| /* |
| * 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 <linux/blkdev.h> |
| #include <linux/uuid.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" |
| #include "inode-map.h" |
| #include "backref.h" |
| #include "rcu-string.h" |
| #include "send.h" |
| |
| /* Mask out flags that are inappropriate for the given type of inode. */ |
| static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags) |
| { |
| if (S_ISDIR(mode)) |
| return flags; |
| else if (S_ISREG(mode)) |
| return flags & ~FS_DIRSYNC_FL; |
| else |
| return flags & (FS_NODUMP_FL | FS_NOATIME_FL); |
| } |
| |
| /* |
| * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl. |
| */ |
| static unsigned int btrfs_flags_to_ioctl(unsigned int flags) |
| { |
| unsigned int iflags = 0; |
| |
| if (flags & BTRFS_INODE_SYNC) |
| iflags |= FS_SYNC_FL; |
| if (flags & BTRFS_INODE_IMMUTABLE) |
| iflags |= FS_IMMUTABLE_FL; |
| if (flags & BTRFS_INODE_APPEND) |
| iflags |= FS_APPEND_FL; |
| if (flags & BTRFS_INODE_NODUMP) |
| iflags |= FS_NODUMP_FL; |
| if (flags & BTRFS_INODE_NOATIME) |
| iflags |= FS_NOATIME_FL; |
| if (flags & BTRFS_INODE_DIRSYNC) |
| iflags |= FS_DIRSYNC_FL; |
| if (flags & BTRFS_INODE_NODATACOW) |
| iflags |= FS_NOCOW_FL; |
| |
| if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS)) |
| iflags |= FS_COMPR_FL; |
| else if (flags & BTRFS_INODE_NOCOMPRESS) |
| iflags |= FS_NOCOMP_FL; |
| |
| return iflags; |
| } |
| |
| /* |
| * Update inode->i_flags based on the btrfs internal flags. |
| */ |
| void btrfs_update_iflags(struct inode *inode) |
| { |
| struct btrfs_inode *ip = BTRFS_I(inode); |
| |
| inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); |
| |
| if (ip->flags & BTRFS_INODE_SYNC) |
| inode->i_flags |= S_SYNC; |
| if (ip->flags & BTRFS_INODE_IMMUTABLE) |
| inode->i_flags |= S_IMMUTABLE; |
| if (ip->flags & BTRFS_INODE_APPEND) |
| inode->i_flags |= S_APPEND; |
| if (ip->flags & BTRFS_INODE_NOATIME) |
| inode->i_flags |= S_NOATIME; |
| if (ip->flags & BTRFS_INODE_DIRSYNC) |
| inode->i_flags |= S_DIRSYNC; |
| } |
| |
| /* |
| * Inherit flags from the parent inode. |
| * |
| * Currently only the compression flags and the cow flags are inherited. |
| */ |
| void btrfs_inherit_iflags(struct inode *inode, struct inode *dir) |
| { |
| unsigned int flags; |
| |
| if (!dir) |
| return; |
| |
| flags = BTRFS_I(dir)->flags; |
| |
| if (flags & BTRFS_INODE_NOCOMPRESS) { |
| BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS; |
| BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; |
| } else if (flags & BTRFS_INODE_COMPRESS) { |
| BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS; |
| BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS; |
| } |
| |
| if (flags & BTRFS_INODE_NODATACOW) |
| BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; |
| |
| btrfs_update_iflags(inode); |
| } |
| |
| static int btrfs_ioctl_getflags(struct file *file, void __user *arg) |
| { |
| struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode); |
| unsigned int flags = btrfs_flags_to_ioctl(ip->flags); |
| |
| if (copy_to_user(arg, &flags, sizeof(flags))) |
| return -EFAULT; |
| return 0; |
| } |
| |
| static int check_flags(unsigned int flags) |
| { |
| if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ |
| FS_NOATIME_FL | FS_NODUMP_FL | \ |
| FS_SYNC_FL | FS_DIRSYNC_FL | \ |
| FS_NOCOMP_FL | FS_COMPR_FL | |
| FS_NOCOW_FL)) |
| return -EOPNOTSUPP; |
| |
| if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| static int btrfs_ioctl_setflags(struct file *file, void __user *arg) |
| { |
| struct inode *inode = file->f_path.dentry->d_inode; |
| struct btrfs_inode *ip = BTRFS_I(inode); |
| struct btrfs_root *root = ip->root; |
| struct btrfs_trans_handle *trans; |
| unsigned int flags, oldflags; |
| int ret; |
| u64 ip_oldflags; |
| unsigned int i_oldflags; |
| |
| if (btrfs_root_readonly(root)) |
| return -EROFS; |
| |
| if (copy_from_user(&flags, arg, sizeof(flags))) |
| return -EFAULT; |
| |
| ret = check_flags(flags); |
| if (ret) |
| return ret; |
| |
| if (!inode_owner_or_capable(inode)) |
| return -EACCES; |
| |
| ret = mnt_want_write_file(file); |
| if (ret) |
| return ret; |
| |
| mutex_lock(&inode->i_mutex); |
| |
| ip_oldflags = ip->flags; |
| i_oldflags = inode->i_flags; |
| |
| flags = btrfs_mask_flags(inode->i_mode, flags); |
| oldflags = btrfs_flags_to_ioctl(ip->flags); |
| if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { |
| if (!capable(CAP_LINUX_IMMUTABLE)) { |
| ret = -EPERM; |
| goto out_unlock; |
| } |
| } |
| |
| if (flags & FS_SYNC_FL) |
| ip->flags |= BTRFS_INODE_SYNC; |
| else |
| ip->flags &= ~BTRFS_INODE_SYNC; |
| if (flags & FS_IMMUTABLE_FL) |
| ip->flags |= BTRFS_INODE_IMMUTABLE; |
| else |
| ip->flags &= ~BTRFS_INODE_IMMUTABLE; |
| if (flags & FS_APPEND_FL) |
| ip->flags |= BTRFS_INODE_APPEND; |
| else |
| ip->flags &= ~BTRFS_INODE_APPEND; |
| if (flags & FS_NODUMP_FL) |
| ip->flags |= BTRFS_INODE_NODUMP; |
| else |
| ip->flags &= ~BTRFS_INODE_NODUMP; |
| if (flags & FS_NOATIME_FL) |
| ip->flags |= BTRFS_INODE_NOATIME; |
| else |
| ip->flags &= ~BTRFS_INODE_NOATIME; |
| if (flags & FS_DIRSYNC_FL) |
| ip->flags |= BTRFS_INODE_DIRSYNC; |
| else |
| ip->flags &= ~BTRFS_INODE_DIRSYNC; |
| if (flags & FS_NOCOW_FL) |
| ip->flags |= BTRFS_INODE_NODATACOW; |
| else |
| ip->flags &= ~BTRFS_INODE_NODATACOW; |
| |
| /* |
| * The COMPRESS flag can only be changed by users, while the NOCOMPRESS |
| * flag may be changed automatically if compression code won't make |
| * things smaller. |
| */ |
| if (flags & FS_NOCOMP_FL) { |
| ip->flags &= ~BTRFS_INODE_COMPRESS; |
| ip->flags |= BTRFS_INODE_NOCOMPRESS; |
| } else if (flags & FS_COMPR_FL) { |
| ip->flags |= BTRFS_INODE_COMPRESS; |
| ip->flags &= ~BTRFS_INODE_NOCOMPRESS; |
| } else { |
| ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); |
| } |
| |
| trans = btrfs_start_transaction(root, 1); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| goto out_drop; |
| } |
| |
| btrfs_update_iflags(inode); |
| inode_inc_iversion(inode); |
| inode->i_ctime = CURRENT_TIME; |
| ret = btrfs_update_inode(trans, root, inode); |
| |
| btrfs_end_transaction(trans, root); |
| out_drop: |
| if (ret) { |
| ip->flags = ip_oldflags; |
| inode->i_flags = i_oldflags; |
| } |
| |
| out_unlock: |
| mutex_unlock(&inode->i_mutex); |
| mnt_drop_write_file(file); |
| return ret; |
| } |
| |
| static int btrfs_ioctl_getversion(struct file *file, int __user *arg) |
| { |
| struct inode *inode = file->f_path.dentry->d_inode; |
| |
| return put_user(inode->i_generation, arg); |
| } |
| |
| static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) |
| { |
| struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb); |
| struct btrfs_device *device; |
| struct request_queue *q; |
| struct fstrim_range range; |
| u64 minlen = ULLONG_MAX; |
| u64 num_devices = 0; |
| u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy); |
| int ret; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| rcu_read_lock(); |
| list_for_each_entry_rcu(device, &fs_info->fs_devices->devices, |
| dev_list) { |
| if (!device->bdev) |
| continue; |
| q = bdev_get_queue(device->bdev); |
| if (blk_queue_discard(q)) { |
| num_devices++; |
| minlen = min((u64)q->limits.discard_granularity, |
| minlen); |
| } |
| } |
| rcu_read_unlock(); |
| |
| if (!num_devices) |
| return -EOPNOTSUPP; |
| if (copy_from_user(&range, arg, sizeof(range))) |
| return -EFAULT; |
| if (range.start > total_bytes) |
| return -EINVAL; |
| |
| range.len = min(range.len, total_bytes - range.start); |
| range.minlen = max(range.minlen, minlen); |
| ret = btrfs_trim_fs(fs_info->tree_root, &range); |
| if (ret < 0) |
| return ret; |
| |
| if (copy_to_user(arg, &range, sizeof(range))) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| static noinline int create_subvol(struct btrfs_root *root, |
| struct dentry *dentry, |
| char *name, int namelen, |
| u64 *async_transid, |
| struct btrfs_qgroup_inherit **inherit) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_key key; |
| struct btrfs_root_item root_item; |
| struct btrfs_inode_item *inode_item; |
| struct extent_buffer *leaf; |
| struct btrfs_root *new_root; |
| struct dentry *parent = dentry->d_parent; |
| struct inode *dir; |
| struct timespec cur_time = CURRENT_TIME; |
| int ret; |
| int err; |
| u64 objectid; |
| u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; |
| u64 index = 0; |
| uuid_le new_uuid; |
| |
| ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid); |
| if (ret) |
| return ret; |
| |
| dir = parent->d_inode; |
| |
| /* |
| * 1 - inode item |
| * 2 - refs |
| * 1 - root item |
| * 2 - dir items |
| */ |
| trans = btrfs_start_transaction(root, 6); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, |
| inherit ? *inherit : NULL); |
| 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); |
| |
| memset(&root_item, 0, sizeof(root_item)); |
| |
| inode_item = &root_item.inode; |
| inode_item->generation = cpu_to_le64(1); |
| inode_item->size = cpu_to_le64(3); |
| inode_item->nlink = cpu_to_le32(1); |
| inode_item->nbytes = cpu_to_le64(root->leafsize); |
| inode_item->mode = cpu_to_le32(S_IFDIR | 0755); |
| |
| root_item.flags = 0; |
| root_item.byte_limit = 0; |
| inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT); |
| |
| btrfs_set_root_bytenr(&root_item, leaf->start); |
| btrfs_set_root_generation(&root_item, trans->transid); |
| btrfs_set_root_level(&root_item, 0); |
| btrfs_set_root_refs(&root_item, 1); |
| btrfs_set_root_used(&root_item, leaf->len); |
| btrfs_set_root_last_snapshot(&root_item, 0); |
| |
| btrfs_set_root_generation_v2(&root_item, |
| btrfs_root_generation(&root_item)); |
| uuid_le_gen(&new_uuid); |
| memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE); |
| root_item.otime.sec = cpu_to_le64(cur_time.tv_sec); |
| root_item.otime.nsec = cpu_to_le32(cur_time.tv_nsec); |
| root_item.ctime = root_item.otime; |
| btrfs_set_root_ctransid(&root_item, trans->transid); |
| btrfs_set_root_otransid(&root_item, trans->transid); |
| |
| btrfs_tree_unlock(leaf); |
| free_extent_buffer(leaf); |
| leaf = NULL; |
| |
| btrfs_set_root_dirid(&root_item, new_dirid); |
| |
| key.objectid = objectid; |
| key.offset = 0; |
| btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); |
| ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, |
| &root_item); |
| if (ret) |
| goto fail; |
| |
| key.offset = (u64)-1; |
| new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); |
| if (IS_ERR(new_root)) { |
| btrfs_abort_transaction(trans, root, PTR_ERR(new_root)); |
| ret = PTR_ERR(new_root); |
| goto fail; |
| } |
| |
| btrfs_record_root_in_trans(trans, new_root); |
| |
| ret = btrfs_create_subvol_root(trans, new_root, new_dirid); |
| if (ret) { |
| /* We potentially lose an unused inode item here */ |
| btrfs_abort_transaction(trans, root, ret); |
| goto fail; |
| } |
| |
| /* |
| * insert the directory item |
| */ |
| ret = btrfs_set_inode_index(dir, &index); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto fail; |
| } |
| |
| ret = btrfs_insert_dir_item(trans, root, |
| name, namelen, dir, &key, |
| BTRFS_FT_DIR, index); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto fail; |
| } |
| |
| btrfs_i_size_write(dir, dir->i_size + namelen * 2); |
| ret = btrfs_update_inode(trans, root, dir); |
| BUG_ON(ret); |
| |
| ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, |
| objectid, root->root_key.objectid, |
| btrfs_ino(dir), index, name, namelen); |
| |
| BUG_ON(ret); |
| |
| d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry)); |
| fail: |
| if (async_transid) { |
| *async_transid = trans->transid; |
| err = btrfs_commit_transaction_async(trans, root, 1); |
| } else { |
| err = btrfs_commit_transaction(trans, root); |
| } |
| if (err && !ret) |
| ret = err; |
| return ret; |
| } |
| |
| static int create_snapshot(struct btrfs_root *root, struct dentry *dentry, |
| char *name, int namelen, u64 *async_transid, |
| bool readonly, struct btrfs_qgroup_inherit **inherit) |
| { |
| struct inode *inode; |
| struct btrfs_pending_snapshot *pending_snapshot; |
| struct btrfs_trans_handle *trans; |
| int ret; |
| |
| if (!root->ref_cows) |
| return -EINVAL; |
| |
| pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); |
| if (!pending_snapshot) |
| return -ENOMEM; |
| |
| btrfs_init_block_rsv(&pending_snapshot->block_rsv); |
| pending_snapshot->dentry = dentry; |
| pending_snapshot->root = root; |
| pending_snapshot->readonly = readonly; |
| if (inherit) { |
| pending_snapshot->inherit = *inherit; |
| *inherit = NULL; /* take responsibility to free it */ |
| } |
| |
| trans = btrfs_start_transaction(root->fs_info->extent_root, 5); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| goto fail; |
| } |
| |
| ret = btrfs_snap_reserve_metadata(trans, pending_snapshot); |
| BUG_ON(ret); |
| |
| spin_lock(&root->fs_info->trans_lock); |
| list_add(&pending_snapshot->list, |
| &trans->transaction->pending_snapshots); |
| spin_unlock(&root->fs_info->trans_lock); |
| if (async_transid) { |
| *async_transid = trans->transid; |
| ret = btrfs_commit_transaction_async(trans, |
| root->fs_info->extent_root, 1); |
| } else { |
| ret = btrfs_commit_transaction(trans, |
| root->fs_info->extent_root); |
| } |
| BUG_ON(ret); |
| |
| ret = pending_snapshot->error; |
| if (ret) |
| goto fail; |
| |
| ret = btrfs_orphan_cleanup(pending_snapshot->snap); |
| if (ret) |
| goto fail; |
| |
| inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry); |
| if (IS_ERR(inode)) { |
| ret = PTR_ERR(inode); |
| goto fail; |
| } |
| BUG_ON(!inode); |
| d_instantiate(dentry, inode); |
| ret = 0; |
| fail: |
| kfree(pending_snapshot); |
| return ret; |
| } |
| |
| /* copy of check_sticky in fs/namei.c() |
| * It's inline, so penalty for filesystems that don't use sticky bit is |
| * minimal. |
| */ |
| static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode) |
| { |
| uid_t fsuid = current_fsuid(); |
| |
| if (!(dir->i_mode & S_ISVTX)) |
| return 0; |
| if (inode->i_uid == fsuid) |
| return 0; |
| if (dir->i_uid == fsuid) |
| return 0; |
| return !capable(CAP_FOWNER); |
| } |
| |
| /* copy of may_delete in fs/namei.c() |
| * Check whether we can remove a link victim from directory dir, check |
| * whether the type of victim is right. |
| * 1. We can't do it if dir is read-only (done in permission()) |
| * 2. We should have write and exec permissions on dir |
| * 3. We can't remove anything from append-only dir |
| * 4. We can't do anything with immutable dir (done in permission()) |
| * 5. If the sticky bit on dir is set we should either |
| * a. be owner of dir, or |
| * b. be owner of victim, or |
| * c. have CAP_FOWNER capability |
| * 6. If the victim is append-only or immutable we can't do antyhing with |
| * links pointing to it. |
| * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. |
| * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. |
| * 9. We can't remove a root or mountpoint. |
| * 10. We don't allow removal of NFS sillyrenamed files; it's handled by |
| * nfs_async_unlink(). |
| */ |
| |
| static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir) |
| { |
| int error; |
| |
| if (!victim->d_inode) |
| return -ENOENT; |
| |
| BUG_ON(victim->d_parent->d_inode != dir); |
| audit_inode_child(victim, dir); |
| |
| error = inode_permission(dir, MAY_WRITE | MAY_EXEC); |
| if (error) |
| return error; |
| if (IS_APPEND(dir)) |
| return -EPERM; |
| if (btrfs_check_sticky(dir, victim->d_inode)|| |
| IS_APPEND(victim->d_inode)|| |
| IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) |
| return -EPERM; |
| if (isdir) { |
| if (!S_ISDIR(victim->d_inode->i_mode)) |
| return -ENOTDIR; |
| if (IS_ROOT(victim)) |
| return -EBUSY; |
| } else if (S_ISDIR(victim->d_inode->i_mode)) |
| return -EISDIR; |
| if (IS_DEADDIR(dir)) |
| return -ENOENT; |
| if (victim->d_flags & DCACHE_NFSFS_RENAMED) |
| return -EBUSY; |
| return 0; |
| } |
| |
| /* copy of may_create in fs/namei.c() */ |
| static inline int btrfs_may_create(struct inode *dir, struct dentry *child) |
| { |
| if (child->d_inode) |
| return -EEXIST; |
| if (IS_DEADDIR(dir)) |
| return -ENOENT; |
| return inode_permission(dir, MAY_WRITE | MAY_EXEC); |
| } |
| |
| /* |
| * Create a new subvolume below @parent. This is largely modeled after |
| * sys_mkdirat and vfs_mkdir, but we only do a single component lookup |
| * inside this filesystem so it's quite a bit simpler. |
| */ |
| static noinline int btrfs_mksubvol(struct path *parent, |
| char *name, int namelen, |
| struct btrfs_root *snap_src, |
| u64 *async_transid, bool readonly, |
| struct btrfs_qgroup_inherit **inherit) |
| { |
| struct inode *dir = parent->dentry->d_inode; |
| struct dentry *dentry; |
| int error; |
| |
| mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); |
| |
| dentry = lookup_one_len(name, parent->dentry, namelen); |
| error = PTR_ERR(dentry); |
| if (IS_ERR(dentry)) |
| goto out_unlock; |
| |
| error = -EEXIST; |
| if (dentry->d_inode) |
| goto out_dput; |
| |
| error = btrfs_may_create(dir, dentry); |
| if (error) |
| goto out_dput; |
| |
| down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); |
| |
| if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) |
| goto out_up_read; |
| |
| if (snap_src) { |
| error = create_snapshot(snap_src, dentry, name, namelen, |
| async_transid, readonly, inherit); |
| } else { |
| error = create_subvol(BTRFS_I(dir)->root, dentry, |
| name, namelen, async_transid, inherit); |
| } |
| if (!error) |
| fsnotify_mkdir(dir, dentry); |
| out_up_read: |
| up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem); |
| out_dput: |
| dput(dentry); |
| out_unlock: |
| mutex_unlock(&dir->i_mutex); |
| return error; |
| } |
| |
| /* |
| * When we're defragging a range, we don't want to kick it off again |
| * if it is really just waiting for delalloc to send it down. |
| * If we find a nice big extent or delalloc range for the bytes in the |
| * file you want to defrag, we return 0 to let you know to skip this |
| * part of the file |
| */ |
| static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh) |
| { |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| struct extent_map *em = NULL; |
| struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
| u64 end; |
| |
| read_lock(&em_tree->lock); |
| em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); |
| read_unlock(&em_tree->lock); |
| |
| if (em) { |
| end = extent_map_end(em); |
| free_extent_map(em); |
| if (end - offset > thresh) |
| return 0; |
| } |
| /* if we already have a nice delalloc here, just stop */ |
| thresh /= 2; |
| end = count_range_bits(io_tree, &offset, offset + thresh, |
| thresh, EXTENT_DELALLOC, 1); |
| if (end >= thresh) |
| return 0; |
| return 1; |
| } |
| |
| /* |
| * helper function to walk through a file and find extents |
| * newer than a specific transid, and smaller than thresh. |
| * |
| * This is used by the defragging code to find new and small |
| * extents |
| */ |
| static int find_new_extents(struct btrfs_root *root, |
| struct inode *inode, u64 newer_than, |
| u64 *off, int thresh) |
| { |
| struct btrfs_path *path; |
| struct btrfs_key min_key; |
| struct btrfs_key max_key; |
| struct extent_buffer *leaf; |
| struct btrfs_file_extent_item *extent; |
| int type; |
| int ret; |
| u64 ino = btrfs_ino(inode); |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| min_key.objectid = ino; |
| min_key.type = BTRFS_EXTENT_DATA_KEY; |
| min_key.offset = *off; |
| |
| max_key.objectid = ino; |
| max_key.type = (u8)-1; |
| max_key.offset = (u64)-1; |
| |
| path->keep_locks = 1; |
| |
| while(1) { |
| ret = btrfs_search_forward(root, &min_key, &max_key, |
| path, 0, newer_than); |
| if (ret != 0) |
| goto none; |
| if (min_key.objectid != ino) |
| goto none; |
| if (min_key.type != BTRFS_EXTENT_DATA_KEY) |
| goto none; |
| |
| leaf = path->nodes[0]; |
| extent = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| |
| type = btrfs_file_extent_type(leaf, extent); |
| if (type == BTRFS_FILE_EXTENT_REG && |
| btrfs_file_extent_num_bytes(leaf, extent) < thresh && |
| check_defrag_in_cache(inode, min_key.offset, thresh)) { |
| *off = min_key.offset; |
| btrfs_free_path(path); |
| return 0; |
| } |
| |
| if (min_key.offset == (u64)-1) |
| goto none; |
| |
| min_key.offset++; |
| btrfs_release_path(path); |
| } |
| none: |
| btrfs_free_path(path); |
| return -ENOENT; |
| } |
| |
| static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start) |
| { |
| struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| struct extent_map *em; |
| u64 len = PAGE_CACHE_SIZE; |
| |
| /* |
| * hopefully we have this extent in the tree already, try without |
| * the full extent lock |
| */ |
| read_lock(&em_tree->lock); |
| em = lookup_extent_mapping(em_tree, start, len); |
| read_unlock(&em_tree->lock); |
| |
| if (!em) { |
| /* get the big lock and read metadata off disk */ |
| lock_extent(io_tree, start, start + len - 1); |
| em = btrfs_get_extent(inode, NULL, 0, start, len, 0); |
| unlock_extent(io_tree, start, start + len - 1); |
| |
| if (IS_ERR(em)) |
| return NULL; |
| } |
| |
| return em; |
| } |
| |
| static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) |
| { |
| struct extent_map *next; |
| bool ret = true; |
| |
| /* this is the last extent */ |
| if (em->start + em->len >= i_size_read(inode)) |
| return false; |
| |
| next = defrag_lookup_extent(inode, em->start + em->len); |
| if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) |
| ret = false; |
| |
| free_extent_map(next); |
| return ret; |
| } |
| |
| static int should_defrag_range(struct inode *inode, u64 start, int thresh, |
| u64 *last_len, u64 *skip, u64 *defrag_end, |
| int compress) |
| { |
| struct extent_map *em; |
| int ret = 1; |
| bool next_mergeable = true; |
| |
| /* |
| * make sure that once we start defragging an extent, we keep on |
| * defragging it |
| */ |
| if (start < *defrag_end) |
| return 1; |
| |
| *skip = 0; |
| |
| em = defrag_lookup_extent(inode, start); |
| if (!em) |
| return 0; |
| |
| /* this will cover holes, and inline extents */ |
| if (em->block_start >= EXTENT_MAP_LAST_BYTE) { |
| ret = 0; |
| goto out; |
| } |
| |
| next_mergeable = defrag_check_next_extent(inode, em); |
| |
| /* |
| * we hit a real extent, if it is big or the next extent is not a |
| * real extent, don't bother defragging it |
| */ |
| if (!compress && (*last_len == 0 || *last_len >= thresh) && |
| (em->len >= thresh || !next_mergeable)) |
| ret = 0; |
| out: |
| /* |
| * last_len ends up being a counter of how many bytes we've defragged. |
| * every time we choose not to defrag an extent, we reset *last_len |
| * so that the next tiny extent will force a defrag. |
| * |
| * The end result of this is that tiny extents before a single big |
| * extent will force at least part of that big extent to be defragged. |
| */ |
| if (ret) { |
| *defrag_end = extent_map_end(em); |
| } else { |
| *last_len = 0; |
| *skip = extent_map_end(em); |
| *defrag_end = 0; |
| } |
| |
| free_extent_map(em); |
| return ret; |
| } |
| |
| /* |
| * it doesn't do much good to defrag one or two pages |
| * at a time. This pulls in a nice chunk of pages |
| * to COW and defrag. |
| * |
| * It also makes sure the delalloc code has enough |
| * dirty data to avoid making new small extents as part |
| * of the defrag |
| * |
| * It's a good idea to start RA on this range |
| * before calling this. |
| */ |
| static int cluster_pages_for_defrag(struct inode *inode, |
| struct page **pages, |
| unsigned long start_index, |
| int num_pages) |
| { |
| unsigned long file_end; |
| u64 isize = i_size_read(inode); |
| u64 page_start; |
| u64 page_end; |
| u64 page_cnt; |
| int ret; |
| int i; |
| int i_done; |
| struct btrfs_ordered_extent *ordered; |
| struct extent_state *cached_state = NULL; |
| struct extent_io_tree *tree; |
| gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); |
| |
| file_end = (isize - 1) >> PAGE_CACHE_SHIFT; |
| if (!isize || start_index > file_end) |
| return 0; |
| |
| page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); |
| |
| ret = btrfs_delalloc_reserve_space(inode, |
| page_cnt << PAGE_CACHE_SHIFT); |
| if (ret) |
| return ret; |
| i_done = 0; |
| tree = &BTRFS_I(inode)->io_tree; |
| |
| /* step one, lock all the pages */ |
| for (i = 0; i < page_cnt; i++) { |
| struct page *page; |
| again: |
| page = find_or_create_page(inode->i_mapping, |
| start_index + i, mask); |
| if (!page) |
| break; |
| |
| page_start = page_offset(page); |
| page_end = page_start + PAGE_CACHE_SIZE - 1; |
| while (1) { |
| lock_extent(tree, page_start, page_end); |
| ordered = btrfs_lookup_ordered_extent(inode, |
| page_start); |
| unlock_extent(tree, page_start, page_end); |
| if (!ordered) |
| break; |
| |
| unlock_page(page); |
| btrfs_start_ordered_extent(inode, ordered, 1); |
| btrfs_put_ordered_extent(ordered); |
| lock_page(page); |
| /* |
| * we unlocked the page above, so we need check if |
| * it was released or not. |
| */ |
| if (page->mapping != inode->i_mapping) { |
| unlock_page(page); |
| page_cache_release(page); |
| goto again; |
| } |
| } |
| |
| if (!PageUptodate(page)) { |
| btrfs_readpage(NULL, page); |
| lock_page(page); |
| if (!PageUptodate(page)) { |
| unlock_page(page); |
| page_cache_release(page); |
| ret = -EIO; |
| break; |
| } |
| } |
| |
| if (page->mapping != inode->i_mapping) { |
| unlock_page(page); |
| page_cache_release(page); |
| goto again; |
| } |
| |
| pages[i] = page; |
| i_done++; |
| } |
| if (!i_done || ret) |
| goto out; |
| |
| if (!(inode->i_sb->s_flags & MS_ACTIVE)) |
| goto out; |
| |
| /* |
| * so now we have a nice long stream of locked |
| * and up to date pages, lets wait on them |
| */ |
| for (i = 0; i < i_done; i++) |
| wait_on_page_writeback(pages[i]); |
| |
| page_start = page_offset(pages[0]); |
| page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE; |
| |
| lock_extent_bits(&BTRFS_I(inode)->io_tree, |
| page_start, page_end - 1, 0, &cached_state); |
| clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, |
| page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | |
| EXTENT_DO_ACCOUNTING, 0, 0, &cached_state, |
| GFP_NOFS); |
| |
| if (i_done != page_cnt) { |
| spin_lock(&BTRFS_I(inode)->lock); |
| BTRFS_I(inode)->outstanding_extents++; |
| spin_unlock(&BTRFS_I(inode)->lock); |
| btrfs_delalloc_release_space(inode, |
| (page_cnt - i_done) << PAGE_CACHE_SHIFT); |
| } |
| |
| |
| btrfs_set_extent_delalloc(inode, page_start, page_end - 1, |
| &cached_state); |
| |
| unlock_extent_cached(&BTRFS_I(inode)->io_tree, |
| page_start, page_end - 1, &cached_state, |
| GFP_NOFS); |
| |
| for (i = 0; i < i_done; i++) { |
| clear_page_dirty_for_io(pages[i]); |
| ClearPageChecked(pages[i]); |
| set_page_extent_mapped(pages[i]); |
| set_page_dirty(pages[i]); |
| unlock_page(pages[i]); |
| page_cache_release(pages[i]); |
| } |
| return i_done; |
| out: |
| for (i = 0; i < i_done; i++) { |
| unlock_page(pages[i]); |
| page_cache_release(pages[i]); |
| } |
| btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT); |
| return ret; |
| |
| } |
| |
| int btrfs_defrag_file(struct inode *inode, struct file *file, |
| struct btrfs_ioctl_defrag_range_args *range, |
| u64 newer_than, unsigned long max_to_defrag) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct file_ra_state *ra = NULL; |
| unsigned long last_index; |
| u64 isize = i_size_read(inode); |
| u64 last_len = 0; |
| u64 skip = 0; |
| u64 defrag_end = 0; |
| u64 newer_off = range->start; |
| unsigned long i; |
| unsigned long ra_index = 0; |
| int ret; |
| int defrag_count = 0; |
| int compress_type = BTRFS_COMPRESS_ZLIB; |
| int extent_thresh = range->extent_thresh; |
| int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT; |
| int cluster = max_cluster; |
| u64 new_align = ~((u64)128 * 1024 - 1); |
| struct page **pages = NULL; |
| |
| if (extent_thresh == 0) |
| extent_thresh = 256 * 1024; |
| |
| if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) { |
| if (range->compress_type > BTRFS_COMPRESS_TYPES) |
| return -EINVAL; |
| if (range->compress_type) |
| compress_type = range->compress_type; |
| } |
| |
| if (isize == 0) |
| return 0; |
| |
| /* |
| * if we were not given a file, allocate a readahead |
| * context |
| */ |
| if (!file) { |
| ra = kzalloc(sizeof(*ra), GFP_NOFS); |
| if (!ra) |
| return -ENOMEM; |
| file_ra_state_init(ra, inode->i_mapping); |
| } else { |
| ra = &file->f_ra; |
| } |
| |
| pages = kmalloc(sizeof(struct page *) * max_cluster, |
| GFP_NOFS); |
| if (!pages) { |
| ret = -ENOMEM; |
| goto out_ra; |
| } |
| |
| /* find the last page to defrag */ |
| if (range->start + range->len > range->start) { |
| last_index = min_t(u64, isize - 1, |
| range->start + range->len - 1) >> PAGE_CACHE_SHIFT; |
| } else { |
| last_index = (isize - 1) >> PAGE_CACHE_SHIFT; |
| } |
| |
| if (newer_than) { |
| ret = find_new_extents(root, inode, newer_than, |
| &newer_off, 64 * 1024); |
| if (!ret) { |
| range->start = newer_off; |
| /* |
| * we always align our defrag to help keep |
| * the extents in the file evenly spaced |
| */ |
| i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; |
| } else |
| goto out_ra; |
| } else { |
| i = range->start >> PAGE_CACHE_SHIFT; |
| } |
| if (!max_to_defrag) |
| max_to_defrag = last_index + 1; |
| |
| /* |
| * make writeback starts from i, so the defrag range can be |
| * written sequentially. |
| */ |
| if (i < inode->i_mapping->writeback_index) |
| inode->i_mapping->writeback_index = i; |
| |
| while (i <= last_index && defrag_count < max_to_defrag && |
| (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> |
| PAGE_CACHE_SHIFT)) { |
| /* |
| * make sure we stop running if someone unmounts |
| * the FS |
| */ |
| if (!(inode->i_sb->s_flags & MS_ACTIVE)) |
| break; |
| |
| if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT, |
| extent_thresh, &last_len, &skip, |
| &defrag_end, range->flags & |
| BTRFS_DEFRAG_RANGE_COMPRESS)) { |
| unsigned long next; |
| /* |
| * the should_defrag function tells us how much to skip |
| * bump our counter by the suggested amount |
| */ |
| next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; |
| i = max(i + 1, next); |
| continue; |
| } |
| |
| if (!newer_than) { |
| cluster = (PAGE_CACHE_ALIGN(defrag_end) >> |
| PAGE_CACHE_SHIFT) - i; |
| cluster = min(cluster, max_cluster); |
| } else { |
| cluster = max_cluster; |
| } |
| |
| if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) |
| BTRFS_I(inode)->force_compress = compress_type; |
| |
| if (i + cluster > ra_index) { |
| ra_index = max(i, ra_index); |
| btrfs_force_ra(inode->i_mapping, ra, file, ra_index, |
| cluster); |
| ra_index += max_cluster; |
| } |
| |
| mutex_lock(&inode->i_mutex); |
| ret = cluster_pages_for_defrag(inode, pages, i, cluster); |
| if (ret < 0) { |
| mutex_unlock(&inode->i_mutex); |
| goto out_ra; |
| } |
| |
| defrag_count += ret; |
| balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret); |
| mutex_unlock(&inode->i_mutex); |
| |
| if (newer_than) { |
| if (newer_off == (u64)-1) |
| break; |
| |
| if (ret > 0) |
| i += ret; |
| |
| newer_off = max(newer_off + 1, |
| (u64)i << PAGE_CACHE_SHIFT); |
| |
| ret = find_new_extents(root, inode, |
| newer_than, &newer_off, |
| 64 * 1024); |
| if (!ret) { |
| range->start = newer_off; |
| i = (newer_off & new_align) >> PAGE_CACHE_SHIFT; |
| } else { |
| break; |
| } |
| } else { |
| if (ret > 0) { |
| i += ret; |
| last_len += ret << PAGE_CACHE_SHIFT; |
| } else { |
| i++; |
| last_len = 0; |
| } |
| } |
| } |
| |
| if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) |
| filemap_flush(inode->i_mapping); |
| |
| if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { |
| /* the filemap_flush will queue IO into the worker threads, but |
| * we have to make sure the IO is actually started and that |
| * ordered extents get created before we return |
| */ |
| atomic_inc(&root->fs_info->async_submit_draining); |
| while (atomic_read(&root->fs_info->nr_async_submits) || |
| atomic_read(&root->fs_info->async_delalloc_pages)) { |
| wait_event(root->fs_info->async_submit_wait, |
| (atomic_read(&root->fs_info->nr_async_submits) == 0 && |
| atomic_read(&root->fs_info->async_delalloc_pages) == 0)); |
| } |
| atomic_dec(&root->fs_info->async_submit_draining); |
| |
| mutex_lock(&inode->i_mutex); |
| BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE; |
| mutex_unlock(&inode->i_mutex); |
| } |
| |
| if (range->compress_type == BTRFS_COMPRESS_LZO) { |
| btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO); |
| } |
| |
| ret = defrag_count; |
| |
| out_ra: |
| if (!file) |
| kfree(ra); |
| kfree(pages); |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_resize(struct btrfs_root *root, |
| void __user *arg) |
| { |
| u64 new_size; |
| u64 old_size; |
| u64 devid = 1; |
| struct btrfs_ioctl_vol_args *vol_args; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_device *device = NULL; |
| char *sizestr; |
| char *devstr = NULL; |
| int ret = 0; |
| int mod = 0; |
| |
| if (root->fs_info->sb->s_flags & MS_RDONLY) |
| return -EROFS; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| mutex_lock(&root->fs_info->volume_mutex); |
| if (root->fs_info->balance_ctl) { |
| printk(KERN_INFO "btrfs: balance in progress\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| vol_args = memdup_user(arg, sizeof(*vol_args)); |
| if (IS_ERR(vol_args)) { |
| ret = PTR_ERR(vol_args); |
| goto out; |
| } |
| |
| vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; |
| |
| sizestr = vol_args->name; |
| devstr = strchr(sizestr, ':'); |
| if (devstr) { |
| char *end; |
| sizestr = devstr + 1; |
| *devstr = '\0'; |
| devstr = vol_args->name; |
| devid = simple_strtoull(devstr, &end, 10); |
| printk(KERN_INFO "btrfs: resizing devid %llu\n", |
| (unsigned long long)devid); |
| } |
| device = btrfs_find_device(root, devid, NULL, NULL); |
| if (!device) { |
| printk(KERN_INFO "btrfs: resizer unable to find device %llu\n", |
| (unsigned long long)devid); |
| ret = -EINVAL; |
| goto out_free; |
| } |
| if (device->fs_devices && device->fs_devices->seeding) { |
| printk(KERN_INFO "btrfs: resizer unable to apply on " |
| "seeding device %llu\n", |
| (unsigned long long)devid); |
| ret = -EINVAL; |
| goto out_free; |
| } |
| |
| if (!strcmp(sizestr, "max")) |
| new_size = device->bdev->bd_inode->i_size; |
| else { |
| if (sizestr[0] == '-') { |
| mod = -1; |
| sizestr++; |
| } else if (sizestr[0] == '+') { |
| mod = 1; |
| sizestr++; |
| } |
| new_size = memparse(sizestr, NULL); |
| if (new_size == 0) { |
| ret = -EINVAL; |
| goto out_free; |
| } |
| } |
| |
| old_size = device->total_bytes; |
| |
| if (mod < 0) { |
| if (new_size > old_size) { |
| ret = -EINVAL; |
| goto out_free; |
| } |
| new_size = old_size - new_size; |
| } else if (mod > 0) { |
| new_size = old_size + new_size; |
| } |
| |
| if (new_size < 256 * 1024 * 1024) { |
| ret = -EINVAL; |
| goto out_free; |
| } |
| if (new_size > device->bdev->bd_inode->i_size) { |
| ret = -EFBIG; |
| goto out_free; |
| } |
| |
| do_div(new_size, root->sectorsize); |
| new_size *= root->sectorsize; |
| |
| printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n", |
| rcu_str_deref(device->name), |
| (unsigned long long)new_size); |
| |
| if (new_size > old_size) { |
| trans = btrfs_start_transaction(root, 0); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| goto out_free; |
| } |
| ret = btrfs_grow_device(trans, device, new_size); |
| btrfs_commit_transaction(trans, root); |
| } else if (new_size < old_size) { |
| ret = btrfs_shrink_device(device, new_size); |
| } |
| |
| out_free: |
| kfree(vol_args); |
| out: |
| mutex_unlock(&root->fs_info->volume_mutex); |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_snap_create_transid(struct file *file, |
| char *name, unsigned long fd, int subvol, |
| u64 *transid, bool readonly, |
| struct btrfs_qgroup_inherit **inherit) |
| { |
| struct file *src_file; |
| int namelen; |
| int ret = 0; |
| |
| ret = mnt_want_write_file(file); |
| if (ret) |
| goto out; |
| |
| namelen = strlen(name); |
| if (strchr(name, '/')) { |
| ret = -EINVAL; |
| goto out_drop_write; |
| } |
| |
| if (name[0] == '.' && |
| (namelen == 1 || (name[1] == '.' && namelen == 2))) { |
| ret = -EEXIST; |
| goto out_drop_write; |
| } |
| |
| if (subvol) { |
| ret = btrfs_mksubvol(&file->f_path, name, namelen, |
| NULL, transid, readonly, inherit); |
| } else { |
| struct inode *src_inode; |
| src_file = fget(fd); |
| if (!src_file) { |
| ret = -EINVAL; |
| goto out_drop_write; |
| } |
| |
| src_inode = src_file->f_path.dentry->d_inode; |
| if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { |
| printk(KERN_INFO "btrfs: Snapshot src from " |
| "another FS\n"); |
| ret = -EINVAL; |
| fput(src_file); |
| goto out_drop_write; |
| } |
| ret = btrfs_mksubvol(&file->f_path, name, namelen, |
| BTRFS_I(src_inode)->root, |
| transid, readonly, inherit); |
| fput(src_file); |
| } |
| out_drop_write: |
| mnt_drop_write_file(file); |
| out: |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_snap_create(struct file *file, |
| void __user *arg, int subvol) |
| { |
| struct btrfs_ioctl_vol_args *vol_args; |
| int ret; |
| |
| vol_args = memdup_user(arg, sizeof(*vol_args)); |
| if (IS_ERR(vol_args)) |
| return PTR_ERR(vol_args); |
| vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; |
| |
| ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, |
| vol_args->fd, subvol, |
| NULL, false, NULL); |
| |
| kfree(vol_args); |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_snap_create_v2(struct file *file, |
| void __user *arg, int subvol) |
| { |
| struct btrfs_ioctl_vol_args_v2 *vol_args; |
| int ret; |
| u64 transid = 0; |
| u64 *ptr = NULL; |
| bool readonly = false; |
| struct btrfs_qgroup_inherit *inherit = NULL; |
| |
| vol_args = memdup_user(arg, sizeof(*vol_args)); |
| if (IS_ERR(vol_args)) |
| return PTR_ERR(vol_args); |
| vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; |
| |
| if (vol_args->flags & |
| ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | |
| BTRFS_SUBVOL_QGROUP_INHERIT)) { |
| ret = -EOPNOTSUPP; |
| goto out; |
| } |
| |
| if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) |
| ptr = &transid; |
| if (vol_args->flags & BTRFS_SUBVOL_RDONLY) |
| readonly = true; |
| if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { |
| if (vol_args->size > PAGE_CACHE_SIZE) { |
| ret = -EINVAL; |
| goto out; |
| } |
| inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); |
| if (IS_ERR(inherit)) { |
| ret = PTR_ERR(inherit); |
| goto out; |
| } |
| } |
| |
| ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, |
| vol_args->fd, subvol, ptr, |
| readonly, &inherit); |
| |
| if (ret == 0 && ptr && |
| copy_to_user(arg + |
| offsetof(struct btrfs_ioctl_vol_args_v2, |
| transid), ptr, sizeof(*ptr))) |
| ret = -EFAULT; |
| out: |
| kfree(vol_args); |
| kfree(inherit); |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_subvol_getflags(struct file *file, |
| void __user *arg) |
| { |
| struct inode *inode = fdentry(file)->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| int ret = 0; |
| u64 flags = 0; |
| |
| if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) |
| return -EINVAL; |
| |
| down_read(&root->fs_info->subvol_sem); |
| if (btrfs_root_readonly(root)) |
| flags |= BTRFS_SUBVOL_RDONLY; |
| up_read(&root->fs_info->subvol_sem); |
| |
| if (copy_to_user(arg, &flags, sizeof(flags))) |
| ret = -EFAULT; |
| |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_subvol_setflags(struct file *file, |
| void __user *arg) |
| { |
| struct inode *inode = fdentry(file)->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| u64 root_flags; |
| u64 flags; |
| int ret = 0; |
| |
| ret = mnt_want_write_file(file); |
| if (ret) |
| goto out; |
| |
| if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { |
| ret = -EINVAL; |
| goto out_drop_write; |
| } |
| |
| if (copy_from_user(&flags, arg, sizeof(flags))) { |
| ret = -EFAULT; |
| goto out_drop_write; |
| } |
| |
| if (flags & BTRFS_SUBVOL_CREATE_ASYNC) { |
| ret = -EINVAL; |
| goto out_drop_write; |
| } |
| |
| if (flags & ~BTRFS_SUBVOL_RDONLY) { |
| ret = -EOPNOTSUPP; |
| goto out_drop_write; |
| } |
| |
| if (!inode_owner_or_capable(inode)) { |
| ret = -EACCES; |
| goto out_drop_write; |
| } |
| |
| down_write(&root->fs_info->subvol_sem); |
| |
| /* nothing to do */ |
| if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) |
| goto out_drop_sem; |
| |
| root_flags = btrfs_root_flags(&root->root_item); |
| if (flags & BTRFS_SUBVOL_RDONLY) |
| btrfs_set_root_flags(&root->root_item, |
| root_flags | BTRFS_ROOT_SUBVOL_RDONLY); |
| else |
| btrfs_set_root_flags(&root->root_item, |
| root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); |
| |
| trans = btrfs_start_transaction(root, 1); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| goto out_reset; |
| } |
| |
| ret = btrfs_update_root(trans, root->fs_info->tree_root, |
| &root->root_key, &root->root_item); |
| |
| btrfs_commit_transaction(trans, root); |
| out_reset: |
| if (ret) |
| btrfs_set_root_flags(&root->root_item, root_flags); |
| out_drop_sem: |
| up_write(&root->fs_info->subvol_sem); |
| out_drop_write: |
| mnt_drop_write_file(file); |
| out: |
| return ret; |
| } |
| |
| /* |
| * helper to check if the subvolume references other subvolumes |
| */ |
| static noinline int may_destroy_subvol(struct btrfs_root *root) |
| { |
| struct btrfs_path *path; |
| struct btrfs_key key; |
| int ret; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| key.objectid = root->root_key.objectid; |
| key.type = BTRFS_ROOT_REF_KEY; |
| key.offset = (u64)-1; |
| |
| ret = btrfs_search_slot(NULL, root->fs_info->tree_root, |
| &key, path, 0, 0); |
| if (ret < 0) |
| goto out; |
| BUG_ON(ret == 0); |
| |
| ret = 0; |
| if (path->slots[0] > 0) { |
| path->slots[0]--; |
| btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); |
| if (key.objectid == root->root_key.objectid && |
| key.type == BTRFS_ROOT_REF_KEY) |
| ret = -ENOTEMPTY; |
| } |
| out: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| static noinline int key_in_sk(struct btrfs_key *key, |
| struct btrfs_ioctl_search_key *sk) |
| { |
| struct btrfs_key test; |
| int ret; |
| |
| test.objectid = sk->min_objectid; |
| test.type = sk->min_type; |
| test.offset = sk->min_offset; |
| |
| ret = btrfs_comp_cpu_keys(key, &test); |
| if (ret < 0) |
| return 0; |
| |
| test.objectid = sk->max_objectid; |
| test.type = sk->max_type; |
| test.offset = sk->max_offset; |
| |
| ret = btrfs_comp_cpu_keys(key, &test); |
| if (ret > 0) |
| return 0; |
| return 1; |
| } |
| |
| static noinline int copy_to_sk(struct btrfs_root *root, |
| struct btrfs_path *path, |
| struct btrfs_key *key, |
| struct btrfs_ioctl_search_key *sk, |
| char *buf, |
| unsigned long *sk_offset, |
| int *num_found) |
| { |
| u64 found_transid; |
| struct extent_buffer *leaf; |
| struct btrfs_ioctl_search_header sh; |
| unsigned long item_off; |
| unsigned long item_len; |
| int nritems; |
| int i; |
| int slot; |
| int ret = 0; |
| |
| leaf = path->nodes[0]; |
| slot = path->slots[0]; |
| nritems = btrfs_header_nritems(leaf); |
| |
| if (btrfs_header_generation(leaf) > sk->max_transid) { |
| i = nritems; |
| goto advance_key; |
| } |
| found_transid = btrfs_header_generation(leaf); |
| |
| for (i = slot; i < nritems; i++) { |
| item_off = btrfs_item_ptr_offset(leaf, i); |
| item_len = btrfs_item_size_nr(leaf, i); |
| |
| if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE) |
| item_len = 0; |
| |
| if (sizeof(sh) + item_len + *sk_offset > |
| BTRFS_SEARCH_ARGS_BUFSIZE) { |
| ret = 1; |
| goto overflow; |
| } |
| |
| btrfs_item_key_to_cpu(leaf, key, i); |
| if (!key_in_sk(key, sk)) |
| continue; |
| |
| sh.objectid = key->objectid; |
| sh.offset = key->offset; |
| sh.type = key->type; |
| sh.len = item_len; |
| sh.transid = found_transid; |
| |
| /* copy search result header */ |
| memcpy(buf + *sk_offset, &sh, sizeof(sh)); |
| *sk_offset += sizeof(sh); |
| |
| if (item_len) { |
| char *p = buf + *sk_offset; |
| /* copy the item */ |
| read_extent_buffer(leaf, p, |
| item_off, item_len); |
| *sk_offset += item_len; |
| } |
| (*num_found)++; |
| |
| if (*num_found >= sk->nr_items) |
| break; |
| } |
| advance_key: |
| ret = 0; |
| if (key->offset < (u64)-1 && key->offset < sk->max_offset) |
| key->offset++; |
| else if (key->type < (u8)-1 && key->type < sk->max_type) { |
| key->offset = 0; |
| key->type++; |
| } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) { |
| key->offset = 0; |
| key->type = 0; |
| key->objectid++; |
| } else |
| ret = 1; |
| overflow: |
| return ret; |
| } |
| |
| static noinline int search_ioctl(struct inode *inode, |
| struct btrfs_ioctl_search_args *args) |
| { |
| struct btrfs_root *root; |
| struct btrfs_key key; |
| struct btrfs_key max_key; |
| struct btrfs_path *path; |
| struct btrfs_ioctl_search_key *sk = &args->key; |
| struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info; |
| int ret; |
| int num_found = 0; |
| unsigned long sk_offset = 0; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| if (sk->tree_id == 0) { |
| /* search the root of the inode that was passed */ |
| root = BTRFS_I(inode)->root; |
| } else { |
| key.objectid = sk->tree_id; |
| key.type = BTRFS_ROOT_ITEM_KEY; |
| key.offset = (u64)-1; |
| root = btrfs_read_fs_root_no_name(info, &key); |
| if (IS_ERR(root)) { |
| printk(KERN_ERR "could not find root %llu\n", |
| sk->tree_id); |
| btrfs_free_path(path); |
| return -ENOENT; |
| } |
| } |
| |
| key.objectid = sk->min_objectid; |
| key.type = sk->min_type; |
| key.offset = sk->min_offset; |
| |
| max_key.objectid = sk->max_objectid; |
| max_key.type = sk->max_type; |
| max_key.offset = sk->max_offset; |
| |
| path->keep_locks = 1; |
| |
| while(1) { |
| ret = btrfs_search_forward(root, &key, &max_key, path, 0, |
| sk->min_transid); |
| if (ret != 0) { |
| if (ret > 0) |
| ret = 0; |
| goto err; |
| } |
| ret = copy_to_sk(root, path, &key, sk, args->buf, |
| &sk_offset, &num_found); |
| btrfs_release_path(path); |
| if (ret || num_found >= sk->nr_items) |
| break; |
| |
| } |
| ret = 0; |
| err: |
| sk->nr_items = num_found; |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_tree_search(struct file *file, |
| void __user *argp) |
| { |
| struct btrfs_ioctl_search_args *args; |
| struct inode *inode; |
| int ret; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| args = memdup_user(argp, sizeof(*args)); |
| if (IS_ERR(args)) |
| return PTR_ERR(args); |
| |
| inode = fdentry(file)->d_inode; |
| ret = search_ioctl(inode, args); |
| if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) |
| ret = -EFAULT; |
| kfree(args); |
| return ret; |
| } |
| |
| /* |
| * Search INODE_REFs to identify path name of 'dirid' directory |
| * in a 'tree_id' tree. and sets path name to 'name'. |
| */ |
| static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, |
| u64 tree_id, u64 dirid, char *name) |
| { |
| struct btrfs_root *root; |
| struct btrfs_key key; |
| char *ptr; |
| int ret = -1; |
| int slot; |
| int len; |
| int total_len = 0; |
| struct btrfs_inode_ref *iref; |
| struct extent_buffer *l; |
| struct btrfs_path *path; |
| |
| if (dirid == BTRFS_FIRST_FREE_OBJECTID) { |
| name[0]='\0'; |
| return 0; |
| } |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX]; |
| |
| key.objectid = tree_id; |
| key.type = BTRFS_ROOT_ITEM_KEY; |
| key.offset = (u64)-1; |
| root = btrfs_read_fs_root_no_name(info, &key); |
| if (IS_ERR(root)) { |
| printk(KERN_ERR "could not find root %llu\n", tree_id); |
| ret = -ENOENT; |
| goto out; |
| } |
| |
| key.objectid = dirid; |
| key.type = BTRFS_INODE_REF_KEY; |
| key.offset = (u64)-1; |
| |
| while(1) { |
| ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| if (ret < 0) |
| goto out; |
| |
| l = path->nodes[0]; |
| slot = path->slots[0]; |
| if (ret > 0 && slot > 0) |
| slot--; |
| btrfs_item_key_to_cpu(l, &key, slot); |
| |
| if (ret > 0 && (key.objectid != dirid || |
| key.type != BTRFS_INODE_REF_KEY)) { |
| ret = -ENOENT; |
| goto out; |
| } |
| |
| iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); |
| len = btrfs_inode_ref_name_len(l, iref); |
| ptr -= len + 1; |
| total_len += len + 1; |
| if (ptr < name) |
| goto out; |
| |
| *(ptr + len) = '/'; |
| read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len); |
| |
| if (key.offset == BTRFS_FIRST_FREE_OBJECTID) |
| break; |
| |
| btrfs_release_path(path); |
| key.objectid = key.offset; |
| key.offset = (u64)-1; |
| dirid = key.objectid; |
| } |
| if (ptr < name) |
| goto out; |
| memmove(name, ptr, total_len); |
| name[total_len]='\0'; |
| ret = 0; |
| out: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_ino_lookup(struct file *file, |
| void __user *argp) |
| { |
| struct btrfs_ioctl_ino_lookup_args *args; |
| struct inode *inode; |
| int ret; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| args = memdup_user(argp, sizeof(*args)); |
| if (IS_ERR(args)) |
| return PTR_ERR(args); |
| |
| inode = fdentry(file)->d_inode; |
| |
| if (args->treeid == 0) |
| args->treeid = BTRFS_I(inode)->root->root_key.objectid; |
| |
| ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, |
| args->treeid, args->objectid, |
| args->name); |
| |
| if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) |
| ret = -EFAULT; |
| |
| kfree(args); |
| return ret; |
| } |
| |
| static noinline int btrfs_ioctl_snap_destroy(struct file *file, |
| void __user *arg) |
| { |
| struct dentry *parent = fdentry(file); |
| struct dentry *dentry; |
| struct inode *dir = parent->d_inode; |
| struct inode *inode; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct btrfs_root *dest = NULL; |
| struct btrfs_ioctl_vol_args *vol_args; |
| struct btrfs_trans_handle *trans; |
| int namelen; |
| int ret; |
| int err = 0; |
| |
| vol_args = memdup_user(arg, sizeof(*vol_args)); |
| if (IS_ERR(vol_args)) |
| return PTR_ERR(vol_args); |
| |
| vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; |
| namelen = strlen(vol_args->name); |
| if (strchr(vol_args->name, '/') || |
| strncmp(vol_args->name, "..", namelen) == 0) { |
| err = -EINVAL; |
| goto out; |
| } |
| |
| err = mnt_want_write_file(file); |
| if (err) |
| goto out; |
| |
| mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); |
| dentry = lookup_one_len(vol_args->name, parent, namelen); |
| if (IS_ERR(dentry)) { |
| err = PTR_ERR(dentry); |
| goto out_unlock_dir; |
| } |
| |
| if (!dentry->d_inode) { |
| err = -ENOENT; |
| goto out_dput; |
| } |
| |
| inode = dentry->d_inode; |
| dest = BTRFS_I(inode)->root; |
| if (!capable(CAP_SYS_ADMIN)){ |
| /* |
| * Regular user. Only allow this with a special mount |
| * option, when the user has write+exec access to the |
| * subvol root, and when rmdir(2) would have been |
| * allowed. |
| * |
| * Note that this is _not_ check that the subvol is |
| * empty or doesn't contain data that we wouldn't |
| * otherwise be able to delete. |
| * |
| * Users who want to delete empty subvols should try |
| * rmdir(2). |
| */ |
| err = -EPERM; |
| if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) |
| goto out_dput; |
| |
| /* |
| * Do not allow deletion if the parent dir is the same |
| * as the dir to be deleted. That means the ioctl |
| * must be called on the dentry referencing the root |
| * of the subvol, not a random directory contained |
| * within it. |
| */ |
| err = -EINVAL; |
| if (root == dest) |
| goto out_dput; |
| |
| err = inode_permission(inode, MAY_WRITE | MAY_EXEC); |
| if (err) |
| goto out_dput; |
| |
| /* check if subvolume may be deleted by a non-root user */ |
| err = btrfs_may_delete(dir, dentry, 1); |
| if (err) |
| goto out_dput; |
| } |
| |
| if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { |
| err = -EINVAL; |
| goto out_dput; |
| } |
| |
| mutex_lock(&inode->i_mutex); |
| err = d_invalidate(dentry); |
| if (err) |
| goto out_unlock; |
| |
| down_write(&root->fs_info->subvol_sem); |
| |
| err = may_destroy_subvol(dest); |
| if (err) |
| goto out_up_write; |
| |
| trans = btrfs_start_transaction(root, 0); |
| if (IS_ERR(trans)) { |
| err = PTR_ERR(trans); |
| goto out_up_write; |
| } |
| trans->block_rsv = &root->fs_info->global_block_rsv; |
| |
| ret = btrfs_unlink_subvol(trans, root, dir, |
| dest->root_key.objectid, |
| dentry->d_name.name, |
| dentry->d_name.len); |
| if (ret) { |
| err = ret; |
| btrfs_abort_transaction(trans, root, ret); |
| goto out_end_trans; |
| } |
| |
| btrfs_record_root_in_trans(trans, dest); |
| |
| memset(&dest->root_item.drop_progress, 0, |
| sizeof(dest->root_item.drop_progress)); |
| dest->root_item.drop_level = 0; |
| btrfs_set_root_refs(&dest->root_item, 0); |
| |
| if (!xchg(&dest->orphan_item_inserted, 1)) { |
| ret = btrfs_insert_orphan_item(trans, |
| root->fs_info->tree_root, |
| dest->root_key.objectid); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| err = ret; |
| goto out_end_trans; |
| } |
| } |
| out_end_trans: |
| ret = btrfs_end_transaction(trans, root); |
| if (ret && !err) |
| err = ret; |
| inode->i_flags |= S_DEAD; |
| out_up_write: |
| up_write(&root->fs_info->subvol_sem); |
| out_unlock: |
| mutex_unlock(&inode->i_mutex); |
| if (!err) { |
| shrink_dcache_sb(root->fs_info->sb); |
| btrfs_invalidate_inodes(dest); |
| d_delete(dentry); |
| } |
| out_dput: |
| dput(dentry); |
| out_unlock_dir: |
| mutex_unlock(&dir->i_mutex); |
| mnt_drop_write_file(file); |
| out: |
| kfree(vol_args); |
| return err; |
| } |
| |
| static int btrfs_ioctl_defrag(struct file *file, void __user *argp) |
| { |
| struct inode *inode = fdentry(file)->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_ioctl_defrag_range_args *range; |
| int ret; |
| |
| if (btrfs_root_readonly(root)) |
| return -EROFS; |
| |
| ret = mnt_want_write_file(file); |
| if (ret) |
| return ret; |
| |
| switch (inode->i_mode & S_IFMT) { |
| case S_IFDIR: |
| if (!capable(CAP_SYS_ADMIN)) { |
| ret = -EPERM; |
| goto out; |
| } |
| ret = btrfs_defrag_root(root, 0); |
| if (ret) |
| goto out; |
| ret = btrfs_defrag_root(root->fs_info->extent_root, 0); |
| break; |
| case S_IFREG: |
| if (!(file->f_mode & FMODE_WRITE)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| range = kzalloc(sizeof(*range), GFP_KERNEL); |
| if (!range) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| if (argp) { |
| if (copy_from_user(range, argp, |
| sizeof(*range))) { |
| ret = -EFAULT; |
| kfree(range); |
| goto out; |
| } |
| /* compression requires us to start the IO */ |
| if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { |
| range->flags |= BTRFS_DEFRAG_RANGE_START_IO; |
| range->extent_thresh = (u32)-1; |
| } |
| } else { |
| /* the rest are all set to zero by kzalloc */ |
| range->len = (u64)-1; |
| } |
| ret = btrfs_defrag_file(fdentry(file)->d_inode, file, |
| range, 0, 0); |
| if (ret > 0) |
| ret = 0; |
| kfree(range); |
| break; |
| default: |
| ret = -EINVAL; |
| } |
| out: |
| mnt_drop_write_file(file); |
| return ret; |
| } |
| |
| static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) |
| { |
| struct btrfs_ioctl_vol_args *vol_args; |
| int ret; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| mutex_lock(&root->fs_info->volume_mutex); |
| if (root->fs_info->balance_ctl) { |
| printk(KERN_INFO "btrfs: balance in progress\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| vol_args = memdup_user(arg, sizeof(*vol_args)); |
| if (IS_ERR(vol_args)) { |
| ret = PTR_ERR(vol_args); |
| goto out; |
| } |
| |
| vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; |
| ret = btrfs_init_new_device(root, vol_args->name); |
| |
| kfree(vol_args); |
| out: |
| mutex_unlock(&root->fs_info->volume_mutex); |
| return ret; |
| } |
| |
| static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) |
| { |
| struct btrfs_ioctl_vol_args *vol_args; |
| int ret; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| if (root->fs_info->sb->s_flags & MS_RDONLY) |
| return -EROFS; |
| |
| mutex_lock(&root->fs_info->volume_mutex); |
| if (root->fs_info->balance_ctl) { |
| printk(KERN_INFO "btrfs: balance in progress\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| vol_args = memdup_user(arg, sizeof(*vol_args)); |
| if (IS_ERR(vol_args)) { |
| ret = PTR_ERR(vol_args); |
| goto out; |
| } |
| |
| vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; |
| ret = btrfs_rm_device(root, vol_args->name); |
| |
| kfree(vol_args); |
| out: |
| mutex_unlock(&root->fs_info->volume_mutex); |
| return ret; |
| } |
| |
| static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) |
| { |
| struct btrfs_ioctl_fs_info_args *fi_args; |
| struct btrfs_device *device; |
| struct btrfs_device *next; |
| struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; |
| int ret = 0; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); |
| if (!fi_args) |
| return -ENOMEM; |
| |
| fi_args->num_devices = fs_devices->num_devices; |
| memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid)); |
| |
| mutex_lock(&fs_devices->device_list_mutex); |
| list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { |
| if (device->devid > fi_args->max_id) |
| fi_args->max_id = device->devid; |
| } |
| mutex_unlock(&fs_devices->device_list_mutex); |
| |
| if (copy_to_user(arg, fi_args, sizeof(*fi_args))) |
| ret = -EFAULT; |
| |
| kfree(fi_args); |
| return ret; |
| } |
| |
| static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg) |
| { |
| struct btrfs_ioctl_dev_info_args *di_args; |
| struct btrfs_device *dev; |
| struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; |
| int ret = 0; |
| char *s_uuid = NULL; |
| char empty_uuid[BTRFS_UUID_SIZE] = {0}; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| di_args = memdup_user(arg, sizeof(*di_args)); |
| if (IS_ERR(di_args)) |
| return PTR_ERR(di_args); |
| |
| if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0) |
| s_uuid = di_args->uuid; |
| |
| mutex_lock(&fs_devices->device_list_mutex); |
| dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL); |
| mutex_unlock(&fs_devices->device_list_mutex); |
| |
| if (!dev) { |
| ret = -ENODEV; |
| goto out; |
| } |
| |
| di_args->devid = dev->devid; |
| di_args->bytes_used = dev->bytes_used; |
| di_args->total_bytes = dev->total_bytes; |
| memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); |
| if (dev->name) { |
| struct rcu_string *name; |
| |
| rcu_read_lock(); |
| name = rcu_dereference(dev->name); |
| strncpy(di_args->path, name->str, sizeof(di_args->path)); |
| rcu_read_unlock(); |
| di_args->path[sizeof(di_args->path) - 1] = 0; |
| } else { |
| di_args->path[0] = '\0'; |
| } |
| |
| out: |
| if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) |
| ret = -EFAULT; |
| |
| kfree(di_args); |
| return ret; |
| } |
| |
| static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, |
| u64 off, u64 olen, u64 destoff) |
| { |
| struct inode *inode = fdentry(file)->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct file *src_file; |
| struct inode *src; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| char *buf; |
| struct btrfs_key key; |
| u32 nritems; |
| int slot; |
| int ret; |
| u64 len = olen; |
| u64 bs = root->fs_info->sb->s_blocksize; |
| u64 hint_byte; |
| |
| /* |
| * TODO: |
| * - split compressed inline extents. annoying: we need to |
| * decompress into destination's address_space (the file offset |
| * may change, so source mapping won't do), then recompress (or |
| * otherwise reinsert) a subrange. |
| * - allow ranges within the same file to be cloned (provided |
| * they don't overlap)? |
| */ |
| |
| /* the destination must be opened for writing */ |
| if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND)) |
| return -EINVAL; |
| |
| if (btrfs_root_readonly(root)) |
| return -EROFS; |
| |
| ret = mnt_want_write_file(file); |
| if (ret) |
| return ret; |
| |
| src_file = fget(srcfd); |
| if (!src_file) { |
| ret = -EBADF; |
| goto out_drop_write; |
| } |
| |
| ret = -EXDEV; |
| if (src_file->f_path.mnt != file->f_path.mnt) |
| goto out_fput; |
| |
| src = src_file->f_dentry->d_inode; |
| |
| ret = -EINVAL; |
| if (src == inode) |
| goto out_fput; |
| |
| /* the src must be open for reading */ |
| if (!(src_file->f_mode & FMODE_READ)) |
| goto out_fput; |
| |
| /* don't make the dst file partly checksummed */ |
| if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != |
| (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) |
| goto out_fput; |
| |
| ret = -EISDIR; |
| if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) |
| goto out_fput; |
| |
| ret = -EXDEV; |
| if (src->i_sb != inode->i_sb) |
| goto out_fput; |
| |
| ret = -ENOMEM; |
| buf = vmalloc(btrfs_level_size(root, 0)); |
| if (!buf) |
| goto out_fput; |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| vfree(buf); |
| goto out_fput; |
| } |
| path->reada = 2; |
| |
| if (inode < src) { |
| mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); |
| mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD); |
| } else { |
| mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT); |
| mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD); |
| } |
| |
| /* determine range to clone */ |
| ret = -EINVAL; |
| if (off + len > src->i_size || off + len < off) |
| goto out_unlock; |
| if (len == 0) |
| olen = len = src->i_size - off; |
| /* if we extend to eof, continue to block boundary */ |
| if (off + len == src->i_size) |
| len = ALIGN(src->i_size, bs) - off; |
| |
| /* verify the end result is block aligned */ |
| if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || |
| !IS_ALIGNED(destoff, bs)) |
| goto out_unlock; |
| |
| if (destoff > inode->i_size) { |
| ret = btrfs_cont_expand(inode, inode->i_size, destoff); |
| if (ret) |
| goto out_unlock; |
| } |
| |
| /* truncate page cache pages from target inode range */ |
| truncate_inode_pages_range(&inode->i_data, destoff, |
| PAGE_CACHE_ALIGN(destoff + len) - 1); |
| |
| /* do any pending delalloc/csum calc on src, one way or |
| another, and lock file content */ |
| while (1) { |
| struct btrfs_ordered_extent *ordered; |
| lock_extent(&BTRFS_I(src)->io_tree, off, off+len); |
| ordered = btrfs_lookup_first_ordered_extent(src, off+len); |
| if (!ordered && |
| !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len, |
| EXTENT_DELALLOC, 0, NULL)) |
| break; |
| unlock_extent(&BTRFS_I(src)->io_tree, off, off+len); |
| if (ordered) |
| btrfs_put_ordered_extent(ordered); |
| btrfs_wait_ordered_range(src, off, len); |
| } |
| |
| /* clone data */ |
| key.objectid = btrfs_ino(src); |
| key.type = BTRFS_EXTENT_DATA_KEY; |
| key.offset = 0; |
| |
| while (1) { |
| /* |
| * note the key will change type as we walk through the |
| * tree. |
| */ |
| ret = btrfs_search_slot(NULL, BTRFS_I(src)->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(BTRFS_I(src)->root, path); |
| if (ret < 0) |
| goto out; |
| if (ret > 0) |
| break; |
| nritems = btrfs_header_nritems(path->nodes[0]); |
| } |
| leaf = path->nodes[0]; |
| slot = path->slots[0]; |
| |
| btrfs_item_key_to_cpu(leaf, &key, slot); |
| if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || |
| key.objectid != btrfs_ino(src)) |
| break; |
| |
| if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { |
| struct btrfs_file_extent_item *extent; |
| int type; |
| u32 size; |
| struct btrfs_key new_key; |
| u64 disko = 0, diskl = 0; |
| u64 datao = 0, datal = 0; |
| u8 comp; |
| u64 endoff; |
| |
| size = btrfs_item_size_nr(leaf, slot); |
| read_extent_buffer(leaf, buf, |
| btrfs_item_ptr_offset(leaf, slot), |
| size); |
| |
| extent = btrfs_item_ptr(leaf, slot, |
| struct btrfs_file_extent_item); |
| comp = btrfs_file_extent_compression(leaf, extent); |
| type = btrfs_file_extent_type(leaf, extent); |
| if (type == BTRFS_FILE_EXTENT_REG || |
| type == BTRFS_FILE_EXTENT_PREALLOC) { |
| disko = btrfs_file_extent_disk_bytenr(leaf, |
| extent); |
| diskl = btrfs_file_extent_disk_num_bytes(leaf, |
| extent); |
| datao = btrfs_file_extent_offset(leaf, extent); |
| datal = btrfs_file_extent_num_bytes(leaf, |
| extent); |
| } else if (type == BTRFS_FILE_EXTENT_INLINE) { |
| /* take upper bound, may be compressed */ |
| datal = btrfs_file_extent_ram_bytes(leaf, |
| extent); |
| } |
| btrfs_release_path(path); |
| |
| if (key.offset + datal <= off || |
| key.offset >= off+len) |
| goto next; |
| |
| memcpy(&new_key, &key, sizeof(new_key)); |
| new_key.objectid = btrfs_ino(inode); |
| if (off <= key.offset) |
| new_key.offset = key.offset + destoff - off; |
| else |
| new_key.offset = destoff; |
| |
| /* |
| * 1 - adjusting old extent (we may have to split it) |
| * 1 - add new extent |
| * 1 - inode update |
| */ |
| trans = btrfs_start_transaction(root, 3); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| goto out; |
| } |
| |
| if (type == BTRFS_FILE_EXTENT_REG || |
| type == BTRFS_FILE_EXTENT_PREALLOC) { |
| /* |
| * a | --- range to clone ---| b |
| * | ------------- extent ------------- | |
| */ |
| |
| /* substract range b */ |
| if (key.offset + datal > off + len) |
| datal = off + len - key.offset; |
| |
| /* substract range a */ |
| if (off > key.offset) { |
| datao += off - key.offset; |
| datal -= off - key.offset; |
| } |
| |
| ret = btrfs_drop_extents(trans, inode, |
| new_key.offset, |
| new_key.offset + datal, |
| &hint_byte, 1); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, |
| ret); |
| btrfs_end_transaction(trans, root); |
| goto out; |
| } |
| |
| ret = btrfs_insert_empty_item(trans, root, path, |
| &new_key, size); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, |
| ret); |
| btrfs_end_transaction(trans, root); |
| goto out; |
| } |
| |
| leaf = path->nodes[0]; |
| slot = path->slots[0]; |
| write_extent_buffer(leaf, buf, |
| btrfs_item_ptr_offset(leaf, slot), |
| size); |
| |
| extent = btrfs_item_ptr(leaf, slot, |
| struct btrfs_file_extent_item); |
| |
| /* disko == 0 means it's a hole */ |
| if (!disko) |
| datao = 0; |
| |
| btrfs_set_file_extent_offset(leaf, extent, |
| datao); |
| btrfs_set_file_extent_num_bytes(leaf, extent, |
| datal); |
| if (disko) { |
| inode_add_bytes(inode, datal); |
| ret = btrfs_inc_extent_ref(trans, root, |
| disko, diskl, 0, |
| root->root_key.objectid, |
| btrfs_ino(inode), |
| new_key.offset - datao, |
| 0); |
| if (ret) { |
| btrfs_abort_transaction(trans, |
| root, |
| ret); |
| btrfs_end_transaction(trans, |
| root); |
| goto out; |
| |
| } |
| } |
| } else if (type == BTRFS_FILE_EXTENT_INLINE) { |
| u64 skip = 0; |
| u64 trim = 0; |
| if (off > key.offset) { |
| skip = off - key.offset; |
| new_key.offset += skip; |
| } |
| |
| if (key.offset + datal > off+len) |
| trim = key.offset + datal - (off+len); |
| |
| if (comp && (skip || trim)) { |
| ret = -EINVAL; |
| btrfs_end_transaction(trans, root); |
| goto out; |
| } |
| size -= skip + trim; |
| datal -= skip + trim; |
| |
| ret = btrfs_drop_extents(trans, inode, |
| new_key.offset, |
| new_key.offset + datal, |
| &hint_byte, 1); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, |
| ret); |
| btrfs_end_transaction(trans, root); |
| goto out; |
| } |
| |
| ret = btrfs_insert_empty_item(trans, root, path, |
| &new_key, size); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, |
| ret); |
| btrfs_end_transaction(trans, root); |
| goto out; |
| } |
| |
| if (skip) { |
| u32 start = |
| btrfs_file_extent_calc_inline_size(0); |
| memmove(buf+start, buf+start+skip, |
| datal); |
| } |
| |
| leaf = path->nodes[0]; |
| slot = path->slots[0]; |
| write_extent_buffer(leaf, buf, |
| btrfs_item_ptr_offset(leaf, slot), |
| size); |
| inode_add_bytes(inode, datal); |
| } |
| |
| btrfs_mark_buffer_dirty(leaf); |
| btrfs_release_path(path); |
| |
| inode_inc_iversion(inode); |
| inode->i_mtime = inode->i_ctime = CURRENT_TIME; |
| |
| /* |
| * we round up to the block size at eof when |
| * determining which extents to clone above, |
| * but shouldn't round up the file size |
| */ |
| endoff = new_key.offset + datal; |
| if (endoff > destoff+olen) |
| endoff = destoff+olen; |
| if (endoff > inode->i_size) |
| btrfs_i_size_write(inode, endoff); |
| |
| ret = btrfs_update_inode(trans, root, inode); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| btrfs_end_transaction(trans, root); |
| goto out; |
| } |
| ret = btrfs_end_transaction(trans, root); |
| } |
| next: |
| btrfs_release_path(path); |
| key.offset++; |
| } |
| ret = 0; |
| out: |
| btrfs_release_path(path); |
| unlock_extent(&BTRFS_I(src)->io_tree, off, off+len); |
| out_unlock: |
| mutex_unlock(&src->i_mutex); |
| mutex_unlock(&inode->i_mutex); |
| vfree(buf); |
| btrfs_free_path(path); |
| out_fput: |
| fput(src_file); |
| out_drop_write: |
| mnt_drop_write_file(file); |
| return ret; |
| } |
| |
| static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) |
| { |
| struct btrfs_ioctl_clone_range_args args; |
| |
| if (copy_from_user(&args, argp, sizeof(args))) |
| return -EFAULT; |
| return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, |
| args.src_length, args.dest_offset); |
| } |
| |
| /* |
| * there are many ways the trans_start and trans_end ioctls can lead |
| * to deadlocks. They should only be used by applications that |
| * basically own the machine, and have a very in depth understanding |
| * of all the possible deadlocks and enospc problems. |
| */ |
| static long btrfs_ioctl_trans_start(struct file *file) |
| { |
| struct inode *inode = fdentry(file)->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| int ret; |
| |
| ret = -EPERM; |
| if (!capable(CAP_SYS_ADMIN)) |
| goto out; |
| |
| ret = -EINPROGRESS; |
| if (file->private_data) |
| goto out; |
| |
| ret = -EROFS; |
| if (btrfs_root_readonly(root)) |
| goto out; |
| |
| ret = mnt_want_write_file(file); |
| if (ret) |
| goto out; |
| |
| atomic_inc(&root->fs_info->open_ioctl_trans); |
| |
| ret = -ENOMEM; |
| trans = btrfs_start_ioctl_transaction(root); |
| if (IS_ERR(trans)) |
| goto out_drop; |
| |
| file->private_data = trans; |
| return 0; |
| |
| out_drop: |
| atomic_dec(&root->fs_info->open_ioctl_trans); |
| mnt_drop_write_file(file); |
| out: |
| return ret; |
| } |
| |
| static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) |
| { |
| struct inode *inode = fdentry(file)->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_root *new_root; |
| struct btrfs_dir_item *di; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_path *path; |
| struct btrfs_key location; |
| struct btrfs_disk_key disk_key; |
| u64 objectid = 0; |
| u64 dir_id; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| if (copy_from_user(&objectid, argp, sizeof(objectid))) |
| return -EFAULT; |
| |
| if (!objectid) |
| objectid = root->root_key.objectid; |
| |
| location.objectid = objectid; |
| location.type = BTRFS_ROOT_ITEM_KEY; |
| location.offset = (u64)-1; |
| |
| new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); |
| if (IS_ERR(new_root)) |
| return PTR_ERR(new_root); |
| |
| if (btrfs_root_refs(&new_root->root_item) == 0) |
| return -ENOENT; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| path->leave_spinning = 1; |
| |
| trans = btrfs_start_transaction(root, 1); |
| if (IS_ERR(trans)) { |
| btrfs_free_path(path); |
| return PTR_ERR(trans); |
| } |
| |
| dir_id = btrfs_super_root_dir(root->fs_info->super_copy); |
| di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path, |
| dir_id, "default", 7, 1); |
| if (IS_ERR_OR_NULL(di)) { |
| btrfs_free_path(path); |
| btrfs_end_transaction(trans, root); |
| printk(KERN_ERR "Umm, you don't have the default dir item, " |
| "this isn't going to work\n"); |
| return -ENOENT; |
| } |
| |
| btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); |
| btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); |
| btrfs_mark_buffer_dirty(path->nodes[0]); |
| btrfs_free_path(path); |
| |
| btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL); |
| btrfs_end_transaction(trans, root); |
| |
| return 0; |
| } |
| |
| static void get_block_group_info(struct list_head *groups_list, |
| struct btrfs_ioctl_space_info *space) |
| { |
| struct btrfs_block_group_cache *block_group; |
| |
| space->total_bytes = 0; |
| space->used_bytes = 0; |
| space->flags = 0; |
| list_for_each_entry(block_group, groups_list, list) { |
| space->flags = block_group->flags; |
| space->total_bytes += block_group->key.offset; |
| space->used_bytes += |
| btrfs_block_group_used(&block_group->item); |
| } |
| } |
| |
| long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) |
| { |
| struct btrfs_ioctl_space_args space_args; |
| struct btrfs_ioctl_space_info space; |
| struct btrfs_ioctl_space_info *dest; |
| struct btrfs_ioctl_space_info *dest_orig; |
| struct btrfs_ioctl_space_info __user *user_dest; |
| struct btrfs_space_info *info; |
| u64 types[] = {BTRFS_BLOCK_GROUP_DATA, |
| BTRFS_BLOCK_GROUP_SYSTEM, |
| BTRFS_BLOCK_GROUP_METADATA, |
| BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA}; |
| int num_types = 4; |
| int alloc_size; |
| int ret = 0; |
| u64 slot_count = 0; |
| int i, c; |
| |
| if (copy_from_user(&space_args, |
| (struct btrfs_ioctl_space_args __user *)arg, |
| sizeof(space_args))) |
| return -EFAULT; |
| |
| for (i = 0; i < num_types; i++) { |
| struct btrfs_space_info *tmp; |
| |
| info = NULL; |
| rcu_read_lock(); |
| list_for_each_entry_rcu(tmp, &root->fs_info->space_info, |
| list) { |
| if (tmp->flags == types[i]) { |
| info = tmp; |
| break; |
| } |
| } |
| rcu_read_unlock(); |
| |
| if (!info) |
| continue; |
| |
| down_read(&info->groups_sem); |
| for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { |
| if (!list_empty(&info->block_groups[c])) |
| slot_count++; |
| } |
| up_read(&info->groups_sem); |
| } |
| |
| /* space_slots == 0 means they are asking for a count */ |
| if (space_args.space_slots == 0) { |
| space_args.total_spaces = slot_count; |
| goto out; |
| } |
| |
| slot_count = min_t(u64, space_args.space_slots, slot_count); |
| |
| alloc_size = sizeof(*dest) * slot_count; |
| |
| /* we generally have at most 6 or so space infos, one for each raid |
| * level. So, a whole page should be more than enough for everyone |
| */ |
| if (alloc_size > PAGE_CACHE_SIZE) |
| return -ENOMEM; |
| |
| space_args.total_spaces = 0; |
| dest = kmalloc(alloc_size, GFP_NOFS); |
| if (!dest) |
| return -ENOMEM; |
| dest_orig = dest; |
| |
| /* now we have a buffer to copy into */ |
| for (i = 0; i < num_types; i++) { |
| struct btrfs_space_info *tmp; |
| |
| if (!slot_count) |
| break; |
| |
| info = NULL; |
| rcu_read_lock(); |
| list_for_each_entry_rcu(tmp, &root->fs_info->space_info, |
| list) { |
| if (tmp->flags == types[i]) { |
| info = tmp; |
| break; |
| } |
| } |
| rcu_read_unlock(); |
| |
| if (!info) |
| continue; |
| down_read(&info->groups_sem); |
| for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { |
| if (!list_empty(&info->block_groups[c])) { |
| get_block_group_info(&info->block_groups[c], |
| &space); |
| memcpy(dest, &space, sizeof(space)); |
| dest++; |
| space_args.total_spaces++; |
| slot_count--; |
| } |
| if (!slot_count) |
| break; |
| } |
| up_read(&info->groups_sem); |
| } |
| |
| user_dest = (struct btrfs_ioctl_space_info __user *) |
| (arg + sizeof(struct btrfs_ioctl_space_args)); |
| |
| if (copy_to_user(user_dest, dest_orig, alloc_size)) |
| ret = -EFAULT; |
| |
| kfree(dest_orig); |
| out: |
| if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) |
| ret = -EFAULT; |
| |
| return ret; |
| } |
| |
| /* |
| * there are many ways the trans_start and trans_end ioctls can lead |
| * to deadlocks. They should only be used by applications that |
| * basically own the machine, and have a very in depth understanding |
| * of all the possible deadlocks and enospc problems. |
| */ |
| long btrfs_ioctl_trans_end(struct file *file) |
| { |
| struct inode *inode = fdentry(file)->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| |
| trans = file->private_data; |
| if (!trans) |
| return -EINVAL; |
| file->private_data = NULL; |
| |
| btrfs_end_transaction(trans, root); |
| |
| atomic_dec(&root->fs_info->open_ioctl_trans); |
| |
| mnt_drop_write_file(file); |
| return 0; |
| } |
| |
| static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp) |
| { |
| struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root; |
| struct btrfs_trans_handle *trans; |
| u64 transid; |
| int ret; |
| |
| trans = btrfs_start_transaction(root, 0); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| transid = trans->transid; |
| ret = btrfs_commit_transaction_async(trans, root, 0); |
| if (ret) { |
| btrfs_end_transaction(trans, root); |
| return ret; |
| } |
| |
| if (argp) |
| if (copy_to_user(argp, &transid, |