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linux/fs/btrfs/ioctl.c
Christoph Hellwig 04b38d6012 vfs: pull btrfs clone API to vfs layer 
The btrfs clone ioctls are now adopted by other file systems, with NFS
and CIFS already having support for them, and XFS being under active
development.  To avoid growth of various slightly incompatible
implementations, add one to the VFS.  Note that clones are different from
file copies in several ways:

 - they are atomic vs other writers
 - they support whole file clones
 - they support 64-bit legth clones
 - they do not allow partial success (aka short writes)
 - clones are expected to be a fast metadata operation

Because of that it would be rather cumbersome to try to piggyback them on
top of the recent clone_file_range infrastructure.  The converse isn't
true and the clone_file_range system call could try clone file range as
a first attempt to copy, something that further patches will enable.

Based on earlier work from Peng Tao.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-07 23:11:33 -05:00

5551 lines
135 KiB
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/*
* 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 <linux/btrfs.h>
#include <linux/uaccess.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "btrfs_inode.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"
#include "dev-replace.h"
#include "props.h"
#include "sysfs.h"
#include "qgroup.h"
#ifdef CONFIG_64BIT
/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
* structures are incorrect, as the timespec structure from userspace
* is 4 bytes too small. We define these alternatives here to teach
* the kernel about the 32-bit struct packing.
*/
struct btrfs_ioctl_timespec_32 {
__u64 sec;
__u32 nsec;
} __attribute__ ((__packed__));
struct btrfs_ioctl_received_subvol_args_32 {
char uuid[BTRFS_UUID_SIZE]; /* in */
__u64 stransid; /* in */
__u64 rtransid; /* out */
struct btrfs_ioctl_timespec_32 stime; /* in */
struct btrfs_ioctl_timespec_32 rtime; /* out */
__u64 flags; /* in */
__u64 reserved[16]; /* in */
} __attribute__ ((__packed__));
#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
struct btrfs_ioctl_received_subvol_args_32)
#endif
static int btrfs_clone(struct inode *src, struct inode *inode,
u64 off, u64 olen, u64 olen_aligned, u64 destoff,
int no_time_update);
/* 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);
unsigned int new_fl = 0;
if (ip->flags & BTRFS_INODE_SYNC)
new_fl |= S_SYNC;
if (ip->flags & BTRFS_INODE_IMMUTABLE)
new_fl |= S_IMMUTABLE;
if (ip->flags & BTRFS_INODE_APPEND)
new_fl |= S_APPEND;
if (ip->flags & BTRFS_INODE_NOATIME)
new_fl |= S_NOATIME;
if (ip->flags & BTRFS_INODE_DIRSYNC)
new_fl |= S_DIRSYNC;
set_mask_bits(&inode->i_flags,
S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
new_fl);
}
/*
* 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;
if (S_ISREG(inode->i_mode))
BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
}
btrfs_update_iflags(inode);
}
static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
{
struct btrfs_inode *ip = BTRFS_I(file_inode(file));
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_inode(file);
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;
umode_t mode;
if (!inode_owner_or_capable(inode))
return -EPERM;
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;
ret = mnt_want_write_file(file);
if (ret)
return ret;
mutex_lock(&inode->i_mutex);
ip_oldflags = ip->flags;
i_oldflags = inode->i_flags;
mode = inode->i_mode;
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) {
if (S_ISREG(mode)) {
/*
* It's safe to turn csums off here, no extents exist.
* Otherwise we want the flag to reflect the real COW
* status of the file and will not set it.
*/
if (inode->i_size == 0)
ip->flags |= BTRFS_INODE_NODATACOW
| BTRFS_INODE_NODATASUM;
} else {
ip->flags |= BTRFS_INODE_NODATACOW;
}
} else {
/*
* Revert back under same assuptions as above
*/
if (S_ISREG(mode)) {
if (inode->i_size == 0)
ip->flags &= ~(BTRFS_INODE_NODATACOW
| BTRFS_INODE_NODATASUM);
} 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;
ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
if (ret && ret != -ENODATA)
goto out_drop;
} else if (flags & FS_COMPR_FL) {
const char *comp;
ip->flags |= BTRFS_INODE_COMPRESS;
ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
comp = "lzo";
else
comp = "zlib";
ret = btrfs_set_prop(inode, "btrfs.compression",
comp, strlen(comp), 0);
if (ret)
goto out_drop;
} else {
ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
if (ret && ret != -ENODATA)
goto out_drop;
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_inode(file);
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(file_inode(file)->i_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 ||
range.len < fs_info->sb->s_blocksize)
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;
}
int btrfs_is_empty_uuid(u8 *uuid)
{
int i;
for (i = 0; i < BTRFS_UUID_SIZE; i++) {
if (uuid[i])
return 0;
}
return 1;
}
static noinline int create_subvol(struct inode *dir,
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 *root = BTRFS_I(dir)->root;
struct btrfs_root *new_root;
struct btrfs_block_rsv block_rsv;
struct timespec cur_time = CURRENT_TIME;
struct inode *inode;
int ret;
int err;
u64 objectid;
u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
u64 index = 0;
u64 qgroup_reserved;
uuid_le new_uuid;
ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
if (ret)
return ret;
/*
* Don't create subvolume whose level is not zero. Or qgroup will be
* screwed up since it assume subvolme qgroup's level to be 0.
*/
if (btrfs_qgroup_level(objectid))
return -ENOSPC;
btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
/*
* The same as the snapshot creation, please see the comment
* of create_snapshot().
*/
ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
8, &qgroup_reserved, false);
if (ret)
return ret;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
btrfs_subvolume_release_metadata(root, &block_rsv,
qgroup_reserved);
return ret;
}
trans->block_rsv = &block_rsv;
trans->bytes_reserved = block_rsv.size;
ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
if (ret)
goto fail;
leaf = btrfs_alloc_tree_block(trans, root, 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, btrfs_header_fsid(),
BTRFS_FSID_SIZE);
write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
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;
btrfs_set_stack_inode_generation(inode_item, 1);
btrfs_set_stack_inode_size(inode_item, 3);
btrfs_set_stack_inode_nlink(inode_item, 1);
btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
btrfs_set_root_flags(&root_item, 0);
btrfs_set_root_limit(&root_item, 0);
btrfs_set_stack_inode_flags(inode_item, 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);
btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
btrfs_set_stack_timespec_nsec(&root_item.otime, 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;
key.type = 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)) {
ret = PTR_ERR(new_root);
btrfs_abort_transaction(trans, root, ret);
goto fail;
}
btrfs_record_root_in_trans(trans, new_root);
ret = btrfs_create_subvol_root(trans, new_root, 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);
ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
objectid);
if (ret)
btrfs_abort_transaction(trans, root, ret);
fail:
trans->block_rsv = NULL;
trans->bytes_reserved = 0;
btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
if (async_transid) {
*async_transid = trans->transid;
err = btrfs_commit_transaction_async(trans, root, 1);
if (err)
err = btrfs_commit_transaction(trans, root);
} else {
err = btrfs_commit_transaction(trans, root);
}
if (err && !ret)
ret = err;
if (!ret) {
inode = btrfs_lookup_dentry(dir, dentry);
if (IS_ERR(inode))
return PTR_ERR(inode);
d_instantiate(dentry, inode);
}
return ret;
}
static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
{
s64 writers;
DEFINE_WAIT(wait);
do {
prepare_to_wait(&root->subv_writers->wait, &wait,
TASK_UNINTERRUPTIBLE);
writers = percpu_counter_sum(&root->subv_writers->counter);
if (writers)
schedule();
finish_wait(&root->subv_writers->wait, &wait);
} while (writers);
}
static int create_snapshot(struct btrfs_root *root, struct inode *dir,
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 (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
return -EINVAL;
atomic_inc(&root->will_be_snapshoted);
smp_mb__after_atomic();
btrfs_wait_for_no_snapshoting_writes(root);
ret = btrfs_start_delalloc_inodes(root, 0);
if (ret)
goto out;
btrfs_wait_ordered_extents(root, -1);
pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
if (!pending_snapshot) {
ret = -ENOMEM;
goto out;
}
btrfs_init_block_rsv(&pending_snapshot->block_rsv,
BTRFS_BLOCK_RSV_TEMP);
/*
* 1 - parent dir inode
* 2 - dir entries
* 1 - root item
* 2 - root ref/backref
* 1 - root of snapshot
* 1 - UUID item
*/
ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
&pending_snapshot->block_rsv, 8,
&pending_snapshot->qgroup_reserved,
false);
if (ret)
goto free;
pending_snapshot->dentry = dentry;
pending_snapshot->root = root;
pending_snapshot->readonly = readonly;
pending_snapshot->dir = dir;
pending_snapshot->inherit = inherit;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto fail;
}
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);
if (ret)
ret = btrfs_commit_transaction(trans, root);
} else {
ret = btrfs_commit_transaction(trans,
root->fs_info->extent_root);
}
if (ret)
goto fail;
ret = pending_snapshot->error;
if (ret)
goto fail;
ret = btrfs_orphan_cleanup(pending_snapshot->snap);
if (ret)
goto fail;
inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
if (IS_ERR(inode)) {
ret = PTR_ERR(inode);
goto fail;
}
d_instantiate(dentry, inode);
ret = 0;
fail:
btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
&pending_snapshot->block_rsv,
pending_snapshot->qgroup_reserved);
free:
kfree(pending_snapshot);
out:
if (atomic_dec_and_test(&root->will_be_snapshoted))
wake_up_atomic_t(&root->will_be_snapshoted);
return ret;
}
/* 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 (d_really_is_negative(victim))
return -ENOENT;
BUG_ON(d_inode(victim->d_parent) != dir);
audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
if (error)
return error;
if (IS_APPEND(dir))
return -EPERM;
if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
return -EPERM;
if (isdir) {
if (!d_is_dir(victim))
return -ENOTDIR;
if (IS_ROOT(victim))
return -EBUSY;
} else if (d_is_dir(victim))
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 (d_really_is_positive(child))
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 = d_inode(parent->dentry);
struct dentry *dentry;
int error;
error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
if (error == -EINTR)
return error;
dentry = lookup_one_len(name, parent->dentry, namelen);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto out_unlock;
error = -EEXIST;
if (d_really_is_positive(dentry))
goto out_dput;
error = btrfs_may_create(dir, dentry);
if (error)
goto out_dput;
/*
* even if this name doesn't exist, we may get hash collisions.
* check for them now when we can safely fail
*/
error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
dir->i_ino, name,
namelen);
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, dir, dentry, name, namelen,
async_transid, readonly, inherit);
} else {
error = create_subvol(dir, 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, u32 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, u32 thresh)
{
struct btrfs_path *path;
struct btrfs_key min_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;
while (1) {
ret = btrfs_search_forward(root, &min_key, path, newer_than);
if (ret != 0)
goto none;
process_slot:
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;
}
path->slots[0]++;
if (path->slots[0] < btrfs_header_nritems(leaf)) {
btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
goto process_slot;
}
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) {
struct extent_state *cached = NULL;
u64 end = start + len - 1;
/* get the big lock and read metadata off disk */
lock_extent_bits(io_tree, start, end, 0, &cached);
em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
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;
else if ((em->block_start + em->block_len == next->block_start) &&
(em->block_len > 128 * 1024 && next->block_len > 128 * 1024))
ret = false;
free_extent_map(next);
return ret;
}
static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
u64 *last_len, u64 *skip, u64 *defrag_end,
int compress)
{
struct extent_map *em;
int ret = 1;
bool next_mergeable = true;
bool prev_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;
}
if (!*defrag_end)
prev_mergeable = false;
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 && !prev_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,
unsigned long 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,
start_index << PAGE_CACHE_SHIFT,
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_bits(tree, page_start, page_end,
0, &cached_state);
ordered = btrfs_lookup_ordered_extent(inode,
page_start);
unlock_extent_cached(tree, page_start, page_end,
&cached_state, GFP_NOFS);
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 | EXTENT_DEFRAG, 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,
start_index << PAGE_CACHE_SHIFT,
(page_cnt - i_done) << PAGE_CACHE_SHIFT);
}
set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
&cached_state, GFP_NOFS);
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,
start_index << PAGE_CACHE_SHIFT,
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;
u32 extent_thresh = range->extent_thresh;
unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
unsigned long cluster = max_cluster;
u64 new_align = ~((u64)128 * 1024 - 1);
struct page **pages = NULL;
if (isize == 0)
return 0;
if (range->start >= isize)
return -EINVAL;
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 (extent_thresh == 0)
extent_thresh = 256 * 1024;
/*
* 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_array(max_cluster, sizeof(struct page *),
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 - i + 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 < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) {
/*
* make sure we stop running if someone unmounts
* the FS
*/
if (!(inode->i_sb->s_flags & MS_ACTIVE))
break;
if (btrfs_defrag_cancelled(root->fs_info)) {
btrfs_debug(root->fs_info, "defrag_file cancelled");
ret = -EAGAIN;
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 = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE);
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 (i + cluster > ra_index) {
ra_index = max(i, ra_index);
btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
cluster);
ra_index += cluster;
}
mutex_lock(&inode->i_mutex);
if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
BTRFS_I(inode)->force_compress = compress_type;
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(inode->i_mapping);
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 (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
&BTRFS_I(inode)->runtime_flags))
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);
}
if (range->compress_type == BTRFS_COMPRESS_LZO) {
btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
}
ret = defrag_count;
out_ra:
if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
mutex_lock(&inode->i_mutex);
BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
mutex_unlock(&inode->i_mutex);
}
if (!file)
kfree(ra);
kfree(pages);
return ret;
}
static noinline int btrfs_ioctl_resize(struct file *file,
void __user *arg)
{
u64 new_size;
u64 old_size;
u64 devid = 1;
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_ioctl_vol_args *vol_args;
struct btrfs_trans_handle *trans;
struct btrfs_device *device = NULL;
char *sizestr;
char *retptr;
char *devstr = NULL;
int ret = 0;
int mod = 0;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1)) {
mnt_drop_write_file(file);
return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
}
mutex_lock(&root->fs_info->volume_mutex);
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) {
sizestr = devstr + 1;
*devstr = '\0';
devstr = vol_args->name;
ret = kstrtoull(devstr, 10, &devid);
if (ret)
goto out_free;
if (!devid) {
ret = -EINVAL;
goto out_free;
}
btrfs_info(root->fs_info, "resizing devid %llu", devid);
}
device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
if (!device) {
btrfs_info(root->fs_info, "resizer unable to find device %llu",
devid);
ret = -ENODEV;
goto out_free;
}
if (!device->writeable) {
btrfs_info(root->fs_info,
"resizer unable to apply on readonly device %llu",
devid);
ret = -EPERM;
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, &retptr);
if (*retptr != '\0' || new_size == 0) {
ret = -EINVAL;
goto out_free;
}
}
if (device->is_tgtdev_for_dev_replace) {
ret = -EPERM;
goto out_free;
}
old_size = btrfs_device_get_total_bytes(device);
if (mod < 0) {
if (new_size > old_size) {
ret = -EINVAL;
goto out_free;
}
new_size = old_size - new_size;
} else if (mod > 0) {
if (new_size > ULLONG_MAX - old_size) {
ret = -ERANGE;
goto out_free;
}
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;
}
new_size = div_u64(new_size, root->sectorsize);
new_size *= root->sectorsize;
btrfs_info_in_rcu(root->fs_info, "new size for %s is %llu",
rcu_str_deref(device->name), 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);
} /* equal, nothing need to do */
out_free:
kfree(vol_args);
out:
mutex_unlock(&root->fs_info->volume_mutex);
atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
mnt_drop_write_file(file);
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)
{
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 fd src = fdget(fd);
struct inode *src_inode;
if (!src.file) {
ret = -EINVAL;
goto out_drop_write;
}
src_inode = file_inode(src.file);
if (src_inode->i_sb != file_inode(file)->i_sb) {
btrfs_info(BTRFS_I(src_inode)->root->fs_info,
"Snapshot src from another FS");
ret = -EXDEV;
} else if (!inode_owner_or_capable(src_inode)) {
/*
* Subvolume creation is not restricted, but snapshots
* are limited to own subvolumes only
*/
ret = -EPERM;
} else {
ret = btrfs_mksubvol(&file->f_path, name, namelen,
BTRFS_I(src_inode)->root,
transid, readonly, inherit);
}
fdput(src);
}
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 free_args;
}
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 free_args;
}
inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
if (IS_ERR(inherit)) {
ret = PTR_ERR(inherit);
goto free_args;
}
}
ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
vol_args->fd, subvol, ptr,
readonly, inherit);
if (ret)
goto free_inherit;
if (ptr && copy_to_user(arg +
offsetof(struct btrfs_ioctl_vol_args_v2,
transid),
ptr, sizeof(*ptr)))
ret = -EFAULT;
free_inherit:
kfree(inherit);
free_args:
kfree(vol_args);
return ret;
}
static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
void __user *arg)
{
struct inode *inode = file_inode(file);
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 = file_inode(file);
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_trans_handle *trans;
u64 root_flags;
u64 flags;
int ret = 0;
if (!inode_owner_or_capable(inode))
return -EPERM;
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;
}
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 {
/*
* Block RO -> RW transition if this subvolume is involved in
* send
*/
spin_lock(&root->root_item_lock);
if (root->send_in_progress == 0) {
btrfs_set_root_flags(&root->root_item,
root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
spin_unlock(&root->root_item_lock);
} else {
spin_unlock(&root->root_item_lock);
btrfs_warn(root->fs_info,
"Attempt to set subvolume %llu read-write during send",
root->root_key.objectid);
ret = -EPERM;
goto out_drop_sem;
}
}
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_dir_item *di;
struct btrfs_key key;
u64 dir_id;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
/* Make sure this root isn't set as the default subvol */
dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
dir_id, "default", 7, 0);
if (di && !IS_ERR(di)) {
btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
if (key.objectid == root->root_key.objectid) {
ret = -EPERM;
btrfs_err(root->fs_info, "deleting default subvolume "
"%llu is not allowed", key.objectid);
goto out;
}
btrfs_release_path(path);
}
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,
size_t *buf_size,
char __user *ubuf,
unsigned long *sk_offset,
int *num_found)
{
u64 found_transid;
struct extent_buffer *leaf;
struct btrfs_ioctl_search_header sh;
struct btrfs_key test;
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 > *buf_size) {
if (*num_found) {
ret = 1;
goto out;
}
/*
* return one empty item back for v1, which does not
* handle -EOVERFLOW
*/
*buf_size = sizeof(sh) + item_len;
item_len = 0;
ret = -EOVERFLOW;
}
if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
ret = 1;
goto out;
}
sh.objectid = key->objectid;
sh.offset = key->offset;
sh.type = key->type;
sh.len = item_len;
sh.transid = found_transid;
/* copy search result header */
if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
ret = -EFAULT;
goto out;
}
*sk_offset += sizeof(sh);
if (item_len) {
char __user *up = ubuf + *sk_offset;
/* copy the item */
if (read_extent_buffer_to_user(leaf, up,
item_off, item_len)) {
ret = -EFAULT;
goto out;
}
*sk_offset += item_len;
}
(*num_found)++;
if (ret) /* -EOVERFLOW from above */
goto out;
if (*num_found >= sk->nr_items) {
ret = 1;
goto out;
}
}
advance_key:
ret = 0;
test.objectid = sk->max_objectid;
test.type = sk->max_type;
test.offset = sk->max_offset;
if (btrfs_comp_cpu_keys(key, &test) >= 0)
ret = 1;
else if (key->offset < (u64)-1)
key->offset++;
else if (key->type < (u8)-1) {
key->offset = 0;
key->type++;
} else if (key->objectid < (u64)-1) {
key->offset = 0;
key->type = 0;
key->objectid++;
} else
ret = 1;
out:
/*
* 0: all items from this leaf copied, continue with next
* 1: * more items can be copied, but unused buffer is too small
* * all items were found
* Either way, it will stops the loop which iterates to the next
* leaf
* -EOVERFLOW: item was to large for buffer
* -EFAULT: could not copy extent buffer back to userspace
*/
return ret;
}
static noinline int search_ioctl(struct inode *inode,
struct btrfs_ioctl_search_key *sk,
size_t *buf_size,
char __user *ubuf)
{
struct btrfs_root *root;
struct btrfs_key key;
struct btrfs_path *path;
struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
int ret;
int num_found = 0;
unsigned long sk_offset = 0;
if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
*buf_size = sizeof(struct btrfs_ioctl_search_header);
return -EOVERFLOW;
}
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)) {
btrfs_err(info, "could not find root %llu",
sk->tree_id);
btrfs_free_path(path);
return -ENOENT;
}
}
key.objectid = sk->min_objectid;
key.type = sk->min_type;
key.offset = sk->min_offset;
while (1) {
ret = btrfs_search_forward(root, &key, path, sk->min_transid);
if (ret != 0) {
if (ret > 0)
ret = 0;
goto err;
}
ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
&sk_offset, &num_found);
btrfs_release_path(path);
if (ret)
break;
}
if (ret > 0)
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 __user *uargs;
struct btrfs_ioctl_search_key sk;
struct inode *inode;
int ret;
size_t buf_size;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
uargs = (struct btrfs_ioctl_search_args __user *)argp;
if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
return -EFAULT;
buf_size = sizeof(uargs->buf);
inode = file_inode(file);
ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
/*
* In the origin implementation an overflow is handled by returning a
* search header with a len of zero, so reset ret.
*/
if (ret == -EOVERFLOW)
ret = 0;
if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
ret = -EFAULT;
return ret;
}
static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
void __user *argp)
{
struct btrfs_ioctl_search_args_v2 __user *uarg;
struct btrfs_ioctl_search_args_v2 args;
struct inode *inode;
int ret;
size_t buf_size;
const size_t buf_limit = 16 * 1024 * 1024;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
/* copy search header and buffer size */
uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
if (copy_from_user(&args, uarg, sizeof(args)))
return -EFAULT;
buf_size = args.buf_size;
if (buf_size < sizeof(struct btrfs_ioctl_search_header))
return -EOVERFLOW;
/* limit result size to 16MB */
if (buf_size > buf_limit)
buf_size = buf_limit;
inode = file_inode(file);
ret = search_ioctl(inode, &args.key, &buf_size,
(char *)(&uarg->buf[0]));
if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
ret = -EFAULT;
else if (ret == -EOVERFLOW &&
copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
ret = -EFAULT;
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)) {
btrfs_err(info, "could not find root %llu", 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;
else if (ret > 0) {
ret = btrfs_previous_item(root, path, dirid,
BTRFS_INODE_REF_KEY);
if (ret < 0)
goto out;
else if (ret > 0) {
ret = -ENOENT;
goto out;
}
}
l = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(l, &key, slot);
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) {
ret = -ENAMETOOLONG;
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;
}
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 = 0;
args = memdup_user(argp, sizeof(*args));
if (IS_ERR(args))
return PTR_ERR(args);
inode = file_inode(file);
/*
* Unprivileged query to obtain the containing subvolume root id. The
* path is reset so it's consistent with btrfs_search_path_in_tree.
*/
if (args->treeid == 0)
args->treeid = BTRFS_I(inode)->root->root_key.objectid;
if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
args->name[0] = 0;
goto out;
}
if (!capable(CAP_SYS_ADMIN)) {
ret = -EPERM;
goto out;
}
ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
args->treeid, args->objectid,
args->name);
out:
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 = file->f_path.dentry;
struct dentry *dentry;
struct inode *dir = d_inode(parent);
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;
struct btrfs_block_rsv block_rsv;
u64 root_flags;
u64 qgroup_reserved;
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;
err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
if (err == -EINTR)
goto out_drop_write;
dentry = lookup_one_len(vol_args->name, parent, namelen);
if (IS_ERR(dentry)) {
err = PTR_ERR(dentry);
goto out_unlock_dir;
}
if (d_really_is_negative(dentry)) {
err = -ENOENT;
goto out_dput;
}
inode = d_inode(dentry);
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 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);
/*
* Don't allow to delete a subvolume with send in progress. This is
* inside the i_mutex so the error handling that has to drop the bit
* again is not run concurrently.
*/
spin_lock(&dest->root_item_lock);
root_flags = btrfs_root_flags(&dest->root_item);
if (dest->send_in_progress == 0) {
btrfs_set_root_flags(&dest->root_item,
root_flags | BTRFS_ROOT_SUBVOL_DEAD);
spin_unlock(&dest->root_item_lock);
} else {
spin_unlock(&dest->root_item_lock);
btrfs_warn(root->fs_info,
"Attempt to delete subvolume %llu during send",
dest->root_key.objectid);
err = -EPERM;
goto out_unlock_inode;
}
down_write(&root->fs_info->subvol_sem);
err = may_destroy_subvol(dest);
if (err)
goto out_up_write;
btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
/*
* One for dir inode, two for dir entries, two for root
* ref/backref.
*/
err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
5, &qgroup_reserved, true);
if (err)
goto out_up_write;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
err = PTR_ERR(trans);
goto out_release;
}
trans->block_rsv = &block_rsv;
trans->bytes_reserved = block_rsv.size;
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 (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
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;
}
}
ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
dest->root_key.objectid);
if (ret && ret != -ENOENT) {
btrfs_abort_transaction(trans, root, ret);
err = ret;
goto out_end_trans;
}
if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
dest->root_item.received_uuid,
BTRFS_UUID_KEY_RECEIVED_SUBVOL,
dest->root_key.objectid);
if (ret && ret != -ENOENT) {
btrfs_abort_transaction(trans, root, ret);
err = ret;
goto out_end_trans;
}
}
out_end_trans:
trans->block_rsv = NULL;
trans->bytes_reserved = 0;
ret = btrfs_end_transaction(trans, root);
if (ret && !err)
err = ret;
inode->i_flags |= S_DEAD;
out_release:
btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
out_up_write:
up_write(&root->fs_info->subvol_sem);
if (err) {
spin_lock(&dest->root_item_lock);
root_flags = btrfs_root_flags(&dest->root_item);
btrfs_set_root_flags(&dest->root_item,
root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
spin_unlock(&dest->root_item_lock);
}
out_unlock_inode:
mutex_unlock(&inode->i_mutex);
if (!err) {
d_invalidate(dentry);
btrfs_invalidate_inodes(dest);
d_delete(dentry);
ASSERT(dest->send_in_progress == 0);
/* the last ref */
if (dest->ino_cache_inode) {
iput(dest->ino_cache_inode);
dest->ino_cache_inode = NULL;
}
}
out_dput:
dput(dentry);
out_unlock_dir:
mutex_unlock(&dir->i_mutex);
out_drop_write:
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 = file_inode(file);
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_ioctl_defrag_range_args *range;
int ret;
ret = mnt_want_write_file(file);
if (ret)
return ret;
if (btrfs_root_readonly(root)) {
ret = -EROFS;
goto out;
}
switch (inode->i_mode & S_IFMT) {
case S_IFDIR:
if (!capable(CAP_SYS_ADMIN)) {
ret = -EPERM;
goto out;
}
ret = btrfs_defrag_root(root);
if (ret)
goto out;
ret = btrfs_defrag_root(root->fs_info->extent_root);
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(file_inode(file), 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;
if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1)) {
return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
}
mutex_lock(&root->fs_info->volume_mutex);
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);
if (!ret)
btrfs_info(root->fs_info, "disk added %s",vol_args->name);
kfree(vol_args);
out:
mutex_unlock(&root->fs_info->volume_mutex);
atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
return ret;
}
static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_ioctl_vol_args *vol_args;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
vol_args = memdup_user(arg, sizeof(*vol_args));
if (IS_ERR(vol_args)) {
ret = PTR_ERR(vol_args);
goto err_drop;
}
vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1)) {
ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
goto out;
}
mutex_lock(&root->fs_info->volume_mutex);
ret = btrfs_rm_device(root, vol_args->name);
mutex_unlock(&root->fs_info->volume_mutex);
atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
if (!ret)
btrfs_info(root->fs_info, "disk deleted %s",vol_args->name);
out:
kfree(vol_args);
err_drop:
mnt_drop_write_file(file);
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_fs_devices *fs_devices = root->fs_info->fs_devices;
int ret = 0;
fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
if (!fi_args)
return -ENOMEM;
mutex_lock(&fs_devices->device_list_mutex);
fi_args->num_devices = fs_devices->num_devices;
memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
list_for_each_entry(device, &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);
fi_args->nodesize = root->fs_info->super_copy->nodesize;
fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
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;
di_args = memdup_user(arg, sizeof(*di_args));
if (IS_ERR(di_args))
return PTR_ERR(di_args);
if (!btrfs_is_empty_uuid(di_args->uuid))
s_uuid = di_args->uuid;
mutex_lock(&fs_devices->device_list_mutex);
dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
if (!dev) {
ret = -ENODEV;
goto out;
}
di_args->devid = dev->devid;
di_args->bytes_used = btrfs_device_get_bytes_used(dev);
di_args->total_bytes = btrfs_device_get_total_bytes(dev);
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:
mutex_unlock(&fs_devices->device_list_mutex);
if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
ret = -EFAULT;
kfree(di_args);
return ret;
}
static struct page *extent_same_get_page(struct inode *inode, pgoff_t index)
{
struct page *page;
struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
page = grab_cache_page(inode->i_mapping, index);
if (!page)
return NULL;
if (!PageUptodate(page)) {
if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
0))
return NULL;
lock_page(page);
if (!PageUptodate(page)) {
unlock_page(page);
page_cache_release(page);
return NULL;
}
}
unlock_page(page);
return page;
}
static int gather_extent_pages(struct inode *inode, struct page **pages,
int num_pages, u64 off)
{
int i;
pgoff_t index = off >> PAGE_CACHE_SHIFT;
for (i = 0; i < num_pages; i++) {
pages[i] = extent_same_get_page(inode, index + i);
if (!pages[i])
return -ENOMEM;
}
return 0;
}
static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
{
/* do any pending delalloc/csum calc on src, one way or
another, and lock file content */
while (1) {
struct btrfs_ordered_extent *ordered;
lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
ordered = btrfs_lookup_first_ordered_extent(inode,
off + len - 1);
if ((!ordered ||
ordered->file_offset + ordered->len <= off ||
ordered->file_offset >= off + len) &&
!test_range_bit(&BTRFS_I(inode)->io_tree, off,
off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
if (ordered)
btrfs_put_ordered_extent(ordered);
break;
}
unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
if (ordered)
btrfs_put_ordered_extent(ordered);
btrfs_wait_ordered_range(inode, off, len);
}
}
static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2)
{
mutex_unlock(&inode1->i_mutex);
mutex_unlock(&inode2->i_mutex);
}
static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
{
if (inode1 < inode2)
swap(inode1, inode2);
mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
}
static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
struct inode *inode2, u64 loff2, u64 len)
{
unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
}
static void btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
struct inode *inode2, u64 loff2, u64 len)
{
if (inode1 < inode2) {
swap(inode1, inode2);
swap(loff1, loff2);
}
lock_extent_range(inode1, loff1, len);
lock_extent_range(inode2, loff2, len);
}
struct cmp_pages {
int num_pages;
struct page **src_pages;
struct page **dst_pages;
};
static void btrfs_cmp_data_free(struct cmp_pages *cmp)
{
int i;
struct page *pg;
for (i = 0; i < cmp->num_pages; i++) {
pg = cmp->src_pages[i];
if (pg)
page_cache_release(pg);
pg = cmp->dst_pages[i];
if (pg)
page_cache_release(pg);
}
kfree(cmp->src_pages);
kfree(cmp->dst_pages);
}
static int btrfs_cmp_data_prepare(struct inode *src, u64 loff,
struct inode *dst, u64 dst_loff,
u64 len, struct cmp_pages *cmp)
{
int ret;
int num_pages = PAGE_CACHE_ALIGN(len) >> PAGE_CACHE_SHIFT;
struct page **src_pgarr, **dst_pgarr;
/*
* We must gather up all the pages before we initiate our
* extent locking. We use an array for the page pointers. Size
* of the array is bounded by len, which is in turn bounded by
* BTRFS_MAX_DEDUPE_LEN.
*/
src_pgarr = kzalloc(num_pages * sizeof(struct page *), GFP_NOFS);
dst_pgarr = kzalloc(num_pages * sizeof(struct page *), GFP_NOFS);
if (!src_pgarr || !dst_pgarr) {
kfree(src_pgarr);
kfree(dst_pgarr);
return -ENOMEM;
}
cmp->num_pages = num_pages;
cmp->src_pages = src_pgarr;
cmp->dst_pages = dst_pgarr;
ret = gather_extent_pages(src, cmp->src_pages, cmp->num_pages, loff);
if (ret)
goto out;
ret = gather_extent_pages(dst, cmp->dst_pages, cmp->num_pages, dst_loff);
out:
if (ret)
btrfs_cmp_data_free(cmp);
return 0;
}
static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
u64 dst_loff, u64 len, struct cmp_pages *cmp)
{
int ret = 0;
int i;
struct page *src_page, *dst_page;
unsigned int cmp_len = PAGE_CACHE_SIZE;
void *addr, *dst_addr;
i = 0;
while (len) {
if (len < PAGE_CACHE_SIZE)
cmp_len = len;
BUG_ON(i >= cmp->num_pages);
src_page = cmp->src_pages[i];
dst_page = cmp->dst_pages[i];
addr = kmap_atomic(src_page);
dst_addr = kmap_atomic(dst_page);
flush_dcache_page(src_page);
flush_dcache_page(dst_page);
if (memcmp(addr, dst_addr, cmp_len))
ret = BTRFS_SAME_DATA_DIFFERS;
kunmap_atomic(addr);
kunmap_atomic(dst_addr);
if (ret)
break;
len -= cmp_len;
i++;
}
return ret;
}
static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen,
u64 olen)
{
u64 len = *plen;
u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
if (off + olen > inode->i_size || off + olen < off)
return -EINVAL;
/* if we extend to eof, continue to block boundary */
if (off + len == inode->i_size)
*plen = len = ALIGN(inode->i_size, bs) - off;
/* Check that we are block aligned - btrfs_clone() requires this */
if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
return -EINVAL;
return 0;
}
static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
struct inode *dst, u64 dst_loff)
{
int ret;
u64 len = olen;
struct cmp_pages cmp;
int same_inode = 0;
u64 same_lock_start = 0;
u64 same_lock_len = 0;
if (src == dst)
same_inode = 1;
if (len == 0)
return 0;
if (same_inode) {
mutex_lock(&src->i_mutex);
ret = extent_same_check_offsets(src, loff, &len, olen);
if (ret)
goto out_unlock;
/*
* Single inode case wants the same checks, except we
* don't want our length pushed out past i_size as
* comparing that data range makes no sense.
*
* extent_same_check_offsets() will do this for an
* unaligned length at i_size, so catch it here and
* reject the request.
*
* This effectively means we require aligned extents
* for the single-inode case, whereas the other cases
* allow an unaligned length so long as it ends at
* i_size.
*/
if (len != olen) {
ret = -EINVAL;
goto out_unlock;
}
/* Check for overlapping ranges */
if (dst_loff + len > loff && dst_loff < loff + len) {
ret = -EINVAL;
goto out_unlock;
}
same_lock_start = min_t(u64, loff, dst_loff);
same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start;
} else {
btrfs_double_inode_lock(src, dst);
ret = extent_same_check_offsets(src, loff, &len, olen);
if (ret)
goto out_unlock;
ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
if (ret)
goto out_unlock;
}
/* don't make the dst file partly checksummed */
if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
(BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
ret = -EINVAL;
goto out_unlock;
}
ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, &cmp);
if (ret)
goto out_unlock;
if (same_inode)
lock_extent_range(src, same_lock_start, same_lock_len);
else
btrfs_double_extent_lock(src, loff, dst, dst_loff, len);
/* pass original length for comparison so we stay within i_size */
ret = btrfs_cmp_data(src, loff, dst, dst_loff, olen, &cmp);
if (ret == 0)
ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1);
if (same_inode)
unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start,
same_lock_start + same_lock_len - 1);
else
btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
btrfs_cmp_data_free(&cmp);
out_unlock:
if (same_inode)
mutex_unlock(&src->i_mutex);
else
btrfs_double_inode_unlock(src, dst);
return ret;
}
#define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024)
static long btrfs_ioctl_file_extent_same(struct file *file,
struct btrfs_ioctl_same_args __user *argp)
{
struct btrfs_ioctl_same_args *same = NULL;
struct btrfs_ioctl_same_extent_info *info;
struct inode *src = file_inode(file);
u64 off;
u64 len;
int i;
int ret;
unsigned long size;
u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
bool is_admin = capable(CAP_SYS_ADMIN);
u16 count;
if (!(file->f_mode & FMODE_READ))
return -EINVAL;
ret = mnt_want_write_file(file);
if (ret)
return ret;
if (get_user(count, &argp->dest_count)) {
ret = -EFAULT;
goto out;
}
size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
same = memdup_user(argp, size);
if (IS_ERR(same)) {
ret = PTR_ERR(same);
same = NULL;
goto out;
}
off = same->logical_offset;
len = same->length;
/*
* Limit the total length we will dedupe for each operation.
* This is intended to bound the total time spent in this
* ioctl to something sane.
*/
if (len > BTRFS_MAX_DEDUPE_LEN)
len = BTRFS_MAX_DEDUPE_LEN;
if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
/*
* Btrfs does not support blocksize < page_size. As a
* result, btrfs_cmp_data() won't correctly handle
* this situation without an update.
*/
ret = -EINVAL;
goto out;
}
ret = -EISDIR;
if (S_ISDIR(src->i_mode))
goto out;
ret = -EACCES;
if (!S_ISREG(src->i_mode))
goto out;
/* pre-format output fields to sane values */
for (i = 0; i < count; i++) {
same->info[i].bytes_deduped = 0ULL;
same->info[i].status = 0;
}
for (i = 0, info = same->info; i < count; i++, info++) {
struct inode *dst;
struct fd dst_file = fdget(info->fd);
if (!dst_file.file) {
info->status = -EBADF;
continue;
}
dst = file_inode(dst_file.file);
if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
info->status = -EINVAL;
} else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
info->status = -EXDEV;
} else if (S_ISDIR(dst->i_mode)) {
info->status = -EISDIR;
} else if (!S_ISREG(dst->i_mode)) {
info->status = -EACCES;
} else {
info->status = btrfs_extent_same(src, off, len, dst,
info->logical_offset);
if (info->status == 0)
info->bytes_deduped += len;
}
fdput(dst_file);
}
ret = copy_to_user(argp, same, size);
if (ret)
ret = -EFAULT;
out:
mnt_drop_write_file(file);
kfree(same);
return ret;
}
static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
struct inode *inode,
u64 endoff,
const u64 destoff,
const u64 olen,
int no_time_update)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
int ret;
inode_inc_iversion(inode);
if (!no_time_update)
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.
*/
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);
out:
return ret;
}
static void clone_update_extent_map(struct inode *inode,
const struct btrfs_trans_handle *trans,
const struct btrfs_path *path,
const u64 hole_offset,
const u64 hole_len)
{
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
struct extent_map *em;
int ret;
em = alloc_extent_map();
if (!em) {
set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
&BTRFS_I(inode)->runtime_flags);
return;
}
if (path) {
struct btrfs_file_extent_item *fi;
fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_file_extent_item);
btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
em->generation = -1;
if (btrfs_file_extent_type(path->nodes[0], fi) ==
BTRFS_FILE_EXTENT_INLINE)
set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
&BTRFS_I(inode)->runtime_flags);
} else {
em->start = hole_offset;
em->len = hole_len;
em->ram_bytes = em->len;
em->orig_start = hole_offset;
em->block_start = EXTENT_MAP_HOLE;
em->block_len = 0;
em->orig_block_len = 0;
em->compress_type = BTRFS_COMPRESS_NONE;
em->generation = trans->transid;
}
while (1) {
write_lock(&em_tree->lock);
ret = add_extent_mapping(em_tree, em, 1);
write_unlock(&em_tree->lock);
if (ret != -EEXIST) {
free_extent_map(em);
break;
}
btrfs_drop_extent_cache(inode, em->start,
em->start + em->len - 1, 0);
}
if (ret)
set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
&BTRFS_I(inode)->runtime_flags);
}
/*
* Make sure we do not end up inserting an inline extent into a file that has
* already other (non-inline) extents. If a file has an inline extent it can
* not have any other extents and the (single) inline extent must start at the
* file offset 0. Failing to respect these rules will lead to file corruption,
* resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc
*
* We can have extents that have been already written to disk or we can have
* dirty ranges still in delalloc, in which case the extent maps and items are
* created only when we run delalloc, and the delalloc ranges might fall outside
* the range we are currently locking in the inode's io tree. So we check the
* inode's i_size because of that (i_size updates are done while holding the
* i_mutex, which we are holding here).
* We also check to see if the inode has a size not greater than "datal" but has
* extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are
* protected against such concurrent fallocate calls by the i_mutex).
*
* If the file has no extents but a size greater than datal, do not allow the
* copy because we would need turn the inline extent into a non-inline one (even
* with NO_HOLES enabled). If we find our destination inode only has one inline
* extent, just overwrite it with the source inline extent if its size is less
* than the source extent's size, or we could copy the source inline extent's
* data into the destination inode's inline extent if the later is greater then
* the former.
*/
static int clone_copy_inline_extent(struct inode *src,
struct inode *dst,
struct btrfs_trans_handle *trans,
struct btrfs_path *path,
struct btrfs_key *new_key,
const u64 drop_start,
const u64 datal,
const u64 skip,
const u64 size,
char *inline_data)
{
struct btrfs_root *root = BTRFS_I(dst)->root;
const u64 aligned_end = ALIGN(new_key->offset + datal,
root->sectorsize);
int ret;
struct btrfs_key key;
if (new_key->offset > 0)
return -EOPNOTSUPP;
key.objectid = btrfs_ino(dst);
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = 0;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0) {
return ret;
} else if (ret > 0) {
if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
ret = btrfs_next_leaf(root, path);
if (ret < 0)
return ret;
else if (ret > 0)
goto copy_inline_extent;
}
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
if (key.objectid == btrfs_ino(dst) &&
key.type == BTRFS_EXTENT_DATA_KEY) {
ASSERT(key.offset > 0);
return -EOPNOTSUPP;
}
} else if (i_size_read(dst) <= datal) {
struct btrfs_file_extent_item *ei;
u64 ext_len;
/*
* If the file size is <= datal, make sure there are no other
* extents following (can happen do to an fallocate call with
* the flag FALLOC_FL_KEEP_SIZE).
*/
ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_file_extent_item);
/*
* If it's an inline extent, it can not have other extents
* following it.
*/
if (btrfs_file_extent_type(path->nodes[0], ei) ==
BTRFS_FILE_EXTENT_INLINE)
goto copy_inline_extent;
ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
if (ext_len > aligned_end)
return -EOPNOTSUPP;
ret = btrfs_next_item(root, path);
if (ret < 0) {
return ret;
} else if (ret == 0) {
btrfs_item_key_to_cpu(path->nodes[0], &key,
path->slots[0]);
if (key.objectid == btrfs_ino(dst) &&
key.type == BTRFS_EXTENT_DATA_KEY)
return -EOPNOTSUPP;
}
}
copy_inline_extent:
/*
* We have no extent items, or we have an extent at offset 0 which may
* or may not be inlined. All these cases are dealt the same way.
*/
if (i_size_read(dst) > datal) {
/*
* If the destination inode has an inline extent...
* This would require copying the data from the source inline
* extent into the beginning of the destination's inline extent.
* But this is really complex, both extents can be compressed
* or just one of them, which would require decompressing and
* re-compressing data (which could increase the new compressed
* size, not allowing the compressed data to fit anymore in an
* inline extent).
* So just don't support this case for now (it should be rare,
* we are not really saving space when cloning inline extents).
*/
return -EOPNOTSUPP;
}
btrfs_release_path(path);
ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1);
if (ret)
return ret;
ret = btrfs_insert_empty_item(trans, root, path, new_key, size);
if (ret)
return ret;
if (skip) {
const u32 start = btrfs_file_extent_calc_inline_size(0);
memmove(inline_data + start, inline_data + start + skip, datal);
}
write_extent_buffer(path->nodes[0], inline_data,
btrfs_item_ptr_offset(path->nodes[0],
path->slots[0]),
size);
inode_add_bytes(dst, datal);
return 0;
}
/**
* btrfs_clone() - clone a range from inode file to another
*
* @src: Inode to clone from
* @inode: Inode to clone to
* @off: Offset within source to start clone from
* @olen: Original length, passed by user, of range to clone
* @olen_aligned: Block-aligned value of olen
* @destoff: Offset within @inode to start clone
* @no_time_update: Whether to update mtime/ctime on the target inode
*/
static int btrfs_clone(struct inode *src, struct inode *inode,
const u64 off, const u64 olen, const u64 olen_aligned,
const u64 destoff, int no_time_update)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_path *path = NULL;
struct extent_buffer *leaf;
struct btrfs_trans_handle *trans;
char *buf = NULL;
struct btrfs_key key;
u32 nritems;
int slot;
int ret;
const u64 len = olen_aligned;
u64 last_dest_end = destoff;
ret = -ENOMEM;
buf = vmalloc(root->nodesize);
if (!buf)
return ret;
path = btrfs_alloc_path();
if (!path) {
vfree(buf);
return ret;
}
path->reada = 2;
/* clone data */
key.objectid = btrfs_ino(src);
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = off;
while (1) {
u64 next_key_min_offset = key.offset + 1;
/*
* note the key will change type as we walk through the
* tree.
*/
path->leave_spinning = 1;
ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
0, 0);
if (ret < 0)
goto out;
/*
* First search, if no extent item that starts at offset off was
* found but the previous item is an extent item, it's possible
* it might overlap our target range, therefore process it.
*/
if (key.offset == off && ret > 0 && path->slots[0] > 0) {
btrfs_item_key_to_cpu(path->nodes[0], &key,
path->slots[0] - 1);
if (key.type == BTRFS_EXTENT_DATA_KEY)
path->slots[0]--;
}
nritems = btrfs_header_nritems(path->nodes[0]);
process_slot:
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 (key.type > BTRFS_EXTENT_DATA_KEY ||
key.objectid != btrfs_ino(src))
break;
if (key.type == 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 drop_start;
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);
}
/*
* The first search might have left us at an extent
* item that ends before our target range's start, can
* happen if we have holes and NO_HOLES feature enabled.
*/
if (key.offset + datal <= off) {
path->slots[0]++;
goto process_slot;
} else if (key.offset >= off + len) {
break;
}
next_key_min_offset = key.offset + datal;
size = btrfs_item_size_nr(leaf, slot);
read_extent_buffer(leaf, buf,
btrfs_item_ptr_offset(leaf, slot),
size);
btrfs_release_path(path);
path->leave_spinning = 0;
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;
/*
* Deal with a hole that doesn't have an extent item
* that represents it (NO_HOLES feature enabled).
* This hole is either in the middle of the cloning
* range or at the beginning (fully overlaps it or
* partially overlaps it).
*/
if (new_key.offset != last_dest_end)
drop_start = last_dest_end;
else
drop_start = new_key.offset;
/*
* 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 ------------- |
*/
/* subtract range b */
if (key.offset + datal > off + len)
datal = off + len - key.offset;
/* subtract range a */
if (off > key.offset) {
datao += off - key.offset;
datal -= off - key.offset;
}
ret = btrfs_drop_extents(trans, root, inode,
drop_start,
new_key.offset + datal,
1);
if (ret) {
if (ret != -EOPNOTSUPP)
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);
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 = clone_copy_inline_extent(src, inode,
trans, path,
&new_key,
drop_start,
datal,
skip, size, buf);
if (ret) {
if (ret != -EOPNOTSUPP)
btrfs_abort_transaction(trans,
root,
ret);
btrfs_end_transaction(trans, root);
goto out;
}
leaf = path->nodes[0];
slot = path->slots[0];
}
/* If we have an implicit hole (NO_HOLES feature). */
if (drop_start < new_key.offset)
clone_update_extent_map(inode, trans,
NULL, drop_start,
new_key.offset - drop_start);
clone_update_extent_map(inode, trans, path, 0, 0);
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(path);
last_dest_end = ALIGN(new_key.offset + datal,
root->sectorsize);
ret = clone_finish_inode_update(trans, inode,
last_dest_end,
destoff, olen,
no_time_update);
if (ret)
goto out;
if (new_key.offset + datal >= destoff + len)
break;
}
btrfs_release_path(path);
key.offset = next_key_min_offset;
}
ret = 0;
if (last_dest_end < destoff + len) {
/*
* We have an implicit hole (NO_HOLES feature is enabled) that
* fully or partially overlaps our cloning range at its end.
*/
btrfs_release_path(path);
/*
* 1 - remove extent(s)
* 1 - inode update
*/
trans = btrfs_start_transaction(root, 2);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out;
}
ret = btrfs_drop_extents(trans, root, inode,
last_dest_end, destoff + len, 1);
if (ret) {
if (ret != -EOPNOTSUPP)
btrfs_abort_transaction(trans, root, ret);
btrfs_end_transaction(trans, root);
goto out;
}
clone_update_extent_map(inode, trans, NULL, last_dest_end,
destoff + len - last_dest_end);
ret = clone_finish_inode_update(trans, inode, destoff + len,
destoff, olen, no_time_update);
}
out:
btrfs_free_path(path);
vfree(buf);
return ret;
}
static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
u64 off, u64 olen, u64 destoff)
{
struct inode *inode = file_inode(file);
struct inode *src = file_inode(file_src);
struct btrfs_root *root = BTRFS_I(inode)->root;
int ret;
u64 len = olen;
u64 bs = root->fs_info->sb->s_blocksize;
int same_inode = src == inode;
/*
* 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.
*
* - split destination inode's inline extents. The inline extents can
* be either compressed or non-compressed.
*/
if (btrfs_root_readonly(root))
return -EROFS;
if (file_src->f_path.mnt != file->f_path.mnt ||
src->i_sb != inode->i_sb)
return -EXDEV;
/* don't make the dst file partly checksummed */
if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
return -EINVAL;
if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
return -EISDIR;
if (!same_inode) {
btrfs_double_inode_lock(src, inode);
} else {
mutex_lock(&src->i_mutex);
}
/* 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;
/* verify if ranges are overlapped within the same file */
if (same_inode) {
if (destoff + len > off && destoff < off + len)
goto out_unlock;
}
if (destoff > inode->i_size) {
ret = btrfs_cont_expand(inode, inode->i_size, destoff);
if (ret)
goto out_unlock;
}
/*
* Lock the target range too. Right after we replace the file extent
* items in the fs tree (which now point to the cloned data), we might
* have a worker replace them with extent items relative to a write
* operation that was issued before this clone operation (i.e. confront
* with inode.c:btrfs_finish_ordered_io).
*/
if (same_inode) {
u64 lock_start = min_t(u64, off, destoff);
u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
lock_extent_range(src, lock_start, lock_len);
} else {
btrfs_double_extent_lock(src, off, inode, destoff, len);
}
ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
if (same_inode) {
u64 lock_start = min_t(u64, off, destoff);
u64 lock_end = max_t(u64, off, destoff) + len - 1;
unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
} else {
btrfs_double_extent_unlock(src, off, inode, destoff, len);
}
/*
* Truncate page cache pages so that future reads will see the cloned
* data immediately and not the previous data.
*/
truncate_inode_pages_range(&inode->i_data, destoff,
PAGE_CACHE_ALIGN(destoff + len) - 1);
out_unlock:
if (!same_inode)
btrfs_double_inode_unlock(src, inode);
else
mutex_unlock(&src->i_mutex);
return ret;
}
ssize_t btrfs_copy_file_range(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
size_t len, unsigned int flags)
{
ssize_t ret;
ret = btrfs_clone_files(file_out, file_in, pos_in, len, pos_out);
if (ret == 0)
ret = len;
return ret;
}
int btrfs_clone_file_range(struct file *src_file, loff_t off,
struct file *dst_file, loff_t destoff, u64 len)
{
return btrfs_clone_files(dst_file, src_file, off, len, destoff);
}
/*
* 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 = file_inode(file);
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 = file_inode(file);
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;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
if (copy_from_user(&objectid, argp, sizeof(objectid))) {
ret = -EFAULT;
goto out;
}
if (!objectid)
objectid = BTRFS_FS_TREE_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)) {
ret = PTR_ERR(new_root);
goto out;
}
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto out;
}
path->leave_spinning = 1;
trans = btrfs_start_transaction(root, 1);
if (IS_ERR(trans)) {
btrfs_free_path(path);
ret = PTR_ERR(trans);
goto out;
}
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);
btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
"item, this isn't going to work");
ret = -ENOENT;
goto out;
}
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);
out:
mnt_drop_write_file(file);
return ret;
}
void btrfs_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);
}
}
static 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);
}
/*
* Global block reserve, exported as a space_info
*/
slot_count++;
/* 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])) {
btrfs_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);
}
/*
* Add global block reserve
*/
if (slot_count) {
struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
spin_lock(&block_rsv->lock);
space.total_bytes = block_rsv->size;
space.used_bytes = block_rsv->size - block_rsv->reserved;
spin_unlock(&block_rsv->lock);
space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
memcpy(dest, &space, sizeof(space));
space_args.total_spaces++;
}
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 = file_inode(file);
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 btrfs_root *root,
void __user *argp)
{
struct btrfs_trans_handle *trans;
u64 transid;
int ret;
trans = btrfs_attach_transaction_barrier(root);
if (IS_ERR(trans)) {
if (PTR_ERR(trans) != -ENOENT)
return PTR_ERR(trans);
/* No running transaction, don't bother */
transid = root->fs_info->last_trans_committed;
goto out;
}
transid = trans->transid;
ret = btrfs_commit_transaction_async(trans, root, 0);
if (ret) {
btrfs_end_transaction(trans, root);
return ret;
}
out:
if (argp)
if (copy_to_user(argp, &transid, sizeof(transid)))
return -EFAULT;
return 0;
}
static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
void __user *argp)
{
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 file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
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);
if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
ret = mnt_want_write_file(file);
if (ret)
goto out;
}
ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
&sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
0);
if (copy_to_user(arg, sa, sizeof(*sa)))
ret = -EFAULT;
if (!(sa->flags & BTRFS_SCRUB_READONLY))
mnt_drop_write_file(file);
out:
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->fs_info);
}
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_get_dev_stats(struct btrfs_root *root,
void __user *arg)
{
struct btrfs_ioctl_get_dev_stats *sa;
int ret;
sa = memdup_user(arg, sizeof(*sa));
if (IS_ERR(sa))
return PTR_ERR(sa);
if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
kfree(sa);
return -EPERM;
}
ret = btrfs_get_dev_stats(root, sa);
if (copy_to_user(arg, sa, sizeof(*sa)))
ret = -EFAULT;
kfree(sa);
return ret;
}
static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
{
struct btrfs_ioctl_dev_replace_args *p;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
p = memdup_user(arg, sizeof(*p));
if (IS_ERR(p))
return PTR_ERR(p);
switch (p->cmd) {
case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
if (root->fs_info->sb->s_flags & MS_RDONLY) {
ret = -EROFS;
goto out;
}
if (atomic_xchg(
&root->fs_info->mutually_exclusive_operation_running,
1)) {
ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
} else {
ret = btrfs_dev_replace_start(root, p);
atomic_set(
&root->fs_info->mutually_exclusive_operation_running,
0);
}
break;
case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
btrfs_dev_replace_status(root->fs_info, p);
ret = 0;
break;
case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
ret = btrfs_dev_replace_cancel(root->fs_info, p);
break;
default:
ret = -EINVAL;
break;
}
if (copy_to_user(arg, p, sizeof(*p)))
ret = -EFAULT;
out:
kfree(p);
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_DAC_READ_SEARCH))
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;
struct btrfs_ioctl_logical_ino_args *loi;
struct btrfs_data_container *inodes = NULL;
struct btrfs_path *path = NULL;
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, 64 * 1024);
inodes = init_data_container(size);
if (IS_ERR(inodes)) {
ret = PTR_ERR(inodes);
inodes = NULL;
goto out;
}
ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
build_ino_list, inodes);
if (ret == -EINVAL)
ret = -ENOENT;
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);
vfree(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 file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_ioctl_balance_args *bargs;
struct btrfs_balance_control *bctl;
bool need_unlock; /* for mut. excl. ops lock */
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
again:
if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
mutex_lock(&fs_info->volume_mutex);
mutex_lock(&fs_info->balance_mutex);
need_unlock = true;
goto locked;
}
/*
* mut. excl. ops lock is locked. Three possibilites:
* (1) some other op is running
* (2) balance is running
* (3) balance is paused -- special case (think resume)
*/
mutex_lock(&fs_info->balance_mutex);
if (fs_info->balance_ctl) {
/* this is either (2) or (3) */
if (!atomic_read(&fs_info->balance_running)) {
mutex_unlock(&fs_info->balance_mutex);
if (!mutex_trylock(&fs_info->volume_mutex))
goto again;
mutex_lock(&fs_info->balance_mutex);
if (fs_info->balance_ctl &&
!atomic_read(&fs_info->balance_running)) {
/* this is (3) */
need_unlock = false;
goto locked;
}
mutex_unlock(&fs_info->balance_mutex);
mutex_unlock(&fs_info->volume_mutex);
goto again;
} else {
/* this is (2) */
mutex_unlock(&fs_info->balance_mutex);
ret = -EINPROGRESS;
goto out;
}
} else {
/* this is (1) */
mutex_unlock(&fs_info->balance_mutex);
ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
goto out;
}
locked:
BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
if (arg) {
bargs = memdup_user(arg, sizeof(*bargs));
if (IS_ERR(bargs)) {
ret = PTR_ERR(bargs);
goto out_unlock;
}
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;
}
if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
ret = -EINVAL;
goto out_bctl;
}
do_balance:
/*
* Ownership of bctl and mutually_exclusive_operation_running
* goes to to btrfs_balance. bctl is freed in __cancel_balance,
* or, if restriper was paused all the way until unmount, in
* free_fs_info. mutually_exclusive_operation_running is
* cleared in __cancel_balance.
*/
need_unlock = false;
ret = btrfs_balance(bctl, bargs);
bctl = NULL;
if (arg) {
if (copy_to_user(arg, bargs, sizeof(*bargs)))
ret = -EFAULT;
}
out_bctl:
kfree(bctl);
out_bargs:
kfree(bargs);
out_unlock:
mutex_unlock(&fs_info->balance_mutex);
mutex_unlock(&fs_info->volume_mutex);
if (need_unlock)
atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
out:
mnt_drop_write_file(file);
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;
}
static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_ioctl_quota_ctl_args *sa;
struct btrfs_trans_handle *trans = NULL;
int ret;
int err;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
sa = memdup_user(arg, sizeof(*sa));
if (IS_ERR(sa)) {
ret = PTR_ERR(sa);
goto drop_write;
}
down_write(&root->fs_info->subvol_sem);
trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out;
}
switch (sa->cmd) {
case BTRFS_QUOTA_CTL_ENABLE:
ret = btrfs_quota_enable(trans, root->fs_info);
break;
case BTRFS_QUOTA_CTL_DISABLE:
ret = btrfs_quota_disable(trans, root->fs_info);
break;
default:
ret = -EINVAL;
break;
}
err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
if (err && !ret)
ret = err;
out:
kfree(sa);
up_write(&root->fs_info->subvol_sem);
drop_write:
mnt_drop_write_file(file);
return ret;
}
static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_ioctl_qgroup_assign_args *sa;
struct btrfs_trans_handle *trans;
int ret;
int err;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
sa = memdup_user(arg, sizeof(*sa));
if (IS_ERR(sa)) {
ret = PTR_ERR(sa);
goto drop_write;
}
trans = btrfs_join_transaction(root);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out;
}
/* FIXME: check if the IDs really exist */
if (sa->assign) {
ret = btrfs_add_qgroup_relation(trans, root->fs_info,
sa->src, sa->dst);
} else {
ret = btrfs_del_qgroup_relation(trans, root->fs_info,
sa->src, sa->dst);
}
/* update qgroup status and info */
err = btrfs_run_qgroups(trans, root->fs_info);
if (err < 0)
btrfs_std_error(root->fs_info, ret,
"failed to update qgroup status and info\n");
err = btrfs_end_transaction(trans, root);
if (err && !ret)
ret = err;
out:
kfree(sa);
drop_write:
mnt_drop_write_file(file);
return ret;
}
static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_ioctl_qgroup_create_args *sa;
struct btrfs_trans_handle *trans;
int ret;
int err;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
sa = memdup_user(arg, sizeof(*sa));
if (IS_ERR(sa)) {
ret = PTR_ERR(sa);
goto drop_write;
}
if (!sa->qgroupid) {
ret = -EINVAL;
goto out;
}
trans = btrfs_join_transaction(root);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out;
}
/* FIXME: check if the IDs really exist */
if (sa->create) {
ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid);
} else {
ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
}
err = btrfs_end_transaction(trans, root);
if (err && !ret)
ret = err;
out:
kfree(sa);
drop_write:
mnt_drop_write_file(file);
return ret;
}
static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_ioctl_qgroup_limit_args *sa;
struct btrfs_trans_handle *trans;
int ret;
int err;
u64 qgroupid;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
sa = memdup_user(arg, sizeof(*sa));
if (IS_ERR(sa)) {
ret = PTR_ERR(sa);
goto drop_write;
}
trans = btrfs_join_transaction(root);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out;
}
qgroupid = sa->qgroupid;
if (!qgroupid) {
/* take the current subvol as qgroup */
qgroupid = root->root_key.objectid;
}
/* FIXME: check if the IDs really exist */
ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
err = btrfs_end_transaction(trans, root);
if (err && !ret)
ret = err;
out:
kfree(sa);
drop_write:
mnt_drop_write_file(file);
return ret;
}
static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_ioctl_quota_rescan_args *qsa;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
qsa = memdup_user(arg, sizeof(*qsa));
if (IS_ERR(qsa)) {
ret = PTR_ERR(qsa);
goto drop_write;
}
if (qsa->flags) {
ret = -EINVAL;
goto out;
}
ret = btrfs_qgroup_rescan(root->fs_info);
out:
kfree(qsa);
drop_write:
mnt_drop_write_file(file);
return ret;
}
static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_ioctl_quota_rescan_args *qsa;
int ret = 0;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
if (!qsa)
return -ENOMEM;
if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
qsa->flags = 1;
qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
}
if (copy_to_user(arg, qsa, sizeof(*qsa)))
ret = -EFAULT;
kfree(qsa);
return ret;
}
static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
return btrfs_qgroup_wait_for_completion(root->fs_info);
}
static long _btrfs_ioctl_set_received_subvol(struct file *file,
struct btrfs_ioctl_received_subvol_args *sa)
{
struct inode *inode = file_inode(file);
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_root_item *root_item = &root->root_item;
struct btrfs_trans_handle *trans;
struct timespec ct = CURRENT_TIME;
int ret = 0;
int received_uuid_changed;
if (!inode_owner_or_capable(inode))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret < 0)
return ret;
down_write(&root->fs_info->subvol_sem);
if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
ret = -EINVAL;
goto out;
}
if (btrfs_root_readonly(root)) {
ret = -EROFS;
goto out;
}
/*
* 1 - root item
* 2 - uuid items (received uuid + subvol uuid)
*/
trans = btrfs_start_transaction(root, 3);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
trans = NULL;
goto out;
}
sa->rtransid = trans->transid;
sa->rtime.sec = ct.tv_sec;
sa->rtime.nsec = ct.tv_nsec;
received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
BTRFS_UUID_SIZE);
if (received_uuid_changed &&
!btrfs_is_empty_uuid(root_item->received_uuid))
btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
root_item->received_uuid,
BTRFS_UUID_KEY_RECEIVED_SUBVOL,
root->root_key.objectid);
memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
btrfs_set_root_stransid(root_item, sa->stransid);
btrfs_set_root_rtransid(root_item, sa->rtransid);
btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
ret = btrfs_update_root(trans, root->fs_info->tree_root,
&root->root_key, &root->root_item);
if (ret < 0) {
btrfs_end_transaction(trans, root);
goto out;
}
if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
sa->uuid,
BTRFS_UUID_KEY_RECEIVED_SUBVOL,
root->root_key.objectid);
if (ret < 0 && ret != -EEXIST) {
btrfs_abort_transaction(trans, root, ret);
goto out;
}
}
ret = btrfs_commit_transaction(trans, root);
if (ret < 0) {
btrfs_abort_transaction(trans, root, ret);
goto out;
}
out:
up_write(&root->fs_info->subvol_sem);
mnt_drop_write_file(file);
return ret;
}
#ifdef CONFIG_64BIT
static long btrfs_ioctl_set_received_subvol_32(struct file *file,
void __user *arg)
{
struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
struct btrfs_ioctl_received_subvol_args *args64 = NULL;
int ret = 0;
args32 = memdup_user(arg, sizeof(*args32));
if (IS_ERR(args32)) {
ret = PTR_ERR(args32);
args32 = NULL;
goto out;
}
args64 = kmalloc(sizeof(*args64), GFP_NOFS);
if (!args64) {
ret = -ENOMEM;
goto out;
}
memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
args64->stransid = args32->stransid;
args64->rtransid = args32->rtransid;
args64->stime.sec = args32->stime.sec;
args64->stime.nsec = args32->stime.nsec;
args64->rtime.sec = args32->rtime.sec;
args64->rtime.nsec = args32->rtime.nsec;
args64->flags = args32->flags;
ret = _btrfs_ioctl_set_received_subvol(file, args64);
if (ret)
goto out;
memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
args32->stransid = args64->stransid;
args32->rtransid = args64->rtransid;
args32->stime.sec = args64->stime.sec;
args32->stime.nsec = args64->stime.nsec;
args32->rtime.sec = args64->rtime.sec;
args32->rtime.nsec = args64->rtime.nsec;
args32->flags = args64->flags;
ret = copy_to_user(arg, args32, sizeof(*args32));
if (ret)
ret = -EFAULT;
out:
kfree(args32);
kfree(args64);
return ret;
}
#endif
static long btrfs_ioctl_set_received_subvol(struct file *file,
void __user *arg)
{
struct btrfs_ioctl_received_subvol_args *sa = NULL;
int ret = 0;
sa = memdup_user(arg, sizeof(*sa));
if (IS_ERR(sa)) {
ret = PTR_ERR(sa);
sa = NULL;
goto out;
}
ret = _btrfs_ioctl_set_received_subvol(file, sa);
if (ret)
goto out;
ret = copy_to_user(arg, sa, sizeof(*sa));
if (ret)
ret = -EFAULT;
out:
kfree(sa);
return ret;
}
static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
size_t len;
int ret;
char label[BTRFS_LABEL_SIZE];
spin_lock(&root->fs_info->super_lock);
memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
spin_unlock(&root->fs_info->super_lock);
len = strnlen(label, BTRFS_LABEL_SIZE);
if (len == BTRFS_LABEL_SIZE) {
btrfs_warn(root->fs_info,
"label is too long, return the first %zu bytes", --len);
}
ret = copy_to_user(arg, label, len);
return ret ? -EFAULT : 0;
}
static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_super_block *super_block = root->fs_info->super_copy;
struct btrfs_trans_handle *trans;
char label[BTRFS_LABEL_SIZE];
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (copy_from_user(label, arg, sizeof(label)))
return -EFAULT;
if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
BTRFS_LABEL_SIZE - 1);
return -EINVAL;
}
ret = mnt_want_write_file(file);
if (ret)
return ret;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out_unlock;
}
spin_lock(&root->fs_info->super_lock);
strcpy(super_block->label, label);
spin_unlock(&root->fs_info->super_lock);
ret = btrfs_commit_transaction(trans, root);
out_unlock:
mnt_drop_write_file(file);
return ret;
}
#define INIT_FEATURE_FLAGS(suffix) \
{ .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
.compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
.incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
static int btrfs_ioctl_get_supported_features(struct file *file,
void __user *arg)
{
static struct btrfs_ioctl_feature_flags features[3] = {
INIT_FEATURE_FLAGS(SUPP),
INIT_FEATURE_FLAGS(SAFE_SET),
INIT_FEATURE_FLAGS(SAFE_CLEAR)
};
if (copy_to_user(arg, &features, sizeof(features)))
return -EFAULT;
return 0;
}
static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_super_block *super_block = root->fs_info->super_copy;
struct btrfs_ioctl_feature_flags features;
features.compat_flags = btrfs_super_compat_flags(super_block);
features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
features.incompat_flags = btrfs_super_incompat_flags(super_block);
if (copy_to_user(arg, &features, sizeof(features)))
return -EFAULT;
return 0;
}
static int check_feature_bits(struct btrfs_root *root,
enum btrfs_feature_set set,
u64 change_mask, u64 flags, u64 supported_flags,
u64 safe_set, u64 safe_clear)
{
const char *type = btrfs_feature_set_names[set];
char *names;
u64 disallowed, unsupported;
u64 set_mask = flags & change_mask;
u64 clear_mask = ~flags & change_mask;
unsupported = set_mask & ~supported_flags;
if (unsupported) {
names = btrfs_printable_features(set, unsupported);
if (names) {
btrfs_warn(root->fs_info,
"this kernel does not support the %s feature bit%s",
names, strchr(names, ',') ? "s" : "");
kfree(names);
} else
btrfs_warn(root->fs_info,
"this kernel does not support %s bits 0x%llx",
type, unsupported);
return -EOPNOTSUPP;
}
disallowed = set_mask & ~safe_set;
if (disallowed) {
names = btrfs_printable_features(set, disallowed);
if (names) {
btrfs_warn(root->fs_info,
"can't set the %s feature bit%s while mounted",
names, strchr(names, ',') ? "s" : "");
kfree(names);
} else
btrfs_warn(root->fs_info,
"can't set %s bits 0x%llx while mounted",
type, disallowed);
return -EPERM;
}
disallowed = clear_mask & ~safe_clear;
if (disallowed) {
names = btrfs_printable_features(set, disallowed);
if (names) {
btrfs_warn(root->fs_info,
"can't clear the %s feature bit%s while mounted",
names, strchr(names, ',') ? "s" : "");
kfree(names);
} else
btrfs_warn(root->fs_info,
"can't clear %s bits 0x%llx while mounted",
type, disallowed);
return -EPERM;
}
return 0;
}
#define check_feature(root, change_mask, flags, mask_base) \
check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \
BTRFS_FEATURE_ ## mask_base ## _SUPP, \
BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
struct btrfs_super_block *super_block = root->fs_info->super_copy;
struct btrfs_ioctl_feature_flags flags[2];
struct btrfs_trans_handle *trans;
u64 newflags;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (copy_from_user(flags, arg, sizeof(flags)))
return -EFAULT;
/* Nothing to do */
if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
!flags[0].incompat_flags)
return 0;
ret = check_feature(root, flags[0].compat_flags,
flags[1].compat_flags, COMPAT);
if (ret)
return ret;
ret = check_feature(root, flags[0].compat_ro_flags,
flags[1].compat_ro_flags, COMPAT_RO);
if (ret)
return ret;
ret = check_feature(root, flags[0].incompat_flags,
flags[1].incompat_flags, INCOMPAT);
if (ret)
return ret;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans))
return PTR_ERR(trans);
spin_lock(&root->fs_info->super_lock);
newflags = btrfs_super_compat_flags(super_block);
newflags |= flags[0].compat_flags & flags[1].compat_flags;
newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
btrfs_set_super_compat_flags(super_block, newflags);
newflags = btrfs_super_compat_ro_flags(super_block);
newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
btrfs_set_super_compat_ro_flags(super_block, newflags);
newflags = btrfs_super_incompat_flags(super_block);
newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
btrfs_set_super_incompat_flags(super_block, newflags);
spin_unlock(&root->fs_info->super_lock);
return btrfs_commit_transaction(trans, root);
}
long btrfs_ioctl(struct file *file, unsigned int
cmd, unsigned long arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->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_SUBVOL_CREATE_V2:
return btrfs_ioctl_snap_create_v2(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(file, argp);
case BTRFS_IOC_ADD_DEV:
return btrfs_ioctl_add_dev(root, argp);
case BTRFS_IOC_RM_DEV:
return btrfs_ioctl_rm_dev(file, 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(file, NULL);
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_TREE_SEARCH_V2:
return btrfs_ioctl_tree_search_v2(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: {
int ret;
ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
if (ret)
return ret;
ret = btrfs_sync_fs(file_inode(file)->i_sb, 1);
/*
* The transaction thread may want to do more work,
* namely it pokes the cleaner ktread that will start
* processing uncleaned subvols.
*/
wake_up_process(root->fs_info->transaction_kthread);
return ret;
}
case BTRFS_IOC_START_SYNC:
return btrfs_ioctl_start_sync(root, argp);
case BTRFS_IOC_WAIT_SYNC:
return btrfs_ioctl_wait_sync(root, argp);
case BTRFS_IOC_SCRUB:
return btrfs_ioctl_scrub(file, 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(file, 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);
case BTRFS_IOC_SET_RECEIVED_SUBVOL:
return btrfs_ioctl_set_received_subvol(file, argp);
#ifdef CONFIG_64BIT
case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
return btrfs_ioctl_set_received_subvol_32(file, argp);
#endif
case BTRFS_IOC_SEND:
return btrfs_ioctl_send(file, argp);
case BTRFS_IOC_GET_DEV_STATS:
return btrfs_ioctl_get_dev_stats(root, argp);
case BTRFS_IOC_QUOTA_CTL:
return btrfs_ioctl_quota_ctl(file, argp);
case BTRFS_IOC_QGROUP_ASSIGN:
return btrfs_ioctl_qgroup_assign(file, argp);
case BTRFS_IOC_QGROUP_CREATE:
return btrfs_ioctl_qgroup_create(file, argp);
case BTRFS_IOC_QGROUP_LIMIT:
return btrfs_ioctl_qgroup_limit(file, argp);
case BTRFS_IOC_QUOTA_RESCAN:
return btrfs_ioctl_quota_rescan(file, argp);
case BTRFS_IOC_QUOTA_RESCAN_STATUS:
return btrfs_ioctl_quota_rescan_status(file, argp);
case BTRFS_IOC_QUOTA_RESCAN_WAIT:
return btrfs_ioctl_quota_rescan_wait(file, argp);
case BTRFS_IOC_DEV_REPLACE:
return btrfs_ioctl_dev_replace(root, argp);
case BTRFS_IOC_GET_FSLABEL:
return btrfs_ioctl_get_fslabel(file, argp);
case BTRFS_IOC_SET_FSLABEL:
return btrfs_ioctl_set_fslabel(file, argp);
case BTRFS_IOC_FILE_EXTENT_SAME:
return btrfs_ioctl_file_extent_same(file, argp);
case BTRFS_IOC_GET_SUPPORTED_FEATURES:
return btrfs_ioctl_get_supported_features(file, argp);
case BTRFS_IOC_GET_FEATURES:
return btrfs_ioctl_get_features(file, argp);
case BTRFS_IOC_SET_FEATURES:
return btrfs_ioctl_set_features(file, argp);
}
return -ENOTTY;
}
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