ioctl.c 129.2 KB
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Christoph Hellwig 已提交
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/*
 * Copyright (C) 2007 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#include <linux/kernel.h>
#include <linux/bio.h>
#include <linux/buffer_head.h>
#include <linux/file.h>
#include <linux/fs.h>
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#include <linux/fsnotify.h>
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#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/time.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/backing-dev.h>
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#include <linux/mount.h>
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#include <linux/mpage.h>
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#include <linux/namei.h>
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#include <linux/swap.h>
#include <linux/writeback.h>
#include <linux/statfs.h>
#include <linux/compat.h>
#include <linux/bit_spinlock.h>
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#include <linux/security.h>
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#include <linux/xattr.h>
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#include <linux/vmalloc.h>
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#include <linux/slab.h>
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#include <linux/blkdev.h>
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#include <linux/uuid.h>
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#include <linux/btrfs.h>
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#include <linux/uaccess.h>
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#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "btrfs_inode.h"
#include "print-tree.h"
#include "volumes.h"
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#include "locking.h"
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#include "inode-map.h"
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#include "backref.h"
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#include "rcu-string.h"
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#include "send.h"
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#include "dev-replace.h"
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#include "props.h"
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#include "sysfs.h"
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#include "qgroup.h"
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#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


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static int btrfs_clone(struct inode *src, struct inode *inode,
		       u64 off, u64 olen, u64 olen_aligned, u64 destoff);

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/* Mask out flags that are inappropriate for the given type of inode. */
static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
{
	if (S_ISDIR(mode))
		return flags;
	else if (S_ISREG(mode))
		return flags & ~FS_DIRSYNC_FL;
	else
		return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
}

/*
 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
 */
static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
{
	unsigned int iflags = 0;

	if (flags & BTRFS_INODE_SYNC)
		iflags |= FS_SYNC_FL;
	if (flags & BTRFS_INODE_IMMUTABLE)
		iflags |= FS_IMMUTABLE_FL;
	if (flags & BTRFS_INODE_APPEND)
		iflags |= FS_APPEND_FL;
	if (flags & BTRFS_INODE_NODUMP)
		iflags |= FS_NODUMP_FL;
	if (flags & BTRFS_INODE_NOATIME)
		iflags |= FS_NOATIME_FL;
	if (flags & BTRFS_INODE_DIRSYNC)
		iflags |= FS_DIRSYNC_FL;
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	if (flags & BTRFS_INODE_NODATACOW)
		iflags |= FS_NOCOW_FL;

	if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
		iflags |= FS_COMPR_FL;
	else if (flags & BTRFS_INODE_NOCOMPRESS)
		iflags |= FS_NOCOMP_FL;
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	return iflags;
}

/*
 * Update inode->i_flags based on the btrfs internal flags.
 */
void btrfs_update_iflags(struct inode *inode)
{
	struct btrfs_inode *ip = BTRFS_I(inode);
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	unsigned int new_fl = 0;
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	if (ip->flags & BTRFS_INODE_SYNC)
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		new_fl |= S_SYNC;
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	if (ip->flags & BTRFS_INODE_IMMUTABLE)
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		new_fl |= S_IMMUTABLE;
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	if (ip->flags & BTRFS_INODE_APPEND)
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		new_fl |= S_APPEND;
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	if (ip->flags & BTRFS_INODE_NOATIME)
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		new_fl |= S_NOATIME;
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	if (ip->flags & BTRFS_INODE_DIRSYNC)
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		new_fl |= S_DIRSYNC;

	set_mask_bits(&inode->i_flags,
		      S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
		      new_fl);
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}

/*
 * Inherit flags from the parent inode.
 *
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 * Currently only the compression flags and the cow flags are inherited.
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 */
void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
{
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	unsigned int flags;

	if (!dir)
		return;

	flags = BTRFS_I(dir)->flags;
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	if (flags & BTRFS_INODE_NOCOMPRESS) {
		BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
		BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
	} else if (flags & BTRFS_INODE_COMPRESS) {
		BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
		BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
	}

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	if (flags & BTRFS_INODE_NODATACOW) {
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		BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
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		if (S_ISREG(inode->i_mode))
			BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
	}
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	btrfs_update_iflags(inode);
}

static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
{
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	struct btrfs_inode *ip = BTRFS_I(file_inode(file));
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	unsigned int flags = btrfs_flags_to_ioctl(ip->flags);

	if (copy_to_user(arg, &flags, sizeof(flags)))
		return -EFAULT;
	return 0;
}

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static int check_flags(unsigned int flags)
{
	if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
		      FS_NOATIME_FL | FS_NODUMP_FL | \
		      FS_SYNC_FL | FS_DIRSYNC_FL | \
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		      FS_NOCOMP_FL | FS_COMPR_FL |
		      FS_NOCOW_FL))
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		return -EOPNOTSUPP;

	if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
		return -EINVAL;

	return 0;
}

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static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
{
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	struct inode *inode = file_inode(file);
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	struct btrfs_inode *ip = BTRFS_I(inode);
	struct btrfs_root *root = ip->root;
	struct btrfs_trans_handle *trans;
	unsigned int flags, oldflags;
	int ret;
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	u64 ip_oldflags;
	unsigned int i_oldflags;
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	umode_t mode;
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	if (!inode_owner_or_capable(inode))
		return -EPERM;

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	if (btrfs_root_readonly(root))
		return -EROFS;

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	if (copy_from_user(&flags, arg, sizeof(flags)))
		return -EFAULT;

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	ret = check_flags(flags);
	if (ret)
		return ret;
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	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

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	mutex_lock(&inode->i_mutex);

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	ip_oldflags = ip->flags;
	i_oldflags = inode->i_flags;
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	mode = inode->i_mode;
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	flags = btrfs_mask_flags(inode->i_mode, flags);
	oldflags = btrfs_flags_to_ioctl(ip->flags);
	if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
		if (!capable(CAP_LINUX_IMMUTABLE)) {
			ret = -EPERM;
			goto out_unlock;
		}
	}

	if (flags & FS_SYNC_FL)
		ip->flags |= BTRFS_INODE_SYNC;
	else
		ip->flags &= ~BTRFS_INODE_SYNC;
	if (flags & FS_IMMUTABLE_FL)
		ip->flags |= BTRFS_INODE_IMMUTABLE;
	else
		ip->flags &= ~BTRFS_INODE_IMMUTABLE;
	if (flags & FS_APPEND_FL)
		ip->flags |= BTRFS_INODE_APPEND;
	else
		ip->flags &= ~BTRFS_INODE_APPEND;
	if (flags & FS_NODUMP_FL)
		ip->flags |= BTRFS_INODE_NODUMP;
	else
		ip->flags &= ~BTRFS_INODE_NODUMP;
	if (flags & FS_NOATIME_FL)
		ip->flags |= BTRFS_INODE_NOATIME;
	else
		ip->flags &= ~BTRFS_INODE_NOATIME;
	if (flags & FS_DIRSYNC_FL)
		ip->flags |= BTRFS_INODE_DIRSYNC;
	else
		ip->flags &= ~BTRFS_INODE_DIRSYNC;
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	if (flags & FS_NOCOW_FL) {
		if (S_ISREG(mode)) {
			/*
			 * It's safe to turn csums off here, no extents exist.
			 * Otherwise we want the flag to reflect the real COW
			 * status of the file and will not set it.
			 */
			if (inode->i_size == 0)
				ip->flags |= BTRFS_INODE_NODATACOW
					   | BTRFS_INODE_NODATASUM;
		} else {
			ip->flags |= BTRFS_INODE_NODATACOW;
		}
	} else {
		/*
		 * Revert back under same assuptions as above
		 */
		if (S_ISREG(mode)) {
			if (inode->i_size == 0)
				ip->flags &= ~(BTRFS_INODE_NODATACOW
				             | BTRFS_INODE_NODATASUM);
		} else {
			ip->flags &= ~BTRFS_INODE_NODATACOW;
		}
	}
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	/*
	 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
	 * flag may be changed automatically if compression code won't make
	 * things smaller.
	 */
	if (flags & FS_NOCOMP_FL) {
		ip->flags &= ~BTRFS_INODE_COMPRESS;
		ip->flags |= BTRFS_INODE_NOCOMPRESS;
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		ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
		if (ret && ret != -ENODATA)
			goto out_drop;
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	} else if (flags & FS_COMPR_FL) {
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		const char *comp;

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		ip->flags |= BTRFS_INODE_COMPRESS;
		ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
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		if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
			comp = "lzo";
		else
			comp = "zlib";
		ret = btrfs_set_prop(inode, "btrfs.compression",
				     comp, strlen(comp), 0);
		if (ret)
			goto out_drop;

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	} else {
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		ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
		if (ret && ret != -ENODATA)
			goto out_drop;
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		ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
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	}
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	trans = btrfs_start_transaction(root, 1);
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	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out_drop;
	}
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	btrfs_update_iflags(inode);
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	inode_inc_iversion(inode);
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	inode->i_ctime = CURRENT_TIME;
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	ret = btrfs_update_inode(trans, root, inode);

	btrfs_end_transaction(trans, root);
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 out_drop:
	if (ret) {
		ip->flags = ip_oldflags;
		inode->i_flags = i_oldflags;
	}
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 out_unlock:
	mutex_unlock(&inode->i_mutex);
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	mnt_drop_write_file(file);
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	return ret;
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}

static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
{
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	struct inode *inode = file_inode(file);
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	return put_user(inode->i_generation, arg);
}
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static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
{
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	struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
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	struct btrfs_device *device;
	struct request_queue *q;
	struct fstrim_range range;
	u64 minlen = ULLONG_MAX;
	u64 num_devices = 0;
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	u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
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	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

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	rcu_read_lock();
	list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
				dev_list) {
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		if (!device->bdev)
			continue;
		q = bdev_get_queue(device->bdev);
		if (blk_queue_discard(q)) {
			num_devices++;
			minlen = min((u64)q->limits.discard_granularity,
				     minlen);
		}
	}
398
	rcu_read_unlock();
399

400 401 402 403
	if (!num_devices)
		return -EOPNOTSUPP;
	if (copy_from_user(&range, arg, sizeof(range)))
		return -EFAULT;
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	if (range.start > total_bytes ||
	    range.len < fs_info->sb->s_blocksize)
406
		return -EINVAL;
407

408
	range.len = min(range.len, total_bytes - range.start);
409
	range.minlen = max(range.minlen, minlen);
410
	ret = btrfs_trim_fs(fs_info->tree_root, &range);
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	if (ret < 0)
		return ret;

	if (copy_to_user(arg, &range, sizeof(range)))
		return -EFAULT;

	return 0;
}

420 421
int btrfs_is_empty_uuid(u8 *uuid)
{
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	int i;

	for (i = 0; i < BTRFS_UUID_SIZE; i++) {
		if (uuid[i])
			return 0;
	}
	return 1;
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}

431
static noinline int create_subvol(struct inode *dir,
432
				  struct dentry *dentry,
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				  char *name, int namelen,
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				  u64 *async_transid,
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				  struct btrfs_qgroup_inherit *inherit)
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{
	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;
442
	struct btrfs_root *root = BTRFS_I(dir)->root;
443
	struct btrfs_root *new_root;
444
	struct btrfs_block_rsv block_rsv;
445
	struct timespec cur_time = CURRENT_TIME;
446
	struct inode *inode;
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	int ret;
	int err;
	u64 objectid;
	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
451
	u64 index = 0;
452
	u64 qgroup_reserved;
453
	uuid_le new_uuid;
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455
	ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
456
	if (ret)
457
		return ret;
458

459
	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
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	/*
461 462
	 * The same as the snapshot creation, please see the comment
	 * of create_snapshot().
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	 */
464
	ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
465
					       8, &qgroup_reserved, false);
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	if (ret)
		return ret;

	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
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		btrfs_subvolume_release_metadata(root, &block_rsv,
						 qgroup_reserved);
		return ret;
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	}
	trans->block_rsv = &block_rsv;
	trans->bytes_reserved = block_rsv.size;
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479
	ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
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	if (ret)
		goto fail;

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	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
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	if (IS_ERR(leaf)) {
		ret = PTR_ERR(leaf);
		goto fail;
	}
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489
	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
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	btrfs_set_header_bytenr(leaf, leaf->start);
	btrfs_set_header_generation(leaf, trans->transid);
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	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
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	btrfs_set_header_owner(leaf, objectid);

495
	write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
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			    BTRFS_FSID_SIZE);
497
	write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
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			    btrfs_header_chunk_tree_uuid(leaf),
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			    BTRFS_UUID_SIZE);
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	btrfs_mark_buffer_dirty(leaf);

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	memset(&root_item, 0, sizeof(root_item));

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	inode_item = &root_item.inode;
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	btrfs_set_stack_inode_generation(inode_item, 1);
	btrfs_set_stack_inode_size(inode_item, 3);
	btrfs_set_stack_inode_nlink(inode_item, 1);
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	btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
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	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
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	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);
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	btrfs_set_root_bytenr(&root_item, leaf->start);
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	btrfs_set_root_generation(&root_item, trans->transid);
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	btrfs_set_root_level(&root_item, 0);
	btrfs_set_root_refs(&root_item, 1);
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	btrfs_set_root_used(&root_item, leaf->len);
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	btrfs_set_root_last_snapshot(&root_item, 0);
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	btrfs_set_root_generation_v2(&root_item,
			btrfs_root_generation(&root_item));
	uuid_le_gen(&new_uuid);
	memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
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	btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
	btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
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	root_item.ctime = root_item.otime;
	btrfs_set_root_ctransid(&root_item, trans->transid);
	btrfs_set_root_otransid(&root_item, trans->transid);
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532
	btrfs_tree_unlock(leaf);
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	free_extent_buffer(leaf);
	leaf = NULL;

	btrfs_set_root_dirid(&root_item, new_dirid);

	key.objectid = objectid;
539
	key.offset = 0;
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	key.type = BTRFS_ROOT_ITEM_KEY;
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	ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
				&root_item);
	if (ret)
		goto fail;

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	key.offset = (u64)-1;
	new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
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	if (IS_ERR(new_root)) {
		btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
		ret = PTR_ERR(new_root);
		goto fail;
	}
553 554 555

	btrfs_record_root_in_trans(trans, new_root);

556
	ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
557 558
	if (ret) {
		/* We potentially lose an unused inode item here */
559
		btrfs_abort_transaction(trans, root, ret);
560 561 562
		goto fail;
	}

C
Christoph Hellwig 已提交
563 564 565
	/*
	 * insert the directory item
	 */
566
	ret = btrfs_set_inode_index(dir, &index);
567 568 569 570
	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
		goto fail;
	}
571 572

	ret = btrfs_insert_dir_item(trans, root,
573
				    name, namelen, dir, &key,
574
				    BTRFS_FT_DIR, index);
575 576
	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
C
Christoph Hellwig 已提交
577
		goto fail;
578
	}
579

580 581 582 583
	btrfs_i_size_write(dir, dir->i_size + namelen * 2);
	ret = btrfs_update_inode(trans, root, dir);
	BUG_ON(ret);

584
	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
585
				 objectid, root->root_key.objectid,
L
Li Zefan 已提交
586
				 btrfs_ino(dir), index, name, namelen);
587
	BUG_ON(ret);
C
Christoph Hellwig 已提交
588

589 590 591 592 593 594
	ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
				  root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
				  objectid);
	if (ret)
		btrfs_abort_transaction(trans, root, ret);

C
Christoph Hellwig 已提交
595
fail:
596 597
	trans->block_rsv = NULL;
	trans->bytes_reserved = 0;
598 599
	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);

S
Sage Weil 已提交
600 601 602
	if (async_transid) {
		*async_transid = trans->transid;
		err = btrfs_commit_transaction_async(trans, root, 1);
603 604
		if (err)
			err = btrfs_commit_transaction(trans, root);
S
Sage Weil 已提交
605 606 607
	} else {
		err = btrfs_commit_transaction(trans, root);
	}
C
Christoph Hellwig 已提交
608 609
	if (err && !ret)
		ret = err;
610

611 612
	if (!ret) {
		inode = btrfs_lookup_dentry(dir, dentry);
613 614
		if (IS_ERR(inode))
			return PTR_ERR(inode);
615 616
		d_instantiate(dentry, inode);
	}
C
Christoph Hellwig 已提交
617 618 619
	return ret;
}

620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636
static void btrfs_wait_nocow_write(struct btrfs_root *root)
{
	s64 writers;
	DEFINE_WAIT(wait);

	do {
		prepare_to_wait(&root->subv_writers->wait, &wait,
				TASK_UNINTERRUPTIBLE);

		writers = percpu_counter_sum(&root->subv_writers->counter);
		if (writers)
			schedule();

		finish_wait(&root->subv_writers->wait, &wait);
	} while (writers);
}

637 638 639 640
static int create_snapshot(struct btrfs_root *root, struct inode *dir,
			   struct dentry *dentry, char *name, int namelen,
			   u64 *async_transid, bool readonly,
			   struct btrfs_qgroup_inherit *inherit)
C
Christoph Hellwig 已提交
641
{
642
	struct inode *inode;
C
Christoph Hellwig 已提交
643 644
	struct btrfs_pending_snapshot *pending_snapshot;
	struct btrfs_trans_handle *trans;
645
	int ret;
C
Christoph Hellwig 已提交
646

647
	if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
C
Christoph Hellwig 已提交
648 649
		return -EINVAL;

650
	atomic_inc(&root->will_be_snapshoted);
651
	smp_mb__after_atomic();
652 653
	btrfs_wait_nocow_write(root);

654 655
	ret = btrfs_start_delalloc_inodes(root, 0);
	if (ret)
656
		goto out;
657

658
	btrfs_wait_ordered_extents(root, -1);
659

660
	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
661 662 663 664
	if (!pending_snapshot) {
		ret = -ENOMEM;
		goto out;
	}
665

666 667
	btrfs_init_block_rsv(&pending_snapshot->block_rsv,
			     BTRFS_BLOCK_RSV_TEMP);
668 669 670 671 672 673
	/*
	 * 1 - parent dir inode
	 * 2 - dir entries
	 * 1 - root item
	 * 2 - root ref/backref
	 * 1 - root of snapshot
674
	 * 1 - UUID item
675 676
	 */
	ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
677
					&pending_snapshot->block_rsv, 8,
678 679
					&pending_snapshot->qgroup_reserved,
					false);
680
	if (ret)
681
		goto free;
682

683
	pending_snapshot->dentry = dentry;
C
Christoph Hellwig 已提交
684
	pending_snapshot->root = root;
L
Li Zefan 已提交
685
	pending_snapshot->readonly = readonly;
686
	pending_snapshot->dir = dir;
687
	pending_snapshot->inherit = inherit;
688

689
	trans = btrfs_start_transaction(root, 0);
690 691 692 693 694
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto fail;
	}

695
	spin_lock(&root->fs_info->trans_lock);
C
Christoph Hellwig 已提交
696 697
	list_add(&pending_snapshot->list,
		 &trans->transaction->pending_snapshots);
698
	spin_unlock(&root->fs_info->trans_lock);
S
Sage Weil 已提交
699 700 701 702
	if (async_transid) {
		*async_transid = trans->transid;
		ret = btrfs_commit_transaction_async(trans,
				     root->fs_info->extent_root, 1);
703 704
		if (ret)
			ret = btrfs_commit_transaction(trans, root);
S
Sage Weil 已提交
705 706 707 708
	} else {
		ret = btrfs_commit_transaction(trans,
					       root->fs_info->extent_root);
	}
709
	if (ret)
710
		goto fail;
711 712 713 714 715

	ret = pending_snapshot->error;
	if (ret)
		goto fail;

716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748
	ret = btrfs_orphan_cleanup(pending_snapshot->snap);
	if (ret)
		goto fail;

	/*
	 * If orphan cleanup did remove any orphans, it means the tree was
	 * modified and therefore the commit root is not the same as the
	 * current root anymore. This is a problem, because send uses the
	 * commit root and therefore can see inode items that don't exist
	 * in the current root anymore, and for example make calls to
	 * btrfs_iget, which will do tree lookups based on the current root
	 * and not on the commit root. Those lookups will fail, returning a
	 * -ESTALE error, and making send fail with that error. So make sure
	 * a send does not see any orphans we have just removed, and that it
	 * will see the same inodes regardless of whether a transaction
	 * commit happened before it started (meaning that the commit root
	 * will be the same as the current root) or not.
	 */
	if (readonly && pending_snapshot->snap->node !=
	    pending_snapshot->snap->commit_root) {
		trans = btrfs_join_transaction(pending_snapshot->snap);
		if (IS_ERR(trans) && PTR_ERR(trans) != -ENOENT) {
			ret = PTR_ERR(trans);
			goto fail;
		}
		if (!IS_ERR(trans)) {
			ret = btrfs_commit_transaction(trans,
						       pending_snapshot->snap);
			if (ret)
				goto fail;
		}
	}

749
	inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
750 751 752 753
	if (IS_ERR(inode)) {
		ret = PTR_ERR(inode);
		goto fail;
	}
754

755 756 757
	d_instantiate(dentry, inode);
	ret = 0;
fail:
758 759 760
	btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
					 &pending_snapshot->block_rsv,
					 pending_snapshot->qgroup_reserved);
761
free:
762
	kfree(pending_snapshot);
763 764
out:
	atomic_dec(&root->will_be_snapshoted);
C
Christoph Hellwig 已提交
765 766 767
	return ret;
}

768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787
/*  copy of may_delete in fs/namei.c()
 *	Check whether we can remove a link victim from directory dir, check
 *  whether the type of victim is right.
 *  1. We can't do it if dir is read-only (done in permission())
 *  2. We should have write and exec permissions on dir
 *  3. We can't remove anything from append-only dir
 *  4. We can't do anything with immutable dir (done in permission())
 *  5. If the sticky bit on dir is set we should either
 *	a. be owner of dir, or
 *	b. be owner of victim, or
 *	c. have CAP_FOWNER capability
 *  6. If the victim is append-only or immutable we can't do antyhing with
 *     links pointing to it.
 *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 *  9. We can't remove a root or mountpoint.
 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 *     nfs_async_unlink().
 */

788
static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
789 790 791 792 793 794 795
{
	int error;

	if (!victim->d_inode)
		return -ENOENT;

	BUG_ON(victim->d_parent->d_inode != dir);
796
	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
797 798 799 800 801 802

	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		return error;
	if (IS_APPEND(dir))
		return -EPERM;
M
Miklos Szeredi 已提交
803
	if (check_sticky(dir, victim->d_inode) || IS_APPEND(victim->d_inode) ||
804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819
	    IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
		return -EPERM;
	if (isdir) {
		if (!S_ISDIR(victim->d_inode->i_mode))
			return -ENOTDIR;
		if (IS_ROOT(victim))
			return -EBUSY;
	} else if (S_ISDIR(victim->d_inode->i_mode))
		return -EISDIR;
	if (IS_DEADDIR(dir))
		return -ENOENT;
	if (victim->d_flags & DCACHE_NFSFS_RENAMED)
		return -EBUSY;
	return 0;
}

820 821 822 823 824 825 826 827 828 829 830 831 832 833 834
/* copy of may_create in fs/namei.c() */
static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
{
	if (child->d_inode)
		return -EEXIST;
	if (IS_DEADDIR(dir))
		return -ENOENT;
	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
}

/*
 * Create a new subvolume below @parent.  This is largely modeled after
 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 * inside this filesystem so it's quite a bit simpler.
 */
835 836
static noinline int btrfs_mksubvol(struct path *parent,
				   char *name, int namelen,
S
Sage Weil 已提交
837
				   struct btrfs_root *snap_src,
A
Arne Jansen 已提交
838
				   u64 *async_transid, bool readonly,
839
				   struct btrfs_qgroup_inherit *inherit)
840
{
841
	struct inode *dir  = parent->dentry->d_inode;
842 843 844
	struct dentry *dentry;
	int error;

845 846 847
	error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
	if (error == -EINTR)
		return error;
848 849 850 851 852 853 854 855 856 857

	dentry = lookup_one_len(name, parent->dentry, namelen);
	error = PTR_ERR(dentry);
	if (IS_ERR(dentry))
		goto out_unlock;

	error = -EEXIST;
	if (dentry->d_inode)
		goto out_dput;

858
	error = btrfs_may_create(dir, dentry);
859
	if (error)
860
		goto out_dput;
861

C
Chris Mason 已提交
862 863 864 865 866 867 868 869 870 871
	/*
	 * even if this name doesn't exist, we may get hash collisions.
	 * check for them now when we can safely fail
	 */
	error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
					       dir->i_ino, name,
					       namelen);
	if (error)
		goto out_dput;

872 873 874 875 876
	down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);

	if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
		goto out_up_read;

877
	if (snap_src) {
878
		error = create_snapshot(snap_src, dir, dentry, name, namelen,
A
Arne Jansen 已提交
879
					async_transid, readonly, inherit);
880
	} else {
881 882
		error = create_subvol(dir, dentry, name, namelen,
				      async_transid, inherit);
883
	}
884 885 886 887
	if (!error)
		fsnotify_mkdir(dir, dentry);
out_up_read:
	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
888 889 890
out_dput:
	dput(dentry);
out_unlock:
891
	mutex_unlock(&dir->i_mutex);
892 893 894
	return error;
}

C
Chris Mason 已提交
895 896 897 898 899 900 901
/*
 * When we're defragging a range, we don't want to kick it off again
 * if it is really just waiting for delalloc to send it down.
 * If we find a nice big extent or delalloc range for the bytes in the
 * file you want to defrag, we return 0 to let you know to skip this
 * part of the file
 */
902
static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
C
Chris Mason 已提交
903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936
{
	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
	struct extent_map *em = NULL;
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
	u64 end;

	read_lock(&em_tree->lock);
	em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
	read_unlock(&em_tree->lock);

	if (em) {
		end = extent_map_end(em);
		free_extent_map(em);
		if (end - offset > thresh)
			return 0;
	}
	/* if we already have a nice delalloc here, just stop */
	thresh /= 2;
	end = count_range_bits(io_tree, &offset, offset + thresh,
			       thresh, EXTENT_DELALLOC, 1);
	if (end >= thresh)
		return 0;
	return 1;
}

/*
 * helper function to walk through a file and find extents
 * newer than a specific transid, and smaller than thresh.
 *
 * This is used by the defragging code to find new and small
 * extents
 */
static int find_new_extents(struct btrfs_root *root,
			    struct inode *inode, u64 newer_than,
937
			    u64 *off, u32 thresh)
C
Chris Mason 已提交
938 939 940 941 942 943 944
{
	struct btrfs_path *path;
	struct btrfs_key min_key;
	struct extent_buffer *leaf;
	struct btrfs_file_extent_item *extent;
	int type;
	int ret;
945
	u64 ino = btrfs_ino(inode);
C
Chris Mason 已提交
946 947 948 949 950

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

951
	min_key.objectid = ino;
C
Chris Mason 已提交
952 953 954
	min_key.type = BTRFS_EXTENT_DATA_KEY;
	min_key.offset = *off;

955
	while (1) {
956
		ret = btrfs_search_forward(root, &min_key, path, newer_than);
C
Chris Mason 已提交
957 958
		if (ret != 0)
			goto none;
959
process_slot:
960
		if (min_key.objectid != ino)
C
Chris Mason 已提交
961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977
			goto none;
		if (min_key.type != BTRFS_EXTENT_DATA_KEY)
			goto none;

		leaf = path->nodes[0];
		extent = btrfs_item_ptr(leaf, path->slots[0],
					struct btrfs_file_extent_item);

		type = btrfs_file_extent_type(leaf, extent);
		if (type == BTRFS_FILE_EXTENT_REG &&
		    btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
		    check_defrag_in_cache(inode, min_key.offset, thresh)) {
			*off = min_key.offset;
			btrfs_free_path(path);
			return 0;
		}

978 979 980 981 982 983
		path->slots[0]++;
		if (path->slots[0] < btrfs_header_nritems(leaf)) {
			btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
			goto process_slot;
		}

C
Chris Mason 已提交
984 985 986 987 988 989 990 991 992 993 994
		if (min_key.offset == (u64)-1)
			goto none;

		min_key.offset++;
		btrfs_release_path(path);
	}
none:
	btrfs_free_path(path);
	return -ENOENT;
}

L
Li Zefan 已提交
995
static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
996 997
{
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
L
Li Zefan 已提交
998 999 1000
	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
	struct extent_map *em;
	u64 len = PAGE_CACHE_SIZE;
1001

L
Li Zefan 已提交
1002 1003 1004 1005
	/*
	 * hopefully we have this extent in the tree already, try without
	 * the full extent lock
	 */
1006
	read_lock(&em_tree->lock);
L
Li Zefan 已提交
1007
	em = lookup_extent_mapping(em_tree, start, len);
1008 1009
	read_unlock(&em_tree->lock);

L
Li Zefan 已提交
1010
	if (!em) {
1011 1012 1013
		struct extent_state *cached = NULL;
		u64 end = start + len - 1;

L
Li Zefan 已提交
1014
		/* get the big lock and read metadata off disk */
1015
		lock_extent_bits(io_tree, start, end, 0, &cached);
L
Li Zefan 已提交
1016
		em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1017
		unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
L
Li Zefan 已提交
1018 1019 1020 1021 1022 1023 1024

		if (IS_ERR(em))
			return NULL;
	}

	return em;
}
1025

L
Li Zefan 已提交
1026 1027 1028 1029 1030 1031 1032 1033 1034 1035
static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
{
	struct extent_map *next;
	bool ret = true;

	/* this is the last extent */
	if (em->start + em->len >= i_size_read(inode))
		return false;

	next = defrag_lookup_extent(inode, em->start + em->len);
1036 1037 1038 1039
	if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
		ret = false;
	else if ((em->block_start + em->block_len == next->block_start) &&
		 (em->block_len > 128 * 1024 && next->block_len > 128 * 1024))
L
Li Zefan 已提交
1040 1041 1042
		ret = false;

	free_extent_map(next);
1043 1044 1045
	return ret;
}

1046
static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1047 1048
			       u64 *last_len, u64 *skip, u64 *defrag_end,
			       int compress)
1049
{
L
Li Zefan 已提交
1050
	struct extent_map *em;
1051
	int ret = 1;
L
Li Zefan 已提交
1052
	bool next_mergeable = true;
1053 1054

	/*
1055
	 * make sure that once we start defragging an extent, we keep on
1056 1057 1058 1059 1060 1061 1062
	 * defragging it
	 */
	if (start < *defrag_end)
		return 1;

	*skip = 0;

L
Li Zefan 已提交
1063 1064 1065
	em = defrag_lookup_extent(inode, start);
	if (!em)
		return 0;
1066 1067

	/* this will cover holes, and inline extents */
1068
	if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1069
		ret = 0;
1070 1071 1072
		goto out;
	}

L
Li Zefan 已提交
1073
	next_mergeable = defrag_check_next_extent(inode, em);
1074
	/*
L
Li Zefan 已提交
1075 1076
	 * we hit a real extent, if it is big or the next extent is not a
	 * real extent, don't bother defragging it
1077
	 */
1078
	if (!compress && (*last_len == 0 || *last_len >= thresh) &&
L
Li Zefan 已提交
1079
	    (em->len >= thresh || !next_mergeable))
1080
		ret = 0;
1081
out:
1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101
	/*
	 * last_len ends up being a counter of how many bytes we've defragged.
	 * every time we choose not to defrag an extent, we reset *last_len
	 * so that the next tiny extent will force a defrag.
	 *
	 * The end result of this is that tiny extents before a single big
	 * extent will force at least part of that big extent to be defragged.
	 */
	if (ret) {
		*defrag_end = extent_map_end(em);
	} else {
		*last_len = 0;
		*skip = extent_map_end(em);
		*defrag_end = 0;
	}

	free_extent_map(em);
	return ret;
}

C
Chris Mason 已提交
1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116
/*
 * it doesn't do much good to defrag one or two pages
 * at a time.  This pulls in a nice chunk of pages
 * to COW and defrag.
 *
 * It also makes sure the delalloc code has enough
 * dirty data to avoid making new small extents as part
 * of the defrag
 *
 * It's a good idea to start RA on this range
 * before calling this.
 */
static int cluster_pages_for_defrag(struct inode *inode,
				    struct page **pages,
				    unsigned long start_index,
1117
				    unsigned long num_pages)
C
Christoph Hellwig 已提交
1118
{
C
Chris Mason 已提交
1119 1120 1121 1122
	unsigned long file_end;
	u64 isize = i_size_read(inode);
	u64 page_start;
	u64 page_end;
1123
	u64 page_cnt;
C
Chris Mason 已提交
1124 1125 1126
	int ret;
	int i;
	int i_done;
1127
	struct btrfs_ordered_extent *ordered;
C
Chris Mason 已提交
1128
	struct extent_state *cached_state = NULL;
1129
	struct extent_io_tree *tree;
1130
	gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
C
Chris Mason 已提交
1131 1132

	file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1133 1134 1135 1136
	if (!isize || start_index > file_end)
		return 0;

	page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
C
Chris Mason 已提交
1137 1138

	ret = btrfs_delalloc_reserve_space(inode,
1139
					   page_cnt << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1140 1141 1142
	if (ret)
		return ret;
	i_done = 0;
1143
	tree = &BTRFS_I(inode)->io_tree;
C
Chris Mason 已提交
1144 1145

	/* step one, lock all the pages */
1146
	for (i = 0; i < page_cnt; i++) {
C
Chris Mason 已提交
1147
		struct page *page;
1148
again:
1149
		page = find_or_create_page(inode->i_mapping,
1150
					   start_index + i, mask);
C
Chris Mason 已提交
1151 1152 1153
		if (!page)
			break;

1154 1155 1156
		page_start = page_offset(page);
		page_end = page_start + PAGE_CACHE_SIZE - 1;
		while (1) {
1157 1158
			lock_extent_bits(tree, page_start, page_end,
					 0, &cached_state);
1159 1160
			ordered = btrfs_lookup_ordered_extent(inode,
							      page_start);
1161 1162
			unlock_extent_cached(tree, page_start, page_end,
					     &cached_state, GFP_NOFS);
1163 1164 1165 1166 1167 1168 1169
			if (!ordered)
				break;

			unlock_page(page);
			btrfs_start_ordered_extent(inode, ordered, 1);
			btrfs_put_ordered_extent(ordered);
			lock_page(page);
1170 1171 1172 1173 1174 1175 1176 1177 1178
			/*
			 * we unlocked the page above, so we need check if
			 * it was released or not.
			 */
			if (page->mapping != inode->i_mapping) {
				unlock_page(page);
				page_cache_release(page);
				goto again;
			}
1179 1180
		}

C
Chris Mason 已提交
1181 1182 1183 1184 1185 1186 1187 1188 1189 1190
		if (!PageUptodate(page)) {
			btrfs_readpage(NULL, page);
			lock_page(page);
			if (!PageUptodate(page)) {
				unlock_page(page);
				page_cache_release(page);
				ret = -EIO;
				break;
			}
		}
1191 1192 1193 1194 1195 1196 1197

		if (page->mapping != inode->i_mapping) {
			unlock_page(page);
			page_cache_release(page);
			goto again;
		}

C
Chris Mason 已提交
1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217
		pages[i] = page;
		i_done++;
	}
	if (!i_done || ret)
		goto out;

	if (!(inode->i_sb->s_flags & MS_ACTIVE))
		goto out;

	/*
	 * so now we have a nice long stream of locked
	 * and up to date pages, lets wait on them
	 */
	for (i = 0; i < i_done; i++)
		wait_on_page_writeback(pages[i]);

	page_start = page_offset(pages[0]);
	page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;

	lock_extent_bits(&BTRFS_I(inode)->io_tree,
1218
			 page_start, page_end - 1, 0, &cached_state);
C
Chris Mason 已提交
1219 1220
	clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
			  page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1221 1222
			  EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
			  &cached_state, GFP_NOFS);
C
Chris Mason 已提交
1223

1224
	if (i_done != page_cnt) {
1225 1226 1227
		spin_lock(&BTRFS_I(inode)->lock);
		BTRFS_I(inode)->outstanding_extents++;
		spin_unlock(&BTRFS_I(inode)->lock);
C
Chris Mason 已提交
1228
		btrfs_delalloc_release_space(inode,
1229
				     (page_cnt - i_done) << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1230 1231 1232
	}


1233 1234
	set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
			  &cached_state, GFP_NOFS);
C
Chris Mason 已提交
1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253

	unlock_extent_cached(&BTRFS_I(inode)->io_tree,
			     page_start, page_end - 1, &cached_state,
			     GFP_NOFS);

	for (i = 0; i < i_done; i++) {
		clear_page_dirty_for_io(pages[i]);
		ClearPageChecked(pages[i]);
		set_page_extent_mapped(pages[i]);
		set_page_dirty(pages[i]);
		unlock_page(pages[i]);
		page_cache_release(pages[i]);
	}
	return i_done;
out:
	for (i = 0; i < i_done; i++) {
		unlock_page(pages[i]);
		page_cache_release(pages[i]);
	}
1254
	btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1255 1256 1257 1258 1259 1260 1261 1262 1263 1264
	return ret;

}

int btrfs_defrag_file(struct inode *inode, struct file *file,
		      struct btrfs_ioctl_defrag_range_args *range,
		      u64 newer_than, unsigned long max_to_defrag)
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct file_ra_state *ra = NULL;
C
Christoph Hellwig 已提交
1265
	unsigned long last_index;
1266
	u64 isize = i_size_read(inode);
1267 1268 1269
	u64 last_len = 0;
	u64 skip = 0;
	u64 defrag_end = 0;
C
Chris Mason 已提交
1270
	u64 newer_off = range->start;
C
Christoph Hellwig 已提交
1271
	unsigned long i;
1272
	unsigned long ra_index = 0;
C
Christoph Hellwig 已提交
1273
	int ret;
C
Chris Mason 已提交
1274
	int defrag_count = 0;
1275
	int compress_type = BTRFS_COMPRESS_ZLIB;
1276
	u32 extent_thresh = range->extent_thresh;
1277 1278
	unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
	unsigned long cluster = max_cluster;
C
Chris Mason 已提交
1279 1280 1281
	u64 new_align = ~((u64)128 * 1024 - 1);
	struct page **pages = NULL;

1282 1283 1284 1285 1286
	if (isize == 0)
		return 0;

	if (range->start >= isize)
		return -EINVAL;
1287 1288 1289 1290 1291 1292 1293

	if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
		if (range->compress_type > BTRFS_COMPRESS_TYPES)
			return -EINVAL;
		if (range->compress_type)
			compress_type = range->compress_type;
	}
C
Christoph Hellwig 已提交
1294

1295 1296
	if (extent_thresh == 0)
		extent_thresh = 256 * 1024;
1297

C
Chris Mason 已提交
1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310
	/*
	 * if we were not given a file, allocate a readahead
	 * context
	 */
	if (!file) {
		ra = kzalloc(sizeof(*ra), GFP_NOFS);
		if (!ra)
			return -ENOMEM;
		file_ra_state_init(ra, inode->i_mapping);
	} else {
		ra = &file->f_ra;
	}

1311
	pages = kmalloc_array(max_cluster, sizeof(struct page *),
C
Chris Mason 已提交
1312 1313 1314 1315 1316 1317 1318
			GFP_NOFS);
	if (!pages) {
		ret = -ENOMEM;
		goto out_ra;
	}

	/* find the last page to defrag */
C
Chris Mason 已提交
1319
	if (range->start + range->len > range->start) {
1320
		last_index = min_t(u64, isize - 1,
C
Chris Mason 已提交
1321 1322
			 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
	} else {
1323
		last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
C
Chris Mason 已提交
1324 1325
	}

C
Chris Mason 已提交
1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341
	if (newer_than) {
		ret = find_new_extents(root, inode, newer_than,
				       &newer_off, 64 * 1024);
		if (!ret) {
			range->start = newer_off;
			/*
			 * we always align our defrag to help keep
			 * the extents in the file evenly spaced
			 */
			i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
		} else
			goto out_ra;
	} else {
		i = range->start >> PAGE_CACHE_SHIFT;
	}
	if (!max_to_defrag)
L
Liu Bo 已提交
1342
		max_to_defrag = last_index + 1;
C
Chris Mason 已提交
1343

L
Li Zefan 已提交
1344 1345 1346 1347 1348 1349 1350
	/*
	 * make writeback starts from i, so the defrag range can be
	 * written sequentially.
	 */
	if (i < inode->i_mapping->writeback_index)
		inode->i_mapping->writeback_index = i;

1351
	while (i <= last_index && defrag_count < max_to_defrag &&
1352
	       (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) {
C
Chris Mason 已提交
1353 1354 1355 1356 1357 1358 1359
		/*
		 * make sure we stop running if someone unmounts
		 * the FS
		 */
		if (!(inode->i_sb->s_flags & MS_ACTIVE))
			break;

1360
		if (btrfs_defrag_cancelled(root->fs_info)) {
1361
			printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1362 1363 1364 1365
			ret = -EAGAIN;
			break;
		}

1366
		if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
L
Li Zefan 已提交
1367
					 extent_thresh, &last_len, &skip,
1368 1369
					 &defrag_end, range->flags &
					 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1370 1371 1372 1373 1374
			unsigned long next;
			/*
			 * the should_defrag function tells us how much to skip
			 * bump our counter by the suggested amount
			 */
1375
			next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE);
1376 1377 1378
			i = max(i + 1, next);
			continue;
		}
1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393

		if (!newer_than) {
			cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
				   PAGE_CACHE_SHIFT) - i;
			cluster = min(cluster, max_cluster);
		} else {
			cluster = max_cluster;
		}

		if (i + cluster > ra_index) {
			ra_index = max(i, ra_index);
			btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
				       cluster);
			ra_index += max_cluster;
		}
1394

1395
		mutex_lock(&inode->i_mutex);
1396 1397
		if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
			BTRFS_I(inode)->force_compress = compress_type;
1398
		ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1399 1400
		if (ret < 0) {
			mutex_unlock(&inode->i_mutex);
C
Chris Mason 已提交
1401
			goto out_ra;
1402
		}
C
Chris Mason 已提交
1403 1404

		defrag_count += ret;
1405
		balance_dirty_pages_ratelimited(inode->i_mapping);
1406
		mutex_unlock(&inode->i_mutex);
C
Chris Mason 已提交
1407 1408 1409 1410 1411

		if (newer_than) {
			if (newer_off == (u64)-1)
				break;

1412 1413 1414
			if (ret > 0)
				i += ret;

C
Chris Mason 已提交
1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425
			newer_off = max(newer_off + 1,
					(u64)i << PAGE_CACHE_SHIFT);

			ret = find_new_extents(root, inode,
					       newer_than, &newer_off,
					       64 * 1024);
			if (!ret) {
				range->start = newer_off;
				i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
			} else {
				break;
C
Christoph Hellwig 已提交
1426
			}
C
Chris Mason 已提交
1427
		} else {
1428
			if (ret > 0) {
L
Li Zefan 已提交
1429
				i += ret;
1430 1431
				last_len += ret << PAGE_CACHE_SHIFT;
			} else {
L
Li Zefan 已提交
1432
				i++;
1433 1434
				last_len = 0;
			}
C
Christoph Hellwig 已提交
1435 1436 1437
		}
	}

1438
	if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
C
Chris Mason 已提交
1439
		filemap_flush(inode->i_mapping);
1440 1441 1442 1443
		if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
			     &BTRFS_I(inode)->runtime_flags))
			filemap_flush(inode->i_mapping);
	}
C
Chris Mason 已提交
1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459

	if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
		/* the filemap_flush will queue IO into the worker threads, but
		 * we have to make sure the IO is actually started and that
		 * ordered extents get created before we return
		 */
		atomic_inc(&root->fs_info->async_submit_draining);
		while (atomic_read(&root->fs_info->nr_async_submits) ||
		      atomic_read(&root->fs_info->async_delalloc_pages)) {
			wait_event(root->fs_info->async_submit_wait,
			   (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
			    atomic_read(&root->fs_info->async_delalloc_pages) == 0));
		}
		atomic_dec(&root->fs_info->async_submit_draining);
	}

1460
	if (range->compress_type == BTRFS_COMPRESS_LZO) {
1461
		btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1462 1463
	}

1464
	ret = defrag_count;
1465

C
Chris Mason 已提交
1466
out_ra:
1467 1468 1469 1470 1471
	if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
		mutex_lock(&inode->i_mutex);
		BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
		mutex_unlock(&inode->i_mutex);
	}
C
Chris Mason 已提交
1472 1473 1474
	if (!file)
		kfree(ra);
	kfree(pages);
1475
	return ret;
C
Christoph Hellwig 已提交
1476 1477
}

1478
static noinline int btrfs_ioctl_resize(struct file *file,
1479
					void __user *arg)
C
Christoph Hellwig 已提交
1480 1481 1482 1483
{
	u64 new_size;
	u64 old_size;
	u64 devid = 1;
A
Al Viro 已提交
1484
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
C
Christoph Hellwig 已提交
1485 1486 1487 1488
	struct btrfs_ioctl_vol_args *vol_args;
	struct btrfs_trans_handle *trans;
	struct btrfs_device *device = NULL;
	char *sizestr;
1489
	char *retptr;
C
Christoph Hellwig 已提交
1490 1491 1492 1493
	char *devstr = NULL;
	int ret = 0;
	int mod = 0;

1494 1495 1496
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

1497 1498 1499 1500
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

1501 1502
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
1503
		mnt_drop_write_file(file);
1504
		return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1505 1506
	}

1507
	mutex_lock(&root->fs_info->volume_mutex);
L
Li Zefan 已提交
1508
	vol_args = memdup_user(arg, sizeof(*vol_args));
1509 1510 1511 1512
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
1513 1514

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
1515 1516 1517 1518 1519 1520 1521

	sizestr = vol_args->name;
	devstr = strchr(sizestr, ':');
	if (devstr) {
		sizestr = devstr + 1;
		*devstr = '\0';
		devstr = vol_args->name;
1522 1523 1524
		ret = kstrtoull(devstr, 10, &devid);
		if (ret)
			goto out_free;
1525 1526 1527 1528
		if (!devid) {
			ret = -EINVAL;
			goto out_free;
		}
1529
		btrfs_info(root->fs_info, "resizing devid %llu", devid);
C
Christoph Hellwig 已提交
1530
	}
M
Miao Xie 已提交
1531

1532
	device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
C
Christoph Hellwig 已提交
1533
	if (!device) {
1534
		btrfs_info(root->fs_info, "resizer unable to find device %llu",
1535
		       devid);
1536
		ret = -ENODEV;
1537
		goto out_free;
C
Christoph Hellwig 已提交
1538
	}
M
Miao Xie 已提交
1539 1540

	if (!device->writeable) {
1541 1542
		btrfs_info(root->fs_info,
			   "resizer unable to apply on readonly device %llu",
1543
		       devid);
1544
		ret = -EPERM;
L
Liu Bo 已提交
1545 1546 1547
		goto out_free;
	}

C
Christoph Hellwig 已提交
1548 1549 1550 1551 1552 1553 1554 1555 1556 1557
	if (!strcmp(sizestr, "max"))
		new_size = device->bdev->bd_inode->i_size;
	else {
		if (sizestr[0] == '-') {
			mod = -1;
			sizestr++;
		} else if (sizestr[0] == '+') {
			mod = 1;
			sizestr++;
		}
1558 1559
		new_size = memparse(sizestr, &retptr);
		if (*retptr != '\0' || new_size == 0) {
C
Christoph Hellwig 已提交
1560
			ret = -EINVAL;
1561
			goto out_free;
C
Christoph Hellwig 已提交
1562 1563 1564
		}
	}

1565
	if (device->is_tgtdev_for_dev_replace) {
1566
		ret = -EPERM;
1567 1568 1569
		goto out_free;
	}

1570
	old_size = btrfs_device_get_total_bytes(device);
C
Christoph Hellwig 已提交
1571 1572 1573 1574

	if (mod < 0) {
		if (new_size > old_size) {
			ret = -EINVAL;
1575
			goto out_free;
C
Christoph Hellwig 已提交
1576 1577 1578
		}
		new_size = old_size - new_size;
	} else if (mod > 0) {
1579
		if (new_size > ULLONG_MAX - old_size) {
1580
			ret = -ERANGE;
1581 1582
			goto out_free;
		}
C
Christoph Hellwig 已提交
1583 1584 1585 1586 1587
		new_size = old_size + new_size;
	}

	if (new_size < 256 * 1024 * 1024) {
		ret = -EINVAL;
1588
		goto out_free;
C
Christoph Hellwig 已提交
1589 1590 1591
	}
	if (new_size > device->bdev->bd_inode->i_size) {
		ret = -EFBIG;
1592
		goto out_free;
C
Christoph Hellwig 已提交
1593 1594 1595 1596 1597
	}

	do_div(new_size, root->sectorsize);
	new_size *= root->sectorsize;

1598
	printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1599
		      rcu_str_deref(device->name), new_size);
C
Christoph Hellwig 已提交
1600 1601

	if (new_size > old_size) {
1602
		trans = btrfs_start_transaction(root, 0);
1603 1604
		if (IS_ERR(trans)) {
			ret = PTR_ERR(trans);
1605
			goto out_free;
1606
		}
C
Christoph Hellwig 已提交
1607 1608
		ret = btrfs_grow_device(trans, device, new_size);
		btrfs_commit_transaction(trans, root);
1609
	} else if (new_size < old_size) {
C
Christoph Hellwig 已提交
1610
		ret = btrfs_shrink_device(device, new_size);
1611
	} /* equal, nothing need to do */
C
Christoph Hellwig 已提交
1612

1613
out_free:
C
Christoph Hellwig 已提交
1614
	kfree(vol_args);
1615 1616
out:
	mutex_unlock(&root->fs_info->volume_mutex);
1617
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1618
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
1619 1620 1621
	return ret;
}

S
Sage Weil 已提交
1622
static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
A
Arne Jansen 已提交
1623 1624
				char *name, unsigned long fd, int subvol,
				u64 *transid, bool readonly,
1625
				struct btrfs_qgroup_inherit *inherit)
C
Christoph Hellwig 已提交
1626 1627
{
	int namelen;
1628
	int ret = 0;
C
Christoph Hellwig 已提交
1629

1630 1631 1632 1633
	ret = mnt_want_write_file(file);
	if (ret)
		goto out;

S
Sage Weil 已提交
1634 1635
	namelen = strlen(name);
	if (strchr(name, '/')) {
C
Christoph Hellwig 已提交
1636
		ret = -EINVAL;
1637
		goto out_drop_write;
C
Christoph Hellwig 已提交
1638 1639
	}

1640 1641 1642
	if (name[0] == '.' &&
	   (namelen == 1 || (name[1] == '.' && namelen == 2))) {
		ret = -EEXIST;
1643
		goto out_drop_write;
1644 1645
	}

1646
	if (subvol) {
S
Sage Weil 已提交
1647
		ret = btrfs_mksubvol(&file->f_path, name, namelen,
A
Arne Jansen 已提交
1648
				     NULL, transid, readonly, inherit);
1649
	} else {
1650
		struct fd src = fdget(fd);
1651
		struct inode *src_inode;
1652
		if (!src.file) {
1653
			ret = -EINVAL;
1654
			goto out_drop_write;
1655 1656
		}

A
Al Viro 已提交
1657 1658
		src_inode = file_inode(src.file);
		if (src_inode->i_sb != file_inode(file)->i_sb) {
1659 1660
			btrfs_info(BTRFS_I(src_inode)->root->fs_info,
				   "Snapshot src from another FS");
1661
			ret = -EXDEV;
1662 1663 1664 1665 1666 1667
		} else if (!inode_owner_or_capable(src_inode)) {
			/*
			 * Subvolume creation is not restricted, but snapshots
			 * are limited to own subvolumes only
			 */
			ret = -EPERM;
1668 1669 1670 1671
		} else {
			ret = btrfs_mksubvol(&file->f_path, name, namelen,
					     BTRFS_I(src_inode)->root,
					     transid, readonly, inherit);
1672
		}
1673
		fdput(src);
1674
	}
1675 1676
out_drop_write:
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
1677
out:
S
Sage Weil 已提交
1678 1679 1680 1681
	return ret;
}

static noinline int btrfs_ioctl_snap_create(struct file *file,
1682
					    void __user *arg, int subvol)
S
Sage Weil 已提交
1683
{
1684
	struct btrfs_ioctl_vol_args *vol_args;
S
Sage Weil 已提交
1685 1686
	int ret;

1687 1688 1689 1690
	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';
S
Sage Weil 已提交
1691

1692
	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
L
Li Zefan 已提交
1693
					      vol_args->fd, subvol,
A
Arne Jansen 已提交
1694
					      NULL, false, NULL);
1695

1696 1697 1698
	kfree(vol_args);
	return ret;
}
1699

1700 1701 1702 1703 1704 1705 1706
static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
					       void __user *arg, int subvol)
{
	struct btrfs_ioctl_vol_args_v2 *vol_args;
	int ret;
	u64 transid = 0;
	u64 *ptr = NULL;
L
Li Zefan 已提交
1707
	bool readonly = false;
A
Arne Jansen 已提交
1708
	struct btrfs_qgroup_inherit *inherit = NULL;
1709

1710 1711 1712 1713
	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';
1714

L
Li Zefan 已提交
1715
	if (vol_args->flags &
A
Arne Jansen 已提交
1716 1717
	    ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
	      BTRFS_SUBVOL_QGROUP_INHERIT)) {
L
Li Zefan 已提交
1718
		ret = -EOPNOTSUPP;
D
Dan Carpenter 已提交
1719
		goto free_args;
S
Sage Weil 已提交
1720
	}
1721 1722 1723

	if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
		ptr = &transid;
L
Li Zefan 已提交
1724 1725
	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
		readonly = true;
A
Arne Jansen 已提交
1726 1727 1728
	if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
		if (vol_args->size > PAGE_CACHE_SIZE) {
			ret = -EINVAL;
D
Dan Carpenter 已提交
1729
			goto free_args;
A
Arne Jansen 已提交
1730 1731 1732 1733
		}
		inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
		if (IS_ERR(inherit)) {
			ret = PTR_ERR(inherit);
D
Dan Carpenter 已提交
1734
			goto free_args;
A
Arne Jansen 已提交
1735 1736
		}
	}
1737 1738

	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
A
Arne Jansen 已提交
1739
					      vol_args->fd, subvol, ptr,
1740
					      readonly, inherit);
D
Dan Carpenter 已提交
1741 1742
	if (ret)
		goto free_inherit;
1743

D
Dan Carpenter 已提交
1744 1745 1746 1747
	if (ptr && copy_to_user(arg +
				offsetof(struct btrfs_ioctl_vol_args_v2,
					transid),
				ptr, sizeof(*ptr)))
1748
		ret = -EFAULT;
D
Dan Carpenter 已提交
1749 1750

free_inherit:
A
Arne Jansen 已提交
1751
	kfree(inherit);
D
Dan Carpenter 已提交
1752 1753
free_args:
	kfree(vol_args);
C
Christoph Hellwig 已提交
1754 1755 1756
	return ret;
}

1757 1758 1759
static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
						void __user *arg)
{
A
Al Viro 已提交
1760
	struct inode *inode = file_inode(file);
1761 1762 1763 1764
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret = 0;
	u64 flags = 0;

L
Li Zefan 已提交
1765
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781
		return -EINVAL;

	down_read(&root->fs_info->subvol_sem);
	if (btrfs_root_readonly(root))
		flags |= BTRFS_SUBVOL_RDONLY;
	up_read(&root->fs_info->subvol_sem);

	if (copy_to_user(arg, &flags, sizeof(flags)))
		ret = -EFAULT;

	return ret;
}

static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
					      void __user *arg)
{
A
Al Viro 已提交
1782
	struct inode *inode = file_inode(file);
1783 1784 1785 1786 1787 1788
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
	u64 root_flags;
	u64 flags;
	int ret = 0;

1789 1790 1791
	if (!inode_owner_or_capable(inode))
		return -EPERM;

1792 1793 1794
	ret = mnt_want_write_file(file);
	if (ret)
		goto out;
1795

1796 1797 1798 1799
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
		ret = -EINVAL;
		goto out_drop_write;
	}
1800

1801 1802 1803 1804
	if (copy_from_user(&flags, arg, sizeof(flags))) {
		ret = -EFAULT;
		goto out_drop_write;
	}
1805

1806 1807 1808 1809
	if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
		ret = -EINVAL;
		goto out_drop_write;
	}
1810

1811 1812 1813 1814
	if (flags & ~BTRFS_SUBVOL_RDONLY) {
		ret = -EOPNOTSUPP;
		goto out_drop_write;
	}
1815 1816 1817 1818 1819

	down_write(&root->fs_info->subvol_sem);

	/* nothing to do */
	if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1820
		goto out_drop_sem;
1821 1822

	root_flags = btrfs_root_flags(&root->root_item);
1823
	if (flags & BTRFS_SUBVOL_RDONLY) {
1824 1825
		btrfs_set_root_flags(&root->root_item,
				     root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1826 1827 1828 1829 1830 1831 1832 1833
	} 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,
1834
				     root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1835 1836 1837 1838 1839 1840 1841 1842 1843 1844
			spin_unlock(&root->root_item_lock);
		} else {
			spin_unlock(&root->root_item_lock);
			btrfs_warn(root->fs_info,
			"Attempt to set subvolume %llu read-write during send",
					root->root_key.objectid);
			ret = -EPERM;
			goto out_drop_sem;
		}
	}
1845 1846 1847 1848 1849 1850 1851

	trans = btrfs_start_transaction(root, 1);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out_reset;
	}

1852
	ret = btrfs_update_root(trans, root->fs_info->tree_root,
1853 1854 1855 1856 1857 1858
				&root->root_key, &root->root_item);

	btrfs_commit_transaction(trans, root);
out_reset:
	if (ret)
		btrfs_set_root_flags(&root->root_item, root_flags);
1859
out_drop_sem:
1860
	up_write(&root->fs_info->subvol_sem);
1861 1862 1863
out_drop_write:
	mnt_drop_write_file(file);
out:
1864 1865 1866
	return ret;
}

1867 1868 1869 1870 1871 1872
/*
 * helper to check if the subvolume references other subvolumes
 */
static noinline int may_destroy_subvol(struct btrfs_root *root)
{
	struct btrfs_path *path;
1873
	struct btrfs_dir_item *di;
1874
	struct btrfs_key key;
1875
	u64 dir_id;
1876 1877 1878 1879 1880 1881
	int ret;

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

1882 1883 1884 1885 1886 1887 1888
	/* Make sure this root isn't set as the default subvol */
	dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
	di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
				   dir_id, "default", 7, 0);
	if (di && !IS_ERR(di)) {
		btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
		if (key.objectid == root->root_key.objectid) {
1889 1890 1891
			ret = -EPERM;
			btrfs_err(root->fs_info, "deleting default subvolume "
				  "%llu is not allowed", key.objectid);
1892 1893 1894 1895 1896
			goto out;
		}
		btrfs_release_path(path);
	}

1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919
	key.objectid = root->root_key.objectid;
	key.type = BTRFS_ROOT_REF_KEY;
	key.offset = (u64)-1;

	ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
				&key, path, 0, 0);
	if (ret < 0)
		goto out;
	BUG_ON(ret == 0);

	ret = 0;
	if (path->slots[0] > 0) {
		path->slots[0]--;
		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
		if (key.objectid == root->root_key.objectid &&
		    key.type == BTRFS_ROOT_REF_KEY)
			ret = -ENOTEMPTY;
	}
out:
	btrfs_free_path(path);
	return ret;
}

1920 1921 1922
static noinline int key_in_sk(struct btrfs_key *key,
			      struct btrfs_ioctl_search_key *sk)
{
1923 1924 1925 1926 1927 1928 1929 1930 1931
	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)
1932
		return 0;
1933 1934 1935 1936 1937 1938 1939

	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)
1940 1941 1942 1943 1944 1945 1946 1947
		return 0;
	return 1;
}

static noinline int copy_to_sk(struct btrfs_root *root,
			       struct btrfs_path *path,
			       struct btrfs_key *key,
			       struct btrfs_ioctl_search_key *sk,
1948
			       size_t *buf_size,
1949
			       char __user *ubuf,
1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976
			       unsigned long *sk_offset,
			       int *num_found)
{
	u64 found_transid;
	struct extent_buffer *leaf;
	struct btrfs_ioctl_search_header sh;
	unsigned long item_off;
	unsigned long item_len;
	int nritems;
	int i;
	int slot;
	int ret = 0;

	leaf = path->nodes[0];
	slot = path->slots[0];
	nritems = btrfs_header_nritems(leaf);

	if (btrfs_header_generation(leaf) > sk->max_transid) {
		i = nritems;
		goto advance_key;
	}
	found_transid = btrfs_header_generation(leaf);

	for (i = slot; i < nritems; i++) {
		item_off = btrfs_item_ptr_offset(leaf, i);
		item_len = btrfs_item_size_nr(leaf, i);

1977 1978 1979 1980
		btrfs_item_key_to_cpu(leaf, key, i);
		if (!key_in_sk(key, sk))
			continue;

1981
		if (sizeof(sh) + item_len > *buf_size) {
1982 1983 1984 1985 1986 1987 1988 1989 1990 1991
			if (*num_found) {
				ret = 1;
				goto out;
			}

			/*
			 * return one empty item back for v1, which does not
			 * handle -EOVERFLOW
			 */

1992
			*buf_size = sizeof(sh) + item_len;
1993
			item_len = 0;
1994 1995
			ret = -EOVERFLOW;
		}
1996

1997
		if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
1998
			ret = 1;
1999
			goto out;
2000 2001 2002 2003 2004 2005 2006 2007 2008
		}

		sh.objectid = key->objectid;
		sh.offset = key->offset;
		sh.type = key->type;
		sh.len = item_len;
		sh.transid = found_transid;

		/* copy search result header */
2009 2010 2011 2012 2013
		if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
			ret = -EFAULT;
			goto out;
		}

2014 2015 2016
		*sk_offset += sizeof(sh);

		if (item_len) {
2017
			char __user *up = ubuf + *sk_offset;
2018
			/* copy the item */
2019 2020 2021 2022 2023 2024
			if (read_extent_buffer_to_user(leaf, up,
						       item_off, item_len)) {
				ret = -EFAULT;
				goto out;
			}

2025 2026
			*sk_offset += item_len;
		}
2027
		(*num_found)++;
2028

2029 2030 2031
		if (ret) /* -EOVERFLOW from above */
			goto out;

2032 2033 2034 2035
		if (*num_found >= sk->nr_items) {
			ret = 1;
			goto out;
		}
2036 2037
	}
advance_key:
2038 2039
	ret = 0;
	if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2040
		key->offset++;
2041 2042
	else if (key->type < (u8)-1 && key->type < sk->max_type) {
		key->offset = 0;
2043
		key->type++;
2044 2045 2046
	} else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
		key->offset = 0;
		key->type = 0;
2047
		key->objectid++;
2048 2049
	} else
		ret = 1;
2050
out:
2051 2052 2053 2054 2055 2056 2057 2058 2059
	/*
	 *  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
	 */
2060 2061 2062 2063
	return ret;
}

static noinline int search_ioctl(struct inode *inode,
2064
				 struct btrfs_ioctl_search_key *sk,
2065
				 size_t *buf_size,
2066
				 char __user *ubuf)
2067 2068 2069 2070 2071 2072 2073 2074 2075
{
	struct btrfs_root *root;
	struct btrfs_key key;
	struct btrfs_path *path;
	struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
	int ret;
	int num_found = 0;
	unsigned long sk_offset = 0;

2076 2077
	if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
		*buf_size = sizeof(struct btrfs_ioctl_search_header);
2078
		return -EOVERFLOW;
2079
	}
2080

2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093
	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

	if (sk->tree_id == 0) {
		/* search the root of the inode that was passed */
		root = BTRFS_I(inode)->root;
	} else {
		key.objectid = sk->tree_id;
		key.type = BTRFS_ROOT_ITEM_KEY;
		key.offset = (u64)-1;
		root = btrfs_read_fs_root_no_name(info, &key);
		if (IS_ERR(root)) {
2094
			printk(KERN_ERR "BTRFS: could not find root %llu\n",
2095 2096 2097 2098 2099 2100 2101 2102 2103 2104
			       sk->tree_id);
			btrfs_free_path(path);
			return -ENOENT;
		}
	}

	key.objectid = sk->min_objectid;
	key.type = sk->min_type;
	key.offset = sk->min_offset;

2105
	while (1) {
2106
		ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2107 2108 2109 2110 2111
		if (ret != 0) {
			if (ret > 0)
				ret = 0;
			goto err;
		}
2112
		ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2113
				 &sk_offset, &num_found);
2114
		btrfs_release_path(path);
2115
		if (ret)
2116 2117 2118
			break;

	}
2119 2120
	if (ret > 0)
		ret = 0;
2121 2122 2123 2124 2125 2126 2127 2128 2129
err:
	sk->nr_items = num_found;
	btrfs_free_path(path);
	return ret;
}

static noinline int btrfs_ioctl_tree_search(struct file *file,
					   void __user *argp)
{
2130 2131
	struct btrfs_ioctl_search_args __user *uargs;
	struct btrfs_ioctl_search_key sk;
2132 2133 2134
	struct inode *inode;
	int ret;
	size_t buf_size;
2135 2136 2137 2138

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2139 2140 2141 2142
	uargs = (struct btrfs_ioctl_search_args __user *)argp;

	if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
		return -EFAULT;
2143

2144
	buf_size = sizeof(uargs->buf);
2145

A
Al Viro 已提交
2146
	inode = file_inode(file);
2147
	ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2148 2149 2150 2151 2152 2153 2154 2155

	/*
	 * 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;

2156
	if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2157 2158 2159 2160
		ret = -EFAULT;
	return ret;
}

G
Gerhard Heift 已提交
2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196
static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
					       void __user *argp)
{
	struct btrfs_ioctl_search_args_v2 __user *uarg;
	struct btrfs_ioctl_search_args_v2 args;
	struct inode *inode;
	int ret;
	size_t buf_size;
	const size_t buf_limit = 16 * 1024 * 1024;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	/* copy search header and buffer size */
	uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
	if (copy_from_user(&args, uarg, sizeof(args)))
		return -EFAULT;

	buf_size = args.buf_size;

	if (buf_size < sizeof(struct btrfs_ioctl_search_header))
		return -EOVERFLOW;

	/* limit result size to 16MB */
	if (buf_size > buf_limit)
		buf_size = buf_limit;

	inode = file_inode(file);
	ret = search_ioctl(inode, &args.key, &buf_size,
			   (char *)(&uarg->buf[0]));
	if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
		ret = -EFAULT;
	else if (ret == -EOVERFLOW &&
		copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
		ret = -EFAULT;

2197 2198 2199
	return ret;
}

2200
/*
2201 2202 2203
 * Search INODE_REFs to identify path name of 'dirid' directory
 * in a 'tree_id' tree. and sets path name to 'name'.
 */
2204 2205 2206 2207 2208
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;
2209
	char *ptr;
2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226
	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;

2227
	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2228 2229 2230 2231 2232 2233

	key.objectid = tree_id;
	key.type = BTRFS_ROOT_ITEM_KEY;
	key.offset = (u64)-1;
	root = btrfs_read_fs_root_no_name(info, &key);
	if (IS_ERR(root)) {
2234
		printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2235 2236
		ret = -ENOENT;
		goto out;
2237 2238 2239 2240
	}

	key.objectid = dirid;
	key.type = BTRFS_INODE_REF_KEY;
2241
	key.offset = (u64)-1;
2242

2243
	while (1) {
2244 2245 2246
		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
		if (ret < 0)
			goto out;
2247 2248 2249 2250 2251 2252 2253 2254 2255 2256
		else if (ret > 0) {
			ret = btrfs_previous_item(root, path, dirid,
						  BTRFS_INODE_REF_KEY);
			if (ret < 0)
				goto out;
			else if (ret > 0) {
				ret = -ENOENT;
				goto out;
			}
		}
2257 2258 2259 2260 2261 2262 2263 2264 2265

		l = path->nodes[0];
		slot = path->slots[0];
		btrfs_item_key_to_cpu(l, &key, slot);

		iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
		len = btrfs_inode_ref_name_len(l, iref);
		ptr -= len + 1;
		total_len += len + 1;
2266 2267
		if (ptr < name) {
			ret = -ENAMETOOLONG;
2268
			goto out;
2269
		}
2270 2271

		*(ptr + len) = '/';
2272
		read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2273 2274 2275 2276

		if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
			break;

2277
		btrfs_release_path(path);
2278
		key.objectid = key.offset;
2279
		key.offset = (u64)-1;
2280 2281
		dirid = key.objectid;
	}
2282
	memmove(name, ptr, total_len);
2283
	name[total_len] = '\0';
2284 2285 2286
	ret = 0;
out:
	btrfs_free_path(path);
2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299
	return ret;
}

static noinline int btrfs_ioctl_ino_lookup(struct file *file,
					   void __user *argp)
{
	 struct btrfs_ioctl_ino_lookup_args *args;
	 struct inode *inode;
	 int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

J
Julia Lawall 已提交
2300 2301 2302
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
2303

A
Al Viro 已提交
2304
	inode = file_inode(file);
2305

2306 2307 2308
	if (args->treeid == 0)
		args->treeid = BTRFS_I(inode)->root->root_key.objectid;

2309 2310 2311 2312 2313 2314 2315 2316
	ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
					args->treeid, args->objectid,
					args->name);

	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
		ret = -EFAULT;

	kfree(args);
2317 2318 2319
	return ret;
}

2320 2321 2322
static noinline int btrfs_ioctl_snap_destroy(struct file *file,
					     void __user *arg)
{
A
Al Viro 已提交
2323
	struct dentry *parent = file->f_path.dentry;
2324 2325 2326 2327 2328 2329 2330
	struct dentry *dentry;
	struct inode *dir = parent->d_inode;
	struct inode *inode;
	struct btrfs_root *root = BTRFS_I(dir)->root;
	struct btrfs_root *dest = NULL;
	struct btrfs_ioctl_vol_args *vol_args;
	struct btrfs_trans_handle *trans;
2331
	struct btrfs_block_rsv block_rsv;
2332
	u64 root_flags;
2333
	u64 qgroup_reserved;
2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349
	int namelen;
	int ret;
	int err = 0;

	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
	namelen = strlen(vol_args->name);
	if (strchr(vol_args->name, '/') ||
	    strncmp(vol_args->name, "..", namelen) == 0) {
		err = -EINVAL;
		goto out;
	}

2350
	err = mnt_want_write_file(file);
2351 2352 2353
	if (err)
		goto out;

2354

2355 2356
	err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
	if (err == -EINTR)
2357
		goto out_drop_write;
2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369
	dentry = lookup_one_len(vol_args->name, parent, namelen);
	if (IS_ERR(dentry)) {
		err = PTR_ERR(dentry);
		goto out_unlock_dir;
	}

	if (!dentry->d_inode) {
		err = -ENOENT;
		goto out_dput;
	}

	inode = dentry->d_inode;
2370
	dest = BTRFS_I(inode)->root;
2371
	if (!capable(CAP_SYS_ADMIN)) {
2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404
		/*
		 * Regular user.  Only allow this with a special mount
		 * option, when the user has write+exec access to the
		 * subvol root, and when rmdir(2) would have been
		 * allowed.
		 *
		 * Note that this is _not_ check that the subvol is
		 * empty or doesn't contain data that we wouldn't
		 * otherwise be able to delete.
		 *
		 * Users who want to delete empty subvols should try
		 * rmdir(2).
		 */
		err = -EPERM;
		if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
			goto out_dput;

		/*
		 * Do not allow deletion if the parent dir is the same
		 * as the dir to be deleted.  That means the ioctl
		 * must be called on the dentry referencing the root
		 * of the subvol, not a random directory contained
		 * within it.
		 */
		err = -EINVAL;
		if (root == dest)
			goto out_dput;

		err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
		if (err)
			goto out_dput;
	}

2405 2406 2407 2408 2409
	/* check if subvolume may be deleted by a user */
	err = btrfs_may_delete(dir, dentry, 1);
	if (err)
		goto out_dput;

L
Li Zefan 已提交
2410
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2411 2412 2413 2414 2415
		err = -EINVAL;
		goto out_dput;
	}

	mutex_lock(&inode->i_mutex);
2416 2417 2418 2419 2420 2421 2422

	/*
	 * Don't allow to delete a subvolume with send in progress. This is
	 * inside the i_mutex so the error handling that has to drop the bit
	 * again is not run concurrently.
	 */
	spin_lock(&dest->root_item_lock);
2423 2424 2425
	root_flags = btrfs_root_flags(&dest->root_item);
	if (dest->send_in_progress == 0) {
		btrfs_set_root_flags(&dest->root_item,
2426 2427 2428 2429 2430 2431
				root_flags | BTRFS_ROOT_SUBVOL_DEAD);
		spin_unlock(&dest->root_item_lock);
	} else {
		spin_unlock(&dest->root_item_lock);
		btrfs_warn(root->fs_info,
			"Attempt to delete subvolume %llu during send",
2432
			dest->root_key.objectid);
2433 2434 2435 2436
		err = -EPERM;
		goto out_dput;
	}

2437
	d_invalidate(dentry);
2438 2439 2440 2441 2442 2443 2444

	down_write(&root->fs_info->subvol_sem);

	err = may_destroy_subvol(dest);
	if (err)
		goto out_up_write;

2445 2446 2447 2448 2449 2450
	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
	/*
	 * One for dir inode, two for dir entries, two for root
	 * ref/backref.
	 */
	err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2451
					       5, &qgroup_reserved, true);
2452 2453 2454
	if (err)
		goto out_up_write;

2455 2456 2457
	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		err = PTR_ERR(trans);
2458
		goto out_release;
2459
	}
2460 2461
	trans->block_rsv = &block_rsv;
	trans->bytes_reserved = block_rsv.size;
2462

2463 2464 2465 2466
	ret = btrfs_unlink_subvol(trans, root, dir,
				dest->root_key.objectid,
				dentry->d_name.name,
				dentry->d_name.len);
2467 2468 2469 2470 2471
	if (ret) {
		err = ret;
		btrfs_abort_transaction(trans, root, ret);
		goto out_end_trans;
	}
2472 2473 2474 2475 2476 2477 2478 2479

	btrfs_record_root_in_trans(trans, dest);

	memset(&dest->root_item.drop_progress, 0,
		sizeof(dest->root_item.drop_progress));
	dest->root_item.drop_level = 0;
	btrfs_set_root_refs(&dest->root_item, 0);

2480
	if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2481 2482 2483
		ret = btrfs_insert_orphan_item(trans,
					root->fs_info->tree_root,
					dest->root_key.objectid);
2484 2485 2486 2487 2488
		if (ret) {
			btrfs_abort_transaction(trans, root, ret);
			err = ret;
			goto out_end_trans;
		}
2489
	}
2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510

	ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
				  dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
				  dest->root_key.objectid);
	if (ret && ret != -ENOENT) {
		btrfs_abort_transaction(trans, root, ret);
		err = ret;
		goto out_end_trans;
	}
	if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
		ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
					  dest->root_item.received_uuid,
					  BTRFS_UUID_KEY_RECEIVED_SUBVOL,
					  dest->root_key.objectid);
		if (ret && ret != -ENOENT) {
			btrfs_abort_transaction(trans, root, ret);
			err = ret;
			goto out_end_trans;
		}
	}

2511
out_end_trans:
2512 2513
	trans->block_rsv = NULL;
	trans->bytes_reserved = 0;
S
Sage Weil 已提交
2514
	ret = btrfs_end_transaction(trans, root);
2515 2516
	if (ret && !err)
		err = ret;
2517
	inode->i_flags |= S_DEAD;
2518 2519
out_release:
	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2520 2521
out_up_write:
	up_write(&root->fs_info->subvol_sem);
2522 2523
	if (err) {
		spin_lock(&dest->root_item_lock);
2524 2525
		root_flags = btrfs_root_flags(&dest->root_item);
		btrfs_set_root_flags(&dest->root_item,
2526 2527 2528
				root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
		spin_unlock(&dest->root_item_lock);
	}
2529 2530
	mutex_unlock(&inode->i_mutex);
	if (!err) {
2531
		shrink_dcache_sb(root->fs_info->sb);
2532 2533
		btrfs_invalidate_inodes(dest);
		d_delete(dentry);
2534
		ASSERT(dest->send_in_progress == 0);
2535 2536

		/* the last ref */
2537 2538 2539
		if (dest->ino_cache_inode) {
			iput(dest->ino_cache_inode);
			dest->ino_cache_inode = NULL;
2540
		}
2541 2542 2543 2544 2545
	}
out_dput:
	dput(dentry);
out_unlock_dir:
	mutex_unlock(&dir->i_mutex);
2546
out_drop_write:
A
Al Viro 已提交
2547
	mnt_drop_write_file(file);
2548 2549 2550 2551 2552
out:
	kfree(vol_args);
	return err;
}

C
Chris Mason 已提交
2553
static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
C
Christoph Hellwig 已提交
2554
{
A
Al Viro 已提交
2555
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
2556
	struct btrfs_root *root = BTRFS_I(inode)->root;
C
Chris Mason 已提交
2557
	struct btrfs_ioctl_defrag_range_args *range;
Y
Yan Zheng 已提交
2558 2559
	int ret;

2560 2561 2562
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
L
Li Zefan 已提交
2563

2564 2565 2566
	if (btrfs_root_readonly(root)) {
		ret = -EROFS;
		goto out;
2567
	}
C
Christoph Hellwig 已提交
2568 2569 2570

	switch (inode->i_mode & S_IFMT) {
	case S_IFDIR:
2571 2572 2573 2574
		if (!capable(CAP_SYS_ADMIN)) {
			ret = -EPERM;
			goto out;
		}
2575
		ret = btrfs_defrag_root(root);
2576 2577
		if (ret)
			goto out;
2578
		ret = btrfs_defrag_root(root->fs_info->extent_root);
C
Christoph Hellwig 已提交
2579 2580
		break;
	case S_IFREG:
2581 2582 2583 2584
		if (!(file->f_mode & FMODE_WRITE)) {
			ret = -EINVAL;
			goto out;
		}
C
Chris Mason 已提交
2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596

		range = kzalloc(sizeof(*range), GFP_KERNEL);
		if (!range) {
			ret = -ENOMEM;
			goto out;
		}

		if (argp) {
			if (copy_from_user(range, argp,
					   sizeof(*range))) {
				ret = -EFAULT;
				kfree(range);
2597
				goto out;
C
Chris Mason 已提交
2598 2599 2600 2601 2602 2603 2604 2605 2606 2607
			}
			/* 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;
		}
A
Al Viro 已提交
2608
		ret = btrfs_defrag_file(file_inode(file), file,
C
Chris Mason 已提交
2609 2610 2611
					range, 0, 0);
		if (ret > 0)
			ret = 0;
C
Chris Mason 已提交
2612
		kfree(range);
C
Christoph Hellwig 已提交
2613
		break;
2614 2615
	default:
		ret = -EINVAL;
C
Christoph Hellwig 已提交
2616
	}
2617
out:
2618
	mnt_drop_write_file(file);
2619
	return ret;
C
Christoph Hellwig 已提交
2620 2621
}

2622
static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
2623 2624 2625 2626
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

2627 2628 2629
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2630 2631
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
2632
		return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2633 2634
	}

2635
	mutex_lock(&root->fs_info->volume_mutex);
L
Li Zefan 已提交
2636
	vol_args = memdup_user(arg, sizeof(*vol_args));
2637 2638 2639 2640
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
C
Christoph Hellwig 已提交
2641

2642
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
2643 2644
	ret = btrfs_init_new_device(root, vol_args->name);

A
Anand Jain 已提交
2645 2646 2647
	if (!ret)
		btrfs_info(root->fs_info, "disk added %s",vol_args->name);

C
Christoph Hellwig 已提交
2648
	kfree(vol_args);
2649 2650
out:
	mutex_unlock(&root->fs_info->volume_mutex);
2651
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
C
Christoph Hellwig 已提交
2652 2653 2654
	return ret;
}

2655
static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
C
Christoph Hellwig 已提交
2656
{
A
Al Viro 已提交
2657
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
C
Christoph Hellwig 已提交
2658 2659 2660
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

2661 2662 2663
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2664 2665 2666
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
Y
Yan Zheng 已提交
2667

L
Li Zefan 已提交
2668
	vol_args = memdup_user(arg, sizeof(*vol_args));
2669 2670
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
D
Dan Carpenter 已提交
2671
		goto err_drop;
2672
	}
C
Christoph Hellwig 已提交
2673

2674
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
2675

2676 2677 2678 2679 2680 2681 2682 2683
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
		goto out;
	}

	mutex_lock(&root->fs_info->volume_mutex);
	ret = btrfs_rm_device(root, vol_args->name);
2684
	mutex_unlock(&root->fs_info->volume_mutex);
2685
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2686

2687 2688 2689
	if (!ret)
		btrfs_info(root->fs_info, "disk deleted %s",vol_args->name);

2690 2691
out:
	kfree(vol_args);
D
Dan Carpenter 已提交
2692
err_drop:
2693
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
2694 2695 2696
	return ret;
}

J
Jan Schmidt 已提交
2697 2698
static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
{
2699
	struct btrfs_ioctl_fs_info_args *fi_args;
J
Jan Schmidt 已提交
2700 2701 2702
	struct btrfs_device *device;
	struct btrfs_device *next;
	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2703
	int ret = 0;
J
Jan Schmidt 已提交
2704

2705 2706 2707 2708
	fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
	if (!fi_args)
		return -ENOMEM;

2709
	mutex_lock(&fs_devices->device_list_mutex);
2710 2711
	fi_args->num_devices = fs_devices->num_devices;
	memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
J
Jan Schmidt 已提交
2712 2713

	list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2714 2715
		if (device->devid > fi_args->max_id)
			fi_args->max_id = device->devid;
J
Jan Schmidt 已提交
2716 2717 2718
	}
	mutex_unlock(&fs_devices->device_list_mutex);

2719 2720 2721 2722
	fi_args->nodesize = root->fs_info->super_copy->nodesize;
	fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
	fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;

2723 2724
	if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
		ret = -EFAULT;
J
Jan Schmidt 已提交
2725

2726 2727
	kfree(fi_args);
	return ret;
J
Jan Schmidt 已提交
2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741
}

static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
{
	struct btrfs_ioctl_dev_info_args *di_args;
	struct btrfs_device *dev;
	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
	int ret = 0;
	char *s_uuid = NULL;

	di_args = memdup_user(arg, sizeof(*di_args));
	if (IS_ERR(di_args))
		return PTR_ERR(di_args);

2742
	if (!btrfs_is_empty_uuid(di_args->uuid))
J
Jan Schmidt 已提交
2743 2744 2745
		s_uuid = di_args->uuid;

	mutex_lock(&fs_devices->device_list_mutex);
2746
	dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
J
Jan Schmidt 已提交
2747 2748 2749 2750 2751 2752 2753

	if (!dev) {
		ret = -ENODEV;
		goto out;
	}

	di_args->devid = dev->devid;
2754 2755
	di_args->bytes_used = btrfs_device_get_bytes_used(dev);
	di_args->total_bytes = btrfs_device_get_total_bytes(dev);
J
Jan Schmidt 已提交
2756
	memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2757
	if (dev->name) {
2758 2759 2760 2761 2762 2763
		struct rcu_string *name;

		rcu_read_lock();
		name = rcu_dereference(dev->name);
		strncpy(di_args->path, name->str, sizeof(di_args->path));
		rcu_read_unlock();
2764 2765
		di_args->path[sizeof(di_args->path) - 1] = 0;
	} else {
2766
		di_args->path[0] = '\0';
2767
	}
J
Jan Schmidt 已提交
2768 2769

out:
2770
	mutex_unlock(&fs_devices->device_list_mutex);
J
Jan Schmidt 已提交
2771 2772 2773 2774 2775 2776 2777
	if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
		ret = -EFAULT;

	kfree(di_args);
	return ret;
}

M
Mark Fasheh 已提交
2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805
static struct page *extent_same_get_page(struct inode *inode, u64 off)
{
	struct page *page;
	pgoff_t index;
	struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;

	index = off >> PAGE_CACHE_SHIFT;

	page = grab_cache_page(inode->i_mapping, index);
	if (!page)
		return NULL;

	if (!PageUptodate(page)) {
		if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
						 0))
			return NULL;
		lock_page(page);
		if (!PageUptodate(page)) {
			unlock_page(page);
			page_cache_release(page);
			return NULL;
		}
	}
	unlock_page(page);

	return page;
}

2806 2807 2808 2809 2810 2811 2812 2813 2814
static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
{
	/* do any pending delalloc/csum calc on src, one way or
	   another, and lock file content */
	while (1) {
		struct btrfs_ordered_extent *ordered;
		lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
		ordered = btrfs_lookup_first_ordered_extent(inode,
							    off + len - 1);
2815 2816 2817
		if ((!ordered ||
		     ordered->file_offset + ordered->len <= off ||
		     ordered->file_offset >= off + len) &&
2818
		    !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2819 2820 2821
				    off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
			if (ordered)
				btrfs_put_ordered_extent(ordered);
2822
			break;
2823
		}
2824 2825 2826 2827 2828 2829 2830
		unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
		if (ordered)
			btrfs_put_ordered_extent(ordered);
		btrfs_wait_ordered_range(inode, off, len);
	}
}

M
Mark Fasheh 已提交
2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957
static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
				struct inode *inode2, u64 loff2, u64 len)
{
	unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
	unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);

	mutex_unlock(&inode1->i_mutex);
	mutex_unlock(&inode2->i_mutex);
}

static void btrfs_double_lock(struct inode *inode1, u64 loff1,
			      struct inode *inode2, u64 loff2, u64 len)
{
	if (inode1 < inode2) {
		swap(inode1, inode2);
		swap(loff1, loff2);
	}

	mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
	lock_extent_range(inode1, loff1, len);
	if (inode1 != inode2) {
		mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
		lock_extent_range(inode2, loff2, len);
	}
}

static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
			  u64 dst_loff, u64 len)
{
	int ret = 0;
	struct page *src_page, *dst_page;
	unsigned int cmp_len = PAGE_CACHE_SIZE;
	void *addr, *dst_addr;

	while (len) {
		if (len < PAGE_CACHE_SIZE)
			cmp_len = len;

		src_page = extent_same_get_page(src, loff);
		if (!src_page)
			return -EINVAL;
		dst_page = extent_same_get_page(dst, dst_loff);
		if (!dst_page) {
			page_cache_release(src_page);
			return -EINVAL;
		}
		addr = kmap_atomic(src_page);
		dst_addr = kmap_atomic(dst_page);

		flush_dcache_page(src_page);
		flush_dcache_page(dst_page);

		if (memcmp(addr, dst_addr, cmp_len))
			ret = BTRFS_SAME_DATA_DIFFERS;

		kunmap_atomic(addr);
		kunmap_atomic(dst_addr);
		page_cache_release(src_page);
		page_cache_release(dst_page);

		if (ret)
			break;

		loff += cmp_len;
		dst_loff += cmp_len;
		len -= cmp_len;
	}

	return ret;
}

static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
{
	u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;

	if (off + len > inode->i_size || off + len < off)
		return -EINVAL;
	/* Check that we are block aligned - btrfs_clone() requires this */
	if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
		return -EINVAL;

	return 0;
}

static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
			     struct inode *dst, u64 dst_loff)
{
	int ret;

	/*
	 * btrfs_clone() can't handle extents in the same file
	 * yet. Once that works, we can drop this check and replace it
	 * with a check for the same inode, but overlapping extents.
	 */
	if (src == dst)
		return -EINVAL;

	btrfs_double_lock(src, loff, dst, dst_loff, len);

	ret = extent_same_check_offsets(src, loff, len);
	if (ret)
		goto out_unlock;

	ret = extent_same_check_offsets(dst, dst_loff, len);
	if (ret)
		goto out_unlock;

	/* don't make the dst file partly checksummed */
	if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
	    (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
		ret = -EINVAL;
		goto out_unlock;
	}

	ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
	if (ret == 0)
		ret = btrfs_clone(src, dst, loff, len, len, dst_loff);

out_unlock:
	btrfs_double_unlock(src, loff, dst, dst_loff, len);

	return ret;
}

#define BTRFS_MAX_DEDUPE_LEN	(16 * 1024 * 1024)

static long btrfs_ioctl_file_extent_same(struct file *file,
2958
			struct btrfs_ioctl_same_args __user *argp)
M
Mark Fasheh 已提交
2959
{
2960 2961
	struct btrfs_ioctl_same_args *same;
	struct btrfs_ioctl_same_extent_info *info;
2962
	struct inode *src = file_inode(file);
M
Mark Fasheh 已提交
2963 2964 2965 2966
	u64 off;
	u64 len;
	int i;
	int ret;
2967
	unsigned long size;
M
Mark Fasheh 已提交
2968 2969
	u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
	bool is_admin = capable(CAP_SYS_ADMIN);
2970
	u16 count;
M
Mark Fasheh 已提交
2971 2972 2973 2974 2975 2976 2977 2978

	if (!(file->f_mode & FMODE_READ))
		return -EINVAL;

	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

2979
	if (get_user(count, &argp->dest_count)) {
M
Mark Fasheh 已提交
2980 2981 2982 2983
		ret = -EFAULT;
		goto out;
	}

2984
	size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2985

2986
	same = memdup_user(argp, size);
2987

2988 2989
	if (IS_ERR(same)) {
		ret = PTR_ERR(same);
2990 2991 2992 2993 2994
		goto out;
	}

	off = same->logical_offset;
	len = same->length;
M
Mark Fasheh 已提交
2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021

	/*
	 * Limit the total length we will dedupe for each operation.
	 * This is intended to bound the total time spent in this
	 * ioctl to something sane.
	 */
	if (len > BTRFS_MAX_DEDUPE_LEN)
		len = BTRFS_MAX_DEDUPE_LEN;

	if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
		/*
		 * Btrfs does not support blocksize < page_size. As a
		 * result, btrfs_cmp_data() won't correctly handle
		 * this situation without an update.
		 */
		ret = -EINVAL;
		goto out;
	}

	ret = -EISDIR;
	if (S_ISDIR(src->i_mode))
		goto out;

	ret = -EACCES;
	if (!S_ISREG(src->i_mode))
		goto out;

3022
	/* pre-format output fields to sane values */
3023
	for (i = 0; i < count; i++) {
3024 3025 3026
		same->info[i].bytes_deduped = 0ULL;
		same->info[i].status = 0;
	}
M
Mark Fasheh 已提交
3027

3028 3029 3030 3031
	for (i = 0, info = same->info; i < count; i++, info++) {
		struct inode *dst;
		struct fd dst_file = fdget(info->fd);
		if (!dst_file.file) {
3032
			info->status = -EBADF;
3033
			continue;
M
Mark Fasheh 已提交
3034
		}
3035
		dst = file_inode(dst_file.file);
M
Mark Fasheh 已提交
3036

3037
		if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3038
			info->status = -EINVAL;
3039 3040 3041
		} else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
			info->status = -EXDEV;
		} else if (S_ISDIR(dst->i_mode)) {
3042
			info->status = -EISDIR;
3043
		} else if (!S_ISREG(dst->i_mode)) {
3044
			info->status = -EACCES;
3045 3046 3047 3048 3049
		} else {
			info->status = btrfs_extent_same(src, off, len, dst,
							info->logical_offset);
			if (info->status == 0)
				info->bytes_deduped += len;
M
Mark Fasheh 已提交
3050
		}
3051
		fdput(dst_file);
M
Mark Fasheh 已提交
3052 3053
	}

3054 3055 3056 3057
	ret = copy_to_user(argp, same, size);
	if (ret)
		ret = -EFAULT;

M
Mark Fasheh 已提交
3058 3059 3060 3061 3062
out:
	mnt_drop_write_file(file);
	return ret;
}

J
Josef Bacik 已提交
3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097
/* Helper to check and see if this root currently has a ref on the given disk
 * bytenr.  If it does then we need to update the quota for this root.  This
 * doesn't do anything if quotas aren't enabled.
 */
static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
		     u64 disko)
{
	struct seq_list tree_mod_seq_elem = {};
	struct ulist *roots;
	struct ulist_iterator uiter;
	struct ulist_node *root_node = NULL;
	int ret;

	if (!root->fs_info->quota_enabled)
		return 1;

	btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
	ret = btrfs_find_all_roots(trans, root->fs_info, disko,
				   tree_mod_seq_elem.seq, &roots);
	if (ret < 0)
		goto out;
	ret = 0;
	ULIST_ITER_INIT(&uiter);
	while ((root_node = ulist_next(roots, &uiter))) {
		if (root_node->val == root->objectid) {
			ret = 1;
			break;
		}
	}
	ulist_free(roots);
out:
	btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
	return ret;
}

3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128
static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
				     struct inode *inode,
				     u64 endoff,
				     const u64 destoff,
				     const u64 olen)
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret;

	inode_inc_iversion(inode);
	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	/*
	 * We round up to the block size at eof when determining which
	 * extents to clone above, but shouldn't round up the file size.
	 */
	if (endoff > destoff + olen)
		endoff = destoff + olen;
	if (endoff > inode->i_size)
		btrfs_i_size_write(inode, endoff);

	ret = btrfs_update_inode(trans, root, inode);
	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
		btrfs_end_transaction(trans, root);
		goto out;
	}
	ret = btrfs_end_transaction(trans, root);
out:
	return ret;
}

3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145
static void clone_update_extent_map(struct inode *inode,
				    const struct btrfs_trans_handle *trans,
				    const struct btrfs_path *path,
				    const u64 hole_offset,
				    const u64 hole_len)
{
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
	struct extent_map *em;
	int ret;

	em = alloc_extent_map();
	if (!em) {
		set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
			&BTRFS_I(inode)->runtime_flags);
		return;
	}

3146 3147 3148 3149 3150
	if (path) {
		struct btrfs_file_extent_item *fi;

		fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
				    struct btrfs_file_extent_item);
3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180
		btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
		em->generation = -1;
		if (btrfs_file_extent_type(path->nodes[0], fi) ==
		    BTRFS_FILE_EXTENT_INLINE)
			set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
				&BTRFS_I(inode)->runtime_flags);
	} else {
		em->start = hole_offset;
		em->len = hole_len;
		em->ram_bytes = em->len;
		em->orig_start = hole_offset;
		em->block_start = EXTENT_MAP_HOLE;
		em->block_len = 0;
		em->orig_block_len = 0;
		em->compress_type = BTRFS_COMPRESS_NONE;
		em->generation = trans->transid;
	}

	while (1) {
		write_lock(&em_tree->lock);
		ret = add_extent_mapping(em_tree, em, 1);
		write_unlock(&em_tree->lock);
		if (ret != -EEXIST) {
			free_extent_map(em);
			break;
		}
		btrfs_drop_extent_cache(inode, em->start,
					em->start + em->len - 1, 0);
	}

3181
	if (ret)
3182 3183 3184 3185
		set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
			&BTRFS_I(inode)->runtime_flags);
}

3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197
/**
 * btrfs_clone() - clone a range from inode file to another
 *
 * @src: Inode to clone from
 * @inode: Inode to clone to
 * @off: Offset within source to start clone from
 * @olen: Original length, passed by user, of range to clone
 * @olen_aligned: Block-aligned value of olen, extent_same uses
 *               identical values here
 * @destoff: Offset within @inode to start clone
 */
static int btrfs_clone(struct inode *src, struct inode *inode,
3198 3199
		       const u64 off, const u64 olen, const u64 olen_aligned,
		       const u64 destoff)
C
Christoph Hellwig 已提交
3200 3201
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
3202
	struct btrfs_path *path = NULL;
C
Christoph Hellwig 已提交
3203
	struct extent_buffer *leaf;
3204 3205
	struct btrfs_trans_handle *trans;
	char *buf = NULL;
Y
Yan Zheng 已提交
3206
	struct btrfs_key key;
C
Christoph Hellwig 已提交
3207 3208
	u32 nritems;
	int slot;
Y
Yan Zheng 已提交
3209
	int ret;
J
Josef Bacik 已提交
3210
	int no_quota;
3211
	const u64 len = olen_aligned;
J
Josef Bacik 已提交
3212
	u64 last_disko = 0;
3213
	u64 last_dest_end = destoff;
Y
Yan Zheng 已提交
3214 3215

	ret = -ENOMEM;
3216
	buf = vmalloc(root->nodesize);
Y
Yan Zheng 已提交
3217
	if (!buf)
3218
		return ret;
Y
Yan Zheng 已提交
3219 3220 3221 3222

	path = btrfs_alloc_path();
	if (!path) {
		vfree(buf);
3223
		return ret;
3224 3225
	}

3226
	path->reada = 2;
3227
	/* clone data */
L
Li Zefan 已提交
3228
	key.objectid = btrfs_ino(src);
Y
Yan Zheng 已提交
3229
	key.type = BTRFS_EXTENT_DATA_KEY;
3230
	key.offset = off;
C
Christoph Hellwig 已提交
3231 3232 3233 3234 3235 3236

	while (1) {
		/*
		 * note the key will change type as we walk through the
		 * tree.
		 */
3237
		path->leave_spinning = 1;
3238 3239
		ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
				0, 0);
C
Christoph Hellwig 已提交
3240 3241
		if (ret < 0)
			goto out;
3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252
		/*
		 * First search, if no extent item that starts at offset off was
		 * found but the previous item is an extent item, it's possible
		 * it might overlap our target range, therefore process it.
		 */
		if (key.offset == off && ret > 0 && path->slots[0] > 0) {
			btrfs_item_key_to_cpu(path->nodes[0], &key,
					      path->slots[0] - 1);
			if (key.type == BTRFS_EXTENT_DATA_KEY)
				path->slots[0]--;
		}
C
Christoph Hellwig 已提交
3253

Y
Yan Zheng 已提交
3254
		nritems = btrfs_header_nritems(path->nodes[0]);
3255
process_slot:
J
Josef Bacik 已提交
3256
		no_quota = 1;
Y
Yan Zheng 已提交
3257
		if (path->slots[0] >= nritems) {
3258
			ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
C
Christoph Hellwig 已提交
3259 3260 3261 3262
			if (ret < 0)
				goto out;
			if (ret > 0)
				break;
Y
Yan Zheng 已提交
3263
			nritems = btrfs_header_nritems(path->nodes[0]);
C
Christoph Hellwig 已提交
3264 3265 3266 3267
		}
		leaf = path->nodes[0];
		slot = path->slots[0];

Y
Yan Zheng 已提交
3268
		btrfs_item_key_to_cpu(leaf, &key, slot);
3269
		if (key.type > BTRFS_EXTENT_DATA_KEY ||
L
Li Zefan 已提交
3270
		    key.objectid != btrfs_ino(src))
C
Christoph Hellwig 已提交
3271 3272
			break;

3273
		if (key.type == BTRFS_EXTENT_DATA_KEY) {
3274 3275
			struct btrfs_file_extent_item *extent;
			int type;
Z
Zheng Yan 已提交
3276 3277
			u32 size;
			struct btrfs_key new_key;
3278 3279 3280
			u64 disko = 0, diskl = 0;
			u64 datao = 0, datal = 0;
			u8 comp;
3281
			u64 drop_start;
Z
Zheng Yan 已提交
3282

3283 3284 3285 3286
			extent = btrfs_item_ptr(leaf, slot,
						struct btrfs_file_extent_item);
			comp = btrfs_file_extent_compression(leaf, extent);
			type = btrfs_file_extent_type(leaf, extent);
3287 3288
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
C
Chris Mason 已提交
3289 3290 3291 3292
				disko = btrfs_file_extent_disk_bytenr(leaf,
								      extent);
				diskl = btrfs_file_extent_disk_num_bytes(leaf,
								 extent);
3293
				datao = btrfs_file_extent_offset(leaf, extent);
C
Chris Mason 已提交
3294 3295
				datal = btrfs_file_extent_num_bytes(leaf,
								    extent);
3296 3297 3298 3299 3300
			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
				/* take upper bound, may be compressed */
				datal = btrfs_file_extent_ram_bytes(leaf,
								    extent);
			}
Z
Zheng Yan 已提交
3301

3302 3303 3304 3305 3306 3307
			/*
			 * The first search might have left us at an extent
			 * item that ends before our target range's start, can
			 * happen if we have holes and NO_HOLES feature enabled.
			 */
			if (key.offset + datal <= off) {
3308 3309
				path->slots[0]++;
				goto process_slot;
3310 3311
			} else if (key.offset >= off + len) {
				break;
3312 3313 3314 3315 3316 3317 3318 3319 3320
			}

			size = btrfs_item_size_nr(leaf, slot);
			read_extent_buffer(leaf, buf,
					   btrfs_item_ptr_offset(leaf, slot),
					   size);

			btrfs_release_path(path);
			path->leave_spinning = 0;
3321

Z
Zheng Yan 已提交
3322
			memcpy(&new_key, &key, sizeof(new_key));
L
Li Zefan 已提交
3323
			new_key.objectid = btrfs_ino(inode);
3324 3325 3326 3327
			if (off <= key.offset)
				new_key.offset = key.offset + destoff - off;
			else
				new_key.offset = destoff;
Z
Zheng Yan 已提交
3328

3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340
			/*
			 * Deal with a hole that doesn't have an extent item
			 * that represents it (NO_HOLES feature enabled).
			 * This hole is either in the middle of the cloning
			 * range or at the beginning (fully overlaps it or
			 * partially overlaps it).
			 */
			if (new_key.offset != last_dest_end)
				drop_start = last_dest_end;
			else
				drop_start = new_key.offset;

3341 3342 3343 3344 3345 3346
			/*
			 * 1 - adjusting old extent (we may have to split it)
			 * 1 - add new extent
			 * 1 - inode update
			 */
			trans = btrfs_start_transaction(root, 3);
3347 3348 3349 3350 3351
			if (IS_ERR(trans)) {
				ret = PTR_ERR(trans);
				goto out;
			}

3352 3353
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
3354 3355 3356 3357 3358
				/*
				 *    a  | --- range to clone ---|  b
				 * | ------------- extent ------------- |
				 */

3359
				/* subtract range b */
3360 3361 3362
				if (key.offset + datal > off + len)
					datal = off + len - key.offset;

3363
				/* subtract range a */
3364 3365 3366 3367 3368
				if (off > key.offset) {
					datao += off - key.offset;
					datal -= off - key.offset;
				}

J
Josef Bacik 已提交
3369
				ret = btrfs_drop_extents(trans, root, inode,
3370
							 drop_start,
3371
							 new_key.offset + datal,
3372
							 1);
3373
				if (ret) {
3374
					if (ret != -EOPNOTSUPP)
3375 3376
						btrfs_abort_transaction(trans,
								root, ret);
3377 3378 3379
					btrfs_end_transaction(trans, root);
					goto out;
				}
3380

3381 3382
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
3383 3384 3385 3386 3387 3388
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
3389 3390 3391 3392

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
Z
Zheng Yan 已提交
3393 3394
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
Y
Yan Zheng 已提交
3395

3396
				extent = btrfs_item_ptr(leaf, slot,
C
Christoph Hellwig 已提交
3397
						struct btrfs_file_extent_item);
3398 3399 3400 3401 3402 3403 3404 3405 3406

				/* disko == 0 means it's a hole */
				if (!disko)
					datao = 0;

				btrfs_set_file_extent_offset(leaf, extent,
							     datao);
				btrfs_set_file_extent_num_bytes(leaf, extent,
								datal);
J
Josef Bacik 已提交
3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428

				/*
				 * We need to look up the roots that point at
				 * this bytenr and see if the new root does.  If
				 * it does not we need to make sure we update
				 * quotas appropriately.
				 */
				if (disko && root != BTRFS_I(src)->root &&
				    disko != last_disko) {
					no_quota = check_ref(trans, root,
							     disko);
					if (no_quota < 0) {
						btrfs_abort_transaction(trans,
									root,
									ret);
						btrfs_end_transaction(trans,
								      root);
						ret = no_quota;
						goto out;
					}
				}

3429 3430
				if (disko) {
					inode_add_bytes(inode, datal);
Y
Yan Zheng 已提交
3431
					ret = btrfs_inc_extent_ref(trans, root,
3432 3433
							disko, diskl, 0,
							root->root_key.objectid,
L
Li Zefan 已提交
3434
							btrfs_ino(inode),
A
Arne Jansen 已提交
3435
							new_key.offset - datao,
J
Josef Bacik 已提交
3436
							no_quota);
3437 3438 3439 3440 3441 3442 3443 3444 3445
					if (ret) {
						btrfs_abort_transaction(trans,
									root,
									ret);
						btrfs_end_transaction(trans,
								      root);
						goto out;

					}
C
Christoph Hellwig 已提交
3446
				}
3447 3448 3449
			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
				u64 skip = 0;
				u64 trim = 0;
3450 3451
				u64 aligned_end = 0;

3452 3453 3454 3455
				if (off > key.offset) {
					skip = off - key.offset;
					new_key.offset += skip;
				}
C
Chris Mason 已提交
3456

L
Liu Bo 已提交
3457 3458
				if (key.offset + datal > off + len)
					trim = key.offset + datal - (off + len);
C
Chris Mason 已提交
3459

3460 3461
				if (comp && (skip || trim)) {
					ret = -EINVAL;
3462
					btrfs_end_transaction(trans, root);
3463 3464 3465 3466
					goto out;
				}
				size -= skip + trim;
				datal -= skip + trim;
3467

3468 3469
				aligned_end = ALIGN(new_key.offset + datal,
						    root->sectorsize);
J
Josef Bacik 已提交
3470
				ret = btrfs_drop_extents(trans, root, inode,
3471
							 drop_start,
3472
							 aligned_end,
3473
							 1);
3474
				if (ret) {
3475
					if (ret != -EOPNOTSUPP)
3476 3477
						btrfs_abort_transaction(trans,
							root, ret);
3478 3479 3480
					btrfs_end_transaction(trans, root);
					goto out;
				}
3481

3482 3483
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
3484 3485 3486 3487 3488 3489
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
3490 3491

				if (skip) {
C
Chris Mason 已提交
3492 3493
					u32 start =
					  btrfs_file_extent_calc_inline_size(0);
3494 3495 3496 3497 3498 3499 3500 3501 3502 3503
					memmove(buf+start, buf+start+skip,
						datal);
				}

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
				inode_add_bytes(inode, datal);
C
Christoph Hellwig 已提交
3504
			}
3505

3506 3507 3508
			/* If we have an implicit hole (NO_HOLES feature). */
			if (drop_start < new_key.offset)
				clone_update_extent_map(inode, trans,
3509
						NULL, drop_start,
3510 3511
						new_key.offset - drop_start);

3512
			clone_update_extent_map(inode, trans, path, 0, 0);
3513

3514
			btrfs_mark_buffer_dirty(leaf);
3515
			btrfs_release_path(path);
3516

3517 3518
			last_dest_end = ALIGN(new_key.offset + datal,
					      root->sectorsize);
3519 3520 3521 3522
			ret = clone_finish_inode_update(trans, inode,
							last_dest_end,
							destoff, olen);
			if (ret)
3523
				goto out;
3524 3525
			if (new_key.offset + datal >= destoff + len)
				break;
3526
		}
3527
		btrfs_release_path(path);
C
Christoph Hellwig 已提交
3528 3529 3530
		key.offset++;
	}
	ret = 0;
3531

3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555
	if (last_dest_end < destoff + len) {
		/*
		 * We have an implicit hole (NO_HOLES feature is enabled) that
		 * fully or partially overlaps our cloning range at its end.
		 */
		btrfs_release_path(path);

		/*
		 * 1 - remove extent(s)
		 * 1 - inode update
		 */
		trans = btrfs_start_transaction(root, 2);
		if (IS_ERR(trans)) {
			ret = PTR_ERR(trans);
			goto out;
		}
		ret = btrfs_drop_extents(trans, root, inode,
					 last_dest_end, destoff + len, 1);
		if (ret) {
			if (ret != -EOPNOTSUPP)
				btrfs_abort_transaction(trans, root, ret);
			btrfs_end_transaction(trans, root);
			goto out;
		}
3556 3557
		clone_update_extent_map(inode, trans, NULL, last_dest_end,
					destoff + len - last_dest_end);
3558 3559 3560 3561
		ret = clone_finish_inode_update(trans, inode, destoff + len,
						destoff, olen);
	}

C
Christoph Hellwig 已提交
3562
out:
3563 3564 3565 3566 3567 3568 3569 3570
	btrfs_free_path(path);
	vfree(buf);
	return ret;
}

static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
				       u64 off, u64 olen, u64 destoff)
{
A
Al Viro 已提交
3571
	struct inode *inode = file_inode(file);
3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct fd src_file;
	struct inode *src;
	int ret;
	u64 len = olen;
	u64 bs = root->fs_info->sb->s_blocksize;
	int same_inode = 0;

	/*
	 * TODO:
	 * - split compressed inline extents.  annoying: we need to
	 *   decompress into destination's address_space (the file offset
	 *   may change, so source mapping won't do), then recompress (or
	 *   otherwise reinsert) a subrange.
3586 3587 3588
	 *
	 * - split destination inode's inline extents.  The inline extents can
	 *   be either compressed or non-compressed.
3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673
	 */

	/* the destination must be opened for writing */
	if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
		return -EINVAL;

	if (btrfs_root_readonly(root))
		return -EROFS;

	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	src_file = fdget(srcfd);
	if (!src_file.file) {
		ret = -EBADF;
		goto out_drop_write;
	}

	ret = -EXDEV;
	if (src_file.file->f_path.mnt != file->f_path.mnt)
		goto out_fput;

	src = file_inode(src_file.file);

	ret = -EINVAL;
	if (src == inode)
		same_inode = 1;

	/* the src must be open for reading */
	if (!(src_file.file->f_mode & FMODE_READ))
		goto out_fput;

	/* don't make the dst file partly checksummed */
	if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
	    (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
		goto out_fput;

	ret = -EISDIR;
	if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
		goto out_fput;

	ret = -EXDEV;
	if (src->i_sb != inode->i_sb)
		goto out_fput;

	if (!same_inode) {
		if (inode < src) {
			mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
			mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
		} else {
			mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
			mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
		}
	} else {
		mutex_lock(&src->i_mutex);
	}

	/* determine range to clone */
	ret = -EINVAL;
	if (off + len > src->i_size || off + len < off)
		goto out_unlock;
	if (len == 0)
		olen = len = src->i_size - off;
	/* if we extend to eof, continue to block boundary */
	if (off + len == src->i_size)
		len = ALIGN(src->i_size, bs) - off;

	/* verify the end result is block aligned */
	if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
	    !IS_ALIGNED(destoff, bs))
		goto out_unlock;

	/* verify if ranges are overlapped within the same file */
	if (same_inode) {
		if (destoff + len > off && destoff < off + len)
			goto out_unlock;
	}

	if (destoff > inode->i_size) {
		ret = btrfs_cont_expand(inode, inode->i_size, destoff);
		if (ret)
			goto out_unlock;
	}

3674 3675 3676 3677 3678 3679 3680 3681 3682 3683
	/*
	 * Lock the target range too. Right after we replace the file extent
	 * items in the fs tree (which now point to the cloned data), we might
	 * have a worker replace them with extent items relative to a write
	 * operation that was issued before this clone operation (i.e. confront
	 * with inode.c:btrfs_finish_ordered_io).
	 */
	if (same_inode) {
		u64 lock_start = min_t(u64, off, destoff);
		u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3684

3685 3686 3687 3688 3689
		lock_extent_range(src, lock_start, lock_len);
	} else {
		lock_extent_range(src, off, len);
		lock_extent_range(inode, destoff, len);
	}
3690 3691 3692

	ret = btrfs_clone(src, inode, off, olen, len, destoff);

3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708
	if (same_inode) {
		u64 lock_start = min_t(u64, off, destoff);
		u64 lock_end = max_t(u64, off, destoff) + len - 1;

		unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
	} else {
		unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
		unlock_extent(&BTRFS_I(inode)->io_tree, destoff,
			      destoff + len - 1);
	}
	/*
	 * Truncate page cache pages so that future reads will see the cloned
	 * data immediately and not the previous data.
	 */
	truncate_inode_pages_range(&inode->i_data, destoff,
				   PAGE_CACHE_ALIGN(destoff + len) - 1);
C
Christoph Hellwig 已提交
3709
out_unlock:
3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720
	if (!same_inode) {
		if (inode < src) {
			mutex_unlock(&src->i_mutex);
			mutex_unlock(&inode->i_mutex);
		} else {
			mutex_unlock(&inode->i_mutex);
			mutex_unlock(&src->i_mutex);
		}
	} else {
		mutex_unlock(&src->i_mutex);
	}
C
Christoph Hellwig 已提交
3721
out_fput:
3722
	fdput(src_file);
3723
out_drop_write:
A
Al Viro 已提交
3724
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
3725 3726 3727
	return ret;
}

3728
static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3729 3730 3731
{
	struct btrfs_ioctl_clone_range_args args;

3732
	if (copy_from_user(&args, argp, sizeof(args)))
3733 3734 3735 3736 3737
		return -EFAULT;
	return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
				 args.src_length, args.dest_offset);
}

C
Christoph Hellwig 已提交
3738 3739 3740 3741 3742 3743
/*
 * there are many ways the trans_start and trans_end ioctls can lead
 * to deadlocks.  They should only be used by applications that
 * basically own the machine, and have a very in depth understanding
 * of all the possible deadlocks and enospc problems.
 */
3744
static long btrfs_ioctl_trans_start(struct file *file)
C
Christoph Hellwig 已提交
3745
{
A
Al Viro 已提交
3746
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
3747 3748
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
3749
	int ret;
C
Christoph Hellwig 已提交
3750

3751
	ret = -EPERM;
3752
	if (!capable(CAP_SYS_ADMIN))
3753
		goto out;
3754

3755 3756
	ret = -EINPROGRESS;
	if (file->private_data)
C
Christoph Hellwig 已提交
3757
		goto out;
3758

L
Li Zefan 已提交
3759 3760 3761 3762
	ret = -EROFS;
	if (btrfs_root_readonly(root))
		goto out;

3763
	ret = mnt_want_write_file(file);
Y
Yan Zheng 已提交
3764 3765 3766
	if (ret)
		goto out;

J
Josef Bacik 已提交
3767
	atomic_inc(&root->fs_info->open_ioctl_trans);
3768

3769
	ret = -ENOMEM;
3770
	trans = btrfs_start_ioctl_transaction(root);
3771
	if (IS_ERR(trans))
3772 3773 3774 3775 3776 3777
		goto out_drop;

	file->private_data = trans;
	return 0;

out_drop:
J
Josef Bacik 已提交
3778
	atomic_dec(&root->fs_info->open_ioctl_trans);
A
Al Viro 已提交
3779
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
3780 3781 3782 3783
out:
	return ret;
}

3784 3785
static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
{
A
Al Viro 已提交
3786
	struct inode *inode = file_inode(file);
3787 3788 3789 3790 3791 3792 3793 3794 3795
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_root *new_root;
	struct btrfs_dir_item *di;
	struct btrfs_trans_handle *trans;
	struct btrfs_path *path;
	struct btrfs_key location;
	struct btrfs_disk_key disk_key;
	u64 objectid = 0;
	u64 dir_id;
3796
	int ret;
3797 3798 3799 3800

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

3801 3802 3803 3804 3805 3806 3807 3808
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	if (copy_from_user(&objectid, argp, sizeof(objectid))) {
		ret = -EFAULT;
		goto out;
	}
3809 3810

	if (!objectid)
3811
		objectid = BTRFS_FS_TREE_OBJECTID;
3812 3813 3814 3815 3816 3817

	location.objectid = objectid;
	location.type = BTRFS_ROOT_ITEM_KEY;
	location.offset = (u64)-1;

	new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3818 3819 3820 3821
	if (IS_ERR(new_root)) {
		ret = PTR_ERR(new_root);
		goto out;
	}
3822 3823

	path = btrfs_alloc_path();
3824 3825 3826 3827
	if (!path) {
		ret = -ENOMEM;
		goto out;
	}
3828 3829 3830
	path->leave_spinning = 1;

	trans = btrfs_start_transaction(root, 1);
3831
	if (IS_ERR(trans)) {
3832
		btrfs_free_path(path);
3833 3834
		ret = PTR_ERR(trans);
		goto out;
3835 3836
	}

3837
	dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3838 3839
	di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
				   dir_id, "default", 7, 1);
3840
	if (IS_ERR_OR_NULL(di)) {
3841 3842
		btrfs_free_path(path);
		btrfs_end_transaction(trans, root);
3843 3844
		btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
			   "item, this isn't going to work");
3845 3846
		ret = -ENOENT;
		goto out;
3847 3848 3849 3850 3851 3852 3853
	}

	btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
	btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
	btrfs_mark_buffer_dirty(path->nodes[0]);
	btrfs_free_path(path);

3854
	btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3855
	btrfs_end_transaction(trans, root);
3856 3857 3858
out:
	mnt_drop_write_file(file);
	return ret;
3859 3860
}

3861 3862
void btrfs_get_block_group_info(struct list_head *groups_list,
				struct btrfs_ioctl_space_info *space)
3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873 3874 3875 3876
{
	struct btrfs_block_group_cache *block_group;

	space->total_bytes = 0;
	space->used_bytes = 0;
	space->flags = 0;
	list_for_each_entry(block_group, groups_list, list) {
		space->flags = block_group->flags;
		space->total_bytes += block_group->key.offset;
		space->used_bytes +=
			btrfs_block_group_used(&block_group->item);
	}
}

3877
static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
J
Josef Bacik 已提交
3878 3879 3880 3881
{
	struct btrfs_ioctl_space_args space_args;
	struct btrfs_ioctl_space_info space;
	struct btrfs_ioctl_space_info *dest;
3882
	struct btrfs_ioctl_space_info *dest_orig;
3883
	struct btrfs_ioctl_space_info __user *user_dest;
J
Josef Bacik 已提交
3884
	struct btrfs_space_info *info;
3885 3886 3887 3888 3889
	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;
3890
	int alloc_size;
J
Josef Bacik 已提交
3891
	int ret = 0;
3892
	u64 slot_count = 0;
3893
	int i, c;
J
Josef Bacik 已提交
3894 3895 3896 3897 3898 3899

	if (copy_from_user(&space_args,
			   (struct btrfs_ioctl_space_args __user *)arg,
			   sizeof(space_args)))
		return -EFAULT;

3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923
	for (i = 0; i < num_types; i++) {
		struct btrfs_space_info *tmp;

		info = NULL;
		rcu_read_lock();
		list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
					list) {
			if (tmp->flags == types[i]) {
				info = tmp;
				break;
			}
		}
		rcu_read_unlock();

		if (!info)
			continue;

		down_read(&info->groups_sem);
		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
			if (!list_empty(&info->block_groups[c]))
				slot_count++;
		}
		up_read(&info->groups_sem);
	}
3924

3925 3926 3927 3928 3929
	/*
	 * Global block reserve, exported as a space_info
	 */
	slot_count++;

3930 3931 3932 3933 3934
	/* space_slots == 0 means they are asking for a count */
	if (space_args.space_slots == 0) {
		space_args.total_spaces = slot_count;
		goto out;
	}
3935

3936
	slot_count = min_t(u64, space_args.space_slots, slot_count);
3937

3938
	alloc_size = sizeof(*dest) * slot_count;
3939

3940 3941 3942 3943 3944 3945
	/* we generally have at most 6 or so space infos, one for each raid
	 * level.  So, a whole page should be more than enough for everyone
	 */
	if (alloc_size > PAGE_CACHE_SIZE)
		return -ENOMEM;

J
Josef Bacik 已提交
3946
	space_args.total_spaces = 0;
3947 3948 3949 3950
	dest = kmalloc(alloc_size, GFP_NOFS);
	if (!dest)
		return -ENOMEM;
	dest_orig = dest;
J
Josef Bacik 已提交
3951

3952
	/* now we have a buffer to copy into */
3953 3954 3955
	for (i = 0; i < num_types; i++) {
		struct btrfs_space_info *tmp;

3956 3957 3958
		if (!slot_count)
			break;

3959 3960 3961 3962 3963 3964 3965 3966 3967 3968
		info = NULL;
		rcu_read_lock();
		list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
					list) {
			if (tmp->flags == types[i]) {
				info = tmp;
				break;
			}
		}
		rcu_read_unlock();
3969

3970 3971 3972 3973 3974
		if (!info)
			continue;
		down_read(&info->groups_sem);
		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
			if (!list_empty(&info->block_groups[c])) {
3975 3976
				btrfs_get_block_group_info(
					&info->block_groups[c], &space);
3977 3978 3979
				memcpy(dest, &space, sizeof(space));
				dest++;
				space_args.total_spaces++;
3980
				slot_count--;
3981
			}
3982 3983
			if (!slot_count)
				break;
3984 3985
		}
		up_read(&info->groups_sem);
J
Josef Bacik 已提交
3986 3987
	}

3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 4002
	/*
	 * Add global block reserve
	 */
	if (slot_count) {
		struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;

		spin_lock(&block_rsv->lock);
		space.total_bytes = block_rsv->size;
		space.used_bytes = block_rsv->size - block_rsv->reserved;
		spin_unlock(&block_rsv->lock);
		space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
		memcpy(dest, &space, sizeof(space));
		space_args.total_spaces++;
	}

D
Daniel J Blueman 已提交
4003
	user_dest = (struct btrfs_ioctl_space_info __user *)
4004 4005 4006 4007 4008 4009 4010 4011
		(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)))
J
Josef Bacik 已提交
4012 4013 4014 4015 4016
		ret = -EFAULT;

	return ret;
}

C
Christoph Hellwig 已提交
4017 4018 4019 4020 4021 4022 4023 4024
/*
 * there are many ways the trans_start and trans_end ioctls can lead
 * to deadlocks.  They should only be used by applications that
 * basically own the machine, and have a very in depth understanding
 * of all the possible deadlocks and enospc problems.
 */
long btrfs_ioctl_trans_end(struct file *file)
{
A
Al Viro 已提交
4025
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
4026 4027 4028 4029
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;

	trans = file->private_data;
4030 4031
	if (!trans)
		return -EINVAL;
C
Christoph Hellwig 已提交
4032
	file->private_data = NULL;
4033

4034 4035
	btrfs_end_transaction(trans, root);

J
Josef Bacik 已提交
4036
	atomic_dec(&root->fs_info->open_ioctl_trans);
4037

A
Al Viro 已提交
4038
	mnt_drop_write_file(file);
4039
	return 0;
C
Christoph Hellwig 已提交
4040 4041
}

4042 4043
static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
					    void __user *argp)
4044 4045 4046
{
	struct btrfs_trans_handle *trans;
	u64 transid;
T
Tsutomu Itoh 已提交
4047
	int ret;
4048

M
Miao Xie 已提交
4049
	trans = btrfs_attach_transaction_barrier(root);
4050 4051 4052 4053 4054 4055 4056 4057
	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;
	}
4058
	transid = trans->transid;
T
Tsutomu Itoh 已提交
4059
	ret = btrfs_commit_transaction_async(trans, root, 0);
4060 4061
	if (ret) {
		btrfs_end_transaction(trans, root);
T
Tsutomu Itoh 已提交
4062
		return ret;
4063
	}
4064
out:
4065 4066 4067 4068 4069 4070
	if (argp)
		if (copy_to_user(argp, &transid, sizeof(transid)))
			return -EFAULT;
	return 0;
}

4071 4072
static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
					   void __user *argp)
4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084
{
	u64 transid;

	if (argp) {
		if (copy_from_user(&transid, argp, sizeof(transid)))
			return -EFAULT;
	} else {
		transid = 0;  /* current trans */
	}
	return btrfs_wait_for_commit(root, transid);
}

M
Miao Xie 已提交
4085
static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
J
Jan Schmidt 已提交
4086
{
A
Al Viro 已提交
4087
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4088
	struct btrfs_ioctl_scrub_args *sa;
M
Miao Xie 已提交
4089
	int ret;
J
Jan Schmidt 已提交
4090 4091 4092 4093 4094 4095 4096 4097

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	sa = memdup_user(arg, sizeof(*sa));
	if (IS_ERR(sa))
		return PTR_ERR(sa);

M
Miao Xie 已提交
4098 4099 4100 4101 4102 4103
	if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
		ret = mnt_want_write_file(file);
		if (ret)
			goto out;
	}

4104
	ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4105 4106
			      &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
			      0);
J
Jan Schmidt 已提交
4107 4108 4109 4110

	if (copy_to_user(arg, sa, sizeof(*sa)))
		ret = -EFAULT;

M
Miao Xie 已提交
4111 4112 4113
	if (!(sa->flags & BTRFS_SCRUB_READONLY))
		mnt_drop_write_file(file);
out:
J
Jan Schmidt 已提交
4114 4115 4116 4117 4118 4119 4120 4121 4122
	kfree(sa);
	return ret;
}

static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
{
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4123
	return btrfs_scrub_cancel(root->fs_info);
J
Jan Schmidt 已提交
4124 4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145 4146 4147
}

static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
				       void __user *arg)
{
	struct btrfs_ioctl_scrub_args *sa;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	sa = memdup_user(arg, sizeof(*sa));
	if (IS_ERR(sa))
		return PTR_ERR(sa);

	ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);

	if (copy_to_user(arg, sa, sizeof(*sa)))
		ret = -EFAULT;

	kfree(sa);
	return ret;
}

4148
static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4149
				      void __user *arg)
4150 4151 4152 4153 4154 4155 4156 4157
{
	struct btrfs_ioctl_get_dev_stats *sa;
	int ret;

	sa = memdup_user(arg, sizeof(*sa));
	if (IS_ERR(sa))
		return PTR_ERR(sa);

4158 4159 4160 4161 4162 4163
	if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
		kfree(sa);
		return -EPERM;
	}

	ret = btrfs_get_dev_stats(root, sa);
4164 4165 4166 4167 4168 4169 4170 4171

	if (copy_to_user(arg, sa, sizeof(*sa)))
		ret = -EFAULT;

	kfree(sa);
	return ret;
}

4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185
static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
{
	struct btrfs_ioctl_dev_replace_args *p;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	p = memdup_user(arg, sizeof(*p));
	if (IS_ERR(p))
		return PTR_ERR(p);

	switch (p->cmd) {
	case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4186 4187 4188 4189
		if (root->fs_info->sb->s_flags & MS_RDONLY) {
			ret = -EROFS;
			goto out;
		}
4190 4191 4192
		if (atomic_xchg(
			&root->fs_info->mutually_exclusive_operation_running,
			1)) {
4193
			ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4194 4195 4196 4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207 4208 4209 4210 4211 4212 4213 4214
		} else {
			ret = btrfs_dev_replace_start(root, p);
			atomic_set(
			 &root->fs_info->mutually_exclusive_operation_running,
			 0);
		}
		break;
	case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
		btrfs_dev_replace_status(root->fs_info, p);
		ret = 0;
		break;
	case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
		ret = btrfs_dev_replace_cancel(root->fs_info, p);
		break;
	default:
		ret = -EINVAL;
		break;
	}

	if (copy_to_user(arg, p, sizeof(*p)))
		ret = -EFAULT;
4215
out:
4216 4217 4218 4219
	kfree(p);
	return ret;
}

4220 4221 4222 4223
static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
{
	int ret = 0;
	int i;
4224
	u64 rel_ptr;
4225
	int size;
4226
	struct btrfs_ioctl_ino_path_args *ipa = NULL;
4227 4228 4229
	struct inode_fs_paths *ipath = NULL;
	struct btrfs_path *path;

4230
	if (!capable(CAP_DAC_READ_SEARCH))
4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249 4250 4251 4252 4253 4254 4255 4256 4257 4258
		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) {
4259 4260
		rel_ptr = ipath->fspath->val[i] -
			  (u64)(unsigned long)ipath->fspath->val;
4261
		ipath->fspath->val[i] = rel_ptr;
4262 4263
	}

4264 4265
	ret = copy_to_user((void *)(unsigned long)ipa->fspath,
			   (void *)(unsigned long)ipath->fspath, size);
4266 4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307 4308 4309 4310 4311 4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322 4323
	if (ret) {
		ret = -EFAULT;
		goto out;
	}

out:
	btrfs_free_path(path);
	free_ipath(ipath);
	kfree(ipa);

	return ret;
}

static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
{
	struct btrfs_data_container *inodes = ctx;
	const size_t c = 3 * sizeof(u64);

	if (inodes->bytes_left >= c) {
		inodes->bytes_left -= c;
		inodes->val[inodes->elem_cnt] = inum;
		inodes->val[inodes->elem_cnt + 1] = offset;
		inodes->val[inodes->elem_cnt + 2] = root;
		inodes->elem_cnt += 3;
	} else {
		inodes->bytes_missing += c - inodes->bytes_left;
		inodes->bytes_left = 0;
		inodes->elem_missed += 3;
	}

	return 0;
}

static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
					void __user *arg)
{
	int ret = 0;
	int size;
	struct btrfs_ioctl_logical_ino_args *loi;
	struct btrfs_data_container *inodes = NULL;
	struct btrfs_path *path = NULL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	loi = memdup_user(arg, sizeof(*loi));
	if (IS_ERR(loi)) {
		ret = PTR_ERR(loi);
		loi = NULL;
		goto out;
	}

	path = btrfs_alloc_path();
	if (!path) {
		ret = -ENOMEM;
		goto out;
	}

4324
	size = min_t(u32, loi->size, 64 * 1024);
4325 4326 4327 4328 4329 4330 4331
	inodes = init_data_container(size);
	if (IS_ERR(inodes)) {
		ret = PTR_ERR(inodes);
		inodes = NULL;
		goto out;
	}

L
Liu Bo 已提交
4332 4333 4334
	ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
					  build_ino_list, inodes);
	if (ret == -EINVAL)
4335 4336 4337 4338
		ret = -ENOENT;
	if (ret < 0)
		goto out;

4339 4340
	ret = copy_to_user((void *)(unsigned long)loi->inodes,
			   (void *)(unsigned long)inodes, size);
4341 4342 4343 4344 4345
	if (ret)
		ret = -EFAULT;

out:
	btrfs_free_path(path);
4346
	vfree(inodes);
4347 4348 4349 4350 4351
	kfree(loi);

	return ret;
}

4352
void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4353 4354 4355 4356 4357 4358
			       struct btrfs_ioctl_balance_args *bargs)
{
	struct btrfs_balance_control *bctl = fs_info->balance_ctl;

	bargs->flags = bctl->flags;

4359 4360 4361 4362
	if (atomic_read(&fs_info->balance_running))
		bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
	if (atomic_read(&fs_info->balance_pause_req))
		bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4363 4364
	if (atomic_read(&fs_info->balance_cancel_req))
		bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4365

4366 4367 4368
	memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
	memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
	memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4369 4370 4371 4372 4373 4374 4375 4376

	if (lock) {
		spin_lock(&fs_info->balance_lock);
		memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
		spin_unlock(&fs_info->balance_lock);
	} else {
		memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
	}
4377 4378
}

4379
static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4380
{
A
Al Viro 已提交
4381
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4382 4383 4384
	struct btrfs_fs_info *fs_info = root->fs_info;
	struct btrfs_ioctl_balance_args *bargs;
	struct btrfs_balance_control *bctl;
4385
	bool need_unlock; /* for mut. excl. ops lock */
4386 4387 4388 4389 4390
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4391
	ret = mnt_want_write_file(file);
4392 4393 4394
	if (ret)
		return ret;

4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408
again:
	if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
		mutex_lock(&fs_info->volume_mutex);
		mutex_lock(&fs_info->balance_mutex);
		need_unlock = true;
		goto locked;
	}

	/*
	 * mut. excl. ops lock is locked.  Three possibilites:
	 *   (1) some other op is running
	 *   (2) balance is running
	 *   (3) balance is paused -- special case (think resume)
	 */
4409
	mutex_lock(&fs_info->balance_mutex);
4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436
	if (fs_info->balance_ctl) {
		/* this is either (2) or (3) */
		if (!atomic_read(&fs_info->balance_running)) {
			mutex_unlock(&fs_info->balance_mutex);
			if (!mutex_trylock(&fs_info->volume_mutex))
				goto again;
			mutex_lock(&fs_info->balance_mutex);

			if (fs_info->balance_ctl &&
			    !atomic_read(&fs_info->balance_running)) {
				/* this is (3) */
				need_unlock = false;
				goto locked;
			}

			mutex_unlock(&fs_info->balance_mutex);
			mutex_unlock(&fs_info->volume_mutex);
			goto again;
		} else {
			/* this is (2) */
			mutex_unlock(&fs_info->balance_mutex);
			ret = -EINPROGRESS;
			goto out;
		}
	} else {
		/* this is (1) */
		mutex_unlock(&fs_info->balance_mutex);
4437
		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4438 4439 4440 4441 4442
		goto out;
	}

locked:
	BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4443 4444 4445 4446 4447

	if (arg) {
		bargs = memdup_user(arg, sizeof(*bargs));
		if (IS_ERR(bargs)) {
			ret = PTR_ERR(bargs);
4448
			goto out_unlock;
4449
		}
4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462 4463

		if (bargs->flags & BTRFS_BALANCE_RESUME) {
			if (!fs_info->balance_ctl) {
				ret = -ENOTCONN;
				goto out_bargs;
			}

			bctl = fs_info->balance_ctl;
			spin_lock(&fs_info->balance_lock);
			bctl->flags |= BTRFS_BALANCE_RESUME;
			spin_unlock(&fs_info->balance_lock);

			goto do_balance;
		}
4464 4465 4466 4467
	} else {
		bargs = NULL;
	}

4468
	if (fs_info->balance_ctl) {
4469 4470 4471 4472
		ret = -EINPROGRESS;
		goto out_bargs;
	}

4473 4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484 4485
	bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
	if (!bctl) {
		ret = -ENOMEM;
		goto out_bargs;
	}

	bctl->fs_info = fs_info;
	if (arg) {
		memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
		memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
		memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));

		bctl->flags = bargs->flags;
4486 4487 4488
	} else {
		/* balance everything - no filters */
		bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4489 4490
	}

4491
do_balance:
4492
	/*
4493 4494 4495 4496 4497
	 * Ownership of bctl and mutually_exclusive_operation_running
	 * goes to to btrfs_balance.  bctl is freed in __cancel_balance,
	 * or, if restriper was paused all the way until unmount, in
	 * free_fs_info.  mutually_exclusive_operation_running is
	 * cleared in __cancel_balance.
4498
	 */
4499 4500 4501 4502
	need_unlock = false;

	ret = btrfs_balance(bctl, bargs);

4503 4504 4505 4506 4507 4508 4509
	if (arg) {
		if (copy_to_user(arg, bargs, sizeof(*bargs)))
			ret = -EFAULT;
	}

out_bargs:
	kfree(bargs);
4510
out_unlock:
4511 4512
	mutex_unlock(&fs_info->balance_mutex);
	mutex_unlock(&fs_info->volume_mutex);
4513 4514 4515
	if (need_unlock)
		atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
out:
4516
	mnt_drop_write_file(file);
4517 4518 4519
	return ret;
}

4520 4521 4522 4523 4524 4525 4526 4527
static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
{
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	switch (cmd) {
	case BTRFS_BALANCE_CTL_PAUSE:
		return btrfs_pause_balance(root->fs_info);
4528 4529
	case BTRFS_BALANCE_CTL_CANCEL:
		return btrfs_cancel_balance(root->fs_info);
4530 4531 4532 4533 4534
	}

	return -EINVAL;
}

4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567
static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
					 void __user *arg)
{
	struct btrfs_fs_info *fs_info = root->fs_info;
	struct btrfs_ioctl_balance_args *bargs;
	int ret = 0;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	mutex_lock(&fs_info->balance_mutex);
	if (!fs_info->balance_ctl) {
		ret = -ENOTCONN;
		goto out;
	}

	bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
	if (!bargs) {
		ret = -ENOMEM;
		goto out;
	}

	update_ioctl_balance_args(fs_info, 1, bargs);

	if (copy_to_user(arg, bargs, sizeof(*bargs)))
		ret = -EFAULT;

	kfree(bargs);
out:
	mutex_unlock(&fs_info->balance_mutex);
	return ret;
}

4568
static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4569
{
A
Al Viro 已提交
4570
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4571 4572 4573 4574 4575 4576 4577 4578
	struct btrfs_ioctl_quota_ctl_args *sa;
	struct btrfs_trans_handle *trans = NULL;
	int ret;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4579 4580 4581
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4582 4583

	sa = memdup_user(arg, sizeof(*sa));
4584 4585 4586 4587
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4588

4589
	down_write(&root->fs_info->subvol_sem);
J
Jan Schmidt 已提交
4590 4591 4592 4593
	trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
A
Arne Jansen 已提交
4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607
	}

	switch (sa->cmd) {
	case BTRFS_QUOTA_CTL_ENABLE:
		ret = btrfs_quota_enable(trans, root->fs_info);
		break;
	case BTRFS_QUOTA_CTL_DISABLE:
		ret = btrfs_quota_disable(trans, root->fs_info);
		break;
	default:
		ret = -EINVAL;
		break;
	}

J
Jan Schmidt 已提交
4608 4609 4610
	err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
	if (err && !ret)
		ret = err;
A
Arne Jansen 已提交
4611 4612
out:
	kfree(sa);
4613
	up_write(&root->fs_info->subvol_sem);
4614 4615
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4616 4617 4618
	return ret;
}

4619
static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4620
{
A
Al Viro 已提交
4621
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4622 4623 4624 4625 4626 4627 4628 4629
	struct btrfs_ioctl_qgroup_assign_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4630 4631 4632
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4633 4634

	sa = memdup_user(arg, sizeof(*sa));
4635 4636 4637 4638
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659 4660

	trans = btrfs_join_transaction(root);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
	}

	/* FIXME: check if the IDs really exist */
	if (sa->assign) {
		ret = btrfs_add_qgroup_relation(trans, root->fs_info,
						sa->src, sa->dst);
	} else {
		ret = btrfs_del_qgroup_relation(trans, root->fs_info,
						sa->src, sa->dst);
	}

	err = btrfs_end_transaction(trans, root);
	if (err && !ret)
		ret = err;

out:
	kfree(sa);
4661 4662
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4663 4664 4665
	return ret;
}

4666
static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4667
{
A
Al Viro 已提交
4668
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4669 4670 4671 4672 4673 4674 4675 4676
	struct btrfs_ioctl_qgroup_create_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4677 4678 4679
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4680 4681

	sa = memdup_user(arg, sizeof(*sa));
4682 4683 4684 4685
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4686

M
Miao Xie 已提交
4687 4688 4689 4690 4691
	if (!sa->qgroupid) {
		ret = -EINVAL;
		goto out;
	}

A
Arne Jansen 已提交
4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710 4711
	trans = btrfs_join_transaction(root);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
	}

	/* FIXME: check if the IDs really exist */
	if (sa->create) {
		ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
					  NULL);
	} else {
		ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
	}

	err = btrfs_end_transaction(trans, root);
	if (err && !ret)
		ret = err;

out:
	kfree(sa);
4712 4713
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4714 4715 4716
	return ret;
}

4717
static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4718
{
A
Al Viro 已提交
4719
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4720 4721 4722 4723 4724 4725 4726 4727 4728
	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;

4729 4730 4731
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4732 4733

	sa = memdup_user(arg, sizeof(*sa));
4734 4735 4736 4737
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759

	trans = btrfs_join_transaction(root);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
	}

	qgroupid = sa->qgroupid;
	if (!qgroupid) {
		/* take the current subvol as qgroup */
		qgroupid = root->root_key.objectid;
	}

	/* FIXME: check if the IDs really exist */
	ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);

	err = btrfs_end_transaction(trans, root);
	if (err && !ret)
		ret = err;

out:
	kfree(sa);
4760 4761
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4762 4763 4764
	return ret;
}

J
Jan Schmidt 已提交
4765 4766
static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4767
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799
	struct btrfs_ioctl_quota_rescan_args *qsa;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	qsa = memdup_user(arg, sizeof(*qsa));
	if (IS_ERR(qsa)) {
		ret = PTR_ERR(qsa);
		goto drop_write;
	}

	if (qsa->flags) {
		ret = -EINVAL;
		goto out;
	}

	ret = btrfs_qgroup_rescan(root->fs_info);

out:
	kfree(qsa);
drop_write:
	mnt_drop_write_file(file);
	return ret;
}

static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4800
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820 4821 4822
	struct btrfs_ioctl_quota_rescan_args *qsa;
	int ret = 0;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
	if (!qsa)
		return -ENOMEM;

	if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
		qsa->flags = 1;
		qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
	}

	if (copy_to_user(arg, qsa, sizeof(*qsa)))
		ret = -EFAULT;

	kfree(qsa);
	return ret;
}

4823 4824
static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4825
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4826 4827 4828 4829 4830 4831 4832

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	return btrfs_qgroup_wait_for_completion(root->fs_info);
}

4833 4834
static long _btrfs_ioctl_set_received_subvol(struct file *file,
					    struct btrfs_ioctl_received_subvol_args *sa)
4835
{
A
Al Viro 已提交
4836
	struct inode *inode = file_inode(file);
4837 4838 4839 4840 4841
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_root_item *root_item = &root->root_item;
	struct btrfs_trans_handle *trans;
	struct timespec ct = CURRENT_TIME;
	int ret = 0;
4842
	int received_uuid_changed;
4843

4844 4845 4846
	if (!inode_owner_or_capable(inode))
		return -EPERM;

4847 4848 4849 4850 4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861 4862
	ret = mnt_want_write_file(file);
	if (ret < 0)
		return ret;

	down_write(&root->fs_info->subvol_sem);

	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
		ret = -EINVAL;
		goto out;
	}

	if (btrfs_root_readonly(root)) {
		ret = -EROFS;
		goto out;
	}

4863 4864 4865 4866 4867
	/*
	 * 1 - root item
	 * 2 - uuid items (received uuid + subvol uuid)
	 */
	trans = btrfs_start_transaction(root, 3);
4868 4869 4870 4871 4872 4873 4874 4875 4876 4877
	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;

4878 4879 4880 4881 4882 4883 4884 4885
	received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
				       BTRFS_UUID_SIZE);
	if (received_uuid_changed &&
	    !btrfs_is_empty_uuid(root_item->received_uuid))
		btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
				    root_item->received_uuid,
				    BTRFS_UUID_KEY_RECEIVED_SUBVOL,
				    root->root_key.objectid);
4886 4887 4888
	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);
4889 4890 4891 4892
	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);
4893 4894 4895 4896 4897 4898

	ret = btrfs_update_root(trans, root->fs_info->tree_root,
				&root->root_key, &root->root_item);
	if (ret < 0) {
		btrfs_end_transaction(trans, root);
		goto out;
4899 4900 4901 4902 4903 4904 4905 4906
	}
	if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
		ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
					  sa->uuid,
					  BTRFS_UUID_KEY_RECEIVED_SUBVOL,
					  root->root_key.objectid);
		if (ret < 0 && ret != -EEXIST) {
			btrfs_abort_transaction(trans, root, ret);
4907
			goto out;
4908 4909 4910 4911 4912 4913
		}
	}
	ret = btrfs_commit_transaction(trans, root);
	if (ret < 0) {
		btrfs_abort_transaction(trans, root, ret);
		goto out;
4914 4915
	}

4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937
out:
	up_write(&root->fs_info->subvol_sem);
	mnt_drop_write_file(file);
	return ret;
}

#ifdef CONFIG_64BIT
static long btrfs_ioctl_set_received_subvol_32(struct file *file,
						void __user *arg)
{
	struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
	struct btrfs_ioctl_received_subvol_args *args64 = NULL;
	int ret = 0;

	args32 = memdup_user(arg, sizeof(*args32));
	if (IS_ERR(args32)) {
		ret = PTR_ERR(args32);
		args32 = NULL;
		goto out;
	}

	args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4938 4939
	if (!args64) {
		ret = -ENOMEM;
4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992 4993
		goto out;
	}

	memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
	args64->stransid = args32->stransid;
	args64->rtransid = args32->rtransid;
	args64->stime.sec = args32->stime.sec;
	args64->stime.nsec = args32->stime.nsec;
	args64->rtime.sec = args32->rtime.sec;
	args64->rtime.nsec = args32->rtime.nsec;
	args64->flags = args32->flags;

	ret = _btrfs_ioctl_set_received_subvol(file, args64);
	if (ret)
		goto out;

	memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
	args32->stransid = args64->stransid;
	args32->rtransid = args64->rtransid;
	args32->stime.sec = args64->stime.sec;
	args32->stime.nsec = args64->stime.nsec;
	args32->rtime.sec = args64->rtime.sec;
	args32->rtime.nsec = args64->rtime.nsec;
	args32->flags = args64->flags;

	ret = copy_to_user(arg, args32, sizeof(*args32));
	if (ret)
		ret = -EFAULT;

out:
	kfree(args32);
	kfree(args64);
	return ret;
}
#endif

static long btrfs_ioctl_set_received_subvol(struct file *file,
					    void __user *arg)
{
	struct btrfs_ioctl_received_subvol_args *sa = NULL;
	int ret = 0;

	sa = memdup_user(arg, sizeof(*sa));
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		sa = NULL;
		goto out;
	}

	ret = _btrfs_ioctl_set_received_subvol(file, sa);

	if (ret)
		goto out;

4994 4995 4996 4997 4998 4999 5000 5001 5002
	ret = copy_to_user(arg, sa, sizeof(*sa));
	if (ret)
		ret = -EFAULT;

out:
	kfree(sa);
	return ret;
}

5003 5004
static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
{
A
Al Viro 已提交
5005
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5006
	size_t len;
5007
	int ret;
5008 5009 5010 5011 5012 5013 5014
	char label[BTRFS_LABEL_SIZE];

	spin_lock(&root->fs_info->super_lock);
	memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
	spin_unlock(&root->fs_info->super_lock);

	len = strnlen(label, BTRFS_LABEL_SIZE);
5015 5016

	if (len == BTRFS_LABEL_SIZE) {
5017 5018
		btrfs_warn(root->fs_info,
			"label is too long, return the first %zu bytes", --len);
5019 5020 5021 5022 5023 5024 5025
	}

	ret = copy_to_user(arg, label, len);

	return ret ? -EFAULT : 0;
}

5026 5027
static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
{
A
Al Viro 已提交
5028
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040
	struct btrfs_super_block *super_block = root->fs_info->super_copy;
	struct btrfs_trans_handle *trans;
	char label[BTRFS_LABEL_SIZE];
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (copy_from_user(label, arg, sizeof(label)))
		return -EFAULT;

	if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5041
		btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055
		       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;
	}

5056
	spin_lock(&root->fs_info->super_lock);
5057
	strcpy(super_block->label, label);
5058
	spin_unlock(&root->fs_info->super_lock);
5059
	ret = btrfs_commit_transaction(trans, root);
5060 5061 5062 5063 5064 5065

out_unlock:
	mnt_drop_write_file(file);
	return ret;
}

5066 5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101
#define INIT_FEATURE_FLAGS(suffix) \
	{ .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
	  .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
	  .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }

static int btrfs_ioctl_get_supported_features(struct file *file,
					      void __user *arg)
{
	static struct btrfs_ioctl_feature_flags features[3] = {
		INIT_FEATURE_FLAGS(SUPP),
		INIT_FEATURE_FLAGS(SAFE_SET),
		INIT_FEATURE_FLAGS(SAFE_CLEAR)
	};

	if (copy_to_user(arg, &features, sizeof(features)))
		return -EFAULT;

	return 0;
}

static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
{
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
	struct btrfs_super_block *super_block = root->fs_info->super_copy;
	struct btrfs_ioctl_feature_flags features;

	features.compat_flags = btrfs_super_compat_flags(super_block);
	features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
	features.incompat_flags = btrfs_super_incompat_flags(super_block);

	if (copy_to_user(arg, &features, sizeof(features)))
		return -EFAULT;

	return 0;
}

5102 5103
static int check_feature_bits(struct btrfs_root *root,
			      enum btrfs_feature_set set,
5104 5105 5106
			      u64 change_mask, u64 flags, u64 supported_flags,
			      u64 safe_set, u64 safe_clear)
{
5107 5108
	const char *type = btrfs_feature_set_names[set];
	char *names;
5109 5110 5111 5112 5113 5114
	u64 disallowed, unsupported;
	u64 set_mask = flags & change_mask;
	u64 clear_mask = ~flags & change_mask;

	unsupported = set_mask & ~supported_flags;
	if (unsupported) {
5115 5116 5117 5118 5119 5120 5121 5122
		names = btrfs_printable_features(set, unsupported);
		if (names) {
			btrfs_warn(root->fs_info,
			   "this kernel does not support the %s feature bit%s",
			   names, strchr(names, ',') ? "s" : "");
			kfree(names);
		} else
			btrfs_warn(root->fs_info,
5123 5124 5125 5126 5127 5128 5129
			   "this kernel does not support %s bits 0x%llx",
			   type, unsupported);
		return -EOPNOTSUPP;
	}

	disallowed = set_mask & ~safe_set;
	if (disallowed) {
5130 5131 5132 5133 5134 5135 5136 5137
		names = btrfs_printable_features(set, disallowed);
		if (names) {
			btrfs_warn(root->fs_info,
			   "can't set the %s feature bit%s while mounted",
			   names, strchr(names, ',') ? "s" : "");
			kfree(names);
		} else
			btrfs_warn(root->fs_info,
5138 5139 5140 5141 5142 5143 5144
			   "can't set %s bits 0x%llx while mounted",
			   type, disallowed);
		return -EPERM;
	}

	disallowed = clear_mask & ~safe_clear;
	if (disallowed) {
5145 5146 5147 5148 5149 5150 5151 5152
		names = btrfs_printable_features(set, disallowed);
		if (names) {
			btrfs_warn(root->fs_info,
			   "can't clear the %s feature bit%s while mounted",
			   names, strchr(names, ',') ? "s" : "");
			kfree(names);
		} else
			btrfs_warn(root->fs_info,
5153 5154 5155 5156 5157 5158 5159 5160 5161
			   "can't clear %s bits 0x%llx while mounted",
			   type, disallowed);
		return -EPERM;
	}

	return 0;
}

#define check_feature(root, change_mask, flags, mask_base)	\
5162
check_feature_bits(root, FEAT_##mask_base, change_mask, flags,	\
5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197 5198 5199 5200 5201
		   BTRFS_FEATURE_ ## mask_base ## _SUPP,	\
		   BTRFS_FEATURE_ ## mask_base ## _SAFE_SET,	\
		   BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)

static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
{
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
	struct btrfs_super_block *super_block = root->fs_info->super_copy;
	struct btrfs_ioctl_feature_flags flags[2];
	struct btrfs_trans_handle *trans;
	u64 newflags;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (copy_from_user(flags, arg, sizeof(flags)))
		return -EFAULT;

	/* Nothing to do */
	if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
	    !flags[0].incompat_flags)
		return 0;

	ret = check_feature(root, flags[0].compat_flags,
			    flags[1].compat_flags, COMPAT);
	if (ret)
		return ret;

	ret = check_feature(root, flags[0].compat_ro_flags,
			    flags[1].compat_ro_flags, COMPAT_RO);
	if (ret)
		return ret;

	ret = check_feature(root, flags[0].incompat_flags,
			    flags[1].incompat_flags, INCOMPAT);
	if (ret)
		return ret;

5202
	trans = btrfs_start_transaction(root, 0);
5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219 5220 5221 5222
	if (IS_ERR(trans))
		return PTR_ERR(trans);

	spin_lock(&root->fs_info->super_lock);
	newflags = btrfs_super_compat_flags(super_block);
	newflags |= flags[0].compat_flags & flags[1].compat_flags;
	newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
	btrfs_set_super_compat_flags(super_block, newflags);

	newflags = btrfs_super_compat_ro_flags(super_block);
	newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
	newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
	btrfs_set_super_compat_ro_flags(super_block, newflags);

	newflags = btrfs_super_incompat_flags(super_block);
	newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
	newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
	btrfs_set_super_incompat_flags(super_block, newflags);
	spin_unlock(&root->fs_info->super_lock);

5223
	return btrfs_commit_transaction(trans, root);
5224 5225
}

C
Christoph Hellwig 已提交
5226 5227 5228
long btrfs_ioctl(struct file *file, unsigned int
		cmd, unsigned long arg)
{
A
Al Viro 已提交
5229
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5230
	void __user *argp = (void __user *)arg;
C
Christoph Hellwig 已提交
5231 5232

	switch (cmd) {
5233 5234 5235 5236 5237 5238
	case FS_IOC_GETFLAGS:
		return btrfs_ioctl_getflags(file, argp);
	case FS_IOC_SETFLAGS:
		return btrfs_ioctl_setflags(file, argp);
	case FS_IOC_GETVERSION:
		return btrfs_ioctl_getversion(file, argp);
5239 5240
	case FITRIM:
		return btrfs_ioctl_fitrim(file, argp);
C
Christoph Hellwig 已提交
5241
	case BTRFS_IOC_SNAP_CREATE:
5242
		return btrfs_ioctl_snap_create(file, argp, 0);
5243
	case BTRFS_IOC_SNAP_CREATE_V2:
5244
		return btrfs_ioctl_snap_create_v2(file, argp, 0);
5245
	case BTRFS_IOC_SUBVOL_CREATE:
5246
		return btrfs_ioctl_snap_create(file, argp, 1);
A
Arne Jansen 已提交
5247 5248
	case BTRFS_IOC_SUBVOL_CREATE_V2:
		return btrfs_ioctl_snap_create_v2(file, argp, 1);
5249 5250
	case BTRFS_IOC_SNAP_DESTROY:
		return btrfs_ioctl_snap_destroy(file, argp);
5251 5252 5253 5254
	case BTRFS_IOC_SUBVOL_GETFLAGS:
		return btrfs_ioctl_subvol_getflags(file, argp);
	case BTRFS_IOC_SUBVOL_SETFLAGS:
		return btrfs_ioctl_subvol_setflags(file, argp);
5255 5256
	case BTRFS_IOC_DEFAULT_SUBVOL:
		return btrfs_ioctl_default_subvol(file, argp);
C
Christoph Hellwig 已提交
5257
	case BTRFS_IOC_DEFRAG:
C
Chris Mason 已提交
5258 5259 5260
		return btrfs_ioctl_defrag(file, NULL);
	case BTRFS_IOC_DEFRAG_RANGE:
		return btrfs_ioctl_defrag(file, argp);
C
Christoph Hellwig 已提交
5261
	case BTRFS_IOC_RESIZE:
5262
		return btrfs_ioctl_resize(file, argp);
C
Christoph Hellwig 已提交
5263
	case BTRFS_IOC_ADD_DEV:
5264
		return btrfs_ioctl_add_dev(root, argp);
C
Christoph Hellwig 已提交
5265
	case BTRFS_IOC_RM_DEV:
5266
		return btrfs_ioctl_rm_dev(file, argp);
J
Jan Schmidt 已提交
5267 5268 5269 5270
	case BTRFS_IOC_FS_INFO:
		return btrfs_ioctl_fs_info(root, argp);
	case BTRFS_IOC_DEV_INFO:
		return btrfs_ioctl_dev_info(root, argp);
C
Christoph Hellwig 已提交
5271
	case BTRFS_IOC_BALANCE:
5272
		return btrfs_ioctl_balance(file, NULL);
C
Christoph Hellwig 已提交
5273
	case BTRFS_IOC_CLONE:
5274 5275
		return btrfs_ioctl_clone(file, arg, 0, 0, 0);
	case BTRFS_IOC_CLONE_RANGE:
5276
		return btrfs_ioctl_clone_range(file, argp);
C
Christoph Hellwig 已提交
5277 5278 5279 5280
	case BTRFS_IOC_TRANS_START:
		return btrfs_ioctl_trans_start(file);
	case BTRFS_IOC_TRANS_END:
		return btrfs_ioctl_trans_end(file);
5281 5282
	case BTRFS_IOC_TREE_SEARCH:
		return btrfs_ioctl_tree_search(file, argp);
G
Gerhard Heift 已提交
5283 5284
	case BTRFS_IOC_TREE_SEARCH_V2:
		return btrfs_ioctl_tree_search_v2(file, argp);
5285 5286
	case BTRFS_IOC_INO_LOOKUP:
		return btrfs_ioctl_ino_lookup(file, argp);
5287 5288 5289 5290
	case BTRFS_IOC_INO_PATHS:
		return btrfs_ioctl_ino_to_path(root, argp);
	case BTRFS_IOC_LOGICAL_INO:
		return btrfs_ioctl_logical_to_ino(root, argp);
J
Josef Bacik 已提交
5291 5292
	case BTRFS_IOC_SPACE_INFO:
		return btrfs_ioctl_space_info(root, argp);
5293 5294 5295
	case BTRFS_IOC_SYNC: {
		int ret;

5296
		ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5297 5298 5299
		if (ret)
			return ret;
		ret = btrfs_sync_fs(file->f_dentry->d_sb, 1);
5300 5301 5302 5303 5304 5305
		/*
		 * The transaction thread may want to do more work,
		 * namely it pokes the cleaner ktread that will start
		 * processing uncleaned subvols.
		 */
		wake_up_process(root->fs_info->transaction_kthread);
5306 5307
		return ret;
	}
5308
	case BTRFS_IOC_START_SYNC:
5309
		return btrfs_ioctl_start_sync(root, argp);
5310
	case BTRFS_IOC_WAIT_SYNC:
5311
		return btrfs_ioctl_wait_sync(root, argp);
J
Jan Schmidt 已提交
5312
	case BTRFS_IOC_SCRUB:
M
Miao Xie 已提交
5313
		return btrfs_ioctl_scrub(file, argp);
J
Jan Schmidt 已提交
5314 5315 5316 5317
	case BTRFS_IOC_SCRUB_CANCEL:
		return btrfs_ioctl_scrub_cancel(root, argp);
	case BTRFS_IOC_SCRUB_PROGRESS:
		return btrfs_ioctl_scrub_progress(root, argp);
5318
	case BTRFS_IOC_BALANCE_V2:
5319
		return btrfs_ioctl_balance(file, argp);
5320 5321
	case BTRFS_IOC_BALANCE_CTL:
		return btrfs_ioctl_balance_ctl(root, arg);
5322 5323
	case BTRFS_IOC_BALANCE_PROGRESS:
		return btrfs_ioctl_balance_progress(root, argp);
5324 5325
	case BTRFS_IOC_SET_RECEIVED_SUBVOL:
		return btrfs_ioctl_set_received_subvol(file, argp);
5326 5327 5328 5329
#ifdef CONFIG_64BIT
	case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
		return btrfs_ioctl_set_received_subvol_32(file, argp);
#endif
5330 5331
	case BTRFS_IOC_SEND:
		return btrfs_ioctl_send(file, argp);
5332
	case BTRFS_IOC_GET_DEV_STATS:
5333
		return btrfs_ioctl_get_dev_stats(root, argp);
A
Arne Jansen 已提交
5334
	case BTRFS_IOC_QUOTA_CTL:
5335
		return btrfs_ioctl_quota_ctl(file, argp);
A
Arne Jansen 已提交
5336
	case BTRFS_IOC_QGROUP_ASSIGN:
5337
		return btrfs_ioctl_qgroup_assign(file, argp);
A
Arne Jansen 已提交
5338
	case BTRFS_IOC_QGROUP_CREATE:
5339
		return btrfs_ioctl_qgroup_create(file, argp);
A
Arne Jansen 已提交
5340
	case BTRFS_IOC_QGROUP_LIMIT:
5341
		return btrfs_ioctl_qgroup_limit(file, argp);
J
Jan Schmidt 已提交
5342 5343 5344 5345
	case BTRFS_IOC_QUOTA_RESCAN:
		return btrfs_ioctl_quota_rescan(file, argp);
	case BTRFS_IOC_QUOTA_RESCAN_STATUS:
		return btrfs_ioctl_quota_rescan_status(file, argp);
5346 5347
	case BTRFS_IOC_QUOTA_RESCAN_WAIT:
		return btrfs_ioctl_quota_rescan_wait(file, argp);
5348 5349
	case BTRFS_IOC_DEV_REPLACE:
		return btrfs_ioctl_dev_replace(root, argp);
5350 5351
	case BTRFS_IOC_GET_FSLABEL:
		return btrfs_ioctl_get_fslabel(file, argp);
5352 5353
	case BTRFS_IOC_SET_FSLABEL:
		return btrfs_ioctl_set_fslabel(file, argp);
M
Mark Fasheh 已提交
5354 5355
	case BTRFS_IOC_FILE_EXTENT_SAME:
		return btrfs_ioctl_file_extent_same(file, argp);
5356 5357 5358 5359 5360 5361
	case BTRFS_IOC_GET_SUPPORTED_FEATURES:
		return btrfs_ioctl_get_supported_features(file, argp);
	case BTRFS_IOC_GET_FEATURES:
		return btrfs_ioctl_get_features(file, argp);
	case BTRFS_IOC_SET_FEATURES:
		return btrfs_ioctl_set_features(file, argp);
C
Christoph Hellwig 已提交
5362 5363 5364 5365
	}

	return -ENOTTY;
}