zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/fs/btrfs/ioctl.c b/ap/os/linux/linux-3.4.x/fs/btrfs/ioctl.c
new file mode 100644
index 0000000..d46c481
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/btrfs/ioctl.c
@@ -0,0 +1,3435 @@
+/*
+ * 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 "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"
+
+/* Mask out flags that are inappropriate for the given type of inode. */
+static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
+{
+ if (S_ISDIR(mode))
+ return flags;
+ else if (S_ISREG(mode))
+ return flags & ~FS_DIRSYNC_FL;
+ else
+ return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
+}
+
+/*
+ * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
+ */
+static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
+{
+ unsigned int iflags = 0;
+
+ if (flags & BTRFS_INODE_SYNC)
+ iflags |= FS_SYNC_FL;
+ if (flags & BTRFS_INODE_IMMUTABLE)
+ iflags |= FS_IMMUTABLE_FL;
+ if (flags & BTRFS_INODE_APPEND)
+ iflags |= FS_APPEND_FL;
+ if (flags & BTRFS_INODE_NODUMP)
+ iflags |= FS_NODUMP_FL;
+ if (flags & BTRFS_INODE_NOATIME)
+ iflags |= FS_NOATIME_FL;
+ if (flags & BTRFS_INODE_DIRSYNC)
+ iflags |= FS_DIRSYNC_FL;
+ if (flags & BTRFS_INODE_NODATACOW)
+ iflags |= FS_NOCOW_FL;
+
+ if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
+ iflags |= FS_COMPR_FL;
+ else if (flags & BTRFS_INODE_NOCOMPRESS)
+ iflags |= FS_NOCOMP_FL;
+
+ return iflags;
+}
+
+/*
+ * Update inode->i_flags based on the btrfs internal flags.
+ */
+void btrfs_update_iflags(struct inode *inode)
+{
+ struct btrfs_inode *ip = BTRFS_I(inode);
+
+ inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
+
+ if (ip->flags & BTRFS_INODE_SYNC)
+ inode->i_flags |= S_SYNC;
+ if (ip->flags & BTRFS_INODE_IMMUTABLE)
+ inode->i_flags |= S_IMMUTABLE;
+ if (ip->flags & BTRFS_INODE_APPEND)
+ inode->i_flags |= S_APPEND;
+ if (ip->flags & BTRFS_INODE_NOATIME)
+ inode->i_flags |= S_NOATIME;
+ if (ip->flags & BTRFS_INODE_DIRSYNC)
+ inode->i_flags |= S_DIRSYNC;
+}
+
+/*
+ * Inherit flags from the parent inode.
+ *
+ * Currently only the compression flags and the cow flags are inherited.
+ */
+void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
+{
+ unsigned int flags;
+
+ if (!dir)
+ return;
+
+ flags = BTRFS_I(dir)->flags;
+
+ if (flags & BTRFS_INODE_NOCOMPRESS) {
+ BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
+ BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
+ } else if (flags & BTRFS_INODE_COMPRESS) {
+ BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
+ BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
+ }
+
+ if (flags & BTRFS_INODE_NODATACOW)
+ BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
+
+ btrfs_update_iflags(inode);
+}
+
+static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
+{
+ struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
+ unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
+
+ if (copy_to_user(arg, &flags, sizeof(flags)))
+ return -EFAULT;
+ return 0;
+}
+
+static int check_flags(unsigned int flags)
+{
+ if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
+ FS_NOATIME_FL | FS_NODUMP_FL | \
+ FS_SYNC_FL | FS_DIRSYNC_FL | \
+ FS_NOCOMP_FL | FS_COMPR_FL |
+ FS_NOCOW_FL))
+ return -EOPNOTSUPP;
+
+ if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
+{
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct btrfs_inode *ip = BTRFS_I(inode);
+ struct btrfs_root *root = ip->root;
+ struct btrfs_trans_handle *trans;
+ unsigned int flags, oldflags;
+ int ret;
+ u64 ip_oldflags;
+ unsigned int i_oldflags;
+
+ if (btrfs_root_readonly(root))
+ return -EROFS;
+
+ if (copy_from_user(&flags, arg, sizeof(flags)))
+ return -EFAULT;
+
+ ret = check_flags(flags);
+ if (ret)
+ return ret;
+
+ if (!inode_owner_or_capable(inode))
+ return -EACCES;
+
+ mutex_lock(&inode->i_mutex);
+
+ ip_oldflags = ip->flags;
+ i_oldflags = inode->i_flags;
+
+ flags = btrfs_mask_flags(inode->i_mode, flags);
+ oldflags = btrfs_flags_to_ioctl(ip->flags);
+ if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
+ if (!capable(CAP_LINUX_IMMUTABLE)) {
+ ret = -EPERM;
+ goto out_unlock;
+ }
+ }
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ goto out_unlock;
+
+ if (flags & FS_SYNC_FL)
+ ip->flags |= BTRFS_INODE_SYNC;
+ else
+ ip->flags &= ~BTRFS_INODE_SYNC;
+ if (flags & FS_IMMUTABLE_FL)
+ ip->flags |= BTRFS_INODE_IMMUTABLE;
+ else
+ ip->flags &= ~BTRFS_INODE_IMMUTABLE;
+ if (flags & FS_APPEND_FL)
+ ip->flags |= BTRFS_INODE_APPEND;
+ else
+ ip->flags &= ~BTRFS_INODE_APPEND;
+ if (flags & FS_NODUMP_FL)
+ ip->flags |= BTRFS_INODE_NODUMP;
+ else
+ ip->flags &= ~BTRFS_INODE_NODUMP;
+ if (flags & FS_NOATIME_FL)
+ ip->flags |= BTRFS_INODE_NOATIME;
+ else
+ ip->flags &= ~BTRFS_INODE_NOATIME;
+ if (flags & FS_DIRSYNC_FL)
+ ip->flags |= BTRFS_INODE_DIRSYNC;
+ else
+ ip->flags &= ~BTRFS_INODE_DIRSYNC;
+ if (flags & FS_NOCOW_FL)
+ ip->flags |= BTRFS_INODE_NODATACOW;
+ else
+ ip->flags &= ~BTRFS_INODE_NODATACOW;
+
+ /*
+ * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
+ * flag may be changed automatically if compression code won't make
+ * things smaller.
+ */
+ if (flags & FS_NOCOMP_FL) {
+ ip->flags &= ~BTRFS_INODE_COMPRESS;
+ ip->flags |= BTRFS_INODE_NOCOMPRESS;
+ } else if (flags & FS_COMPR_FL) {
+ ip->flags |= BTRFS_INODE_COMPRESS;
+ ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
+ } else {
+ ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
+ }
+
+ trans = btrfs_start_transaction(root, 1);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out_drop;
+ }
+
+ btrfs_update_iflags(inode);
+ inode->i_ctime = CURRENT_TIME;
+ ret = btrfs_update_inode(trans, root, inode);
+
+ btrfs_end_transaction(trans, root);
+ out_drop:
+ if (ret) {
+ ip->flags = ip_oldflags;
+ inode->i_flags = i_oldflags;
+ }
+
+ mnt_drop_write_file(file);
+ out_unlock:
+ mutex_unlock(&inode->i_mutex);
+ return ret;
+}
+
+static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
+{
+ struct inode *inode = file->f_path.dentry->d_inode;
+
+ return put_user(inode->i_generation, arg);
+}
+
+static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
+{
+ struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
+ struct btrfs_device *device;
+ struct request_queue *q;
+ struct fstrim_range range;
+ u64 minlen = ULLONG_MAX;
+ u64 num_devices = 0;
+ u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
+ dev_list) {
+ if (!device->bdev)
+ continue;
+ q = bdev_get_queue(device->bdev);
+ if (blk_queue_discard(q)) {
+ num_devices++;
+ minlen = min((u64)q->limits.discard_granularity,
+ minlen);
+ }
+ }
+ rcu_read_unlock();
+
+ if (!num_devices)
+ return -EOPNOTSUPP;
+ if (copy_from_user(&range, arg, sizeof(range)))
+ return -EFAULT;
+ if (range.start > total_bytes)
+ return -EINVAL;
+
+ range.len = min(range.len, total_bytes - range.start);
+ range.minlen = max(range.minlen, minlen);
+ ret = btrfs_trim_fs(fs_info->tree_root, &range);
+ if (ret < 0)
+ return ret;
+
+ if (copy_to_user(arg, &range, sizeof(range)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static noinline int create_subvol(struct btrfs_root *root,
+ struct dentry *dentry,
+ char *name, int namelen,
+ u64 *async_transid)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_key key;
+ struct btrfs_root_item root_item;
+ struct btrfs_inode_item *inode_item;
+ struct extent_buffer *leaf;
+ struct btrfs_root *new_root;
+ struct dentry *parent = dentry->d_parent;
+ struct inode *dir;
+ int ret;
+ int err;
+ u64 objectid;
+ u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
+ u64 index = 0;
+
+ ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
+ if (ret)
+ return ret;
+
+ dir = parent->d_inode;
+
+ /*
+ * 1 - inode item
+ * 2 - refs
+ * 1 - root item
+ * 2 - dir items
+ */
+ trans = btrfs_start_transaction(root, 6);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
+ leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
+ 0, objectid, NULL, 0, 0, 0, 0);
+ if (IS_ERR(leaf)) {
+ ret = PTR_ERR(leaf);
+ goto fail;
+ }
+
+ memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
+ btrfs_set_header_bytenr(leaf, leaf->start);
+ btrfs_set_header_generation(leaf, trans->transid);
+ btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
+ btrfs_set_header_owner(leaf, objectid);
+
+ write_extent_buffer(leaf, root->fs_info->fsid,
+ (unsigned long)btrfs_header_fsid(leaf),
+ BTRFS_FSID_SIZE);
+ write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
+ (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
+ BTRFS_UUID_SIZE);
+ btrfs_mark_buffer_dirty(leaf);
+
+ inode_item = &root_item.inode;
+ memset(inode_item, 0, sizeof(*inode_item));
+ inode_item->generation = cpu_to_le64(1);
+ inode_item->size = cpu_to_le64(3);
+ inode_item->nlink = cpu_to_le32(1);
+ inode_item->nbytes = cpu_to_le64(root->leafsize);
+ inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
+
+ root_item.flags = 0;
+ root_item.byte_limit = 0;
+ inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
+
+ btrfs_set_root_bytenr(&root_item, leaf->start);
+ btrfs_set_root_generation(&root_item, trans->transid);
+ btrfs_set_root_level(&root_item, 0);
+ btrfs_set_root_refs(&root_item, 1);
+ btrfs_set_root_used(&root_item, leaf->len);
+ btrfs_set_root_last_snapshot(&root_item, 0);
+
+ memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
+ root_item.drop_level = 0;
+
+ btrfs_tree_unlock(leaf);
+ free_extent_buffer(leaf);
+ leaf = NULL;
+
+ btrfs_set_root_dirid(&root_item, new_dirid);
+
+ key.objectid = objectid;
+ key.offset = 0;
+ btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+ ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
+ &root_item);
+ if (ret)
+ goto fail;
+
+ key.offset = (u64)-1;
+ new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
+ if (IS_ERR(new_root)) {
+ btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
+ ret = PTR_ERR(new_root);
+ goto fail;
+ }
+
+ btrfs_record_root_in_trans(trans, new_root);
+
+ ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
+ if (ret) {
+ /* We potentially lose an unused inode item here */
+ btrfs_abort_transaction(trans, root, ret);
+ goto fail;
+ }
+
+ /*
+ * insert the directory item
+ */
+ ret = btrfs_set_inode_index(dir, &index);
+ if (ret) {
+ btrfs_abort_transaction(trans, root, ret);
+ goto fail;
+ }
+
+ ret = btrfs_insert_dir_item(trans, root,
+ name, namelen, dir, &key,
+ BTRFS_FT_DIR, index);
+ if (ret) {
+ btrfs_abort_transaction(trans, root, ret);
+ goto fail;
+ }
+
+ btrfs_i_size_write(dir, dir->i_size + namelen * 2);
+ ret = btrfs_update_inode(trans, root, dir);
+ BUG_ON(ret);
+
+ ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
+ objectid, root->root_key.objectid,
+ btrfs_ino(dir), index, name, namelen);
+
+ BUG_ON(ret);
+
+ d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
+fail:
+ if (async_transid) {
+ *async_transid = trans->transid;
+ err = btrfs_commit_transaction_async(trans, root, 1);
+ } else {
+ err = btrfs_commit_transaction(trans, root);
+ }
+ if (err && !ret)
+ ret = err;
+ return ret;
+}
+
+static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
+ char *name, int namelen, u64 *async_transid,
+ bool readonly)
+{
+ struct inode *inode;
+ struct btrfs_pending_snapshot *pending_snapshot;
+ struct btrfs_trans_handle *trans;
+ int ret;
+
+ if (!root->ref_cows)
+ return -EINVAL;
+
+ pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
+ if (!pending_snapshot)
+ return -ENOMEM;
+
+ btrfs_init_block_rsv(&pending_snapshot->block_rsv);
+ pending_snapshot->dentry = dentry;
+ pending_snapshot->root = root;
+ pending_snapshot->readonly = readonly;
+
+ trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto fail;
+ }
+
+ ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
+ BUG_ON(ret);
+
+ spin_lock(&root->fs_info->trans_lock);
+ list_add(&pending_snapshot->list,
+ &trans->transaction->pending_snapshots);
+ spin_unlock(&root->fs_info->trans_lock);
+ if (async_transid) {
+ *async_transid = trans->transid;
+ ret = btrfs_commit_transaction_async(trans,
+ root->fs_info->extent_root, 1);
+ } else {
+ ret = btrfs_commit_transaction(trans,
+ root->fs_info->extent_root);
+ }
+ BUG_ON(ret);
+
+ ret = pending_snapshot->error;
+ if (ret)
+ goto fail;
+
+ ret = btrfs_orphan_cleanup(pending_snapshot->snap);
+ if (ret)
+ goto fail;
+
+ inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
+ if (IS_ERR(inode)) {
+ ret = PTR_ERR(inode);
+ goto fail;
+ }
+ BUG_ON(!inode);
+ d_instantiate(dentry, inode);
+ ret = 0;
+fail:
+ kfree(pending_snapshot);
+ return ret;
+}
+
+/* copy of check_sticky in fs/namei.c()
+* It's inline, so penalty for filesystems that don't use sticky bit is
+* minimal.
+*/
+static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
+{
+ uid_t fsuid = current_fsuid();
+
+ if (!(dir->i_mode & S_ISVTX))
+ return 0;
+ if (inode->i_uid == fsuid)
+ return 0;
+ if (dir->i_uid == fsuid)
+ return 0;
+ return !capable(CAP_FOWNER);
+}
+
+/* copy of may_delete in fs/namei.c()
+ * Check whether we can remove a link victim from directory dir, check
+ * whether the type of victim is right.
+ * 1. We can't do it if dir is read-only (done in permission())
+ * 2. We should have write and exec permissions on dir
+ * 3. We can't remove anything from append-only dir
+ * 4. We can't do anything with immutable dir (done in permission())
+ * 5. If the sticky bit on dir is set we should either
+ * a. be owner of dir, or
+ * b. be owner of victim, or
+ * c. have CAP_FOWNER capability
+ * 6. If the victim is append-only or immutable we can't do antyhing with
+ * links pointing to it.
+ * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
+ * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
+ * 9. We can't remove a root or mountpoint.
+ * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
+ * nfs_async_unlink().
+ */
+
+static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
+{
+ int error;
+
+ if (!victim->d_inode)
+ return -ENOENT;
+
+ BUG_ON(victim->d_parent->d_inode != dir);
+ audit_inode_child(victim, dir);
+
+ error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ if (error)
+ return error;
+ if (IS_APPEND(dir))
+ return -EPERM;
+ if (btrfs_check_sticky(dir, victim->d_inode)||
+ IS_APPEND(victim->d_inode)||
+ IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
+ return -EPERM;
+ if (isdir) {
+ if (!S_ISDIR(victim->d_inode->i_mode))
+ return -ENOTDIR;
+ if (IS_ROOT(victim))
+ return -EBUSY;
+ } else if (S_ISDIR(victim->d_inode->i_mode))
+ return -EISDIR;
+ if (IS_DEADDIR(dir))
+ return -ENOENT;
+ if (victim->d_flags & DCACHE_NFSFS_RENAMED)
+ return -EBUSY;
+ return 0;
+}
+
+/* copy of may_create in fs/namei.c() */
+static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
+{
+ if (child->d_inode)
+ return -EEXIST;
+ if (IS_DEADDIR(dir))
+ return -ENOENT;
+ return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+}
+
+/*
+ * Create a new subvolume below @parent. This is largely modeled after
+ * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
+ * inside this filesystem so it's quite a bit simpler.
+ */
+static noinline int btrfs_mksubvol(struct path *parent,
+ char *name, int namelen,
+ struct btrfs_root *snap_src,
+ u64 *async_transid, bool readonly)
+{
+ struct inode *dir = parent->dentry->d_inode;
+ struct dentry *dentry;
+ int error;
+
+ mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
+
+ dentry = lookup_one_len(name, parent->dentry, namelen);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto out_unlock;
+
+ error = -EEXIST;
+ if (dentry->d_inode)
+ goto out_dput;
+
+ error = mnt_want_write(parent->mnt);
+ if (error)
+ goto out_dput;
+
+ error = btrfs_may_create(dir, dentry);
+ if (error)
+ goto out_drop_write;
+
+ down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
+
+ if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
+ goto out_up_read;
+
+ if (snap_src) {
+ error = create_snapshot(snap_src, dentry,
+ name, namelen, async_transid, readonly);
+ } else {
+ error = create_subvol(BTRFS_I(dir)->root, dentry,
+ name, namelen, async_transid);
+ }
+ if (!error)
+ fsnotify_mkdir(dir, dentry);
+out_up_read:
+ up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
+out_drop_write:
+ mnt_drop_write(parent->mnt);
+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;
+}
+
+/*
+ * Validaty check of prev em and next em:
+ * 1) no prev/next em
+ * 2) prev/next em is an hole/inline extent
+ */
+static int check_adjacent_extents(struct inode *inode, struct extent_map *em)
+{
+ struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ struct extent_map *prev = NULL, *next = NULL;
+ int ret = 0;
+
+ read_lock(&em_tree->lock);
+ prev = lookup_extent_mapping(em_tree, em->start - 1, (u64)-1);
+ next = lookup_extent_mapping(em_tree, em->start + em->len, (u64)-1);
+ read_unlock(&em_tree->lock);
+
+ if ((!prev || prev->block_start >= EXTENT_MAP_LAST_BYTE) &&
+ (!next || next->block_start >= EXTENT_MAP_LAST_BYTE))
+ ret = 1;
+ free_extent_map(prev);
+ free_extent_map(next);
+
+ return ret;
+}
+
+static int should_defrag_range(struct inode *inode, u64 start, u64 len,
+ int thresh, u64 *last_len, u64 *skip,
+ u64 *defrag_end)
+{
+ struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+ struct extent_map *em = NULL;
+ struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ int ret = 1;
+
+ /*
+ * make sure that once we start defragging an extent, we keep on
+ * defragging it
+ */
+ if (start < *defrag_end)
+ return 1;
+
+ *skip = 0;
+
+ /*
+ * hopefully we have this extent in the tree already, try without
+ * the full extent lock
+ */
+ read_lock(&em_tree->lock);
+ em = lookup_extent_mapping(em_tree, start, len);
+ read_unlock(&em_tree->lock);
+
+ if (!em) {
+ /* get the big lock and read metadata off disk */
+ lock_extent(io_tree, start, start + len - 1);
+ em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
+ unlock_extent(io_tree, start, start + len - 1);
+
+ if (IS_ERR(em))
+ return 0;
+ }
+
+ /* this will cover holes, and inline extents */
+ if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
+ ret = 0;
+ goto out;
+ }
+
+ /* If we have nothing to merge with us, just skip. */
+ if (check_adjacent_extents(inode, em)) {
+ ret = 0;
+ goto out;
+ }
+
+ /*
+ * we hit a real extent, if it is big don't bother defragging it again
+ */
+ if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
+ ret = 0;
+
+out:
+ /*
+ * last_len ends up being a counter of how many bytes we've defragged.
+ * every time we choose not to defrag an extent, we reset *last_len
+ * so that the next tiny extent will force a defrag.
+ *
+ * The end result of this is that tiny extents before a single big
+ * extent will force at least part of that big extent to be defragged.
+ */
+ if (ret) {
+ *defrag_end = extent_map_end(em);
+ } else {
+ *last_len = 0;
+ *skip = extent_map_end(em);
+ *defrag_end = 0;
+ }
+
+ free_extent_map(em);
+ return ret;
+}
+
+/*
+ * it doesn't do much good to defrag one or two pages
+ * at a time. This pulls in a nice chunk of pages
+ * to COW and defrag.
+ *
+ * It also makes sure the delalloc code has enough
+ * dirty data to avoid making new small extents as part
+ * of the defrag
+ *
+ * It's a good idea to start RA on this range
+ * before calling this.
+ */
+static int cluster_pages_for_defrag(struct inode *inode,
+ struct page **pages,
+ unsigned long start_index,
+ int num_pages)
+{
+ unsigned long file_end;
+ u64 isize = i_size_read(inode);
+ u64 page_start;
+ u64 page_end;
+ u64 page_cnt;
+ int ret;
+ int i;
+ int i_done;
+ struct btrfs_ordered_extent *ordered;
+ struct extent_state *cached_state = NULL;
+ struct extent_io_tree *tree;
+ gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
+
+ file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
+ if (!isize || start_index > file_end)
+ return 0;
+
+ page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
+
+ ret = btrfs_delalloc_reserve_space(inode,
+ page_cnt << PAGE_CACHE_SHIFT);
+ if (ret)
+ return ret;
+ i_done = 0;
+ tree = &BTRFS_I(inode)->io_tree;
+
+ /* step one, lock all the pages */
+ for (i = 0; i < page_cnt; i++) {
+ struct page *page;
+again:
+ page = find_or_create_page(inode->i_mapping,
+ start_index + i, mask);
+ if (!page)
+ break;
+
+ page_start = page_offset(page);
+ page_end = page_start + PAGE_CACHE_SIZE - 1;
+ while (1) {
+ lock_extent(tree, page_start, page_end);
+ ordered = btrfs_lookup_ordered_extent(inode,
+ page_start);
+ unlock_extent(tree, page_start, page_end);
+ if (!ordered)
+ break;
+
+ unlock_page(page);
+ btrfs_start_ordered_extent(inode, ordered, 1);
+ btrfs_put_ordered_extent(ordered);
+ lock_page(page);
+ /*
+ * we unlocked the page above, so we need check if
+ * it was released or not.
+ */
+ if (page->mapping != inode->i_mapping) {
+ unlock_page(page);
+ page_cache_release(page);
+ goto again;
+ }
+ }
+
+ if (!PageUptodate(page)) {
+ btrfs_readpage(NULL, page);
+ lock_page(page);
+ if (!PageUptodate(page)) {
+ unlock_page(page);
+ page_cache_release(page);
+ ret = -EIO;
+ break;
+ }
+ }
+
+ if (page->mapping != inode->i_mapping) {
+ unlock_page(page);
+ page_cache_release(page);
+ goto again;
+ }
+
+ pages[i] = page;
+ i_done++;
+ }
+ if (!i_done || ret)
+ goto out;
+
+ if (!(inode->i_sb->s_flags & MS_ACTIVE))
+ goto out;
+
+ /*
+ * so now we have a nice long stream of locked
+ * and up to date pages, lets wait on them
+ */
+ for (i = 0; i < i_done; i++)
+ wait_on_page_writeback(pages[i]);
+
+ page_start = page_offset(pages[0]);
+ page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
+
+ lock_extent_bits(&BTRFS_I(inode)->io_tree,
+ page_start, page_end - 1, 0, &cached_state);
+ clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
+ page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
+ EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
+ GFP_NOFS);
+
+ if (i_done != page_cnt) {
+ spin_lock(&BTRFS_I(inode)->lock);
+ BTRFS_I(inode)->outstanding_extents++;
+ spin_unlock(&BTRFS_I(inode)->lock);
+ btrfs_delalloc_release_space(inode,
+ (page_cnt - i_done) << PAGE_CACHE_SHIFT);
+ }
+
+
+ btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
+ &cached_state);
+
+ unlock_extent_cached(&BTRFS_I(inode)->io_tree,
+ page_start, page_end - 1, &cached_state,
+ GFP_NOFS);
+
+ for (i = 0; i < i_done; i++) {
+ clear_page_dirty_for_io(pages[i]);
+ ClearPageChecked(pages[i]);
+ set_page_extent_mapped(pages[i]);
+ set_page_dirty(pages[i]);
+ unlock_page(pages[i]);
+ page_cache_release(pages[i]);
+ }
+ return i_done;
+out:
+ for (i = 0; i < i_done; i++) {
+ unlock_page(pages[i]);
+ page_cache_release(pages[i]);
+ }
+ btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
+ return ret;
+
+}
+
+int btrfs_defrag_file(struct inode *inode, struct file *file,
+ struct btrfs_ioctl_defrag_range_args *range,
+ u64 newer_than, unsigned long max_to_defrag)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_super_block *disk_super;
+ struct file_ra_state *ra = NULL;
+ unsigned long last_index;
+ u64 isize = i_size_read(inode);
+ u64 features;
+ u64 last_len = 0;
+ u64 skip = 0;
+ u64 defrag_end = 0;
+ u64 newer_off = range->start;
+ unsigned long i;
+ unsigned long ra_index = 0;
+ int ret;
+ int defrag_count = 0;
+ int compress_type = BTRFS_COMPRESS_ZLIB;
+ int extent_thresh = range->extent_thresh;
+ int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
+ int cluster = max_cluster;
+ u64 new_align = ~((u64)128 * 1024 - 1);
+ struct page **pages = NULL;
+
+ if (extent_thresh == 0)
+ extent_thresh = 256 * 1024;
+
+ if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
+ if (range->compress_type > BTRFS_COMPRESS_TYPES)
+ return -EINVAL;
+ if (range->compress_type)
+ compress_type = range->compress_type;
+ }
+
+ if (isize == 0)
+ return 0;
+
+ /*
+ * if we were not given a file, allocate a readahead
+ * context
+ */
+ if (!file) {
+ ra = kzalloc(sizeof(*ra), GFP_NOFS);
+ if (!ra)
+ return -ENOMEM;
+ file_ra_state_init(ra, inode->i_mapping);
+ } else {
+ ra = &file->f_ra;
+ }
+
+ pages = kmalloc(sizeof(struct page *) * max_cluster,
+ GFP_NOFS);
+ if (!pages) {
+ ret = -ENOMEM;
+ goto out_ra;
+ }
+
+ /* find the last page to defrag */
+ if (range->start + range->len > range->start) {
+ last_index = min_t(u64, isize - 1,
+ range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
+ } else {
+ last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
+ }
+
+ if (newer_than) {
+ ret = find_new_extents(root, inode, newer_than,
+ &newer_off, 64 * 1024);
+ if (!ret) {
+ range->start = newer_off;
+ /*
+ * we always align our defrag to help keep
+ * the extents in the file evenly spaced
+ */
+ i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
+ } else
+ goto out_ra;
+ } else {
+ i = range->start >> PAGE_CACHE_SHIFT;
+ }
+ if (!max_to_defrag)
+ max_to_defrag = last_index + 1;
+
+ /*
+ * make writeback starts from i, so the defrag range can be
+ * written sequentially.
+ */
+ if (i < inode->i_mapping->writeback_index)
+ inode->i_mapping->writeback_index = i;
+
+ while (i <= last_index && defrag_count < max_to_defrag &&
+ (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
+ PAGE_CACHE_SHIFT)) {
+ /*
+ * make sure we stop running if someone unmounts
+ * the FS
+ */
+ if (!(inode->i_sb->s_flags & MS_ACTIVE))
+ break;
+
+ if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
+ PAGE_CACHE_SIZE, extent_thresh,
+ &last_len, &skip, &defrag_end)) {
+ unsigned long next;
+ /*
+ * the should_defrag function tells us how much to skip
+ * bump our counter by the suggested amount
+ */
+ next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ i = max(i + 1, next);
+ continue;
+ }
+
+ if (!newer_than) {
+ cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
+ PAGE_CACHE_SHIFT) - i;
+ cluster = min(cluster, max_cluster);
+ } else {
+ cluster = max_cluster;
+ }
+
+ if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
+ BTRFS_I(inode)->force_compress = compress_type;
+
+ if (i + cluster > ra_index) {
+ ra_index = max(i, ra_index);
+ btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
+ cluster);
+ ra_index += max_cluster;
+ }
+
+ mutex_lock(&inode->i_mutex);
+ ret = cluster_pages_for_defrag(inode, pages, i, cluster);
+ if (ret < 0) {
+ mutex_unlock(&inode->i_mutex);
+ goto out_ra;
+ }
+
+ defrag_count += ret;
+ balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
+ mutex_unlock(&inode->i_mutex);
+
+ if (newer_than) {
+ if (newer_off == (u64)-1)
+ break;
+
+ if (ret > 0)
+ i += ret;
+
+ newer_off = max(newer_off + 1,
+ (u64)i << PAGE_CACHE_SHIFT);
+
+ ret = find_new_extents(root, inode,
+ newer_than, &newer_off,
+ 64 * 1024);
+ if (!ret) {
+ range->start = newer_off;
+ i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
+ } else {
+ break;
+ }
+ } else {
+ if (ret > 0) {
+ i += ret;
+ last_len += ret << PAGE_CACHE_SHIFT;
+ } else {
+ i++;
+ last_len = 0;
+ }
+ }
+ }
+
+ if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
+ filemap_flush(inode->i_mapping);
+
+ if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
+ /* the filemap_flush will queue IO into the worker threads, but
+ * we have to make sure the IO is actually started and that
+ * ordered extents get created before we return
+ */
+ atomic_inc(&root->fs_info->async_submit_draining);
+ while (atomic_read(&root->fs_info->nr_async_submits) ||
+ atomic_read(&root->fs_info->async_delalloc_pages)) {
+ wait_event(root->fs_info->async_submit_wait,
+ (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
+ atomic_read(&root->fs_info->async_delalloc_pages) == 0));
+ }
+ atomic_dec(&root->fs_info->async_submit_draining);
+
+ mutex_lock(&inode->i_mutex);
+ BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
+ mutex_unlock(&inode->i_mutex);
+ }
+
+ disk_super = root->fs_info->super_copy;
+ features = btrfs_super_incompat_flags(disk_super);
+ if (range->compress_type == BTRFS_COMPRESS_LZO) {
+ features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
+ btrfs_set_super_incompat_flags(disk_super, features);
+ }
+
+ ret = defrag_count;
+
+out_ra:
+ if (!file)
+ kfree(ra);
+ kfree(pages);
+ return ret;
+}
+
+static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
+ void __user *arg)
+{
+ u64 new_size;
+ u64 old_size;
+ u64 devid = 1;
+ struct btrfs_ioctl_vol_args *vol_args;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_device *device = NULL;
+ char *sizestr;
+ char *devstr = NULL;
+ int ret = 0;
+ int mod = 0;
+
+ if (root->fs_info->sb->s_flags & MS_RDONLY)
+ return -EROFS;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ mutex_lock(&root->fs_info->volume_mutex);
+ if (root->fs_info->balance_ctl) {
+ printk(KERN_INFO "btrfs: balance in progress\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args)) {
+ ret = PTR_ERR(vol_args);
+ goto out;
+ }
+
+ vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
+
+ sizestr = vol_args->name;
+ devstr = strchr(sizestr, ':');
+ if (devstr) {
+ char *end;
+ sizestr = devstr + 1;
+ *devstr = '\0';
+ devstr = vol_args->name;
+ devid = simple_strtoull(devstr, &end, 10);
+ printk(KERN_INFO "btrfs: resizing devid %llu\n",
+ (unsigned long long)devid);
+ }
+ device = btrfs_find_device(root, devid, NULL, NULL);
+ if (!device) {
+ printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
+ (unsigned long long)devid);
+ ret = -EINVAL;
+ goto out_free;
+ }
+ if (!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(KERN_INFO "btrfs: new size for %s is %llu\n",
+ 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_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+ struct file *src_file;
+ int namelen;
+ int ret = 0;
+
+ if (root->fs_info->sb->s_flags & MS_RDONLY)
+ return -EROFS;
+
+ namelen = strlen(name);
+ if (strchr(name, '/')) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (name[0] == '.' &&
+ (namelen == 1 || (name[1] == '.' && namelen == 2))) {
+ ret = -EEXIST;
+ goto out;
+ }
+
+ if (subvol) {
+ ret = btrfs_mksubvol(&file->f_path, name, namelen,
+ NULL, transid, readonly);
+ } else {
+ struct inode *src_inode;
+ src_file = fget(fd);
+ if (!src_file) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ src_inode = src_file->f_path.dentry->d_inode;
+ if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
+ printk(KERN_INFO "btrfs: Snapshot src from "
+ "another FS\n");
+ ret = -EINVAL;
+ fput(src_file);
+ goto out;
+ }
+ ret = btrfs_mksubvol(&file->f_path, name, namelen,
+ BTRFS_I(src_inode)->root,
+ transid, readonly);
+ fput(src_file);
+ }
+out:
+ return ret;
+}
+
+static noinline int btrfs_ioctl_snap_create(struct file *file,
+ void __user *arg, int subvol)
+{
+ struct btrfs_ioctl_vol_args *vol_args;
+ int ret;
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args))
+ return PTR_ERR(vol_args);
+ vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
+
+ ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
+ vol_args->fd, subvol,
+ NULL, false);
+
+ kfree(vol_args);
+ return ret;
+}
+
+static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
+ void __user *arg, int subvol)
+{
+ struct btrfs_ioctl_vol_args_v2 *vol_args;
+ int ret;
+ u64 transid = 0;
+ u64 *ptr = NULL;
+ bool readonly = false;
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args))
+ return PTR_ERR(vol_args);
+ vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
+
+ if (vol_args->flags &
+ ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
+ ptr = &transid;
+ if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
+ readonly = true;
+
+ ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
+ vol_args->fd, subvol,
+ ptr, readonly);
+
+ if (ret == 0 && ptr &&
+ copy_to_user(arg +
+ offsetof(struct btrfs_ioctl_vol_args_v2,
+ transid), ptr, sizeof(*ptr)))
+ ret = -EFAULT;
+out:
+ kfree(vol_args);
+ return ret;
+}
+
+static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
+ void __user *arg)
+{
+ struct inode *inode = fdentry(file)->d_inode;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ int ret = 0;
+ u64 flags = 0;
+
+ if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
+ return -EINVAL;
+
+ down_read(&root->fs_info->subvol_sem);
+ if (btrfs_root_readonly(root))
+ flags |= BTRFS_SUBVOL_RDONLY;
+ up_read(&root->fs_info->subvol_sem);
+
+ if (copy_to_user(arg, &flags, sizeof(flags)))
+ ret = -EFAULT;
+
+ return ret;
+}
+
+static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
+ void __user *arg)
+{
+ struct inode *inode = fdentry(file)->d_inode;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+ u64 root_flags;
+ u64 flags;
+ int ret = 0;
+
+ if (root->fs_info->sb->s_flags & MS_RDONLY)
+ return -EROFS;
+
+ if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
+ return -EINVAL;
+
+ if (copy_from_user(&flags, arg, sizeof(flags)))
+ return -EFAULT;
+
+ if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
+ return -EINVAL;
+
+ if (flags & ~BTRFS_SUBVOL_RDONLY)
+ return -EOPNOTSUPP;
+
+ if (!inode_owner_or_capable(inode))
+ return -EACCES;
+
+ down_write(&root->fs_info->subvol_sem);
+
+ /* nothing to do */
+ if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
+ goto out;
+
+ root_flags = btrfs_root_flags(&root->root_item);
+ if (flags & BTRFS_SUBVOL_RDONLY)
+ btrfs_set_root_flags(&root->root_item,
+ root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
+ else
+ btrfs_set_root_flags(&root->root_item,
+ root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
+
+ trans = btrfs_start_transaction(root, 1);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out_reset;
+ }
+
+ ret = btrfs_update_root(trans, root->fs_info->tree_root,
+ &root->root_key, &root->root_item);
+
+ btrfs_commit_transaction(trans, root);
+out_reset:
+ if (ret)
+ btrfs_set_root_flags(&root->root_item, root_flags);
+out:
+ up_write(&root->fs_info->subvol_sem);
+ return ret;
+}
+
+/*
+ * helper to check if the subvolume references other subvolumes
+ */
+static noinline int may_destroy_subvol(struct btrfs_root *root)
+{
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = root->root_key.objectid;
+ key.type = BTRFS_ROOT_REF_KEY;
+ key.offset = (u64)-1;
+
+ ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
+ &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+ BUG_ON(ret == 0);
+
+ ret = 0;
+ if (path->slots[0] > 0) {
+ path->slots[0]--;
+ btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
+ if (key.objectid == root->root_key.objectid &&
+ key.type == BTRFS_ROOT_REF_KEY)
+ ret = -ENOTEMPTY;
+ }
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static noinline int key_in_sk(struct btrfs_key *key,
+ struct btrfs_ioctl_search_key *sk)
+{
+ struct btrfs_key test;
+ int ret;
+
+ test.objectid = sk->min_objectid;
+ test.type = sk->min_type;
+ test.offset = sk->min_offset;
+
+ ret = btrfs_comp_cpu_keys(key, &test);
+ if (ret < 0)
+ return 0;
+
+ test.objectid = sk->max_objectid;
+ test.type = sk->max_type;
+ test.offset = sk->max_offset;
+
+ ret = btrfs_comp_cpu_keys(key, &test);
+ if (ret > 0)
+ return 0;
+ return 1;
+}
+
+static noinline int copy_to_sk(struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_key *key,
+ struct btrfs_ioctl_search_key *sk,
+ char *buf,
+ unsigned long *sk_offset,
+ int *num_found)
+{
+ u64 found_transid;
+ struct extent_buffer *leaf;
+ struct btrfs_ioctl_search_header sh;
+ unsigned long item_off;
+ unsigned long item_len;
+ int nritems;
+ int i;
+ int slot;
+ int ret = 0;
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ nritems = btrfs_header_nritems(leaf);
+
+ if (btrfs_header_generation(leaf) > sk->max_transid) {
+ i = nritems;
+ goto advance_key;
+ }
+ found_transid = btrfs_header_generation(leaf);
+
+ for (i = slot; i < nritems; i++) {
+ item_off = btrfs_item_ptr_offset(leaf, i);
+ item_len = btrfs_item_size_nr(leaf, i);
+
+ btrfs_item_key_to_cpu(leaf, key, i);
+ if (!key_in_sk(key, sk))
+ continue;
+
+ if (sizeof(sh) + item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
+ item_len = 0;
+
+ if (sizeof(sh) + item_len + *sk_offset >
+ BTRFS_SEARCH_ARGS_BUFSIZE) {
+ ret = 1;
+ goto overflow;
+ }
+
+ 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)
+ strncpy(di_args->path, dev->name, sizeof(di_args->path));
+ else
+ di_args->path[0] = '\0';
+
+out:
+ if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
+ ret = -EFAULT;
+
+ kfree(di_args);
+ return ret;
+}
+
+static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
+ u64 off, u64 olen, u64 destoff)
+{
+ struct inode *inode = fdentry(file)->d_inode;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct file *src_file;
+ struct inode *src;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ char *buf;
+ struct btrfs_key key;
+ u32 nritems;
+ int slot;
+ int ret;
+ u64 len = olen;
+ u64 bs = root->fs_info->sb->s_blocksize;
+ u64 hint_byte;
+
+ /*
+ * TODO:
+ * - split compressed inline extents. annoying: we need to
+ * decompress into destination's address_space (the file offset
+ * may change, so source mapping won't do), then recompress (or
+ * otherwise reinsert) a subrange.
+ * - allow ranges within the same file to be cloned (provided
+ * they don't overlap)?
+ */
+
+ /* the destination must be opened for writing */
+ if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
+ return -EINVAL;
+
+ if (btrfs_root_readonly(root))
+ return -EROFS;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ src_file = fget(srcfd);
+ if (!src_file) {
+ ret = -EBADF;
+ goto out_drop_write;
+ }
+
+ src = src_file->f_dentry->d_inode;
+
+ ret = -EINVAL;
+ if (src == inode)
+ goto out_fput;
+
+ /* the src must be open for reading */
+ if (!(src_file->f_mode & FMODE_READ))
+ goto out_fput;
+
+ /* don't make the dst file partly checksummed */
+ if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
+ (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
+ goto out_fput;
+
+ ret = -EISDIR;
+ if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
+ goto out_fput;
+
+ ret = -EXDEV;
+ if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
+ goto out_fput;
+
+ ret = -ENOMEM;
+ buf = vmalloc(btrfs_level_size(root, 0));
+ if (!buf)
+ goto out_fput;
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ vfree(buf);
+ goto out_fput;
+ }
+ path->reada = 2;
+
+ if (inode < src) {
+ mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
+ } else {
+ mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
+ }
+
+ /* determine range to clone */
+ ret = -EINVAL;
+ if (off + len > src->i_size || off + len < off)
+ goto out_unlock;
+ if (len == 0)
+ olen = len = src->i_size - off;
+ /* if we extend to eof, continue to block boundary */
+ if (off + len == src->i_size)
+ len = ALIGN(src->i_size, bs) - off;
+
+ if (len == 0) {
+ ret = 0;
+ goto out_unlock;
+ }
+
+ /* verify the end result is block aligned */
+ if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
+ !IS_ALIGNED(destoff, bs))
+ goto out_unlock;
+
+ if (destoff > inode->i_size) {
+ ret = btrfs_cont_expand(inode, inode->i_size, destoff);
+ if (ret)
+ goto out_unlock;
+ }
+
+ /* truncate page cache pages from target inode range */
+ truncate_inode_pages_range(&inode->i_data, destoff,
+ PAGE_CACHE_ALIGN(destoff + len) - 1);
+
+ /* do any pending delalloc/csum calc on src, one way or
+ another, and lock file content */
+ while (1) {
+ struct btrfs_ordered_extent *ordered;
+ lock_extent(&BTRFS_I(src)->io_tree, off, off+len);
+ ordered = btrfs_lookup_first_ordered_extent(src, off+len);
+ if (!ordered &&
+ !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
+ EXTENT_DELALLOC, 0, NULL))
+ break;
+ unlock_extent(&BTRFS_I(src)->io_tree, off, off+len);
+ if (ordered)
+ btrfs_put_ordered_extent(ordered);
+ btrfs_wait_ordered_range(src, off, len);
+ }
+
+ /* clone data */
+ key.objectid = btrfs_ino(src);
+ key.type = BTRFS_EXTENT_DATA_KEY;
+ key.offset = 0;
+
+ while (1) {
+ /*
+ * note the key will change type as we walk through the
+ * tree.
+ */
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+
+ nritems = btrfs_header_nritems(path->nodes[0]);
+ if (path->slots[0] >= nritems) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret < 0)
+ goto out;
+ if (ret > 0)
+ break;
+ nritems = btrfs_header_nritems(path->nodes[0]);
+ }
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+ if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
+ key.objectid != btrfs_ino(src))
+ break;
+
+ if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
+ struct btrfs_file_extent_item *extent;
+ int type;
+ u32 size;
+ struct btrfs_key new_key;
+ u64 disko = 0, diskl = 0;
+ u64 datao = 0, datal = 0;
+ u8 comp;
+ u64 endoff;
+
+ size = btrfs_item_size_nr(leaf, slot);
+ read_extent_buffer(leaf, buf,
+ btrfs_item_ptr_offset(leaf, slot),
+ size);
+
+ extent = btrfs_item_ptr(leaf, slot,
+ struct btrfs_file_extent_item);
+ comp = btrfs_file_extent_compression(leaf, extent);
+ type = btrfs_file_extent_type(leaf, extent);
+ if (type == BTRFS_FILE_EXTENT_REG ||
+ type == BTRFS_FILE_EXTENT_PREALLOC) {
+ disko = btrfs_file_extent_disk_bytenr(leaf,
+ extent);
+ diskl = btrfs_file_extent_disk_num_bytes(leaf,
+ extent);
+ datao = btrfs_file_extent_offset(leaf, extent);
+ datal = btrfs_file_extent_num_bytes(leaf,
+ extent);
+ } else if (type == BTRFS_FILE_EXTENT_INLINE) {
+ /* take upper bound, may be compressed */
+ datal = btrfs_file_extent_ram_bytes(leaf,
+ extent);
+ }
+ btrfs_release_path(path);
+
+ if (key.offset + datal <= off ||
+ key.offset >= off+len)
+ goto next;
+
+ memcpy(&new_key, &key, sizeof(new_key));
+ new_key.objectid = btrfs_ino(inode);
+ if (off <= key.offset)
+ new_key.offset = key.offset + destoff - off;
+ else
+ new_key.offset = destoff;
+
+ /*
+ * 1 - adjusting old extent (we may have to split it)
+ * 1 - add new extent
+ * 1 - inode update
+ */
+ trans = btrfs_start_transaction(root, 3);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ goto out;
+ }
+
+ if (type == BTRFS_FILE_EXTENT_REG ||
+ type == BTRFS_FILE_EXTENT_PREALLOC) {
+ /*
+ * a | --- range to clone ---| b
+ * | ------------- extent ------------- |
+ */
+
+ /* substract range b */
+ if (key.offset + datal > off + len)
+ datal = off + len - key.offset;
+
+ /* substract range a */
+ if (off > key.offset) {
+ datao += off - key.offset;
+ datal -= off - key.offset;
+ }
+
+ ret = btrfs_drop_extents(trans, inode,
+ new_key.offset,
+ new_key.offset + datal,
+ &hint_byte, 1);
+ if (ret) {
+ btrfs_abort_transaction(trans, root,
+ ret);
+ btrfs_end_transaction(trans, root);
+ goto out;
+ }
+
+ ret = btrfs_insert_empty_item(trans, root, path,
+ &new_key, size);
+ if (ret) {
+ btrfs_abort_transaction(trans, root,
+ ret);
+ btrfs_end_transaction(trans, root);
+ goto out;
+ }
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ write_extent_buffer(leaf, buf,
+ btrfs_item_ptr_offset(leaf, slot),
+ size);
+
+ extent = btrfs_item_ptr(leaf, slot,
+ struct btrfs_file_extent_item);
+
+ /* disko == 0 means it's a hole */
+ if (!disko)
+ datao = 0;
+
+ btrfs_set_file_extent_offset(leaf, extent,
+ datao);
+ btrfs_set_file_extent_num_bytes(leaf, extent,
+ datal);
+ if (disko) {
+ inode_add_bytes(inode, datal);
+ ret = btrfs_inc_extent_ref(trans, root,
+ disko, diskl, 0,
+ root->root_key.objectid,
+ btrfs_ino(inode),
+ new_key.offset - datao,
+ 0);
+ if (ret) {
+ btrfs_abort_transaction(trans,
+ root,
+ ret);
+ btrfs_end_transaction(trans,
+ root);
+ goto out;
+
+ }
+ }
+ } else if (type == BTRFS_FILE_EXTENT_INLINE) {
+ u64 skip = 0;
+ u64 trim = 0;
+ if (off > key.offset) {
+ skip = off - key.offset;
+ new_key.offset += skip;
+ }
+
+ if (key.offset + datal > off+len)
+ trim = key.offset + datal - (off+len);
+
+ if (comp && (skip || trim)) {
+ ret = -EINVAL;
+ btrfs_end_transaction(trans, root);
+ goto out;
+ }
+ size -= skip + trim;
+ datal -= skip + trim;
+
+ ret = btrfs_drop_extents(trans, inode,
+ new_key.offset,
+ new_key.offset + datal,
+ &hint_byte, 1);
+ if (ret) {
+ btrfs_abort_transaction(trans, root,
+ ret);
+ btrfs_end_transaction(trans, root);
+ goto out;
+ }
+
+ ret = btrfs_insert_empty_item(trans, root, path,
+ &new_key, size);
+ if (ret) {
+ btrfs_abort_transaction(trans, root,
+ ret);
+ btrfs_end_transaction(trans, root);
+ goto out;
+ }
+
+ if (skip) {
+ u32 start =
+ btrfs_file_extent_calc_inline_size(0);
+ memmove(buf+start, buf+start+skip,
+ datal);
+ }
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ write_extent_buffer(leaf, buf,
+ btrfs_item_ptr_offset(leaf, slot),
+ size);
+ inode_add_bytes(inode, datal);
+ }
+
+ btrfs_mark_buffer_dirty(leaf);
+ btrfs_release_path(path);
+
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+
+ /*
+ * we round up to the block size at eof when
+ * determining which extents to clone above,
+ * but shouldn't round up the file size
+ */
+ endoff = new_key.offset + datal;
+ if (endoff > destoff+olen)
+ endoff = destoff+olen;
+ if (endoff > inode->i_size)
+ btrfs_i_size_write(inode, endoff);
+
+ ret = btrfs_update_inode(trans, root, inode);
+ if (ret) {
+ btrfs_abort_transaction(trans, root, ret);
+ btrfs_end_transaction(trans, root);
+ goto out;
+ }
+ ret = btrfs_end_transaction(trans, root);
+ }
+next:
+ btrfs_release_path(path);
+ key.offset++;
+ }
+ ret = 0;
+out:
+ btrfs_release_path(path);
+ unlock_extent(&BTRFS_I(src)->io_tree, off, off+len);
+out_unlock:
+ mutex_unlock(&src->i_mutex);
+ mutex_unlock(&inode->i_mutex);
+ vfree(buf);
+ btrfs_free_path(path);
+out_fput:
+ fput(src_file);
+out_drop_write:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
+static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
+{
+ struct btrfs_ioctl_clone_range_args args;
+
+ if (copy_from_user(&args, argp, sizeof(args)))
+ return -EFAULT;
+ return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
+ args.src_length, args.dest_offset);
+}
+
+/*
+ * there are many ways the trans_start and trans_end ioctls can lead
+ * to deadlocks. They should only be used by applications that
+ * basically own the machine, and have a very in depth understanding
+ * of all the possible deadlocks and enospc problems.
+ */
+static long btrfs_ioctl_trans_start(struct file *file)
+{
+ struct inode *inode = fdentry(file)->d_inode;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+ int ret;
+
+ ret = -EPERM;
+ if (!capable(CAP_SYS_ADMIN))
+ goto out;
+
+ ret = -EINPROGRESS;
+ if (file->private_data)
+ goto out;
+
+ ret = -EROFS;
+ if (btrfs_root_readonly(root))
+ goto out;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ goto out;
+
+ atomic_inc(&root->fs_info->open_ioctl_trans);
+
+ ret = -ENOMEM;
+ trans = btrfs_start_ioctl_transaction(root);
+ if (IS_ERR(trans))
+ goto out_drop;
+
+ file->private_data = trans;
+ return 0;
+
+out_drop:
+ atomic_dec(&root->fs_info->open_ioctl_trans);
+ mnt_drop_write_file(file);
+out:
+ return ret;
+}
+
+static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
+{
+ struct inode *inode = fdentry(file)->d_inode;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_root *new_root;
+ struct btrfs_dir_item *di;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_path *path;
+ struct btrfs_key location;
+ struct btrfs_disk_key disk_key;
+ struct btrfs_super_block *disk_super;
+ u64 features;
+ u64 objectid = 0;
+ u64 dir_id;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (copy_from_user(&objectid, argp, sizeof(objectid)))
+ return -EFAULT;
+
+ if (!objectid)
+ objectid = root->root_key.objectid;
+
+ location.objectid = objectid;
+ location.type = BTRFS_ROOT_ITEM_KEY;
+ location.offset = (u64)-1;
+
+ new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
+ if (IS_ERR(new_root))
+ return PTR_ERR(new_root);
+
+ if (btrfs_root_refs(&new_root->root_item) == 0)
+ return -ENOENT;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ path->leave_spinning = 1;
+
+ trans = btrfs_start_transaction(root, 1);
+ if (IS_ERR(trans)) {
+ btrfs_free_path(path);
+ return PTR_ERR(trans);
+ }
+
+ dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
+ di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
+ dir_id, "default", 7, 1);
+ if (IS_ERR_OR_NULL(di)) {
+ btrfs_free_path(path);
+ btrfs_end_transaction(trans, root);
+ printk(KERN_ERR "Umm, you don't have the default dir item, "
+ "this isn't going to work\n");
+ return -ENOENT;
+ }
+
+ btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
+ btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+ btrfs_free_path(path);
+
+ disk_super = root->fs_info->super_copy;
+ features = btrfs_super_incompat_flags(disk_super);
+ if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
+ features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
+ btrfs_set_super_incompat_flags(disk_super, features);
+ }
+ btrfs_end_transaction(trans, root);
+
+ return 0;
+}
+
+static void get_block_group_info(struct list_head *groups_list,
+ struct btrfs_ioctl_space_info *space)
+{
+ struct btrfs_block_group_cache *block_group;
+
+ space->total_bytes = 0;
+ space->used_bytes = 0;
+ space->flags = 0;
+ list_for_each_entry(block_group, groups_list, list) {
+ space->flags = block_group->flags;
+ space->total_bytes += block_group->key.offset;
+ space->used_bytes +=
+ btrfs_block_group_used(&block_group->item);
+ }
+}
+
+long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
+{
+ struct btrfs_ioctl_space_args space_args;
+ struct btrfs_ioctl_space_info space;
+ struct btrfs_ioctl_space_info *dest;
+ struct btrfs_ioctl_space_info *dest_orig;
+ struct btrfs_ioctl_space_info __user *user_dest;
+ struct btrfs_space_info *info;
+ u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
+ BTRFS_BLOCK_GROUP_SYSTEM,
+ BTRFS_BLOCK_GROUP_METADATA,
+ BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
+ int num_types = 4;
+ int alloc_size;
+ int ret = 0;
+ u64 slot_count = 0;
+ int i, c;
+
+ if (copy_from_user(&space_args,
+ (struct btrfs_ioctl_space_args __user *)arg,
+ sizeof(space_args)))
+ return -EFAULT;
+
+ for (i = 0; i < num_types; i++) {
+ struct btrfs_space_info *tmp;
+
+ info = NULL;
+ rcu_read_lock();
+ list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
+ list) {
+ if (tmp->flags == types[i]) {
+ info = tmp;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ if (!info)
+ continue;
+
+ down_read(&info->groups_sem);
+ for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
+ if (!list_empty(&info->block_groups[c]))
+ slot_count++;
+ }
+ up_read(&info->groups_sem);
+ }
+
+ /* space_slots == 0 means they are asking for a count */
+ if (space_args.space_slots == 0) {
+ space_args.total_spaces = slot_count;
+ goto out;
+ }
+
+ slot_count = min_t(u64, space_args.space_slots, slot_count);
+
+ alloc_size = sizeof(*dest) * slot_count;
+
+ /* we generally have at most 6 or so space infos, one for each raid
+ * level. So, a whole page should be more than enough for everyone
+ */
+ if (alloc_size > PAGE_CACHE_SIZE)
+ return -ENOMEM;
+
+ space_args.total_spaces = 0;
+ dest = kmalloc(alloc_size, GFP_NOFS);
+ if (!dest)
+ return -ENOMEM;
+ dest_orig = dest;
+
+ /* now we have a buffer to copy into */
+ for (i = 0; i < num_types; i++) {
+ struct btrfs_space_info *tmp;
+
+ if (!slot_count)
+ break;
+
+ info = NULL;
+ rcu_read_lock();
+ list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
+ list) {
+ if (tmp->flags == types[i]) {
+ info = tmp;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ if (!info)
+ continue;
+ down_read(&info->groups_sem);
+ for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
+ if (!list_empty(&info->block_groups[c])) {
+ get_block_group_info(&info->block_groups[c],
+ &space);
+ memcpy(dest, &space, sizeof(space));
+ dest++;
+ space_args.total_spaces++;
+ slot_count--;
+ }
+ if (!slot_count)
+ break;
+ }
+ up_read(&info->groups_sem);
+ }
+
+ user_dest = (struct btrfs_ioctl_space_info *)
+ (arg + sizeof(struct btrfs_ioctl_space_args));
+
+ if (copy_to_user(user_dest, dest_orig, alloc_size))
+ ret = -EFAULT;
+
+ kfree(dest_orig);
+out:
+ if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
+ ret = -EFAULT;
+
+ return ret;
+}
+
+/*
+ * there are many ways the trans_start and trans_end ioctls can lead
+ * to deadlocks. They should only be used by applications that
+ * basically own the machine, and have a very in depth understanding
+ * of all the possible deadlocks and enospc problems.
+ */
+long btrfs_ioctl_trans_end(struct file *file)
+{
+ struct inode *inode = fdentry(file)->d_inode;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+
+ trans = file->private_data;
+ if (!trans)
+ return -EINVAL;
+ file->private_data = NULL;
+
+ btrfs_end_transaction(trans, root);
+
+ atomic_dec(&root->fs_info->open_ioctl_trans);
+
+ mnt_drop_write_file(file);
+ return 0;
+}
+
+static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
+{
+ struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
+ struct btrfs_trans_handle *trans;
+ u64 transid;
+ int ret;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+ transid = trans->transid;
+ ret = btrfs_commit_transaction_async(trans, root, 0);
+ if (ret) {
+ btrfs_end_transaction(trans, root);
+ return ret;
+ }
+
+ if (argp)
+ if (copy_to_user(argp, &transid, sizeof(transid)))
+ return -EFAULT;
+ return 0;
+}
+
+static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
+{
+ struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
+ u64 transid;
+
+ if (argp) {
+ if (copy_from_user(&transid, argp, sizeof(transid)))
+ return -EFAULT;
+ } else {
+ transid = 0; /* current trans */
+ }
+ return btrfs_wait_for_commit(root, transid);
+}
+
+static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
+{
+ int ret;
+ struct btrfs_ioctl_scrub_args *sa;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa))
+ return PTR_ERR(sa);
+
+ ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
+ &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
+
+ if (copy_to_user(arg, sa, sizeof(*sa)))
+ ret = -EFAULT;
+
+ kfree(sa);
+ return ret;
+}
+
+static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ return btrfs_scrub_cancel(root);
+}
+
+static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
+ void __user *arg)
+{
+ struct btrfs_ioctl_scrub_args *sa;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ sa = memdup_user(arg, sizeof(*sa));
+ if (IS_ERR(sa))
+ return PTR_ERR(sa);
+
+ ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
+
+ if (copy_to_user(arg, sa, sizeof(*sa)))
+ ret = -EFAULT;
+
+ kfree(sa);
+ return ret;
+}
+
+static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
+{
+ int ret = 0;
+ int i;
+ u64 rel_ptr;
+ int size;
+ struct btrfs_ioctl_ino_path_args *ipa = NULL;
+ struct inode_fs_paths *ipath = NULL;
+ struct btrfs_path *path;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ipa = memdup_user(arg, sizeof(*ipa));
+ if (IS_ERR(ipa)) {
+ ret = PTR_ERR(ipa);
+ ipa = NULL;
+ goto out;
+ }
+
+ size = min_t(u32, ipa->size, 4096);
+ ipath = init_ipath(size, root, path);
+ if (IS_ERR(ipath)) {
+ ret = PTR_ERR(ipath);
+ ipath = NULL;
+ goto out;
+ }
+
+ ret = paths_from_inode(ipa->inum, ipath);
+ if (ret < 0)
+ goto out;
+
+ for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
+ rel_ptr = ipath->fspath->val[i] -
+ (u64)(unsigned long)ipath->fspath->val;
+ ipath->fspath->val[i] = rel_ptr;
+ }
+
+ ret = copy_to_user((void *)(unsigned long)ipa->fspath,
+ (void *)(unsigned long)ipath->fspath, size);
+ if (ret) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+out:
+ btrfs_free_path(path);
+ free_ipath(ipath);
+ kfree(ipa);
+
+ return ret;
+}
+
+static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
+{
+ struct btrfs_data_container *inodes = ctx;
+ const size_t c = 3 * sizeof(u64);
+
+ if (inodes->bytes_left >= c) {
+ inodes->bytes_left -= c;
+ inodes->val[inodes->elem_cnt] = inum;
+ inodes->val[inodes->elem_cnt + 1] = offset;
+ inodes->val[inodes->elem_cnt + 2] = root;
+ inodes->elem_cnt += 3;
+ } else {
+ inodes->bytes_missing += c - inodes->bytes_left;
+ inodes->bytes_left = 0;
+ inodes->elem_missed += 3;
+ }
+
+ return 0;
+}
+
+static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
+ void __user *arg)
+{
+ int ret = 0;
+ int size;
+ u64 extent_item_pos;
+ struct btrfs_ioctl_logical_ino_args *loi;
+ struct btrfs_data_container *inodes = NULL;
+ struct btrfs_path *path = NULL;
+ struct btrfs_key key;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ loi = memdup_user(arg, sizeof(*loi));
+ if (IS_ERR(loi)) {
+ ret = PTR_ERR(loi);
+ loi = NULL;
+ goto out;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ size = min_t(u32, loi->size, 4096);
+ inodes = init_data_container(size);
+ if (IS_ERR(inodes)) {
+ ret = PTR_ERR(inodes);
+ inodes = NULL;
+ goto out;
+ }
+
+ ret = extent_from_logical(root->fs_info, loi->logical, path, &key);
+ btrfs_release_path(path);
+
+ if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)
+ ret = -ENOENT;
+ if (ret < 0)
+ goto out;
+
+ extent_item_pos = loi->logical - key.objectid;
+ ret = iterate_extent_inodes(root->fs_info, key.objectid,
+ extent_item_pos, 0, build_ino_list,
+ inodes);
+
+ if (ret < 0)
+ goto out;
+
+ ret = copy_to_user((void *)(unsigned long)loi->inodes,
+ (void *)(unsigned long)inodes, size);
+ if (ret)
+ ret = -EFAULT;
+
+out:
+ btrfs_free_path(path);
+ kfree(inodes);
+ kfree(loi);
+
+ return ret;
+}
+
+void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
+ struct btrfs_ioctl_balance_args *bargs)
+{
+ struct btrfs_balance_control *bctl = fs_info->balance_ctl;
+
+ bargs->flags = bctl->flags;
+
+ if (atomic_read(&fs_info->balance_running))
+ bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
+ if (atomic_read(&fs_info->balance_pause_req))
+ bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
+ if (atomic_read(&fs_info->balance_cancel_req))
+ bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
+
+ memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
+ memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
+ memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
+
+ if (lock) {
+ spin_lock(&fs_info->balance_lock);
+ memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
+ spin_unlock(&fs_info->balance_lock);
+ } else {
+ memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
+ }
+}
+
+static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_ioctl_balance_args *bargs;
+ struct btrfs_balance_control *bctl;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (fs_info->sb->s_flags & MS_RDONLY)
+ return -EROFS;
+
+ mutex_lock(&fs_info->volume_mutex);
+ mutex_lock(&fs_info->balance_mutex);
+
+ if (arg) {
+ bargs = memdup_user(arg, sizeof(*bargs));
+ if (IS_ERR(bargs)) {
+ ret = PTR_ERR(bargs);
+ goto out;
+ }
+
+ if (bargs->flags & BTRFS_BALANCE_RESUME) {
+ if (!fs_info->balance_ctl) {
+ ret = -ENOTCONN;
+ goto out_bargs;
+ }
+
+ bctl = fs_info->balance_ctl;
+ spin_lock(&fs_info->balance_lock);
+ bctl->flags |= BTRFS_BALANCE_RESUME;
+ spin_unlock(&fs_info->balance_lock);
+
+ goto do_balance;
+ }
+ } else {
+ bargs = NULL;
+ }
+
+ if (fs_info->balance_ctl) {
+ ret = -EINPROGRESS;
+ goto out_bargs;
+ }
+
+ bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
+ if (!bctl) {
+ ret = -ENOMEM;
+ goto out_bargs;
+ }
+
+ bctl->fs_info = fs_info;
+ if (arg) {
+ memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
+ memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
+ memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
+
+ bctl->flags = bargs->flags;
+ } else {
+ /* balance everything - no filters */
+ bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
+ }
+
+do_balance:
+ ret = btrfs_balance(bctl, bargs);
+ /*
+ * bctl is freed in __cancel_balance or in free_fs_info if
+ * restriper was paused all the way until unmount
+ */
+ if (arg) {
+ if (copy_to_user(arg, bargs, sizeof(*bargs)))
+ ret = -EFAULT;
+ }
+
+out_bargs:
+ kfree(bargs);
+out:
+ mutex_unlock(&fs_info->balance_mutex);
+ mutex_unlock(&fs_info->volume_mutex);
+ return ret;
+}
+
+static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ switch (cmd) {
+ case BTRFS_BALANCE_CTL_PAUSE:
+ return btrfs_pause_balance(root->fs_info);
+ case BTRFS_BALANCE_CTL_CANCEL:
+ return btrfs_cancel_balance(root->fs_info);
+ }
+
+ return -EINVAL;
+}
+
+static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
+ void __user *arg)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_ioctl_balance_args *bargs;
+ int ret = 0;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ mutex_lock(&fs_info->balance_mutex);
+ if (!fs_info->balance_ctl) {
+ ret = -ENOTCONN;
+ goto out;
+ }
+
+ bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
+ if (!bargs) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ update_ioctl_balance_args(fs_info, 1, bargs);
+
+ if (copy_to_user(arg, bargs, sizeof(*bargs)))
+ ret = -EFAULT;
+
+ kfree(bargs);
+out:
+ mutex_unlock(&fs_info->balance_mutex);
+ return ret;
+}
+
+long btrfs_ioctl(struct file *file, unsigned int
+ cmd, unsigned long arg)
+{
+ struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+ void __user *argp = (void __user *)arg;
+
+ switch (cmd) {
+ case FS_IOC_GETFLAGS:
+ return btrfs_ioctl_getflags(file, argp);
+ case FS_IOC_SETFLAGS:
+ return btrfs_ioctl_setflags(file, argp);
+ case FS_IOC_GETVERSION:
+ return btrfs_ioctl_getversion(file, argp);
+ case FITRIM:
+ return btrfs_ioctl_fitrim(file, argp);
+ case BTRFS_IOC_SNAP_CREATE:
+ return btrfs_ioctl_snap_create(file, argp, 0);
+ case BTRFS_IOC_SNAP_CREATE_V2:
+ return btrfs_ioctl_snap_create_v2(file, argp, 0);
+ case BTRFS_IOC_SUBVOL_CREATE:
+ return btrfs_ioctl_snap_create(file, argp, 1);
+ case BTRFS_IOC_SNAP_DESTROY:
+ return btrfs_ioctl_snap_destroy(file, argp);
+ case BTRFS_IOC_SUBVOL_GETFLAGS:
+ return btrfs_ioctl_subvol_getflags(file, argp);
+ case BTRFS_IOC_SUBVOL_SETFLAGS:
+ return btrfs_ioctl_subvol_setflags(file, argp);
+ case BTRFS_IOC_DEFAULT_SUBVOL:
+ return btrfs_ioctl_default_subvol(file, argp);
+ case BTRFS_IOC_DEFRAG:
+ return btrfs_ioctl_defrag(file, NULL);
+ case BTRFS_IOC_DEFRAG_RANGE:
+ return btrfs_ioctl_defrag(file, argp);
+ case BTRFS_IOC_RESIZE:
+ return btrfs_ioctl_resize(root, argp);
+ case BTRFS_IOC_ADD_DEV:
+ return btrfs_ioctl_add_dev(root, argp);
+ case BTRFS_IOC_RM_DEV:
+ return btrfs_ioctl_rm_dev(root, argp);
+ case BTRFS_IOC_FS_INFO:
+ return btrfs_ioctl_fs_info(root, argp);
+ case BTRFS_IOC_DEV_INFO:
+ return btrfs_ioctl_dev_info(root, argp);
+ case BTRFS_IOC_BALANCE:
+ return btrfs_ioctl_balance(root, NULL);
+ case BTRFS_IOC_CLONE:
+ return btrfs_ioctl_clone(file, arg, 0, 0, 0);
+ case BTRFS_IOC_CLONE_RANGE:
+ return btrfs_ioctl_clone_range(file, argp);
+ case BTRFS_IOC_TRANS_START:
+ return btrfs_ioctl_trans_start(file);
+ case BTRFS_IOC_TRANS_END:
+ return btrfs_ioctl_trans_end(file);
+ case BTRFS_IOC_TREE_SEARCH:
+ return btrfs_ioctl_tree_search(file, argp);
+ case BTRFS_IOC_INO_LOOKUP:
+ return btrfs_ioctl_ino_lookup(file, argp);
+ case BTRFS_IOC_INO_PATHS:
+ return btrfs_ioctl_ino_to_path(root, argp);
+ case BTRFS_IOC_LOGICAL_INO:
+ return btrfs_ioctl_logical_to_ino(root, argp);
+ case BTRFS_IOC_SPACE_INFO:
+ return btrfs_ioctl_space_info(root, argp);
+ case BTRFS_IOC_SYNC:
+ btrfs_sync_fs(file->f_dentry->d_sb, 1);
+ return 0;
+ case BTRFS_IOC_START_SYNC:
+ return btrfs_ioctl_start_sync(file, argp);
+ case BTRFS_IOC_WAIT_SYNC:
+ return btrfs_ioctl_wait_sync(file, argp);
+ case BTRFS_IOC_SCRUB:
+ return btrfs_ioctl_scrub(root, argp);
+ case BTRFS_IOC_SCRUB_CANCEL:
+ return btrfs_ioctl_scrub_cancel(root, argp);
+ case BTRFS_IOC_SCRUB_PROGRESS:
+ return btrfs_ioctl_scrub_progress(root, argp);
+ case BTRFS_IOC_BALANCE_V2:
+ return btrfs_ioctl_balance(root, argp);
+ case BTRFS_IOC_BALANCE_CTL:
+ return btrfs_ioctl_balance_ctl(root, arg);
+ case BTRFS_IOC_BALANCE_PROGRESS:
+ return btrfs_ioctl_balance_progress(root, argp);
+ }
+
+ return -ENOTTY;
+}