korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-14 15:54:15 +08:00
Code Issues Packages Projects Releases Wiki Activity
2d74fa3efc
linux/fs/btrfs/ioctl.c
Goldwyn Rodrigues 7984ae52bb btrfs: Perform locking/unlocking in btrfs_remap_file_range() 
Move code to make it more readable, so as locking and unlocking is
done in the same function. The generic checks that are now performed in
the locked section are unaffected.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-29 19:02:29 +02:00

5691 lines
139 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*/
#include <linux/kernel.h>
#include <linux/bio.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/string.h>
#include <linux/backing-dev.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/writeback.h>
#include <linux/compat.h>
#include <linux/security.h>
#include <linux/xattr.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/uuid.h>
#include <linux/btrfs.h>
#include <linux/uaccess.h>
#include <linux/iversion.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"
#include "tree-log.h"
#include "compression.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
#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
struct btrfs_ioctl_send_args_32 {
__s64 send_fd; /* in */
__u64 clone_sources_count; /* in */
compat_uptr_t clone_sources; /* in */
__u64 parent_root; /* in */
__u64 flags; /* in */
__u64 reserved[4]; /* in */
} __attribute__ ((__packed__));
#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
struct btrfs_ioctl_send_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 unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
unsigned int flags)
{
if (S_ISDIR(inode->i_mode))
return flags;
else if (S_ISREG(inode->i_mode))
return flags & ~FS_DIRSYNC_FL;
else
return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
}
/*
* Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
* ioctl.
*/
static unsigned int btrfs_inode_flags_to_fsflags(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_NOCOMPRESS)
iflags |= FS_NOCOMP_FL;
else if (flags & BTRFS_INODE_COMPRESS)
iflags |= FS_COMPR_FL;
return iflags;
}
/*
* Update inode->i_flags based on the btrfs internal flags.
*/
void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
{
struct btrfs_inode *binode = BTRFS_I(inode);
unsigned int new_fl = 0;
if (binode->flags & BTRFS_INODE_SYNC)
new_fl |= S_SYNC;
if (binode->flags & BTRFS_INODE_IMMUTABLE)
new_fl |= S_IMMUTABLE;
if (binode->flags & BTRFS_INODE_APPEND)
new_fl |= S_APPEND;
if (binode->flags & BTRFS_INODE_NOATIME)
new_fl |= S_NOATIME;
if (binode->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);
}
static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
{
struct btrfs_inode *binode = BTRFS_I(file_inode(file));
unsigned int flags = btrfs_inode_flags_to_fsflags(binode->flags);
if (copy_to_user(arg, &flags, sizeof(flags)))
return -EFAULT;
return 0;
}
/* Check if @flags are a supported and valid set of FS_*_FL flags */
static int check_fsflags(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_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_inode *binode = BTRFS_I(inode);
struct btrfs_root *root = binode->root;
struct btrfs_trans_handle *trans;
unsigned int fsflags, old_fsflags;
int ret;
u64 old_flags;
unsigned int old_i_flags;
umode_t mode;
if (!inode_owner_or_capable(inode))
return -EPERM;
if (btrfs_root_readonly(root))
return -EROFS;
if (copy_from_user(&fsflags, arg, sizeof(fsflags)))
return -EFAULT;
ret = check_fsflags(fsflags);
if (ret)
return ret;
ret = mnt_want_write_file(file);
if (ret)
return ret;
inode_lock(inode);
old_flags = binode->flags;
old_i_flags = inode->i_flags;
mode = inode->i_mode;
fsflags = btrfs_mask_fsflags_for_type(inode, fsflags);
old_fsflags = btrfs_inode_flags_to_fsflags(binode->flags);
if ((fsflags ^ old_fsflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
if (!capable(CAP_LINUX_IMMUTABLE)) {
ret = -EPERM;
goto out_unlock;
}
}
if (fsflags & FS_SYNC_FL)
binode->flags |= BTRFS_INODE_SYNC;
else
binode->flags &= ~BTRFS_INODE_SYNC;
if (fsflags & FS_IMMUTABLE_FL)
binode->flags |= BTRFS_INODE_IMMUTABLE;
else
binode->flags &= ~BTRFS_INODE_IMMUTABLE;
if (fsflags & FS_APPEND_FL)
binode->flags |= BTRFS_INODE_APPEND;
else
binode->flags &= ~BTRFS_INODE_APPEND;
if (fsflags & FS_NODUMP_FL)
binode->flags |= BTRFS_INODE_NODUMP;
else
binode->flags &= ~BTRFS_INODE_NODUMP;
if (fsflags & FS_NOATIME_FL)
binode->flags |= BTRFS_INODE_NOATIME;
else
binode->flags &= ~BTRFS_INODE_NOATIME;
if (fsflags & FS_DIRSYNC_FL)
binode->flags |= BTRFS_INODE_DIRSYNC;
else
binode->flags &= ~BTRFS_INODE_DIRSYNC;
if (fsflags & 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)
binode->flags |= BTRFS_INODE_NODATACOW
| BTRFS_INODE_NODATASUM;
} else {
binode->flags |= BTRFS_INODE_NODATACOW;
}
} else {
/*
* Revert back under same assumptions as above
*/
if (S_ISREG(mode)) {
if (inode->i_size == 0)
binode->flags &= ~(BTRFS_INODE_NODATACOW
| BTRFS_INODE_NODATASUM);
} else {
binode->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 (fsflags & FS_NOCOMP_FL) {
binode->flags &= ~BTRFS_INODE_COMPRESS;
binode->flags |= BTRFS_INODE_NOCOMPRESS;
ret = btrfs_set_prop_trans(inode, "btrfs.compression", NULL,
0, 0);
if (ret && ret != -ENODATA)
goto out_drop;
} else if (fsflags & FS_COMPR_FL) {
const char *comp;
if (IS_SWAPFILE(inode)) {
ret = -ETXTBSY;
goto out_unlock;
}
binode->flags |= BTRFS_INODE_COMPRESS;
binode->flags &= ~BTRFS_INODE_NOCOMPRESS;
comp = btrfs_compress_type2str(fs_info->compress_type);
if (!comp || comp[0] == 0)
comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
ret = btrfs_set_prop_trans(inode, "btrfs.compression", comp,
strlen(comp), 0);
if (ret)
goto out_drop;
} else {
ret = btrfs_set_prop_trans(inode, "btrfs.compression", NULL,
0, 0);
if (ret && ret != -ENODATA)
goto out_drop;
binode->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_sync_inode_flags_to_i_flags(inode);
inode_inc_iversion(inode);
inode->i_ctime = current_time(inode);
ret = btrfs_update_inode(trans, root, inode);
btrfs_end_transaction(trans);
out_drop:
if (ret) {
binode->flags = old_flags;
inode->i_flags = old_i_flags;
}
out_unlock:
inode_unlock(inode);
mnt_drop_write_file(file);
return ret;
}
/*
* Translate btrfs internal inode flags to xflags as expected by the
* FS_IOC_FSGETXATT ioctl. Filter only the supported ones, unknown flags are
* silently dropped.
*/
static unsigned int btrfs_inode_flags_to_xflags(unsigned int flags)
{
unsigned int xflags = 0;
if (flags & BTRFS_INODE_APPEND)
xflags |= FS_XFLAG_APPEND;
if (flags & BTRFS_INODE_IMMUTABLE)
xflags |= FS_XFLAG_IMMUTABLE;
if (flags & BTRFS_INODE_NOATIME)
xflags |= FS_XFLAG_NOATIME;
if (flags & BTRFS_INODE_NODUMP)
xflags |= FS_XFLAG_NODUMP;
if (flags & BTRFS_INODE_SYNC)
xflags |= FS_XFLAG_SYNC;
return xflags;
}
/* Check if @flags are a supported and valid set of FS_XFLAGS_* flags */
static int check_xflags(unsigned int flags)
{
if (flags & ~(FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE | FS_XFLAG_NOATIME |
FS_XFLAG_NODUMP | FS_XFLAG_SYNC))
return -EOPNOTSUPP;
return 0;
}
/*
* Set the xflags from the internal inode flags. The remaining items of fsxattr
* are zeroed.
*/
static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg)
{
struct btrfs_inode *binode = BTRFS_I(file_inode(file));
struct fsxattr fa;
memset(&fa, 0, sizeof(fa));
fa.fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags);
if (copy_to_user(arg, &fa, sizeof(fa)))
return -EFAULT;
return 0;
}
static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg)
{
struct inode *inode = file_inode(file);
struct btrfs_inode *binode = BTRFS_I(inode);
struct btrfs_root *root = binode->root;
struct btrfs_trans_handle *trans;
struct fsxattr fa;
unsigned old_flags;
unsigned old_i_flags;
int ret = 0;
if (!inode_owner_or_capable(inode))
return -EPERM;
if (btrfs_root_readonly(root))
return -EROFS;
memset(&fa, 0, sizeof(fa));
if (copy_from_user(&fa, arg, sizeof(fa)))
return -EFAULT;
ret = check_xflags(fa.fsx_xflags);
if (ret)
return ret;
if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0)
return -EOPNOTSUPP;
ret = mnt_want_write_file(file);
if (ret)
return ret;
inode_lock(inode);
old_flags = binode->flags;
old_i_flags = inode->i_flags;
/* We need the capabilities to change append-only or immutable inode */
if (((old_flags & (BTRFS_INODE_APPEND | BTRFS_INODE_IMMUTABLE)) ||
(fa.fsx_xflags & (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE))) &&
!capable(CAP_LINUX_IMMUTABLE)) {
ret = -EPERM;
goto out_unlock;
}
if (fa.fsx_xflags & FS_XFLAG_SYNC)
binode->flags |= BTRFS_INODE_SYNC;
else
binode->flags &= ~BTRFS_INODE_SYNC;
if (fa.fsx_xflags & FS_XFLAG_IMMUTABLE)
binode->flags |= BTRFS_INODE_IMMUTABLE;
else
binode->flags &= ~BTRFS_INODE_IMMUTABLE;
if (fa.fsx_xflags & FS_XFLAG_APPEND)
binode->flags |= BTRFS_INODE_APPEND;
else
binode->flags &= ~BTRFS_INODE_APPEND;
if (fa.fsx_xflags & FS_XFLAG_NODUMP)
binode->flags |= BTRFS_INODE_NODUMP;
else
binode->flags &= ~BTRFS_INODE_NODUMP;
if (fa.fsx_xflags & FS_XFLAG_NOATIME)
binode->flags |= BTRFS_INODE_NOATIME;
else
binode->flags &= ~BTRFS_INODE_NOATIME;
/* 1 item for the inode */
trans = btrfs_start_transaction(root, 1);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out_unlock;
}
btrfs_sync_inode_flags_to_i_flags(inode);
inode_inc_iversion(inode);
inode->i_ctime = current_time(inode);
ret = btrfs_update_inode(trans, root, inode);
btrfs_end_transaction(trans);
out_unlock:
if (ret) {
binode->flags = old_flags;
inode->i_flags = old_i_flags;
}
inode_unlock(inode);
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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_device *device;
struct request_queue *q;
struct fstrim_range range;
u64 minlen = ULLONG_MAX;
u64 num_devices = 0;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
/*
* If the fs is mounted with nologreplay, which requires it to be
* mounted in RO mode as well, we can not allow discard on free space
* inside block groups, because log trees refer to extents that are not
* pinned in a block group's free space cache (pinning the extents is
* precisely the first phase of replaying a log tree).
*/
if (btrfs_test_opt(fs_info, NOLOGREPLAY))
return -EROFS;
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_t(u64, q->limits.discard_granularity,
minlen);
}
}
rcu_read_unlock();
if (!num_devices)
return -EOPNOTSUPP;
if (copy_from_user(&range, arg, sizeof(range)))
return -EFAULT;
/*
* NOTE: Don't truncate the range using super->total_bytes. Bytenr of
* block group is in the logical address space, which can be any
* sectorsize aligned bytenr in the range [0, U64_MAX].
*/
if (range.len < fs_info->sb->s_blocksize)
return -EINVAL;
range.minlen = max(range.minlen, minlen);
ret = btrfs_trim_fs(fs_info, &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,
const char *name, int namelen,
u64 *async_transid,
struct btrfs_qgroup_inherit *inherit)
{
struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
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 timespec64 cur_time = current_time(dir);
struct inode *inode;
int ret;
int err;
u64 objectid;
u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
u64 index = 0;
uuid_le new_uuid;
root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
if (!root_item)
return -ENOMEM;
ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
if (ret)
goto fail_free;
/*
* Don't create subvolume whose level is not zero. Or qgroup will be
* screwed up since it assumes subvolume qgroup's level to be 0.
*/
if (btrfs_qgroup_level(objectid)) {
ret = -ENOSPC;
goto fail_free;
}
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, false);
if (ret)
goto fail_free;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
btrfs_subvolume_release_metadata(fs_info, &block_rsv);
goto fail_free;
}
trans->block_rsv = &block_rsv;
trans->bytes_reserved = block_rsv.size;
ret = btrfs_qgroup_inherit(trans, 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;
}
btrfs_mark_buffer_dirty(leaf);
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,
fs_info->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, fs_info->tree_root, &key,
root_item);
if (ret)
goto fail;
key.offset = (u64)-1;
new_root = btrfs_read_fs_root_no_name(fs_info, &key);
if (IS_ERR(new_root)) {
ret = PTR_ERR(new_root);
btrfs_abort_transaction(trans, 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, ret);
goto fail;
}
mutex_lock(&new_root->objectid_mutex);
new_root->highest_objectid = new_dirid;
mutex_unlock(&new_root->objectid_mutex);
/*
* insert the directory item
*/
ret = btrfs_set_inode_index(BTRFS_I(dir), &index);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto fail;
}
ret = btrfs_insert_dir_item(trans, name, namelen, BTRFS_I(dir), &key,
BTRFS_FT_DIR, index);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto fail;
}
btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
ret = btrfs_update_inode(trans, root, dir);
BUG_ON(ret);
ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
btrfs_ino(BTRFS_I(dir)), index, name, namelen);
BUG_ON(ret);
ret = btrfs_uuid_tree_add(trans, root_item->uuid,
BTRFS_UUID_KEY_SUBVOL, objectid);
if (ret)
btrfs_abort_transaction(trans, ret);
fail:
kfree(root_item);
trans->block_rsv = NULL;
trans->bytes_reserved = 0;
btrfs_subvolume_release_metadata(fs_info, &block_rsv);
if (async_transid) {
*async_transid = trans->transid;
err = btrfs_commit_transaction_async(trans, 1);
if (err)
err = btrfs_commit_transaction(trans);
} else {
err = btrfs_commit_transaction(trans);
}
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;
fail_free:
kfree(root_item);
return ret;
}
static int create_snapshot(struct btrfs_root *root, struct inode *dir,
struct dentry *dentry,
u64 *async_transid, bool readonly,
struct btrfs_qgroup_inherit *inherit)
{
struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
struct inode *inode;
struct btrfs_pending_snapshot *pending_snapshot;
struct btrfs_trans_handle *trans;
int ret;
bool snapshot_force_cow = false;
if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
return -EINVAL;
if (atomic_read(&root->nr_swapfiles)) {
btrfs_warn(fs_info,
"cannot snapshot subvolume with active swapfile");
return -ETXTBSY;
}
pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
if (!pending_snapshot)
return -ENOMEM;
pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
GFP_KERNEL);
pending_snapshot->path = btrfs_alloc_path();
if (!pending_snapshot->root_item || !pending_snapshot->path) {
ret = -ENOMEM;
goto free_pending;
}
/*
* Force new buffered writes to reserve space even when NOCOW is
* possible. This is to avoid later writeback (running dealloc) to
* fallback to COW mode and unexpectedly fail with ENOSPC.
*/
atomic_inc(&root->will_be_snapshotted);
smp_mb__after_atomic();
/* wait for no snapshot writes */
wait_event(root->subv_writers->wait,
percpu_counter_sum(&root->subv_writers->counter) == 0);
ret = btrfs_start_delalloc_snapshot(root);
if (ret)
goto dec_and_free;
/*
* All previous writes have started writeback in NOCOW mode, so now
* we force future writes to fallback to COW mode during snapshot
* creation.
*/
atomic_inc(&root->snapshot_force_cow);
snapshot_force_cow = true;
btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
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,
false);
if (ret)
goto dec_and_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(&fs_info->trans_lock);
list_add(&pending_snapshot->list,
&trans->transaction->pending_snapshots);
spin_unlock(&fs_info->trans_lock);
if (async_transid) {
*async_transid = trans->transid;
ret = btrfs_commit_transaction_async(trans, 1);
if (ret)
ret = btrfs_commit_transaction(trans);
} else {
ret = btrfs_commit_transaction(trans);
}
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(fs_info, &pending_snapshot->block_rsv);
dec_and_free:
if (snapshot_force_cow)
atomic_dec(&root->snapshot_force_cow);
if (atomic_dec_and_test(&root->will_be_snapshotted))
wake_up_var(&root->will_be_snapshotted);
free_pending:
kfree(pending_snapshot->root_item);
btrfs_free_path(pending_snapshot->path);
kfree(pending_snapshot);
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 anything 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(const struct path *parent,
const 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 btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
struct dentry *dentry;
int error;
error = down_write_killable_nested(&dir->i_rwsem, 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 = 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(&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,
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(&fs_info->subvol_sem);
out_dput:
dput(dentry);
out_unlock:
inode_unlock(dir);
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_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(BTRFS_I(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_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, &cached);
em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0);
unlock_extent_cached(io_tree, start, end, &cached);
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 > SZ_128K && next->block_len > SZ_128K))
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;
struct extent_changeset *data_reserved = NULL;
gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
file_end = (isize - 1) >> PAGE_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, &data_reserved,
start_index << PAGE_SHIFT,
page_cnt << PAGE_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_SIZE - 1;
while (1) {
lock_extent_bits(tree, page_start, page_end,
&cached_state);
ordered = btrfs_lookup_ordered_extent(inode,
page_start);
unlock_extent_cached(tree, page_start, page_end,
&cached_state);
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);
put_page(page);
goto again;
}
}
if (!PageUptodate(page)) {
btrfs_readpage(NULL, page);
lock_page(page);
if (!PageUptodate(page)) {
unlock_page(page);
put_page(page);
ret = -EIO;
break;
}
}
if (page->mapping != inode->i_mapping) {
unlock_page(page);
put_page(page);
goto again;
}
pages[i] = page;
i_done++;
}
if (!i_done || ret)
goto out;
if (!(inode->i_sb->s_flags & SB_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_SIZE;
lock_extent_bits(&BTRFS_I(inode)->io_tree,
page_start, page_end - 1, &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);
if (i_done != page_cnt) {
spin_lock(&BTRFS_I(inode)->lock);
btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
spin_unlock(&BTRFS_I(inode)->lock);
btrfs_delalloc_release_space(inode, data_reserved,
start_index << PAGE_SHIFT,
(page_cnt - i_done) << PAGE_SHIFT, true);
}
set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
&cached_state);
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
page_start, page_end - 1, &cached_state);
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]);
put_page(pages[i]);
}
btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT,
false);
extent_changeset_free(data_reserved);
return i_done;
out:
for (i = 0; i < i_done; i++) {
unlock_page(pages[i]);
put_page(pages[i]);
}
btrfs_delalloc_release_space(inode, data_reserved,
start_index << PAGE_SHIFT,
page_cnt << PAGE_SHIFT, true);
btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT,
true);
extent_changeset_free(data_reserved);
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_fs_info *fs_info = btrfs_sb(inode->i_sb);
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 = SZ_256K >> PAGE_SHIFT;
unsigned long cluster = max_cluster;
u64 new_align = ~((u64)SZ_128K - 1);
struct page **pages = NULL;
bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
if (isize == 0)
return 0;
if (range->start >= isize)
return -EINVAL;
if (do_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 = SZ_256K;
/*
* If we were not given a file, allocate a readahead context. As
* readahead is just an optimization, defrag will work without it so
* we don't error out.
*/
if (!file) {
ra = kzalloc(sizeof(*ra), GFP_KERNEL);
if (ra)
file_ra_state_init(ra, inode->i_mapping);
} else {
ra = &file->f_ra;
}
pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
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_SHIFT;
} else {
last_index = (isize - 1) >> PAGE_SHIFT;
}
if (newer_than) {
ret = find_new_extents(root, inode, newer_than,
&newer_off, SZ_64K);
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_SHIFT;
} else
goto out_ra;
} else {
i = range->start >> PAGE_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_SIZE))) {
/*
* make sure we stop running if someone unmounts
* the FS
*/
if (!(inode->i_sb->s_flags & SB_ACTIVE))
break;
if (btrfs_defrag_cancelled(fs_info)) {
btrfs_debug(fs_info, "defrag_file cancelled");
ret = -EAGAIN;
break;
}
if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
extent_thresh, &last_len, &skip,
&defrag_end, do_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_SIZE);
i = max(i + 1, next);
continue;
}
if (!newer_than) {
cluster = (PAGE_ALIGN(defrag_end) >>
PAGE_SHIFT) - i;
cluster = min(cluster, max_cluster);
} else {
cluster = max_cluster;
}
if (i + cluster > ra_index) {
ra_index = max(i, ra_index);
if (ra)
page_cache_sync_readahead(inode->i_mapping, ra,
file, ra_index, cluster);
ra_index += cluster;
}
inode_lock(inode);
if (IS_SWAPFILE(inode)) {
ret = -ETXTBSY;
} else {
if (do_compress)
BTRFS_I(inode)->defrag_compress = compress_type;
ret = cluster_pages_for_defrag(inode, pages, i, cluster);
}
if (ret < 0) {
inode_unlock(inode);
goto out_ra;
}
defrag_count += ret;
balance_dirty_pages_ratelimited(inode->i_mapping);
inode_unlock(inode);
if (newer_than) {
if (newer_off == (u64)-1)
break;
if (ret > 0)
i += ret;
newer_off = max(newer_off + 1,
(u64)i << PAGE_SHIFT);
ret = find_new_extents(root, inode, newer_than,
&newer_off, SZ_64K);
if (!ret) {
range->start = newer_off;
i = (newer_off & new_align) >> PAGE_SHIFT;
} else {
break;
}
} else {
if (ret > 0) {
i += ret;
last_len += ret << PAGE_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->compress_type == BTRFS_COMPRESS_LZO) {
btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
} else if (range->compress_type == BTRFS_COMPRESS_ZSTD) {
btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
}
ret = defrag_count;
out_ra:
if (do_compress) {
inode_lock(inode);
BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE;
inode_unlock(inode);
}
if (!file)
kfree(ra);
kfree(pages);
return ret;
}
static noinline int btrfs_ioctl_resize(struct file *file,
void __user *arg)
{
struct inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
u64 new_size;
u64 old_size;
u64 devid = 1;
struct btrfs_root *root = BTRFS_I(inode)->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 (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
mnt_drop_write_file(file);
return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
}
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(fs_info, "resizing devid %llu", devid);
}
device = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
if (!device) {
btrfs_info(fs_info, "resizer unable to find device %llu",
devid);
ret = -ENODEV;
goto out_free;
}
if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
btrfs_info(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 (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
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 < SZ_256M) {
ret = -EINVAL;
goto out_free;
}
if (new_size > device->bdev->bd_inode->i_size) {
ret = -EFBIG;
goto out_free;
}
new_size = round_down(new_size, fs_info->sectorsize);
btrfs_info_in_rcu(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);
} else if (new_size < old_size) {
ret = btrfs_shrink_device(device, new_size);
} /* equal, nothing need to do */
out_free:
kfree(vol_args);
out:
clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
mnt_drop_write_file(file);
return ret;
}
static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
const char *name, unsigned long fd, int subvol,
u64 *transid, bool readonly,
struct btrfs_qgroup_inherit *inherit)
{
int namelen;
int ret = 0;
if (!S_ISDIR(file_inode(file)->i_mode))
return -ENOTDIR;
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(file_inode(file))->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;
if (!S_ISDIR(file_inode(file)->i_mode))
return -ENOTDIR;
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;
if (!S_ISDIR(file_inode(file)->i_mode))
return -ENOTDIR;
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_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_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_root *root = BTRFS_I(inode)->root;
int ret = 0;
u64 flags = 0;
if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
return -EINVAL;
down_read(&fs_info->subvol_sem);
if (btrfs_root_readonly(root))
flags |= BTRFS_SUBVOL_RDONLY;
up_read(&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_fs_info *fs_info = btrfs_sb(inode->i_sb);
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(BTRFS_I(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(&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(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, fs_info->tree_root,
&root->root_key, &root->root_item);
if (ret < 0) {
btrfs_end_transaction(trans);
goto out_reset;
}
ret = btrfs_commit_transaction(trans);
out_reset:
if (ret)
btrfs_set_root_flags(&root->root_item, root_flags);
out_drop_sem:
up_write(&fs_info->subvol_sem);
out_drop_write:
mnt_drop_write_file(file);
out:
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_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_fs_info *info = btrfs_sb(inode->i_sb);
struct btrfs_root *root;
struct btrfs_key key;
struct btrfs_path *path;
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_free_path(path);
return PTR_ERR(root);
}
}
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(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 = SZ_16M;
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;
/* 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 __user *)(&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 - 1];
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)) {
ret = PTR_ERR(root);
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 int btrfs_search_path_in_tree_user(struct inode *inode,
struct btrfs_ioctl_ino_lookup_user_args *args)
{
struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
struct super_block *sb = inode->i_sb;
struct btrfs_key upper_limit = BTRFS_I(inode)->location;
u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
u64 dirid = args->dirid;
unsigned long item_off;
unsigned long item_len;
struct btrfs_inode_ref *iref;
struct btrfs_root_ref *rref;
struct btrfs_root *root;
struct btrfs_path *path;
struct btrfs_key key, key2;
struct extent_buffer *leaf;
struct inode *temp_inode;
char *ptr;
int slot;
int len;
int total_len = 0;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
/*
* If the bottom subvolume does not exist directly under upper_limit,
* construct the path in from the bottom up.
*/
if (dirid != upper_limit.objectid) {
ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
key.objectid = treeid;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
root = btrfs_read_fs_root_no_name(fs_info, &key);
if (IS_ERR(root)) {
ret = PTR_ERR(root);
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;
}
}
leaf = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(leaf, &key, slot);
iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
len = btrfs_inode_ref_name_len(leaf, iref);
ptr -= len + 1;
total_len += len + 1;
if (ptr < args->path) {
ret = -ENAMETOOLONG;
goto out;
}
*(ptr + len) = '/';
read_extent_buffer(leaf, ptr,
(unsigned long)(iref + 1), len);
/* Check the read+exec permission of this directory */
ret = btrfs_previous_item(root, path, dirid,
BTRFS_INODE_ITEM_KEY);
if (ret < 0) {
goto out;
} else if (ret > 0) {
ret = -ENOENT;
goto out;
}
leaf = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(leaf, &key2, slot);
if (key2.objectid != dirid) {
ret = -ENOENT;
goto out;
}
temp_inode = btrfs_iget(sb, &key2, root, NULL);
if (IS_ERR(temp_inode)) {
ret = PTR_ERR(temp_inode);
goto out;
}
ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
iput(temp_inode);
if (ret) {
ret = -EACCES;
goto out;
}
if (key.offset == upper_limit.objectid)
break;
if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
ret = -EACCES;
goto out;
}
btrfs_release_path(path);
key.objectid = key.offset;
key.offset = (u64)-1;
dirid = key.objectid;
}
memmove(args->path, ptr, total_len);
args->path[total_len] = '\0';
btrfs_release_path(path);
}
/* Get the bottom subvolume's name from ROOT_REF */
root = fs_info->tree_root;
key.objectid = treeid;
key.type = BTRFS_ROOT_REF_KEY;
key.offset = args->treeid;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0) {
goto out;
} else if (ret > 0) {
ret = -ENOENT;
goto out;
}
leaf = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(leaf, &key, slot);
item_off = btrfs_item_ptr_offset(leaf, slot);
item_len = btrfs_item_size_nr(leaf, slot);
/* Check if dirid in ROOT_REF corresponds to passed dirid */
rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
ret = -EINVAL;
goto out;
}
/* Copy subvolume's name */
item_off += sizeof(struct btrfs_root_ref);
item_len -= sizeof(struct btrfs_root_ref);
read_extent_buffer(leaf, args->name, item_off, item_len);
args->name[item_len] = 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;
}
/*
* Version of ino_lookup ioctl (unprivileged)
*
* The main differences from ino_lookup ioctl are:
*
* 1. Read + Exec permission will be checked using inode_permission() during
* path construction. -EACCES will be returned in case of failure.
* 2. Path construction will be stopped at the inode number which corresponds
* to the fd with which this ioctl is called. If constructed path does not
* exist under fd's inode, -EACCES will be returned.
* 3. The name of bottom subvolume is also searched and filled.
*/
static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
{
struct btrfs_ioctl_ino_lookup_user_args *args;
struct inode *inode;
int ret;
args = memdup_user(argp, sizeof(*args));
if (IS_ERR(args))
return PTR_ERR(args);
inode = file_inode(file);
if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
/*
* The subvolume does not exist under fd with which this is
* called
*/
kfree(args);
return -EACCES;
}
ret = btrfs_search_path_in_tree_user(inode, args);
if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
ret = -EFAULT;
kfree(args);
return ret;
}
/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp)
{
struct btrfs_ioctl_get_subvol_info_args *subvol_info;
struct btrfs_fs_info *fs_info;
struct btrfs_root *root;
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_root_item *root_item;
struct btrfs_root_ref *rref;
struct extent_buffer *leaf;
unsigned long item_off;
unsigned long item_len;
struct inode *inode;
int slot;
int ret = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
if (!subvol_info) {
btrfs_free_path(path);
return -ENOMEM;
}
inode = file_inode(file);
fs_info = BTRFS_I(inode)->root->fs_info;
/* Get root_item of inode's subvolume */
key.objectid = BTRFS_I(inode)->root->root_key.objectid;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
root = btrfs_read_fs_root_no_name(fs_info, &key);
if (IS_ERR(root)) {
ret = PTR_ERR(root);
goto out;
}
root_item = &root->root_item;
subvol_info->treeid = key.objectid;
subvol_info->generation = btrfs_root_generation(root_item);
subvol_info->flags = btrfs_root_flags(root_item);
memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
BTRFS_UUID_SIZE);
memcpy(subvol_info->received_uuid, root_item->received_uuid,
BTRFS_UUID_SIZE);
subvol_info->ctransid = btrfs_root_ctransid(root_item);
subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
subvol_info->otransid = btrfs_root_otransid(root_item);
subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
subvol_info->stransid = btrfs_root_stransid(root_item);
subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
subvol_info->rtransid = btrfs_root_rtransid(root_item);
subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
/* Search root tree for ROOT_BACKREF of this subvolume */
root = fs_info->tree_root;
key.type = BTRFS_ROOT_BACKREF_KEY;
key.offset = 0;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0) {
goto out;
} else if (path->slots[0] >=
btrfs_header_nritems(path->nodes[0])) {
ret = btrfs_next_leaf(root, path);
if (ret < 0) {
goto out;
} else if (ret > 0) {
ret = -EUCLEAN;
goto out;
}
}
leaf = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(leaf, &key, slot);
if (key.objectid == subvol_info->treeid &&
key.type == BTRFS_ROOT_BACKREF_KEY) {
subvol_info->parent_id = key.offset;
rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
item_off = btrfs_item_ptr_offset(leaf, slot)
+ sizeof(struct btrfs_root_ref);
item_len = btrfs_item_size_nr(leaf, slot)
- sizeof(struct btrfs_root_ref);
read_extent_buffer(leaf, subvol_info->name,
item_off, item_len);
} else {
ret = -ENOENT;
goto out;
}
}
if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
ret = -EFAULT;
out:
btrfs_free_path(path);
kzfree(subvol_info);
return ret;
}
/*
* Return ROOT_REF information of the subvolume containing this inode
* except the subvolume name.
*/
static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp)
{
struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
struct btrfs_root_ref *rref;
struct btrfs_root *root;
struct btrfs_path *path;
struct btrfs_key key;
struct extent_buffer *leaf;
struct inode *inode;
u64 objectid;
int slot;
int ret;
u8 found;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
rootrefs = memdup_user(argp, sizeof(*rootrefs));
if (IS_ERR(rootrefs)) {
btrfs_free_path(path);
return PTR_ERR(rootrefs);
}
inode = file_inode(file);
root = BTRFS_I(inode)->root->fs_info->tree_root;
objectid = BTRFS_I(inode)->root->root_key.objectid;
key.objectid = objectid;
key.type = BTRFS_ROOT_REF_KEY;
key.offset = rootrefs->min_treeid;
found = 0;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0) {
goto out;
} else if (path->slots[0] >=
btrfs_header_nritems(path->nodes[0])) {
ret = btrfs_next_leaf(root, path);
if (ret < 0) {
goto out;
} else if (ret > 0) {
ret = -EUCLEAN;
goto out;
}
}
while (1) {
leaf = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(leaf, &key, slot);
if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
ret = 0;
goto out;
}
if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
ret = -EOVERFLOW;
goto out;
}
rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
rootrefs->rootref[found].treeid = key.offset;
rootrefs->rootref[found].dirid =
btrfs_root_ref_dirid(leaf, rref);
found++;
ret = btrfs_next_item(root, path);
if (ret < 0) {
goto out;
} else if (ret > 0) {
ret = -EUCLEAN;
goto out;
}
}
out:
if (!ret || ret == -EOVERFLOW) {
rootrefs->num_items = found;
/* update min_treeid for next search */
if (found)
rootrefs->min_treeid =
rootrefs->rootref[found - 1].treeid + 1;
if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
ret = -EFAULT;
}
kfree(rootrefs);
btrfs_free_path(path);
return ret;
}
static noinline int btrfs_ioctl_snap_destroy(struct file *file,
void __user *arg)
{
struct dentry *parent = file->f_path.dentry;
struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
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;
int namelen;
int err = 0;
if (!S_ISDIR(dir->i_mode))
return -ENOTDIR;
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 = down_write_killable_nested(&dir->i_rwsem, 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(fs_info, 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(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
err = -EINVAL;
goto out_dput;
}
inode_lock(inode);
err = btrfs_delete_subvolume(dir, dentry);
inode_unlock(inode);
if (!err)
d_delete(dentry);
out_dput:
dput(dentry);
out_unlock_dir:
inode_unlock(dir);
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);
break;
case S_IFREG:
/*
* Note that this does not check the file descriptor for write
* access. This prevents defragmenting executables that are
* running and allows defrag on files open in read-only mode.
*/
if (!capable(CAP_SYS_ADMIN) &&
inode_permission(inode, MAY_WRITE)) {
ret = -EPERM;
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, BTRFS_OLDEST_GENERATION, 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_fs_info *fs_info, void __user *arg)
{
struct btrfs_ioctl_vol_args *vol_args;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags))
return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
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(fs_info, vol_args->name);
if (!ret)
btrfs_info(fs_info, "disk added %s", vol_args->name);
kfree(vol_args);
out:
clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
return ret;
}
static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
{
struct inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_ioctl_vol_args_v2 *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;
}
/* Check for compatibility reject unknown flags */
if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED) {
ret = -EOPNOTSUPP;
goto out;
}
if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
goto out;
}
if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
} else {
vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
ret = btrfs_rm_device(fs_info, vol_args->name, 0);
}
clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
if (!ret) {
if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
btrfs_info(fs_info, "device deleted: id %llu",
vol_args->devid);
else
btrfs_info(fs_info, "device deleted: %s",
vol_args->name);
}
out:
kfree(vol_args);
err_drop:
mnt_drop_write_file(file);
return ret;
}
static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
{
struct inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
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;
if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
goto out_drop_write;
}
vol_args = memdup_user(arg, sizeof(*vol_args));
if (IS_ERR(vol_args)) {
ret = PTR_ERR(vol_args);
goto out;
}
vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
ret = btrfs_rm_device(fs_info, vol_args->name, 0);
if (!ret)
btrfs_info(fs_info, "disk deleted %s", vol_args->name);
kfree(vol_args);
out:
clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
out_drop_write:
mnt_drop_write_file(file);
return ret;
}
static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
void __user *arg)
{
struct btrfs_ioctl_fs_info_args *fi_args;
struct btrfs_device *device;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
int ret = 0;
fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
if (!fi_args)
return -ENOMEM;
rcu_read_lock();
fi_args->num_devices = fs_devices->num_devices;
list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
if (device->devid > fi_args->max_id)
fi_args->max_id = device->devid;
}
rcu_read_unlock();
memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
fi_args->nodesize = fs_info->nodesize;
fi_args->sectorsize = fs_info->sectorsize;
fi_args->clone_alignment = fs_info->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_fs_info *fs_info,
void __user *arg)
{
struct btrfs_ioctl_dev_info_args *di_args;
struct btrfs_device *dev;
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;
rcu_read_lock();
dev = btrfs_find_device(fs_info->fs_devices, di_args->devid, s_uuid,
NULL, true);
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) {
strncpy(di_args->path, rcu_str_deref(dev->name),
sizeof(di_args->path) - 1);
di_args->path[sizeof(di_args->path) - 1] = 0;
} else {
di_args->path[0] = '\0';
}
out:
rcu_read_unlock();
if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
ret = -EFAULT;
kfree(di_args);
return ret;
}
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);
} else if (inode1 == inode2 && loff2 < loff1) {
swap(loff1, loff2);
}
lock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
lock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
}
static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 len,
struct inode *dst, u64 dst_loff)
{
int ret;
/*
* Lock destination range to serialize with concurrent readpages() and
* source range to serialize with relocation.
*/
btrfs_double_extent_lock(src, loff, dst, dst_loff, len);
ret = btrfs_clone(src, dst, loff, len, len, dst_loff, 1);
btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
return ret;
}
#define BTRFS_MAX_DEDUPE_LEN SZ_16M
static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
struct inode *dst, u64 dst_loff)
{
int ret;
u64 i, tail_len, chunk_count;
tail_len = olen % BTRFS_MAX_DEDUPE_LEN;
chunk_count = div_u64(olen, BTRFS_MAX_DEDUPE_LEN);
for (i = 0; i < chunk_count; i++) {
ret = btrfs_extent_same_range(src, loff, BTRFS_MAX_DEDUPE_LEN,
dst, dst_loff);
if (ret)
return ret;
loff += BTRFS_MAX_DEDUPE_LEN;
dst_loff += BTRFS_MAX_DEDUPE_LEN;
}
if (tail_len > 0)
ret = btrfs_extent_same_range(src, loff, tail_len, dst,
dst_loff);
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(inode);
/*
* 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(BTRFS_I(inode), endoff);
ret = btrfs_update_inode(trans, root, inode);
if (ret) {
btrfs_abort_transaction(trans, ret);
btrfs_end_transaction(trans);
goto out;
}
ret = btrfs_end_transaction(trans);
out:
return ret;
}
static void clone_update_extent_map(struct btrfs_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 = &inode->extent_tree;
struct extent_map *em;
int ret;
em = alloc_extent_map();
if (!em) {
set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &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,
&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, &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 *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_fs_info *fs_info = btrfs_sb(dst->i_sb);
struct btrfs_root *root = BTRFS_I(dst)->root;
const u64 aligned_end = ALIGN(new_key->offset + datal,
fs_info->sectorsize);
int ret;
struct btrfs_key key;
if (new_key->offset > 0)
return -EOPNOTSUPP;
key.objectid = btrfs_ino(BTRFS_I(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(BTRFS_I(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(BTRFS_I(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_fs_info *fs_info = btrfs_sb(inode->i_sb);
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 = kvmalloc(fs_info->nodesize, GFP_KERNEL);
if (!buf)
return ret;
path = btrfs_alloc_path();
if (!path) {
kvfree(buf);
return ret;
}
path->reada = READA_FORWARD;
/* clone data */
key.objectid = btrfs_ino(BTRFS_I(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(BTRFS_I(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(BTRFS_I(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,
ret);
btrfs_end_transaction(trans);
goto out;
}
ret = btrfs_insert_empty_item(trans, root, path,
&new_key, size);
if (ret) {
btrfs_abort_transaction(trans, ret);
btrfs_end_transaction(trans);
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(BTRFS_I(inode)),
new_key.offset - datao);
if (ret) {
btrfs_abort_transaction(trans,
ret);
btrfs_end_transaction(trans);
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);
goto out;
}
size -= skip + trim;
datal -= skip + trim;
ret = clone_copy_inline_extent(inode,
trans, path,
&new_key,
drop_start,
datal,
skip, size, buf);
if (ret) {
if (ret != -EOPNOTSUPP)
btrfs_abort_transaction(trans,
ret);
btrfs_end_transaction(trans);
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(BTRFS_I(inode), trans,
NULL, drop_start,
new_key.offset - drop_start);
clone_update_extent_map(BTRFS_I(inode), trans,
path, 0, 0);
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(path);
last_dest_end = ALIGN(new_key.offset + datal,
fs_info->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;
if (fatal_signal_pending(current)) {
ret = -EINTR;
goto out;
}
}
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, ret);
btrfs_end_transaction(trans);
goto out;
}
clone_update_extent_map(BTRFS_I(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);
kvfree(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_fs_info *fs_info = btrfs_sb(inode->i_sb);
int ret;
u64 len = olen;
u64 bs = fs_info->sb->s_blocksize;
/*
* 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.
*/
/*
* VFS's generic_remap_file_range_prep() protects us from cloning the
* eof block into the middle of a file, which would result in corruption
* if the file size is not blocksize aligned. So we don't need to check
* for that case here.
*/
if (off + len == src->i_size)
len = ALIGN(src->i_size, bs) - off;
if (destoff > inode->i_size) {
const u64 wb_start = ALIGN_DOWN(inode->i_size, bs);
ret = btrfs_cont_expand(inode, inode->i_size, destoff);
if (ret)
return ret;
/*
* We may have truncated the last block if the inode's size is
* not sector size aligned, so we need to wait for writeback to
* complete before proceeding further, otherwise we can race
* with cloning and attempt to increment a reference to an
* extent that no longer exists (writeback completed right after
* we found the previous extent covering eof and before we
* attempted to increment its reference count).
*/
ret = btrfs_wait_ordered_range(inode, wb_start,
destoff - wb_start);
if (ret)
return ret;
}
/*
* Lock destination range to serialize with concurrent readpages() and
* source range to serialize with relocation.
*/
btrfs_double_extent_lock(src, off, inode, destoff, len);
ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
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,
round_down(destoff, PAGE_SIZE),
round_up(destoff + len, PAGE_SIZE) - 1);
return ret;
}
static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
loff_t *len, unsigned int remap_flags)
{
struct inode *inode_in = file_inode(file_in);
struct inode *inode_out = file_inode(file_out);
u64 bs = BTRFS_I(inode_out)->root->fs_info->sb->s_blocksize;
bool same_inode = inode_out == inode_in;
u64 wb_len;
int ret;
if (!(remap_flags & REMAP_FILE_DEDUP)) {
struct btrfs_root *root_out = BTRFS_I(inode_out)->root;
if (btrfs_root_readonly(root_out))
return -EROFS;
if (file_in->f_path.mnt != file_out->f_path.mnt ||
inode_in->i_sb != inode_out->i_sb)
return -EXDEV;
}
/* don't make the dst file partly checksummed */
if ((BTRFS_I(inode_in)->flags & BTRFS_INODE_NODATASUM) !=
(BTRFS_I(inode_out)->flags & BTRFS_INODE_NODATASUM)) {
return -EINVAL;
}
/*
* Now that the inodes are locked, we need to start writeback ourselves
* and can not rely on the writeback from the VFS's generic helper
* generic_remap_file_range_prep() because:
*
* 1) For compression we must call filemap_fdatawrite_range() range
* twice (btrfs_fdatawrite_range() does it for us), and the generic
* helper only calls it once;
*
* 2) filemap_fdatawrite_range(), called by the generic helper only
* waits for the writeback to complete, i.e. for IO to be done, and
* not for the ordered extents to complete. We need to wait for them
* to complete so that new file extent items are in the fs tree.
*/
if (*len == 0 && !(remap_flags & REMAP_FILE_DEDUP))
wb_len = ALIGN(inode_in->i_size, bs) - ALIGN_DOWN(pos_in, bs);
else
wb_len = ALIGN(*len, bs);
/*
* Since we don't lock ranges, wait for ongoing lockless dio writes (as
* any in progress could create its ordered extents after we wait for
* existing ordered extents below).
*/
inode_dio_wait(inode_in);
if (!same_inode)
inode_dio_wait(inode_out);
ret = btrfs_wait_ordered_range(inode_in, ALIGN_DOWN(pos_in, bs),
wb_len);
if (ret < 0)
return ret;
ret = btrfs_wait_ordered_range(inode_out, ALIGN_DOWN(pos_out, bs),
wb_len);
if (ret < 0)
return ret;
return generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out,
len, remap_flags);
}
loff_t btrfs_remap_file_range(struct file *src_file, loff_t off,
struct file *dst_file, loff_t destoff, loff_t len,
unsigned int remap_flags)
{
struct inode *src_inode = file_inode(src_file);
struct inode *dst_inode = file_inode(dst_file);
bool same_inode = dst_inode == src_inode;
int ret;
if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
return -EINVAL;
if (same_inode)
inode_lock(src_inode);
else
lock_two_nondirectories(src_inode, dst_inode);
ret = btrfs_remap_file_range_prep(src_file, off, dst_file, destoff,
&len, remap_flags);
if (ret < 0 || len == 0)
goto out_unlock;
if (remap_flags & REMAP_FILE_DEDUP)
ret = btrfs_extent_same(src_inode, off, len, dst_inode, destoff);
else
ret = btrfs_clone_files(dst_file, src_file, off, len, destoff);
out_unlock:
if (same_inode)
inode_unlock(src_inode);
else
unlock_two_nondirectories(src_inode, dst_inode);
return ret < 0 ? ret : len;
}
static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
{
struct inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
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(fs_info, &location);
if (IS_ERR(new_root)) {
ret = PTR_ERR(new_root);
goto out;
}
if (!is_fstree(new_root->root_key.objectid)) {
ret = -ENOENT;
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(fs_info->super_copy);
di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
dir_id, "default", 7, 1);
if (IS_ERR_OR_NULL(di)) {
btrfs_free_path(path);
btrfs_end_transaction(trans);
btrfs_err(fs_info,
"Umm, you don't have the default diritem, 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(fs_info, DEFAULT_SUBVOL);
btrfs_end_transaction(trans);
out:
mnt_drop_write_file(file);
return ret;
}
static void get_block_group_info(struct list_head *groups_list,
struct btrfs_ioctl_space_info *space)
{
struct btrfs_block_group_cache *block_group;
space->total_bytes = 0;
space->used_bytes = 0;
space->flags = 0;
list_for_each_entry(block_group, groups_list, list) {
space->flags = block_group->flags;
space->total_bytes += block_group->key.offset;
space->used_bytes +=
btrfs_block_group_used(&block_group->item);
}
}
static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
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;
static const 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, &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_SIZE)
return -ENOMEM;
space_args.total_spaces = 0;
dest = kmalloc(alloc_size, GFP_KERNEL);
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, &fs_info->space_info,
list) {
if (tmp->flags == types[i]) {
info = tmp;
break;
}
}
rcu_read_unlock();
if (!info)
continue;
down_read(&info->groups_sem);
for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
if (!list_empty(&info->block_groups[c])) {
get_block_group_info(&info->block_groups[c],
&space);
memcpy(dest, &space, sizeof(space));
dest++;
space_args.total_spaces++;
slot_count--;
}
if (!slot_count)
break;
}
up_read(&info->groups_sem);
}
/*
* Add global block reserve
*/
if (slot_count) {
struct btrfs_block_rsv *block_rsv = &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;
}
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, 0);
if (ret) {
btrfs_end_transaction(trans);
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_fs_info *fs_info,
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(fs_info, transid);
}
static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
{
struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
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(fs_info, sa->devid, sa->start, sa->end,
&sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
0);
if (ret == 0 && 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_fs_info *fs_info)
{
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
return btrfs_scrub_cancel(fs_info);
}
static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
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(fs_info, sa->devid, &sa->progress);
if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
ret = -EFAULT;
kfree(sa);
return ret;
}
static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
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(fs_info, sa);
if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
ret = -EFAULT;
kfree(sa);
return ret;
}
static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
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 (sb_rdonly(fs_info->sb)) {
ret = -EROFS;
goto out;
}
if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
} else {
ret = btrfs_dev_replace_by_ioctl(fs_info, p);
clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
}
break;
case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
btrfs_dev_replace_status(fs_info, p);
ret = 0;
break;
case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
p->result = btrfs_dev_replace_cancel(fs_info);
ret = 0;
break;
default:
ret = -EINVAL;
break;
}
if ((ret == 0 || ret == -ECANCELED) && 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 __user *)(unsigned long)ipa->fspath,
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_fs_info *fs_info,
void __user *arg, int version)
{
int ret = 0;
int size;
struct btrfs_ioctl_logical_ino_args *loi;
struct btrfs_data_container *inodes = NULL;
struct btrfs_path *path = NULL;
bool ignore_offset;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
loi = memdup_user(arg, sizeof(*loi));
if (IS_ERR(loi))
return PTR_ERR(loi);
if (version == 1) {
ignore_offset = false;
size = min_t(u32, loi->size, SZ_64K);
} else {
/* All reserved bits must be 0 for now */
if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
ret = -EINVAL;
goto out_loi;
}
/* Only accept flags we have defined so far */
if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
ret = -EINVAL;
goto out_loi;
}
ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
size = min_t(u32, loi->size, SZ_16M);
}
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto out;
}
inodes = init_data_container(size);
if (IS_ERR(inodes)) {
ret = PTR_ERR(inodes);
inodes = NULL;
goto out;
}
ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
build_ino_list, inodes, ignore_offset);
if (ret == -EINVAL)
ret = -ENOENT;
if (ret < 0)
goto out;
ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
size);
if (ret)
ret = -EFAULT;
out:
btrfs_free_path(path);
kvfree(inodes);
out_loi:
kfree(loi);
return ret;
}
void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
struct btrfs_ioctl_balance_args *bargs)
{
struct btrfs_balance_control *bctl = fs_info->balance_ctl;
bargs->flags = bctl->flags;
if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
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));
spin_lock(&fs_info->balance_lock);
memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
spin_unlock(&fs_info->balance_lock);
}
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 (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
mutex_lock(&fs_info->balance_mutex);
need_unlock = true;
goto locked;
}
/*
* mut. excl. ops lock is locked. Three possibilities:
* (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 (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
mutex_unlock(&fs_info->balance_mutex);
/*
* Lock released to allow other waiters to continue,
* we'll reexamine the status again.
*/
mutex_lock(&fs_info->balance_mutex);
if (fs_info->balance_ctl &&
!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
/* this is (3) */
need_unlock = false;
goto locked;
}
mutex_unlock(&fs_info->balance_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(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags));
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_KERNEL);
if (!bctl) {
ret = -ENOMEM;
goto out_bargs;
}
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 filesystem flag BTRFS_FS_EXCL_OP goes to
* btrfs_balance. bctl is freed in reset_balance_state, or, if
* restriper was paused all the way until unmount, in free_fs_info.
* The flag should be cleared after reset_balance_state.
*/
need_unlock = false;
ret = btrfs_balance(fs_info, bctl, bargs);
bctl = NULL;
if ((ret == 0 || ret == -ECANCELED) && 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);
if (need_unlock)
clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
out:
mnt_drop_write_file(file);
return ret;
}
static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
{
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
switch (cmd) {
case BTRFS_BALANCE_CTL_PAUSE:
return btrfs_pause_balance(fs_info);
case BTRFS_BALANCE_CTL_CANCEL:
return btrfs_cancel_balance(fs_info);
}
return -EINVAL;
}
static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
void __user *arg)
{
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_KERNEL);
if (!bargs) {
ret = -ENOMEM;
goto out;
}
btrfs_update_ioctl_balance_args(fs_info, 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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_ioctl_quota_ctl_args *sa;
int ret;
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(&fs_info->subvol_sem);
switch (sa->cmd) {
case BTRFS_QUOTA_CTL_ENABLE:
ret = btrfs_quota_enable(fs_info);
break;
case BTRFS_QUOTA_CTL_DISABLE:
ret = btrfs_quota_disable(fs_info);
break;
default:
ret = -EINVAL;
break;
}
kfree(sa);
up_write(&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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_root *root = BTRFS_I(inode)->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;
}
if (sa->assign) {
ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
} else {
ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
}
/* update qgroup status and info */
err = btrfs_run_qgroups(trans);
if (err < 0)
btrfs_handle_fs_error(fs_info, err,
"failed to update qgroup status and info");
err = btrfs_end_transaction(trans);
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 inode *inode = file_inode(file);
struct btrfs_root *root = BTRFS_I(inode)->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;
}
if (sa->create) {
ret = btrfs_create_qgroup(trans, sa->qgroupid);
} else {
ret = btrfs_remove_qgroup(trans, sa->qgroupid);
}
err = btrfs_end_transaction(trans);
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 inode *inode = file_inode(file);
struct btrfs_root *root = BTRFS_I(inode)->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;
}
ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
err = btrfs_end_transaction(trans);
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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
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(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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_ioctl_quota_rescan_args *qsa;
int ret = 0;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
if (!qsa)
return -ENOMEM;
if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
qsa->flags = 1;
qsa->progress = 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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
return btrfs_qgroup_wait_for_completion(fs_info, true);
}
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_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_root_item *root_item = &root->root_item;
struct btrfs_trans_handle *trans;
struct timespec64 ct = current_time(inode);
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(&fs_info->subvol_sem);
if (btrfs_ino(BTRFS_I(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)) {
ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
BTRFS_UUID_KEY_RECEIVED_SUBVOL,
root->root_key.objectid);
if (ret && ret != -ENOENT) {
btrfs_abort_transaction(trans, ret);
btrfs_end_transaction(trans);
goto out;
}
}
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, fs_info->tree_root,
&root->root_key, &root->root_item);
if (ret < 0) {
btrfs_end_transaction(trans);
goto out;
}
if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
ret = btrfs_uuid_tree_add(trans, sa->uuid,
BTRFS_UUID_KEY_RECEIVED_SUBVOL,
root->root_key.objectid);
if (ret < 0 && ret != -EEXIST) {
btrfs_abort_transaction(trans, ret);
btrfs_end_transaction(trans);
goto out;
}
}
ret = btrfs_commit_transaction(trans);
out:
up_write(&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))
return PTR_ERR(args32);
args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
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))
return PTR_ERR(sa);
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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
size_t len;
int ret;
char label[BTRFS_LABEL_SIZE];
spin_lock(&fs_info->super_lock);
memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
spin_unlock(&fs_info->super_lock);
len = strnlen(label, BTRFS_LABEL_SIZE);
if (len == BTRFS_LABEL_SIZE) {
btrfs_warn(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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_super_block *super_block = 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(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(&fs_info->super_lock);
strcpy(super_block->label, label);
spin_unlock(&fs_info->super_lock);
ret = btrfs_commit_transaction(trans);
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 }
int btrfs_ioctl_get_supported_features(void __user *arg)
{
static const 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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_super_block *super_block = 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_fs_info *fs_info,
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(fs_info,
"this kernel does not support the %s feature bit%s",
names, strchr(names, ',') ? "s" : "");
kfree(names);
} else
btrfs_warn(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(fs_info,
"can't set the %s feature bit%s while mounted",
names, strchr(names, ',') ? "s" : "");
kfree(names);
} else
btrfs_warn(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(fs_info,
"can't clear the %s feature bit%s while mounted",
names, strchr(names, ',') ? "s" : "");
kfree(names);
} else
btrfs_warn(fs_info,
"can't clear %s bits 0x%llx while mounted",
type, disallowed);
return -EPERM;
}
return 0;
}
#define check_feature(fs_info, change_mask, flags, mask_base) \
check_feature_bits(fs_info, 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 inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_super_block *super_block = 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(fs_info, flags[0].compat_flags,
flags[1].compat_flags, COMPAT);
if (ret)
return ret;
ret = check_feature(fs_info, flags[0].compat_ro_flags,
flags[1].compat_ro_flags, COMPAT_RO);
if (ret)
return ret;
ret = check_feature(fs_info, flags[0].incompat_flags,
flags[1].incompat_flags, INCOMPAT);
if (ret)
return ret;
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_drop_write;
}
spin_lock(&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(&fs_info->super_lock);
ret = btrfs_commit_transaction(trans);
out_drop_write:
mnt_drop_write_file(file);
return ret;
}
static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
{
struct btrfs_ioctl_send_args *arg;
int ret;
if (compat) {
#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
struct btrfs_ioctl_send_args_32 args32;
ret = copy_from_user(&args32, argp, sizeof(args32));
if (ret)
return -EFAULT;
arg = kzalloc(sizeof(*arg), GFP_KERNEL);
if (!arg)
return -ENOMEM;
arg->send_fd = args32.send_fd;
arg->clone_sources_count = args32.clone_sources_count;
arg->clone_sources = compat_ptr(args32.clone_sources);
arg->parent_root = args32.parent_root;
arg->flags = args32.flags;
memcpy(arg->reserved, args32.reserved,
sizeof(args32.reserved));
#else
return -ENOTTY;
#endif
} else {
arg = memdup_user(argp, sizeof(*arg));
if (IS_ERR(arg))
return PTR_ERR(arg);
}
ret = btrfs_ioctl_send(file, arg);
kfree(arg);
return ret;
}
long btrfs_ioctl(struct file *file, unsigned int
cmd, unsigned long arg)
{
struct inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_root *root = BTRFS_I(inode)->root;
void __user *argp = (void __user *)arg;
switch (cmd) {
case FS_IOC_GETFLAGS:
return btrfs_ioctl_getflags(file, argp);
case FS_IOC_SETFLAGS:
return btrfs_ioctl_setflags(file, argp);
case FS_IOC_GETVERSION:
return btrfs_ioctl_getversion(file, argp);
case FITRIM:
return btrfs_ioctl_fitrim(file, argp);
case BTRFS_IOC_SNAP_CREATE:
return btrfs_ioctl_snap_create(file, argp, 0);
case BTRFS_IOC_SNAP_CREATE_V2:
return btrfs_ioctl_snap_create_v2(file, argp, 0);
case BTRFS_IOC_SUBVOL_CREATE:
return btrfs_ioctl_snap_create(file, argp, 1);
case BTRFS_IOC_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(fs_info, argp);
case BTRFS_IOC_RM_DEV:
return btrfs_ioctl_rm_dev(file, argp);
case BTRFS_IOC_RM_DEV_V2:
return btrfs_ioctl_rm_dev_v2(file, argp);
case BTRFS_IOC_FS_INFO:
return btrfs_ioctl_fs_info(fs_info, argp);
case BTRFS_IOC_DEV_INFO:
return btrfs_ioctl_dev_info(fs_info, argp);
case BTRFS_IOC_BALANCE:
return btrfs_ioctl_balance(file, NULL);
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(fs_info, argp, 1);
case BTRFS_IOC_LOGICAL_INO_V2:
return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
case BTRFS_IOC_SPACE_INFO:
return btrfs_ioctl_space_info(fs_info, argp);
case BTRFS_IOC_SYNC: {
int ret;
ret = btrfs_start_delalloc_roots(fs_info, -1);
if (ret)
return ret;
ret = btrfs_sync_fs(inode->i_sb, 1);
/*
* The transaction thread may want to do more work,
* namely it pokes the cleaner kthread that will start
* processing uncleaned subvols.
*/
wake_up_process(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(fs_info, argp);
case BTRFS_IOC_SCRUB:
return btrfs_ioctl_scrub(file, argp);
case BTRFS_IOC_SCRUB_CANCEL:
return btrfs_ioctl_scrub_cancel(fs_info);
case BTRFS_IOC_SCRUB_PROGRESS:
return btrfs_ioctl_scrub_progress(fs_info, argp);
case BTRFS_IOC_BALANCE_V2:
return btrfs_ioctl_balance(file, argp);
case BTRFS_IOC_BALANCE_CTL:
return btrfs_ioctl_balance_ctl(fs_info, arg);
case BTRFS_IOC_BALANCE_PROGRESS:
return btrfs_ioctl_balance_progress(fs_info, 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, false);
#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
case BTRFS_IOC_SEND_32:
return _btrfs_ioctl_send(file, argp, true);
#endif
case BTRFS_IOC_GET_DEV_STATS:
return btrfs_ioctl_get_dev_stats(fs_info, 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(fs_info, 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_GET_SUPPORTED_FEATURES:
return btrfs_ioctl_get_supported_features(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);
case FS_IOC_FSGETXATTR:
return btrfs_ioctl_fsgetxattr(file, argp);
case FS_IOC_FSSETXATTR:
return btrfs_ioctl_fssetxattr(file, argp);
case BTRFS_IOC_GET_SUBVOL_INFO:
return btrfs_ioctl_get_subvol_info(file, argp);
case BTRFS_IOC_GET_SUBVOL_ROOTREF:
return btrfs_ioctl_get_subvol_rootref(file, argp);
case BTRFS_IOC_INO_LOOKUP_USER:
return btrfs_ioctl_ino_lookup_user(file, argp);
}
return -ENOTTY;
}
#ifdef CONFIG_COMPAT
long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
/*
* These all access 32-bit values anyway so no further
* handling is necessary.
*/
switch (cmd) {
case FS_IOC32_GETFLAGS:
cmd = FS_IOC_GETFLAGS;
break;
case FS_IOC32_SETFLAGS:
cmd = FS_IOC_SETFLAGS;
break;
case FS_IOC32_GETVERSION:
cmd = FS_IOC_GETVERSION;
break;
}
return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
}
#endif
Reference in New Issue View Git Blame Copy Permalink