/* * 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 "compat.h" #include "ctree.h" #include "disk-io.h" #include "transaction.h" #include "btrfs_inode.h" #include "ioctl.h" #include "print-tree.h" #include "volumes.h" #include "locking.h" #include "inode-map.h" #include "backref.h" #include "rcu-string.h" /* 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); inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); if (ip->flags & BTRFS_INODE_SYNC) inode->i_flags |= S_SYNC; if (ip->flags & BTRFS_INODE_IMMUTABLE) inode->i_flags |= S_IMMUTABLE; if (ip->flags & BTRFS_INODE_APPEND) inode->i_flags |= S_APPEND; if (ip->flags & BTRFS_INODE_NOATIME) inode->i_flags |= S_NOATIME; if (ip->flags & BTRFS_INODE_DIRSYNC) inode->i_flags |= S_DIRSYNC; } /* * 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; btrfs_update_iflags(inode); } static int btrfs_ioctl_getflags(struct file *file, void __user *arg) { struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode); 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->f_path.dentry->d_inode; 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; 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; if (!inode_owner_or_capable(inode)) return -EACCES; mutex_lock(&inode->i_mutex); ip_oldflags = ip->flags; i_oldflags = inode->i_flags; 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; } } ret = mnt_want_write_file(file); if (ret) 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) ip->flags |= BTRFS_INODE_NODATACOW; 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; } else if (flags & FS_COMPR_FL) { ip->flags |= BTRFS_INODE_COMPRESS; ip->flags &= ~BTRFS_INODE_NOCOMPRESS; } else { 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; } mnt_drop_write_file(file); out_unlock: mutex_unlock(&inode->i_mutex); return ret; } static int btrfs_ioctl_getversion(struct file *file, int __user *arg) { struct inode *inode = file->f_path.dentry->d_inode; 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(fdentry(file)->d_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) 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; } static noinline int create_subvol(struct btrfs_root *root, struct dentry *dentry, char *name, int namelen, u64 *async_transid) { 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 *new_root; struct dentry *parent = dentry->d_parent; struct inode *dir; int ret; int err; u64 objectid; u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; u64 index = 0; ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid); if (ret) return ret; dir = parent->d_inode; /* * 1 - inode item * 2 - refs * 1 - root item * 2 - dir items */ trans = btrfs_start_transaction(root, 6); if (IS_ERR(trans)) return PTR_ERR(trans); leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 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, (unsigned long)btrfs_header_fsid(leaf), BTRFS_FSID_SIZE); write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, (unsigned long)btrfs_header_chunk_tree_uuid(leaf), BTRFS_UUID_SIZE); btrfs_mark_buffer_dirty(leaf); inode_item = &root_item.inode; memset(inode_item, 0, sizeof(*inode_item)); inode_item->generation = cpu_to_le64(1); inode_item->size = cpu_to_le64(3); inode_item->nlink = cpu_to_le32(1); inode_item->nbytes = cpu_to_le64(root->leafsize); inode_item->mode = cpu_to_le32(S_IFDIR | 0755); root_item.flags = 0; root_item.byte_limit = 0; inode_item->flags = cpu_to_le64(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); memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress)); root_item.drop_level = 0; btrfs_tree_unlock(leaf); free_extent_buffer(leaf); leaf = NULL; btrfs_set_root_dirid(&root_item, new_dirid); key.objectid = objectid; key.offset = 0; btrfs_set_key_type(&key, 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, 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); d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry)); fail: if (async_transid) { *async_transid = trans->transid; err = btrfs_commit_transaction_async(trans, root, 1); } else { err = btrfs_commit_transaction(trans, root); } if (err && !ret) ret = err; return ret; } static int create_snapshot(struct btrfs_root *root, struct dentry *dentry, char *name, int namelen, u64 *async_transid, bool readonly) { struct inode *inode; struct btrfs_pending_snapshot *pending_snapshot; struct btrfs_trans_handle *trans; int ret; if (!root->ref_cows) return -EINVAL; pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); if (!pending_snapshot) return -ENOMEM; btrfs_init_block_rsv(&pending_snapshot->block_rsv); pending_snapshot->dentry = dentry; pending_snapshot->root = root; pending_snapshot->readonly = readonly; trans = btrfs_start_transaction(root->fs_info->extent_root, 5); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto fail; } ret = btrfs_snap_reserve_metadata(trans, pending_snapshot); BUG_ON(ret); 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); } else { ret = btrfs_commit_transaction(trans, root->fs_info->extent_root); } BUG_ON(ret); 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; } BUG_ON(!inode); d_instantiate(dentry, inode); ret = 0; fail: kfree(pending_snapshot); return ret; } /* copy of check_sticky in fs/namei.c() * It's inline, so penalty for filesystems that don't use sticky bit is * minimal. */ static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode) { uid_t fsuid = current_fsuid(); if (!(dir->i_mode & S_ISVTX)) return 0; if (inode->i_uid == fsuid) return 0; if (dir->i_uid == fsuid) return 0; return !capable(CAP_FOWNER); } /* 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(victim, dir); error = inode_permission(dir, MAY_WRITE | MAY_EXEC); if (error) return error; if (IS_APPEND(dir)) return -EPERM; if (btrfs_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 (!S_ISDIR(victim->d_inode->i_mode)) return -ENOTDIR; if (IS_ROOT(victim)) return -EBUSY; } else if (S_ISDIR(victim->d_inode->i_mode)) 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 inode *dir = parent->dentry->d_inode; struct dentry *dentry; int error; mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 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; 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, dentry, name, namelen, async_transid, readonly); } else { error = create_subvol(BTRFS_I(dir)->root, dentry, name, namelen, async_transid); } 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, int 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, int thresh) { struct btrfs_path *path; struct btrfs_key min_key; struct btrfs_key max_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; max_key.objectid = ino; max_key.type = (u8)-1; max_key.offset = (u64)-1; path->keep_locks = 1; while(1) { ret = btrfs_search_forward(root, &min_key, &max_key, path, 0, newer_than); if (ret != 0) goto none; 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; } 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) { /* get the big lock and read metadata off disk */ lock_extent(io_tree, start, start + len - 1); em = btrfs_get_extent(inode, NULL, 0, start, len, 0); unlock_extent(io_tree, start, start + len - 1); 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; free_extent_map(next); return ret; } static int should_defrag_range(struct inode *inode, u64 start, int 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, int 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(tree, page_start, page_end); ordered = btrfs_lookup_ordered_extent(inode, page_start); unlock_extent(tree, page_start, page_end); 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, 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); } btrfs_set_extent_delalloc(inode, page_start, page_end - 1, &cached_state); 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 btrfs_super_block *disk_super; struct file_ra_state *ra = NULL; unsigned long last_index; u64 isize = i_size_read(inode); u64 features; 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; int extent_thresh = range->extent_thresh; int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; int cluster = max_cluster; u64 new_align = ~((u64)128 * 1024 - 1); struct page **pages = NULL; if (extent_thresh == 0) extent_thresh = 256 * 1024; 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 (isize == 0) return 0; /* * 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(sizeof(struct page *) * max_cluster, 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 < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT)) { /* * make sure we stop running if someone unmounts * the FS */ if (!(inode->i_sb->s_flags & MS_ACTIVE)) 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 = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 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 (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) BTRFS_I(inode)->force_compress = compress_type; 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); 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_nr(inode->i_mapping, ret); 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 ((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); mutex_lock(&inode->i_mutex); BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; mutex_unlock(&inode->i_mutex); } disk_super = root->fs_info->super_copy; features = btrfs_super_incompat_flags(disk_super); if (range->compress_type == BTRFS_COMPRESS_LZO) { features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO; btrfs_set_super_incompat_flags(disk_super, features); } ret = defrag_count; out_ra: if (!file) kfree(ra); kfree(pages); return ret; } static noinline int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg) { u64 new_size; u64 old_size; u64 devid = 1; struct btrfs_ioctl_vol_args *vol_args; struct btrfs_trans_handle *trans; struct btrfs_device *device = NULL; char *sizestr; char *devstr = NULL; int ret = 0; int mod = 0; if (root->fs_info->sb->s_flags & MS_RDONLY) return -EROFS; if (!capable(CAP_SYS_ADMIN)) return -EPERM; mutex_lock(&root->fs_info->volume_mutex); if (root->fs_info->balance_ctl) { printk(KERN_INFO "btrfs: balance in progress\n"); ret = -EINVAL; goto out; } 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) { char *end; sizestr = devstr + 1; *devstr = '\0'; devstr = vol_args->name; devid = simple_strtoull(devstr, &end, 10); printk(KERN_INFO "btrfs: resizing devid %llu\n", (unsigned long long)devid); } device = btrfs_find_device(root, devid, NULL, NULL); if (!device) { printk(KERN_INFO "btrfs: resizer unable to find device %llu\n", (unsigned long long)devid); ret = -EINVAL; goto out_free; } if (device->fs_devices && device->fs_devices->seeding) { printk(KERN_INFO "btrfs: resizer unable to apply on " "seeding device %llu\n", (unsigned long long)devid); ret = -EINVAL; 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, NULL); if (new_size == 0) { ret = -EINVAL; goto out_free; } } old_size = device->total_bytes; if (mod < 0) { if (new_size > old_size) { ret = -EINVAL; goto out_free; } new_size = old_size - new_size; } else if (mod > 0) { 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), (unsigned long long)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); } out_free: kfree(vol_args); out: mutex_unlock(&root->fs_info->volume_mutex); 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 file *src_file; 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); } else { struct inode *src_inode; src_file = fget(fd); if (!src_file) { ret = -EINVAL; goto out_drop_write; } src_inode = src_file->f_path.dentry->d_inode; if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { printk(KERN_INFO "btrfs: Snapshot src from " "another FS\n"); ret = -EINVAL; fput(src_file); goto out_drop_write; } ret = btrfs_mksubvol(&file->f_path, name, namelen, BTRFS_I(src_inode)->root, transid, readonly); fput(src_file); } 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); 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; 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)) { ret = -EOPNOTSUPP; goto out; } if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) ptr = &transid; if (vol_args->flags & BTRFS_SUBVOL_RDONLY) readonly = true; ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, vol_args->fd, subvol, ptr, readonly); if (ret == 0 && ptr && copy_to_user(arg + offsetof(struct btrfs_ioctl_vol_args_v2, transid), ptr, sizeof(*ptr))) ret = -EFAULT; out: kfree(vol_args); return ret; } static noinline int btrfs_ioctl_subvol_getflags(struct file *file, void __user *arg) { struct inode *inode = fdentry(file)->d_inode; 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 = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; u64 root_flags; u64 flags; int ret = 0; if (root->fs_info->sb->s_flags & MS_RDONLY) return -EROFS; if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) return -EINVAL; if (copy_from_user(&flags, arg, sizeof(flags))) return -EFAULT; if (flags & BTRFS_SUBVOL_CREATE_ASYNC) return -EINVAL; if (flags & ~BTRFS_SUBVOL_RDONLY) return -EOPNOTSUPP; if (!inode_owner_or_capable(inode)) return -EACCES; down_write(&root->fs_info->subvol_sem); /* nothing to do */ if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) goto out; 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 btrfs_set_root_flags(&root->root_item, root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); 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: up_write(&root->fs_info->subvol_sem); 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_key key; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; 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, char *buf, 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); if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) item_len = 0; if (sizeof(sh) + item_len + *sk_offset > BTRFS_SEARCH_ARGS_BUFSIZE) { ret = 1; goto overflow; } btrfs_item_key_to_cpu(leaf, key, i); if (!key_in_sk(key, sk)) continue; sh.objectid = key->objectid; sh.offset = key->offset; sh.type = key->type; sh.len = item_len; sh.transid = found_transid; /* copy search result header */ memcpy(buf + *sk_offset, &sh, sizeof(sh)); *sk_offset += sizeof(sh); if (item_len) { char *p = buf + *sk_offset; /* copy the item */ read_extent_buffer(leaf, p, item_off, item_len); *sk_offset += item_len; } (*num_found)++; if (*num_found >= sk->nr_items) break; } 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; overflow: return ret; } static noinline int search_ioctl(struct inode *inode, struct btrfs_ioctl_search_args *args) { struct btrfs_root *root; struct btrfs_key key; struct btrfs_key max_key; struct btrfs_path *path; struct btrfs_ioctl_search_key *sk = &args->key; struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; int ret; int num_found = 0; unsigned long sk_offset = 0; 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 "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; max_key.objectid = sk->max_objectid; max_key.type = sk->max_type; max_key.offset = sk->max_offset; path->keep_locks = 1; while(1) { ret = btrfs_search_forward(root, &key, &max_key, path, 0, sk->min_transid); if (ret != 0) { if (ret > 0) ret = 0; goto err; } ret = copy_to_sk(root, path, &key, sk, args->buf, &sk_offset, &num_found); btrfs_release_path(path); if (ret || num_found >= sk->nr_items) break; } 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 *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 = fdentry(file)->d_inode; ret = search_ioctl(inode, args); if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) ret = -EFAULT; kfree(args); 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 "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; l = path->nodes[0]; slot = path->slots[0]; if (ret > 0 && slot > 0) slot--; btrfs_item_key_to_cpu(l, &key, slot); if (ret > 0 && (key.objectid != dirid || key.type != BTRFS_INODE_REF_KEY)) { ret = -ENOENT; goto out; } 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) 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; } if (ptr < name) goto out; 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 = fdentry(file)->d_inode; 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 = fdentry(file); 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; 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; mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); 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 non-root 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); err = d_invalidate(dentry); if (err) goto out_unlock; down_write(&root->fs_info->subvol_sem); err = may_destroy_subvol(dest); if (err) goto out_up_write; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { err = PTR_ERR(trans); goto out_up_write; } trans->block_rsv = &root->fs_info->global_block_rsv; 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 (!xchg(&dest->orphan_item_inserted, 1)) { 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; } } out_end_trans: ret = btrfs_end_transaction(trans, root); if (ret && !err) err = ret; inode->i_flags |= S_DEAD; out_up_write: up_write(&root->fs_info->subvol_sem); out_unlock: mutex_unlock(&inode->i_mutex); if (!err) { shrink_dcache_sb(root->fs_info->sb); btrfs_invalidate_inodes(dest); d_delete(dentry); } out_dput: dput(dentry); out_unlock_dir: mutex_unlock(&dir->i_mutex); 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 = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_ioctl_defrag_range_args *range; int ret; if (btrfs_root_readonly(root)) return -EROFS; ret = mnt_want_write_file(file); if (ret) return ret; switch (inode->i_mode & S_IFMT) { case S_IFDIR: if (!capable(CAP_SYS_ADMIN)) { ret = -EPERM; goto out; } ret = btrfs_defrag_root(root, 0); if (ret) goto out; ret = btrfs_defrag_root(root->fs_info->extent_root, 0); 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(fdentry(file)->d_inode, 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; mutex_lock(&root->fs_info->volume_mutex); if (root->fs_info->balance_ctl) { printk(KERN_INFO "btrfs: balance in progress\n"); ret = -EINVAL; goto out; } 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); kfree(vol_args); out: mutex_unlock(&root->fs_info->volume_mutex); return ret; } static long btrfs_ioctl_rm_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 (root->fs_info->sb->s_flags & MS_RDONLY) return -EROFS; mutex_lock(&root->fs_info->volume_mutex); if (root->fs_info->balance_ctl) { printk(KERN_INFO "btrfs: balance in progress\n"); ret = -EINVAL; goto out; } 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_rm_device(root, vol_args->name); kfree(vol_args); out: mutex_unlock(&root->fs_info->volume_mutex); 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; if (!capable(CAP_SYS_ADMIN)) return -EPERM; fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); if (!fi_args) return -ENOMEM; fi_args->num_devices = fs_devices->num_devices; memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); mutex_lock(&fs_devices->device_list_mutex); 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); 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; char empty_uuid[BTRFS_UUID_SIZE] = {0}; if (!capable(CAP_SYS_ADMIN)) return -EPERM; di_args = memdup_user(arg, sizeof(*di_args)); if (IS_ERR(di_args)) return PTR_ERR(di_args); if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0) s_uuid = di_args->uuid; mutex_lock(&fs_devices->device_list_mutex); dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL); mutex_unlock(&fs_devices->device_list_mutex); if (!dev) { ret = -ENODEV; goto out; } di_args->devid = dev->devid; di_args->bytes_used = dev->bytes_used; di_args->total_bytes = dev->total_bytes; 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: if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) ret = -EFAULT; kfree(di_args); return ret; } static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off, u64 olen, u64 destoff) { struct inode *inode = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; struct file *src_file; struct inode *src; struct btrfs_trans_handle *trans; struct btrfs_path *path; struct extent_buffer *leaf; char *buf; struct btrfs_key key; u32 nritems; int slot; int ret; u64 len = olen; u64 bs = root->fs_info->sb->s_blocksize; u64 hint_byte; /* * 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. * - allow ranges within the same file to be cloned (provided * they don't overlap)? */ /* 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 = fget(srcfd); if (!src_file) { ret = -EBADF; goto out_drop_write; } src = src_file->f_dentry->d_inode; ret = -EINVAL; if (src == inode) goto out_fput; /* the src must be open for reading */ if (!(src_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 || BTRFS_I(src)->root != root) goto out_fput; ret = -ENOMEM; buf = vmalloc(btrfs_level_size(root, 0)); if (!buf) goto out_fput; path = btrfs_alloc_path(); if (!path) { vfree(buf); goto out_fput; } path->reada = 2; 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); } /* 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; if (destoff > inode->i_size) { ret = btrfs_cont_expand(inode, inode->i_size, destoff); if (ret) goto out_unlock; } /* truncate page cache pages from target inode range */ truncate_inode_pages_range(&inode->i_data, destoff, PAGE_CACHE_ALIGN(destoff + len) - 1); /* 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(src)->io_tree, off, off+len); ordered = btrfs_lookup_first_ordered_extent(src, off+len); if (!ordered && !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len, EXTENT_DELALLOC, 0, NULL)) break; unlock_extent(&BTRFS_I(src)->io_tree, off, off+len); if (ordered) btrfs_put_ordered_extent(ordered); btrfs_wait_ordered_range(src, off, len); } /* clone data */ key.objectid = btrfs_ino(src); key.type = BTRFS_EXTENT_DATA_KEY; key.offset = 0; while (1) { /* * note the key will change type as we walk through the * tree. */ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; nritems = btrfs_header_nritems(path->nodes[0]); if (path->slots[0] >= nritems) { ret = btrfs_next_leaf(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 (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || key.objectid != btrfs_ino(src)) break; if (btrfs_key_type(&key) == 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 endoff; size = btrfs_item_size_nr(leaf, slot); read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf, slot), size); 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); } btrfs_release_path(path); if (key.offset + datal <= off || key.offset >= off+len) goto next; 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; /* * 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 ------------- | */ /* substract range b */ if (key.offset + datal > off + len) datal = off + len - key.offset; /* substract range a */ if (off > key.offset) { datao += off - key.offset; datal -= off - key.offset; } ret = btrfs_drop_extents(trans, inode, new_key.offset, new_key.offset + datal, &hint_byte, 1); if (ret) { 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); 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, 0); 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; 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; ret = btrfs_drop_extents(trans, inode, new_key.offset, new_key.offset + datal, &hint_byte, 1); if (ret) { 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); } btrfs_mark_buffer_dirty(leaf); btrfs_release_path(path); 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 */ endoff = new_key.offset + datal; 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); } next: btrfs_release_path(path); key.offset++; } ret = 0; out: btrfs_release_path(path); unlock_extent(&BTRFS_I(src)->io_tree, off, off+len); out_unlock: mutex_unlock(&src->i_mutex); mutex_unlock(&inode->i_mutex); vfree(buf); btrfs_free_path(path); out_fput: fput(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 = fdentry(file)->d_inode; 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 = fdentry(file)->d_inode; 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; struct btrfs_super_block *disk_super; u64 features; u64 objectid = 0; u64 dir_id; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (copy_from_user(&objectid, argp, sizeof(objectid))) return -EFAULT; if (!objectid) objectid = root->root_key.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)) return PTR_ERR(new_root); if (btrfs_root_refs(&new_root->root_item) == 0) return -ENOENT; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->leave_spinning = 1; trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } 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); printk(KERN_ERR "Umm, you don't have the default dir item, " "this isn't going to work\n"); return -ENOENT; } 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); disk_super = root->fs_info->super_copy; features = btrfs_super_incompat_flags(disk_super); if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) { features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL; btrfs_set_super_incompat_flags(disk_super, features); } btrfs_end_transaction(trans, root); return 0; } static void 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); } } 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); } /* 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])) { 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); } 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 = fdentry(file)->d_inode; 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 file *file, void __user *argp) { struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; struct btrfs_trans_handle *trans; u64 transid; int ret; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) return PTR_ERR(trans); transid = trans->transid; ret = btrfs_commit_transaction_async(trans, root, 0); if (ret) { btrfs_end_transaction(trans, root); return ret; } if (argp) if (copy_to_user(argp, &transid, sizeof(transid))) return -EFAULT; return 0; } static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp) { struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; 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 btrfs_root *root, void __user *arg) { int ret; struct btrfs_ioctl_scrub_args *sa; if (!capable(CAP_SYS_ADMIN)) return -EPERM; sa = memdup_user(arg, sizeof(*sa)); if (IS_ERR(sa)) return PTR_ERR(sa); ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end, &sa->progress, sa->flags & BTRFS_SCRUB_READONLY); if (copy_to_user(arg, sa, sizeof(*sa))) ret = -EFAULT; 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); } 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_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_SYS_ADMIN)) 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; u64 extent_item_pos; struct btrfs_ioctl_logical_ino_args *loi; struct btrfs_data_container *inodes = NULL; struct btrfs_path *path = NULL; struct btrfs_key key; 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, 4096); inodes = init_data_container(size); if (IS_ERR(inodes)) { ret = PTR_ERR(inodes); inodes = NULL; goto out; } ret = extent_from_logical(root->fs_info, loi->logical, path, &key); btrfs_release_path(path); if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) ret = -ENOENT; if (ret < 0) goto out; extent_item_pos = loi->logical - key.objectid; ret = iterate_extent_inodes(root->fs_info, key.objectid, extent_item_pos, 0, build_ino_list, inodes); 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); kfree(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(fdentry(file)->d_inode)->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_ioctl_balance_args *bargs; struct btrfs_balance_control *bctl; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; ret = mnt_want_write(file->f_path.mnt); if (ret) return ret; mutex_lock(&fs_info->volume_mutex); mutex_lock(&fs_info->balance_mutex); if (arg) { bargs = memdup_user(arg, sizeof(*bargs)); if (IS_ERR(bargs)) { ret = PTR_ERR(bargs); goto out; } 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: ret = btrfs_balance(bctl, bargs); /* * bctl is freed in __cancel_balance or in free_fs_info if * restriper was paused all the way until unmount */ if (arg) { if (copy_to_user(arg, bargs, sizeof(*bargs))) ret = -EFAULT; } out_bargs: kfree(bargs); out: mutex_unlock(&fs_info->balance_mutex); mutex_unlock(&fs_info->volume_mutex); mnt_drop_write(file->f_path.mnt); 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; } long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->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_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(root, argp); case BTRFS_IOC_ADD_DEV: return btrfs_ioctl_add_dev(root, argp); case BTRFS_IOC_RM_DEV: return btrfs_ioctl_rm_dev(root, 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_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: btrfs_sync_fs(file->f_dentry->d_sb, 1); return 0; case BTRFS_IOC_START_SYNC: return btrfs_ioctl_start_sync(file, argp); case BTRFS_IOC_WAIT_SYNC: return btrfs_ioctl_wait_sync(file, argp); case BTRFS_IOC_SCRUB: return btrfs_ioctl_scrub(root, 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_GET_DEV_STATS: return btrfs_ioctl_get_dev_stats(root, argp); } return -ENOTTY; }