/* * 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 <linux/kernel.h> #include <linux/bio.h> #include <linux/buffer_head.h> #include <linux/file.h> #include <linux/fs.h> #include <linux/fsnotify.h> #include <linux/pagemap.h> #include <linux/highmem.h> #include <linux/time.h> #include <linux/init.h> #include <linux/string.h> #include <linux/backing-dev.h> #include <linux/mount.h> #include <linux/mpage.h> #include <linux/namei.h> #include <linux/swap.h> #include <linux/writeback.h> #include <linux/statfs.h> #include <linux/compat.h> #include <linux/bit_spinlock.h> #include <linux/security.h> #include <linux/xattr.h> #include <linux/vmalloc.h> #include <linux/slab.h> #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" /* 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; 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. * * Unlike extN we don't have any flags we don't want to inherit currently. */ void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) { unsigned int flags; if (!dir) return; flags = BTRFS_I(dir)->flags; if (S_ISREG(inode->i_mode)) flags &= ~BTRFS_INODE_DIRSYNC; else if (!S_ISDIR(inode->i_mode)) flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME); BTRFS_I(inode)->flags = flags; 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 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; if (copy_from_user(&flags, arg, sizeof(flags))) return -EFAULT; if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ FS_NOATIME_FL | FS_NODUMP_FL | \ FS_SYNC_FL | FS_DIRSYNC_FL)) return -EOPNOTSUPP; if (!is_owner_or_cap(inode)) return -EACCES; mutex_lock(&inode->i_mutex); 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->f_path.mnt); 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; trans = btrfs_join_transaction(root, 1); BUG_ON(!trans); ret = btrfs_update_inode(trans, root, inode); BUG_ON(ret); btrfs_update_iflags(inode); inode->i_ctime = CURRENT_TIME; btrfs_end_transaction(trans, root); mnt_drop_write(file->f_path.mnt); out_unlock: mutex_unlock(&inode->i_mutex); return 0; } 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 create_subvol(struct btrfs_root *root, struct dentry *dentry, char *name, int namelen) { 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 inode *dir = dentry->d_parent->d_inode; int ret; int err; u64 objectid; u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; u64 index = 0; /* * 1 - inode item * 2 - refs * 1 - root item * 2 - dir items */ ret = btrfs_reserve_metadata_space(root, 6); if (ret) return ret; trans = btrfs_start_transaction(root, 1); BUG_ON(!trans); ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root, 0, &objectid); if (ret) goto fail; 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); 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); BUG_ON(IS_ERR(new_root)); btrfs_record_root_in_trans(trans, new_root); ret = btrfs_create_subvol_root(trans, new_root, new_dirid, BTRFS_I(dir)->block_group); /* * insert the directory item */ ret = btrfs_set_inode_index(dir, &index); BUG_ON(ret); ret = btrfs_insert_dir_item(trans, root, name, namelen, dir->i_ino, &key, BTRFS_FT_DIR, index); if (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, dir->i_ino, index, name, namelen); BUG_ON(ret); d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry)); fail: err = btrfs_commit_transaction(trans, root); if (err && !ret) ret = err; btrfs_unreserve_metadata_space(root, 6); return ret; } static int create_snapshot(struct btrfs_root *root, struct dentry *dentry, char *name, int namelen) { struct inode *inode; struct btrfs_pending_snapshot *pending_snapshot; struct btrfs_trans_handle *trans; int ret; if (!root->ref_cows) return -EINVAL; /* * 1 - inode item * 2 - refs * 1 - root item * 2 - dir items */ ret = btrfs_reserve_metadata_space(root, 6); if (ret) goto fail; pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); if (!pending_snapshot) { ret = -ENOMEM; btrfs_unreserve_metadata_space(root, 6); goto fail; } pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS); if (!pending_snapshot->name) { ret = -ENOMEM; kfree(pending_snapshot); btrfs_unreserve_metadata_space(root, 6); goto fail; } memcpy(pending_snapshot->name, name, namelen); pending_snapshot->name[namelen] = '\0'; pending_snapshot->dentry = dentry; trans = btrfs_start_transaction(root, 1); BUG_ON(!trans); pending_snapshot->root = root; list_add(&pending_snapshot->list, &trans->transaction->pending_snapshots); ret = btrfs_commit_transaction(trans, root); BUG_ON(ret); btrfs_unreserve_metadata_space(root, 6); 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: return ret; } /* 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) { 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 = mnt_want_write(parent->mnt); if (error) goto out_dput; error = btrfs_may_create(dir, dentry); if (error) goto out_drop_write; 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); } else { error = create_subvol(BTRFS_I(dir)->root, dentry, name, namelen); } if (!error) fsnotify_mkdir(dir, dentry); out_up_read: up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); out_drop_write: mnt_drop_write(parent->mnt); out_dput: dput(dentry); out_unlock: mutex_unlock(&dir->i_mutex); return error; } static int should_defrag_range(struct inode *inode, u64 start, u64 len, int thresh, u64 *last_len, u64 *skip, u64 *defrag_end) { 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; int ret = 1; if (thresh == 0) thresh = 256 * 1024; /* * make sure that once we start defragging and extent, we keep on * defragging it */ if (start < *defrag_end) return 1; *skip = 0; /* * 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, GFP_NOFS); em = btrfs_get_extent(inode, NULL, 0, start, len, 0); unlock_extent(io_tree, start, start + len - 1, GFP_NOFS); if (IS_ERR(em)) return 0; } /* this will cover holes, and inline extents */ if (em->block_start >= EXTENT_MAP_LAST_BYTE) ret = 0; /* * we hit a real extent, if it is big don't bother defragging it again */ if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh) ret = 0; /* * 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) { *last_len += len; *defrag_end = extent_map_end(em); } else { *last_len = 0; *skip = extent_map_end(em); *defrag_end = 0; } free_extent_map(em); return ret; } static int btrfs_defrag_file(struct file *file, struct btrfs_ioctl_defrag_range_args *range) { struct inode *inode = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_ordered_extent *ordered; struct page *page; unsigned long last_index; unsigned long ra_pages = root->fs_info->bdi.ra_pages; unsigned long total_read = 0; u64 page_start; u64 page_end; u64 last_len = 0; u64 skip = 0; u64 defrag_end = 0; unsigned long i; int ret; if (inode->i_size == 0) return 0; if (range->start + range->len > range->start) { last_index = min_t(u64, inode->i_size - 1, range->start + range->len - 1) >> PAGE_CACHE_SHIFT; } else { last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT; } i = range->start >> PAGE_CACHE_SHIFT; while (i <= last_index) { if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE, range->extent_thresh, &last_len, &skip, &defrag_end)) { 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 (total_read % ra_pages == 0) { btrfs_force_ra(inode->i_mapping, &file->f_ra, file, i, min(last_index, i + ra_pages - 1)); } total_read++; mutex_lock(&inode->i_mutex); if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) BTRFS_I(inode)->force_compress = 1; ret = btrfs_check_data_free_space(root, inode, PAGE_CACHE_SIZE); if (ret) { ret = -ENOSPC; break; } ret = btrfs_reserve_metadata_for_delalloc(root, inode, 1); if (ret) { btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE); ret = -ENOSPC; break; } again: if (inode->i_size == 0 || i > ((inode->i_size - 1) >> PAGE_CACHE_SHIFT)) { ret = 0; goto err_reservations; } page = grab_cache_page(inode->i_mapping, i); if (!page) goto err_reservations; if (!PageUptodate(page)) { btrfs_readpage(NULL, page); lock_page(page); if (!PageUptodate(page)) { unlock_page(page); page_cache_release(page); goto err_reservations; } } if (page->mapping != inode->i_mapping) { unlock_page(page); page_cache_release(page); goto again; } wait_on_page_writeback(page); if (PageDirty(page)) { btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE); goto loop_unlock; } page_start = (u64)page->index << PAGE_CACHE_SHIFT; page_end = page_start + PAGE_CACHE_SIZE - 1; lock_extent(io_tree, page_start, page_end, GFP_NOFS); ordered = btrfs_lookup_ordered_extent(inode, page_start); if (ordered) { unlock_extent(io_tree, page_start, page_end, GFP_NOFS); unlock_page(page); page_cache_release(page); btrfs_start_ordered_extent(inode, ordered, 1); btrfs_put_ordered_extent(ordered); goto again; } set_page_extent_mapped(page); /* * this makes sure page_mkwrite is called on the * page if it is dirtied again later */ clear_page_dirty_for_io(page); clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING, GFP_NOFS); btrfs_set_extent_delalloc(inode, page_start, page_end, NULL); ClearPageChecked(page); set_page_dirty(page); unlock_extent(io_tree, page_start, page_end, GFP_NOFS); loop_unlock: unlock_page(page); page_cache_release(page); mutex_unlock(&inode->i_mutex); btrfs_unreserve_metadata_for_delalloc(root, inode, 1); balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1); i++; } 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 = 0; mutex_unlock(&inode->i_mutex); } return 0; err_reservations: mutex_unlock(&inode->i_mutex); btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE); btrfs_unreserve_metadata_for_delalloc(root, inode, 1); 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 namelen; int mod = 0; if (root->fs_info->sb->s_flags & MS_RDONLY) return -EROFS; if (!capable(CAP_SYS_ADMIN)) return -EPERM; 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); mutex_lock(&root->fs_info->volume_mutex); 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 "resizing devid %llu\n", (unsigned long long)devid); } device = btrfs_find_device(root, devid, NULL, NULL); if (!device) { printk(KERN_INFO "resizer unable to find device %llu\n", (unsigned long long)devid); ret = -EINVAL; goto out_unlock; } 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_unlock; } } old_size = device->total_bytes; if (mod < 0) { if (new_size > old_size) { ret = -EINVAL; goto out_unlock; } 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_unlock; } if (new_size > device->bdev->bd_inode->i_size) { ret = -EFBIG; goto out_unlock; } do_div(new_size, root->sectorsize); new_size *= root->sectorsize; printk(KERN_INFO "new size for %s is %llu\n", device->name, (unsigned long long)new_size); if (new_size > old_size) { trans = btrfs_start_transaction(root, 1); ret = btrfs_grow_device(trans, device, new_size); btrfs_commit_transaction(trans, root); } else { ret = btrfs_shrink_device(device, new_size); } out_unlock: mutex_unlock(&root->fs_info->volume_mutex); kfree(vol_args); return ret; } static noinline int btrfs_ioctl_snap_create(struct file *file, void __user *arg, int subvol) { struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; struct btrfs_ioctl_vol_args *vol_args; struct file *src_file; int namelen; int ret = 0; if (root->fs_info->sb->s_flags & MS_RDONLY) return -EROFS; 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, '/')) { ret = -EINVAL; goto out; } if (subvol) { ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen, NULL); } else { struct inode *src_inode; src_file = fget(vol_args->fd); if (!src_file) { ret = -EINVAL; goto out; } 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; } ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen, BTRFS_I(src_inode)->root); fput(src_file); } out: kfree(vol_args); 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 found = 0; 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; } 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: *num_found += found; 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(root, 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 = kmalloc(sizeof(*args), GFP_KERNEL); if (!args) return -ENOMEM; if (copy_from_user(args, argp, sizeof(*args))) { kfree(args); return -EFAULT; } 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(root, path); key.objectid = key.offset; key.offset = (u64)-1; dirid = key.objectid; } if (ptr < name) goto out; memcpy(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 = kmalloc(sizeof(*args), GFP_KERNEL); if (!args) return -ENOMEM; if (copy_from_user(args, argp, sizeof(*args))) { kfree(args); return -EFAULT; } 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; if (!capable(CAP_SYS_ADMIN)) return -EPERM; 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->f_path.mnt); 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; if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) { err = -EINVAL; goto out_dput; } dest = BTRFS_I(inode)->root; 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, 1); ret = btrfs_unlink_subvol(trans, root, dir, dest->root_key.objectid, dentry->d_name.name, dentry->d_name.len); BUG_ON(ret); 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); ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root, dest->root_key.objectid); BUG_ON(ret); ret = btrfs_commit_transaction(trans, root); BUG_ON(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->f_path.mnt); 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; ret = mnt_want_write(file->f_path.mnt); if (ret) return ret; switch (inode->i_mode & S_IFMT) { case S_IFDIR: if (!capable(CAP_SYS_ADMIN)) { ret = -EPERM; goto out; } btrfs_defrag_root(root, 0); 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; } btrfs_defrag_file(file, range); kfree(range); break; } out: mnt_drop_write(file->f_path.mnt); 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; 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_init_new_device(root, vol_args->name); kfree(vol_args); 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; 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_rm_device(root, vol_args->name); kfree(vol_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)) return -EINVAL; ret = mnt_want_write(file->f_path.mnt); 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; 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(&inode->i_mutex); mutex_lock(&src->i_mutex); } else { mutex_lock(&src->i_mutex); mutex_lock(&inode->i_mutex); } /* determine range to clone */ ret = -EINVAL; if (off >= src->i_size || off + len > src->i_size) 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 = ((src->i_size + bs-1) & ~(bs-1)) - off; /* verify the end result is block aligned */ if ((off & (bs-1)) || ((off + len) & (bs-1))) goto out_unlock; /* 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, GFP_NOFS); ordered = btrfs_lookup_first_ordered_extent(inode, off+len); if (BTRFS_I(src)->delalloc_bytes == 0 && !ordered) break; unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); if (ordered) btrfs_put_ordered_extent(ordered); btrfs_wait_ordered_range(src, off, off+len); } trans = btrfs_start_transaction(root, 1); BUG_ON(!trans); /* punch hole in destination first */ btrfs_drop_extents(trans, inode, off, off + len, &hint_byte, 1); /* clone data */ key.objectid = src->i_ino; 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(trans, 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 != src->i_ino) 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; 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(root, path); if (key.offset + datal < off || key.offset >= off+len) goto next; memcpy(&new_key, &key, sizeof(new_key)); new_key.objectid = inode->i_ino; new_key.offset = key.offset + destoff - off; if (type == BTRFS_FILE_EXTENT_REG || type == BTRFS_FILE_EXTENT_PREALLOC) { ret = btrfs_insert_empty_item(trans, root, path, &new_key, size); if (ret) 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); if (off > key.offset) { datao += off - key.offset; datal -= off - key.offset; } if (key.offset + datal > off + len) datal = off + len - key.offset; /* 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, inode->i_ino, new_key.offset - datao); BUG_ON(ret); } } 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; goto out; } size -= skip + trim; datal -= skip + trim; ret = btrfs_insert_empty_item(trans, root, path, &new_key, size); if (ret) 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); } next: btrfs_release_path(root, path); key.offset++; } ret = 0; out: btrfs_release_path(root, path); if (ret == 0) { inode->i_mtime = inode->i_ctime = CURRENT_TIME; if (destoff + olen > inode->i_size) btrfs_i_size_write(inode, destoff + olen); BTRFS_I(inode)->flags = BTRFS_I(src)->flags; ret = btrfs_update_inode(trans, root, inode); } btrfs_end_transaction(trans, root); unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); if (ret) vmtruncate(inode, 0); 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->f_path.mnt); 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 = mnt_want_write(file->f_path.mnt); if (ret) goto out; mutex_lock(&root->fs_info->trans_mutex); root->fs_info->open_ioctl_trans++; mutex_unlock(&root->fs_info->trans_mutex); ret = -ENOMEM; trans = btrfs_start_ioctl_transaction(root, 0); if (!trans) goto out_drop; file->private_data = trans; return 0; out_drop: mutex_lock(&root->fs_info->trans_mutex); root->fs_info->open_ioctl_trans--; mutex_unlock(&root->fs_info->trans_mutex); mnt_drop_write(file->f_path.mnt); 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 (!trans) { btrfs_free_path(path); return -ENOMEM; } 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 (!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; } 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_dest; struct btrfs_space_info *info; int alloc_size; int ret = 0; int slot_count = 0; if (copy_from_user(&space_args, (struct btrfs_ioctl_space_args __user *)arg, sizeof(space_args))) return -EFAULT; /* first we count slots */ rcu_read_lock(); list_for_each_entry_rcu(info, &root->fs_info->space_info, list) slot_count++; rcu_read_unlock(); /* space_slots == 0 means they are asking for a count */ if (space_args.space_slots == 0) { space_args.total_spaces = slot_count; goto out; } 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 */ rcu_read_lock(); list_for_each_entry_rcu(info, &root->fs_info->space_info, list) { /* make sure we don't copy more than we allocated * in our buffer */ if (slot_count == 0) break; slot_count--; /* make sure userland has enough room in their buffer */ if (space_args.total_spaces >= space_args.space_slots) break; space.flags = info->flags; space.total_bytes = info->total_bytes; space.used_bytes = info->bytes_used; memcpy(dest, &space, sizeof(space)); dest++; space_args.total_spaces++; } rcu_read_unlock(); user_dest = (struct btrfs_ioctl_space_info *) (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); mutex_lock(&root->fs_info->trans_mutex); root->fs_info->open_ioctl_trans--; mutex_unlock(&root->fs_info->trans_mutex); mnt_drop_write(file->f_path.mnt); return 0; } 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 BTRFS_IOC_SNAP_CREATE: return btrfs_ioctl_snap_create(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_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_BALANCE: return btrfs_balance(root->fs_info->dev_root); 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_SPACE_INFO: return btrfs_ioctl_space_info(root, argp); case BTRFS_IOC_SYNC: btrfs_sync_fs(file->f_dentry->d_sb, 1); return 0; } return -ENOTTY; }