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 {
		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);
		}
	}
395
	rcu_read_unlock();
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	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)
403
		return -EINVAL;
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405
	range.len = min(range.len, total_bytes - range.start);
406
	range.minlen = max(range.minlen, minlen);
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	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;
}

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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;
426 427
}

428
static noinline int create_subvol(struct inode *dir,
429
				  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;
439
	struct btrfs_root *root = BTRFS_I(dir)->root;
440
	struct btrfs_root *new_root;
441
	struct btrfs_block_rsv block_rsv;
442
	struct timespec cur_time = CURRENT_TIME;
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	struct inode *inode;
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	int ret;
	int err;
	u64 objectid;
	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
448
	u64 index = 0;
449
	u64 qgroup_reserved;
450
	uuid_le new_uuid;
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452
	ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
453
	if (ret)
454
		return ret;
455

456
	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
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	/*
458 459
	 * The same as the snapshot creation, please see the comment
	 * of create_snapshot().
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	 */
461
	ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
462
					       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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476
	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_free_block(trans, root, root->leafsize,
481
				      0, objectid, NULL, 0, 0, 0);
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	if (IS_ERR(leaf)) {
		ret = PTR_ERR(leaf);
		goto fail;
	}
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487
	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);

493
	write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
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			    BTRFS_FSID_SIZE);
495
	write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
496
			    btrfs_header_chunk_tree_uuid(leaf),
497
			    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);
	btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
	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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530
	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;
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	key.offset = 0;
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	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
	ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
				&root_item);
	if (ret)
		goto fail;

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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;
	}
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	btrfs_record_root_in_trans(trans, new_root);

554
	ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
555 556
	if (ret) {
		/* We potentially lose an unused inode item here */
557
		btrfs_abort_transaction(trans, root, ret);
558 559 560
		goto fail;
	}

C
Christoph Hellwig 已提交
561 562 563
	/*
	 * insert the directory item
	 */
564
	ret = btrfs_set_inode_index(dir, &index);
565 566 567 568
	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
		goto fail;
	}
569 570

	ret = btrfs_insert_dir_item(trans, root,
571
				    name, namelen, dir, &key,
572
				    BTRFS_FT_DIR, index);
573 574
	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
C
Christoph Hellwig 已提交
575
		goto fail;
576
	}
577

578 579 580 581
	btrfs_i_size_write(dir, dir->i_size + namelen * 2);
	ret = btrfs_update_inode(trans, root, dir);
	BUG_ON(ret);

582
	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
583
				 objectid, root->root_key.objectid,
L
Li Zefan 已提交
584
				 btrfs_ino(dir), index, name, namelen);
585
	BUG_ON(ret);
C
Christoph Hellwig 已提交
586

587 588 589 590 591 592
	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
593
fail:
594 595
	trans->block_rsv = NULL;
	trans->bytes_reserved = 0;
596 597
	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);

S
Sage Weil 已提交
598 599 600
	if (async_transid) {
		*async_transid = trans->transid;
		err = btrfs_commit_transaction_async(trans, root, 1);
601 602
		if (err)
			err = btrfs_commit_transaction(trans, root);
S
Sage Weil 已提交
603 604 605
	} else {
		err = btrfs_commit_transaction(trans, root);
	}
C
Christoph Hellwig 已提交
606 607
	if (err && !ret)
		ret = err;
608

609 610
	if (!ret) {
		inode = btrfs_lookup_dentry(dir, dentry);
611 612
		if (IS_ERR(inode))
			return PTR_ERR(inode);
613 614
		d_instantiate(dentry, inode);
	}
C
Christoph Hellwig 已提交
615 616 617
	return ret;
}

618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634
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);
}

635 636 637 638
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
639
{
640
	struct inode *inode;
C
Christoph Hellwig 已提交
641 642
	struct btrfs_pending_snapshot *pending_snapshot;
	struct btrfs_trans_handle *trans;
643
	int ret;
C
Christoph Hellwig 已提交
644

645
	if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
C
Christoph Hellwig 已提交
646 647
		return -EINVAL;

648 649 650 651
	atomic_inc(&root->will_be_snapshoted);
	smp_mb__after_atomic_inc();
	btrfs_wait_nocow_write(root);

652 653
	ret = btrfs_start_delalloc_inodes(root, 0);
	if (ret)
654
		goto out;
655

656
	btrfs_wait_ordered_extents(root, -1);
657

658
	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
659 660 661 662
	if (!pending_snapshot) {
		ret = -ENOMEM;
		goto out;
	}
663

664 665
	btrfs_init_block_rsv(&pending_snapshot->block_rsv,
			     BTRFS_BLOCK_RSV_TEMP);
666 667 668 669 670 671
	/*
	 * 1 - parent dir inode
	 * 2 - dir entries
	 * 1 - root item
	 * 2 - root ref/backref
	 * 1 - root of snapshot
672
	 * 1 - UUID item
673 674
	 */
	ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
675
					&pending_snapshot->block_rsv, 8,
676 677
					&pending_snapshot->qgroup_reserved,
					false);
678
	if (ret)
679
		goto free;
680

681
	pending_snapshot->dentry = dentry;
C
Christoph Hellwig 已提交
682
	pending_snapshot->root = root;
L
Li Zefan 已提交
683
	pending_snapshot->readonly = readonly;
684
	pending_snapshot->dir = dir;
685
	pending_snapshot->inherit = inherit;
686

687
	trans = btrfs_start_transaction(root, 0);
688 689 690 691 692
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto fail;
	}

693
	spin_lock(&root->fs_info->trans_lock);
C
Christoph Hellwig 已提交
694 695
	list_add(&pending_snapshot->list,
		 &trans->transaction->pending_snapshots);
696
	spin_unlock(&root->fs_info->trans_lock);
S
Sage Weil 已提交
697 698 699 700
	if (async_transid) {
		*async_transid = trans->transid;
		ret = btrfs_commit_transaction_async(trans,
				     root->fs_info->extent_root, 1);
701 702
		if (ret)
			ret = btrfs_commit_transaction(trans, root);
S
Sage Weil 已提交
703 704 705 706
	} else {
		ret = btrfs_commit_transaction(trans,
					       root->fs_info->extent_root);
	}
707
	if (ret)
708
		goto fail;
709 710 711 712 713

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

714 715 716
	ret = btrfs_orphan_cleanup(pending_snapshot->snap);
	if (ret)
		goto fail;
C
Christoph Hellwig 已提交
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
	/*
	 * 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;
		}
	}

747
	inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
748 749 750 751
	if (IS_ERR(inode)) {
		ret = PTR_ERR(inode);
		goto fail;
	}
752

753 754 755
	d_instantiate(dentry, inode);
	ret = 0;
fail:
756 757 758
	btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
					 &pending_snapshot->block_rsv,
					 pending_snapshot->qgroup_reserved);
759
free:
760
	kfree(pending_snapshot);
761 762
out:
	atomic_dec(&root->will_be_snapshoted);
C
Christoph Hellwig 已提交
763 764 765
	return ret;
}

766 767 768 769 770 771
/*  copy of check_sticky in fs/namei.c()
* It's inline, so penalty for filesystems that don't use sticky bit is
* minimal.
*/
static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
{
772
	kuid_t fsuid = current_fsuid();
773 774 775

	if (!(dir->i_mode & S_ISVTX))
		return 0;
776
	if (uid_eq(inode->i_uid, fsuid))
777
		return 0;
778
	if (uid_eq(dir->i_uid, fsuid))
779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802
		return 0;
	return !capable(CAP_FOWNER);
}

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

803
static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
804 805 806 807 808 809 810
{
	int error;

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

	BUG_ON(victim->d_parent->d_inode != dir);
811
	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835

	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		return error;
	if (IS_APPEND(dir))
		return -EPERM;
	if (btrfs_check_sticky(dir, victim->d_inode)||
		IS_APPEND(victim->d_inode)||
	    IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
		return -EPERM;
	if (isdir) {
		if (!S_ISDIR(victim->d_inode->i_mode))
			return -ENOTDIR;
		if (IS_ROOT(victim))
			return -EBUSY;
	} else if (S_ISDIR(victim->d_inode->i_mode))
		return -EISDIR;
	if (IS_DEADDIR(dir))
		return -ENOENT;
	if (victim->d_flags & DCACHE_NFSFS_RENAMED)
		return -EBUSY;
	return 0;
}

836 837 838 839 840 841 842 843 844 845 846 847 848 849 850
/* 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.
 */
851 852
static noinline int btrfs_mksubvol(struct path *parent,
				   char *name, int namelen,
S
Sage Weil 已提交
853
				   struct btrfs_root *snap_src,
A
Arne Jansen 已提交
854
				   u64 *async_transid, bool readonly,
855
				   struct btrfs_qgroup_inherit *inherit)
856
{
857
	struct inode *dir  = parent->dentry->d_inode;
858 859 860
	struct dentry *dentry;
	int error;

861 862 863
	error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
	if (error == -EINTR)
		return error;
864 865 866 867 868 869 870 871 872 873

	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;

874
	error = btrfs_may_create(dir, dentry);
875
	if (error)
876
		goto out_dput;
877

C
Chris Mason 已提交
878 879 880 881 882 883 884 885 886 887
	/*
	 * 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;

888 889 890 891 892
	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;

893
	if (snap_src) {
894
		error = create_snapshot(snap_src, dir, dentry, name, namelen,
A
Arne Jansen 已提交
895
					async_transid, readonly, inherit);
896
	} else {
897 898
		error = create_subvol(dir, dentry, name, namelen,
				      async_transid, inherit);
899
	}
900 901 902 903
	if (!error)
		fsnotify_mkdir(dir, dentry);
out_up_read:
	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
904 905 906
out_dput:
	dput(dentry);
out_unlock:
907
	mutex_unlock(&dir->i_mutex);
908 909 910
	return error;
}

C
Chris Mason 已提交
911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960
/*
 * When we're defragging a range, we don't want to kick it off again
 * if it is really just waiting for delalloc to send it down.
 * If we find a nice big extent or delalloc range for the bytes in the
 * file you want to defrag, we return 0 to let you know to skip this
 * part of the file
 */
static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
{
	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
	struct extent_map *em = NULL;
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
	u64 end;

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

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

/*
 * helper function to walk through a file and find extents
 * newer than a specific transid, and smaller than thresh.
 *
 * This is used by the defragging code to find new and small
 * extents
 */
static int find_new_extents(struct btrfs_root *root,
			    struct inode *inode, u64 newer_than,
			    u64 *off, int thresh)
{
	struct btrfs_path *path;
	struct btrfs_key min_key;
	struct extent_buffer *leaf;
	struct btrfs_file_extent_item *extent;
	int type;
	int ret;
961
	u64 ino = btrfs_ino(inode);
C
Chris Mason 已提交
962 963 964 965 966

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

967
	min_key.objectid = ino;
C
Chris Mason 已提交
968 969 970
	min_key.type = BTRFS_EXTENT_DATA_KEY;
	min_key.offset = *off;

971
	while (1) {
972
		path->keep_locks = 1;
973
		ret = btrfs_search_forward(root, &min_key, path, newer_than);
C
Chris Mason 已提交
974 975
		if (ret != 0)
			goto none;
976 977 978
		path->keep_locks = 0;
		btrfs_unlock_up_safe(path, 1);
process_slot:
979
		if (min_key.objectid != ino)
C
Chris Mason 已提交
980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996
			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;
		}

997 998 999 1000 1001 1002
		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
1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013
		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
1014
static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1015 1016
{
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
L
Li Zefan 已提交
1017 1018 1019
	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
	struct extent_map *em;
	u64 len = PAGE_CACHE_SIZE;
1020

L
Li Zefan 已提交
1021 1022 1023 1024
	/*
	 * hopefully we have this extent in the tree already, try without
	 * the full extent lock
	 */
1025
	read_lock(&em_tree->lock);
L
Li Zefan 已提交
1026
	em = lookup_extent_mapping(em_tree, start, len);
1027 1028
	read_unlock(&em_tree->lock);

L
Li Zefan 已提交
1029
	if (!em) {
1030 1031 1032
		struct extent_state *cached = NULL;
		u64 end = start + len - 1;

L
Li Zefan 已提交
1033
		/* get the big lock and read metadata off disk */
1034
		lock_extent_bits(io_tree, start, end, 0, &cached);
L
Li Zefan 已提交
1035
		em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1036
		unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
L
Li Zefan 已提交
1037 1038 1039 1040 1041 1042 1043

		if (IS_ERR(em))
			return NULL;
	}

	return em;
}
1044

L
Li Zefan 已提交
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054
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);
1055 1056
	if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE ||
	    (em->block_start + em->block_len == next->block_start))
L
Li Zefan 已提交
1057 1058 1059
		ret = false;

	free_extent_map(next);
1060 1061 1062
	return ret;
}

L
Li Zefan 已提交
1063
static int should_defrag_range(struct inode *inode, u64 start, int thresh,
1064 1065
			       u64 *last_len, u64 *skip, u64 *defrag_end,
			       int compress)
1066
{
L
Li Zefan 已提交
1067
	struct extent_map *em;
1068
	int ret = 1;
L
Li Zefan 已提交
1069
	bool next_mergeable = true;
1070 1071

	/*
1072
	 * make sure that once we start defragging an extent, we keep on
1073 1074 1075 1076 1077 1078 1079
	 * defragging it
	 */
	if (start < *defrag_end)
		return 1;

	*skip = 0;

L
Li Zefan 已提交
1080 1081 1082
	em = defrag_lookup_extent(inode, start);
	if (!em)
		return 0;
1083 1084

	/* this will cover holes, and inline extents */
1085
	if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1086
		ret = 0;
1087 1088 1089
		goto out;
	}

L
Li Zefan 已提交
1090
	next_mergeable = defrag_check_next_extent(inode, em);
1091 1092

	/*
L
Li Zefan 已提交
1093 1094
	 * we hit a real extent, if it is big or the next extent is not a
	 * real extent, don't bother defragging it
1095
	 */
1096
	if (!compress && (*last_len == 0 || *last_len >= thresh) &&
L
Li Zefan 已提交
1097
	    (em->len >= thresh || !next_mergeable))
1098
		ret = 0;
1099
out:
1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119
	/*
	 * 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
1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134
/*
 * 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,
1135
				    unsigned long num_pages)
C
Christoph Hellwig 已提交
1136
{
C
Chris Mason 已提交
1137 1138 1139 1140
	unsigned long file_end;
	u64 isize = i_size_read(inode);
	u64 page_start;
	u64 page_end;
1141
	u64 page_cnt;
C
Chris Mason 已提交
1142 1143 1144
	int ret;
	int i;
	int i_done;
1145
	struct btrfs_ordered_extent *ordered;
C
Chris Mason 已提交
1146
	struct extent_state *cached_state = NULL;
1147
	struct extent_io_tree *tree;
1148
	gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
C
Chris Mason 已提交
1149 1150

	file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1151 1152 1153 1154
	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
1155 1156

	ret = btrfs_delalloc_reserve_space(inode,
1157
					   page_cnt << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1158 1159 1160
	if (ret)
		return ret;
	i_done = 0;
1161
	tree = &BTRFS_I(inode)->io_tree;
C
Chris Mason 已提交
1162 1163

	/* step one, lock all the pages */
1164
	for (i = 0; i < page_cnt; i++) {
C
Chris Mason 已提交
1165
		struct page *page;
1166
again:
1167
		page = find_or_create_page(inode->i_mapping,
1168
					   start_index + i, mask);
C
Chris Mason 已提交
1169 1170 1171
		if (!page)
			break;

1172 1173 1174
		page_start = page_offset(page);
		page_end = page_start + PAGE_CACHE_SIZE - 1;
		while (1) {
1175 1176
			lock_extent_bits(tree, page_start, page_end,
					 0, &cached_state);
1177 1178
			ordered = btrfs_lookup_ordered_extent(inode,
							      page_start);
1179 1180
			unlock_extent_cached(tree, page_start, page_end,
					     &cached_state, GFP_NOFS);
1181 1182 1183 1184 1185 1186 1187
			if (!ordered)
				break;

			unlock_page(page);
			btrfs_start_ordered_extent(inode, ordered, 1);
			btrfs_put_ordered_extent(ordered);
			lock_page(page);
1188 1189 1190 1191 1192 1193 1194 1195 1196
			/*
			 * 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;
			}
1197 1198
		}

C
Chris Mason 已提交
1199 1200 1201 1202 1203 1204 1205 1206 1207 1208
		if (!PageUptodate(page)) {
			btrfs_readpage(NULL, page);
			lock_page(page);
			if (!PageUptodate(page)) {
				unlock_page(page);
				page_cache_release(page);
				ret = -EIO;
				break;
			}
		}
1209 1210 1211 1212 1213 1214 1215

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

C
Chris Mason 已提交
1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235
		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,
1236
			 page_start, page_end - 1, 0, &cached_state);
C
Chris Mason 已提交
1237 1238
	clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
			  page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1239 1240
			  EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
			  &cached_state, GFP_NOFS);
C
Chris Mason 已提交
1241

1242
	if (i_done != page_cnt) {
1243 1244 1245
		spin_lock(&BTRFS_I(inode)->lock);
		BTRFS_I(inode)->outstanding_extents++;
		spin_unlock(&BTRFS_I(inode)->lock);
C
Chris Mason 已提交
1246
		btrfs_delalloc_release_space(inode,
1247
				     (page_cnt - i_done) << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1248 1249 1250
	}


1251 1252
	set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
			  &cached_state, GFP_NOFS);
C
Chris Mason 已提交
1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271

	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]);
	}
1272
	btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1273 1274 1275 1276 1277 1278 1279 1280 1281 1282
	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
1283
	unsigned long last_index;
1284
	u64 isize = i_size_read(inode);
1285 1286 1287
	u64 last_len = 0;
	u64 skip = 0;
	u64 defrag_end = 0;
C
Chris Mason 已提交
1288
	u64 newer_off = range->start;
C
Christoph Hellwig 已提交
1289
	unsigned long i;
1290
	unsigned long ra_index = 0;
C
Christoph Hellwig 已提交
1291
	int ret;
C
Chris Mason 已提交
1292
	int defrag_count = 0;
1293
	int compress_type = BTRFS_COMPRESS_ZLIB;
C
Chris Mason 已提交
1294
	int extent_thresh = range->extent_thresh;
1295 1296
	unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
	unsigned long cluster = max_cluster;
C
Chris Mason 已提交
1297 1298 1299
	u64 new_align = ~((u64)128 * 1024 - 1);
	struct page **pages = NULL;

1300 1301 1302 1303 1304
	if (isize == 0)
		return 0;

	if (range->start >= isize)
		return -EINVAL;
1305 1306 1307 1308 1309 1310 1311

	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
1312

1313 1314
	if (extent_thresh == 0)
		extent_thresh = 256 * 1024;
1315

C
Chris Mason 已提交
1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328
	/*
	 * 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;
	}

1329
	pages = kmalloc_array(max_cluster, sizeof(struct page *),
C
Chris Mason 已提交
1330 1331 1332 1333 1334 1335 1336
			GFP_NOFS);
	if (!pages) {
		ret = -ENOMEM;
		goto out_ra;
	}

	/* find the last page to defrag */
C
Chris Mason 已提交
1337
	if (range->start + range->len > range->start) {
1338
		last_index = min_t(u64, isize - 1,
C
Chris Mason 已提交
1339 1340
			 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
	} else {
1341
		last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
C
Chris Mason 已提交
1342 1343
	}

C
Chris Mason 已提交
1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359
	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
1360
		max_to_defrag = last_index + 1;
C
Chris Mason 已提交
1361

L
Li Zefan 已提交
1362 1363 1364 1365 1366 1367 1368
	/*
	 * 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;

1369 1370 1371
	while (i <= last_index && defrag_count < max_to_defrag &&
	       (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
		PAGE_CACHE_SHIFT)) {
C
Chris Mason 已提交
1372 1373 1374 1375 1376 1377 1378
		/*
		 * make sure we stop running if someone unmounts
		 * the FS
		 */
		if (!(inode->i_sb->s_flags & MS_ACTIVE))
			break;

1379
		if (btrfs_defrag_cancelled(root->fs_info)) {
1380
			printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1381 1382 1383 1384
			ret = -EAGAIN;
			break;
		}

1385
		if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
L
Li Zefan 已提交
1386
					 extent_thresh, &last_len, &skip,
1387 1388
					 &defrag_end, range->flags &
					 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1389 1390 1391 1392 1393 1394 1395 1396 1397
			unsigned long next;
			/*
			 * the should_defrag function tells us how much to skip
			 * bump our counter by the suggested amount
			 */
			next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
			i = max(i + 1, next);
			continue;
		}
1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412

		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;
		}
1413

1414
		mutex_lock(&inode->i_mutex);
1415 1416
		if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
			BTRFS_I(inode)->force_compress = compress_type;
1417
		ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1418 1419
		if (ret < 0) {
			mutex_unlock(&inode->i_mutex);
C
Chris Mason 已提交
1420
			goto out_ra;
1421
		}
C
Chris Mason 已提交
1422 1423

		defrag_count += ret;
1424
		balance_dirty_pages_ratelimited(inode->i_mapping);
1425
		mutex_unlock(&inode->i_mutex);
C
Chris Mason 已提交
1426 1427 1428 1429 1430

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

1431 1432 1433
			if (ret > 0)
				i += ret;

C
Chris Mason 已提交
1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444
			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
1445
			}
C
Chris Mason 已提交
1446
		} else {
1447
			if (ret > 0) {
L
Li Zefan 已提交
1448
				i += ret;
1449 1450
				last_len += ret << PAGE_CACHE_SHIFT;
			} else {
L
Li Zefan 已提交
1451
				i++;
1452 1453
				last_len = 0;
			}
C
Christoph Hellwig 已提交
1454 1455 1456
		}
	}

1457
	if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
C
Chris Mason 已提交
1458
		filemap_flush(inode->i_mapping);
1459 1460 1461 1462
		if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
			     &BTRFS_I(inode)->runtime_flags))
			filemap_flush(inode->i_mapping);
	}
C
Chris Mason 已提交
1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478

	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);
	}

1479
	if (range->compress_type == BTRFS_COMPRESS_LZO) {
1480
		btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1481 1482
	}

1483
	ret = defrag_count;
1484

C
Chris Mason 已提交
1485
out_ra:
1486 1487 1488 1489 1490
	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
1491 1492 1493
	if (!file)
		kfree(ra);
	kfree(pages);
1494
	return ret;
C
Christoph Hellwig 已提交
1495 1496
}

1497
static noinline int btrfs_ioctl_resize(struct file *file,
1498
					void __user *arg)
C
Christoph Hellwig 已提交
1499 1500 1501 1502
{
	u64 new_size;
	u64 old_size;
	u64 devid = 1;
A
Al Viro 已提交
1503
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
C
Christoph Hellwig 已提交
1504 1505 1506 1507
	struct btrfs_ioctl_vol_args *vol_args;
	struct btrfs_trans_handle *trans;
	struct btrfs_device *device = NULL;
	char *sizestr;
1508
	char *retptr;
C
Christoph Hellwig 已提交
1509 1510 1511 1512
	char *devstr = NULL;
	int ret = 0;
	int mod = 0;

1513 1514 1515
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

1516 1517 1518 1519
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

1520 1521
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
1522
		mnt_drop_write_file(file);
1523
		return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1524 1525
	}

1526
	mutex_lock(&root->fs_info->volume_mutex);
L
Li Zefan 已提交
1527
	vol_args = memdup_user(arg, sizeof(*vol_args));
1528 1529 1530 1531
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
1532 1533

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
1534 1535 1536 1537 1538 1539 1540

	sizestr = vol_args->name;
	devstr = strchr(sizestr, ':');
	if (devstr) {
		sizestr = devstr + 1;
		*devstr = '\0';
		devstr = vol_args->name;
1541 1542 1543
		ret = kstrtoull(devstr, 10, &devid);
		if (ret)
			goto out_free;
1544 1545 1546 1547
		if (!devid) {
			ret = -EINVAL;
			goto out_free;
		}
1548
		btrfs_info(root->fs_info, "resizing devid %llu", devid);
C
Christoph Hellwig 已提交
1549
	}
M
Miao Xie 已提交
1550

1551
	device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
C
Christoph Hellwig 已提交
1552
	if (!device) {
1553
		btrfs_info(root->fs_info, "resizer unable to find device %llu",
1554
		       devid);
1555
		ret = -ENODEV;
1556
		goto out_free;
C
Christoph Hellwig 已提交
1557
	}
M
Miao Xie 已提交
1558 1559

	if (!device->writeable) {
1560 1561
		btrfs_info(root->fs_info,
			   "resizer unable to apply on readonly device %llu",
1562
		       devid);
1563
		ret = -EPERM;
L
Liu Bo 已提交
1564 1565 1566
		goto out_free;
	}

C
Christoph Hellwig 已提交
1567 1568 1569 1570 1571 1572 1573 1574 1575 1576
	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++;
		}
1577 1578
		new_size = memparse(sizestr, &retptr);
		if (*retptr != '\0' || new_size == 0) {
C
Christoph Hellwig 已提交
1579
			ret = -EINVAL;
1580
			goto out_free;
C
Christoph Hellwig 已提交
1581 1582 1583
		}
	}

1584
	if (device->is_tgtdev_for_dev_replace) {
1585
		ret = -EPERM;
1586 1587 1588
		goto out_free;
	}

C
Christoph Hellwig 已提交
1589 1590 1591 1592 1593
	old_size = device->total_bytes;

	if (mod < 0) {
		if (new_size > old_size) {
			ret = -EINVAL;
1594
			goto out_free;
C
Christoph Hellwig 已提交
1595 1596 1597
		}
		new_size = old_size - new_size;
	} else if (mod > 0) {
1598
		if (new_size > ULLONG_MAX - old_size) {
1599
			ret = -ERANGE;
1600 1601
			goto out_free;
		}
C
Christoph Hellwig 已提交
1602 1603 1604 1605 1606
		new_size = old_size + new_size;
	}

	if (new_size < 256 * 1024 * 1024) {
		ret = -EINVAL;
1607
		goto out_free;
C
Christoph Hellwig 已提交
1608 1609 1610
	}
	if (new_size > device->bdev->bd_inode->i_size) {
		ret = -EFBIG;
1611
		goto out_free;
C
Christoph Hellwig 已提交
1612 1613 1614 1615 1616
	}

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

1617
	printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1618
		      rcu_str_deref(device->name), new_size);
C
Christoph Hellwig 已提交
1619 1620

	if (new_size > old_size) {
1621
		trans = btrfs_start_transaction(root, 0);
1622 1623
		if (IS_ERR(trans)) {
			ret = PTR_ERR(trans);
1624
			goto out_free;
1625
		}
C
Christoph Hellwig 已提交
1626 1627
		ret = btrfs_grow_device(trans, device, new_size);
		btrfs_commit_transaction(trans, root);
1628
	} else if (new_size < old_size) {
C
Christoph Hellwig 已提交
1629
		ret = btrfs_shrink_device(device, new_size);
1630
	} /* equal, nothing need to do */
C
Christoph Hellwig 已提交
1631

1632
out_free:
C
Christoph Hellwig 已提交
1633
	kfree(vol_args);
1634 1635
out:
	mutex_unlock(&root->fs_info->volume_mutex);
1636
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1637
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
1638 1639 1640
	return ret;
}

S
Sage Weil 已提交
1641
static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
A
Arne Jansen 已提交
1642 1643
				char *name, unsigned long fd, int subvol,
				u64 *transid, bool readonly,
1644
				struct btrfs_qgroup_inherit *inherit)
C
Christoph Hellwig 已提交
1645 1646
{
	int namelen;
1647
	int ret = 0;
C
Christoph Hellwig 已提交
1648

1649 1650 1651 1652
	ret = mnt_want_write_file(file);
	if (ret)
		goto out;

S
Sage Weil 已提交
1653 1654
	namelen = strlen(name);
	if (strchr(name, '/')) {
C
Christoph Hellwig 已提交
1655
		ret = -EINVAL;
1656
		goto out_drop_write;
C
Christoph Hellwig 已提交
1657 1658
	}

1659 1660 1661
	if (name[0] == '.' &&
	   (namelen == 1 || (name[1] == '.' && namelen == 2))) {
		ret = -EEXIST;
1662
		goto out_drop_write;
1663 1664
	}

1665
	if (subvol) {
S
Sage Weil 已提交
1666
		ret = btrfs_mksubvol(&file->f_path, name, namelen,
A
Arne Jansen 已提交
1667
				     NULL, transid, readonly, inherit);
1668
	} else {
1669
		struct fd src = fdget(fd);
1670
		struct inode *src_inode;
1671
		if (!src.file) {
1672
			ret = -EINVAL;
1673
			goto out_drop_write;
1674 1675
		}

A
Al Viro 已提交
1676 1677
		src_inode = file_inode(src.file);
		if (src_inode->i_sb != file_inode(file)->i_sb) {
1678 1679
			btrfs_info(BTRFS_I(src_inode)->root->fs_info,
				   "Snapshot src from another FS");
1680
			ret = -EXDEV;
1681 1682 1683 1684 1685 1686
		} else if (!inode_owner_or_capable(src_inode)) {
			/*
			 * Subvolume creation is not restricted, but snapshots
			 * are limited to own subvolumes only
			 */
			ret = -EPERM;
1687 1688 1689 1690
		} else {
			ret = btrfs_mksubvol(&file->f_path, name, namelen,
					     BTRFS_I(src_inode)->root,
					     transid, readonly, inherit);
1691
		}
1692
		fdput(src);
1693
	}
1694 1695
out_drop_write:
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
1696
out:
S
Sage Weil 已提交
1697 1698 1699 1700
	return ret;
}

static noinline int btrfs_ioctl_snap_create(struct file *file,
1701
					    void __user *arg, int subvol)
S
Sage Weil 已提交
1702
{
1703
	struct btrfs_ioctl_vol_args *vol_args;
S
Sage Weil 已提交
1704 1705
	int ret;

1706 1707 1708 1709
	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
1710

1711
	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
L
Li Zefan 已提交
1712
					      vol_args->fd, subvol,
A
Arne Jansen 已提交
1713
					      NULL, false, NULL);
1714

1715 1716 1717
	kfree(vol_args);
	return ret;
}
1718

1719 1720 1721 1722 1723 1724 1725
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
1726
	bool readonly = false;
A
Arne Jansen 已提交
1727
	struct btrfs_qgroup_inherit *inherit = NULL;
1728

1729 1730 1731 1732
	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';
1733

L
Li Zefan 已提交
1734
	if (vol_args->flags &
A
Arne Jansen 已提交
1735 1736
	    ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
	      BTRFS_SUBVOL_QGROUP_INHERIT)) {
L
Li Zefan 已提交
1737
		ret = -EOPNOTSUPP;
1738
		goto out;
S
Sage Weil 已提交
1739
	}
1740 1741 1742

	if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
		ptr = &transid;
L
Li Zefan 已提交
1743 1744
	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
		readonly = true;
A
Arne Jansen 已提交
1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755
	if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
		if (vol_args->size > PAGE_CACHE_SIZE) {
			ret = -EINVAL;
			goto out;
		}
		inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
		if (IS_ERR(inherit)) {
			ret = PTR_ERR(inherit);
			goto out;
		}
	}
1756 1757

	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
A
Arne Jansen 已提交
1758
					      vol_args->fd, subvol, ptr,
1759
					      readonly, inherit);
1760 1761 1762 1763 1764 1765

	if (ret == 0 && ptr &&
	    copy_to_user(arg +
			 offsetof(struct btrfs_ioctl_vol_args_v2,
				  transid), ptr, sizeof(*ptr)))
		ret = -EFAULT;
1766
out:
C
Christoph Hellwig 已提交
1767
	kfree(vol_args);
A
Arne Jansen 已提交
1768
	kfree(inherit);
C
Christoph Hellwig 已提交
1769 1770 1771
	return ret;
}

1772 1773 1774
static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
						void __user *arg)
{
A
Al Viro 已提交
1775
	struct inode *inode = file_inode(file);
1776 1777 1778 1779
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret = 0;
	u64 flags = 0;

L
Li Zefan 已提交
1780
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796
		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
1797
	struct inode *inode = file_inode(file);
1798 1799 1800 1801 1802 1803
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
	u64 root_flags;
	u64 flags;
	int ret = 0;

1804 1805 1806
	if (!inode_owner_or_capable(inode))
		return -EPERM;

1807 1808 1809
	ret = mnt_want_write_file(file);
	if (ret)
		goto out;
1810

1811 1812 1813 1814
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
		ret = -EINVAL;
		goto out_drop_write;
	}
1815

1816 1817 1818 1819
	if (copy_from_user(&flags, arg, sizeof(flags))) {
		ret = -EFAULT;
		goto out_drop_write;
	}
1820

1821 1822 1823 1824
	if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
		ret = -EINVAL;
		goto out_drop_write;
	}
1825

1826 1827 1828 1829
	if (flags & ~BTRFS_SUBVOL_RDONLY) {
		ret = -EOPNOTSUPP;
		goto out_drop_write;
	}
1830 1831 1832 1833 1834

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

	/* nothing to do */
	if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1835
		goto out_drop_sem;
1836 1837

	root_flags = btrfs_root_flags(&root->root_item);
1838
	if (flags & BTRFS_SUBVOL_RDONLY) {
1839 1840
		btrfs_set_root_flags(&root->root_item,
				     root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1841 1842 1843 1844 1845 1846 1847 1848
	} 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,
1849
				     root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1850 1851 1852 1853 1854 1855 1856 1857 1858 1859
			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;
		}
	}
1860 1861 1862 1863 1864 1865 1866

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

1867
	ret = btrfs_update_root(trans, root->fs_info->tree_root,
1868 1869 1870 1871 1872 1873
				&root->root_key, &root->root_item);

	btrfs_commit_transaction(trans, root);
out_reset:
	if (ret)
		btrfs_set_root_flags(&root->root_item, root_flags);
1874
out_drop_sem:
1875
	up_write(&root->fs_info->subvol_sem);
1876 1877 1878
out_drop_write:
	mnt_drop_write_file(file);
out:
1879 1880 1881
	return ret;
}

1882 1883 1884 1885 1886 1887
/*
 * helper to check if the subvolume references other subvolumes
 */
static noinline int may_destroy_subvol(struct btrfs_root *root)
{
	struct btrfs_path *path;
1888
	struct btrfs_dir_item *di;
1889
	struct btrfs_key key;
1890
	u64 dir_id;
1891 1892 1893 1894 1895 1896
	int ret;

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

1897 1898 1899 1900 1901 1902 1903
	/* 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) {
1904 1905 1906
			ret = -EPERM;
			btrfs_err(root->fs_info, "deleting default subvolume "
				  "%llu is not allowed", key.objectid);
1907 1908 1909 1910 1911
			goto out;
		}
		btrfs_release_path(path);
	}

1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934
	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;
}

1935 1936 1937
static noinline int key_in_sk(struct btrfs_key *key,
			      struct btrfs_ioctl_search_key *sk)
{
1938 1939 1940 1941 1942 1943 1944 1945 1946
	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)
1947
		return 0;
1948 1949 1950 1951 1952 1953 1954

	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)
1955 1956 1957 1958 1959 1960 1961 1962
		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,
1963
			       size_t *buf_size,
1964
			       char __user *ubuf,
1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991
			       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);

1992 1993 1994 1995
		btrfs_item_key_to_cpu(leaf, key, i);
		if (!key_in_sk(key, sk))
			continue;

1996
		if (sizeof(sh) + item_len > *buf_size) {
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
			if (*num_found) {
				ret = 1;
				goto out;
			}

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

2007
			*buf_size = sizeof(sh) + item_len;
2008
			item_len = 0;
2009 2010
			ret = -EOVERFLOW;
		}
2011

2012
		if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2013
			ret = 1;
2014
			goto out;
2015 2016 2017 2018 2019 2020 2021 2022 2023
		}

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

		/* copy search result header */
2024 2025 2026 2027 2028
		if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
			ret = -EFAULT;
			goto out;
		}

2029 2030 2031
		*sk_offset += sizeof(sh);

		if (item_len) {
2032
			char __user *up = ubuf + *sk_offset;
2033
			/* copy the item */
2034 2035 2036 2037 2038 2039
			if (read_extent_buffer_to_user(leaf, up,
						       item_off, item_len)) {
				ret = -EFAULT;
				goto out;
			}

2040 2041
			*sk_offset += item_len;
		}
2042
		(*num_found)++;
2043

2044 2045 2046
		if (ret) /* -EOVERFLOW from above */
			goto out;

2047 2048 2049 2050
		if (*num_found >= sk->nr_items) {
			ret = 1;
			goto out;
		}
2051 2052
	}
advance_key:
2053 2054
	ret = 0;
	if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2055
		key->offset++;
2056 2057
	else if (key->type < (u8)-1 && key->type < sk->max_type) {
		key->offset = 0;
2058
		key->type++;
2059 2060 2061
	} else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
		key->offset = 0;
		key->type = 0;
2062
		key->objectid++;
2063 2064
	} else
		ret = 1;
2065
out:
2066 2067 2068 2069 2070 2071 2072 2073 2074
	/*
	 *  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
	 */
2075 2076 2077 2078
	return ret;
}

static noinline int search_ioctl(struct inode *inode,
2079
				 struct btrfs_ioctl_search_key *sk,
2080
				 size_t *buf_size,
2081
				 char __user *ubuf)
2082 2083 2084 2085 2086 2087 2088 2089 2090
{
	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;

2091 2092
	if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
		*buf_size = sizeof(struct btrfs_ioctl_search_header);
2093
		return -EOVERFLOW;
2094
	}
2095

2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108
	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)) {
2109
			printk(KERN_ERR "BTRFS: could not find root %llu\n",
2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121
			       sk->tree_id);
			btrfs_free_path(path);
			return -ENOENT;
		}
	}

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

	path->keep_locks = 1;

2122
	while (1) {
2123
		ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2124 2125 2126 2127 2128
		if (ret != 0) {
			if (ret > 0)
				ret = 0;
			goto err;
		}
2129
		ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2130
				 &sk_offset, &num_found);
2131
		btrfs_release_path(path);
2132
		if (ret)
2133 2134 2135
			break;

	}
2136 2137
	if (ret > 0)
		ret = 0;
2138 2139 2140 2141 2142 2143 2144 2145 2146
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)
{
2147 2148
	struct btrfs_ioctl_search_args __user *uargs;
	struct btrfs_ioctl_search_key sk;
2149 2150 2151
	struct inode *inode;
	int ret;
	size_t buf_size;
2152 2153 2154 2155

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

2156 2157 2158 2159
	uargs = (struct btrfs_ioctl_search_args __user *)argp;

	if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
		return -EFAULT;
2160

2161
	buf_size = sizeof(uargs->buf);
2162

A
Al Viro 已提交
2163
	inode = file_inode(file);
2164
	ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2165 2166 2167 2168 2169 2170 2171 2172

	/*
	 * 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;

2173
	if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2174 2175 2176 2177
		ret = -EFAULT;
	return ret;
}

G
Gerhard Heift 已提交
2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216
static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
					       void __user *argp)
{
	struct btrfs_ioctl_search_args_v2 __user *uarg;
	struct btrfs_ioctl_search_args_v2 args;
	struct inode *inode;
	int ret;
	size_t buf_size;
	const size_t buf_limit = 16 * 1024 * 1024;

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

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

	buf_size = args.buf_size;

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

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

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

	return ret;
}

2217
/*
2218 2219 2220
 * Search INODE_REFs to identify path name of 'dirid' directory
 * in a 'tree_id' tree. and sets path name to 'name'.
 */
2221 2222 2223 2224 2225
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;
2226
	char *ptr;
2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243
	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;

2244
	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2245 2246 2247 2248 2249 2250

	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)) {
2251
		printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2252 2253
		ret = -ENOENT;
		goto out;
2254 2255 2256 2257
	}

	key.objectid = dirid;
	key.type = BTRFS_INODE_REF_KEY;
2258
	key.offset = (u64)-1;
2259

2260
	while (1) {
2261 2262 2263
		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
		if (ret < 0)
			goto out;
2264 2265 2266 2267 2268 2269 2270 2271 2272 2273
		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;
			}
		}
2274 2275 2276 2277 2278 2279 2280 2281 2282

		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;
2283 2284
		if (ptr < name) {
			ret = -ENAMETOOLONG;
2285
			goto out;
2286
		}
2287 2288

		*(ptr + len) = '/';
2289
		read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2290 2291 2292 2293

		if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
			break;

2294
		btrfs_release_path(path);
2295
		key.objectid = key.offset;
2296
		key.offset = (u64)-1;
2297 2298
		dirid = key.objectid;
	}
2299
	memmove(name, ptr, total_len);
2300
	name[total_len] = '\0';
2301 2302 2303
	ret = 0;
out:
	btrfs_free_path(path);
2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316
	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
2317 2318 2319
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
2320

A
Al Viro 已提交
2321
	inode = file_inode(file);
2322

2323 2324 2325
	if (args->treeid == 0)
		args->treeid = BTRFS_I(inode)->root->root_key.objectid;

2326 2327 2328 2329 2330 2331 2332 2333
	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);
2334 2335 2336
	return ret;
}

2337 2338 2339
static noinline int btrfs_ioctl_snap_destroy(struct file *file,
					     void __user *arg)
{
A
Al Viro 已提交
2340
	struct dentry *parent = file->f_path.dentry;
2341 2342 2343 2344 2345 2346 2347
	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;
2348
	struct btrfs_block_rsv block_rsv;
2349
	u64 root_flags;
2350
	u64 qgroup_reserved;
2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366
	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;
	}

2367
	err = mnt_want_write_file(file);
2368 2369 2370
	if (err)
		goto out;

2371

2372 2373
	err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
	if (err == -EINTR)
2374
		goto out_drop_write;
2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386
	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;
2387
	dest = BTRFS_I(inode)->root;
2388
	if (!capable(CAP_SYS_ADMIN)) {
2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421
		/*
		 * 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;
	}

2422 2423 2424 2425 2426
	/* 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
2427
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2428 2429 2430 2431 2432
		err = -EINVAL;
		goto out_dput;
	}

	mutex_lock(&inode->i_mutex);
2433 2434 2435 2436 2437 2438 2439

	/*
	 * 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);
2440 2441 2442
	root_flags = btrfs_root_flags(&dest->root_item);
	if (dest->send_in_progress == 0) {
		btrfs_set_root_flags(&dest->root_item,
2443 2444 2445 2446 2447 2448
				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",
2449
			dest->root_key.objectid);
2450 2451 2452 2453
		err = -EPERM;
		goto out_dput;
	}

2454 2455 2456 2457 2458 2459 2460 2461 2462 2463
	err = d_invalidate(dentry);
	if (err)
		goto out_unlock;

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

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

2464 2465 2466 2467 2468 2469
	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,
2470
					       5, &qgroup_reserved, true);
2471 2472 2473
	if (err)
		goto out_up_write;

2474 2475 2476
	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		err = PTR_ERR(trans);
2477
		goto out_release;
2478
	}
2479 2480
	trans->block_rsv = &block_rsv;
	trans->bytes_reserved = block_rsv.size;
2481

2482 2483 2484 2485
	ret = btrfs_unlink_subvol(trans, root, dir,
				dest->root_key.objectid,
				dentry->d_name.name,
				dentry->d_name.len);
2486 2487 2488 2489 2490
	if (ret) {
		err = ret;
		btrfs_abort_transaction(trans, root, ret);
		goto out_end_trans;
	}
2491 2492 2493 2494 2495 2496 2497 2498

	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);

2499
	if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2500 2501 2502
		ret = btrfs_insert_orphan_item(trans,
					root->fs_info->tree_root,
					dest->root_key.objectid);
2503 2504 2505 2506 2507
		if (ret) {
			btrfs_abort_transaction(trans, root, ret);
			err = ret;
			goto out_end_trans;
		}
2508
	}
2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529

	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;
		}
	}

2530
out_end_trans:
2531 2532
	trans->block_rsv = NULL;
	trans->bytes_reserved = 0;
S
Sage Weil 已提交
2533
	ret = btrfs_end_transaction(trans, root);
2534 2535
	if (ret && !err)
		err = ret;
2536
	inode->i_flags |= S_DEAD;
2537 2538
out_release:
	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2539 2540 2541
out_up_write:
	up_write(&root->fs_info->subvol_sem);
out_unlock:
2542 2543
	if (err) {
		spin_lock(&dest->root_item_lock);
2544 2545
		root_flags = btrfs_root_flags(&dest->root_item);
		btrfs_set_root_flags(&dest->root_item,
2546 2547 2548
				root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
		spin_unlock(&dest->root_item_lock);
	}
2549 2550
	mutex_unlock(&inode->i_mutex);
	if (!err) {
2551
		shrink_dcache_sb(root->fs_info->sb);
2552 2553
		btrfs_invalidate_inodes(dest);
		d_delete(dentry);
2554
		ASSERT(dest->send_in_progress == 0);
2555 2556 2557 2558 2559 2560

		/* the last ref */
		if (dest->cache_inode) {
			iput(dest->cache_inode);
			dest->cache_inode = NULL;
		}
2561 2562 2563 2564 2565
	}
out_dput:
	dput(dentry);
out_unlock_dir:
	mutex_unlock(&dir->i_mutex);
2566
out_drop_write:
A
Al Viro 已提交
2567
	mnt_drop_write_file(file);
2568 2569 2570 2571 2572
out:
	kfree(vol_args);
	return err;
}

C
Chris Mason 已提交
2573
static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
C
Christoph Hellwig 已提交
2574
{
A
Al Viro 已提交
2575
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
2576
	struct btrfs_root *root = BTRFS_I(inode)->root;
C
Chris Mason 已提交
2577
	struct btrfs_ioctl_defrag_range_args *range;
Y
Yan Zheng 已提交
2578 2579
	int ret;

2580 2581 2582
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
L
Li Zefan 已提交
2583

2584 2585 2586
	if (btrfs_root_readonly(root)) {
		ret = -EROFS;
		goto out;
2587
	}
C
Christoph Hellwig 已提交
2588 2589 2590

	switch (inode->i_mode & S_IFMT) {
	case S_IFDIR:
2591 2592 2593 2594
		if (!capable(CAP_SYS_ADMIN)) {
			ret = -EPERM;
			goto out;
		}
2595
		ret = btrfs_defrag_root(root);
2596 2597
		if (ret)
			goto out;
2598
		ret = btrfs_defrag_root(root->fs_info->extent_root);
C
Christoph Hellwig 已提交
2599 2600
		break;
	case S_IFREG:
2601 2602 2603 2604
		if (!(file->f_mode & FMODE_WRITE)) {
			ret = -EINVAL;
			goto out;
		}
C
Chris Mason 已提交
2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616

		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);
2617
				goto out;
C
Chris Mason 已提交
2618 2619 2620 2621 2622 2623 2624 2625 2626 2627
			}
			/* 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
2628
		ret = btrfs_defrag_file(file_inode(file), file,
C
Chris Mason 已提交
2629 2630 2631
					range, 0, 0);
		if (ret > 0)
			ret = 0;
C
Chris Mason 已提交
2632
		kfree(range);
C
Christoph Hellwig 已提交
2633
		break;
2634 2635
	default:
		ret = -EINVAL;
C
Christoph Hellwig 已提交
2636
	}
2637
out:
2638
	mnt_drop_write_file(file);
2639
	return ret;
C
Christoph Hellwig 已提交
2640 2641
}

2642
static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
2643 2644 2645 2646
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

2647 2648 2649
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2650 2651
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
2652
		return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2653 2654
	}

2655
	mutex_lock(&root->fs_info->volume_mutex);
L
Li Zefan 已提交
2656
	vol_args = memdup_user(arg, sizeof(*vol_args));
2657 2658 2659 2660
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
C
Christoph Hellwig 已提交
2661

2662
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
2663 2664 2665
	ret = btrfs_init_new_device(root, vol_args->name);

	kfree(vol_args);
2666 2667
out:
	mutex_unlock(&root->fs_info->volume_mutex);
2668
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
C
Christoph Hellwig 已提交
2669 2670 2671
	return ret;
}

2672
static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
C
Christoph Hellwig 已提交
2673
{
A
Al Viro 已提交
2674
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
C
Christoph Hellwig 已提交
2675 2676 2677
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

2678 2679 2680
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2681 2682 2683
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
Y
Yan Zheng 已提交
2684

L
Li Zefan 已提交
2685
	vol_args = memdup_user(arg, sizeof(*vol_args));
2686 2687 2688 2689
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
C
Christoph Hellwig 已提交
2690

2691
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
2692

2693 2694 2695 2696 2697 2698 2699 2700
	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);
2701
	mutex_unlock(&root->fs_info->volume_mutex);
2702
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2703 2704 2705

out:
	kfree(vol_args);
2706
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
2707 2708 2709
	return ret;
}

J
Jan Schmidt 已提交
2710 2711
static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
{
2712
	struct btrfs_ioctl_fs_info_args *fi_args;
J
Jan Schmidt 已提交
2713 2714 2715
	struct btrfs_device *device;
	struct btrfs_device *next;
	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2716
	int ret = 0;
J
Jan Schmidt 已提交
2717

2718 2719 2720 2721
	fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
	if (!fi_args)
		return -ENOMEM;

2722
	mutex_lock(&fs_devices->device_list_mutex);
2723 2724
	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
2725 2726

	list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2727 2728
		if (device->devid > fi_args->max_id)
			fi_args->max_id = device->devid;
J
Jan Schmidt 已提交
2729 2730 2731
	}
	mutex_unlock(&fs_devices->device_list_mutex);

2732 2733 2734 2735
	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;

2736 2737
	if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
		ret = -EFAULT;
J
Jan Schmidt 已提交
2738

2739 2740
	kfree(fi_args);
	return ret;
J
Jan Schmidt 已提交
2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754
}

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);

2755
	if (!btrfs_is_empty_uuid(di_args->uuid))
J
Jan Schmidt 已提交
2756 2757 2758
		s_uuid = di_args->uuid;

	mutex_lock(&fs_devices->device_list_mutex);
2759
	dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
J
Jan Schmidt 已提交
2760 2761 2762 2763 2764 2765 2766 2767 2768 2769

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

	di_args->devid = dev->devid;
	di_args->bytes_used = dev->bytes_used;
	di_args->total_bytes = dev->total_bytes;
	memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2770
	if (dev->name) {
2771 2772 2773 2774 2775 2776
		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();
2777 2778
		di_args->path[sizeof(di_args->path) - 1] = 0;
	} else {
2779
		di_args->path[0] = '\0';
2780
	}
J
Jan Schmidt 已提交
2781 2782

out:
2783
	mutex_unlock(&fs_devices->device_list_mutex);
J
Jan Schmidt 已提交
2784 2785 2786 2787 2788 2789 2790
	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
2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818
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;
}

2819 2820 2821 2822 2823 2824 2825 2826 2827
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);
2828 2829 2830
		if ((!ordered ||
		     ordered->file_offset + ordered->len <= off ||
		     ordered->file_offset >= off + len) &&
2831
		    !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2832 2833 2834
				    off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
			if (ordered)
				btrfs_put_ordered_extent(ordered);
2835
			break;
2836
		}
2837 2838 2839 2840 2841 2842 2843
		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
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 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970
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,
2971
			struct btrfs_ioctl_same_args __user *argp)
M
Mark Fasheh 已提交
2972
{
2973 2974
	struct btrfs_ioctl_same_args *same;
	struct btrfs_ioctl_same_extent_info *info;
2975
	struct inode *src = file_inode(file);
M
Mark Fasheh 已提交
2976 2977 2978 2979
	u64 off;
	u64 len;
	int i;
	int ret;
2980
	unsigned long size;
M
Mark Fasheh 已提交
2981 2982
	u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
	bool is_admin = capable(CAP_SYS_ADMIN);
2983
	u16 count;
M
Mark Fasheh 已提交
2984 2985 2986 2987 2988 2989 2990 2991

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

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

2992
	if (get_user(count, &argp->dest_count)) {
M
Mark Fasheh 已提交
2993 2994 2995 2996
		ret = -EFAULT;
		goto out;
	}

2997
	size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2998

2999
	same = memdup_user(argp, size);
3000

3001 3002
	if (IS_ERR(same)) {
		ret = PTR_ERR(same);
3003 3004 3005 3006 3007
		goto out;
	}

	off = same->logical_offset;
	len = same->length;
M
Mark Fasheh 已提交
3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034

	/*
	 * 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;

3035
	/* pre-format output fields to sane values */
3036
	for (i = 0; i < count; i++) {
3037 3038 3039
		same->info[i].bytes_deduped = 0ULL;
		same->info[i].status = 0;
	}
M
Mark Fasheh 已提交
3040

3041 3042 3043 3044
	for (i = 0, info = same->info; i < count; i++, info++) {
		struct inode *dst;
		struct fd dst_file = fdget(info->fd);
		if (!dst_file.file) {
3045
			info->status = -EBADF;
3046
			continue;
M
Mark Fasheh 已提交
3047
		}
3048
		dst = file_inode(dst_file.file);
M
Mark Fasheh 已提交
3049

3050
		if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3051
			info->status = -EINVAL;
3052 3053 3054
		} else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
			info->status = -EXDEV;
		} else if (S_ISDIR(dst->i_mode)) {
3055
			info->status = -EISDIR;
3056
		} else if (!S_ISREG(dst->i_mode)) {
3057
			info->status = -EACCES;
3058 3059 3060 3061 3062
		} 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
3063
		}
3064
		fdput(dst_file);
M
Mark Fasheh 已提交
3065 3066
	}

3067 3068 3069 3070
	ret = copy_to_user(argp, same, size);
	if (ret)
		ret = -EFAULT;

M
Mark Fasheh 已提交
3071 3072 3073 3074 3075
out:
	mnt_drop_write_file(file);
	return ret;
}

J
Josef Bacik 已提交
3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110
/* 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;
}

3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141
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;
}

3142 3143 3144 3145 3146 3147 3148 3149 3150 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 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195
static void clone_update_extent_map(struct inode *inode,
				    const struct btrfs_trans_handle *trans,
				    const struct btrfs_path *path,
				    struct btrfs_file_extent_item *fi,
				    const u64 hole_offset,
				    const u64 hole_len)
{
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
	struct extent_map *em;
	int ret;

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

	if (fi) {
		btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
		em->generation = -1;
		if (btrfs_file_extent_type(path->nodes[0], fi) ==
		    BTRFS_FILE_EXTENT_INLINE)
			set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
				&BTRFS_I(inode)->runtime_flags);
	} else {
		em->start = hole_offset;
		em->len = hole_len;
		em->ram_bytes = em->len;
		em->orig_start = hole_offset;
		em->block_start = EXTENT_MAP_HOLE;
		em->block_len = 0;
		em->orig_block_len = 0;
		em->compress_type = BTRFS_COMPRESS_NONE;
		em->generation = trans->transid;
	}

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

	if (unlikely(ret))
		set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
			&BTRFS_I(inode)->runtime_flags);
}

3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207
/**
 * 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,
3208 3209
		       const u64 off, const u64 olen, const u64 olen_aligned,
		       const u64 destoff)
C
Christoph Hellwig 已提交
3210 3211
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
3212
	struct btrfs_path *path = NULL;
C
Christoph Hellwig 已提交
3213
	struct extent_buffer *leaf;
3214 3215
	struct btrfs_trans_handle *trans;
	char *buf = NULL;
Y
Yan Zheng 已提交
3216
	struct btrfs_key key;
C
Christoph Hellwig 已提交
3217 3218
	u32 nritems;
	int slot;
Y
Yan Zheng 已提交
3219
	int ret;
J
Josef Bacik 已提交
3220
	int no_quota;
3221
	const u64 len = olen_aligned;
J
Josef Bacik 已提交
3222
	u64 last_disko = 0;
3223
	u64 last_dest_end = destoff;
Y
Yan Zheng 已提交
3224 3225 3226 3227

	ret = -ENOMEM;
	buf = vmalloc(btrfs_level_size(root, 0));
	if (!buf)
3228
		return ret;
Y
Yan Zheng 已提交
3229 3230 3231 3232

	path = btrfs_alloc_path();
	if (!path) {
		vfree(buf);
3233
		return ret;
3234 3235
	}

3236
	path->reada = 2;
3237
	/* clone data */
L
Li Zefan 已提交
3238
	key.objectid = btrfs_ino(src);
Y
Yan Zheng 已提交
3239
	key.type = BTRFS_EXTENT_DATA_KEY;
3240
	key.offset = off;
C
Christoph Hellwig 已提交
3241 3242 3243 3244 3245 3246

	while (1) {
		/*
		 * note the key will change type as we walk through the
		 * tree.
		 */
3247
		path->leave_spinning = 1;
3248 3249
		ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
				0, 0);
C
Christoph Hellwig 已提交
3250 3251
		if (ret < 0)
			goto out;
3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262
		/*
		 * 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
3263

Y
Yan Zheng 已提交
3264
		nritems = btrfs_header_nritems(path->nodes[0]);
3265
process_slot:
J
Josef Bacik 已提交
3266
		no_quota = 1;
Y
Yan Zheng 已提交
3267
		if (path->slots[0] >= nritems) {
3268
			ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
C
Christoph Hellwig 已提交
3269 3270 3271 3272
			if (ret < 0)
				goto out;
			if (ret > 0)
				break;
Y
Yan Zheng 已提交
3273
			nritems = btrfs_header_nritems(path->nodes[0]);
C
Christoph Hellwig 已提交
3274 3275 3276 3277
		}
		leaf = path->nodes[0];
		slot = path->slots[0];

Y
Yan Zheng 已提交
3278
		btrfs_item_key_to_cpu(leaf, &key, slot);
3279
		if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
L
Li Zefan 已提交
3280
		    key.objectid != btrfs_ino(src))
C
Christoph Hellwig 已提交
3281 3282
			break;

3283 3284 3285
		if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
			struct btrfs_file_extent_item *extent;
			int type;
Z
Zheng Yan 已提交
3286 3287
			u32 size;
			struct btrfs_key new_key;
3288 3289 3290
			u64 disko = 0, diskl = 0;
			u64 datao = 0, datal = 0;
			u8 comp;
3291
			u64 drop_start;
Z
Zheng Yan 已提交
3292

3293 3294 3295 3296
			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);
3297 3298
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
C
Chris Mason 已提交
3299 3300 3301 3302
				disko = btrfs_file_extent_disk_bytenr(leaf,
								      extent);
				diskl = btrfs_file_extent_disk_num_bytes(leaf,
								 extent);
3303
				datao = btrfs_file_extent_offset(leaf, extent);
C
Chris Mason 已提交
3304 3305
				datal = btrfs_file_extent_num_bytes(leaf,
								    extent);
3306 3307 3308 3309 3310
			} 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
3311

3312 3313 3314 3315 3316 3317
			/*
			 * 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) {
3318 3319
				path->slots[0]++;
				goto process_slot;
3320 3321
			} else if (key.offset >= off + len) {
				break;
3322 3323 3324 3325 3326 3327 3328 3329 3330
			}

			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;
3331

Z
Zheng Yan 已提交
3332
			memcpy(&new_key, &key, sizeof(new_key));
L
Li Zefan 已提交
3333
			new_key.objectid = btrfs_ino(inode);
3334 3335 3336 3337
			if (off <= key.offset)
				new_key.offset = key.offset + destoff - off;
			else
				new_key.offset = destoff;
Z
Zheng Yan 已提交
3338

3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350
			/*
			 * 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;

3351 3352 3353 3354 3355 3356
			/*
			 * 1 - adjusting old extent (we may have to split it)
			 * 1 - add new extent
			 * 1 - inode update
			 */
			trans = btrfs_start_transaction(root, 3);
3357 3358 3359 3360 3361
			if (IS_ERR(trans)) {
				ret = PTR_ERR(trans);
				goto out;
			}

3362 3363
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
3364 3365 3366 3367 3368
				/*
				 *    a  | --- range to clone ---|  b
				 * | ------------- extent ------------- |
				 */

3369
				/* subtract range b */
3370 3371 3372
				if (key.offset + datal > off + len)
					datal = off + len - key.offset;

3373
				/* subtract range a */
3374 3375 3376 3377 3378
				if (off > key.offset) {
					datao += off - key.offset;
					datal -= off - key.offset;
				}

J
Josef Bacik 已提交
3379
				ret = btrfs_drop_extents(trans, root, inode,
3380
							 drop_start,
3381
							 new_key.offset + datal,
3382
							 1);
3383
				if (ret) {
3384
					if (ret != -EOPNOTSUPP)
3385 3386
						btrfs_abort_transaction(trans,
								root, ret);
3387 3388 3389
					btrfs_end_transaction(trans, root);
					goto out;
				}
3390

3391 3392
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
3393 3394 3395 3396 3397 3398
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
3399 3400 3401 3402

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
Z
Zheng Yan 已提交
3403 3404
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
Y
Yan Zheng 已提交
3405

3406
				extent = btrfs_item_ptr(leaf, slot,
C
Christoph Hellwig 已提交
3407
						struct btrfs_file_extent_item);
3408 3409 3410 3411 3412 3413 3414 3415 3416

				/* 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
3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438

				/*
				 * 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;
					}
				}

3439 3440
				if (disko) {
					inode_add_bytes(inode, datal);
Y
Yan Zheng 已提交
3441
					ret = btrfs_inc_extent_ref(trans, root,
3442 3443
							disko, diskl, 0,
							root->root_key.objectid,
L
Li Zefan 已提交
3444
							btrfs_ino(inode),
A
Arne Jansen 已提交
3445
							new_key.offset - datao,
J
Josef Bacik 已提交
3446
							no_quota);
3447 3448 3449 3450 3451 3452 3453 3454 3455
					if (ret) {
						btrfs_abort_transaction(trans,
									root,
									ret);
						btrfs_end_transaction(trans,
								      root);
						goto out;

					}
C
Christoph Hellwig 已提交
3456
				}
3457 3458 3459
			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
				u64 skip = 0;
				u64 trim = 0;
3460 3461
				u64 aligned_end = 0;

3462 3463 3464 3465
				if (off > key.offset) {
					skip = off - key.offset;
					new_key.offset += skip;
				}
C
Chris Mason 已提交
3466

L
Liu Bo 已提交
3467 3468
				if (key.offset + datal > off + len)
					trim = key.offset + datal - (off + len);
C
Chris Mason 已提交
3469

3470 3471
				if (comp && (skip || trim)) {
					ret = -EINVAL;
3472
					btrfs_end_transaction(trans, root);
3473 3474 3475 3476
					goto out;
				}
				size -= skip + trim;
				datal -= skip + trim;
3477

3478 3479
				aligned_end = ALIGN(new_key.offset + datal,
						    root->sectorsize);
J
Josef Bacik 已提交
3480
				ret = btrfs_drop_extents(trans, root, inode,
3481
							 drop_start,
3482
							 aligned_end,
3483
							 1);
3484
				if (ret) {
3485
					if (ret != -EOPNOTSUPP)
3486 3487
						btrfs_abort_transaction(trans,
							root, ret);
3488 3489 3490
					btrfs_end_transaction(trans, root);
					goto out;
				}
3491

3492 3493
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
3494 3495 3496 3497 3498 3499
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
3500 3501

				if (skip) {
C
Chris Mason 已提交
3502 3503
					u32 start =
					  btrfs_file_extent_calc_inline_size(0);
3504 3505 3506 3507 3508 3509 3510 3511 3512 3513
					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);
3514 3515
				extent = btrfs_item_ptr(leaf, slot,
						struct btrfs_file_extent_item);
C
Christoph Hellwig 已提交
3516
			}
3517

3518 3519 3520 3521 3522 3523 3524 3525 3526
			/* If we have an implicit hole (NO_HOLES feature). */
			if (drop_start < new_key.offset)
				clone_update_extent_map(inode, trans,
						path, NULL, drop_start,
						new_key.offset - drop_start);

			clone_update_extent_map(inode, trans, path,
						extent, 0, 0);

3527
			btrfs_mark_buffer_dirty(leaf);
3528
			btrfs_release_path(path);
3529

3530 3531 3532 3533 3534
			last_dest_end = new_key.offset + datal;
			ret = clone_finish_inode_update(trans, inode,
							last_dest_end,
							destoff, olen);
			if (ret)
3535
				goto out;
3536 3537
			if (new_key.offset + datal >= destoff + len)
				break;
3538
		}
3539
		btrfs_release_path(path);
C
Christoph Hellwig 已提交
3540 3541 3542
		key.offset++;
	}
	ret = 0;
3543

3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569
	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;
		}
		ret = clone_finish_inode_update(trans, inode, destoff + len,
						destoff, olen);
3570 3571 3572 3573
		if (ret)
			goto out;
		clone_update_extent_map(inode, trans, path, NULL, last_dest_end,
					destoff + len - last_dest_end);
3574 3575
	}

C
Christoph Hellwig 已提交
3576
out:
3577 3578 3579 3580 3581 3582 3583 3584
	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
3585
	struct inode *inode = file_inode(file);
3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599
	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.
3600 3601 3602
	 *
	 * - split destination inode's inline extents.  The inline extents can
	 *   be either compressed or non-compressed.
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 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687
	 */

	/* 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;
	}

3688 3689 3690 3691 3692 3693 3694 3695 3696 3697
	/*
	 * 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;
3698

3699 3700 3701 3702 3703
		lock_extent_range(src, lock_start, lock_len);
	} else {
		lock_extent_range(src, off, len);
		lock_extent_range(inode, destoff, len);
	}
3704 3705 3706

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

3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722
	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
3723
out_unlock:
3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734
	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
3735
out_fput:
3736
	fdput(src_file);
3737
out_drop_write:
A
Al Viro 已提交
3738
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
3739 3740 3741
	return ret;
}

3742
static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3743 3744 3745
{
	struct btrfs_ioctl_clone_range_args args;

3746
	if (copy_from_user(&args, argp, sizeof(args)))
3747 3748 3749 3750 3751
		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
3752 3753 3754 3755 3756 3757
/*
 * 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.
 */
3758
static long btrfs_ioctl_trans_start(struct file *file)
C
Christoph Hellwig 已提交
3759
{
A
Al Viro 已提交
3760
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
3761 3762
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
3763
	int ret;
C
Christoph Hellwig 已提交
3764

3765
	ret = -EPERM;
3766
	if (!capable(CAP_SYS_ADMIN))
3767
		goto out;
3768

3769 3770
	ret = -EINPROGRESS;
	if (file->private_data)
C
Christoph Hellwig 已提交
3771
		goto out;
3772

L
Li Zefan 已提交
3773 3774 3775 3776
	ret = -EROFS;
	if (btrfs_root_readonly(root))
		goto out;

3777
	ret = mnt_want_write_file(file);
Y
Yan Zheng 已提交
3778 3779 3780
	if (ret)
		goto out;

J
Josef Bacik 已提交
3781
	atomic_inc(&root->fs_info->open_ioctl_trans);
3782

3783
	ret = -ENOMEM;
3784
	trans = btrfs_start_ioctl_transaction(root);
3785
	if (IS_ERR(trans))
3786 3787 3788 3789 3790 3791
		goto out_drop;

	file->private_data = trans;
	return 0;

out_drop:
J
Josef Bacik 已提交
3792
	atomic_dec(&root->fs_info->open_ioctl_trans);
A
Al Viro 已提交
3793
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
3794 3795 3796 3797
out:
	return ret;
}

3798 3799
static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
{
A
Al Viro 已提交
3800
	struct inode *inode = file_inode(file);
3801 3802 3803 3804 3805 3806 3807 3808 3809
	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;
3810
	int ret;
3811 3812 3813 3814

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

3815 3816 3817 3818 3819 3820 3821 3822
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	if (copy_from_user(&objectid, argp, sizeof(objectid))) {
		ret = -EFAULT;
		goto out;
	}
3823 3824

	if (!objectid)
3825
		objectid = BTRFS_FS_TREE_OBJECTID;
3826 3827 3828 3829 3830 3831

	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);
3832 3833 3834 3835
	if (IS_ERR(new_root)) {
		ret = PTR_ERR(new_root);
		goto out;
	}
3836 3837

	path = btrfs_alloc_path();
3838 3839 3840 3841
	if (!path) {
		ret = -ENOMEM;
		goto out;
	}
3842 3843 3844
	path->leave_spinning = 1;

	trans = btrfs_start_transaction(root, 1);
3845
	if (IS_ERR(trans)) {
3846
		btrfs_free_path(path);
3847 3848
		ret = PTR_ERR(trans);
		goto out;
3849 3850
	}

3851
	dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3852 3853
	di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
				   dir_id, "default", 7, 1);
3854
	if (IS_ERR_OR_NULL(di)) {
3855 3856
		btrfs_free_path(path);
		btrfs_end_transaction(trans, root);
3857 3858
		btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
			   "item, this isn't going to work");
3859 3860
		ret = -ENOENT;
		goto out;
3861 3862 3863 3864 3865 3866 3867
	}

	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);

3868
	btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3869
	btrfs_end_transaction(trans, root);
3870 3871 3872
out:
	mnt_drop_write_file(file);
	return ret;
3873 3874
}

3875 3876
void btrfs_get_block_group_info(struct list_head *groups_list,
				struct btrfs_ioctl_space_info *space)
3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890
{
	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);
	}
}

3891
static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
J
Josef Bacik 已提交
3892 3893 3894 3895
{
	struct btrfs_ioctl_space_args space_args;
	struct btrfs_ioctl_space_info space;
	struct btrfs_ioctl_space_info *dest;
3896
	struct btrfs_ioctl_space_info *dest_orig;
3897
	struct btrfs_ioctl_space_info __user *user_dest;
J
Josef Bacik 已提交
3898
	struct btrfs_space_info *info;
3899 3900 3901 3902 3903
	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;
3904
	int alloc_size;
J
Josef Bacik 已提交
3905
	int ret = 0;
3906
	u64 slot_count = 0;
3907
	int i, c;
J
Josef Bacik 已提交
3908 3909 3910 3911 3912 3913

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

3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937
	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);
	}
3938

3939 3940 3941 3942 3943
	/*
	 * Global block reserve, exported as a space_info
	 */
	slot_count++;

3944 3945 3946 3947 3948
	/* space_slots == 0 means they are asking for a count */
	if (space_args.space_slots == 0) {
		space_args.total_spaces = slot_count;
		goto out;
	}
3949

3950
	slot_count = min_t(u64, space_args.space_slots, slot_count);
3951

3952
	alloc_size = sizeof(*dest) * slot_count;
3953

3954 3955 3956 3957 3958 3959
	/* 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
3960
	space_args.total_spaces = 0;
3961 3962 3963 3964
	dest = kmalloc(alloc_size, GFP_NOFS);
	if (!dest)
		return -ENOMEM;
	dest_orig = dest;
J
Josef Bacik 已提交
3965

3966
	/* now we have a buffer to copy into */
3967 3968 3969
	for (i = 0; i < num_types; i++) {
		struct btrfs_space_info *tmp;

3970 3971 3972
		if (!slot_count)
			break;

3973 3974 3975 3976 3977 3978 3979 3980 3981 3982
		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();
3983

3984 3985 3986 3987 3988
		if (!info)
			continue;
		down_read(&info->groups_sem);
		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
			if (!list_empty(&info->block_groups[c])) {
3989 3990
				btrfs_get_block_group_info(
					&info->block_groups[c], &space);
3991 3992 3993
				memcpy(dest, &space, sizeof(space));
				dest++;
				space_args.total_spaces++;
3994
				slot_count--;
3995
			}
3996 3997
			if (!slot_count)
				break;
3998 3999
		}
		up_read(&info->groups_sem);
J
Josef Bacik 已提交
4000 4001
	}

4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016
	/*
	 * 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
4017
	user_dest = (struct btrfs_ioctl_space_info __user *)
4018 4019 4020 4021 4022 4023 4024 4025
		(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
4026 4027 4028 4029 4030
		ret = -EFAULT;

	return ret;
}

C
Christoph Hellwig 已提交
4031 4032 4033 4034 4035 4036 4037 4038
/*
 * 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
4039
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
4040 4041 4042 4043
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;

	trans = file->private_data;
4044 4045
	if (!trans)
		return -EINVAL;
C
Christoph Hellwig 已提交
4046
	file->private_data = NULL;
4047

4048 4049
	btrfs_end_transaction(trans, root);

J
Josef Bacik 已提交
4050
	atomic_dec(&root->fs_info->open_ioctl_trans);
4051

A
Al Viro 已提交
4052
	mnt_drop_write_file(file);
4053
	return 0;
C
Christoph Hellwig 已提交
4054 4055
}

4056 4057
static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
					    void __user *argp)
4058 4059 4060
{
	struct btrfs_trans_handle *trans;
	u64 transid;
T
Tsutomu Itoh 已提交
4061
	int ret;
4062

M
Miao Xie 已提交
4063
	trans = btrfs_attach_transaction_barrier(root);
4064 4065 4066 4067 4068 4069 4070 4071
	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;
	}
4072
	transid = trans->transid;
T
Tsutomu Itoh 已提交
4073
	ret = btrfs_commit_transaction_async(trans, root, 0);
4074 4075
	if (ret) {
		btrfs_end_transaction(trans, root);
T
Tsutomu Itoh 已提交
4076
		return ret;
4077
	}
4078
out:
4079 4080 4081 4082 4083 4084
	if (argp)
		if (copy_to_user(argp, &transid, sizeof(transid)))
			return -EFAULT;
	return 0;
}

4085 4086
static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
					   void __user *argp)
4087 4088 4089 4090 4091 4092 4093 4094 4095 4096 4097 4098
{
	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
4099
static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
J
Jan Schmidt 已提交
4100
{
A
Al Viro 已提交
4101
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4102
	struct btrfs_ioctl_scrub_args *sa;
M
Miao Xie 已提交
4103
	int ret;
J
Jan Schmidt 已提交
4104 4105 4106 4107 4108 4109 4110 4111

	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
4112 4113 4114 4115 4116 4117
	if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
		ret = mnt_want_write_file(file);
		if (ret)
			goto out;
	}

4118
	ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4119 4120
			      &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
			      0);
J
Jan Schmidt 已提交
4121 4122 4123 4124

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

M
Miao Xie 已提交
4125 4126 4127
	if (!(sa->flags & BTRFS_SCRUB_READONLY))
		mnt_drop_write_file(file);
out:
J
Jan Schmidt 已提交
4128 4129 4130 4131 4132 4133 4134 4135 4136
	kfree(sa);
	return ret;
}

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

4137
	return btrfs_scrub_cancel(root->fs_info);
J
Jan Schmidt 已提交
4138 4139 4140 4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153 4154 4155 4156 4157 4158 4159 4160 4161
}

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;
}

4162
static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4163
				      void __user *arg)
4164 4165 4166 4167 4168 4169 4170 4171
{
	struct btrfs_ioctl_get_dev_stats *sa;
	int ret;

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

4172 4173 4174 4175 4176 4177
	if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
		kfree(sa);
		return -EPERM;
	}

	ret = btrfs_get_dev_stats(root, sa);
4178 4179 4180 4181 4182 4183 4184 4185

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

	kfree(sa);
	return ret;
}

4186 4187 4188 4189 4190 4191 4192 4193 4194 4195 4196 4197 4198 4199
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:
4200 4201 4202 4203
		if (root->fs_info->sb->s_flags & MS_RDONLY) {
			ret = -EROFS;
			goto out;
		}
4204 4205 4206
		if (atomic_xchg(
			&root->fs_info->mutually_exclusive_operation_running,
			1)) {
4207
			ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4208 4209 4210 4211 4212 4213 4214 4215 4216 4217 4218 4219 4220 4221 4222 4223 4224 4225 4226 4227 4228
		} 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;
4229
out:
4230 4231 4232 4233
	kfree(p);
	return ret;
}

4234 4235 4236 4237
static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
{
	int ret = 0;
	int i;
4238
	u64 rel_ptr;
4239
	int size;
4240
	struct btrfs_ioctl_ino_path_args *ipa = NULL;
4241 4242 4243
	struct inode_fs_paths *ipath = NULL;
	struct btrfs_path *path;

4244
	if (!capable(CAP_DAC_READ_SEARCH))
4245 4246 4247 4248 4249 4250 4251 4252 4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272
		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) {
4273 4274
		rel_ptr = ipath->fspath->val[i] -
			  (u64)(unsigned long)ipath->fspath->val;
4275
		ipath->fspath->val[i] = rel_ptr;
4276 4277
	}

4278 4279
	ret = copy_to_user((void *)(unsigned long)ipa->fspath,
			   (void *)(unsigned long)ipath->fspath, size);
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 4324 4325 4326 4327 4328 4329 4330 4331 4332 4333 4334 4335 4336 4337
	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;
	}

4338
	size = min_t(u32, loi->size, 64 * 1024);
4339 4340 4341 4342 4343 4344 4345
	inodes = init_data_container(size);
	if (IS_ERR(inodes)) {
		ret = PTR_ERR(inodes);
		inodes = NULL;
		goto out;
	}

L
Liu Bo 已提交
4346 4347 4348
	ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
					  build_ino_list, inodes);
	if (ret == -EINVAL)
4349 4350 4351 4352
		ret = -ENOENT;
	if (ret < 0)
		goto out;

4353 4354
	ret = copy_to_user((void *)(unsigned long)loi->inodes,
			   (void *)(unsigned long)inodes, size);
4355 4356 4357 4358 4359
	if (ret)
		ret = -EFAULT;

out:
	btrfs_free_path(path);
4360
	vfree(inodes);
4361 4362 4363 4364 4365
	kfree(loi);

	return ret;
}

4366
void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4367 4368 4369 4370 4371 4372
			       struct btrfs_ioctl_balance_args *bargs)
{
	struct btrfs_balance_control *bctl = fs_info->balance_ctl;

	bargs->flags = bctl->flags;

4373 4374 4375 4376
	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;
4377 4378
	if (atomic_read(&fs_info->balance_cancel_req))
		bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4379

4380 4381 4382
	memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
	memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
	memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4383 4384 4385 4386 4387 4388 4389 4390

	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));
	}
4391 4392
}

4393
static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4394
{
A
Al Viro 已提交
4395
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4396 4397 4398
	struct btrfs_fs_info *fs_info = root->fs_info;
	struct btrfs_ioctl_balance_args *bargs;
	struct btrfs_balance_control *bctl;
4399
	bool need_unlock; /* for mut. excl. ops lock */
4400 4401 4402 4403 4404
	int ret;

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

4405
	ret = mnt_want_write_file(file);
4406 4407 4408
	if (ret)
		return ret;

4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422
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)
	 */
4423
	mutex_lock(&fs_info->balance_mutex);
4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450
	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);
4451
		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4452 4453 4454 4455 4456
		goto out;
	}

locked:
	BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4457 4458 4459 4460 4461

	if (arg) {
		bargs = memdup_user(arg, sizeof(*bargs));
		if (IS_ERR(bargs)) {
			ret = PTR_ERR(bargs);
4462
			goto out_unlock;
4463
		}
4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477

		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;
		}
4478 4479 4480 4481
	} else {
		bargs = NULL;
	}

4482
	if (fs_info->balance_ctl) {
4483 4484 4485 4486
		ret = -EINPROGRESS;
		goto out_bargs;
	}

4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498 4499
	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;
4500 4501 4502
	} else {
		/* balance everything - no filters */
		bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4503 4504
	}

4505
do_balance:
4506
	/*
4507 4508 4509 4510 4511
	 * 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.
4512
	 */
4513 4514 4515 4516
	need_unlock = false;

	ret = btrfs_balance(bctl, bargs);

4517 4518 4519 4520 4521 4522 4523
	if (arg) {
		if (copy_to_user(arg, bargs, sizeof(*bargs)))
			ret = -EFAULT;
	}

out_bargs:
	kfree(bargs);
4524
out_unlock:
4525 4526
	mutex_unlock(&fs_info->balance_mutex);
	mutex_unlock(&fs_info->volume_mutex);
4527 4528 4529
	if (need_unlock)
		atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
out:
4530
	mnt_drop_write_file(file);
4531 4532 4533
	return ret;
}

4534 4535 4536 4537 4538 4539 4540 4541
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);
4542 4543
	case BTRFS_BALANCE_CTL_CANCEL:
		return btrfs_cancel_balance(root->fs_info);
4544 4545 4546 4547 4548
	}

	return -EINVAL;
}

4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581
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;
}

4582
static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4583
{
A
Al Viro 已提交
4584
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4585 4586 4587 4588 4589 4590 4591 4592
	struct btrfs_ioctl_quota_ctl_args *sa;
	struct btrfs_trans_handle *trans = NULL;
	int ret;
	int err;

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

4593 4594 4595
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4596 4597

	sa = memdup_user(arg, sizeof(*sa));
4598 4599 4600 4601
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4602

4603
	down_write(&root->fs_info->subvol_sem);
J
Jan Schmidt 已提交
4604 4605 4606 4607
	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
4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621
	}

	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
4622 4623 4624
	err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
	if (err && !ret)
		ret = err;
A
Arne Jansen 已提交
4625 4626
out:
	kfree(sa);
4627
	up_write(&root->fs_info->subvol_sem);
4628 4629
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4630 4631 4632
	return ret;
}

4633
static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4634
{
A
Al Viro 已提交
4635
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4636 4637 4638 4639 4640 4641 4642 4643
	struct btrfs_ioctl_qgroup_assign_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;

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

4644 4645 4646
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4647 4648

	sa = memdup_user(arg, sizeof(*sa));
4649 4650 4651 4652
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4653 4654 4655 4656 4657 4658 4659 4660 4661 4662 4663 4664 4665 4666 4667 4668 4669 4670 4671 4672 4673 4674

	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);
4675 4676
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4677 4678 4679
	return ret;
}

4680
static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4681
{
A
Al Viro 已提交
4682
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4683 4684 4685 4686 4687 4688 4689 4690
	struct btrfs_ioctl_qgroup_create_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;

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

4691 4692 4693
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4694 4695

	sa = memdup_user(arg, sizeof(*sa));
4696 4697 4698 4699
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4700

M
Miao Xie 已提交
4701 4702 4703 4704 4705
	if (!sa->qgroupid) {
		ret = -EINVAL;
		goto out;
	}

A
Arne Jansen 已提交
4706 4707 4708 4709 4710 4711 4712 4713 4714 4715 4716 4717 4718 4719 4720 4721 4722 4723 4724 4725
	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);
4726 4727
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4728 4729 4730
	return ret;
}

4731
static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4732
{
A
Al Viro 已提交
4733
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4734 4735 4736 4737 4738 4739 4740 4741 4742
	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;

4743 4744 4745
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4746 4747

	sa = memdup_user(arg, sizeof(*sa));
4748 4749 4750 4751
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773

	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);
4774 4775
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4776 4777 4778
	return ret;
}

J
Jan Schmidt 已提交
4779 4780
static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4781
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813
	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
4814
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4815 4816 4817 4818 4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836
	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;
}

4837 4838
static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4839
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4840 4841 4842 4843 4844 4845 4846

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

	return btrfs_qgroup_wait_for_completion(root->fs_info);
}

4847 4848
static long _btrfs_ioctl_set_received_subvol(struct file *file,
					    struct btrfs_ioctl_received_subvol_args *sa)
4849
{
A
Al Viro 已提交
4850
	struct inode *inode = file_inode(file);
4851 4852 4853 4854 4855
	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;
4856
	int received_uuid_changed;
4857

4858 4859 4860
	if (!inode_owner_or_capable(inode))
		return -EPERM;

4861 4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876
	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;
	}

4877 4878 4879 4880 4881
	/*
	 * 1 - root item
	 * 2 - uuid items (received uuid + subvol uuid)
	 */
	trans = btrfs_start_transaction(root, 3);
4882 4883 4884 4885 4886 4887 4888 4889 4890 4891
	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;

4892 4893 4894 4895 4896 4897 4898 4899
	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);
4900 4901 4902
	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);
4903 4904 4905 4906
	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);
4907 4908 4909 4910 4911 4912

	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;
4913 4914 4915 4916 4917 4918 4919 4920
	}
	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);
4921
			goto out;
4922 4923 4924 4925 4926 4927
		}
	}
	ret = btrfs_commit_transaction(trans, root);
	if (ret < 0) {
		btrfs_abort_transaction(trans, root, ret);
		goto out;
4928 4929
	}

4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951
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);
4952 4953
	if (!args64) {
		ret = -ENOMEM;
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 4994 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007
		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;

5008 5009 5010 5011 5012 5013 5014 5015 5016
	ret = copy_to_user(arg, sa, sizeof(*sa));
	if (ret)
		ret = -EFAULT;

out:
	kfree(sa);
	return ret;
}

5017 5018
static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
{
A
Al Viro 已提交
5019
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5020
	size_t len;
5021
	int ret;
5022 5023 5024 5025 5026 5027 5028
	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);
5029 5030

	if (len == BTRFS_LABEL_SIZE) {
5031 5032
		btrfs_warn(root->fs_info,
			"label is too long, return the first %zu bytes", --len);
5033 5034 5035 5036 5037 5038 5039
	}

	ret = copy_to_user(arg, label, len);

	return ret ? -EFAULT : 0;
}

5040 5041
static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
{
A
Al Viro 已提交
5042
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054
	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) {
5055
		btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069
		       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;
	}

5070
	spin_lock(&root->fs_info->super_lock);
5071
	strcpy(super_block->label, label);
5072
	spin_unlock(&root->fs_info->super_lock);
5073
	ret = btrfs_commit_transaction(trans, root);
5074 5075 5076 5077 5078 5079

out_unlock:
	mnt_drop_write_file(file);
	return ret;
}

5080 5081 5082 5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115
#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;
}

5116 5117
static int check_feature_bits(struct btrfs_root *root,
			      enum btrfs_feature_set set,
5118 5119 5120
			      u64 change_mask, u64 flags, u64 supported_flags,
			      u64 safe_set, u64 safe_clear)
{
5121 5122
	const char *type = btrfs_feature_set_names[set];
	char *names;
5123 5124 5125 5126 5127 5128
	u64 disallowed, unsupported;
	u64 set_mask = flags & change_mask;
	u64 clear_mask = ~flags & change_mask;

	unsupported = set_mask & ~supported_flags;
	if (unsupported) {
5129 5130 5131 5132 5133 5134 5135 5136
		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,
5137 5138 5139 5140 5141 5142 5143
			   "this kernel does not support %s bits 0x%llx",
			   type, unsupported);
		return -EOPNOTSUPP;
	}

	disallowed = set_mask & ~safe_set;
	if (disallowed) {
5144 5145 5146 5147 5148 5149 5150 5151
		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,
5152 5153 5154 5155 5156 5157 5158
			   "can't set %s bits 0x%llx while mounted",
			   type, disallowed);
		return -EPERM;
	}

	disallowed = clear_mask & ~safe_clear;
	if (disallowed) {
5159 5160 5161 5162 5163 5164 5165 5166
		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,
5167 5168 5169 5170 5171 5172 5173 5174 5175
			   "can't clear %s bits 0x%llx while mounted",
			   type, disallowed);
		return -EPERM;
	}

	return 0;
}

#define check_feature(root, change_mask, flags, mask_base)	\
5176
check_feature_bits(root, FEAT_##mask_base, change_mask, flags,	\
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 5202 5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215
		   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;

5216
	trans = btrfs_start_transaction(root, 0);
5217 5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236
	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);

5237
	return btrfs_commit_transaction(trans, root);
5238 5239
}

C
Christoph Hellwig 已提交
5240 5241 5242
long btrfs_ioctl(struct file *file, unsigned int
		cmd, unsigned long arg)
{
A
Al Viro 已提交
5243
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5244
	void __user *argp = (void __user *)arg;
C
Christoph Hellwig 已提交
5245 5246

	switch (cmd) {
5247 5248 5249 5250 5251 5252
	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);
5253 5254
	case FITRIM:
		return btrfs_ioctl_fitrim(file, argp);
C
Christoph Hellwig 已提交
5255
	case BTRFS_IOC_SNAP_CREATE:
5256
		return btrfs_ioctl_snap_create(file, argp, 0);
5257
	case BTRFS_IOC_SNAP_CREATE_V2:
5258
		return btrfs_ioctl_snap_create_v2(file, argp, 0);
5259
	case BTRFS_IOC_SUBVOL_CREATE:
5260
		return btrfs_ioctl_snap_create(file, argp, 1);
A
Arne Jansen 已提交
5261 5262
	case BTRFS_IOC_SUBVOL_CREATE_V2:
		return btrfs_ioctl_snap_create_v2(file, argp, 1);
5263 5264
	case BTRFS_IOC_SNAP_DESTROY:
		return btrfs_ioctl_snap_destroy(file, argp);
5265 5266 5267 5268
	case BTRFS_IOC_SUBVOL_GETFLAGS:
		return btrfs_ioctl_subvol_getflags(file, argp);
	case BTRFS_IOC_SUBVOL_SETFLAGS:
		return btrfs_ioctl_subvol_setflags(file, argp);
5269 5270
	case BTRFS_IOC_DEFAULT_SUBVOL:
		return btrfs_ioctl_default_subvol(file, argp);
C
Christoph Hellwig 已提交
5271
	case BTRFS_IOC_DEFRAG:
C
Chris Mason 已提交
5272 5273 5274
		return btrfs_ioctl_defrag(file, NULL);
	case BTRFS_IOC_DEFRAG_RANGE:
		return btrfs_ioctl_defrag(file, argp);
C
Christoph Hellwig 已提交
5275
	case BTRFS_IOC_RESIZE:
5276
		return btrfs_ioctl_resize(file, argp);
C
Christoph Hellwig 已提交
5277
	case BTRFS_IOC_ADD_DEV:
5278
		return btrfs_ioctl_add_dev(root, argp);
C
Christoph Hellwig 已提交
5279
	case BTRFS_IOC_RM_DEV:
5280
		return btrfs_ioctl_rm_dev(file, argp);
J
Jan Schmidt 已提交
5281 5282 5283 5284
	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
5285
	case BTRFS_IOC_BALANCE:
5286
		return btrfs_ioctl_balance(file, NULL);
C
Christoph Hellwig 已提交
5287
	case BTRFS_IOC_CLONE:
5288 5289
		return btrfs_ioctl_clone(file, arg, 0, 0, 0);
	case BTRFS_IOC_CLONE_RANGE:
5290
		return btrfs_ioctl_clone_range(file, argp);
C
Christoph Hellwig 已提交
5291 5292 5293 5294
	case BTRFS_IOC_TRANS_START:
		return btrfs_ioctl_trans_start(file);
	case BTRFS_IOC_TRANS_END:
		return btrfs_ioctl_trans_end(file);
5295 5296
	case BTRFS_IOC_TREE_SEARCH:
		return btrfs_ioctl_tree_search(file, argp);
G
Gerhard Heift 已提交
5297 5298
	case BTRFS_IOC_TREE_SEARCH_V2:
		return btrfs_ioctl_tree_search_v2(file, argp);
5299 5300
	case BTRFS_IOC_INO_LOOKUP:
		return btrfs_ioctl_ino_lookup(file, argp);
5301 5302 5303 5304
	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
5305 5306
	case BTRFS_IOC_SPACE_INFO:
		return btrfs_ioctl_space_info(root, argp);
5307 5308 5309
	case BTRFS_IOC_SYNC: {
		int ret;

5310
		ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5311 5312 5313 5314 5315
		if (ret)
			return ret;
		ret = btrfs_sync_fs(file->f_dentry->d_sb, 1);
		return ret;
	}
5316
	case BTRFS_IOC_START_SYNC:
5317
		return btrfs_ioctl_start_sync(root, argp);
5318
	case BTRFS_IOC_WAIT_SYNC:
5319
		return btrfs_ioctl_wait_sync(root, argp);
J
Jan Schmidt 已提交
5320
	case BTRFS_IOC_SCRUB:
M
Miao Xie 已提交
5321
		return btrfs_ioctl_scrub(file, argp);
J
Jan Schmidt 已提交
5322 5323 5324 5325
	case BTRFS_IOC_SCRUB_CANCEL:
		return btrfs_ioctl_scrub_cancel(root, argp);
	case BTRFS_IOC_SCRUB_PROGRESS:
		return btrfs_ioctl_scrub_progress(root, argp);
5326
	case BTRFS_IOC_BALANCE_V2:
5327
		return btrfs_ioctl_balance(file, argp);
5328 5329
	case BTRFS_IOC_BALANCE_CTL:
		return btrfs_ioctl_balance_ctl(root, arg);
5330 5331
	case BTRFS_IOC_BALANCE_PROGRESS:
		return btrfs_ioctl_balance_progress(root, argp);
5332 5333
	case BTRFS_IOC_SET_RECEIVED_SUBVOL:
		return btrfs_ioctl_set_received_subvol(file, argp);
5334 5335 5336 5337
#ifdef CONFIG_64BIT
	case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
		return btrfs_ioctl_set_received_subvol_32(file, argp);
#endif
5338 5339
	case BTRFS_IOC_SEND:
		return btrfs_ioctl_send(file, argp);
5340
	case BTRFS_IOC_GET_DEV_STATS:
5341
		return btrfs_ioctl_get_dev_stats(root, argp);
A
Arne Jansen 已提交
5342
	case BTRFS_IOC_QUOTA_CTL:
5343
		return btrfs_ioctl_quota_ctl(file, argp);
A
Arne Jansen 已提交
5344
	case BTRFS_IOC_QGROUP_ASSIGN:
5345
		return btrfs_ioctl_qgroup_assign(file, argp);
A
Arne Jansen 已提交
5346
	case BTRFS_IOC_QGROUP_CREATE:
5347
		return btrfs_ioctl_qgroup_create(file, argp);
A
Arne Jansen 已提交
5348
	case BTRFS_IOC_QGROUP_LIMIT:
5349
		return btrfs_ioctl_qgroup_limit(file, argp);
J
Jan Schmidt 已提交
5350 5351 5352 5353
	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);
5354 5355
	case BTRFS_IOC_QUOTA_RESCAN_WAIT:
		return btrfs_ioctl_quota_rescan_wait(file, argp);
5356 5357
	case BTRFS_IOC_DEV_REPLACE:
		return btrfs_ioctl_dev_replace(root, argp);
5358 5359
	case BTRFS_IOC_GET_FSLABEL:
		return btrfs_ioctl_get_fslabel(file, argp);
5360 5361
	case BTRFS_IOC_SET_FSLABEL:
		return btrfs_ioctl_set_fslabel(file, argp);
M
Mark Fasheh 已提交
5362 5363
	case BTRFS_IOC_FILE_EXTENT_SAME:
		return btrfs_ioctl_file_extent_same(file, argp);
5364 5365 5366 5367 5368 5369
	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
5370 5371 5372 5373
	}

	return -ENOTTY;
}