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9452e93e6d
linux/fs/btrfs/ioctl.c
Christian Brauner 9452e93e6d
fs: port privilege checking helpers to mnt_idmap 
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:29 +01:00

4704 lines
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// 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 <linux/fileattr.h>
#include <linux/fsverity.h>
#include <linux/sched/xacct.h>
#include "ctree.h"
#include "disk-io.h"
#include "export.h"
#include "transaction.h"
#include "btrfs_inode.h"
#include "print-tree.h"
#include "volumes.h"
#include "locking.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"
#include "space-info.h"
#include "delalloc-space.h"
#include "block-group.h"
#include "subpage.h"
#include "fs.h"
#include "accessors.h"
#include "extent-tree.h"
#include "root-tree.h"
#include "defrag.h"
#include "dir-item.h"
#include "uuid-tree.h"
#include "ioctl.h"
#include "file.h"
#include "scrub.h"
#include "super.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 */
__u32 version; /* in */
__u8 reserved[28]; /* in */
} __attribute__ ((__packed__));
#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
struct btrfs_ioctl_send_args_32)
struct btrfs_ioctl_encoded_io_args_32 {
compat_uptr_t iov;
compat_ulong_t iovcnt;
__s64 offset;
__u64 flags;
__u64 len;
__u64 unencoded_len;
__u64 unencoded_offset;
__u32 compression;
__u32 encryption;
__u8 reserved[64];
};
#define BTRFS_IOC_ENCODED_READ_32 _IOR(BTRFS_IOCTL_MAGIC, 64, \
struct btrfs_ioctl_encoded_io_args_32)
#define BTRFS_IOC_ENCODED_WRITE_32 _IOW(BTRFS_IOCTL_MAGIC, 64, \
struct btrfs_ioctl_encoded_io_args_32)
#endif
/* 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(struct btrfs_inode *binode)
{
unsigned int iflags = 0;
u32 flags = binode->flags;
u32 ro_flags = binode->ro_flags;
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 (ro_flags & BTRFS_INODE_RO_VERITY)
iflags |= FS_VERITY_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;
if (binode->ro_flags & BTRFS_INODE_RO_VERITY)
new_fl |= S_VERITY;
set_mask_bits(&inode->i_flags,
S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC |
S_VERITY, new_fl);
}
/*
* Check if @flags are a supported and valid set of FS_*_FL flags and that
* the old and new flags are not conflicting
*/
static int check_fsflags(unsigned int old_flags, unsigned int flags)
{
if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
FS_NOATIME_FL | FS_NODUMP_FL | \
FS_SYNC_FL | FS_DIRSYNC_FL | \
FS_NOCOMP_FL | FS_COMPR_FL |
FS_NOCOW_FL))
return -EOPNOTSUPP;
/* COMPR and NOCOMP on new/old are valid */
if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
return -EINVAL;
if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))
return -EINVAL;
/* NOCOW and compression options are mutually exclusive */
if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
return -EINVAL;
if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
return -EINVAL;
return 0;
}
static int check_fsflags_compatible(struct btrfs_fs_info *fs_info,
unsigned int flags)
{
if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL))
return -EPERM;
return 0;
}
/*
* Set flags/xflags from the internal inode flags. The remaining items of
* fsxattr are zeroed.
*/
int btrfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
{
struct btrfs_inode *binode = BTRFS_I(d_inode(dentry));
fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(binode));
return 0;
}
int btrfs_fileattr_set(struct mnt_idmap *idmap,
struct dentry *dentry, struct fileattr *fa)
{
struct inode *inode = d_inode(dentry);
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;
const char *comp = NULL;
u32 binode_flags;
if (btrfs_root_readonly(root))
return -EROFS;
if (fileattr_has_fsx(fa))
return -EOPNOTSUPP;
fsflags = btrfs_mask_fsflags_for_type(inode, fa->flags);
old_fsflags = btrfs_inode_flags_to_fsflags(binode);
ret = check_fsflags(old_fsflags, fsflags);
if (ret)
return ret;
ret = check_fsflags_compatible(fs_info, fsflags);
if (ret)
return ret;
binode_flags = binode->flags;
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 coming from FS_IOC_FSSETXATTR then skip unconverted flags */
if (!fa->flags_valid) {
/* 1 item for the inode */
trans = btrfs_start_transaction(root, 1);
if (IS_ERR(trans))
return PTR_ERR(trans);
goto update_flags;
}
if (fsflags & FS_DIRSYNC_FL)
binode_flags |= BTRFS_INODE_DIRSYNC;
else
binode_flags &= ~BTRFS_INODE_DIRSYNC;
if (fsflags & FS_NOCOW_FL) {
if (S_ISREG(inode->i_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(inode->i_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;
} else if (fsflags & FS_COMPR_FL) {
if (IS_SWAPFILE(inode))
return -ETXTBSY;
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);
} else {
binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
}
/*
* 1 for inode item
* 2 for properties
*/
trans = btrfs_start_transaction(root, 3);
if (IS_ERR(trans))
return PTR_ERR(trans);
if (comp) {
ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
strlen(comp), 0);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto out_end_trans;
}
} else {
ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
0, 0);
if (ret && ret != -ENODATA) {
btrfs_abort_transaction(trans, ret);
goto out_end_trans;
}
}
update_flags:
binode->flags = binode_flags;
btrfs_sync_inode_flags_to_i_flags(inode);
inode_inc_iversion(inode);
inode->i_ctime = current_time(inode);
ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
out_end_trans:
btrfs_end_transaction(trans);
return ret;
}
/*
* Start exclusive operation @type, return true on success
*/
bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,
enum btrfs_exclusive_operation type)
{
bool ret = false;
spin_lock(&fs_info->super_lock);
if (fs_info->exclusive_operation == BTRFS_EXCLOP_NONE) {
fs_info->exclusive_operation = type;
ret = true;
}
spin_unlock(&fs_info->super_lock);
return ret;
}
/*
* Conditionally allow to enter the exclusive operation in case it's compatible
* with the running one. This must be paired with btrfs_exclop_start_unlock and
* btrfs_exclop_finish.
*
* Compatibility:
* - the same type is already running
* - when trying to add a device and balance has been paused
* - not BTRFS_EXCLOP_NONE - this is intentionally incompatible and the caller
* must check the condition first that would allow none -> @type
*/
bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,
enum btrfs_exclusive_operation type)
{
spin_lock(&fs_info->super_lock);
if (fs_info->exclusive_operation == type ||
(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED &&
type == BTRFS_EXCLOP_DEV_ADD))
return true;
spin_unlock(&fs_info->super_lock);
return false;
}
void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info)
{
spin_unlock(&fs_info->super_lock);
}
void btrfs_exclop_finish(struct btrfs_fs_info *fs_info)
{
spin_lock(&fs_info->super_lock);
WRITE_ONCE(fs_info->exclusive_operation, BTRFS_EXCLOP_NONE);
spin_unlock(&fs_info->super_lock);
sysfs_notify(&fs_info->fs_devices->fsid_kobj, NULL, "exclusive_operation");
}
void btrfs_exclop_balance(struct btrfs_fs_info *fs_info,
enum btrfs_exclusive_operation op)
{
switch (op) {
case BTRFS_EXCLOP_BALANCE_PAUSED:
spin_lock(&fs_info->super_lock);
ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE ||
fs_info->exclusive_operation == BTRFS_EXCLOP_DEV_ADD);
fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE_PAUSED;
spin_unlock(&fs_info->super_lock);
break;
case BTRFS_EXCLOP_BALANCE:
spin_lock(&fs_info->super_lock);
ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;
spin_unlock(&fs_info->super_lock);
break;
default:
btrfs_warn(fs_info,
"invalid exclop balance operation %d requested", op);
}
}
static int btrfs_ioctl_getversion(struct inode *inode, int __user *arg)
{
return put_user(inode->i_generation, arg);
}
static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,
void __user *arg)
{
struct btrfs_device *device;
struct fstrim_range range;
u64 minlen = ULLONG_MAX;
u64 num_devices = 0;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
/*
* btrfs_trim_block_group() depends on space cache, which is not
* available in zoned filesystem. So, disallow fitrim on a zoned
* filesystem for now.
*/
if (btrfs_is_zoned(fs_info))
return -EOPNOTSUPP;
/*
* 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 || !bdev_max_discard_sectors(device->bdev))
continue;
num_devices++;
minlen = min_t(u64, bdev_discard_granularity(device->bdev),
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 __pure btrfs_is_empty_uuid(u8 *uuid)
{
int i;
for (i = 0; i < BTRFS_UUID_SIZE; i++) {
if (uuid[i])
return 0;
}
return 1;
}
/*
* Calculate the number of transaction items to reserve for creating a subvolume
* or snapshot, not including the inode, directory entries, or parent directory.
*/
static unsigned int create_subvol_num_items(struct btrfs_qgroup_inherit *inherit)
{
/*
* 1 to add root block
* 1 to add root item
* 1 to add root ref
* 1 to add root backref
* 1 to add UUID item
* 1 to add qgroup info
* 1 to add qgroup limit
*
* Ideally the last two would only be accounted if qgroups are enabled,
* but that can change between now and the time we would insert them.
*/
unsigned int num_items = 7;
if (inherit) {
/* 2 to add qgroup relations for each inherited qgroup */
num_items += 2 * inherit->num_qgroups;
}
return num_items;
}
static noinline int create_subvol(struct mnt_idmap *idmap,
struct inode *dir, struct dentry *dentry,
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 btrfs_new_inode_args new_inode_args = {
.dir = dir,
.dentry = dentry,
.subvol = true,
};
unsigned int trans_num_items;
int ret;
dev_t anon_dev;
u64 objectid;
root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
if (!root_item)
return -ENOMEM;
ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid);
if (ret)
goto out_root_item;
/*
* 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 out_root_item;
}
ret = get_anon_bdev(&anon_dev);
if (ret < 0)
goto out_root_item;
new_inode_args.inode = btrfs_new_subvol_inode(idmap, dir);
if (!new_inode_args.inode) {
ret = -ENOMEM;
goto out_anon_dev;
}
ret = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items);
if (ret)
goto out_inode;
trans_num_items += create_subvol_num_items(inherit);
btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
trans_num_items, false);
if (ret)
goto out_new_inode_args;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
btrfs_subvolume_release_metadata(root, &block_rsv);
goto out_new_inode_args;
}
trans->block_rsv = &block_rsv;
trans->bytes_reserved = block_rsv.size;
ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
if (ret)
goto out;
leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
BTRFS_NESTING_NORMAL);
if (IS_ERR(leaf)) {
ret = PTR_ERR(leaf);
goto out;
}
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));
generate_random_guid(root_item->uuid);
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);
btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID);
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) {
/*
* Since we don't abort the transaction in this case, free the
* tree block so that we don't leak space and leave the
* filesystem in an inconsistent state (an extent item in the
* extent tree with a backreference for a root that does not
* exists).
*/
btrfs_tree_lock(leaf);
btrfs_clean_tree_block(leaf);
btrfs_tree_unlock(leaf);
btrfs_free_tree_block(trans, objectid, leaf, 0, 1);
free_extent_buffer(leaf);
goto out;
}
free_extent_buffer(leaf);
leaf = NULL;
new_root = btrfs_get_new_fs_root(fs_info, objectid, anon_dev);
if (IS_ERR(new_root)) {
ret = PTR_ERR(new_root);
btrfs_abort_transaction(trans, ret);
goto out;
}
/* anon_dev is owned by new_root now. */
anon_dev = 0;
BTRFS_I(new_inode_args.inode)->root = new_root;
/* ... and new_root is owned by new_inode_args.inode now. */
ret = btrfs_record_root_in_trans(trans, new_root);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto out;
}
ret = btrfs_uuid_tree_add(trans, root_item->uuid,
BTRFS_UUID_KEY_SUBVOL, objectid);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto out;
}
ret = btrfs_create_new_inode(trans, &new_inode_args);
if (ret) {
btrfs_abort_transaction(trans, ret);
goto out;
}
d_instantiate_new(dentry, new_inode_args.inode);
new_inode_args.inode = NULL;
out:
trans->block_rsv = NULL;
trans->bytes_reserved = 0;
btrfs_subvolume_release_metadata(root, &block_rsv);
if (ret)
btrfs_end_transaction(trans);
else
ret = btrfs_commit_transaction(trans);
out_new_inode_args:
btrfs_new_inode_args_destroy(&new_inode_args);
out_inode:
iput(new_inode_args.inode);
out_anon_dev:
if (anon_dev)
free_anon_bdev(anon_dev);
out_root_item:
kfree(root_item);
return ret;
}
static int create_snapshot(struct btrfs_root *root, struct inode *dir,
struct dentry *dentry, 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;
unsigned int trans_num_items;
struct btrfs_trans_handle *trans;
int ret;
/* We do not support snapshotting right now. */
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
btrfs_warn(fs_info,
"extent tree v2 doesn't support snapshotting yet");
return -EOPNOTSUPP;
}
if (!test_bit(BTRFS_ROOT_SHAREABLE, &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;
ret = get_anon_bdev(&pending_snapshot->anon_dev);
if (ret < 0)
goto free_pending;
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;
}
btrfs_init_block_rsv(&pending_snapshot->block_rsv,
BTRFS_BLOCK_RSV_TEMP);
/*
* 1 to add dir item
* 1 to add dir index
* 1 to update parent inode item
*/
trans_num_items = create_subvol_num_items(inherit) + 3;
ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
&pending_snapshot->block_rsv,
trans_num_items, false);
if (ret)
goto free_pending;
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;
}
trans->pending_snapshot = pending_snapshot;
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;
pending_snapshot->anon_dev = 0;
fail:
/* Prevent double freeing of anon_dev */
if (ret && pending_snapshot->snap)
pending_snapshot->snap->anon_dev = 0;
btrfs_put_root(pending_snapshot->snap);
btrfs_subvolume_release_metadata(root, &pending_snapshot->block_rsv);
free_pending:
if (pending_snapshot->anon_dev)
free_anon_bdev(pending_snapshot->anon_dev);
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 mnt_idmap *idmap,
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(idmap, dir, MAY_WRITE | MAY_EXEC);
if (error)
return error;
if (IS_APPEND(dir))
return -EPERM;
if (check_sticky(idmap, 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 mnt_idmap *idmap,
struct inode *dir, struct dentry *child)
{
if (d_really_is_positive(child))
return -EEXIST;
if (IS_DEADDIR(dir))
return -ENOENT;
if (!fsuidgid_has_mapping(dir->i_sb, idmap))
return -EOVERFLOW;
return inode_permission(idmap, 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,
struct mnt_idmap *idmap,
const char *name, int namelen,
struct btrfs_root *snap_src,
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;
struct fscrypt_str name_str = FSTR_INIT((char *)name, namelen);
int error;
error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
if (error == -EINTR)
return error;
dentry = lookup_one(idmap, name, parent->dentry, namelen);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto out_unlock;
error = btrfs_may_create(idmap, 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_str);
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, readonly, inherit);
else
error = create_subvol(idmap, dir, dentry, inherit);
if (!error)
fsnotify_mkdir(dir, dentry);
out_up_read:
up_read(&fs_info->subvol_sem);
out_dput:
dput(dentry);
out_unlock:
btrfs_inode_unlock(BTRFS_I(dir), 0);
return error;
}
static noinline int btrfs_mksnapshot(const struct path *parent,
struct mnt_idmap *idmap,
const char *name, int namelen,
struct btrfs_root *root,
bool readonly,
struct btrfs_qgroup_inherit *inherit)
{
int ret;
bool snapshot_force_cow = false;
/*
* 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.
*/
btrfs_drew_read_lock(&root->snapshot_lock);
ret = btrfs_start_delalloc_snapshot(root, false);
if (ret)
goto out;
/*
* 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);
ret = btrfs_mksubvol(parent, idmap, name, namelen,
root, readonly, inherit);
out:
if (snapshot_force_cow)
atomic_dec(&root->snapshot_force_cow);
btrfs_drew_read_unlock(&root->snapshot_lock);
return ret;
}
/*
* Try to start exclusive operation @type or cancel it if it's running.
*
* Return:
* 0 - normal mode, newly claimed op started
* >0 - normal mode, something else is running,
* return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space
* ECANCELED - cancel mode, successful cancel
* ENOTCONN - cancel mode, operation not running anymore
*/
static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info,
enum btrfs_exclusive_operation type, bool cancel)
{
if (!cancel) {
/* Start normal op */
if (!btrfs_exclop_start(fs_info, type))
return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
/* Exclusive operation is now claimed */
return 0;
}
/* Cancel running op */
if (btrfs_exclop_start_try_lock(fs_info, type)) {
/*
* This blocks any exclop finish from setting it to NONE, so we
* request cancellation. Either it runs and we will wait for it,
* or it has finished and no waiting will happen.
*/
atomic_inc(&fs_info->reloc_cancel_req);
btrfs_exclop_start_unlock(fs_info);
if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags))
wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING,
TASK_INTERRUPTIBLE);
return -ECANCELED;
}
/* Something else is running or none */
return -ENOTCONN;
}
static noinline int btrfs_ioctl_resize(struct file *file,
void __user *arg)
{
BTRFS_DEV_LOOKUP_ARGS(args);
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;
bool cancel;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
/*
* Read the arguments before checking exclusivity to be able to
* distinguish regular resize and cancel
*/
vol_args = memdup_user(arg, sizeof(*vol_args));
if (IS_ERR(vol_args)) {
ret = PTR_ERR(vol_args);
goto out_drop;
}
vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
sizestr = vol_args->name;
cancel = (strcmp("cancel", sizestr) == 0);
ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel);
if (ret)
goto out_free;
/* Exclusive operation is now claimed */
devstr = strchr(sizestr, ':');
if (devstr) {
sizestr = devstr + 1;
*devstr = '\0';
devstr = vol_args->name;
ret = kstrtoull(devstr, 10, &devid);
if (ret)
goto out_finish;
if (!devid) {
ret = -EINVAL;
goto out_finish;
}
btrfs_info(fs_info, "resizing devid %llu", devid);
}
args.devid = devid;
device = btrfs_find_device(fs_info->fs_devices, &args);
if (!device) {
btrfs_info(fs_info, "resizer unable to find device %llu",
devid);
ret = -ENODEV;
goto out_finish;
}
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_finish;
}
if (!strcmp(sizestr, "max"))
new_size = bdev_nr_bytes(device->bdev);
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_finish;
}
}
if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
ret = -EPERM;
goto out_finish;
}
old_size = btrfs_device_get_total_bytes(device);
if (mod < 0) {
if (new_size > old_size) {
ret = -EINVAL;
goto out_finish;
}
new_size = old_size - new_size;
} else if (mod > 0) {
if (new_size > ULLONG_MAX - old_size) {
ret = -ERANGE;
goto out_finish;
}
new_size = old_size + new_size;
}
if (new_size < SZ_256M) {
ret = -EINVAL;
goto out_finish;
}
if (new_size > bdev_nr_bytes(device->bdev)) {
ret = -EFBIG;
goto out_finish;
}
new_size = round_down(new_size, fs_info->sectorsize);
if (new_size > old_size) {
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out_finish;
}
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 */
if (ret == 0 && new_size != old_size)
btrfs_info_in_rcu(fs_info,
"resize device %s (devid %llu) from %llu to %llu",
btrfs_dev_name(device), device->devid,
old_size, new_size);
out_finish:
btrfs_exclop_finish(fs_info);
out_free:
kfree(vol_args);
out_drop:
mnt_drop_write_file(file);
return ret;
}
static noinline int __btrfs_ioctl_snap_create(struct file *file,
struct mnt_idmap *idmap,
const char *name, unsigned long fd, int subvol,
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, idmap, name,
namelen, NULL, 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(idmap, src_inode)) {
/*
* Subvolume creation is not restricted, but snapshots
* are limited to own subvolumes only
*/
ret = -EPERM;
} else {
ret = btrfs_mksnapshot(&file->f_path, idmap,
name, namelen,
BTRFS_I(src_inode)->root,
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(file, file_mnt_idmap(file),
vol_args->name, vol_args->fd, subvol,
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;
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_ARGS_MASK) {
ret = -EOPNOTSUPP;
goto free_args;
}
if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
readonly = true;
if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
u64 nums;
if (vol_args->size < sizeof(*inherit) ||
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;
}
if (inherit->num_qgroups > PAGE_SIZE ||
inherit->num_ref_copies > PAGE_SIZE ||
inherit->num_excl_copies > PAGE_SIZE) {
ret = -EINVAL;
goto free_inherit;
}
nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
2 * inherit->num_excl_copies;
if (vol_args->size != struct_size(inherit, qgroups, nums)) {
ret = -EINVAL;
goto free_inherit;
}
}
ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file),
vol_args->name, vol_args->fd, subvol,
readonly, inherit);
if (ret)
goto free_inherit;
free_inherit:
kfree(inherit);
free_args:
kfree(vol_args);
return ret;
}
static noinline int btrfs_ioctl_subvol_getflags(struct inode *inode,
void __user *arg)
{
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(file_mnt_idmap(file), 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_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(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 we fault then loop again so we
* can fault in the pages and -EFAULT there if there's a
* problem. Otherwise we'll fault and then copy the buffer in
* properly this next time through
*/
if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {
ret = 0;
goto out;
}
*sk_offset += sizeof(sh);
if (item_len) {
char __user *up = ubuf + *sk_offset;
/*
* Copy the item, same behavior as above, but reset the
* * sk_offset so we copy the full thing again.
*/
if (read_extent_buffer_to_user_nofault(leaf, up,
item_off, item_len)) {
ret = 0;
*sk_offset -= sizeof(sh);
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_grab_root(BTRFS_I(inode)->root);
} else {
root = btrfs_get_fs_root(info, sk->tree_id, true);
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 = -EFAULT;
/*
* Ensure that the whole user buffer is faulted in at sub-page
* granularity, otherwise the loop may live-lock.
*/
if (fault_in_subpage_writeable(ubuf + sk_offset,
*buf_size - sk_offset))
break;
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_put_root(root);
btrfs_free_path(path);
return ret;
}
static noinline int btrfs_ioctl_tree_search(struct inode *inode,
void __user *argp)
{
struct btrfs_ioctl_search_args __user *uargs = argp;
struct btrfs_ioctl_search_key sk;
int ret;
size_t buf_size;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
return -EFAULT;
buf_size = sizeof(uargs->buf);
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 inode *inode,
void __user *argp)
{
struct btrfs_ioctl_search_args_v2 __user *uarg = argp;
struct btrfs_ioctl_search_args_v2 args;
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 */
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;
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];
root = btrfs_get_fs_root(info, tree_id, true);
if (IS_ERR(root)) {
ret = PTR_ERR(root);
root = NULL;
goto out;
}
key.objectid = dirid;
key.type = BTRFS_INODE_REF_KEY;
key.offset = (u64)-1;
while (1) {
ret = btrfs_search_backwards(root, &key, path);
if (ret < 0)
goto out;
else if (ret > 0) {
ret = -ENOENT;
goto out;
}
l = path->nodes[0];
slot = path->slots[0];
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_put_root(root);
btrfs_free_path(path);
return ret;
}
static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap,
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 = NULL;
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];
root = btrfs_get_fs_root(fs_info, treeid, true);
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_backwards(root, &key, path);
if (ret < 0)
goto out_put;
else if (ret > 0) {
ret = -ENOENT;
goto out_put;
}
leaf = path->nodes[0];
slot = path->slots[0];
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_put;
}
*(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_put;
} else if (ret > 0) {
ret = -ENOENT;
goto out_put;
}
leaf = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(leaf, &key2, slot);
if (key2.objectid != dirid) {
ret = -ENOENT;
goto out_put;
}
temp_inode = btrfs_iget(sb, key2.objectid, root);
if (IS_ERR(temp_inode)) {
ret = PTR_ERR(temp_inode);
goto out_put;
}
ret = inode_permission(idmap, temp_inode,
MAY_READ | MAY_EXEC);
iput(temp_inode);
if (ret) {
ret = -EACCES;
goto out_put;
}
if (key.offset == upper_limit.objectid)
break;
if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
ret = -EACCES;
goto out_put;
}
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_put_root(root);
root = NULL;
btrfs_release_path(path);
}
/* Get the bottom subvolume's name from ROOT_REF */
key.objectid = treeid;
key.type = BTRFS_ROOT_REF_KEY;
key.offset = args->treeid;
ret = btrfs_search_slot(NULL, fs_info->tree_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(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_put:
btrfs_put_root(root);
out:
btrfs_free_path(path);
return ret;
}
static noinline int btrfs_ioctl_ino_lookup(struct btrfs_root *root,
void __user *argp)
{
struct btrfs_ioctl_ino_lookup_args *args;
int ret = 0;
args = memdup_user(argp, sizeof(*args));
if (IS_ERR(args))
return PTR_ERR(args);
/*
* 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 = 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(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(file_mnt_idmap(file), 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 inode *inode, 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;
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;
}
fs_info = BTRFS_I(inode)->root->fs_info;
/* Get root_item of inode's subvolume */
key.objectid = BTRFS_I(inode)->root->root_key.objectid;
root = btrfs_get_fs_root(fs_info, key.objectid, true);
if (IS_ERR(root)) {
ret = PTR_ERR(root);
goto out_free;
}
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 */
key.type = BTRFS_ROOT_BACKREF_KEY;
key.offset = 0;
ret = btrfs_search_slot(NULL, fs_info->tree_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(fs_info->tree_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(leaf, slot)
- sizeof(struct btrfs_root_ref);
read_extent_buffer(leaf, subvol_info->name,
item_off, item_len);
} else {
ret = -ENOENT;
goto out;
}
}
btrfs_free_path(path);
path = NULL;
if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
ret = -EFAULT;
out:
btrfs_put_root(root);
out_free:
btrfs_free_path(path);
kfree(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 btrfs_root *root,
void __user *argp)
{
struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
struct btrfs_root_ref *rref;
struct btrfs_path *path;
struct btrfs_key key;
struct extent_buffer *leaf;
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);
}
objectid = root->root_key.objectid;
key.objectid = objectid;
key.type = BTRFS_ROOT_REF_KEY;
key.offset = rootrefs->min_treeid;
found = 0;
root = root->fs_info->tree_root;
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:
btrfs_free_path(path);
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);
return ret;
}
static noinline int btrfs_ioctl_snap_destroy(struct file *file,
void __user *arg,
bool destroy_v2)
{
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 = NULL;
struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;
struct mnt_idmap *idmap = file_mnt_idmap(file);
char *subvol_name, *subvol_name_ptr = NULL;
int subvol_namelen;
int err = 0;
bool destroy_parent = false;
/* We don't support snapshots with extent tree v2 yet. */
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
btrfs_err(fs_info,
"extent tree v2 doesn't support snapshot deletion yet");
return -EOPNOTSUPP;
}
if (destroy_v2) {
vol_args2 = memdup_user(arg, sizeof(*vol_args2));
if (IS_ERR(vol_args2))
return PTR_ERR(vol_args2);
if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {
err = -EOPNOTSUPP;
goto out;
}
/*
* If SPEC_BY_ID is not set, we are looking for the subvolume by
* name, same as v1 currently does.
*/
if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {
vol_args2->name[BTRFS_SUBVOL_NAME_MAX] = 0;
subvol_name = vol_args2->name;
err = mnt_want_write_file(file);
if (err)
goto out;
} else {
struct inode *old_dir;
if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {
err = -EINVAL;
goto out;
}
err = mnt_want_write_file(file);
if (err)
goto out;
dentry = btrfs_get_dentry(fs_info->sb,
BTRFS_FIRST_FREE_OBJECTID,
vol_args2->subvolid, 0);
if (IS_ERR(dentry)) {
err = PTR_ERR(dentry);
goto out_drop_write;
}
/*
* Change the default parent since the subvolume being
* deleted can be outside of the current mount point.
*/
parent = btrfs_get_parent(dentry);
/*
* At this point dentry->d_name can point to '/' if the
* subvolume we want to destroy is outsite of the
* current mount point, so we need to release the
* current dentry and execute the lookup to return a new
* one with ->d_name pointing to the
* <mount point>/subvol_name.
*/
dput(dentry);
if (IS_ERR(parent)) {
err = PTR_ERR(parent);
goto out_drop_write;
}
old_dir = dir;
dir = d_inode(parent);
/*
* If v2 was used with SPEC_BY_ID, a new parent was
* allocated since the subvolume can be outside of the
* current mount point. Later on we need to release this
* new parent dentry.
*/
destroy_parent = true;
/*
* On idmapped mounts, deletion via subvolid is
* restricted to subvolumes that are immediate
* ancestors of the inode referenced by the file
* descriptor in the ioctl. Otherwise the idmapping
* could potentially be abused to delete subvolumes
* anywhere in the filesystem the user wouldn't be able
* to delete without an idmapped mount.
*/
if (old_dir != dir && idmap != &nop_mnt_idmap) {
err = -EOPNOTSUPP;
goto free_parent;
}
subvol_name_ptr = btrfs_get_subvol_name_from_objectid(
fs_info, vol_args2->subvolid);
if (IS_ERR(subvol_name_ptr)) {
err = PTR_ERR(subvol_name_ptr);
goto free_parent;
}
/* subvol_name_ptr is already nul terminated */
subvol_name = (char *)kbasename(subvol_name_ptr);
}
} else {
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;
subvol_name = vol_args->name;
err = mnt_want_write_file(file);
if (err)
goto out;
}
subvol_namelen = strlen(subvol_name);
if (strchr(subvol_name, '/') ||
strncmp(subvol_name, "..", subvol_namelen) == 0) {
err = -EINVAL;
goto free_subvol_name;
}
if (!S_ISDIR(dir->i_mode)) {
err = -ENOTDIR;
goto free_subvol_name;
}
err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
if (err == -EINTR)
goto free_subvol_name;
dentry = lookup_one(idmap, subvol_name, parent, subvol_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(idmap, inode, MAY_WRITE | MAY_EXEC);
if (err)
goto out_dput;
}
/* check if subvolume may be deleted by a user */
err = btrfs_may_delete(idmap, dir, dentry, 1);
if (err)
goto out_dput;
if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
err = -EINVAL;
goto out_dput;
}
btrfs_inode_lock(BTRFS_I(inode), 0);
err = btrfs_delete_subvolume(BTRFS_I(dir), dentry);
btrfs_inode_unlock(BTRFS_I(inode), 0);
if (!err)
d_delete_notify(dir, dentry);
out_dput:
dput(dentry);
out_unlock_dir:
btrfs_inode_unlock(BTRFS_I(dir), 0);
free_subvol_name:
kfree(subvol_name_ptr);
free_parent:
if (destroy_parent)
dput(parent);
out_drop_write:
mnt_drop_write_file(file);
out:
kfree(vol_args2);
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 = {0};
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(&nop_mnt_idmap, inode, MAY_WRITE)) {
ret = -EPERM;
goto out;
}
if (argp) {
if (copy_from_user(&range, argp, sizeof(range))) {
ret = -EFAULT;
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->f_ra,
&range, BTRFS_OLDEST_GENERATION, 0);
if (ret > 0)
ret = 0;
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;
bool restore_op = false;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
btrfs_err(fs_info, "device add not supported on extent tree v2 yet");
return -EINVAL;
}
if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD)) {
if (!btrfs_exclop_start_try_lock(fs_info, BTRFS_EXCLOP_DEV_ADD))
return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
/*
* We can do the device add because we have a paused balanced,
* change the exclusive op type and remember we should bring
* back the paused balance
*/
fs_info->exclusive_operation = BTRFS_EXCLOP_DEV_ADD;
btrfs_exclop_start_unlock(fs_info);
restore_op = true;
}
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:
if (restore_op)
btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
else
btrfs_exclop_finish(fs_info);
return ret;
}
static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
{
BTRFS_DEV_LOOKUP_ARGS(args);
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;
struct block_device *bdev = NULL;
fmode_t mode;
int ret;
bool cancel = false;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
vol_args = memdup_user(arg, sizeof(*vol_args));
if (IS_ERR(vol_args))
return PTR_ERR(vol_args);
if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {
ret = -EOPNOTSUPP;
goto out;
}
vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
args.devid = vol_args->devid;
} else if (!strcmp("cancel", vol_args->name)) {
cancel = true;
} else {
ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
if (ret)
goto out;
}
ret = mnt_want_write_file(file);
if (ret)
goto out;
ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
cancel);
if (ret)
goto err_drop;
/* Exclusive operation is now claimed */
ret = btrfs_rm_device(fs_info, &args, &bdev, &mode);
btrfs_exclop_finish(fs_info);
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);
}
err_drop:
mnt_drop_write_file(file);
if (bdev)
blkdev_put(bdev, mode);
out:
btrfs_put_dev_args_from_path(&args);
kfree(vol_args);
return ret;
}
static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct inode *inode = file_inode(file);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_ioctl_vol_args *vol_args;
struct block_device *bdev = NULL;
fmode_t mode;
int ret;
bool cancel = false;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
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';
if (!strcmp("cancel", vol_args->name)) {
cancel = true;
} else {
ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
if (ret)
goto out;
}
ret = mnt_want_write_file(file);
if (ret)
goto out;
ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
cancel);
if (ret == 0) {
ret = btrfs_rm_device(fs_info, &args, &bdev, &mode);
if (!ret)
btrfs_info(fs_info, "disk deleted %s", vol_args->name);
btrfs_exclop_finish(fs_info);
}
mnt_drop_write_file(file);
if (bdev)
blkdev_put(bdev, mode);
out:
btrfs_put_dev_args_from_path(&args);
kfree(vol_args);
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;
u64 flags_in;
int ret = 0;
fi_args = memdup_user(arg, sizeof(*fi_args));
if (IS_ERR(fi_args))
return PTR_ERR(fi_args);
flags_in = fi_args->flags;
memset(fi_args, 0, sizeof(*fi_args));
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 (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {
fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);
fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);
fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;
}
if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {
fi_args->generation = fs_info->generation;
fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;
}
if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {
memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,
sizeof(fi_args->metadata_uuid));
fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;
}
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)
{
BTRFS_DEV_LOOKUP_ARGS(args);
struct btrfs_ioctl_dev_info_args *di_args;
struct btrfs_device *dev;
int ret = 0;
di_args = memdup_user(arg, sizeof(*di_args));
if (IS_ERR(di_args))
return PTR_ERR(di_args);
args.devid = di_args->devid;
if (!btrfs_is_empty_uuid(di_args->uuid))
args.uuid = di_args->uuid;
rcu_read_lock();
dev = btrfs_find_device(fs_info->fs_devices, &args);
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)
strscpy(di_args->path, btrfs_dev_name(dev), sizeof(di_args->path));
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 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 = NULL;
struct btrfs_disk_key disk_key;
struct fscrypt_str name = FSTR_INIT("default", 7);
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;
new_root = btrfs_get_fs_root(fs_info, objectid, true);
if (IS_ERR(new_root)) {
ret = PTR_ERR(new_root);
goto out;
}
if (!is_fstree(new_root->root_key.objectid)) {
ret = -ENOENT;
goto out_free;
}
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto out_free;
}
trans = btrfs_start_transaction(root, 1);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out_free;
}
dir_id = btrfs_super_root_dir(fs_info->super_copy);
di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
dir_id, &name, 1);
if (IS_ERR_OR_NULL(di)) {
btrfs_release_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_free;
}
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_release_path(path);
btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
btrfs_end_transaction(trans);
out_free:
btrfs_put_root(new_root);
btrfs_free_path(path);
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 *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->length;
space->used_bytes += block_group->used;
}
}
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;
list_for_each_entry(tmp, &fs_info->space_info, list) {
if (tmp->flags == types[i]) {
info = tmp;
break;
}
}
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;
list_for_each_entry(tmp, &fs_info->space_info, list) {
if (tmp->flags == types[i]) {
info = tmp;
break;
}
}
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;
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;
btrfs_commit_transaction_async(trans);
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;
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
btrfs_err(fs_info, "scrub is not supported on extent tree v2 yet");
return -EINVAL;
}
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);
/*
* Copy scrub args to user space even if btrfs_scrub_dev() returned an
* error. This is important as it allows user space to know how much
* progress scrub has done. For example, if scrub is canceled we get
* -ECANCELED from btrfs_scrub_dev() and return that error back to user
* space. Later user space can inspect the progress from the structure
* btrfs_ioctl_scrub_args and resume scrub from where it left off
* previously (btrfs-progs does this).
* If we fail to copy the btrfs_ioctl_scrub_args structure to user space
* then return -EFAULT to signal the structure was not copied or it may
* be corrupt and unreliable due to a partial copy.
*/
if (copy_to_user(arg, sa, sizeof(*sa)))
ret = -EFAULT;
if (!(sa->flags & BTRFS_SCRUB_READONLY))
mnt_drop_write_file(file);
out:
kfree(sa);
return ret;
}
static long btrfs_ioctl_scrub_cancel(struct btrfs_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;
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
btrfs_err(fs_info, "device replace not supported on extent tree v2 yet");
return -EINVAL;
}
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 (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) {
ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
} else {
ret = btrfs_dev_replace_by_ioctl(fs_info, p);
btrfs_exclop_finish(fs_info);
}
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;
}
btrfs_free_path(path);
path = NULL;
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 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);
}
inodes = init_data_container(size);
if (IS_ERR(inodes)) {
ret = PTR_ERR(inodes);
goto out_loi;
}
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto out;
}
ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
inodes, ignore_offset);
btrfs_free_path(path);
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:
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);
}
/*
* Try to acquire fs_info::balance_mutex as well as set BTRFS_EXLCOP_BALANCE as
* required.
*
* @fs_info: the filesystem
* @excl_acquired: ptr to boolean value which is set to false in case balance
* is being resumed
*
* Return 0 on success in which case both fs_info::balance is acquired as well
* as exclusive ops are blocked. In case of failure return an error code.
*/
static int btrfs_try_lock_balance(struct btrfs_fs_info *fs_info, bool *excl_acquired)
{
int ret;
/*
* Exclusive operation is locked. Three possibilities:
* (1) some other op is running
* (2) balance is running
* (3) balance is paused -- special case (think resume)
*/
while (1) {
if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
*excl_acquired = true;
mutex_lock(&fs_info->balance_mutex);
return 0;
}
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)) {
/* This is (2) */
ret = -EINPROGRESS;
goto out_failure;
} else {
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) */
*excl_acquired = false;
return 0;
}
}
} else {
/* This is (1) */
ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
goto out_failure;
}
mutex_unlock(&fs_info->balance_mutex);
}
out_failure:
mutex_unlock(&fs_info->balance_mutex);
*excl_acquired = false;
return ret;
}
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 = true;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = mnt_want_write_file(file);
if (ret)
return ret;
bargs = memdup_user(arg, sizeof(*bargs));
if (IS_ERR(bargs)) {
ret = PTR_ERR(bargs);
bargs = NULL;
goto out;
}
ret = btrfs_try_lock_balance(fs_info, &need_unlock);
if (ret)
goto out;
lockdep_assert_held(&fs_info->balance_mutex);
if (bargs->flags & BTRFS_BALANCE_RESUME) {
if (!fs_info->balance_ctl) {
ret = -ENOTCONN;
goto out_unlock;
}
bctl = fs_info->balance_ctl;
spin_lock(&fs_info->balance_lock);
bctl->flags |= BTRFS_BALANCE_RESUME;
spin_unlock(&fs_info->balance_lock);
btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE);
goto do_balance;
}
if (bargs->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
ret = -EINVAL;
goto out_unlock;
}
if (fs_info->balance_ctl) {
ret = -EINPROGRESS;
goto out_unlock;
}
bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
if (!bctl) {
ret = -ENOMEM;
goto out_unlock;
}
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;
do_balance:
/*
* Ownership of bctl and exclusive operation 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) {
if (copy_to_user(arg, bargs, sizeof(*bargs)))
ret = -EFAULT;
}
kfree(bctl);
out_unlock:
mutex_unlock(&fs_info->balance_mutex);
if (need_unlock)
btrfs_exclop_finish(fs_info);
out:
mnt_drop_write_file(file);
kfree(bargs);
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 btrfs_fs_info *fs_info,
void __user *arg)
{
struct btrfs_ioctl_quota_rescan_args qsa = {0};
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
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)))
return -EFAULT;
return 0;
}
static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,
void __user *arg)
{
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 mnt_idmap *idmap,
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(idmap, 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, file_mnt_idmap(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, file_mnt_idmap(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 btrfs_fs_info *fs_info,
void __user *arg)
{
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 btrfs_fs_info *fs_info,
void __user *arg)
{
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_name(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 inode *inode, 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(inode, arg);
kfree(arg);
return ret;
}
static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp,
bool compat)
{
struct btrfs_ioctl_encoded_io_args args = { 0 };
size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args,
flags);
size_t copy_end;
struct iovec iovstack[UIO_FASTIOV];
struct iovec *iov = iovstack;
struct iov_iter iter;
loff_t pos;
struct kiocb kiocb;
ssize_t ret;
if (!capable(CAP_SYS_ADMIN)) {
ret = -EPERM;
goto out_acct;
}
if (compat) {
#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
struct btrfs_ioctl_encoded_io_args_32 args32;
copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32,
flags);
if (copy_from_user(&args32, argp, copy_end)) {
ret = -EFAULT;
goto out_acct;
}
args.iov = compat_ptr(args32.iov);
args.iovcnt = args32.iovcnt;
args.offset = args32.offset;
args.flags = args32.flags;
#else
return -ENOTTY;
#endif
} else {
copy_end = copy_end_kernel;
if (copy_from_user(&args, argp, copy_end)) {
ret = -EFAULT;
goto out_acct;
}
}
if (args.flags != 0) {
ret = -EINVAL;
goto out_acct;
}
ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
&iov, &iter);
if (ret < 0)
goto out_acct;
if (iov_iter_count(&iter) == 0) {
ret = 0;
goto out_iov;
}
pos = args.offset;
ret = rw_verify_area(READ, file, &pos, args.len);
if (ret < 0)
goto out_iov;
init_sync_kiocb(&kiocb, file);
kiocb.ki_pos = pos;
ret = btrfs_encoded_read(&kiocb, &iter, &args);
if (ret >= 0) {
fsnotify_access(file);
if (copy_to_user(argp + copy_end,
(char *)&args + copy_end_kernel,
sizeof(args) - copy_end_kernel))
ret = -EFAULT;
}
out_iov:
kfree(iov);
out_acct:
if (ret > 0)
add_rchar(current, ret);
inc_syscr(current);
return ret;
}
static int btrfs_ioctl_encoded_write(struct file *file, void __user *argp, bool compat)
{
struct btrfs_ioctl_encoded_io_args args;
struct iovec iovstack[UIO_FASTIOV];
struct iovec *iov = iovstack;
struct iov_iter iter;
loff_t pos;
struct kiocb kiocb;
ssize_t ret;
if (!capable(CAP_SYS_ADMIN)) {
ret = -EPERM;
goto out_acct;
}
if (!(file->f_mode & FMODE_WRITE)) {
ret = -EBADF;
goto out_acct;
}
if (compat) {
#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
struct btrfs_ioctl_encoded_io_args_32 args32;
if (copy_from_user(&args32, argp, sizeof(args32))) {
ret = -EFAULT;
goto out_acct;
}
args.iov = compat_ptr(args32.iov);
args.iovcnt = args32.iovcnt;
args.offset = args32.offset;
args.flags = args32.flags;
args.len = args32.len;
args.unencoded_len = args32.unencoded_len;
args.unencoded_offset = args32.unencoded_offset;
args.compression = args32.compression;
args.encryption = args32.encryption;
memcpy(args.reserved, args32.reserved, sizeof(args.reserved));
#else
return -ENOTTY;
#endif
} else {
if (copy_from_user(&args, argp, sizeof(args))) {
ret = -EFAULT;
goto out_acct;
}
}
ret = -EINVAL;
if (args.flags != 0)
goto out_acct;
if (memchr_inv(args.reserved, 0, sizeof(args.reserved)))
goto out_acct;
if (args.compression == BTRFS_ENCODED_IO_COMPRESSION_NONE &&
args.encryption == BTRFS_ENCODED_IO_ENCRYPTION_NONE)
goto out_acct;
if (args.compression >= BTRFS_ENCODED_IO_COMPRESSION_TYPES ||
args.encryption >= BTRFS_ENCODED_IO_ENCRYPTION_TYPES)
goto out_acct;
if (args.unencoded_offset > args.unencoded_len)
goto out_acct;
if (args.len > args.unencoded_len - args.unencoded_offset)
goto out_acct;
ret = import_iovec(ITER_SOURCE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
&iov, &iter);
if (ret < 0)
goto out_acct;
file_start_write(file);
if (iov_iter_count(&iter) == 0) {
ret = 0;
goto out_end_write;
}
pos = args.offset;
ret = rw_verify_area(WRITE, file, &pos, args.len);
if (ret < 0)
goto out_end_write;
init_sync_kiocb(&kiocb, file);
ret = kiocb_set_rw_flags(&kiocb, 0);
if (ret)
goto out_end_write;
kiocb.ki_pos = pos;
ret = btrfs_do_write_iter(&kiocb, &iter, &args);
if (ret > 0)
fsnotify_modify(file);
out_end_write:
file_end_write(file);
kfree(iov);
out_acct:
if (ret > 0)
add_wchar(current, ret);
inc_syscw(current);
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_GETVERSION:
return btrfs_ioctl_getversion(inode, argp);
case FS_IOC_GETFSLABEL:
return btrfs_ioctl_get_fslabel(fs_info, argp);
case FS_IOC_SETFSLABEL:
return btrfs_ioctl_set_fslabel(file, argp);
case FITRIM:
return btrfs_ioctl_fitrim(fs_info, 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, false);
case BTRFS_IOC_SNAP_DESTROY_V2:
return btrfs_ioctl_snap_destroy(file, argp, true);
case BTRFS_IOC_SUBVOL_GETFLAGS:
return btrfs_ioctl_subvol_getflags(inode, 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_TREE_SEARCH:
return btrfs_ioctl_tree_search(inode, argp);
case BTRFS_IOC_TREE_SEARCH_V2:
return btrfs_ioctl_tree_search_v2(inode, argp);
case BTRFS_IOC_INO_LOOKUP:
return btrfs_ioctl_ino_lookup(root, 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, LONG_MAX, false);
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(inode, argp, false);
#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
case BTRFS_IOC_SEND_32:
return _btrfs_ioctl_send(inode, 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(fs_info, argp);
case BTRFS_IOC_QUOTA_RESCAN_WAIT:
return btrfs_ioctl_quota_rescan_wait(fs_info, argp);
case BTRFS_IOC_DEV_REPLACE:
return btrfs_ioctl_dev_replace(fs_info, argp);
case BTRFS_IOC_GET_SUPPORTED_FEATURES:
return btrfs_ioctl_get_supported_features(argp);
case BTRFS_IOC_GET_FEATURES:
return btrfs_ioctl_get_features(fs_info, argp);
case BTRFS_IOC_SET_FEATURES:
return btrfs_ioctl_set_features(file, argp);
case BTRFS_IOC_GET_SUBVOL_INFO:
return btrfs_ioctl_get_subvol_info(inode, argp);
case BTRFS_IOC_GET_SUBVOL_ROOTREF:
return btrfs_ioctl_get_subvol_rootref(root, argp);
case BTRFS_IOC_INO_LOOKUP_USER:
return btrfs_ioctl_ino_lookup_user(file, argp);
case FS_IOC_ENABLE_VERITY:
return fsverity_ioctl_enable(file, (const void __user *)argp);
case FS_IOC_MEASURE_VERITY:
return fsverity_ioctl_measure(file, argp);
case BTRFS_IOC_ENCODED_READ:
return btrfs_ioctl_encoded_read(file, argp, false);
case BTRFS_IOC_ENCODED_WRITE:
return btrfs_ioctl_encoded_write(file, argp, false);
#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
case BTRFS_IOC_ENCODED_READ_32:
return btrfs_ioctl_encoded_read(file, argp, true);
case BTRFS_IOC_ENCODED_WRITE_32:
return btrfs_ioctl_encoded_write(file, argp, true);
#endif
}
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_GETVERSION:
cmd = FS_IOC_GETVERSION;
break;
}
return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
}
#endif
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