set_root_dirid(&root_item, new_dirid); key.objectid = objectid; key.offset = 0; key.type = BTRFS_ROOT_ITEM_KEY; ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, &root_item); if (ret) goto fail; key.offset = (u64)-1; new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); if (IS_ERR(new_root)) { btrfs_abort_transaction(trans, root, PTR_ERR(new_root)); ret = PTR_ERR(new_root); goto fail; } btrfs_record_root_in_trans(trans, new_root); ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid); if (ret) { /* We potentially lose an unused inode item here */ btrfs_abort_transaction(trans, root, ret); goto fail; } /* * insert the directory item */ ret = btrfs_set_inode_index(dir, &index); if (ret) { btrfs_abort_transaction(trans, root, ret); goto fail; } ret = btrfs_insert_dir_item(trans, root, name, namelen, dir, &key, BTRFS_FT_DIR, index); if (ret) { btrfs_abort_transaction(trans, root, ret); goto fail; } btrfs_i_size_write(dir, dir->i_size + namelen * 2); ret = btrfs_update_inode(trans, root, dir); BUG_ON(ret); ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, objectid, root->root_key.objectid, btrfs_ino(dir), index, name, namelen); BUG_ON(ret); ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root, root_item.uuid, BTRFS_UUID_KEY_SUBVOL, objectid); if (ret) btrfs_abort_transaction(trans, root, ret); fail: trans->block_rsv = NULL; trans->bytes_reserved = 0; btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); if (async_transid) { *async_transid = trans->transid; err = btrfs_commit_transaction_async(trans, root, 1); if (err) err = btrfs_commit_transaction(trans, root); } else { err = btrfs_commit_transaction(trans, root); } if (err && !ret) ret = err; if (!ret) { inode = btrfs_lookup_dentry(dir, dentry); if (IS_ERR(inode)) return PTR_ERR(inode); d_instantiate(dentry, inode); } return ret; } static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root) { s64 writers; DEFINE_WAIT(wait); do { prepare_to_wait(&root->subv_writers->wait, &wait, TASK_UNINTERRUPTIBLE); writers = percpu_counter_sum(&root->subv_writers->counter); if (writers) schedule(); finish_wait(&root->subv_writers->wait, &wait); } while (writers); } static int create_snapshot(struct btrfs_root *root, struct inode *dir, struct dentry *dentry, char *name, int namelen, u64 *async_transid, bool readonly, struct btrfs_qgroup_inherit *inherit) { struct inode *inode; struct btrfs_pending_snapshot *pending_snapshot; struct btrfs_trans_handle *trans; int ret; if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) return -EINVAL; atomic_inc(&root->will_be_snapshoted); smp_mb__after_atomic(); btrfs_wait_for_no_snapshoting_writes(root); ret = btrfs_start_delalloc_inodes(root, 0); if (ret) goto out; btrfs_wait_ordered_extents(root, -1); pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); if (!pending_snapshot) { ret = -ENOMEM; goto out; } btrfs_init_block_rsv(&pending_snapshot->block_rsv, BTRFS_BLOCK_RSV_TEMP); /* * 1 - parent dir inode * 2 - dir entries * 1 - root item * 2 - root ref/backref * 1 - root of snapshot * 1 - UUID item */ ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, &pending_snapshot->block_rsv, 8, &pending_snapshot->qgroup_reserved, false); if (ret) goto free; pending_snapshot->dentry = dentry; pending_snapshot->root = root; pending_snapshot->readonly = readonly; pending_snapshot->dir = dir; pending_snapshot->inherit = inherit; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto fail; } spin_lock(&root->fs_info->trans_lock); list_add(&pending_snapshot->list, &trans->transaction->pending_snapshots); spin_unlock(&root->fs_info->trans_lock); if (async_transid) { *async_transid = trans->transid; ret = btrfs_commit_transaction_async(trans, root->fs_info->extent_root, 1); if (ret) ret = btrfs_commit_transaction(trans, root); } else { ret = btrfs_commit_transaction(trans, root->fs_info->extent_root); } if (ret) goto fail; ret = pending_snapshot->error; if (ret) goto fail; ret = btrfs_orphan_cleanup(pending_snapshot->snap); if (ret) goto fail; inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry); if (IS_ERR(inode)) { ret = PTR_ERR(inode); goto fail; } d_instantiate(dentry, inode); ret = 0; fail: btrfs_subvolume_release_metadata(BTRFS_I(dir)->root, &pending_snapshot->block_rsv, pending_snapshot->qgroup_reserved); free: kfree(pending_snapshot); out: if (atomic_dec_and_test(&root->will_be_snapshoted)) wake_up_atomic_t(&root->will_be_snapshoted); return ret; } /* copy of may_delete in fs/namei.c() * Check whether we can remove a link victim from directory dir, check * whether the type of victim is right. * 1. We can't do it if dir is read-only (done in permission()) * 2. We should have write and exec permissions on dir * 3. We can't remove anything from append-only dir * 4. We can't do anything with immutable dir (done in permission()) * 5. If the sticky bit on dir is set we should either * a. be owner of dir, or * b. be owner of victim, or * c. have CAP_FOWNER capability * 6. If the victim is append-only or immutable we can't do antyhing with * links pointing to it. * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. * 9. We can't remove a root or mountpoint. * 10. We don't allow removal of NFS sillyrenamed files; it's handled by * nfs_async_unlink(). */ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir) { int error; if (!victim->d_inode) return -ENOENT; BUG_ON(victim->d_parent->d_inode != dir); audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); error = inode_permission(dir, MAY_WRITE | MAY_EXEC); if (error) return error; if (IS_APPEND(dir)) return -EPERM; if (check_sticky(dir, victim->d_inode) || IS_APPEND(victim->d_inode) || IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) return -EPERM; if (isdir) { if (!d_is_dir(victim)) return -ENOTDIR; if (IS_ROOT(victim)) return -EBUSY; } else if (d_is_dir(victim)) return -EISDIR; if (IS_DEADDIR(dir)) return -ENOENT; if (victim->d_flags & DCACHE_NFSFS_RENAMED) return -EBUSY; return 0; } /* copy of may_create in fs/namei.c() */ static inline int btrfs_may_create(struct inode *dir, struct dentry *child) { if (child->d_inode) return -EEXIST; if (IS_DEADDIR(dir)) return -ENOENT; return inode_permission(dir, MAY_WRITE | MAY_EXEC); } /* * Create a new subvolume below @parent. This is largely modeled after * sys_mkdirat and vfs_mkdir, but we only do a single component lookup * inside this filesystem so it's quite a bit simpler. */ static noinline int btrfs_mksubvol(struct path *parent, char *name, int namelen, struct btrfs_root *snap_src, u64 *async_transid, bool readonly, struct btrfs_qgroup_inherit *inherit) { struct inode *dir = parent->dentry->d_inode; struct dentry *dentry; int error; error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT); if (error == -EINTR) return error; dentry = lookup_one_len(name, parent->dentry, namelen); error = PTR_ERR(dentry); if (IS_ERR(dentry)) goto out_unlock; error = -EEXIST; if (dentry->d_inode) goto out_dput; error = btrfs_may_create(dir, dentry); if (error) goto out_dput; /* * even if this name doesn't exist, we may get hash collisions. * check for them now when we can safely fail */ error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root, dir->i_ino, name, namelen); if (error) goto out_dput; down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) goto out_up_read; if (snap_src) { error = create_snapshot(snap_src, dir, dentry, name, namelen, async_transid, readonly, inherit); } else { error = create_subvol(dir, dentry, name, namelen, async_transid, inherit); } if (!error) fsnotify_mkdir(dir, dentry); out_up_read: up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); out_dput: dput(dentry); out_unlock: mutex_unlock(&dir->i_mutex); return error; } /* * When we're defragging a range, we don't want to kick it off again * if it is really just waiting for delalloc to send it down. * If we find a nice big extent or delalloc range for the bytes in the * file you want to defrag, we return 0 to let you know to skip this * part of the file */ static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh) { struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_map *em = NULL; struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; u64 end; read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); read_unlock(&em_tree->lock); if (em) { end = extent_map_end(em); free_extent_map(em); if (end - offset > thresh) return 0; } /* if we already have a nice delalloc here, just stop */ thresh /= 2; end = count_range_bits(io_tree, &offset, offset + thresh, thresh, EXTENT_DELALLOC, 1); if (end >= thresh) return 0; return 1; } /* * helper function to walk through a file and find extents * newer than a specific transid, and smaller than thresh. * * This is used by the defragging code to find new and small * extents */ static int find_new_extents(struct btrfs_root *root, struct inode *inode, u64 newer_than, u64 *off, u32 thresh) { struct btrfs_path *path; struct btrfs_key min_key; struct extent_buffer *leaf; struct btrfs_file_extent_item *extent; int type; int ret; u64 ino = btrfs_ino(inode); path = btrfs_alloc_path(); if (!path) return -ENOMEM; min_key.objectid = ino; min_key.type = BTRFS_EXTENT_DATA_KEY; min_key.offset = *off; while (1) { ret = btrfs_search_forward(root, &min_key, path, newer_than); if (ret != 0) goto none; process_slot: if (min_key.objectid != ino) goto none; if (min_key.type != BTRFS_EXTENT_DATA_KEY) goto none; leaf = path->nodes[0]; extent = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); type = btrfs_file_extent_type(leaf, extent); if (type == BTRFS_FILE_EXTENT_REG && btrfs_file_extent_num_bytes(leaf, extent) < thresh && check_defrag_in_cache(inode, min_key.offset, thresh)) { *off = min_key.offset; btrfs_free_path(path); return 0; } path->slots[0]++; if (path->slots[0] < btrfs_header_nritems(leaf)) { btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]); goto process_slot; } if (min_key.offset == (u64)-1) goto none; min_key.offset++; btrfs_release_path(path); } none: btrfs_free_path(path); return -ENOENT; } static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start) { struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_map *em; u64 len = PAGE_CACHE_SIZE; /* * hopefully we have this extent in the tree already, try without * the full extent lock */ read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, start, len); read_unlock(&em_tree->lock); if (!em) { struct extent_state *cached = NULL; u64 end = start + len - 1; /* get the big lock and read metadata off disk */ lock_extent_bits(io_tree, start, end, 0, &cached); em = btrfs_get_extent(inode, NULL, 0, start, len, 0); unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS); if (IS_ERR(em)) return NULL; } return em; } static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) { struct extent_map *next; bool ret = true; /* this is the last extent */ if (em->start + em->len >= i_size_read(inode)) return false; next = defrag_lookup_extent(inode, em->start + em->len); if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) ret = false; else if ((em->block_start + em->block_len == next->block_start) && (em->block_len > 128 * 1024 && next->block_len > 128 * 1024)) ret = false; free_extent_map(next); return ret; } static int should_defrag_range(struct inode *inode, u64 start, u32 thresh, u64 *last_len, u64 *skip, u64 *defrag_end, int compress) { struct extent_map *em; int ret = 1; bool next_mergeable = true; /* * make sure that once we start defragging an extent, we keep on * defragging it */ if (start < *defrag_end) return 1; *skip = 0; em = defrag_lookup_extent(inode, start); if (!em) return 0; /* this will cover holes, and inline extents */ if (em->block_start >= EXTENT_MAP_LAST_BYTE) { ret = 0; goto out; } next_mergeable = defrag_check_next_extent(inode, em); /* * we hit a real extent, if it is big or the next extent is not a * real extent, don't bother defragging it */ if (!compress && (*last_len == 0 || *last_len >= thresh) && (em->len >= thresh || !next_mergeable)) ret = 0; out: /* * last_len ends up being a counter of how many bytes we've defragged. * every time we choose not to defrag an extent, we reset *last_len * so that the next tiny extent will force a defrag. * * The end result of this is that tiny extents before a single big * extent will force at least part of that big extent to be defragged. */ if (ret) { *defrag_end = extent_map_end(em); } else { *last_len = 0; *skip = extent_map_end(em); *defrag_end = 0; } free_extent_map(em); return ret; } /* * it doesn't do much good to defrag one or two pages * at a time. This pulls in a nice chunk of pages * to COW and defrag. * * It also makes sure the delalloc code has enough * dirty data to avoid making new small extents as part * of the defrag * * It's a good idea to start RA on this range * before calling this. */ static int cluster_pages_for_defrag(struct inode *inode, struct page **pages, unsigned long start_index, unsigned long num_pages) { unsigned long file_end; u64 isize = i_size_read(inode); u64 page_start; u64 page_end; u64 page_cnt; int ret; int i; int i_done; struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; struct extent_io_tree *tree; gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); file_end = (isize - 1) >> PAGE_CACHE_SHIFT; if (!isize || start_index > file_end) return 0; page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); ret = btrfs_delalloc_reserve_space(inode, page_cnt << PAGE_CACHE_SHIFT); if (ret) return ret; i_done = 0; tree = &BTRFS_I(inode)->io_tree; /* step one, lock all the pages */ for (i = 0; i < page_cnt; i++) { struct page *page; again: page = find_or_create_page(inode->i_mapping, start_index + i, mask); if (!page) break; page_start = page_offset(page); page_end = page_start + PAGE_CACHE_SIZE - 1; while (1) { lock_extent_bits(tree, page_start, page_end, 0, &cached_state); ordered = btrfs_lookup_ordered_extent(inode, page_start); unlock_extent_cached(tree, page_start, page_end, &cached_state, GFP_NOFS); if (!ordered) break; unlock_page(page); btrfs_start_ordered_extent(inode, ordered, 1); btrfs_put_ordered_extent(ordered); lock_page(page); /* * we unlocked the page above, so we need check if * it was released or not. */ if (page->mapping != inode->i_mapping) { unlock_page(page); page_cache_release(page); goto again; } } if (!PageUptodate(page)) { btrfs_readpage(NULL, page); lock_page(page); if (!PageUptodate(page)) { unlock_page(page); page_cache_release(page); ret = -EIO; break; } } if (page->mapping != inode->i_mapping) { unlock_page(page); page_cache_release(page); goto again; } pages[i] = page; i_done++; } if (!i_done || ret) goto out; if (!(inode->i_sb->s_flags & MS_ACTIVE)) goto out; /* * so now we have a nice long stream of locked * and up to date pages, lets wait on them */ for (i = 0; i < i_done; i++) wait_on_page_writeback(pages[i]); page_start = page_offset(pages[0]); page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, 0, &cached_state); clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, &cached_state, GFP_NOFS); if (i_done != page_cnt) { spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->outstanding_extents++; spin_unlock(&BTRFS_I(inode)->lock); btrfs_delalloc_release_space(inode, (page_cnt - i_done) << PAGE_CACHE_SHIFT); } set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, &cached_state, GFP_NOFS); unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, &cached_state, GFP_NOFS); for (i = 0; i < i_done; i++) { clear_page_dirty_for_io(pages[i]); ClearPageChecked(pages[i]); set_page_extent_mapped(pages[i]); set_page_dirty(pages[i]); unlock_page(pages[i]); page_cache_release(pages[i]); } return i_done; out: for (i = 0; i < i_done; i++) { unlock_page(pages[i]); page_cache_release(pages[i]); } btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT); return ret; } int btrfs_defrag_file(struct inode *inode, struct file *file, struct btrfs_ioctl_defrag_range_args *range, u64 newer_than, unsigned long max_to_defrag) { struct btrfs_root *root = BTRFS_I(inode)->root; struct file_ra_state *ra = NULL; unsigned long last_index; u64 isize = i_size_read(inode); u64 last_len = 0; u64 skip = 0; u64 defrag_end = 0; u64 newer_off = range->start; unsigned long i; unsigned long ra_index = 0; int ret; int defrag_count = 0; int compress_type = BTRFS_COMPRESS_ZLIB; u32 extent_thresh = range->extent_thresh; unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; unsigned long cluster = max_cluster; u64 new_align = ~((u64)128 * 1024 - 1); struct page **pages = NULL; if (isize == 0) return 0; if (range->start >= isize) return -EINVAL; if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { if (range->compress_type > BTRFS_COMPRESS_TYPES) return -EINVAL; if (range->compress_type) compress_type = range->compress_type; } if (extent_thresh == 0) extent_thresh = 256 * 1024; /* * if we were not given a file, allocate a readahead * context */ if (!file) { ra = kzalloc(sizeof(*ra), GFP_NOFS); if (!ra) return -ENOMEM; file_ra_state_init(ra, inode->i_mapping); } else { ra = &file->f_ra; } pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_NOFS); if (!pages) { ret = -ENOMEM; goto out_ra; } /* find the last page to defrag */ if (range->start + range->len > range->start) { last_index = min_t(u64, isize - 1, range->start + range->len - 1) >> PAGE_CACHE_SHIFT; } else { last_index = (isize - 1) >> PAGE_CACHE_SHIFT; } if (newer_than) { ret = find_new_extents(root, inode, newer_than, &newer_off, 64 * 1024); if (!ret) { range->start = newer_off; /* * we always align our defrag to help keep * the extents in the file evenly spaced */ i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; } else goto out_ra; } else { i = range->start >> PAGE_CACHE_SHIFT; } if (!max_to_defrag) max_to_defrag = last_index + 1; /* * make writeback starts from i, so the defrag range can be * written sequentially. */ if (i < inode->i_mapping->writeback_index) inode->i_mapping->writeback_index = i; while (i <= last_index && defrag_count < max_to_defrag && (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) { /* * make sure we stop running if someone unmounts * the FS */ if (!(inode->i_sb->s_flags & MS_ACTIVE)) break; if (btrfs_defrag_cancelled(root->fs_info)) { printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n"); ret = -EAGAIN; break; } if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, extent_thresh, &last_len, &skip, &defrag_end, range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { unsigned long next; /* * the should_defrag function tells us how much to skip * bump our counter by the suggested amount */ next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE); i = max(i + 1, next); continue; } if (!newer_than) { cluster = (PAGE_CACHE_ALIGN(defrag_end) >> PAGE_CACHE_SHIFT) - i; cluster = min(cluster, max_cluster); } else { cluster = max_cluster; } if (i + cluster > ra_index) { ra_index = max(i, ra_index); btrfs_force_ra(inode->i_mapping, ra, file, ra_index, cluster); ra_index += max_cluster; } mutex_lock(&inode->i_mutex); if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) BTRFS_I(inode)->force_compress = compress_type; ret = cluster_pages_for_defrag(inode, pages, i, cluster); if (ret < 0) { mutex_unlock(&inode->i_mutex); goto out_ra; } defrag_count += ret; balance_dirty_pages_ratelimited(inode->i_mapping); mutex_unlock(&inode->i_mutex); if (newer_than) { if (newer_off == (u64)-1) break; if (ret > 0) i += ret; newer_off = max(newer_off + 1, (u64)i << PAGE_CACHE_SHIFT); ret = find_new_extents(root, inode, newer_than, &newer_off, 64 * 1024); if (!ret) { range->start = newer_off; i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; } else { break; } } else { if (ret > 0) { i += ret; last_len += ret << PAGE_CACHE_SHIFT; } else { i++; last_len = 0; } } } if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) { filemap_flush(inode->i_mapping); if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &BTRFS_I(inode)->runtime_flags)) filemap_flush(inode->i_mapping); } if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { /* the filemap_flush will queue IO into the worker threads, but * we have to make sure the IO is actually started and that * ordered extents get created before we return */ atomic_inc(&root->fs_info->async_submit_draining); while (atomic_read(&root->fs_info->nr_async_submits) || atomic_read(&root->fs_info->async_delalloc_pages)) { wait_event(root->fs_info->async_submit_wait, (atomic_read(&root->fs_info->nr_async_submits) == 0 && atomic_read(&root->fs_info->async_delalloc_pages) == 0)); } atomic_dec(&root->fs_info->async_submit_draining); } if (range->compress_type == BTRFS_COMPRESS_LZO) { btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO); } ret = defrag_count; out_ra: if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { mutex_lock(&inode->i_mutex); BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; mutex_unlock(&inode->i_mutex); } if (!file) kfree(ra); kfree(pages); return ret; } static noinline int btrfs_ioctl_resize(struct file *file, void __user *arg) { u64 new_size; u64 old_size; u64 devid = 1; struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_vol_args *vol_args; struct btrfs_trans_handle *trans; struct btrfs_device *device = NULL; char *sizestr; char *retptr; char *devstr = NULL; int ret = 0; int mod = 0; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1)) { mnt_drop_write_file(file); return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; } mutex_lock(&root->fs_info->volume_mutex); vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) { ret = PTR_ERR(vol_args); goto out; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; sizestr = vol_args->name; devstr = strchr(sizestr, ':'); if (devstr) { sizestr = devstr + 1; *devstr = '\0'; devstr = vol_args->name; ret = kstrtoull(devstr, 10, &devid); if (ret) goto out_free; if (!devid) { ret = -EINVAL; goto out_free; } btrfs_info(root->fs_info, "resizing devid %llu", devid); } device = btrfs_find_device(root->fs_info, devid, NULL, NULL); if (!device) { btrfs_info(root->fs_info, "resizer unable to find device %llu", devid); ret = -ENODEV; goto out_free; } if (!device->writeable) { btrfs_info(root->fs_info, "resizer unable to apply on readonly device %llu", devid); ret = -EPERM; goto out_free; } if (!strcmp(sizestr, "max")) new_size = device->bdev->bd_inode->i_size; else { if (sizestr[0] == '-') { mod = -1; sizestr++; } else if (sizestr[0] == '+') { mod = 1; sizestr++; } new_size = memparse(sizestr, &retptr); if (*retptr != '\0' || new_size == 0) { ret = -EINVAL; goto out_free; } } if (device->is_tgtdev_for_dev_replace) { ret = -EPERM; goto out_free; } old_size = btrfs_device_get_total_bytes(device); if (mod < 0) { if (new_size > old_size) { ret = -EINVAL; goto out_free; } new_size = old_size - new_size; } else if (mod > 0) { if (new_size > ULLONG_MAX - old_size) { ret = -ERANGE; goto out_free; } new_size = old_size + new_size; } if (new_size < 256 * 1024 * 1024) { ret = -EINVAL; goto out_free; } if (new_size > device->bdev->bd_inode->i_size) { ret = -EFBIG; goto out_free; } do_div(new_size, root->sectorsize); new_size *= root->sectorsize; printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n", rcu_str_deref(device->name), new_size); if (new_size > old_size) { trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_free; } ret = btrfs_grow_device(trans, device, new_size); btrfs_commit_transaction(trans, root); } else if (new_size < old_size) { ret = btrfs_shrink_device(device, new_size); } /* equal, nothing need to do */ out_free: kfree(vol_args); out: mutex_unlock(&root->fs_info->volume_mutex); atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); mnt_drop_write_file(file); return ret; } static noinline int btrfs_ioctl_snap_create_transid(struct file *file, char *name, unsigned long fd, int subvol, u64 *transid, bool readonly, struct btrfs_qgroup_inherit *inherit) { int namelen; int ret = 0; ret = mnt_want_write_file(file); if (ret) goto out; namelen = strlen(name); if (strchr(name, '/')) { ret = -EINVAL; goto out_drop_write; } if (name[0] == '.' && (namelen == 1 || (name[1] == '.' && namelen == 2))) { ret = -EEXIST; goto out_drop_write; } if (subvol) { ret = btrfs_mksubvol(&file->f_path, name, namelen, NULL, transid, readonly, inherit); } else { struct fd src = fdget(fd); struct inode *src_inode; if (!src.file) { ret = -EINVAL; goto out_drop_write; } src_inode = file_inode(src.file); if (src_inode->i_sb != file_inode(file)->i_sb) { btrfs_info(BTRFS_I(src_inode)->root->fs_info, "Snapshot src from another FS"); ret = -EXDEV; } else if (!inode_owner_or_capable(src_inode)) { /* * Subvolume creation is not restricted, but snapshots * are limited to own subvolumes only */ ret = -EPERM; } else { ret = btrfs_mksubvol(&file->f_path, name, namelen, BTRFS_I(src_inode)->root, transid, readonly, inherit); } fdput(src); } out_drop_write: mnt_drop_write_file(file); out: return ret; } static noinline int btrfs_ioctl_snap_create(struct file *file, void __user *arg, int subvol) { struct btrfs_ioctl_vol_args *vol_args; int ret; vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) return PTR_ERR(vol_args); vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, vol_args->fd, subvol, NULL, false, NULL); kfree(vol_args); return ret; } static noinline int btrfs_ioctl_snap_create_v2(struct file *file, void __user *arg, int subvol) { struct btrfs_ioctl_vol_args_v2 *vol_args; int ret; u64 transid = 0; u64 *ptr = NULL; bool readonly = false; struct btrfs_qgroup_inherit *inherit = NULL; vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) return PTR_ERR(vol_args); vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; if (vol_args->flags & ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | BTRFS_SUBVOL_QGROUP_INHERIT)) { ret = -EOPNOTSUPP; goto free_args; } if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) ptr = &transid; if (vol_args->flags & BTRFS_SUBVOL_RDONLY) readonly = true; if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { if (vol_args->size > PAGE_CACHE_SIZE) { ret = -EINVAL; goto free_args; } inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); if (IS_ERR(inherit)) { ret = PTR_ERR(inherit); goto free_args; } } ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, vol_args->fd, subvol, ptr, readonly, inherit); if (ret) goto free_inherit; if (ptr && copy_to_user(arg + offsetof(struct btrfs_ioctl_vol_args_v2, transid), ptr, sizeof(*ptr))) ret = -EFAULT; free_inherit: kfree(inherit); free_args: kfree(vol_args); return ret; } static noinline int btrfs_ioctl_subvol_getflags(struct file *file, void __user *arg) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; int ret = 0; u64 flags = 0; if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) return -EINVAL; down_read(&root->fs_info->subvol_sem); if (btrfs_root_readonly(root)) flags |= BTRFS_SUBVOL_RDONLY; up_read(&root->fs_info->subvol_sem); if (copy_to_user(arg, &flags, sizeof(flags))) ret = -EFAULT; return ret; } static noinline int btrfs_ioctl_subvol_setflags(struct file *file, void __user *arg) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; u64 root_flags; u64 flags; int ret = 0; if (!inode_owner_or_capable(inode)) return -EPERM; ret = mnt_want_write_file(file); if (ret) goto out; if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { ret = -EINVAL; goto out_drop_write; } if (copy_from_user(&flags, arg, sizeof(flags))) { ret = -EFAULT; goto out_drop_write; } if (flags & BTRFS_SUBVOL_CREATE_ASYNC) { ret = -EINVAL; goto out_drop_write; } if (flags & ~BTRFS_SUBVOL_RDONLY) { ret = -EOPNOTSUPP; goto out_drop_write; } down_write(&root->fs_info->subvol_sem); /* nothing to do */ if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) goto out_drop_sem; root_flags = btrfs_root_flags(&root->root_item); if (flags & BTRFS_SUBVOL_RDONLY) { btrfs_set_root_flags(&root->root_item, root_flags | BTRFS_ROOT_SUBVOL_RDONLY); } else { /* * Block RO -> RW transition if this subvolume is involved in * send */ spin_lock(&root->root_item_lock); if (root->send_in_progress == 0) { btrfs_set_root_flags(&root->root_item, root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); spin_unlock(&root->root_item_lock); } else { spin_unlock(&root->root_item_lock); btrfs_warn(root->fs_info, "Attempt to set subvolume %llu read-write during send", root->root_key.objectid); ret = -EPERM; goto out_drop_sem; } } trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_reset; } ret = btrfs_update_root(trans, root->fs_info->tree_root, &root->root_key, &root->root_item); btrfs_commit_transaction(trans, root); out_reset: if (ret) btrfs_set_root_flags(&root->root_item, root_flags); out_drop_sem: up_write(&root->fs_info->subvol_sem); out_drop_write: mnt_drop_write_file(file); out: return ret; } /* * helper to check if the subvolume references other subvolumes */ static noinline int may_destroy_subvol(struct btrfs_root *root) { struct btrfs_path *path; struct btrfs_dir_item *di; struct btrfs_key key; u64 dir_id; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; /* Make sure this root isn't set as the default subvol */ dir_id = btrfs_super_root_dir(root->fs_info->super_copy); di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path, dir_id, "default", 7, 0); if (di && !IS_ERR(di)) { btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key); if (key.objectid == root->root_key.objectid) { ret = -EPERM; btrfs_err(root->fs_info, "deleting default subvolume " "%llu is not allowed", key.objectid); goto out; } btrfs_release_path(path); } key.objectid = root->root_key.objectid; key.type = BTRFS_ROOT_REF_KEY; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, path, 0, 0); if (ret < 0) goto out; BUG_ON(ret == 0); ret = 0; if (path->slots[0] > 0) { path->slots[0]--; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); if (key.objectid == root->root_key.objectid && key.type == BTRFS_ROOT_REF_KEY) ret = -ENOTEMPTY; } out: btrfs_free_path(path); return ret; } static noinline int key_in_sk(struct btrfs_key *key, struct btrfs_ioctl_search_key *sk) { struct btrfs_key test; int ret; test.objectid = sk->min_objectid; test.type = sk->min_type; test.offset = sk->min_offset; ret = btrfs_comp_cpu_keys(key, &test); if (ret < 0) return 0; test.objectid = sk->max_objectid; test.type = sk->max_type; test.offset = sk->max_offset; ret = btrfs_comp_cpu_keys(key, &test); if (ret > 0) return 0; return 1; } static noinline int copy_to_sk(struct btrfs_root *root, struct btrfs_path *path, struct btrfs_key *key, struct btrfs_ioctl_search_key *sk, size_t *buf_size, char __user *ubuf, unsigned long *sk_offset, int *num_found) { u64 found_transid; struct extent_buffer *leaf; struct btrfs_ioctl_search_header sh; unsigned long item_off; unsigned long item_len; int nritems; int i; int slot; int ret = 0; leaf = path->nodes[0]; slot = path->slots[0]; nritems = btrfs_header_nritems(leaf); if (btrfs_header_generation(leaf) > sk->max_transid) { i = nritems; goto advance_key; } found_transid = btrfs_header_generation(leaf); for (i = slot; i < nritems; i++) { item_off = btrfs_item_ptr_offset(leaf, i); item_len = btrfs_item_size_nr(leaf, i); btrfs_item_key_to_cpu(leaf, key, i); if (!key_in_sk(key, sk)) continue; if (sizeof(sh) + item_len > *buf_size) { if (*num_found) { ret = 1; goto out; } /* * return one empty item back for v1, which does not * handle -EOVERFLOW */ *buf_size = sizeof(sh) + item_len; item_len = 0; ret = -EOVERFLOW; } if (sizeof(sh) + item_len + *sk_offset > *buf_size) { ret = 1; goto out; } sh.objectid = key->objectid; sh.offset = key->offset; sh.type = key->type; sh.len = item_len; sh.transid = found_transid; /* copy search result header */ if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) { ret = -EFAULT; goto out; } *sk_offset += sizeof(sh); if (item_len) { char __user *up = ubuf + *sk_offset; /* copy the item */ if (read_extent_buffer_to_user(leaf, up, item_off, item_len)) { ret = -EFAULT; goto out; } *sk_offset += item_len; } (*num_found)++; if (ret) /* -EOVERFLOW from above */ goto out; if (*num_found >= sk->nr_items) { ret = 1; goto out; } } advance_key: ret = 0; if (key->offset < (u64)-1 && key->offset < sk->max_offset) key->offset++; else if (key->type < (u8)-1 && key->type < sk->max_type) { key->offset = 0; key->type++; } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { key->offset = 0; key->type = 0; key->objectid++; } else ret = 1; out: /* * 0: all items from this leaf copied, continue with next * 1: * more items can be copied, but unused buffer is too small * * all items were found * Either way, it will stops the loop which iterates to the next * leaf * -EOVERFLOW: item was to large for buffer * -EFAULT: could not copy extent buffer back to userspace */ return ret; } static noinline int search_ioctl(struct inode *inode, struct btrfs_ioctl_search_key *sk, size_t *buf_size, char __user *ubuf) { struct btrfs_root *root; struct btrfs_key key; struct btrfs_path *path; struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; int ret; int num_found = 0; unsigned long sk_offset = 0; if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) { *buf_size = sizeof(struct btrfs_ioctl_search_header); return -EOVERFLOW; } path = btrfs_alloc_path(); if (!path) return -ENOMEM; if (sk->tree_id == 0) { /* search the root of the inode that was passed */ root = BTRFS_I(inode)->root; } else { key.objectid = sk->tree_id; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = (u64)-1; root = btrfs_read_fs_root_no_name(info, &key); if (IS_ERR(root)) { printk(KERN_ERR "BTRFS: could not find root %llu\n", sk->tree_id); btrfs_free_path(path); return -ENOENT; } } key.objectid = sk->min_objectid; key.type = sk->min_type; key.offset = sk->min_offset; while (1) { ret = btrfs_search_forward(root, &key, path, sk->min_transid); if (ret != 0) { if (ret > 0) ret = 0; goto err; } ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf, &sk_offset, &num_found); btrfs_release_path(path); if (ret) break; } if (ret > 0) ret = 0; err: sk->nr_items = num_found; btrfs_free_path(path); return ret; } static noinline int btrfs_ioctl_tree_search(struct file *file, void __user *argp) { struct btrfs_ioctl_search_args __user *uargs; struct btrfs_ioctl_search_key sk; struct inode *inode; int ret; size_t buf_size; if (!capable(CAP_SYS_ADMIN)) return -EPERM; uargs = (struct btrfs_ioctl_search_args __user *)argp; if (copy_from_user(&sk, &uargs->key, sizeof(sk))) return -EFAULT; buf_size = sizeof(uargs->buf); inode = file_inode(file); ret = search_ioctl(inode, &sk, &buf_size, uargs->buf); /* * In the origin implementation an overflow is handled by returning a * search header with a len of zero, so reset ret. */ if (ret == -EOVERFLOW) ret = 0; if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk))) ret = -EFAULT; return ret; } static noinline int btrfs_ioctl_tree_search_v2(struct file *file, void __user *argp) { struct btrfs_ioctl_search_args_v2 __user *uarg; struct btrfs_ioctl_search_args_v2 args; struct inode *inode; int ret; size_t buf_size; const size_t buf_limit = 16 * 1024 * 1024; if (!capable(CAP_SYS_ADMIN)) return -EPERM; /* copy search header and buffer size */ uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp; if (copy_from_user(&args, uarg, sizeof(args))) return -EFAULT; buf_size = args.buf_size; if (buf_size < sizeof(struct btrfs_ioctl_search_header)) return -EOVERFLOW; /* limit result size to 16MB */ if (buf_size > buf_limit) buf_size = buf_limit; inode = file_inode(file); ret = search_ioctl(inode, &args.key, &buf_size, (char *)(&uarg->buf[0])); if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key))) ret = -EFAULT; else if (ret == -EOVERFLOW && copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size))) ret = -EFAULT; return ret; } /* * Search INODE_REFs to identify path name of 'dirid' directory * in a 'tree_id' tree. and sets path name to 'name'. */ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, u64 tree_id, u64 dirid, char *name) { struct btrfs_root *root; struct btrfs_key key; char *ptr; int ret = -1; int slot; int len; int total_len = 0; struct btrfs_inode_ref *iref; struct extent_buffer *l; struct btrfs_path *path; if (dirid == BTRFS_FIRST_FREE_OBJECTID) { name[0]='\0'; return 0; } path = btrfs_alloc_path(); if (!path) return -ENOMEM; ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; key.objectid = tree_id; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = (u64)-1; root = btrfs_read_fs_root_no_name(info, &key); if (IS_ERR(root)) { printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id); ret = -ENOENT; goto out; } key.objectid = dirid; key.type = BTRFS_INODE_REF_KEY; key.offset = (u64)-1; while (1) { ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; else if (ret > 0) { ret = btrfs_previous_item(root, path, dirid, BTRFS_INODE_REF_KEY); if (ret < 0) goto out; else if (ret > 0) { ret = -ENOENT; goto out; } } l = path->nodes[0]; slot = path->slots[0]; btrfs_item_key_to_cpu(l, &key, slot); iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); len = btrfs_inode_ref_name_len(l, iref); ptr -= len + 1; total_len += len + 1; if (ptr < name) { ret = -ENAMETOOLONG; goto out; } *(ptr + len) = '/'; read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len); if (key.offset == BTRFS_FIRST_FREE_OBJECTID) break; btrfs_release_path(path); key.objectid = key.offset; key.offset = (u64)-1; dirid = key.objectid; } memmove(name, ptr, total_len); name[total_len] = '\0'; ret = 0; out: btrfs_free_path(path); return ret; } static noinline int btrfs_ioctl_ino_lookup(struct file *file, void __user *argp) { struct btrfs_ioctl_ino_lookup_args *args; struct inode *inode; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; args = memdup_user(argp, sizeof(*args)); if (IS_ERR(args)) return PTR_ERR(args); inode = file_inode(file); if (args->treeid == 0) args->treeid = BTRFS_I(inode)->root->root_key.objectid; ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, args->treeid, args->objectid, args->name); if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) ret = -EFAULT; kfree(args); return ret; } static noinline int btrfs_ioctl_snap_destroy(struct file *file, void __user *arg) { struct dentry *parent = file->f_path.dentry; struct dentry *dentry; struct inode *dir = parent->d_inode; struct inode *inode; struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_root *dest = NULL; struct btrfs_ioctl_vol_args *vol_args; struct btrfs_trans_handle *trans; struct btrfs_block_rsv block_rsv; u64 root_flags; u64 qgroup_reserved; int namelen; int ret; int err = 0; vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) return PTR_ERR(vol_args); vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; namelen = strlen(vol_args->name); if (strchr(vol_args->name, '/') || strncmp(vol_args->name, "..", namelen) == 0) { err = -EINVAL; goto out; } err = mnt_want_write_file(file); if (err) goto out; err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT); if (err == -EINTR) goto out_drop_write; dentry = lookup_one_len(vol_args->name, parent, namelen); if (IS_ERR(dentry)) { err = PTR_ERR(dentry); goto out_unlock_dir; } if (!dentry->d_inode) { err = -ENOENT; goto out_dput; } inode = dentry->d_inode; dest = BTRFS_I(inode)->root; if (!capable(CAP_SYS_ADMIN)) { /* * Regular user. Only allow this with a special mount * option, when the user has write+exec access to the * subvol root, and when rmdir(2) would have been * allowed. * * Note that this is _not_ check that the subvol is * empty or doesn't contain data that we wouldn't * otherwise be able to delete. * * Users who want to delete empty subvols should try * rmdir(2). */ err = -EPERM; if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) goto out_dput; /* * Do not allow deletion if the parent dir is the same * as the dir to be deleted. That means the ioctl * must be called on the dentry referencing the root * of the subvol, not a random directory contained * within it. */ err = -EINVAL; if (root == dest) goto out_dput; err = inode_permission(inode, MAY_WRITE | MAY_EXEC); if (err) goto out_dput; } /* check if subvolume may be deleted by a user */ err = btrfs_may_delete(dir, dentry, 1); if (err) goto out_dput; if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { err = -EINVAL; goto out_dput; } mutex_lock(&inode->i_mutex); /* * Don't allow to delete a subvolume with send in progress. This is * inside the i_mutex so the error handling that has to drop the bit * again is not run concurrently. */ spin_lock(&dest->root_item_lock); root_flags = btrfs_root_flags(&dest->root_item); if (dest->send_in_progress == 0) { btrfs_set_root_flags(&dest->root_item, root_flags | BTRFS_ROOT_SUBVOL_DEAD); spin_unlock(&dest->root_item_lock); } else { spin_unlock(&dest->root_item_lock); btrfs_warn(root->fs_info, "Attempt to delete subvolume %llu during send", dest->root_key.objectid); err = -EPERM; goto out_dput; } d_invalidate(dentry); down_write(&root->fs_info->subvol_sem); err = may_destroy_subvol(dest); if (err) goto out_up_write; btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); /* * One for dir inode, two for dir entries, two for root * ref/backref. */ err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 5, &qgroup_reserved, true); if (err) goto out_up_write; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { err = PTR_ERR(trans); goto out_release; } trans->block_rsv = &block_rsv; trans->bytes_reserved = block_rsv.size; ret = btrfs_unlink_subvol(trans, root, dir, dest->root_key.objectid, dentry->d_name.name, dentry->d_name.len); if (ret) { err = ret; btrfs_abort_transaction(trans, root, ret); goto out_end_trans; } btrfs_record_root_in_trans(trans, dest); memset(&dest->root_item.drop_progress, 0, sizeof(dest->root_item.drop_progress)); dest->root_item.drop_level = 0; btrfs_set_root_refs(&dest->root_item, 0); if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) { ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root, dest->root_key.objectid); if (ret) { btrfs_abort_transaction(trans, root, ret); err = ret; goto out_end_trans; } } ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL, dest->root_key.objectid); if (ret && ret != -ENOENT) { btrfs_abort_transaction(trans, root, ret); err = ret; goto out_end_trans; } if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) { ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, dest->root_item.received_uuid, BTRFS_UUID_KEY_RECEIVED_SUBVOL, dest->root_key.objectid); if (ret && ret != -ENOENT) { btrfs_abort_transaction(trans, root, ret); err = ret; goto out_end_trans; } } out_end_trans: trans->block_rsv = NULL; trans->bytes_reserved = 0; ret = btrfs_end_transaction(trans, root); if (ret && !err) err = ret; inode->i_flags |= S_DEAD; out_release: btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved); out_up_write: up_write(&root->fs_info->subvol_sem); if (err) { spin_lock(&dest->root_item_lock); root_flags = btrfs_root_flags(&dest->root_item); btrfs_set_root_flags(&dest->root_item, root_flags & ~BTRFS_ROOT_SUBVOL_DEAD); spin_unlock(&dest->root_item_lock); } mutex_unlock(&inode->i_mutex); if (!err) { shrink_dcache_sb(root->fs_info->sb); btrfs_invalidate_inodes(dest); d_delete(dentry); ASSERT(dest->send_in_progress == 0); /* the last ref */ if (dest->ino_cache_inode) { iput(dest->ino_cache_inode); dest->ino_cache_inode = NULL; } } out_dput: dput(dentry); out_unlock_dir: mutex_unlock(&dir->i_mutex); out_drop_write: mnt_drop_write_file(file); out: kfree(vol_args); return err; } static int btrfs_ioctl_defrag(struct file *file, void __user *argp) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_ioctl_defrag_range_args *range; int ret; ret = mnt_want_write_file(file); if (ret) return ret; if (btrfs_root_readonly(root)) { ret = -EROFS; goto out; } switch (inode->i_mode & S_IFMT) { case S_IFDIR: if (!capable(CAP_SYS_ADMIN)) { ret = -EPERM; goto out; } ret = btrfs_defrag_root(root); if (ret) goto out; ret = btrfs_defrag_root(root->fs_info->extent_root); break; case S_IFREG: if (!(file->f_mode & FMODE_WRITE)) { ret = -EINVAL; goto out; } range = kzalloc(sizeof(*range), GFP_KERNEL); if (!range) { ret = -ENOMEM; goto out; } if (argp) { if (copy_from_user(range, argp, sizeof(*range))) { ret = -EFAULT; kfree(range); goto out; } /* compression requires us to start the IO */ if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { range->flags |= BTRFS_DEFRAG_RANGE_START_IO; range->extent_thresh = (u32)-1; } } else { /* the rest are all set to zero by kzalloc */ range->len = (u64)-1; } ret = btrfs_defrag_file(file_inode(file), file, range, 0, 0); if (ret > 0) ret = 0; kfree(range); break; default: ret = -EINVAL; } out: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) { struct btrfs_ioctl_vol_args *vol_args; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1)) { return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; } mutex_lock(&root->fs_info->volume_mutex); vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) { ret = PTR_ERR(vol_args); goto out; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; ret = btrfs_init_new_device(root, vol_args->name); if (!ret) btrfs_info(root->fs_info, "disk added %s",vol_args->name); kfree(vol_args); out: mutex_unlock(&root->fs_info->volume_mutex); atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); return ret; } static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_vol_args *vol_args; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; vol_args = memdup_user(arg, sizeof(*vol_args)); if (IS_ERR(vol_args)) { ret = PTR_ERR(vol_args); goto err_drop; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running, 1)) { ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; goto out; } mutex_lock(&root->fs_info->volume_mutex); ret = btrfs_rm_device(root, vol_args->name); mutex_unlock(&root->fs_info->volume_mutex); atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0); if (!ret) btrfs_info(root->fs_info, "disk deleted %s",vol_args->name); out: kfree(vol_args); err_drop: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) { struct btrfs_ioctl_fs_info_args *fi_args; struct btrfs_device *device; struct btrfs_device *next; struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; int ret = 0; fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); if (!fi_args) return -ENOMEM; mutex_lock(&fs_devices->device_list_mutex); fi_args->num_devices = fs_devices->num_devices; memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { if (device->devid > fi_args->max_id) fi_args->max_id = device->devid; } mutex_unlock(&fs_devices->device_list_mutex); fi_args->nodesize = root->fs_info->super_copy->nodesize; fi_args->sectorsize = root->fs_info->super_copy->sectorsize; fi_args->clone_alignment = root->fs_info->super_copy->sectorsize; if (copy_to_user(arg, fi_args, sizeof(*fi_args))) ret = -EFAULT; kfree(fi_args); return ret; } static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) { struct btrfs_ioctl_dev_info_args *di_args; struct btrfs_device *dev; struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; int ret = 0; char *s_uuid = NULL; di_args = memdup_user(arg, sizeof(*di_args)); if (IS_ERR(di_args)) return PTR_ERR(di_args); if (!btrfs_is_empty_uuid(di_args->uuid)) s_uuid = di_args->uuid; mutex_lock(&fs_devices->device_list_mutex); dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL); if (!dev) { ret = -ENODEV; goto out; } di_args->devid = dev->devid; di_args->bytes_used = btrfs_device_get_bytes_used(dev); di_args->total_bytes = btrfs_device_get_total_bytes(dev); memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); if (dev->name) { struct rcu_string *name; rcu_read_lock(); name = rcu_dereference(dev->name); strncpy(di_args->path, name->str, sizeof(di_args->path)); rcu_read_unlock(); di_args->path[sizeof(di_args->path) - 1] = 0; } else { di_args->path[0] = '\0'; } out: mutex_unlock(&fs_devices->device_list_mutex); if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) ret = -EFAULT; kfree(di_args); return ret; } static struct page *extent_same_get_page(struct inode *inode, u64 off) { struct page *page; pgoff_t index; struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree; index = off >> PAGE_CACHE_SHIFT; page = grab_cache_page(inode->i_mapping, index); if (!page) return NULL; if (!PageUptodate(page)) { if (extent_read_full_page_nolock(tree, page, btrfs_get_extent, 0)) return NULL; lock_page(page); if (!PageUptodate(page)) { unlock_page(page); page_cache_release(page); return NULL; } } unlock_page(page); return page; } static inline void lock_extent_range(struct inode *inode, u64 off, u64 len) { /* do any pending delalloc/csum calc on src, one way or another, and lock file content */ while (1) { struct btrfs_ordered_extent *ordered; lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); ordered = btrfs_lookup_first_ordered_extent(inode, off + len - 1); if ((!ordered || ordered->file_offset + ordered->len <= off || ordered->file_offset >= off + len) && !test_range_bit(&BTRFS_I(inode)->io_tree, off, off + len - 1, EXTENT_DELALLOC, 0, NULL)) { if (ordered) btrfs_put_ordered_extent(ordered); break; } unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); if (ordered) btrfs_put_ordered_extent(ordered); btrfs_wait_ordered_range(inode, off, len); } } static void btrfs_double_unlock(struct inode *inode1, u64 loff1, struct inode *inode2, u64 loff2, u64 len) { unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1); unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1); mutex_unlock(&inode1->i_mutex); mutex_unlock(&inode2->i_mutex); } static void btrfs_double_lock(struct inode *inode1, u64 loff1, struct inode *inode2, u64 loff2, u64 len) { if (inode1 < inode2) { swap(inode1, inode2); swap(loff1, loff2); } mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT); lock_extent_range(inode1, loff1, len); if (inode1 != inode2) { mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD); lock_extent_range(inode2, loff2, len); } } static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst, u64 dst_loff, u64 len) { int ret = 0; struct page *src_page, *dst_page; unsigned int cmp_len = PAGE_CACHE_SIZE; void *addr, *dst_addr; while (len) { if (len < PAGE_CACHE_SIZE) cmp_len = len; src_page = extent_same_get_page(src, loff); if (!src_page) return -EINVAL; dst_page = extent_same_get_page(dst, dst_loff); if (!dst_page) { page_cache_release(src_page); return -EINVAL; } addr = kmap_atomic(src_page); dst_addr = kmap_atomic(dst_page); flush_dcache_page(src_page); flush_dcache_page(dst_page); if (memcmp(addr, dst_addr, cmp_len)) ret = BTRFS_SAME_DATA_DIFFERS; kunmap_atomic(addr); kunmap_atomic(dst_addr); page_cache_release(src_page); page_cache_release(dst_page); if (ret) break; loff += cmp_len; dst_loff += cmp_len; len -= cmp_len; } return ret; } static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len) { u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize; if (off + len > inode->i_size || off + len < off) return -EINVAL; /* Check that we are block aligned - btrfs_clone() requires this */ if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs)) return -EINVAL; return 0; } static int btrfs_extent_same(struct inode *src, u64 loff, u64 len, struct inode *dst, u64 dst_loff) { int ret; /* * btrfs_clone() can't handle extents in the same file * yet. Once that works, we can drop this check and replace it * with a check for the same inode, but overlapping extents. */ if (src == dst) return -EINVAL; btrfs_double_lock(src, loff, dst, dst_loff, len); ret = extent_same_check_offsets(src, loff, len); if (ret) goto out_unlock; ret = extent_same_check_offsets(dst, dst_loff, len); if (ret) goto out_unlock; /* don't make the dst file partly checksummed */ if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) { ret = -EINVAL; goto out_unlock; } ret = btrfs_cmp_data(src, loff, dst, dst_loff, len); if (ret == 0) ret = btrfs_clone(src, dst, loff, len, len, dst_loff); out_unlock: btrfs_double_unlock(src, loff, dst, dst_loff, len); return ret; } #define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024) static long btrfs_ioctl_file_extent_same(struct file *file, struct btrfs_ioctl_same_args __user *argp) { struct btrfs_ioctl_same_args *same; struct btrfs_ioctl_same_extent_info *info; struct inode *src = file_inode(file); u64 off; u64 len; int i; int ret; unsigned long size; u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize; bool is_admin = capable(CAP_SYS_ADMIN); u16 count; if (!(file->f_mode & FMODE_READ)) return -EINVAL; ret = mnt_want_write_file(file); if (ret) return ret; if (get_user(count, &argp->dest_count)) { ret = -EFAULT; goto out; } size = offsetof(struct btrfs_ioctl_same_args __user, info[count]); same = memdup_user(argp, size); if (IS_ERR(same)) { ret = PTR_ERR(same); goto out; } off = same->logical_offset; len = same->length; /* * Limit the total length we will dedupe for each operation. * This is intended to bound the total time spent in this * ioctl to something sane. */ if (len > BTRFS_MAX_DEDUPE_LEN) len = BTRFS_MAX_DEDUPE_LEN; if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) { /* * Btrfs does not support blocksize < page_size. As a * result, btrfs_cmp_data() won't correctly handle * this situation without an update. */ ret = -EINVAL; goto out; } ret = -EISDIR; if (S_ISDIR(src->i_mode)) goto out; ret = -EACCES; if (!S_ISREG(src->i_mode)) goto out; /* pre-format output fields to sane values */ for (i = 0; i < count; i++) { same->info[i].bytes_deduped = 0ULL; same->info[i].status = 0; } for (i = 0, info = same->info; i < count; i++, info++) { struct inode *dst; struct fd dst_file = fdget(info->fd); if (!dst_file.file) { info->status = -EBADF; continue; } dst = file_inode(dst_file.file); if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) { info->status = -EINVAL; } else if (file->f_path.mnt != dst_file.file->f_path.mnt) { info->status = -EXDEV; } else if (S_ISDIR(dst->i_mode)) { info->status = -EISDIR; } else if (!S_ISREG(dst->i_mode)) { info->status = -EACCES; } else { info->status = btrfs_extent_same(src, off, len, dst, info->logical_offset); if (info->status == 0) info->bytes_deduped += len; } fdput(dst_file); } ret = copy_to_user(argp, same, size); if (ret) ret = -EFAULT; out: mnt_drop_write_file(file); return ret; } /* Helper to check and see if this root currently has a ref on the given disk * bytenr. If it does then we need to update the quota for this root. This * doesn't do anything if quotas aren't enabled. */ static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 disko) { struct seq_list tree_mod_seq_elem = {}; struct ulist *roots; struct ulist_iterator uiter; struct ulist_node *root_node = NULL; int ret; if (!root->fs_info->quota_enabled) return 1; btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem); ret = btrfs_find_all_roots(trans, root->fs_info, disko, tree_mod_seq_elem.seq, &roots); if (ret < 0) goto out; ret = 0; ULIST_ITER_INIT(&uiter); while ((root_node = ulist_next(roots, &uiter))) { if (root_node->val == root->objectid) { ret = 1; break; } } ulist_free(roots); out: btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem); return ret; } static int clone_finish_inode_update(struct btrfs_trans_handle *trans, struct inode *inode, u64 endoff, const u64 destoff, const u64 olen) { struct btrfs_root *root = BTRFS_I(inode)->root; int ret; inode_inc_iversion(inode); inode->i_mtime = inode->i_ctime = CURRENT_TIME; /* * We round up to the block size at eof when determining which * extents to clone above, but shouldn't round up the file size. */ if (endoff > destoff + olen) endoff = destoff + olen; if (endoff > inode->i_size) btrfs_i_size_write(inode, endoff); ret = btrfs_update_inode(trans, root, inode); if (ret) { btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); goto out; } ret = btrfs_end_transaction(trans, root); out: return ret; } static void clone_update_extent_map(struct inode *inode, const struct btrfs_trans_handle *trans, const struct btrfs_path *path, const u64 hole_offset, const u64 hole_len) { struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; struct extent_map *em; int ret; em = alloc_extent_map(); if (!em) { set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); return; } if (path) { struct btrfs_file_extent_item *fi; fi = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_file_extent_item); btrfs_extent_item_to_extent_map(inode, path, fi, false, em); em->generation = -1; if (btrfs_file_extent_type(path->nodes[0], fi) == BTRFS_FILE_EXTENT_INLINE) set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); } else { em->start = hole_offset; em->len = hole_len; em->ram_bytes = em->len; em->orig_start = hole_offset; em->block_start = EXTENT_MAP_HOLE; em->block_len = 0; em->orig_block_len = 0; em->compress_type = BTRFS_COMPRESS_NONE; em->generation = trans->transid; } while (1) { write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em, 1); write_unlock(&em_tree->lock); if (ret != -EEXIST) { free_extent_map(em); break; } btrfs_drop_extent_cache(inode, em->start, em->start + em->len - 1, 0); } if (ret) set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); } /** * btrfs_clone() - clone a range from inode file to another * * @src: Inode to clone from * @inode: Inode to clone to * @off: Offset within source to start clone from * @olen: Original length, passed by user, of range to clone * @olen_aligned: Block-aligned value of olen, extent_same uses * identical values here * @destoff: Offset within @inode to start clone */ static int btrfs_clone(struct inode *src, struct inode *inode, const u64 off, const u64 olen, const u64 olen_aligned, const u64 destoff) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_path *path = NULL; struct extent_buffer *leaf; struct btrfs_trans_handle *trans; char *buf = NULL; struct btrfs_key key; u32 nritems; int slot; int ret; int no_quota; const u64 len = olen_aligned; u64 last_disko = 0; u64 last_dest_end = destoff; ret = -ENOMEM; buf = vmalloc(root->nodesize); if (!buf) return ret; path = btrfs_alloc_path(); if (!path) { vfree(buf); return ret; } path->reada = 2; /* clone data */ key.objectid = btrfs_ino(src); key.type = BTRFS_EXTENT_DATA_KEY; key.offset = off; while (1) { /* * note the key will change type as we walk through the * tree. */ path->leave_spinning = 1; ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path, 0, 0); if (ret < 0) goto out; /* * First search, if no extent item that starts at offset off was * found but the previous item is an extent item, it's possible * it might overlap our target range, therefore process it. */ if (key.offset == off && ret > 0 && path->slots[0] > 0) { btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0] - 1); if (key.type == BTRFS_EXTENT_DATA_KEY) path->slots[0]--; } nritems = btrfs_header_nritems(path->nodes[0]); process_slot: no_quota = 1; if (path->slots[0] >= nritems) { ret = btrfs_next_leaf(BTRFS_I(src)->root, path); if (ret < 0) goto out; if (ret > 0) break; nritems = btrfs_header_nritems(path->nodes[0]); } leaf = path->nodes[0]; slot = path->slots[0]; btrfs_item_key_to_cpu(leaf, &key, slot); if (key.type > BTRFS_EXTENT_DATA_KEY || key.objectid != btrfs_ino(src)) break; if (key.type == BTRFS_EXTENT_DATA_KEY) { struct btrfs_file_extent_item *extent; int type; u32 size; struct btrfs_key new_key; u64 disko = 0, diskl = 0; u64 datao = 0, datal = 0; u8 comp; u64 drop_start; extent = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); comp = btrfs_file_extent_compression(leaf, extent); type = btrfs_file_extent_type(leaf, extent); if (type == BTRFS_FILE_EXTENT_REG || type == BTRFS_FILE_EXTENT_PREALLOC) { disko = btrfs_file_extent_disk_bytenr(leaf, extent); diskl = btrfs_file_extent_disk_num_bytes(leaf, extent); datao = btrfs_file_extent_offset(leaf, extent); datal = btrfs_file_extent_num_bytes(leaf, extent); } else if (type == BTRFS_FILE_EXTENT_INLINE) { /* take upper bound, may be compressed */ datal = btrfs_file_extent_ram_bytes(leaf, extent); } /* * The first search might have left us at an extent * item that ends before our target range's start, can * happen if we have holes and NO_HOLES feature enabled. */ if (key.offset + datal <= off) { path->slots[0]++; goto process_slot; } else if (key.offset >= off + len) { break; } size = btrfs_item_size_nr(leaf, slot); read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf, slot), size); btrfs_release_path(path); path->leave_spinning = 0; memcpy(&new_key, &key, sizeof(new_key)); new_key.objectid = btrfs_ino(inode); if (off <= key.offset) new_key.offset = key.offset + destoff - off; else new_key.offset = destoff; /* * Deal with a hole that doesn't have an extent item * that represents it (NO_HOLES feature enabled). * This hole is either in the middle of the cloning * range or at the beginning (fully overlaps it or * partially overlaps it). */ if (new_key.offset != last_dest_end) drop_start = last_dest_end; else drop_start = new_key.offset; /* * 1 - adjusting old extent (we may have to split it) * 1 - add new extent * 1 - inode update */ trans = btrfs_start_transaction(root, 3); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } if (type == BTRFS_FILE_EXTENT_REG || type == BTRFS_FILE_EXTENT_PREALLOC) { /* * a | --- range to clone ---| b * | ------------- extent ------------- | */ /* subtract range b */ if (key.offset + datal > off + len) datal = off + len - key.offset; /* subtract range a */ if (off > key.offset) { datao += off - key.offset; datal -= off - key.offset; } ret = btrfs_drop_extents(trans, root, inode, drop_start, new_key.offset + datal, 1); if (ret) { if (ret != -EOPNOTSUPP) btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); goto out; } ret = btrfs_insert_empty_item(trans, root, path, &new_key, size); if (ret) { btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); goto out; } leaf = path->nodes[0]; slot = path->slots[0]; write_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf, slot), size); extent = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); /* disko == 0 means it's a hole */ if (!disko) datao = 0; btrfs_set_file_extent_offset(leaf, extent, datao); btrfs_set_file_extent_num_bytes(leaf, extent, datal); /* * We need to look up the roots that point at * this bytenr and see if the new root does. If * it does not we need to make sure we update * quotas appropriately. */ if (disko && root != BTRFS_I(src)->root && disko != last_disko) { no_quota = check_ref(trans, root, disko); if (no_quota < 0) { btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); ret = no_quota; goto out; } } if (disko) { inode_add_bytes(inode, datal); ret = btrfs_inc_extent_ref(trans, root, disko, diskl, 0, root->root_key.objectid, btrfs_ino(inode), new_key.offset - datao, no_quota); if (ret) { btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); goto out; } } } else if (type == BTRFS_FILE_EXTENT_INLINE) { u64 skip = 0; u64 trim = 0; u64 aligned_end = 0; if (off > key.offset) { skip = off - key.offset; new_key.offset += skip; } if (key.offset + datal > off + len) trim = key.offset + datal - (off + len); if (comp && (skip || trim)) { ret = -EINVAL; btrfs_end_transaction(trans, root); goto out; } size -= skip + trim; datal -= skip + trim; aligned_end = ALIGN(new_key.offset + datal, root->sectorsize); ret = btrfs_drop_extents(trans, root, inode, drop_start, aligned_end, 1); if (ret) { if (ret != -EOPNOTSUPP) btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); goto out; } ret = btrfs_insert_empty_item(trans, root, path, &new_key, size); if (ret) { btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); goto out; } if (skip) { u32 start = btrfs_file_extent_calc_inline_size(0); memmove(buf+start, buf+start+skip, datal); } leaf = path->nodes[0]; slot = path->slots[0]; write_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf, slot), size); inode_add_bytes(inode, datal); } /* If we have an implicit hole (NO_HOLES feature). */ if (drop_start < new_key.offset) clone_update_extent_map(inode, trans, NULL, drop_start, new_key.offset - drop_start); clone_update_extent_map(inode, trans, path, 0, 0); btrfs_mark_buffer_dirty(leaf); btrfs_release_path(path); last_dest_end = ALIGN(new_key.offset + datal, root->sectorsize); ret = clone_finish_inode_update(trans, inode, last_dest_end, destoff, olen); if (ret) goto out; if (new_key.offset + datal >= destoff + len) break; } btrfs_release_path(path); key.offset++; } ret = 0; if (last_dest_end < destoff + len) { /* * We have an implicit hole (NO_HOLES feature is enabled) that * fully or partially overlaps our cloning range at its end. */ btrfs_release_path(path); /* * 1 - remove extent(s) * 1 - inode update */ trans = btrfs_start_transaction(root, 2); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } ret = btrfs_drop_extents(trans, root, inode, last_dest_end, destoff + len, 1); if (ret) { if (ret != -EOPNOTSUPP) btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); goto out; } clone_update_extent_map(inode, trans, NULL, last_dest_end, destoff + len - last_dest_end); ret = clone_finish_inode_update(trans, inode, destoff + len, destoff, olen); } out: btrfs_free_path(path); vfree(buf); return ret; } static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off, u64 olen, u64 destoff) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct fd src_file; struct inode *src; int ret; u64 len = olen; u64 bs = root->fs_info->sb->s_blocksize; int same_inode = 0; /* * TODO: * - split compressed inline extents. annoying: we need to * decompress into destination's address_space (the file offset * may change, so source mapping won't do), then recompress (or * otherwise reinsert) a subrange. * * - split destination inode's inline extents. The inline extents can * be either compressed or non-compressed. */ /* the destination must be opened for writing */ if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) return -EINVAL; if (btrfs_root_readonly(root)) return -EROFS; ret = mnt_want_write_file(file); if (ret) return ret; src_file = fdget(srcfd); if (!src_file.file) { ret = -EBADF; goto out_drop_write; } ret = -EXDEV; if (src_file.file->f_path.mnt != file->f_path.mnt) goto out_fput; src = file_inode(src_file.file); ret = -EINVAL; if (src == inode) same_inode = 1; /* the src must be open for reading */ if (!(src_file.file->f_mode & FMODE_READ)) goto out_fput; /* don't make the dst file partly checksummed */ if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) goto out_fput; ret = -EISDIR; if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) goto out_fput; ret = -EXDEV; if (src->i_sb != inode->i_sb) goto out_fput; if (!same_inode) { if (inode < src) { mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); } else { mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); } } else { mutex_lock(&src->i_mutex); } /* determine range to clone */ ret = -EINVAL; if (off + len > src->i_size || off + len < off) goto out_unlock; if (len == 0) olen = len = src->i_size - off; /* if we extend to eof, continue to block boundary */ if (off + len == src->i_size) len = ALIGN(src->i_size, bs) - off; /* verify the end result is block aligned */ if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || !IS_ALIGNED(destoff, bs)) goto out_unlock; /* verify if ranges are overlapped within the same file */ if (same_inode) { if (destoff + len > off && destoff < off + len) goto out_unlock; } if (destoff > inode->i_size) { ret = btrfs_cont_expand(inode, inode->i_size, destoff); if (ret) goto out_unlock; } /* * Lock the target range too. Right after we replace the file extent * items in the fs tree (which now point to the cloned data), we might * have a worker replace them with extent items relative to a write * operation that was issued before this clone operation (i.e. confront * with inode.c:btrfs_finish_ordered_io). */ if (same_inode) { u64 lock_start = min_t(u64, off, destoff); u64 lock_len = max_t(u64, off, destoff) + len - lock_start; lock_extent_range(src, lock_start, lock_len); } else { lock_extent_range(src, off, len); lock_extent_range(inode, destoff, len); } ret = btrfs_clone(src, inode, off, olen, len, destoff); if (same_inode) { u64 lock_start = min_t(u64, off, destoff); u64 lock_end = max_t(u64, off, destoff) + len - 1; unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end); } else { unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); unlock_extent(&BTRFS_I(inode)->io_tree, destoff, destoff + len - 1); } /* * Truncate page cache pages so that future reads will see the cloned * data immediately and not the previous data. */ truncate_inode_pages_range(&inode->i_data, destoff, PAGE_CACHE_ALIGN(destoff + len) - 1); out_unlock: if (!same_inode) { if (inode < src) { mutex_unlock(&src->i_mutex); mutex_unlock(&inode->i_mutex); } else { mutex_unlock(&inode->i_mutex); mutex_unlock(&src->i_mutex); } } else { mutex_unlock(&src->i_mutex); } out_fput: fdput(src_file); out_drop_write: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) { struct btrfs_ioctl_clone_range_args args; if (copy_from_user(&args, argp, sizeof(args))) return -EFAULT; return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, args.src_length, args.dest_offset); } /* * there are many ways the trans_start and trans_end ioctls can lead * to deadlocks. They should only be used by applications that * basically own the machine, and have a very in depth understanding * of all the possible deadlocks and enospc problems. */ static long btrfs_ioctl_trans_start(struct file *file) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; int ret; ret = -EPERM; if (!capable(CAP_SYS_ADMIN)) goto out; ret = -EINPROGRESS; if (file->private_data) goto out; ret = -EROFS; if (btrfs_root_readonly(root)) goto out; ret = mnt_want_write_file(file); if (ret) goto out; atomic_inc(&root->fs_info->open_ioctl_trans); ret = -ENOMEM; trans = btrfs_start_ioctl_transaction(root); if (IS_ERR(trans)) goto out_drop; file->private_data = trans; return 0; out_drop: atomic_dec(&root->fs_info->open_ioctl_trans); mnt_drop_write_file(file); out: return ret; } static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_root *new_root; struct btrfs_dir_item *di; struct btrfs_trans_handle *trans; struct btrfs_path *path; struct btrfs_key location; struct btrfs_disk_key disk_key; u64 objectid = 0; u64 dir_id; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; if (copy_from_user(&objectid, argp, sizeof(objectid))) { ret = -EFAULT; goto out; } if (!objectid) objectid = BTRFS_FS_TREE_OBJECTID; location.objectid = objectid; location.type = BTRFS_ROOT_ITEM_KEY; location.offset = (u64)-1; new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); if (IS_ERR(new_root)) { ret = PTR_ERR(new_root); goto out; } path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } path->leave_spinning = 1; trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { btrfs_free_path(path); ret = PTR_ERR(trans); goto out; } dir_id = btrfs_super_root_dir(root->fs_info->super_copy); di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, dir_id, "default", 7, 1); if (IS_ERR_OR_NULL(di)) { btrfs_free_path(path); btrfs_end_transaction(trans, root); btrfs_err(new_root->fs_info, "Umm, you don't have the default dir" "item, this isn't going to work"); ret = -ENOENT; goto out; } btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); btrfs_mark_buffer_dirty(path->nodes[0]); btrfs_free_path(path); btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL); btrfs_end_transaction(trans, root); out: mnt_drop_write_file(file); return ret; } void btrfs_get_block_group_info(struct list_head *groups_list, struct btrfs_ioctl_space_info *space) { struct btrfs_block_group_cache *block_group; space->total_bytes = 0; space->used_bytes = 0; space->flags = 0; list_for_each_entry(block_group, groups_list, list) { space->flags = block_group->flags; space->total_bytes += block_group->key.offset; space->used_bytes += btrfs_block_group_used(&block_group->item); } } static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) { struct btrfs_ioctl_space_args space_args; struct btrfs_ioctl_space_info space; struct btrfs_ioctl_space_info *dest; struct btrfs_ioctl_space_info *dest_orig; struct btrfs_ioctl_space_info __user *user_dest; struct btrfs_space_info *info; u64 types[] = {BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_SYSTEM, BTRFS_BLOCK_GROUP_METADATA, BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; int num_types = 4; int alloc_size; int ret = 0; u64 slot_count = 0; int i, c; if (copy_from_user(&space_args, (struct btrfs_ioctl_space_args __user *)arg, sizeof(space_args))) return -EFAULT; for (i = 0; i < num_types; i++) { struct btrfs_space_info *tmp; info = NULL; rcu_read_lock(); list_for_each_entry_rcu(tmp, &root->fs_info->space_info, list) { if (tmp->flags == types[i]) { info = tmp; break; } } rcu_read_unlock(); if (!info) continue; down_read(&info->groups_sem); for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { if (!list_empty(&info->block_groups[c])) slot_count++; } up_read(&info->groups_sem); } /* * Global block reserve, exported as a space_info */ slot_count++; /* space_slots == 0 means they are asking for a count */ if (space_args.space_slots == 0) { space_args.total_spaces = slot_count; goto out; } slot_count = min_t(u64, space_args.space_slots, slot_count); alloc_size = sizeof(*dest) * slot_count; /* we generally have at most 6 or so space infos, one for each raid * level. So, a whole page should be more than enough for everyone */ if (alloc_size > PAGE_CACHE_SIZE) return -ENOMEM; space_args.total_spaces = 0; dest = kmalloc(alloc_size, GFP_NOFS); if (!dest) return -ENOMEM; dest_orig = dest; /* now we have a buffer to copy into */ for (i = 0; i < num_types; i++) { struct btrfs_space_info *tmp; if (!slot_count) break; info = NULL; rcu_read_lock(); list_for_each_entry_rcu(tmp, &root->fs_info->space_info, list) { if (tmp->flags == types[i]) { info = tmp; break; } } rcu_read_unlock(); if (!info) continue; down_read(&info->groups_sem); for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { if (!list_empty(&info->block_groups[c])) { btrfs_get_block_group_info( &info->block_groups[c], &space); memcpy(dest, &space, sizeof(space)); dest++; space_args.total_spaces++; slot_count--; } if (!slot_count) break; } up_read(&info->groups_sem); } /* * Add global block reserve */ if (slot_count) { struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv; spin_lock(&block_rsv->lock); space.total_bytes = block_rsv->size; space.used_bytes = block_rsv->size - block_rsv->reserved; spin_unlock(&block_rsv->lock); space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV; memcpy(dest, &space, sizeof(space)); space_args.total_spaces++; } user_dest = (struct btrfs_ioctl_space_info __user *) (arg + sizeof(struct btrfs_ioctl_space_args)); if (copy_to_user(user_dest, dest_orig, alloc_size)) ret = -EFAULT; kfree(dest_orig); out: if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) ret = -EFAULT; return ret; } /* * there are many ways the trans_start and trans_end ioctls can lead * to deadlocks. They should only be used by applications that * basically own the machine, and have a very in depth understanding * of all the possible deadlocks and enospc problems. */ long btrfs_ioctl_trans_end(struct file *file) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; trans = file->private_data; if (!trans) return -EINVAL; file->private_data = NULL; btrfs_end_transaction(trans, root); atomic_dec(&root->fs_info->open_ioctl_trans); mnt_drop_write_file(file); return 0; } static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root, void __user *argp) { struct btrfs_trans_handle *trans; u64 transid; int ret; trans = btrfs_attach_transaction_barrier(root); if (IS_ERR(trans)) { if (PTR_ERR(trans) != -ENOENT) return PTR_ERR(trans); /* No running transaction, don't bother */ transid = root->fs_info->last_trans_committed; goto out; } transid = trans->transid; ret = btrfs_commit_transaction_async(trans, root, 0); if (ret) { btrfs_end_transaction(trans, root); return ret; } out: if (argp) if (copy_to_user(argp, &transid, sizeof(transid))) return -EFAULT; return 0; } static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root, void __user *argp) { u64 transid; if (argp) { if (copy_from_user(&transid, argp, sizeof(transid))) return -EFAULT; } else { transid = 0; /* current trans */ } return btrfs_wait_for_commit(root, transid); } static long btrfs_ioctl_scrub(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_scrub_args *sa; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) return PTR_ERR(sa); if (!(sa->flags & BTRFS_SCRUB_READONLY)) { ret = mnt_want_write_file(file); if (ret) goto out; } ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end, &sa->progress, sa->flags & BTRFS_SCRUB_READONLY, 0); if (copy_to_user(arg, sa, sizeof(*sa))) ret = -EFAULT; if (!(sa->flags & BTRFS_SCRUB_READONLY)) mnt_drop_write_file(file); out: kfree(sa); return ret; } static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg) { if (!capable(CAP_SYS_ADMIN)) return -EPERM; return btrfs_scrub_cancel(root->fs_info); } static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, void __user *arg) { struct btrfs_ioctl_scrub_args *sa; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) return PTR_ERR(sa); ret = btrfs_scrub_progress(root, sa->devid, &sa->progress); if (copy_to_user(arg, sa, sizeof(*sa))) ret = -EFAULT; kfree(sa); return ret; } static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root, void __user *arg) { struct btrfs_ioctl_get_dev_stats *sa; int ret; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) return PTR_ERR(sa); if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) { kfree(sa); return -EPERM; } ret = btrfs_get_dev_stats(root, sa); if (copy_to_user(arg, sa, sizeof(*sa))) ret = -EFAULT; kfree(sa); return ret; } static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg) { struct btrfs_ioctl_dev_replace_args *p; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; p = memdup_user(arg, sizeof(*p)); if (IS_ERR(p)) return PTR_ERR(p); switch (p->cmd) { case BTRFS_IOCTL_DEV_REPLACE_CMD_START: if (root->fs_info->sb->s_flags & MS_RDONLY) { ret = -EROFS; goto out; } if (atomic_xchg( &root->fs_info->mutually_exclusive_operation_running, 1)) { ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; } else { ret = btrfs_dev_replace_start(root, p); atomic_set( &root->fs_info->mutually_exclusive_operation_running, 0); } break; case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS: btrfs_dev_replace_status(root->fs_info, p); ret = 0; break; case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL: ret = btrfs_dev_replace_cancel(root->fs_info, p); break; default: ret = -EINVAL; break; } if (copy_to_user(arg, p, sizeof(*p))) ret = -EFAULT; out: kfree(p); return ret; } static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) { int ret = 0; int i; u64 rel_ptr; int size; struct btrfs_ioctl_ino_path_args *ipa = NULL; struct inode_fs_paths *ipath = NULL; struct btrfs_path *path; if (!capable(CAP_DAC_READ_SEARCH)) return -EPERM; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } ipa = memdup_user(arg, sizeof(*ipa)); if (IS_ERR(ipa)) { ret = PTR_ERR(ipa); ipa = NULL; goto out; } size = min_t(u32, ipa->size, 4096); ipath = init_ipath(size, root, path); if (IS_ERR(ipath)) { ret = PTR_ERR(ipath); ipath = NULL; goto out; } ret = paths_from_inode(ipa->inum, ipath); if (ret < 0) goto out; for (i = 0; i < ipath->fspath->elem_cnt; ++i) { rel_ptr = ipath->fspath->val[i] - (u64)(unsigned long)ipath->fspath->val; ipath->fspath->val[i] = rel_ptr; } ret = copy_to_user((void *)(unsigned long)ipa->fspath, (void *)(unsigned long)ipath->fspath, size); if (ret) { ret = -EFAULT; goto out; } out: btrfs_free_path(path); free_ipath(ipath); kfree(ipa); return ret; } static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) { struct btrfs_data_container *inodes = ctx; const size_t c = 3 * sizeof(u64); if (inodes->bytes_left >= c) { inodes->bytes_left -= c; inodes->val[inodes->elem_cnt] = inum; inodes->val[inodes->elem_cnt + 1] = offset; inodes->val[inodes->elem_cnt + 2] = root; inodes->elem_cnt += 3; } else { inodes->bytes_missing += c - inodes->bytes_left; inodes->bytes_left = 0; inodes->elem_missed += 3; } return 0; } static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, void __user *arg) { int ret = 0; int size; struct btrfs_ioctl_logical_ino_args *loi; struct btrfs_data_container *inodes = NULL; struct btrfs_path *path = NULL; if (!capable(CAP_SYS_ADMIN)) return -EPERM; loi = memdup_user(arg, sizeof(*loi)); if (IS_ERR(loi)) { ret = PTR_ERR(loi); loi = NULL; goto out; } path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } size = min_t(u32, loi->size, 64 * 1024); inodes = init_data_container(size); if (IS_ERR(inodes)) { ret = PTR_ERR(inodes); inodes = NULL; goto out; } ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path, build_ino_list, inodes); if (ret == -EINVAL) ret = -ENOENT; if (ret < 0) goto out; ret = copy_to_user((void *)(unsigned long)loi->inodes, (void *)(unsigned long)inodes, size); if (ret) ret = -EFAULT; out: btrfs_free_path(path); vfree(inodes); kfree(loi); return ret; } void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, struct btrfs_ioctl_balance_args *bargs) { struct btrfs_balance_control *bctl = fs_info->balance_ctl; bargs->flags = bctl->flags; if (atomic_read(&fs_info->balance_running)) bargs->state |= BTRFS_BALANCE_STATE_RUNNING; if (atomic_read(&fs_info->balance_pause_req)) bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; if (atomic_read(&fs_info->balance_cancel_req)) bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); if (lock) { spin_lock(&fs_info->balance_lock); memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); spin_unlock(&fs_info->balance_lock); } else { memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); } } static long btrfs_ioctl_balance(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_ioctl_balance_args *bargs; struct btrfs_balance_control *bctl; bool need_unlock; /* for mut. excl. ops lock */ int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; again: if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) { mutex_lock(&fs_info->volume_mutex); mutex_lock(&fs_info->balance_mutex); need_unlock = true; goto locked; } /* * mut. excl. ops lock is locked. Three possibilites: * (1) some other op is running * (2) balance is running * (3) balance is paused -- special case (think resume) */ mutex_lock(&fs_info->balance_mutex); if (fs_info->balance_ctl) { /* this is either (2) or (3) */ if (!atomic_read(&fs_info->balance_running)) { mutex_unlock(&fs_info->balance_mutex); if (!mutex_trylock(&fs_info->volume_mutex)) goto again; mutex_lock(&fs_info->balance_mutex); if (fs_info->balance_ctl && !atomic_read(&fs_info->balance_running)) { /* this is (3) */ need_unlock = false; goto locked; } mutex_unlock(&fs_info->balance_mutex); mutex_unlock(&fs_info->volume_mutex); goto again; } else { /* this is (2) */ mutex_unlock(&fs_info->balance_mutex); ret = -EINPROGRESS; goto out; } } else { /* this is (1) */ mutex_unlock(&fs_info->balance_mutex); ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; goto out; } locked: BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running)); if (arg) { bargs = memdup_user(arg, sizeof(*bargs)); if (IS_ERR(bargs)) { ret = PTR_ERR(bargs); goto out_unlock; } if (bargs->flags & BTRFS_BALANCE_RESUME) { if (!fs_info->balance_ctl) { ret = -ENOTCONN; goto out_bargs; } bctl = fs_info->balance_ctl; spin_lock(&fs_info->balance_lock); bctl->flags |= BTRFS_BALANCE_RESUME; spin_unlock(&fs_info->balance_lock); goto do_balance; } } else { bargs = NULL; } if (fs_info->balance_ctl) { ret = -EINPROGRESS; goto out_bargs; } bctl = kzalloc(sizeof(*bctl), GFP_NOFS); if (!bctl) { ret = -ENOMEM; goto out_bargs; } bctl->fs_info = fs_info; if (arg) { memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); bctl->flags = bargs->flags; } else { /* balance everything - no filters */ bctl->flags |= BTRFS_BALANCE_TYPE_MASK; } do_balance: /* * Ownership of bctl and mutually_exclusive_operation_running * goes to to btrfs_balance. bctl is freed in __cancel_balance, * or, if restriper was paused all the way until unmount, in * free_fs_info. mutually_exclusive_operation_running is * cleared in __cancel_balance. */ need_unlock = false; ret = btrfs_balance(bctl, bargs); if (arg) { if (copy_to_user(arg, bargs, sizeof(*bargs))) ret = -EFAULT; } out_bargs: kfree(bargs); out_unlock: mutex_unlock(&fs_info->balance_mutex); mutex_unlock(&fs_info->volume_mutex); if (need_unlock) atomic_set(&fs_info->mutually_exclusive_operation_running, 0); out: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd) { if (!capable(CAP_SYS_ADMIN)) return -EPERM; switch (cmd) { case BTRFS_BALANCE_CTL_PAUSE: return btrfs_pause_balance(root->fs_info); case BTRFS_BALANCE_CTL_CANCEL: return btrfs_cancel_balance(root->fs_info); } return -EINVAL; } static long btrfs_ioctl_balance_progress(struct btrfs_root *root, void __user *arg) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_ioctl_balance_args *bargs; int ret = 0; if (!capable(CAP_SYS_ADMIN)) return -EPERM; mutex_lock(&fs_info->balance_mutex); if (!fs_info->balance_ctl) { ret = -ENOTCONN; goto out; } bargs = kzalloc(sizeof(*bargs), GFP_NOFS); if (!bargs) { ret = -ENOMEM; goto out; } update_ioctl_balance_args(fs_info, 1, bargs); if (copy_to_user(arg, bargs, sizeof(*bargs))) ret = -EFAULT; kfree(bargs); out: mutex_unlock(&fs_info->balance_mutex); return ret; } static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_quota_ctl_args *sa; struct btrfs_trans_handle *trans = NULL; int ret; int err; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) { ret = PTR_ERR(sa); goto drop_write; } down_write(&root->fs_info->subvol_sem); trans = btrfs_start_transaction(root->fs_info->tree_root, 2); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } switch (sa->cmd) { case BTRFS_QUOTA_CTL_ENABLE: ret = btrfs_quota_enable(trans, root->fs_info); break; case BTRFS_QUOTA_CTL_DISABLE: ret = btrfs_quota_disable(trans, root->fs_info); break; default: ret = -EINVAL; break; } err = btrfs_commit_transaction(trans, root->fs_info->tree_root); if (err && !ret) ret = err; out: kfree(sa); up_write(&root->fs_info->subvol_sem); drop_write: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_qgroup_assign_args *sa; struct btrfs_trans_handle *trans; int ret; int err; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) { ret = PTR_ERR(sa); goto drop_write; } trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } /* FIXME: check if the IDs really exist */ if (sa->assign) { ret = btrfs_add_qgroup_relation(trans, root->fs_info, sa->src, sa->dst); } else { ret = btrfs_del_qgroup_relation(trans, root->fs_info, sa->src, sa->dst); } err = btrfs_end_transaction(trans, root); if (err && !ret) ret = err; out: kfree(sa); drop_write: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_qgroup_create_args *sa; struct btrfs_trans_handle *trans; int ret; int err; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) { ret = PTR_ERR(sa); goto drop_write; } if (!sa->qgroupid) { ret = -EINVAL; goto out; } trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } /* FIXME: check if the IDs really exist */ if (sa->create) { ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid, NULL); } else { ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid); } err = btrfs_end_transaction(trans, root); if (err && !ret) ret = err; out: kfree(sa); drop_write: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_qgroup_limit_args *sa; struct btrfs_trans_handle *trans; int ret; int err; u64 qgroupid; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) { ret = PTR_ERR(sa); goto drop_write; } trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } qgroupid = sa->qgroupid; if (!qgroupid) { /* take the current subvol as qgroup */ qgroupid = root->root_key.objectid; } /* FIXME: check if the IDs really exist */ ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim); err = btrfs_end_transaction(trans, root); if (err && !ret) ret = err; out: kfree(sa); drop_write: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_quota_rescan_args *qsa; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write_file(file); if (ret) return ret; qsa = memdup_user(arg, sizeof(*qsa)); if (IS_ERR(qsa)) { ret = PTR_ERR(qsa); goto drop_write; } if (qsa->flags) { ret = -EINVAL; goto out; } ret = btrfs_qgroup_rescan(root->fs_info); out: kfree(qsa); drop_write: mnt_drop_write_file(file); return ret; } static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_ioctl_quota_rescan_args *qsa; int ret = 0; if (!capable(CAP_SYS_ADMIN)) return -EPERM; qsa = kzalloc(sizeof(*qsa), GFP_NOFS); if (!qsa) return -ENOMEM; if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { qsa->flags = 1; qsa->progress = root->fs_info->qgroup_rescan_progress.objectid; } if (copy_to_user(arg, qsa, sizeof(*qsa))) ret = -EFAULT; kfree(qsa); return ret; } static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; if (!capable(CAP_SYS_ADMIN)) return -EPERM; return btrfs_qgroup_wait_for_completion(root->fs_info); } static long _btrfs_ioctl_set_received_subvol(struct file *file, struct btrfs_ioctl_received_subvol_args *sa) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_root_item *root_item = &root->root_item; struct btrfs_trans_handle *trans; struct timespec ct = CURRENT_TIME; int ret = 0; int received_uuid_changed; if (!inode_owner_or_capable(inode)) return -EPERM; ret = mnt_want_write_file(file); if (ret < 0) return ret; down_write(&root->fs_info->subvol_sem); if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { ret = -EINVAL; goto out; } if (btrfs_root_readonly(root)) { ret = -EROFS; goto out; } /* * 1 - root item * 2 - uuid items (received uuid + subvol uuid) */ trans = btrfs_start_transaction(root, 3); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; goto out; } sa->rtransid = trans->transid; sa->rtime.sec = ct.tv_sec; sa->rtime.nsec = ct.tv_nsec; received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); if (received_uuid_changed && !btrfs_is_empty_uuid(root_item->received_uuid)) btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root, root_item->received_uuid, BTRFS_UUID_KEY_RECEIVED_SUBVOL, root->root_key.objectid); memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); btrfs_set_root_stransid(root_item, sa->stransid); btrfs_set_root_rtransid(root_item, sa->rtransid); btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec); btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec); btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec); btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec); ret = btrfs_update_root(trans, root->fs_info->tree_root, &root->root_key, &root->root_item); if (ret < 0) { btrfs_end_transaction(trans, root); goto out; } if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) { ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root, sa->uuid, BTRFS_UUID_KEY_RECEIVED_SUBVOL, root->root_key.objectid); if (ret < 0 && ret != -EEXIST) { btrfs_abort_transaction(trans, root, ret); goto out; } } ret = btrfs_commit_transaction(trans, root); if (ret < 0) { btrfs_abort_transaction(trans, root, ret); goto out; } out: up_write(&root->fs_info->subvol_sem); mnt_drop_write_file(file); return ret; } #ifdef CONFIG_64BIT static long btrfs_ioctl_set_received_subvol_32(struct file *file, void __user *arg) { struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL; struct btrfs_ioctl_received_subvol_args *args64 = NULL; int ret = 0; args32 = memdup_user(arg, sizeof(*args32)); if (IS_ERR(args32)) { ret = PTR_ERR(args32); args32 = NULL; goto out; } args64 = kmalloc(sizeof(*args64), GFP_NOFS); if (!args64) { ret = -ENOMEM; goto out; } memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE); args64->stransid = args32->stransid; args64->rtransid = args32->rtransid; args64->stime.sec = args32->stime.sec; args64->stime.nsec = args32->stime.nsec; args64->rtime.sec = args32->rtime.sec; args64->rtime.nsec = args32->rtime.nsec; args64->flags = args32->flags; ret = _btrfs_ioctl_set_received_subvol(file, args64); if (ret) goto out; memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE); args32->stransid = args64->stransid; args32->rtransid = args64->rtransid; args32->stime.sec = args64->stime.sec; args32->stime.nsec = args64->stime.nsec; args32->rtime.sec = args64->rtime.sec; args32->rtime.nsec = args64->rtime.nsec; args32->flags = args64->flags; ret = copy_to_user(arg, args32, sizeof(*args32)); if (ret) ret = -EFAULT; out: kfree(args32); kfree(args64); return ret; } #endif static long btrfs_ioctl_set_received_subvol(struct file *file, void __user *arg) { struct btrfs_ioctl_received_subvol_args *sa = NULL; int ret = 0; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) { ret = PTR_ERR(sa); sa = NULL; goto out; } ret = _btrfs_ioctl_set_received_subvol(file, sa); if (ret) goto out; ret = copy_to_user(arg, sa, sizeof(*sa)); if (ret) ret = -EFAULT; out: kfree(sa); return ret; } static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; size_t len; int ret; char label[BTRFS_LABEL_SIZE]; spin_lock(&root->fs_info->super_lock); memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE); spin_unlock(&root->fs_info->super_lock); len = strnlen(label, BTRFS_LABEL_SIZE); if (len == BTRFS_LABEL_SIZE) { btrfs_warn(root->fs_info, "label is too long, return the first %zu bytes", --len); } ret = copy_to_user(arg, label, len); return ret ? -EFAULT : 0; } static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_super_block *super_block = root->fs_info->super_copy; struct btrfs_trans_handle *trans; char label[BTRFS_LABEL_SIZE]; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (copy_from_user(label, arg, sizeof(label))) return -EFAULT; if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) { btrfs_err(root->fs_info, "unable to set label with more than %d bytes", BTRFS_LABEL_SIZE - 1); return -EINVAL; } ret = mnt_want_write_file(file); if (ret) return ret; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_unlock; } spin_lock(&root->fs_info->super_lock); strcpy(super_block->label, label); spin_unlock(&root->fs_info->super_lock); ret = btrfs_commit_transaction(trans, root); out_unlock: mnt_drop_write_file(file); return ret; } #define INIT_FEATURE_FLAGS(suffix) \ { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \ .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \ .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix } static int btrfs_ioctl_get_supported_features(struct file *file, void __user *arg) { static struct btrfs_ioctl_feature_flags features[3] = { INIT_FEATURE_FLAGS(SUPP), INIT_FEATURE_FLAGS(SAFE_SET), INIT_FEATURE_FLAGS(SAFE_CLEAR) }; if (copy_to_user(arg, &features, sizeof(features))) return -EFAULT; return 0; } static int btrfs_ioctl_get_features(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_super_block *super_block = root->fs_info->super_copy; struct btrfs_ioctl_feature_flags features; features.compat_flags = btrfs_super_compat_flags(super_block); features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block); features.incompat_flags = btrfs_super_incompat_flags(super_block); if (copy_to_user(arg, &features, sizeof(features))) return -EFAULT; return 0; } static int check_feature_bits(struct btrfs_root *root, enum btrfs_feature_set set, u64 change_mask, u64 flags, u64 supported_flags, u64 safe_set, u64 safe_clear) { const char *type = btrfs_feature_set_names[set]; char *names; u64 disallowed, unsupported; u64 set_mask = flags & change_mask; u64 clear_mask = ~flags & change_mask; unsupported = set_mask & ~supported_flags; if (unsupported) { names = btrfs_printable_features(set, unsupported); if (names) { btrfs_warn(root->fs_info, "this kernel does not support the %s feature bit%s", names, strchr(names, ',') ? "s" : ""); kfree(names); } else btrfs_warn(root->fs_info, "this kernel does not support %s bits 0x%llx", type, unsupported); return -EOPNOTSUPP; } disallowed = set_mask & ~safe_set; if (disallowed) { names = btrfs_printable_features(set, disallowed); if (names) { btrfs_warn(root->fs_info, "can't set the %s feature bit%s while mounted", names, strchr(names, ',') ? "s" : ""); kfree(names); } else btrfs_warn(root->fs_info, "can't set %s bits 0x%llx while mounted", type, disallowed); return -EPERM; } disallowed = clear_mask & ~safe_clear; if (disallowed) { names = btrfs_printable_features(set, disallowed); if (names) { btrfs_warn(root->fs_info, "can't clear the %s feature bit%s while mounted", names, strchr(names, ',') ? "s" : ""); kfree(names); } else btrfs_warn(root->fs_info, "can't clear %s bits 0x%llx while mounted", type, disallowed); return -EPERM; } return 0; } #define check_feature(root, change_mask, flags, mask_base) \ check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \ BTRFS_FEATURE_ ## mask_base ## _SUPP, \ BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \ BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR) static int btrfs_ioctl_set_features(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; struct btrfs_super_block *super_block = root->fs_info->super_copy; struct btrfs_ioctl_feature_flags flags[2]; struct btrfs_trans_handle *trans; u64 newflags; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (copy_from_user(flags, arg, sizeof(flags))) return -EFAULT; /* Nothing to do */ if (!flags[0].compat_flags && !flags[0].compat_ro_flags && !flags[0].incompat_flags) return 0; ret = check_feature(root, flags[0].compat_flags, flags[1].compat_flags, COMPAT); if (ret) return ret; ret = check_feature(root, flags[0].compat_ro_flags, flags[1].compat_ro_flags, COMPAT_RO); if (ret) return ret; ret = check_feature(root, flags[0].incompat_flags, flags[1].incompat_flags, INCOMPAT); if (ret) return ret; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) return PTR_ERR(trans); spin_lock(&root->fs_info->super_lock); newflags = btrfs_super_compat_flags(super_block); newflags |= flags[0].compat_flags & flags[1].compat_flags; newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags); btrfs_set_super_compat_flags(super_block, newflags); newflags = btrfs_super_compat_ro_flags(super_block); newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags; newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags); btrfs_set_super_compat_ro_flags(super_block, newflags); newflags = btrfs_super_incompat_flags(super_block); newflags |= flags[0].incompat_flags & flags[1].incompat_flags; newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags); btrfs_set_super_incompat_flags(super_block, newflags); spin_unlock(&root->fs_info->super_lock); return btrfs_commit_transaction(trans, root); } long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; void __user *argp = (void __user *)arg; switch (cmd) { case FS_IOC_GETFLAGS: return btrfs_ioctl_getflags(file, argp); case FS_IOC_SETFLAGS: return btrfs_ioctl_setflags(file, argp); case FS_IOC_GETVERSION: return btrfs_ioctl_getversion(file, argp); case FITRIM: return btrfs_ioctl_fitrim(file, argp); case BTRFS_IOC_SNAP_CREATE: return btrfs_ioctl_snap_create(file, argp, 0); case BTRFS_IOC_SNAP_CREATE_V2: return btrfs_ioctl_snap_create_v2(file, argp, 0); case BTRFS_IOC_SUBVOL_CREATE: return btrfs_ioctl_snap_create(file, argp, 1); case BTRFS_IOC_SUBVOL_CREATE_V2: return btrfs_ioctl_snap_create_v2(file, argp, 1); case BTRFS_IOC_SNAP_DESTROY: return btrfs_ioctl_snap_destroy(file, argp); case BTRFS_IOC_SUBVOL_GETFLAGS: return btrfs_ioctl_subvol_getflags(file, argp); case BTRFS_IOC_SUBVOL_SETFLAGS: return btrfs_ioctl_subvol_setflags(file, argp); case BTRFS_IOC_DEFAULT_SUBVOL: return btrfs_ioctl_default_subvol(file, argp); case BTRFS_IOC_DEFRAG: return btrfs_ioctl_defrag(file, NULL); case BTRFS_IOC_DEFRAG_RANGE: return btrfs_ioctl_defrag(file, argp); case BTRFS_IOC_RESIZE: return btrfs_ioctl_resize(file, argp); case BTRFS_IOC_ADD_DEV: return btrfs_ioctl_add_dev(root, argp); case BTRFS_IOC_RM_DEV: return btrfs_ioctl_rm_dev(file, argp); case BTRFS_IOC_FS_INFO: return btrfs_ioctl_fs_info(root, argp); case BTRFS_IOC_DEV_INFO: return btrfs_ioctl_dev_info(root, argp); case BTRFS_IOC_BALANCE: return btrfs_ioctl_balance(file, NULL); case BTRFS_IOC_CLONE: return btrfs_ioctl_clone(file, arg, 0, 0, 0); case BTRFS_IOC_CLONE_RANGE: return btrfs_ioctl_clone_range(file, argp); case BTRFS_IOC_TRANS_START: return btrfs_ioctl_trans_start(file); case BTRFS_IOC_TRANS_END: return btrfs_ioctl_trans_end(file); case BTRFS_IOC_TREE_SEARCH: return btrfs_ioctl_tree_search(file, argp); case BTRFS_IOC_TREE_SEARCH_V2: return btrfs_ioctl_tree_search_v2(file, argp); case BTRFS_IOC_INO_LOOKUP: return btrfs_ioctl_ino_lookup(file, argp); case BTRFS_IOC_INO_PATHS: return btrfs_ioctl_ino_to_path(root, argp); case BTRFS_IOC_LOGICAL_INO: return btrfs_ioctl_logical_to_ino(root, argp); case BTRFS_IOC_SPACE_INFO: return btrfs_ioctl_space_info(root, argp); case BTRFS_IOC_SYNC: { int ret; ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1); if (ret) return ret; ret = btrfs_sync_fs(file_inode(file)->i_sb, 1); /* * The transaction thread may want to do more work, * namely it pokes the cleaner ktread that will start * processing uncleaned subvols. */ wake_up_process(root->fs_info->transaction_kthread); return ret; } case BTRFS_IOC_START_SYNC: return btrfs_ioctl_start_sync(root, argp); case BTRFS_IOC_WAIT_SYNC: return btrfs_ioctl_wait_sync(root, argp); case BTRFS_IOC_SCRUB: return btrfs_ioctl_scrub(file, argp); case BTRFS_IOC_SCRUB_CANCEL: return btrfs_ioctl_scrub_cancel(root, argp); case BTRFS_IOC_SCRUB_PROGRESS: return btrfs_ioctl_scrub_progress(root, argp); case BTRFS_IOC_BALANCE_V2: return btrfs_ioctl_balance(file, argp); case BTRFS_IOC_BALANCE_CTL: return btrfs_ioctl_balance_ctl(root, arg); case BTRFS_IOC_BALANCE_PROGRESS: return btrfs_ioctl_balance_progress(root, argp); case BTRFS_IOC_SET_RECEIVED_SUBVOL: return btrfs_ioctl_set_received_subvol(file, argp); #ifdef CONFIG_64BIT case BTRFS_IOC_SET_RECEIVED_SUBVOL_32: return btrfs_ioctl_set_received_subvol_32(file, argp); #endif case BTRFS_IOC_SEND: return btrfs_ioctl_send(file, argp); case BTRFS_IOC_GET_DEV_STATS: return btrfs_ioctl_get_dev_stats(root, argp); case BTRFS_IOC_QUOTA_CTL: return btrfs_ioctl_quota_ctl(file, argp); case BTRFS_IOC_QGROUP_ASSIGN: return btrfs_ioctl_qgroup_assign(file, argp); case BTRFS_IOC_QGROUP_CREATE: return btrfs_ioctl_qgroup_create(file, argp); case BTRFS_IOC_QGROUP_LIMIT: return btrfs_ioctl_qgroup_limit(file, argp); case BTRFS_IOC_QUOTA_RESCAN: return btrfs_ioctl_quota_rescan(file, argp); case BTRFS_IOC_QUOTA_RESCAN_STATUS: return btrfs_ioctl_quota_rescan_status(file, argp); case BTRFS_IOC_QUOTA_RESCAN_WAIT: return btrfs_ioctl_quota_rescan_wait(file, argp); case BTRFS_IOC_DEV_REPLACE: return btrfs_ioctl_dev_replace(root, argp); case BTRFS_IOC_GET_FSLABEL: return btrfs_ioctl_get_fslabel(file, argp); case BTRFS_IOC_SET_FSLABEL: return btrfs_ioctl_set_fslabel(file, argp); case BTRFS_IOC_FILE_EXTENT_SAME: return btrfs_ioctl_file_extent_same(file, argp); case BTRFS_IOC_GET_SUPPORTED_FEATURES: return btrfs_ioctl_get_supported_features(file, argp); case BTRFS_IOC_GET_FEATURES: return btrfs_ioctl_get_features(file, argp); case BTRFS_IOC_SET_FEATURES: return btrfs_ioctl_set_features(file, argp); } return -ENOTTY; }