| /* |
| * 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; |
| |
| /* 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(new_root, dentry, trans, 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("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("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; |
| } |
| |
| |
| 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; |
| |
| 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("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: |
| btrfs_defrag_root(root, 0); |
| btrfs_defrag_root(root->fs_info->extent_root, 0); |
| break; |
| case S_IFREG: |
| btrfs_defrag_file(file); |
| break; |
| } |
| |
| return 0; |
| } |
| |
| long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) |
| { |
| struct btrfs_ioctl_vol_args *vol_args; |
| int ret; |
| |
| 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; |
| } |
| |
| long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) |
| { |
| struct btrfs_ioctl_vol_args *vol_args; |
| int ret; |
| |
| 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; |
| } |
| |
| 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)? |
| */ |
| |
| ret = mnt_want_write(file->f_path.mnt); |
| if (ret) |
| return ret; |
| |
| src_file = fget(srcfd); |
| if (!src_file) |
| return -EBADF; |
| 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; |
| |
| printk("final src extent is %llu~%llu\n", off, len); |
| printk("final dst extent is %llu~%llu\n", destoff, len); |
| |
| /* do any pending delalloc/csum calc on src, one way or |
| another, and lock file content */ |
| while (1) { |
| struct btrfs_ordered_extent *ordered; |
| lock_extent(&BTRFS_I(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_CSUM_ITEM_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); |
| printk(" orig disk %llu~%llu data %llu~%llu\n", |
| disko, diskl, datao, datal); |
| |
| 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; |
| printk(" final disk %llu~%llu data %llu~%llu\n", |
| disko, diskl, datao, datal); |
| |
| 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); |
| printk("len %lld skip %lld trim %lld\n", |
| datal, skip, trim); |
| if (comp && (skip || trim)) { |
| printk("btrfs clone_range can't split compressed inline extents yet\n"); |
| 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); |
| } |
| |
| if (btrfs_key_type(&key) == BTRFS_CSUM_ITEM_KEY) { |
| u32 size; |
| struct btrfs_key new_key; |
| u64 coverslen; |
| int coff, clen; |
| |
| size = btrfs_item_size_nr(leaf, slot); |
| coverslen = (size / BTRFS_CRC32_SIZE) << |
| root->fs_info->sb->s_blocksize_bits; |
| printk("csums for %llu~%llu\n", |
| key.offset, coverslen); |
| if (key.offset + coverslen < off || |
| key.offset >= off+len) |
| goto next; |
| |
| read_extent_buffer(leaf, buf, |
| btrfs_item_ptr_offset(leaf, slot), |
| size); |
| btrfs_release_path(root, path); |
| |
| coff = 0; |
| if (off > key.offset) |
| coff = ((off - key.offset) >> |
| root->fs_info->sb->s_blocksize_bits) * |
| BTRFS_CRC32_SIZE; |
| clen = size - coff; |
| if (key.offset + coverslen > off+len) |
| clen -= ((key.offset+coverslen-off-len) >> |
| root->fs_info->sb->s_blocksize_bits) * |
| BTRFS_CRC32_SIZE; |
| printk(" will dup %d~%d of %d\n", |
| coff, clen, size); |
| |
| memcpy(&new_key, &key, sizeof(new_key)); |
| new_key.objectid = inode->i_ino; |
| new_key.offset = key.offset + destoff - off; |
| |
| ret = btrfs_insert_empty_item(trans, root, path, |
| &new_key, clen); |
| if (ret) |
| goto out; |
| |
| leaf = path->nodes[0]; |
| slot = path->slots[0]; |
| write_extent_buffer(leaf, buf + coff, |
| btrfs_item_ptr_offset(leaf, slot), |
| clen); |
| 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); |
| return ret; |
| } |
| |
| long btrfs_ioctl_clone_range(struct file *file, unsigned long argptr) |
| { |
| struct btrfs_ioctl_clone_range_args args; |
| |
| if (copy_from_user(&args, (void *)argptr, 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. |
| */ |
| 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); |
| |
| 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; |
| |
| switch (cmd) { |
| case BTRFS_IOC_SNAP_CREATE: |
| return btrfs_ioctl_snap_create(file, (void __user *)arg, 0); |
| case BTRFS_IOC_SUBVOL_CREATE: |
| return btrfs_ioctl_snap_create(file, (void __user *)arg, 1); |
| case BTRFS_IOC_DEFRAG: |
| return btrfs_ioctl_defrag(file); |
| case BTRFS_IOC_RESIZE: |
| return btrfs_ioctl_resize(root, (void __user *)arg); |
| case BTRFS_IOC_ADD_DEV: |
| return btrfs_ioctl_add_dev(root, (void __user *)arg); |
| case BTRFS_IOC_RM_DEV: |
| return btrfs_ioctl_rm_dev(root, (void __user *)arg); |
| 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, arg); |
| 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; |
| } |