/* * 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/smp_lock.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/version.h> #include <linux/xattr.h> #include <linux/vmalloc.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" 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 = root; struct inode *dir; int ret; int err; u64 objectid; u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; u64 index = 0; unsigned long nr = 1; ret = btrfs_check_free_space(root, 1, 0); if (ret) goto fail_commit; 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, trans->transid, 0, 0, 0); if (IS_ERR(leaf)) { ret = PTR_ERR(leaf); goto fail; } btrfs_set_header_nritems(leaf, 0); btrfs_set_header_level(leaf, 0); btrfs_set_header_bytenr(leaf, leaf->start); btrfs_set_header_generation(leaf, trans->transid); btrfs_set_header_owner(leaf, objectid); write_extent_buffer(leaf, root->fs_info->fsid, (unsigned long)btrfs_header_fsid(leaf), BTRFS_FSID_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, 0); 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 = 1; 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; /* * insert the directory item */ key.offset = (u64)-1; dir = dentry->d_parent->d_inode; 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); /* add the backref first */ ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, objectid, BTRFS_ROOT_BACKREF_KEY, root->root_key.objectid, dir->i_ino, index, name, namelen); BUG_ON(ret); /* now add the forward ref */ ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, root->root_key.objectid, BTRFS_ROOT_REF_KEY, objectid, dir->i_ino, index, name, namelen); BUG_ON(ret); ret = btrfs_commit_transaction(trans, root); if (ret) goto fail_commit; new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); BUG_ON(!new_root); trans = btrfs_start_transaction(new_root, 1); BUG_ON(!trans); ret = btrfs_create_subvol_root(trans, new_root, dentry, new_dirid, BTRFS_I(dir)->block_group); if (ret) goto fail; fail: nr = trans->blocks_used; err = btrfs_commit_transaction(trans, new_root); if (err && !ret) ret = err; fail_commit: btrfs_btree_balance_dirty(root, nr); return ret; } static int create_snapshot(struct btrfs_root *root, struct dentry *dentry, char *name, int namelen) { struct btrfs_pending_snapshot *pending_snapshot; struct btrfs_trans_handle *trans; int ret = 0; int err; unsigned long nr = 0; if (!root->ref_cows) return -EINVAL; ret = btrfs_check_free_space(root, 1, 0); if (ret) goto fail_unlock; pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); if (!pending_snapshot) { ret = -ENOMEM; goto fail_unlock; } pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS); if (!pending_snapshot->name) { ret = -ENOMEM; kfree(pending_snapshot); goto fail_unlock; } 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); err = btrfs_commit_transaction(trans, root); fail_unlock: btrfs_btree_balance_dirty(root, nr); 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 mode, int namelen, struct btrfs_root *snap_src) { struct dentry *dentry; int error; mutex_lock_nested(&parent->dentry->d_inode->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; if (!IS_POSIXACL(parent->dentry->d_inode)) mode &= ~current->fs->umask; error = mnt_want_write(parent->mnt); if (error) goto out_dput; error = btrfs_may_create(parent->dentry->d_inode, dentry); if (error) goto out_drop_write; /* * Actually perform the low-level subvolume creation after all * this VFS fuzz. * * Eventually we want to pass in an inode under which we create this * subvolume, but for now all are under the filesystem root. * * Also we should pass on the mode eventually to allow creating new * subvolume with specific mode bits. */ if (snap_src) { struct dentry *dir = dentry->d_parent; struct dentry *test = dir->d_parent; struct btrfs_path *path = btrfs_alloc_path(); int ret; u64 test_oid; u64 parent_oid = BTRFS_I(dir->d_inode)->root->root_key.objectid; test_oid = snap_src->root_key.objectid; ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, path, parent_oid, test_oid); if (ret == 0) goto create; btrfs_release_path(snap_src->fs_info->tree_root, path); /* we need to make sure we aren't creating a directory loop * by taking a snapshot of something that has our current * subvol in its directory tree. So, this loops through * the dentries and checks the forward refs for each subvolume * to see if is references the subvolume where we are * placing this new snapshot. */ while (1) { if (!test || dir == snap_src->fs_info->sb->s_root || test == snap_src->fs_info->sb->s_root || test->d_inode->i_sb != snap_src->fs_info->sb) { break; } if (S_ISLNK(test->d_inode->i_mode)) { printk(KERN_INFO "Btrfs symlink in snapshot " "path, failed\n"); error = -EMLINK; btrfs_free_path(path); goto out_drop_write; } test_oid = BTRFS_I(test->d_inode)->root->root_key.objectid; ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, path, test_oid, parent_oid); if (ret == 0) { printk(KERN_INFO "Btrfs snapshot creation " "failed, looping\n"); error = -EMLINK; btrfs_free_path(path); goto out_drop_write; } btrfs_release_path(snap_src->fs_info->tree_root, path); test = test->d_parent; } create: btrfs_free_path(path); error = create_snapshot(snap_src, dentry, name, namelen); } else { error = create_subvol(BTRFS_I(parent->dentry->d_inode)->root, dentry, name, namelen); } if (error) goto out_drop_write; fsnotify_mkdir(parent->dentry->d_inode, dentry); out_drop_write: mnt_drop_write(parent->mnt); out_dput: dput(dentry); out_unlock: mutex_unlock(&parent->dentry->d_inode->i_mutex); return error; } static int btrfs_defrag_file(struct file *file) { 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; unsigned long i; int ret; ret = btrfs_check_free_space(root, inode->i_size, 0); if (ret) return -ENOSPC; mutex_lock(&inode->i_mutex); last_index = inode->i_size >> PAGE_CACHE_SHIFT; for (i = 0; i <= last_index; i++) { 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++; again: page = grab_cache_page(inode->i_mapping, i); if (!page) goto out_unlock; if (!PageUptodate(page)) { btrfs_readpage(NULL, page); lock_page(page); if (!PageUptodate(page)) { unlock_page(page); page_cache_release(page); goto out_unlock; } } wait_on_page_writeback(page); 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); btrfs_set_extent_delalloc(inode, page_start, page_end); unlock_extent(io_tree, page_start, page_end, GFP_NOFS); set_page_dirty(page); unlock_page(page); page_cache_release(page); balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1); } out_unlock: mutex_unlock(&inode->i_mutex); return 0; } /* * Called inside transaction, so use GFP_NOFS */ static 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 = kmalloc(sizeof(*vol_args), GFP_NOFS); if (!vol_args) return -ENOMEM; if (copy_from_user(vol_args, arg, sizeof(*vol_args))) { ret = -EFAULT; goto out; } 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", devid); } device = btrfs_find_device(root, devid, NULL, NULL); if (!device) { printk(KERN_INFO "resizer unable to find device %llu\n", 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 = btrfs_parse_size(sizestr); 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); out: 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 btrfs_dir_item *di; struct btrfs_path *path; struct file *src_file; u64 root_dirid; int namelen; int ret = 0; if (root->fs_info->sb->s_flags & MS_RDONLY) return -EROFS; vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS); if (!vol_args) return -ENOMEM; if (copy_from_user(vol_args, arg, sizeof(*vol_args))) { ret = -EFAULT; goto out; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; namelen = strlen(vol_args->name); if (strchr(vol_args->name, '/')) { ret = -EINVAL; goto out; } path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } root_dirid = root->fs_info->sb->s_root->d_inode->i_ino, di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path, root_dirid, vol_args->name, namelen, 0); btrfs_free_path(path); if (di && !IS_ERR(di)) { ret = -EEXIST; goto out; } if (IS_ERR(di)) { ret = PTR_ERR(di); goto out; } if (subvol) { ret = btrfs_mksubvol(&file->f_path, vol_args->name, file->f_path.dentry->d_inode->i_mode, 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, file->f_path.dentry->d_inode->i_mode, namelen, BTRFS_I(src_inode)->root); fput(src_file); } out: kfree(vol_args); return ret; } static int btrfs_ioctl_defrag(struct file *file) { struct inode *inode = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; 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; } btrfs_defrag_file(file); 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 = kmalloc(sizeof(*vol_args), GFP_NOFS); if (!vol_args) return -ENOMEM; if (copy_from_user(vol_args, arg, sizeof(*vol_args))) { ret = -EFAULT; goto out; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; ret = btrfs_init_new_device(root, vol_args->name); out: 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 = kmalloc(sizeof(*vol_args), GFP_NOFS); if (!vol_args) return -ENOMEM; if (copy_from_user(vol_args, arg, sizeof(*vol_args))) { ret = -EFAULT; goto out; } vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; ret = btrfs_rm_device(root, vol_args->name); out: kfree(vol_args); return ret; } static 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; 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, root, inode, off, off+len, 0, &hint_byte); /* 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) { 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) { 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 + datao + datal + key.offset > off + len) datal = off + len - key.offset - datao; /* 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, leaf->start, root->root_key.objectid, trans->transid, inode->i_ino); 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 = 0; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (file->private_data) { ret = -EINPROGRESS; 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); trans = btrfs_start_ioctl_transaction(root, 0); if (trans) file->private_data = trans; else ret = -ENOMEM; /*printk(KERN_INFO "btrfs_ioctl_trans_start on %p\n", file);*/ out: 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; int ret = 0; trans = file->private_data; if (!trans) { ret = -EINVAL; goto out; } btrfs_end_transaction(trans, root); file->private_data = NULL; 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; } 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 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_DEFRAG: return btrfs_ioctl_defrag(file); 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_SYNC: btrfs_sync_fs(file->f_dentry->d_sb, 1); return 0; } return -ENOTTY; }