ioctl.c 136.9 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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#include "tree-log.h"
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#include "compression.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,
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		       u64 off, u64 olen, u64 olen_aligned, u64 destoff,
		       int no_time_update);
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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;

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	if (flags & BTRFS_INODE_NOCOMPRESS)
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		iflags |= FS_NOCOMP_FL;
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	else if (flags & BTRFS_INODE_COMPRESS)
		iflags |= FS_COMPR_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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	inode_lock(inode);
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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 {
		/*
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		 * Revert back under same assumptions as above
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		 */
		if (S_ISREG(mode)) {
			if (inode->i_size == 0)
				ip->flags &= ~(BTRFS_INODE_NODATACOW
				             | BTRFS_INODE_NODATASUM);
		} else {
			ip->flags &= ~BTRFS_INODE_NODATACOW;
		}
	}
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	/*
	 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
	 * flag may be changed automatically if compression code won't make
	 * things smaller.
	 */
	if (flags & FS_NOCOMP_FL) {
		ip->flags &= ~BTRFS_INODE_COMPRESS;
		ip->flags |= BTRFS_INODE_NOCOMPRESS;
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		ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
		if (ret && ret != -ENODATA)
			goto out_drop;
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	} else if (flags & FS_COMPR_FL) {
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		const char *comp;

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

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	} else {
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		ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
		if (ret && ret != -ENODATA)
			goto out_drop;
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		ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
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	}
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	trans = btrfs_start_transaction(root, 1);
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	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out_drop;
	}
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	btrfs_update_iflags(inode);
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	inode_inc_iversion(inode);
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	inode->i_ctime = current_fs_time(inode->i_sb);
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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:
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	inode_unlock(inode);
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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);
		}
	}
401
	rcu_read_unlock();
402

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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)
409
		return -EINVAL;
410

411
	range.len = min(range.len, total_bytes - range.start);
412
	range.minlen = max(range.minlen, minlen);
413
	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;
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}

434
static noinline int create_subvol(struct inode *dir,
435
				  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;
442
	struct btrfs_root_item *root_item;
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	struct btrfs_inode_item *inode_item;
	struct extent_buffer *leaf;
445
	struct btrfs_root *root = BTRFS_I(dir)->root;
446
	struct btrfs_root *new_root;
447
	struct btrfs_block_rsv block_rsv;
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	struct timespec cur_time = current_fs_time(dir->i_sb);
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	struct inode *inode;
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	int ret;
	int err;
	u64 objectid;
	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
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	u64 index = 0;
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	u64 qgroup_reserved;
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	uuid_le new_uuid;
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	root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
	if (!root_item)
		return -ENOMEM;

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	ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
463
	if (ret)
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		goto fail_free;
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	/*
	 * Don't create subvolume whose level is not zero. Or qgroup will be
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	 * screwed up since it assumes subvolume qgroup's level to be 0.
469
	 */
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	if (btrfs_qgroup_level(objectid)) {
		ret = -ENOSPC;
		goto fail_free;
	}
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475
	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
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	/*
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	 * The same as the snapshot creation, please see the comment
	 * of create_snapshot().
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	 */
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	ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
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					       8, &qgroup_reserved, false);
482
	if (ret)
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		goto fail_free;
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	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);
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		goto fail_free;
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	}
	trans->block_rsv = &block_rsv;
	trans->bytes_reserved = block_rsv.size;
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	ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
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	if (ret)
		goto fail;

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	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
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	if (IS_ERR(leaf)) {
		ret = PTR_ERR(leaf);
		goto fail;
	}
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505
	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);

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

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	inode_item = &root_item->inode;
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	btrfs_set_stack_inode_generation(inode_item, 1);
	btrfs_set_stack_inode_size(inode_item, 3);
	btrfs_set_stack_inode_nlink(inode_item, 1);
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	btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
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	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
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	btrfs_set_root_flags(root_item, 0);
	btrfs_set_root_limit(root_item, 0);
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	btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
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	btrfs_set_root_bytenr(root_item, leaf->start);
	btrfs_set_root_generation(root_item, trans->transid);
	btrfs_set_root_level(root_item, 0);
	btrfs_set_root_refs(root_item, 1);
	btrfs_set_root_used(root_item, leaf->len);
	btrfs_set_root_last_snapshot(root_item, 0);
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	btrfs_set_root_generation_v2(root_item,
			btrfs_root_generation(root_item));
538
	uuid_le_gen(&new_uuid);
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	memcpy(root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
	btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
	btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
	root_item->ctime = root_item->otime;
	btrfs_set_root_ctransid(root_item, trans->transid);
	btrfs_set_root_otransid(root_item, trans->transid);
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546
	btrfs_tree_unlock(leaf);
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	free_extent_buffer(leaf);
	leaf = NULL;

550
	btrfs_set_root_dirid(root_item, new_dirid);
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	key.objectid = objectid;
553
	key.offset = 0;
554
	key.type = BTRFS_ROOT_ITEM_KEY;
C
Christoph Hellwig 已提交
555
	ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
556
				root_item);
C
Christoph Hellwig 已提交
557 558 559
	if (ret)
		goto fail;

560 561
	key.offset = (u64)-1;
	new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
562 563
	if (IS_ERR(new_root)) {
		ret = PTR_ERR(new_root);
564
		btrfs_abort_transaction(trans, root, ret);
565 566
		goto fail;
	}
567 568 569

	btrfs_record_root_in_trans(trans, new_root);

570
	ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
571 572
	if (ret) {
		/* We potentially lose an unused inode item here */
573
		btrfs_abort_transaction(trans, root, ret);
574 575 576
		goto fail;
	}

577 578 579 580
	mutex_lock(&new_root->objectid_mutex);
	new_root->highest_objectid = new_dirid;
	mutex_unlock(&new_root->objectid_mutex);

C
Christoph Hellwig 已提交
581 582 583
	/*
	 * insert the directory item
	 */
584
	ret = btrfs_set_inode_index(dir, &index);
585 586 587 588
	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
		goto fail;
	}
589 590

	ret = btrfs_insert_dir_item(trans, root,
591
				    name, namelen, dir, &key,
592
				    BTRFS_FT_DIR, index);
593 594
	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
C
Christoph Hellwig 已提交
595
		goto fail;
596
	}
597

598 599 600 601
	btrfs_i_size_write(dir, dir->i_size + namelen * 2);
	ret = btrfs_update_inode(trans, root, dir);
	BUG_ON(ret);

602
	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
603
				 objectid, root->root_key.objectid,
L
Li Zefan 已提交
604
				 btrfs_ino(dir), index, name, namelen);
605
	BUG_ON(ret);
C
Christoph Hellwig 已提交
606

607
	ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
608
				  root_item->uuid, BTRFS_UUID_KEY_SUBVOL,
609 610 611 612
				  objectid);
	if (ret)
		btrfs_abort_transaction(trans, root, ret);

C
Christoph Hellwig 已提交
613
fail:
614
	kfree(root_item);
615 616
	trans->block_rsv = NULL;
	trans->bytes_reserved = 0;
617 618
	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);

S
Sage Weil 已提交
619 620 621
	if (async_transid) {
		*async_transid = trans->transid;
		err = btrfs_commit_transaction_async(trans, root, 1);
622 623
		if (err)
			err = btrfs_commit_transaction(trans, root);
S
Sage Weil 已提交
624 625 626
	} else {
		err = btrfs_commit_transaction(trans, root);
	}
C
Christoph Hellwig 已提交
627 628
	if (err && !ret)
		ret = err;
629

630 631
	if (!ret) {
		inode = btrfs_lookup_dentry(dir, dentry);
632 633
		if (IS_ERR(inode))
			return PTR_ERR(inode);
634 635
		d_instantiate(dentry, inode);
	}
C
Christoph Hellwig 已提交
636
	return ret;
637 638 639 640

fail_free:
	kfree(root_item);
	return ret;
C
Christoph Hellwig 已提交
641 642
}

643
static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659
{
	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);
}

660 661 662 663
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
664
{
665
	struct inode *inode;
C
Christoph Hellwig 已提交
666 667
	struct btrfs_pending_snapshot *pending_snapshot;
	struct btrfs_trans_handle *trans;
668
	int ret;
C
Christoph Hellwig 已提交
669

670
	if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
C
Christoph Hellwig 已提交
671 672
		return -EINVAL;

673 674 675 676
	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
	if (!pending_snapshot)
		return -ENOMEM;

677 678
	pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
			GFP_NOFS);
679 680
	pending_snapshot->path = btrfs_alloc_path();
	if (!pending_snapshot->root_item || !pending_snapshot->path) {
681 682 683 684
		ret = -ENOMEM;
		goto free_pending;
	}

685
	atomic_inc(&root->will_be_snapshoted);
686
	smp_mb__after_atomic();
687
	btrfs_wait_for_no_snapshoting_writes(root);
688

689 690
	ret = btrfs_start_delalloc_inodes(root, 0);
	if (ret)
691
		goto dec_and_free;
692

693
	btrfs_wait_ordered_extents(root, -1, 0, (u64)-1);
694

695 696
	btrfs_init_block_rsv(&pending_snapshot->block_rsv,
			     BTRFS_BLOCK_RSV_TEMP);
697 698 699 700 701 702
	/*
	 * 1 - parent dir inode
	 * 2 - dir entries
	 * 1 - root item
	 * 2 - root ref/backref
	 * 1 - root of snapshot
703
	 * 1 - UUID item
704 705
	 */
	ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
706
					&pending_snapshot->block_rsv, 8,
707 708
					&pending_snapshot->qgroup_reserved,
					false);
709
	if (ret)
710
		goto dec_and_free;
711

712
	pending_snapshot->dentry = dentry;
C
Christoph Hellwig 已提交
713
	pending_snapshot->root = root;
L
Li Zefan 已提交
714
	pending_snapshot->readonly = readonly;
715
	pending_snapshot->dir = dir;
716
	pending_snapshot->inherit = inherit;
717

718
	trans = btrfs_start_transaction(root, 0);
719 720 721 722 723
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto fail;
	}

724
	spin_lock(&root->fs_info->trans_lock);
C
Christoph Hellwig 已提交
725 726
	list_add(&pending_snapshot->list,
		 &trans->transaction->pending_snapshots);
727
	spin_unlock(&root->fs_info->trans_lock);
S
Sage Weil 已提交
728 729 730 731
	if (async_transid) {
		*async_transid = trans->transid;
		ret = btrfs_commit_transaction_async(trans,
				     root->fs_info->extent_root, 1);
732 733
		if (ret)
			ret = btrfs_commit_transaction(trans, root);
S
Sage Weil 已提交
734 735 736 737
	} else {
		ret = btrfs_commit_transaction(trans,
					       root->fs_info->extent_root);
	}
738
	if (ret)
739
		goto fail;
740 741 742 743 744

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

745 746 747 748
	ret = btrfs_orphan_cleanup(pending_snapshot->snap);
	if (ret)
		goto fail;

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

755 756 757
	d_instantiate(dentry, inode);
	ret = 0;
fail:
758 759 760
	btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
					 &pending_snapshot->block_rsv,
					 pending_snapshot->qgroup_reserved);
761
dec_and_free:
762 763
	if (atomic_dec_and_test(&root->will_be_snapshoted))
		wake_up_atomic_t(&root->will_be_snapshoted);
764 765
free_pending:
	kfree(pending_snapshot->root_item);
766
	btrfs_free_path(pending_snapshot->path);
767 768
	kfree(pending_snapshot);

C
Christoph Hellwig 已提交
769 770 771
	return ret;
}

772 773 774 775 776 777 778 779 780 781 782
/*  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
783
 *  6. If the victim is append-only or immutable we can't do anything with
784 785 786 787 788 789 790 791
 *     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().
 */

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

796
	if (d_really_is_negative(victim))
797 798
		return -ENOENT;

799
	BUG_ON(d_inode(victim->d_parent) != dir);
800
	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
801 802 803 804 805 806

	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		return error;
	if (IS_APPEND(dir))
		return -EPERM;
807 808
	if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
	    IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
809 810
		return -EPERM;
	if (isdir) {
811
		if (!d_is_dir(victim))
812 813 814
			return -ENOTDIR;
		if (IS_ROOT(victim))
			return -EBUSY;
815
	} else if (d_is_dir(victim))
816 817 818 819 820 821 822 823
		return -EISDIR;
	if (IS_DEADDIR(dir))
		return -ENOENT;
	if (victim->d_flags & DCACHE_NFSFS_RENAMED)
		return -EBUSY;
	return 0;
}

824 825 826
/* copy of may_create in fs/namei.c() */
static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
{
827
	if (d_really_is_positive(child))
828 829 830 831 832 833 834 835 836 837 838
		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.
 */
839 840
static noinline int btrfs_mksubvol(struct path *parent,
				   char *name, int namelen,
S
Sage Weil 已提交
841
				   struct btrfs_root *snap_src,
A
Arne Jansen 已提交
842
				   u64 *async_transid, bool readonly,
843
				   struct btrfs_qgroup_inherit *inherit)
844
{
845
	struct inode *dir  = d_inode(parent->dentry);
846 847 848
	struct dentry *dentry;
	int error;

849 850 851
	error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
	if (error == -EINTR)
		return error;
852 853 854 855 856 857

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

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

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

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

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

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

C
Chris Mason 已提交
895 896 897 898 899 900 901
/*
 * When we're defragging a range, we don't want to kick it off again
 * if it is really just waiting for delalloc to send it down.
 * If we find a nice big extent or delalloc range for the bytes in the
 * file you want to defrag, we return 0 to let you know to skip this
 * part of the file
 */
902
static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
C
Chris Mason 已提交
903 904 905 906 907 908 909
{
	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);
910
	em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
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
	read_unlock(&em_tree->lock);

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

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

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

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

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

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

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

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

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

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

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

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

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

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

		if (IS_ERR(em))
			return NULL;
	}

	return em;
}
1025

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

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

	next = defrag_lookup_extent(inode, em->start + em->len);
1036 1037 1038
	if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
		ret = false;
	else if ((em->block_start + em->block_len == next->block_start) &&
1039
		 (em->block_len > SZ_128K && next->block_len > SZ_128K))
L
Li Zefan 已提交
1040 1041 1042
		ret = false;

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

1046
static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1047 1048
			       u64 *last_len, u64 *skip, u64 *defrag_end,
			       int compress)
1049
{
L
Li Zefan 已提交
1050
	struct extent_map *em;
1051
	int ret = 1;
L
Li Zefan 已提交
1052
	bool next_mergeable = true;
1053
	bool prev_mergeable = true;
1054 1055

	/*
1056
	 * make sure that once we start defragging an extent, we keep on
1057 1058 1059 1060 1061 1062 1063
	 * defragging it
	 */
	if (start < *defrag_end)
		return 1;

	*skip = 0;

L
Li Zefan 已提交
1064 1065 1066
	em = defrag_lookup_extent(inode, start);
	if (!em)
		return 0;
1067 1068

	/* this will cover holes, and inline extents */
1069
	if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1070
		ret = 0;
1071 1072 1073
		goto out;
	}

1074 1075 1076
	if (!*defrag_end)
		prev_mergeable = false;

L
Li Zefan 已提交
1077
	next_mergeable = defrag_check_next_extent(inode, em);
1078
	/*
L
Li Zefan 已提交
1079 1080
	 * we hit a real extent, if it is big or the next extent is not a
	 * real extent, don't bother defragging it
1081
	 */
1082
	if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1083
	    (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1084
		ret = 0;
1085
out:
1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105
	/*
	 * 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
1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120
/*
 * 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,
1121
				    unsigned long num_pages)
C
Christoph Hellwig 已提交
1122
{
C
Chris Mason 已提交
1123 1124 1125 1126
	unsigned long file_end;
	u64 isize = i_size_read(inode);
	u64 page_start;
	u64 page_end;
1127
	u64 page_cnt;
C
Chris Mason 已提交
1128 1129 1130
	int ret;
	int i;
	int i_done;
1131
	struct btrfs_ordered_extent *ordered;
C
Chris Mason 已提交
1132
	struct extent_state *cached_state = NULL;
1133
	struct extent_io_tree *tree;
1134
	gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
C
Chris Mason 已提交
1135

1136
	file_end = (isize - 1) >> PAGE_SHIFT;
1137 1138 1139 1140
	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
1141 1142

	ret = btrfs_delalloc_reserve_space(inode,
1143 1144
			start_index << PAGE_SHIFT,
			page_cnt << PAGE_SHIFT);
C
Chris Mason 已提交
1145 1146 1147
	if (ret)
		return ret;
	i_done = 0;
1148
	tree = &BTRFS_I(inode)->io_tree;
C
Chris Mason 已提交
1149 1150

	/* step one, lock all the pages */
1151
	for (i = 0; i < page_cnt; i++) {
C
Chris Mason 已提交
1152
		struct page *page;
1153
again:
1154
		page = find_or_create_page(inode->i_mapping,
1155
					   start_index + i, mask);
C
Chris Mason 已提交
1156 1157 1158
		if (!page)
			break;

1159
		page_start = page_offset(page);
1160
		page_end = page_start + PAGE_SIZE - 1;
1161
		while (1) {
1162
			lock_extent_bits(tree, page_start, page_end,
1163
					 &cached_state);
1164 1165
			ordered = btrfs_lookup_ordered_extent(inode,
							      page_start);
1166 1167
			unlock_extent_cached(tree, page_start, page_end,
					     &cached_state, GFP_NOFS);
1168 1169 1170 1171 1172 1173 1174
			if (!ordered)
				break;

			unlock_page(page);
			btrfs_start_ordered_extent(inode, ordered, 1);
			btrfs_put_ordered_extent(ordered);
			lock_page(page);
1175 1176 1177 1178 1179 1180
			/*
			 * we unlocked the page above, so we need check if
			 * it was released or not.
			 */
			if (page->mapping != inode->i_mapping) {
				unlock_page(page);
1181
				put_page(page);
1182 1183
				goto again;
			}
1184 1185
		}

C
Chris Mason 已提交
1186 1187 1188 1189 1190
		if (!PageUptodate(page)) {
			btrfs_readpage(NULL, page);
			lock_page(page);
			if (!PageUptodate(page)) {
				unlock_page(page);
1191
				put_page(page);
C
Chris Mason 已提交
1192 1193 1194 1195
				ret = -EIO;
				break;
			}
		}
1196 1197 1198

		if (page->mapping != inode->i_mapping) {
			unlock_page(page);
1199
			put_page(page);
1200 1201 1202
			goto again;
		}

C
Chris Mason 已提交
1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219
		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]);
1220
	page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
C
Chris Mason 已提交
1221 1222

	lock_extent_bits(&BTRFS_I(inode)->io_tree,
1223
			 page_start, page_end - 1, &cached_state);
C
Chris Mason 已提交
1224 1225
	clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
			  page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1226 1227
			  EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
			  &cached_state, GFP_NOFS);
C
Chris Mason 已提交
1228

1229
	if (i_done != page_cnt) {
1230 1231 1232
		spin_lock(&BTRFS_I(inode)->lock);
		BTRFS_I(inode)->outstanding_extents++;
		spin_unlock(&BTRFS_I(inode)->lock);
C
Chris Mason 已提交
1233
		btrfs_delalloc_release_space(inode,
1234 1235
				start_index << PAGE_SHIFT,
				(page_cnt - i_done) << PAGE_SHIFT);
C
Chris Mason 已提交
1236 1237 1238
	}


1239
	set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1240
			  &cached_state);
C
Chris Mason 已提交
1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251

	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]);
1252
		put_page(pages[i]);
C
Chris Mason 已提交
1253 1254 1255 1256 1257
	}
	return i_done;
out:
	for (i = 0; i < i_done; i++) {
		unlock_page(pages[i]);
1258
		put_page(pages[i]);
C
Chris Mason 已提交
1259
	}
1260
	btrfs_delalloc_release_space(inode,
1261 1262
			start_index << PAGE_SHIFT,
			page_cnt << PAGE_SHIFT);
C
Chris Mason 已提交
1263 1264 1265 1266 1267 1268 1269 1270 1271 1272
	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
1273
	unsigned long last_index;
1274
	u64 isize = i_size_read(inode);
1275 1276 1277
	u64 last_len = 0;
	u64 skip = 0;
	u64 defrag_end = 0;
C
Chris Mason 已提交
1278
	u64 newer_off = range->start;
C
Christoph Hellwig 已提交
1279
	unsigned long i;
1280
	unsigned long ra_index = 0;
C
Christoph Hellwig 已提交
1281
	int ret;
C
Chris Mason 已提交
1282
	int defrag_count = 0;
1283
	int compress_type = BTRFS_COMPRESS_ZLIB;
1284
	u32 extent_thresh = range->extent_thresh;
1285
	unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1286
	unsigned long cluster = max_cluster;
1287
	u64 new_align = ~((u64)SZ_128K - 1);
C
Chris Mason 已提交
1288 1289
	struct page **pages = NULL;

1290 1291 1292 1293 1294
	if (isize == 0)
		return 0;

	if (range->start >= isize)
		return -EINVAL;
1295 1296 1297 1298 1299 1300 1301

	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
1302

1303
	if (extent_thresh == 0)
1304
		extent_thresh = SZ_256K;
1305

C
Chris Mason 已提交
1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318
	/*
	 * 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;
	}

1319
	pages = kmalloc_array(max_cluster, sizeof(struct page *),
C
Chris Mason 已提交
1320 1321 1322 1323 1324 1325 1326
			GFP_NOFS);
	if (!pages) {
		ret = -ENOMEM;
		goto out_ra;
	}

	/* find the last page to defrag */
C
Chris Mason 已提交
1327
	if (range->start + range->len > range->start) {
1328
		last_index = min_t(u64, isize - 1,
1329
			 range->start + range->len - 1) >> PAGE_SHIFT;
C
Chris Mason 已提交
1330
	} else {
1331
		last_index = (isize - 1) >> PAGE_SHIFT;
C
Chris Mason 已提交
1332 1333
	}

C
Chris Mason 已提交
1334 1335
	if (newer_than) {
		ret = find_new_extents(root, inode, newer_than,
1336
				       &newer_off, SZ_64K);
C
Chris Mason 已提交
1337 1338 1339 1340 1341 1342
		if (!ret) {
			range->start = newer_off;
			/*
			 * we always align our defrag to help keep
			 * the extents in the file evenly spaced
			 */
1343
			i = (newer_off & new_align) >> PAGE_SHIFT;
C
Chris Mason 已提交
1344 1345 1346
		} else
			goto out_ra;
	} else {
1347
		i = range->start >> PAGE_SHIFT;
C
Chris Mason 已提交
1348 1349
	}
	if (!max_to_defrag)
1350
		max_to_defrag = last_index - i + 1;
C
Chris Mason 已提交
1351

L
Li Zefan 已提交
1352 1353 1354 1355 1356 1357 1358
	/*
	 * 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;

1359
	while (i <= last_index && defrag_count < max_to_defrag &&
1360
	       (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
C
Chris Mason 已提交
1361 1362 1363 1364 1365 1366 1367
		/*
		 * make sure we stop running if someone unmounts
		 * the FS
		 */
		if (!(inode->i_sb->s_flags & MS_ACTIVE))
			break;

1368
		if (btrfs_defrag_cancelled(root->fs_info)) {
1369
			btrfs_debug(root->fs_info, "defrag_file cancelled");
1370 1371 1372 1373
			ret = -EAGAIN;
			break;
		}

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

		if (!newer_than) {
1389 1390
			cluster = (PAGE_ALIGN(defrag_end) >>
				   PAGE_SHIFT) - i;
1391 1392 1393 1394 1395 1396 1397 1398 1399
			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);
1400
			ra_index += cluster;
1401
		}
1402

A
Al Viro 已提交
1403
		inode_lock(inode);
1404 1405
		if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
			BTRFS_I(inode)->force_compress = compress_type;
1406
		ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1407
		if (ret < 0) {
A
Al Viro 已提交
1408
			inode_unlock(inode);
C
Chris Mason 已提交
1409
			goto out_ra;
1410
		}
C
Chris Mason 已提交
1411 1412

		defrag_count += ret;
1413
		balance_dirty_pages_ratelimited(inode->i_mapping);
A
Al Viro 已提交
1414
		inode_unlock(inode);
C
Chris Mason 已提交
1415 1416 1417 1418 1419

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

1420 1421 1422
			if (ret > 0)
				i += ret;

C
Chris Mason 已提交
1423
			newer_off = max(newer_off + 1,
1424
					(u64)i << PAGE_SHIFT);
C
Chris Mason 已提交
1425

1426 1427
			ret = find_new_extents(root, inode, newer_than,
					       &newer_off, SZ_64K);
C
Chris Mason 已提交
1428 1429
			if (!ret) {
				range->start = newer_off;
1430
				i = (newer_off & new_align) >> PAGE_SHIFT;
C
Chris Mason 已提交
1431 1432
			} else {
				break;
C
Christoph Hellwig 已提交
1433
			}
C
Chris Mason 已提交
1434
		} else {
1435
			if (ret > 0) {
L
Li Zefan 已提交
1436
				i += ret;
1437
				last_len += ret << PAGE_SHIFT;
1438
			} else {
L
Li Zefan 已提交
1439
				i++;
1440 1441
				last_len = 0;
			}
C
Christoph Hellwig 已提交
1442 1443 1444
		}
	}

1445
	if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
C
Chris Mason 已提交
1446
		filemap_flush(inode->i_mapping);
1447 1448 1449 1450
		if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
			     &BTRFS_I(inode)->runtime_flags))
			filemap_flush(inode->i_mapping);
	}
C
Chris Mason 已提交
1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466

	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);
	}

1467
	if (range->compress_type == BTRFS_COMPRESS_LZO) {
1468
		btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1469 1470
	}

1471
	ret = defrag_count;
1472

C
Chris Mason 已提交
1473
out_ra:
1474
	if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
A
Al Viro 已提交
1475
		inode_lock(inode);
1476
		BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
A
Al Viro 已提交
1477
		inode_unlock(inode);
1478
	}
C
Chris Mason 已提交
1479 1480 1481
	if (!file)
		kfree(ra);
	kfree(pages);
1482
	return ret;
C
Christoph Hellwig 已提交
1483 1484
}

1485
static noinline int btrfs_ioctl_resize(struct file *file,
1486
					void __user *arg)
C
Christoph Hellwig 已提交
1487 1488 1489 1490
{
	u64 new_size;
	u64 old_size;
	u64 devid = 1;
A
Al Viro 已提交
1491
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
C
Christoph Hellwig 已提交
1492 1493 1494 1495
	struct btrfs_ioctl_vol_args *vol_args;
	struct btrfs_trans_handle *trans;
	struct btrfs_device *device = NULL;
	char *sizestr;
1496
	char *retptr;
C
Christoph Hellwig 已提交
1497 1498 1499 1500
	char *devstr = NULL;
	int ret = 0;
	int mod = 0;

1501 1502 1503
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

1504 1505 1506 1507
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

1508 1509
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
1510
		mnt_drop_write_file(file);
1511
		return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1512 1513
	}

1514
	mutex_lock(&root->fs_info->volume_mutex);
L
Li Zefan 已提交
1515
	vol_args = memdup_user(arg, sizeof(*vol_args));
1516 1517 1518 1519
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
1520 1521

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
1522 1523 1524 1525 1526 1527 1528

	sizestr = vol_args->name;
	devstr = strchr(sizestr, ':');
	if (devstr) {
		sizestr = devstr + 1;
		*devstr = '\0';
		devstr = vol_args->name;
1529 1530 1531
		ret = kstrtoull(devstr, 10, &devid);
		if (ret)
			goto out_free;
1532 1533 1534 1535
		if (!devid) {
			ret = -EINVAL;
			goto out_free;
		}
1536
		btrfs_info(root->fs_info, "resizing devid %llu", devid);
C
Christoph Hellwig 已提交
1537
	}
M
Miao Xie 已提交
1538

1539
	device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
C
Christoph Hellwig 已提交
1540
	if (!device) {
1541
		btrfs_info(root->fs_info, "resizer unable to find device %llu",
1542
		       devid);
1543
		ret = -ENODEV;
1544
		goto out_free;
C
Christoph Hellwig 已提交
1545
	}
M
Miao Xie 已提交
1546 1547

	if (!device->writeable) {
1548 1549
		btrfs_info(root->fs_info,
			   "resizer unable to apply on readonly device %llu",
1550
		       devid);
1551
		ret = -EPERM;
L
Liu Bo 已提交
1552 1553 1554
		goto out_free;
	}

C
Christoph Hellwig 已提交
1555 1556 1557 1558 1559 1560 1561 1562 1563 1564
	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++;
		}
1565 1566
		new_size = memparse(sizestr, &retptr);
		if (*retptr != '\0' || new_size == 0) {
C
Christoph Hellwig 已提交
1567
			ret = -EINVAL;
1568
			goto out_free;
C
Christoph Hellwig 已提交
1569 1570 1571
		}
	}

1572
	if (device->is_tgtdev_for_dev_replace) {
1573
		ret = -EPERM;
1574 1575 1576
		goto out_free;
	}

1577
	old_size = btrfs_device_get_total_bytes(device);
C
Christoph Hellwig 已提交
1578 1579 1580 1581

	if (mod < 0) {
		if (new_size > old_size) {
			ret = -EINVAL;
1582
			goto out_free;
C
Christoph Hellwig 已提交
1583 1584 1585
		}
		new_size = old_size - new_size;
	} else if (mod > 0) {
1586
		if (new_size > ULLONG_MAX - old_size) {
1587
			ret = -ERANGE;
1588 1589
			goto out_free;
		}
C
Christoph Hellwig 已提交
1590 1591 1592
		new_size = old_size + new_size;
	}

1593
	if (new_size < SZ_256M) {
C
Christoph Hellwig 已提交
1594
		ret = -EINVAL;
1595
		goto out_free;
C
Christoph Hellwig 已提交
1596 1597 1598
	}
	if (new_size > device->bdev->bd_inode->i_size) {
		ret = -EFBIG;
1599
		goto out_free;
C
Christoph Hellwig 已提交
1600 1601
	}

1602
	new_size = div_u64(new_size, root->sectorsize);
C
Christoph Hellwig 已提交
1603 1604
	new_size *= root->sectorsize;

1605
	btrfs_info_in_rcu(root->fs_info, "new size for %s is %llu",
1606
		      rcu_str_deref(device->name), new_size);
C
Christoph Hellwig 已提交
1607 1608

	if (new_size > old_size) {
1609
		trans = btrfs_start_transaction(root, 0);
1610 1611
		if (IS_ERR(trans)) {
			ret = PTR_ERR(trans);
1612
			goto out_free;
1613
		}
C
Christoph Hellwig 已提交
1614 1615
		ret = btrfs_grow_device(trans, device, new_size);
		btrfs_commit_transaction(trans, root);
1616
	} else if (new_size < old_size) {
C
Christoph Hellwig 已提交
1617
		ret = btrfs_shrink_device(device, new_size);
1618
	} /* equal, nothing need to do */
C
Christoph Hellwig 已提交
1619

1620
out_free:
C
Christoph Hellwig 已提交
1621
	kfree(vol_args);
1622 1623
out:
	mutex_unlock(&root->fs_info->volume_mutex);
1624
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1625
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
1626 1627 1628
	return ret;
}

S
Sage Weil 已提交
1629
static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
A
Arne Jansen 已提交
1630 1631
				char *name, unsigned long fd, int subvol,
				u64 *transid, bool readonly,
1632
				struct btrfs_qgroup_inherit *inherit)
C
Christoph Hellwig 已提交
1633 1634
{
	int namelen;
1635
	int ret = 0;
C
Christoph Hellwig 已提交
1636

1637 1638 1639 1640
	ret = mnt_want_write_file(file);
	if (ret)
		goto out;

S
Sage Weil 已提交
1641 1642
	namelen = strlen(name);
	if (strchr(name, '/')) {
C
Christoph Hellwig 已提交
1643
		ret = -EINVAL;
1644
		goto out_drop_write;
C
Christoph Hellwig 已提交
1645 1646
	}

1647 1648 1649
	if (name[0] == '.' &&
	   (namelen == 1 || (name[1] == '.' && namelen == 2))) {
		ret = -EEXIST;
1650
		goto out_drop_write;
1651 1652
	}

1653
	if (subvol) {
S
Sage Weil 已提交
1654
		ret = btrfs_mksubvol(&file->f_path, name, namelen,
A
Arne Jansen 已提交
1655
				     NULL, transid, readonly, inherit);
1656
	} else {
1657
		struct fd src = fdget(fd);
1658
		struct inode *src_inode;
1659
		if (!src.file) {
1660
			ret = -EINVAL;
1661
			goto out_drop_write;
1662 1663
		}

A
Al Viro 已提交
1664 1665
		src_inode = file_inode(src.file);
		if (src_inode->i_sb != file_inode(file)->i_sb) {
J
Josef Bacik 已提交
1666
			btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1667
				   "Snapshot src from another FS");
1668
			ret = -EXDEV;
1669 1670 1671 1672 1673 1674
		} else if (!inode_owner_or_capable(src_inode)) {
			/*
			 * Subvolume creation is not restricted, but snapshots
			 * are limited to own subvolumes only
			 */
			ret = -EPERM;
1675 1676 1677 1678
		} else {
			ret = btrfs_mksubvol(&file->f_path, name, namelen,
					     BTRFS_I(src_inode)->root,
					     transid, readonly, inherit);
1679
		}
1680
		fdput(src);
1681
	}
1682 1683
out_drop_write:
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
1684
out:
S
Sage Weil 已提交
1685 1686 1687 1688
	return ret;
}

static noinline int btrfs_ioctl_snap_create(struct file *file,
1689
					    void __user *arg, int subvol)
S
Sage Weil 已提交
1690
{
1691
	struct btrfs_ioctl_vol_args *vol_args;
S
Sage Weil 已提交
1692 1693
	int ret;

1694 1695 1696 1697
	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
1698

1699
	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
L
Li Zefan 已提交
1700
					      vol_args->fd, subvol,
A
Arne Jansen 已提交
1701
					      NULL, false, NULL);
1702

1703 1704 1705
	kfree(vol_args);
	return ret;
}
1706

1707 1708 1709 1710 1711 1712 1713
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
1714
	bool readonly = false;
A
Arne Jansen 已提交
1715
	struct btrfs_qgroup_inherit *inherit = NULL;
1716

1717 1718 1719 1720
	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';
1721

L
Li Zefan 已提交
1722
	if (vol_args->flags &
A
Arne Jansen 已提交
1723 1724
	    ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
	      BTRFS_SUBVOL_QGROUP_INHERIT)) {
L
Li Zefan 已提交
1725
		ret = -EOPNOTSUPP;
D
Dan Carpenter 已提交
1726
		goto free_args;
S
Sage Weil 已提交
1727
	}
1728 1729 1730

	if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
		ptr = &transid;
L
Li Zefan 已提交
1731 1732
	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
		readonly = true;
A
Arne Jansen 已提交
1733
	if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1734
		if (vol_args->size > PAGE_SIZE) {
A
Arne Jansen 已提交
1735
			ret = -EINVAL;
D
Dan Carpenter 已提交
1736
			goto free_args;
A
Arne Jansen 已提交
1737 1738 1739 1740
		}
		inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
		if (IS_ERR(inherit)) {
			ret = PTR_ERR(inherit);
D
Dan Carpenter 已提交
1741
			goto free_args;
A
Arne Jansen 已提交
1742 1743
		}
	}
1744 1745

	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
A
Arne Jansen 已提交
1746
					      vol_args->fd, subvol, ptr,
1747
					      readonly, inherit);
D
Dan Carpenter 已提交
1748 1749
	if (ret)
		goto free_inherit;
1750

D
Dan Carpenter 已提交
1751 1752 1753 1754
	if (ptr && copy_to_user(arg +
				offsetof(struct btrfs_ioctl_vol_args_v2,
					transid),
				ptr, sizeof(*ptr)))
1755
		ret = -EFAULT;
D
Dan Carpenter 已提交
1756 1757

free_inherit:
A
Arne Jansen 已提交
1758
	kfree(inherit);
D
Dan Carpenter 已提交
1759 1760
free_args:
	kfree(vol_args);
C
Christoph Hellwig 已提交
1761 1762 1763
	return ret;
}

1764 1765 1766
static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
						void __user *arg)
{
A
Al Viro 已提交
1767
	struct inode *inode = file_inode(file);
1768 1769 1770 1771
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret = 0;
	u64 flags = 0;

L
Li Zefan 已提交
1772
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788
		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
1789
	struct inode *inode = file_inode(file);
1790 1791 1792 1793 1794 1795
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
	u64 root_flags;
	u64 flags;
	int ret = 0;

1796 1797 1798
	if (!inode_owner_or_capable(inode))
		return -EPERM;

1799 1800 1801
	ret = mnt_want_write_file(file);
	if (ret)
		goto out;
1802

1803 1804 1805 1806
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
		ret = -EINVAL;
		goto out_drop_write;
	}
1807

1808 1809 1810 1811
	if (copy_from_user(&flags, arg, sizeof(flags))) {
		ret = -EFAULT;
		goto out_drop_write;
	}
1812

1813 1814 1815 1816
	if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
		ret = -EINVAL;
		goto out_drop_write;
	}
1817

1818 1819 1820 1821
	if (flags & ~BTRFS_SUBVOL_RDONLY) {
		ret = -EOPNOTSUPP;
		goto out_drop_write;
	}
1822 1823 1824 1825 1826

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

	/* nothing to do */
	if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1827
		goto out_drop_sem;
1828 1829

	root_flags = btrfs_root_flags(&root->root_item);
1830
	if (flags & BTRFS_SUBVOL_RDONLY) {
1831 1832
		btrfs_set_root_flags(&root->root_item,
				     root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1833 1834 1835 1836 1837 1838 1839 1840
	} 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,
1841
				     root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1842 1843 1844 1845 1846 1847 1848 1849 1850 1851
			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;
		}
	}
1852 1853 1854 1855 1856 1857 1858

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

1859
	ret = btrfs_update_root(trans, root->fs_info->tree_root,
1860 1861 1862 1863 1864 1865
				&root->root_key, &root->root_item);

	btrfs_commit_transaction(trans, root);
out_reset:
	if (ret)
		btrfs_set_root_flags(&root->root_item, root_flags);
1866
out_drop_sem:
1867
	up_write(&root->fs_info->subvol_sem);
1868 1869 1870
out_drop_write:
	mnt_drop_write_file(file);
out:
1871 1872 1873
	return ret;
}

1874 1875 1876 1877 1878 1879
/*
 * helper to check if the subvolume references other subvolumes
 */
static noinline int may_destroy_subvol(struct btrfs_root *root)
{
	struct btrfs_path *path;
1880
	struct btrfs_dir_item *di;
1881
	struct btrfs_key key;
1882
	u64 dir_id;
1883 1884 1885 1886 1887 1888
	int ret;

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

1889 1890 1891 1892 1893 1894 1895
	/* 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) {
1896 1897 1898
			ret = -EPERM;
			btrfs_err(root->fs_info, "deleting default subvolume "
				  "%llu is not allowed", key.objectid);
1899 1900 1901 1902 1903
			goto out;
		}
		btrfs_release_path(path);
	}

1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926
	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;
}

1927 1928 1929
static noinline int key_in_sk(struct btrfs_key *key,
			      struct btrfs_ioctl_search_key *sk)
{
1930 1931 1932 1933 1934 1935 1936 1937 1938
	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)
1939
		return 0;
1940 1941 1942 1943 1944 1945 1946

	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)
1947 1948 1949 1950 1951 1952 1953 1954
		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,
1955
			       size_t *buf_size,
1956
			       char __user *ubuf,
1957 1958 1959 1960 1961 1962
			       unsigned long *sk_offset,
			       int *num_found)
{
	u64 found_transid;
	struct extent_buffer *leaf;
	struct btrfs_ioctl_search_header sh;
1963
	struct btrfs_key test;
1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984
	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);

1985 1986 1987 1988
		btrfs_item_key_to_cpu(leaf, key, i);
		if (!key_in_sk(key, sk))
			continue;

1989
		if (sizeof(sh) + item_len > *buf_size) {
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
			if (*num_found) {
				ret = 1;
				goto out;
			}

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

2000
			*buf_size = sizeof(sh) + item_len;
2001
			item_len = 0;
2002 2003
			ret = -EOVERFLOW;
		}
2004

2005
		if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2006
			ret = 1;
2007
			goto out;
2008 2009 2010 2011 2012 2013 2014 2015 2016
		}

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

		/* copy search result header */
2017 2018 2019 2020 2021
		if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
			ret = -EFAULT;
			goto out;
		}

2022 2023 2024
		*sk_offset += sizeof(sh);

		if (item_len) {
2025
			char __user *up = ubuf + *sk_offset;
2026
			/* copy the item */
2027 2028 2029 2030 2031 2032
			if (read_extent_buffer_to_user(leaf, up,
						       item_off, item_len)) {
				ret = -EFAULT;
				goto out;
			}

2033 2034
			*sk_offset += item_len;
		}
2035
		(*num_found)++;
2036

2037 2038 2039
		if (ret) /* -EOVERFLOW from above */
			goto out;

2040 2041 2042 2043
		if (*num_found >= sk->nr_items) {
			ret = 1;
			goto out;
		}
2044 2045
	}
advance_key:
2046
	ret = 0;
2047 2048 2049 2050 2051 2052
	test.objectid = sk->max_objectid;
	test.type = sk->max_type;
	test.offset = sk->max_offset;
	if (btrfs_comp_cpu_keys(key, &test) >= 0)
		ret = 1;
	else if (key->offset < (u64)-1)
2053
		key->offset++;
2054
	else if (key->type < (u8)-1) {
2055
		key->offset = 0;
2056
		key->type++;
2057
	} else if (key->objectid < (u64)-1) {
2058 2059
		key->offset = 0;
		key->type = 0;
2060
		key->objectid++;
2061 2062
	} else
		ret = 1;
2063
out:
2064 2065 2066 2067 2068 2069 2070 2071 2072
	/*
	 *  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
	 */
2073 2074 2075 2076
	return ret;
}

static noinline int search_ioctl(struct inode *inode,
2077
				 struct btrfs_ioctl_search_key *sk,
2078
				 size_t *buf_size,
2079
				 char __user *ubuf)
2080 2081 2082 2083 2084 2085 2086 2087 2088
{
	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;

2089 2090
	if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
		*buf_size = sizeof(struct btrfs_ioctl_search_header);
2091
		return -EOVERFLOW;
2092
	}
2093

2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115
	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

	if (sk->tree_id == 0) {
		/* search the root of the inode that was passed */
		root = BTRFS_I(inode)->root;
	} else {
		key.objectid = sk->tree_id;
		key.type = BTRFS_ROOT_ITEM_KEY;
		key.offset = (u64)-1;
		root = btrfs_read_fs_root_no_name(info, &key);
		if (IS_ERR(root)) {
			btrfs_free_path(path);
			return -ENOENT;
		}
	}

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

2116
	while (1) {
2117
		ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2118 2119 2120 2121 2122
		if (ret != 0) {
			if (ret > 0)
				ret = 0;
			goto err;
		}
2123
		ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2124
				 &sk_offset, &num_found);
2125
		btrfs_release_path(path);
2126
		if (ret)
2127 2128 2129
			break;

	}
2130 2131
	if (ret > 0)
		ret = 0;
2132 2133 2134 2135 2136 2137 2138 2139 2140
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)
{
2141 2142
	struct btrfs_ioctl_search_args __user *uargs;
	struct btrfs_ioctl_search_key sk;
2143 2144 2145
	struct inode *inode;
	int ret;
	size_t buf_size;
2146 2147 2148 2149

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

2150 2151 2152 2153
	uargs = (struct btrfs_ioctl_search_args __user *)argp;

	if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
		return -EFAULT;
2154

2155
	buf_size = sizeof(uargs->buf);
2156

A
Al Viro 已提交
2157
	inode = file_inode(file);
2158
	ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2159 2160 2161 2162 2163 2164 2165 2166

	/*
	 * 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;

2167
	if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2168 2169 2170 2171
		ret = -EFAULT;
	return ret;
}

G
Gerhard Heift 已提交
2172 2173 2174 2175 2176 2177 2178 2179
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;
2180
	const size_t buf_limit = SZ_16M;
G
Gerhard Heift 已提交
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

	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;

2208 2209 2210
	return ret;
}

2211
/*
2212 2213 2214
 * Search INODE_REFs to identify path name of 'dirid' directory
 * in a 'tree_id' tree. and sets path name to 'name'.
 */
2215 2216 2217 2218 2219
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;
2220
	char *ptr;
2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237
	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;

2238
	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2239 2240 2241 2242 2243 2244

	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)) {
2245
		btrfs_err(info, "could not find root %llu", tree_id);
2246 2247
		ret = -ENOENT;
		goto out;
2248 2249 2250 2251
	}

	key.objectid = dirid;
	key.type = BTRFS_INODE_REF_KEY;
2252
	key.offset = (u64)-1;
2253

2254
	while (1) {
2255 2256 2257
		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
		if (ret < 0)
			goto out;
2258 2259 2260 2261 2262 2263 2264 2265 2266 2267
		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;
			}
		}
2268 2269 2270 2271 2272 2273 2274 2275 2276

		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;
2277 2278
		if (ptr < name) {
			ret = -ENAMETOOLONG;
2279
			goto out;
2280
		}
2281 2282

		*(ptr + len) = '/';
2283
		read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2284 2285 2286 2287

		if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
			break;

2288
		btrfs_release_path(path);
2289
		key.objectid = key.offset;
2290
		key.offset = (u64)-1;
2291 2292
		dirid = key.objectid;
	}
2293
	memmove(name, ptr, total_len);
2294
	name[total_len] = '\0';
2295 2296 2297
	ret = 0;
out:
	btrfs_free_path(path);
2298 2299 2300 2301 2302 2303 2304 2305
	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;
2306
	int ret = 0;
2307

J
Julia Lawall 已提交
2308 2309 2310
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
2311

A
Al Viro 已提交
2312
	inode = file_inode(file);
2313

2314 2315 2316 2317
	/*
	 * Unprivileged query to obtain the containing subvolume root id. The
	 * path is reset so it's consistent with btrfs_search_path_in_tree.
	 */
2318 2319 2320
	if (args->treeid == 0)
		args->treeid = BTRFS_I(inode)->root->root_key.objectid;

2321 2322 2323 2324 2325 2326 2327 2328 2329 2330
	if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
		args->name[0] = 0;
		goto out;
	}

	if (!capable(CAP_SYS_ADMIN)) {
		ret = -EPERM;
		goto out;
	}

2331 2332 2333 2334
	ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
					args->treeid, args->objectid,
					args->name);

2335
out:
2336 2337 2338 2339
	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
		ret = -EFAULT;

	kfree(args);
2340 2341 2342
	return ret;
}

2343 2344 2345
static noinline int btrfs_ioctl_snap_destroy(struct file *file,
					     void __user *arg)
{
A
Al Viro 已提交
2346
	struct dentry *parent = file->f_path.dentry;
2347
	struct dentry *dentry;
2348
	struct inode *dir = d_inode(parent);
2349 2350 2351 2352 2353
	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;
2354
	struct btrfs_block_rsv block_rsv;
2355
	u64 root_flags;
2356
	u64 qgroup_reserved;
2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372
	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;
	}

2373
	err = mnt_want_write_file(file);
2374 2375 2376
	if (err)
		goto out;

2377

2378 2379 2380
	err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
	if (err == -EINTR)
		goto out_drop_write;
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;
	}

2387
	if (d_really_is_negative(dentry)) {
2388 2389 2390 2391
		err = -ENOENT;
		goto out_dput;
	}

2392
	inode = d_inode(dentry);
2393
	dest = BTRFS_I(inode)->root;
2394
	if (!capable(CAP_SYS_ADMIN)) {
2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408
		/*
		 * 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;
2409
		if (!btrfs_test_opt(root->fs_info, USER_SUBVOL_RM_ALLOWED))
2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427
			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;
	}

2428 2429 2430 2431 2432
	/* 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
2433
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2434 2435 2436 2437
		err = -EINVAL;
		goto out_dput;
	}

A
Al Viro 已提交
2438
	inode_lock(inode);
2439 2440 2441 2442 2443 2444 2445

	/*
	 * 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);
2446 2447 2448
	root_flags = btrfs_root_flags(&dest->root_item);
	if (dest->send_in_progress == 0) {
		btrfs_set_root_flags(&dest->root_item,
2449 2450 2451 2452 2453 2454
				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",
2455
			dest->root_key.objectid);
2456
		err = -EPERM;
2457
		goto out_unlock_inode;
2458 2459
	}

2460 2461 2462 2463 2464 2465
	down_write(&root->fs_info->subvol_sem);

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

2466 2467 2468 2469 2470 2471
	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,
2472
					       5, &qgroup_reserved, true);
2473 2474 2475
	if (err)
		goto out_up_write;

2476 2477 2478
	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		err = PTR_ERR(trans);
2479
		goto out_release;
2480
	}
2481 2482
	trans->block_rsv = &block_rsv;
	trans->bytes_reserved = block_rsv.size;
2483

2484 2485
	btrfs_record_snapshot_destroy(trans, dir);

2486 2487 2488 2489
	ret = btrfs_unlink_subvol(trans, root, dir,
				dest->root_key.objectid,
				dentry->d_name.name,
				dentry->d_name.len);
2490 2491 2492 2493 2494
	if (ret) {
		err = ret;
		btrfs_abort_transaction(trans, root, ret);
		goto out_end_trans;
	}
2495 2496 2497 2498 2499 2500 2501 2502

	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);

2503
	if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2504 2505 2506
		ret = btrfs_insert_orphan_item(trans,
					root->fs_info->tree_root,
					dest->root_key.objectid);
2507 2508 2509 2510 2511
		if (ret) {
			btrfs_abort_transaction(trans, root, ret);
			err = ret;
			goto out_end_trans;
		}
2512
	}
2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533

	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;
		}
	}

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

		/* the last ref */
2561 2562 2563
		if (dest->ino_cache_inode) {
			iput(dest->ino_cache_inode);
			dest->ino_cache_inode = NULL;
2564
		}
2565 2566 2567 2568
	}
out_dput:
	dput(dentry);
out_unlock_dir:
A
Al Viro 已提交
2569
	inode_unlock(dir);
2570
out_drop_write:
A
Al Viro 已提交
2571
	mnt_drop_write_file(file);
2572 2573 2574 2575 2576
out:
	kfree(vol_args);
	return err;
}

C
Chris Mason 已提交
2577
static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
C
Christoph Hellwig 已提交
2578
{
A
Al Viro 已提交
2579
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
2580
	struct btrfs_root *root = BTRFS_I(inode)->root;
C
Chris Mason 已提交
2581
	struct btrfs_ioctl_defrag_range_args *range;
Y
Yan Zheng 已提交
2582 2583
	int ret;

2584 2585 2586
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
L
Li Zefan 已提交
2587

2588 2589 2590
	if (btrfs_root_readonly(root)) {
		ret = -EROFS;
		goto out;
2591
	}
C
Christoph Hellwig 已提交
2592 2593 2594

	switch (inode->i_mode & S_IFMT) {
	case S_IFDIR:
2595 2596 2597 2598
		if (!capable(CAP_SYS_ADMIN)) {
			ret = -EPERM;
			goto out;
		}
2599
		ret = btrfs_defrag_root(root);
2600 2601
		if (ret)
			goto out;
2602
		ret = btrfs_defrag_root(root->fs_info->extent_root);
C
Christoph Hellwig 已提交
2603 2604
		break;
	case S_IFREG:
2605 2606 2607 2608
		if (!(file->f_mode & FMODE_WRITE)) {
			ret = -EINVAL;
			goto out;
		}
C
Chris Mason 已提交
2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620

		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);
2621
				goto out;
C
Chris Mason 已提交
2622 2623 2624 2625 2626 2627 2628 2629 2630 2631
			}
			/* 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
2632
		ret = btrfs_defrag_file(file_inode(file), file,
C
Chris Mason 已提交
2633 2634 2635
					range, 0, 0);
		if (ret > 0)
			ret = 0;
C
Chris Mason 已提交
2636
		kfree(range);
C
Christoph Hellwig 已提交
2637
		break;
2638 2639
	default:
		ret = -EINVAL;
C
Christoph Hellwig 已提交
2640
	}
2641
out:
2642
	mnt_drop_write_file(file);
2643
	return ret;
C
Christoph Hellwig 已提交
2644 2645
}

2646
static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
2647 2648 2649 2650
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

2651 2652 2653
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2654 2655
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
2656
		return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2657 2658
	}

2659
	mutex_lock(&root->fs_info->volume_mutex);
L
Li Zefan 已提交
2660
	vol_args = memdup_user(arg, sizeof(*vol_args));
2661 2662 2663 2664
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
C
Christoph Hellwig 已提交
2665

2666
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
2667 2668
	ret = btrfs_init_new_device(root, vol_args->name);

A
Anand Jain 已提交
2669 2670 2671
	if (!ret)
		btrfs_info(root->fs_info, "disk added %s",vol_args->name);

C
Christoph Hellwig 已提交
2672
	kfree(vol_args);
2673 2674
out:
	mutex_unlock(&root->fs_info->volume_mutex);
2675
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
C
Christoph Hellwig 已提交
2676 2677 2678
	return ret;
}

2679
static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
C
Christoph Hellwig 已提交
2680
{
A
Al Viro 已提交
2681
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2682
	struct btrfs_ioctl_vol_args_v2 *vol_args;
C
Christoph Hellwig 已提交
2683 2684
	int ret;

2685 2686 2687
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2688 2689 2690
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
Y
Yan Zheng 已提交
2691

L
Li Zefan 已提交
2692
	vol_args = memdup_user(arg, sizeof(*vol_args));
2693 2694
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
D
Dan Carpenter 已提交
2695
		goto err_drop;
2696
	}
C
Christoph Hellwig 已提交
2697

2698
	/* Check for compatibility reject unknown flags */
2699 2700
	if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED)
		return -EOPNOTSUPP;
C
Christoph Hellwig 已提交
2701

2702 2703 2704 2705 2706 2707 2708
	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);
2709
	if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
2710 2711 2712 2713 2714
		ret = btrfs_rm_device(root, NULL, vol_args->devid);
	} else {
		vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
		ret = btrfs_rm_device(root, vol_args->name, 0);
	}
2715
	mutex_unlock(&root->fs_info->volume_mutex);
2716
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2717

2718
	if (!ret) {
2719
		if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
2720 2721 2722 2723 2724 2725
			btrfs_info(root->fs_info, "device deleted: id %llu",
					vol_args->devid);
		else
			btrfs_info(root->fs_info, "device deleted: %s",
					vol_args->name);
	}
2726 2727
out:
	kfree(vol_args);
D
Dan Carpenter 已提交
2728
err_drop:
2729
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
2730 2731 2732
	return ret;
}

2733
static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
C
Christoph Hellwig 已提交
2734
{
A
Al Viro 已提交
2735
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
C
Christoph Hellwig 已提交
2736 2737 2738
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

2739 2740 2741
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2742 2743 2744
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
Y
Yan Zheng 已提交
2745

2746 2747 2748
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2749 2750 2751 2752 2753 2754
		goto out_drop_write;
	}

	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
2755 2756 2757
		goto out;
	}

2758
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2759
	mutex_lock(&root->fs_info->volume_mutex);
2760
	ret = btrfs_rm_device(root, vol_args->name, 0);
2761
	mutex_unlock(&root->fs_info->volume_mutex);
2762

2763 2764
	if (!ret)
		btrfs_info(root->fs_info, "disk deleted %s",vol_args->name);
2765
	kfree(vol_args);
2766 2767 2768
out:
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
out_drop_write:
2769
	mnt_drop_write_file(file);
2770

C
Christoph Hellwig 已提交
2771 2772 2773
	return ret;
}

J
Jan Schmidt 已提交
2774 2775
static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
{
2776
	struct btrfs_ioctl_fs_info_args *fi_args;
J
Jan Schmidt 已提交
2777 2778
	struct btrfs_device *device;
	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2779
	int ret = 0;
J
Jan Schmidt 已提交
2780

2781 2782 2783 2784
	fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
	if (!fi_args)
		return -ENOMEM;

2785
	mutex_lock(&fs_devices->device_list_mutex);
2786 2787
	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
2788

2789
	list_for_each_entry(device, &fs_devices->devices, dev_list) {
2790 2791
		if (device->devid > fi_args->max_id)
			fi_args->max_id = device->devid;
J
Jan Schmidt 已提交
2792 2793 2794
	}
	mutex_unlock(&fs_devices->device_list_mutex);

2795 2796 2797 2798
	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;

2799 2800
	if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
		ret = -EFAULT;
J
Jan Schmidt 已提交
2801

2802 2803
	kfree(fi_args);
	return ret;
J
Jan Schmidt 已提交
2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817
}

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);

2818
	if (!btrfs_is_empty_uuid(di_args->uuid))
J
Jan Schmidt 已提交
2819 2820 2821
		s_uuid = di_args->uuid;

	mutex_lock(&fs_devices->device_list_mutex);
2822
	dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
J
Jan Schmidt 已提交
2823 2824 2825 2826 2827 2828 2829

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

	di_args->devid = dev->devid;
2830 2831
	di_args->bytes_used = btrfs_device_get_bytes_used(dev);
	di_args->total_bytes = btrfs_device_get_total_bytes(dev);
J
Jan Schmidt 已提交
2832
	memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2833
	if (dev->name) {
2834 2835 2836 2837 2838 2839
		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();
2840 2841
		di_args->path[sizeof(di_args->path) - 1] = 0;
	} else {
2842
		di_args->path[0] = '\0';
2843
	}
J
Jan Schmidt 已提交
2844 2845

out:
2846
	mutex_unlock(&fs_devices->device_list_mutex);
J
Jan Schmidt 已提交
2847 2848 2849 2850 2851 2852 2853
	if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
		ret = -EFAULT;

	kfree(di_args);
	return ret;
}

2854
static struct page *extent_same_get_page(struct inode *inode, pgoff_t index)
M
Mark Fasheh 已提交
2855 2856 2857 2858 2859
{
	struct page *page;

	page = grab_cache_page(inode->i_mapping, index);
	if (!page)
2860
		return ERR_PTR(-ENOMEM);
M
Mark Fasheh 已提交
2861 2862

	if (!PageUptodate(page)) {
2863 2864 2865 2866 2867
		int ret;

		ret = btrfs_readpage(NULL, page);
		if (ret)
			return ERR_PTR(ret);
M
Mark Fasheh 已提交
2868 2869 2870
		lock_page(page);
		if (!PageUptodate(page)) {
			unlock_page(page);
2871
			put_page(page);
2872 2873 2874 2875
			return ERR_PTR(-EIO);
		}
		if (page->mapping != inode->i_mapping) {
			unlock_page(page);
2876
			put_page(page);
2877
			return ERR_PTR(-EAGAIN);
M
Mark Fasheh 已提交
2878 2879 2880 2881 2882 2883
		}
	}

	return page;
}

2884 2885 2886 2887
static int gather_extent_pages(struct inode *inode, struct page **pages,
			       int num_pages, u64 off)
{
	int i;
2888
	pgoff_t index = off >> PAGE_SHIFT;
2889 2890

	for (i = 0; i < num_pages; i++) {
2891
again:
2892
		pages[i] = extent_same_get_page(inode, index + i);
2893 2894 2895 2896 2897 2898 2899 2900
		if (IS_ERR(pages[i])) {
			int err = PTR_ERR(pages[i]);

			if (err == -EAGAIN)
				goto again;
			pages[i] = NULL;
			return err;
		}
2901 2902 2903 2904
	}
	return 0;
}

2905 2906
static int lock_extent_range(struct inode *inode, u64 off, u64 len,
			     bool retry_range_locking)
2907
{
2908 2909 2910 2911 2912 2913 2914 2915
	/*
	 * Do any pending delalloc/csum calculations on inode, one way or
	 * another, and lock file content.
	 * The locking order is:
	 *
	 *   1) pages
	 *   2) range in the inode's io tree
	 */
2916 2917 2918 2919 2920
	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);
2921 2922 2923
		if ((!ordered ||
		     ordered->file_offset + ordered->len <= off ||
		     ordered->file_offset >= off + len) &&
2924
		    !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2925 2926 2927
				    off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
			if (ordered)
				btrfs_put_ordered_extent(ordered);
2928
			break;
2929
		}
2930 2931 2932
		unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
		if (ordered)
			btrfs_put_ordered_extent(ordered);
2933 2934
		if (!retry_range_locking)
			return -EAGAIN;
2935 2936
		btrfs_wait_ordered_range(inode, off, len);
	}
2937
	return 0;
2938 2939
}

2940
static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2)
M
Mark Fasheh 已提交
2941
{
A
Al Viro 已提交
2942 2943
	inode_unlock(inode1);
	inode_unlock(inode2);
M
Mark Fasheh 已提交
2944 2945
}

2946 2947 2948 2949 2950
static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
{
	if (inode1 < inode2)
		swap(inode1, inode2);

A
Al Viro 已提交
2951 2952
	inode_lock_nested(inode1, I_MUTEX_PARENT);
	inode_lock_nested(inode2, I_MUTEX_CHILD);
2953 2954 2955 2956 2957 2958 2959 2960 2961
}

static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
				      struct inode *inode2, u64 loff2, u64 len)
{
	unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
	unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
}

2962 2963 2964
static int btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
				    struct inode *inode2, u64 loff2, u64 len,
				    bool retry_range_locking)
M
Mark Fasheh 已提交
2965
{
2966 2967
	int ret;

M
Mark Fasheh 已提交
2968 2969 2970 2971
	if (inode1 < inode2) {
		swap(inode1, inode2);
		swap(loff1, loff2);
	}
2972 2973 2974 2975 2976 2977 2978 2979
	ret = lock_extent_range(inode1, loff1, len, retry_range_locking);
	if (ret)
		return ret;
	ret = lock_extent_range(inode2, loff2, len, retry_range_locking);
	if (ret)
		unlock_extent(&BTRFS_I(inode1)->io_tree, loff1,
			      loff1 + len - 1);
	return ret;
2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994
}

struct cmp_pages {
	int		num_pages;
	struct page	**src_pages;
	struct page	**dst_pages;
};

static void btrfs_cmp_data_free(struct cmp_pages *cmp)
{
	int i;
	struct page *pg;

	for (i = 0; i < cmp->num_pages; i++) {
		pg = cmp->src_pages[i];
2995 2996
		if (pg) {
			unlock_page(pg);
2997
			put_page(pg);
2998
		}
2999
		pg = cmp->dst_pages[i];
3000 3001
		if (pg) {
			unlock_page(pg);
3002
			put_page(pg);
3003
		}
3004 3005 3006 3007 3008 3009 3010 3011 3012 3013
	}
	kfree(cmp->src_pages);
	kfree(cmp->dst_pages);
}

static int btrfs_cmp_data_prepare(struct inode *src, u64 loff,
				  struct inode *dst, u64 dst_loff,
				  u64 len, struct cmp_pages *cmp)
{
	int ret;
3014
	int num_pages = PAGE_ALIGN(len) >> PAGE_SHIFT;
3015 3016 3017 3018 3019 3020 3021 3022
	struct page **src_pgarr, **dst_pgarr;

	/*
	 * We must gather up all the pages before we initiate our
	 * extent locking. We use an array for the page pointers. Size
	 * of the array is bounded by len, which is in turn bounded by
	 * BTRFS_MAX_DEDUPE_LEN.
	 */
3023 3024
	src_pgarr = kcalloc(num_pages, sizeof(struct page *), GFP_KERNEL);
	dst_pgarr = kcalloc(num_pages, sizeof(struct page *), GFP_KERNEL);
3025 3026 3027 3028
	if (!src_pgarr || !dst_pgarr) {
		kfree(src_pgarr);
		kfree(dst_pgarr);
		return -ENOMEM;
M
Mark Fasheh 已提交
3029
	}
3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043
	cmp->num_pages = num_pages;
	cmp->src_pages = src_pgarr;
	cmp->dst_pages = dst_pgarr;

	ret = gather_extent_pages(src, cmp->src_pages, cmp->num_pages, loff);
	if (ret)
		goto out;

	ret = gather_extent_pages(dst, cmp->dst_pages, cmp->num_pages, dst_loff);

out:
	if (ret)
		btrfs_cmp_data_free(cmp);
	return 0;
M
Mark Fasheh 已提交
3044 3045 3046
}

static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
3047
			  u64 dst_loff, u64 len, struct cmp_pages *cmp)
M
Mark Fasheh 已提交
3048 3049
{
	int ret = 0;
3050
	int i;
M
Mark Fasheh 已提交
3051
	struct page *src_page, *dst_page;
3052
	unsigned int cmp_len = PAGE_SIZE;
M
Mark Fasheh 已提交
3053 3054
	void *addr, *dst_addr;

3055
	i = 0;
M
Mark Fasheh 已提交
3056
	while (len) {
3057
		if (len < PAGE_SIZE)
M
Mark Fasheh 已提交
3058 3059
			cmp_len = len;

3060 3061 3062 3063
		BUG_ON(i >= cmp->num_pages);

		src_page = cmp->src_pages[i];
		dst_page = cmp->dst_pages[i];
3064 3065
		ASSERT(PageLocked(src_page));
		ASSERT(PageLocked(dst_page));
3066

M
Mark Fasheh 已提交
3067 3068 3069 3070 3071 3072 3073
		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))
3074
			ret = -EBADE;
M
Mark Fasheh 已提交
3075 3076 3077 3078 3079 3080 3081 3082

		kunmap_atomic(addr);
		kunmap_atomic(dst_addr);

		if (ret)
			break;

		len -= cmp_len;
3083
		i++;
M
Mark Fasheh 已提交
3084 3085 3086 3087 3088
	}

	return ret;
}

3089 3090
static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen,
				     u64 olen)
M
Mark Fasheh 已提交
3091
{
3092
	u64 len = *plen;
M
Mark Fasheh 已提交
3093 3094
	u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;

3095
	if (off + olen > inode->i_size || off + olen < off)
M
Mark Fasheh 已提交
3096
		return -EINVAL;
3097 3098 3099 3100 3101

	/* if we extend to eof, continue to block boundary */
	if (off + len == inode->i_size)
		*plen = len = ALIGN(inode->i_size, bs) - off;

M
Mark Fasheh 已提交
3102 3103 3104 3105 3106 3107 3108
	/* Check that we are block aligned - btrfs_clone() requires this */
	if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
		return -EINVAL;

	return 0;
}

3109
static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
M
Mark Fasheh 已提交
3110 3111 3112
			     struct inode *dst, u64 dst_loff)
{
	int ret;
3113
	u64 len = olen;
3114
	struct cmp_pages cmp;
M
Mark Fasheh 已提交
3115 3116 3117
	int same_inode = 0;
	u64 same_lock_start = 0;
	u64 same_lock_len = 0;
M
Mark Fasheh 已提交
3118 3119

	if (src == dst)
M
Mark Fasheh 已提交
3120
		same_inode = 1;
M
Mark Fasheh 已提交
3121

3122 3123 3124
	if (len == 0)
		return 0;

M
Mark Fasheh 已提交
3125
	if (same_inode) {
A
Al Viro 已提交
3126
		inode_lock(src);
M
Mark Fasheh 已提交
3127

M
Mark Fasheh 已提交
3128
		ret = extent_same_check_offsets(src, loff, &len, olen);
3129 3130 3131
		if (ret)
			goto out_unlock;
		ret = extent_same_check_offsets(src, dst_loff, &len, olen);
M
Mark Fasheh 已提交
3132 3133
		if (ret)
			goto out_unlock;
M
Mark Fasheh 已提交
3134

M
Mark Fasheh 已提交
3135 3136 3137 3138 3139 3140 3141 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
		/*
		 * Single inode case wants the same checks, except we
		 * don't want our length pushed out past i_size as
		 * comparing that data range makes no sense.
		 *
		 * extent_same_check_offsets() will do this for an
		 * unaligned length at i_size, so catch it here and
		 * reject the request.
		 *
		 * This effectively means we require aligned extents
		 * for the single-inode case, whereas the other cases
		 * allow an unaligned length so long as it ends at
		 * i_size.
		 */
		if (len != olen) {
			ret = -EINVAL;
			goto out_unlock;
		}

		/* Check for overlapping ranges */
		if (dst_loff + len > loff && dst_loff < loff + len) {
			ret = -EINVAL;
			goto out_unlock;
		}

		same_lock_start = min_t(u64, loff, dst_loff);
		same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start;
	} else {
		btrfs_double_inode_lock(src, dst);

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

		ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
		if (ret)
			goto out_unlock;
	}
M
Mark Fasheh 已提交
3173 3174 3175 3176 3177 3178 3179 3180

	/* 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;
	}

3181
again:
3182 3183 3184 3185
	ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, &cmp);
	if (ret)
		goto out_unlock;

M
Mark Fasheh 已提交
3186
	if (same_inode)
3187 3188
		ret = lock_extent_range(src, same_lock_start, same_lock_len,
					false);
M
Mark Fasheh 已提交
3189
	else
3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220
		ret = btrfs_double_extent_lock(src, loff, dst, dst_loff, len,
					       false);
	/*
	 * If one of the inodes has dirty pages in the respective range or
	 * ordered extents, we need to flush dellaloc and wait for all ordered
	 * extents in the range. We must unlock the pages and the ranges in the
	 * io trees to avoid deadlocks when flushing delalloc (requires locking
	 * pages) and when waiting for ordered extents to complete (they require
	 * range locking).
	 */
	if (ret == -EAGAIN) {
		/*
		 * Ranges in the io trees already unlocked. Now unlock all
		 * pages before waiting for all IO to complete.
		 */
		btrfs_cmp_data_free(&cmp);
		if (same_inode) {
			btrfs_wait_ordered_range(src, same_lock_start,
						 same_lock_len);
		} else {
			btrfs_wait_ordered_range(src, loff, len);
			btrfs_wait_ordered_range(dst, dst_loff, len);
		}
		goto again;
	}
	ASSERT(ret == 0);
	if (WARN_ON(ret)) {
		/* ranges in the io trees already unlocked */
		btrfs_cmp_data_free(&cmp);
		return ret;
	}
3221

3222
	/* pass original length for comparison so we stay within i_size */
3223
	ret = btrfs_cmp_data(src, loff, dst, dst_loff, olen, &cmp);
M
Mark Fasheh 已提交
3224
	if (ret == 0)
3225
		ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1);
M
Mark Fasheh 已提交
3226

M
Mark Fasheh 已提交
3227 3228 3229 3230 3231
	if (same_inode)
		unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start,
			      same_lock_start + same_lock_len - 1);
	else
		btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
3232 3233

	btrfs_cmp_data_free(&cmp);
M
Mark Fasheh 已提交
3234
out_unlock:
M
Mark Fasheh 已提交
3235
	if (same_inode)
A
Al Viro 已提交
3236
		inode_unlock(src);
M
Mark Fasheh 已提交
3237 3238
	else
		btrfs_double_inode_unlock(src, dst);
M
Mark Fasheh 已提交
3239 3240 3241 3242

	return ret;
}

3243
#define BTRFS_MAX_DEDUPE_LEN	SZ_16M
M
Mark Fasheh 已提交
3244

3245 3246
ssize_t btrfs_dedupe_file_range(struct file *src_file, u64 loff, u64 olen,
				struct file *dst_file, u64 dst_loff)
M
Mark Fasheh 已提交
3247
{
3248 3249
	struct inode *src = file_inode(src_file);
	struct inode *dst = file_inode(dst_file);
M
Mark Fasheh 已提交
3250
	u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
3251
	ssize_t res;
M
Mark Fasheh 已提交
3252

3253 3254
	if (olen > BTRFS_MAX_DEDUPE_LEN)
		olen = BTRFS_MAX_DEDUPE_LEN;
M
Mark Fasheh 已提交
3255

3256
	if (WARN_ON_ONCE(bs < PAGE_SIZE)) {
M
Mark Fasheh 已提交
3257 3258 3259 3260 3261
		/*
		 * Btrfs does not support blocksize < page_size. As a
		 * result, btrfs_cmp_data() won't correctly handle
		 * this situation without an update.
		 */
3262
		return -EINVAL;
M
Mark Fasheh 已提交
3263 3264
	}

3265 3266 3267 3268
	res = btrfs_extent_same(src, loff, olen, dst, dst_loff);
	if (res)
		return res;
	return olen;
M
Mark Fasheh 已提交
3269 3270
}

3271 3272 3273 3274
static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
				     struct inode *inode,
				     u64 endoff,
				     const u64 destoff,
3275 3276
				     const u64 olen,
				     int no_time_update)
3277 3278 3279 3280 3281
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret;

	inode_inc_iversion(inode);
3282
	if (!no_time_update)
3283
		inode->i_mtime = inode->i_ctime = current_fs_time(inode->i_sb);
3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303
	/*
	 * 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;
}

3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320
static void clone_update_extent_map(struct inode *inode,
				    const struct btrfs_trans_handle *trans,
				    const struct btrfs_path *path,
				    const u64 hole_offset,
				    const u64 hole_len)
{
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
	struct extent_map *em;
	int ret;

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

3321 3322 3323 3324 3325
	if (path) {
		struct btrfs_file_extent_item *fi;

		fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
				    struct btrfs_file_extent_item);
3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355
		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);
	}

3356
	if (ret)
3357 3358 3359 3360
		set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
			&BTRFS_I(inode)->runtime_flags);
}

3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504
/*
 * Make sure we do not end up inserting an inline extent into a file that has
 * already other (non-inline) extents. If a file has an inline extent it can
 * not have any other extents and the (single) inline extent must start at the
 * file offset 0. Failing to respect these rules will lead to file corruption,
 * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc
 *
 * We can have extents that have been already written to disk or we can have
 * dirty ranges still in delalloc, in which case the extent maps and items are
 * created only when we run delalloc, and the delalloc ranges might fall outside
 * the range we are currently locking in the inode's io tree. So we check the
 * inode's i_size because of that (i_size updates are done while holding the
 * i_mutex, which we are holding here).
 * We also check to see if the inode has a size not greater than "datal" but has
 * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are
 * protected against such concurrent fallocate calls by the i_mutex).
 *
 * If the file has no extents but a size greater than datal, do not allow the
 * copy because we would need turn the inline extent into a non-inline one (even
 * with NO_HOLES enabled). If we find our destination inode only has one inline
 * extent, just overwrite it with the source inline extent if its size is less
 * than the source extent's size, or we could copy the source inline extent's
 * data into the destination inode's inline extent if the later is greater then
 * the former.
 */
static int clone_copy_inline_extent(struct inode *src,
				    struct inode *dst,
				    struct btrfs_trans_handle *trans,
				    struct btrfs_path *path,
				    struct btrfs_key *new_key,
				    const u64 drop_start,
				    const u64 datal,
				    const u64 skip,
				    const u64 size,
				    char *inline_data)
{
	struct btrfs_root *root = BTRFS_I(dst)->root;
	const u64 aligned_end = ALIGN(new_key->offset + datal,
				      root->sectorsize);
	int ret;
	struct btrfs_key key;

	if (new_key->offset > 0)
		return -EOPNOTSUPP;

	key.objectid = btrfs_ino(dst);
	key.type = BTRFS_EXTENT_DATA_KEY;
	key.offset = 0;
	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
	if (ret < 0) {
		return ret;
	} else if (ret > 0) {
		if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
			ret = btrfs_next_leaf(root, path);
			if (ret < 0)
				return ret;
			else if (ret > 0)
				goto copy_inline_extent;
		}
		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
		if (key.objectid == btrfs_ino(dst) &&
		    key.type == BTRFS_EXTENT_DATA_KEY) {
			ASSERT(key.offset > 0);
			return -EOPNOTSUPP;
		}
	} else if (i_size_read(dst) <= datal) {
		struct btrfs_file_extent_item *ei;
		u64 ext_len;

		/*
		 * If the file size is <= datal, make sure there are no other
		 * extents following (can happen do to an fallocate call with
		 * the flag FALLOC_FL_KEEP_SIZE).
		 */
		ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
				    struct btrfs_file_extent_item);
		/*
		 * If it's an inline extent, it can not have other extents
		 * following it.
		 */
		if (btrfs_file_extent_type(path->nodes[0], ei) ==
		    BTRFS_FILE_EXTENT_INLINE)
			goto copy_inline_extent;

		ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
		if (ext_len > aligned_end)
			return -EOPNOTSUPP;

		ret = btrfs_next_item(root, path);
		if (ret < 0) {
			return ret;
		} else if (ret == 0) {
			btrfs_item_key_to_cpu(path->nodes[0], &key,
					      path->slots[0]);
			if (key.objectid == btrfs_ino(dst) &&
			    key.type == BTRFS_EXTENT_DATA_KEY)
				return -EOPNOTSUPP;
		}
	}

copy_inline_extent:
	/*
	 * We have no extent items, or we have an extent at offset 0 which may
	 * or may not be inlined. All these cases are dealt the same way.
	 */
	if (i_size_read(dst) > datal) {
		/*
		 * If the destination inode has an inline extent...
		 * This would require copying the data from the source inline
		 * extent into the beginning of the destination's inline extent.
		 * But this is really complex, both extents can be compressed
		 * or just one of them, which would require decompressing and
		 * re-compressing data (which could increase the new compressed
		 * size, not allowing the compressed data to fit anymore in an
		 * inline extent).
		 * So just don't support this case for now (it should be rare,
		 * we are not really saving space when cloning inline extents).
		 */
		return -EOPNOTSUPP;
	}

	btrfs_release_path(path);
	ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1);
	if (ret)
		return ret;
	ret = btrfs_insert_empty_item(trans, root, path, new_key, size);
	if (ret)
		return ret;

	if (skip) {
		const u32 start = btrfs_file_extent_calc_inline_size(0);

		memmove(inline_data + start, inline_data + start + skip, datal);
	}

	write_extent_buffer(path->nodes[0], inline_data,
			    btrfs_item_ptr_offset(path->nodes[0],
						  path->slots[0]),
			    size);
	inode_add_bytes(dst, datal);

	return 0;
}

3505 3506 3507 3508 3509 3510 3511
/**
 * 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
3512
 * @olen_aligned: Block-aligned value of olen
3513
 * @destoff: Offset within @inode to start clone
3514
 * @no_time_update: Whether to update mtime/ctime on the target inode
3515 3516
 */
static int btrfs_clone(struct inode *src, struct inode *inode,
3517
		       const u64 off, const u64 olen, const u64 olen_aligned,
3518
		       const u64 destoff, int no_time_update)
C
Christoph Hellwig 已提交
3519 3520
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
3521
	struct btrfs_path *path = NULL;
C
Christoph Hellwig 已提交
3522
	struct extent_buffer *leaf;
3523 3524
	struct btrfs_trans_handle *trans;
	char *buf = NULL;
Y
Yan Zheng 已提交
3525
	struct btrfs_key key;
C
Christoph Hellwig 已提交
3526 3527
	u32 nritems;
	int slot;
Y
Yan Zheng 已提交
3528
	int ret;
3529 3530
	const u64 len = olen_aligned;
	u64 last_dest_end = destoff;
Y
Yan Zheng 已提交
3531 3532

	ret = -ENOMEM;
3533 3534 3535 3536 3537 3538
	buf = kmalloc(root->nodesize, GFP_KERNEL | __GFP_NOWARN);
	if (!buf) {
		buf = vmalloc(root->nodesize);
		if (!buf)
			return ret;
	}
Y
Yan Zheng 已提交
3539 3540 3541

	path = btrfs_alloc_path();
	if (!path) {
3542
		kvfree(buf);
3543
		return ret;
3544 3545
	}

3546
	path->reada = READA_FORWARD;
3547
	/* clone data */
L
Li Zefan 已提交
3548
	key.objectid = btrfs_ino(src);
Y
Yan Zheng 已提交
3549
	key.type = BTRFS_EXTENT_DATA_KEY;
3550
	key.offset = off;
C
Christoph Hellwig 已提交
3551 3552

	while (1) {
3553
		u64 next_key_min_offset = key.offset + 1;
3554

C
Christoph Hellwig 已提交
3555 3556 3557 3558
		/*
		 * note the key will change type as we walk through the
		 * tree.
		 */
3559
		path->leave_spinning = 1;
3560 3561
		ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
				0, 0);
C
Christoph Hellwig 已提交
3562 3563
		if (ret < 0)
			goto out;
3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574
		/*
		 * 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
3575

Y
Yan Zheng 已提交
3576
		nritems = btrfs_header_nritems(path->nodes[0]);
3577
process_slot:
Y
Yan Zheng 已提交
3578
		if (path->slots[0] >= nritems) {
3579
			ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
C
Christoph Hellwig 已提交
3580 3581 3582 3583
			if (ret < 0)
				goto out;
			if (ret > 0)
				break;
Y
Yan Zheng 已提交
3584
			nritems = btrfs_header_nritems(path->nodes[0]);
C
Christoph Hellwig 已提交
3585 3586 3587 3588
		}
		leaf = path->nodes[0];
		slot = path->slots[0];

Y
Yan Zheng 已提交
3589
		btrfs_item_key_to_cpu(leaf, &key, slot);
3590
		if (key.type > BTRFS_EXTENT_DATA_KEY ||
L
Li Zefan 已提交
3591
		    key.objectid != btrfs_ino(src))
C
Christoph Hellwig 已提交
3592 3593
			break;

3594
		if (key.type == BTRFS_EXTENT_DATA_KEY) {
3595 3596
			struct btrfs_file_extent_item *extent;
			int type;
Z
Zheng Yan 已提交
3597 3598
			u32 size;
			struct btrfs_key new_key;
3599 3600 3601
			u64 disko = 0, diskl = 0;
			u64 datao = 0, datal = 0;
			u8 comp;
3602
			u64 drop_start;
Z
Zheng Yan 已提交
3603

3604 3605 3606 3607
			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);
3608 3609
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
C
Chris Mason 已提交
3610 3611 3612 3613
				disko = btrfs_file_extent_disk_bytenr(leaf,
								      extent);
				diskl = btrfs_file_extent_disk_num_bytes(leaf,
								 extent);
3614
				datao = btrfs_file_extent_offset(leaf, extent);
C
Chris Mason 已提交
3615 3616
				datal = btrfs_file_extent_num_bytes(leaf,
								    extent);
3617 3618 3619 3620 3621
			} 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
3622

3623 3624 3625 3626 3627 3628
			/*
			 * 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) {
3629 3630
				path->slots[0]++;
				goto process_slot;
3631 3632
			} else if (key.offset >= off + len) {
				break;
3633
			}
3634
			next_key_min_offset = key.offset + datal;
3635 3636 3637 3638 3639 3640 3641
			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;
3642

Z
Zheng Yan 已提交
3643
			memcpy(&new_key, &key, sizeof(new_key));
L
Li Zefan 已提交
3644
			new_key.objectid = btrfs_ino(inode);
3645 3646 3647 3648
			if (off <= key.offset)
				new_key.offset = key.offset + destoff - off;
			else
				new_key.offset = destoff;
Z
Zheng Yan 已提交
3649

3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661
			/*
			 * 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;

3662 3663 3664 3665 3666 3667
			/*
			 * 1 - adjusting old extent (we may have to split it)
			 * 1 - add new extent
			 * 1 - inode update
			 */
			trans = btrfs_start_transaction(root, 3);
3668 3669 3670 3671 3672
			if (IS_ERR(trans)) {
				ret = PTR_ERR(trans);
				goto out;
			}

3673 3674
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
3675 3676 3677 3678 3679
				/*
				 *    a  | --- range to clone ---|  b
				 * | ------------- extent ------------- |
				 */

3680
				/* subtract range b */
3681 3682 3683
				if (key.offset + datal > off + len)
					datal = off + len - key.offset;

3684
				/* subtract range a */
3685 3686 3687 3688 3689
				if (off > key.offset) {
					datao += off - key.offset;
					datal -= off - key.offset;
				}

J
Josef Bacik 已提交
3690
				ret = btrfs_drop_extents(trans, root, inode,
3691
							 drop_start,
3692
							 new_key.offset + datal,
3693
							 1);
3694
				if (ret) {
3695
					if (ret != -EOPNOTSUPP)
3696 3697
						btrfs_abort_transaction(trans,
								root, ret);
3698 3699 3700
					btrfs_end_transaction(trans, root);
					goto out;
				}
3701

3702 3703
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
3704 3705 3706 3707 3708 3709
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
3710 3711 3712 3713

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
Z
Zheng Yan 已提交
3714 3715
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
Y
Yan Zheng 已提交
3716

3717
				extent = btrfs_item_ptr(leaf, slot,
C
Christoph Hellwig 已提交
3718
						struct btrfs_file_extent_item);
3719 3720 3721 3722 3723 3724 3725 3726 3727

				/* 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
3728

3729 3730
				if (disko) {
					inode_add_bytes(inode, datal);
Y
Yan Zheng 已提交
3731
					ret = btrfs_inc_extent_ref(trans, root,
3732 3733
							disko, diskl, 0,
							root->root_key.objectid,
L
Li Zefan 已提交
3734
							btrfs_ino(inode),
3735
							new_key.offset - datao);
3736 3737 3738 3739 3740 3741 3742 3743 3744
					if (ret) {
						btrfs_abort_transaction(trans,
									root,
									ret);
						btrfs_end_transaction(trans,
								      root);
						goto out;

					}
C
Christoph Hellwig 已提交
3745
				}
3746 3747 3748
			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
				u64 skip = 0;
				u64 trim = 0;
3749

3750 3751 3752 3753
				if (off > key.offset) {
					skip = off - key.offset;
					new_key.offset += skip;
				}
C
Chris Mason 已提交
3754

L
Liu Bo 已提交
3755 3756
				if (key.offset + datal > off + len)
					trim = key.offset + datal - (off + len);
C
Chris Mason 已提交
3757

3758 3759
				if (comp && (skip || trim)) {
					ret = -EINVAL;
3760
					btrfs_end_transaction(trans, root);
3761 3762 3763 3764
					goto out;
				}
				size -= skip + trim;
				datal -= skip + trim;
3765

3766 3767 3768 3769 3770 3771
				ret = clone_copy_inline_extent(src, inode,
							       trans, path,
							       &new_key,
							       drop_start,
							       datal,
							       skip, size, buf);
3772
				if (ret) {
3773
					if (ret != -EOPNOTSUPP)
3774
						btrfs_abort_transaction(trans,
3775 3776
									root,
									ret);
3777 3778 3779
					btrfs_end_transaction(trans, root);
					goto out;
				}
3780 3781
				leaf = path->nodes[0];
				slot = path->slots[0];
C
Christoph Hellwig 已提交
3782
			}
3783

3784 3785 3786
			/* If we have an implicit hole (NO_HOLES feature). */
			if (drop_start < new_key.offset)
				clone_update_extent_map(inode, trans,
3787
						NULL, drop_start,
3788 3789
						new_key.offset - drop_start);

3790
			clone_update_extent_map(inode, trans, path, 0, 0);
3791

3792
			btrfs_mark_buffer_dirty(leaf);
3793
			btrfs_release_path(path);
3794

3795 3796
			last_dest_end = ALIGN(new_key.offset + datal,
					      root->sectorsize);
3797 3798
			ret = clone_finish_inode_update(trans, inode,
							last_dest_end,
3799 3800
							destoff, olen,
							no_time_update);
3801
			if (ret)
3802
				goto out;
3803 3804
			if (new_key.offset + datal >= destoff + len)
				break;
3805
		}
3806
		btrfs_release_path(path);
3807
		key.offset = next_key_min_offset;
C
Christoph Hellwig 已提交
3808 3809
	}
	ret = 0;
3810

3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834
	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;
		}
3835 3836
		clone_update_extent_map(inode, trans, NULL, last_dest_end,
					destoff + len - last_dest_end);
3837
		ret = clone_finish_inode_update(trans, inode, destoff + len,
3838
						destoff, olen, no_time_update);
3839 3840
	}

C
Christoph Hellwig 已提交
3841
out:
3842
	btrfs_free_path(path);
3843
	kvfree(buf);
3844 3845 3846
	return ret;
}

3847 3848
static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
					u64 off, u64 olen, u64 destoff)
3849
{
A
Al Viro 已提交
3850
	struct inode *inode = file_inode(file);
3851
	struct inode *src = file_inode(file_src);
3852 3853 3854 3855
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret;
	u64 len = olen;
	u64 bs = root->fs_info->sb->s_blocksize;
3856
	int same_inode = src == inode;
3857 3858 3859 3860 3861 3862 3863

	/*
	 * 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.
3864 3865 3866
	 *
	 * - split destination inode's inline extents.  The inline extents can
	 *   be either compressed or non-compressed.
3867 3868 3869 3870 3871
	 */

	if (btrfs_root_readonly(root))
		return -EROFS;

3872 3873 3874
	if (file_src->f_path.mnt != file->f_path.mnt ||
	    src->i_sb != inode->i_sb)
		return -EXDEV;
3875 3876 3877 3878

	/* don't make the dst file partly checksummed */
	if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
	    (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3879
		return -EINVAL;
3880 3881

	if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3882
		return -EISDIR;
3883 3884

	if (!same_inode) {
3885
		btrfs_double_inode_lock(src, inode);
3886
	} else {
A
Al Viro 已提交
3887
		inode_lock(src);
3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899
	}

	/* 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;

3900 3901 3902 3903 3904
	if (len == 0) {
		ret = 0;
		goto out_unlock;
	}

3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921
	/* 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;
	}

3922 3923 3924 3925 3926 3927 3928 3929 3930 3931
	/*
	 * 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;
3932

3933
		ret = lock_extent_range(src, lock_start, lock_len, true);
3934
	} else {
3935 3936 3937 3938 3939 3940 3941
		ret = btrfs_double_extent_lock(src, off, inode, destoff, len,
					       true);
	}
	ASSERT(ret == 0);
	if (WARN_ON(ret)) {
		/* ranges in the io trees already unlocked */
		goto out_unlock;
3942
	}
3943

3944
	ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
3945

3946 3947 3948 3949 3950 3951
	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 {
3952
		btrfs_double_extent_unlock(src, off, inode, destoff, len);
3953 3954 3955 3956 3957
	}
	/*
	 * Truncate page cache pages so that future reads will see the cloned
	 * data immediately and not the previous data.
	 */
3958
	truncate_inode_pages_range(&inode->i_data,
3959 3960
				round_down(destoff, PAGE_SIZE),
				round_up(destoff + len, PAGE_SIZE) - 1);
C
Christoph Hellwig 已提交
3961
out_unlock:
3962 3963 3964
	if (!same_inode)
		btrfs_double_inode_unlock(src, inode);
	else
A
Al Viro 已提交
3965
		inode_unlock(src);
3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980
	return ret;
}

ssize_t btrfs_copy_file_range(struct file *file_in, loff_t pos_in,
			      struct file *file_out, loff_t pos_out,
			      size_t len, unsigned int flags)
{
	ssize_t ret;

	ret = btrfs_clone_files(file_out, file_in, pos_in, len, pos_out);
	if (ret == 0)
		ret = len;
	return ret;
}

3981 3982
int btrfs_clone_file_range(struct file *src_file, loff_t off,
		struct file *dst_file, loff_t destoff, u64 len)
3983
{
3984
	return btrfs_clone_files(dst_file, src_file, off, len, destoff);
3985 3986
}

C
Christoph Hellwig 已提交
3987 3988 3989 3990 3991 3992
/*
 * 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.
 */
3993
static long btrfs_ioctl_trans_start(struct file *file)
C
Christoph Hellwig 已提交
3994
{
A
Al Viro 已提交
3995
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
3996 3997
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
3998
	int ret;
C
Christoph Hellwig 已提交
3999

4000
	ret = -EPERM;
4001
	if (!capable(CAP_SYS_ADMIN))
4002
		goto out;
4003

4004 4005
	ret = -EINPROGRESS;
	if (file->private_data)
C
Christoph Hellwig 已提交
4006
		goto out;
4007

L
Li Zefan 已提交
4008 4009 4010 4011
	ret = -EROFS;
	if (btrfs_root_readonly(root))
		goto out;

4012
	ret = mnt_want_write_file(file);
Y
Yan Zheng 已提交
4013 4014 4015
	if (ret)
		goto out;

J
Josef Bacik 已提交
4016
	atomic_inc(&root->fs_info->open_ioctl_trans);
4017

4018
	ret = -ENOMEM;
4019
	trans = btrfs_start_ioctl_transaction(root);
4020
	if (IS_ERR(trans))
4021 4022 4023 4024 4025 4026
		goto out_drop;

	file->private_data = trans;
	return 0;

out_drop:
J
Josef Bacik 已提交
4027
	atomic_dec(&root->fs_info->open_ioctl_trans);
A
Al Viro 已提交
4028
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
4029 4030 4031 4032
out:
	return ret;
}

4033 4034
static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
{
A
Al Viro 已提交
4035
	struct inode *inode = file_inode(file);
4036 4037 4038 4039 4040 4041 4042 4043 4044
	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;
4045
	int ret;
4046 4047 4048 4049

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

4050 4051 4052 4053 4054 4055 4056 4057
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	if (copy_from_user(&objectid, argp, sizeof(objectid))) {
		ret = -EFAULT;
		goto out;
	}
4058 4059

	if (!objectid)
4060
		objectid = BTRFS_FS_TREE_OBJECTID;
4061 4062 4063 4064 4065 4066

	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);
4067 4068 4069 4070
	if (IS_ERR(new_root)) {
		ret = PTR_ERR(new_root);
		goto out;
	}
4071 4072

	path = btrfs_alloc_path();
4073 4074 4075 4076
	if (!path) {
		ret = -ENOMEM;
		goto out;
	}
4077 4078 4079
	path->leave_spinning = 1;

	trans = btrfs_start_transaction(root, 1);
4080
	if (IS_ERR(trans)) {
4081
		btrfs_free_path(path);
4082 4083
		ret = PTR_ERR(trans);
		goto out;
4084 4085
	}

4086
	dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
4087 4088
	di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
				   dir_id, "default", 7, 1);
4089
	if (IS_ERR_OR_NULL(di)) {
4090 4091
		btrfs_free_path(path);
		btrfs_end_transaction(trans, root);
4092 4093
		btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
			   "item, this isn't going to work");
4094 4095
		ret = -ENOENT;
		goto out;
4096 4097 4098 4099 4100 4101 4102
	}

	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);

4103
	btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
4104
	btrfs_end_transaction(trans, root);
4105 4106 4107
out:
	mnt_drop_write_file(file);
	return ret;
4108 4109
}

4110 4111
void btrfs_get_block_group_info(struct list_head *groups_list,
				struct btrfs_ioctl_space_info *space)
4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125
{
	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);
	}
}

4126
static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
J
Josef Bacik 已提交
4127 4128 4129 4130
{
	struct btrfs_ioctl_space_args space_args;
	struct btrfs_ioctl_space_info space;
	struct btrfs_ioctl_space_info *dest;
4131
	struct btrfs_ioctl_space_info *dest_orig;
4132
	struct btrfs_ioctl_space_info __user *user_dest;
J
Josef Bacik 已提交
4133
	struct btrfs_space_info *info;
4134 4135 4136 4137 4138
	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;
4139
	int alloc_size;
J
Josef Bacik 已提交
4140
	int ret = 0;
4141
	u64 slot_count = 0;
4142
	int i, c;
J
Josef Bacik 已提交
4143 4144 4145 4146 4147 4148

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

4149 4150 4151 4152 4153 4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171 4172
	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);
	}
4173

4174 4175 4176 4177 4178
	/*
	 * Global block reserve, exported as a space_info
	 */
	slot_count++;

4179 4180 4181 4182 4183
	/* space_slots == 0 means they are asking for a count */
	if (space_args.space_slots == 0) {
		space_args.total_spaces = slot_count;
		goto out;
	}
4184

4185
	slot_count = min_t(u64, space_args.space_slots, slot_count);
4186

4187
	alloc_size = sizeof(*dest) * slot_count;
4188

4189 4190 4191
	/* 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
	 */
4192
	if (alloc_size > PAGE_SIZE)
4193 4194
		return -ENOMEM;

J
Josef Bacik 已提交
4195
	space_args.total_spaces = 0;
4196
	dest = kmalloc(alloc_size, GFP_KERNEL);
4197 4198 4199
	if (!dest)
		return -ENOMEM;
	dest_orig = dest;
J
Josef Bacik 已提交
4200

4201
	/* now we have a buffer to copy into */
4202 4203 4204
	for (i = 0; i < num_types; i++) {
		struct btrfs_space_info *tmp;

4205 4206 4207
		if (!slot_count)
			break;

4208 4209 4210 4211 4212 4213 4214 4215 4216 4217
		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();
4218

4219 4220 4221 4222 4223
		if (!info)
			continue;
		down_read(&info->groups_sem);
		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
			if (!list_empty(&info->block_groups[c])) {
4224 4225
				btrfs_get_block_group_info(
					&info->block_groups[c], &space);
4226 4227 4228
				memcpy(dest, &space, sizeof(space));
				dest++;
				space_args.total_spaces++;
4229
				slot_count--;
4230
			}
4231 4232
			if (!slot_count)
				break;
4233 4234
		}
		up_read(&info->groups_sem);
J
Josef Bacik 已提交
4235 4236
	}

4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249 4250 4251
	/*
	 * 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
4252
	user_dest = (struct btrfs_ioctl_space_info __user *)
4253 4254 4255 4256 4257 4258 4259 4260
		(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
4261 4262 4263 4264 4265
		ret = -EFAULT;

	return ret;
}

C
Christoph Hellwig 已提交
4266 4267 4268 4269 4270 4271 4272 4273
/*
 * 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
4274
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
4275 4276 4277 4278
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;

	trans = file->private_data;
4279 4280
	if (!trans)
		return -EINVAL;
C
Christoph Hellwig 已提交
4281
	file->private_data = NULL;
4282

4283 4284
	btrfs_end_transaction(trans, root);

J
Josef Bacik 已提交
4285
	atomic_dec(&root->fs_info->open_ioctl_trans);
4286

A
Al Viro 已提交
4287
	mnt_drop_write_file(file);
4288
	return 0;
C
Christoph Hellwig 已提交
4289 4290
}

4291 4292
static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
					    void __user *argp)
4293 4294 4295
{
	struct btrfs_trans_handle *trans;
	u64 transid;
T
Tsutomu Itoh 已提交
4296
	int ret;
4297

M
Miao Xie 已提交
4298
	trans = btrfs_attach_transaction_barrier(root);
4299 4300 4301 4302 4303 4304 4305 4306
	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;
	}
4307
	transid = trans->transid;
T
Tsutomu Itoh 已提交
4308
	ret = btrfs_commit_transaction_async(trans, root, 0);
4309 4310
	if (ret) {
		btrfs_end_transaction(trans, root);
T
Tsutomu Itoh 已提交
4311
		return ret;
4312
	}
4313
out:
4314 4315 4316 4317 4318 4319
	if (argp)
		if (copy_to_user(argp, &transid, sizeof(transid)))
			return -EFAULT;
	return 0;
}

4320 4321
static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
					   void __user *argp)
4322 4323 4324 4325 4326 4327 4328 4329 4330 4331 4332 4333
{
	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
4334
static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
J
Jan Schmidt 已提交
4335
{
A
Al Viro 已提交
4336
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4337
	struct btrfs_ioctl_scrub_args *sa;
M
Miao Xie 已提交
4338
	int ret;
J
Jan Schmidt 已提交
4339 4340 4341 4342 4343 4344 4345 4346

	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
4347 4348 4349 4350 4351 4352
	if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
		ret = mnt_want_write_file(file);
		if (ret)
			goto out;
	}

4353
	ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4354 4355
			      &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
			      0);
J
Jan Schmidt 已提交
4356 4357 4358 4359

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

M
Miao Xie 已提交
4360 4361 4362
	if (!(sa->flags & BTRFS_SCRUB_READONLY))
		mnt_drop_write_file(file);
out:
J
Jan Schmidt 已提交
4363 4364 4365 4366 4367 4368 4369 4370 4371
	kfree(sa);
	return ret;
}

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

4372
	return btrfs_scrub_cancel(root->fs_info);
J
Jan Schmidt 已提交
4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396
}

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;
}

4397
static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4398
				      void __user *arg)
4399 4400 4401 4402 4403 4404 4405 4406
{
	struct btrfs_ioctl_get_dev_stats *sa;
	int ret;

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

4407 4408 4409 4410 4411 4412
	if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
		kfree(sa);
		return -EPERM;
	}

	ret = btrfs_get_dev_stats(root, sa);
4413 4414 4415 4416 4417 4418 4419 4420

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

	kfree(sa);
	return ret;
}

4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434
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:
4435 4436 4437 4438
		if (root->fs_info->sb->s_flags & MS_RDONLY) {
			ret = -EROFS;
			goto out;
		}
4439 4440 4441
		if (atomic_xchg(
			&root->fs_info->mutually_exclusive_operation_running,
			1)) {
4442
			ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4443
		} else {
4444
			ret = btrfs_dev_replace_by_ioctl(root, p);
4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462 4463
			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;
4464
out:
4465 4466 4467 4468
	kfree(p);
	return ret;
}

4469 4470 4471 4472
static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
{
	int ret = 0;
	int i;
4473
	u64 rel_ptr;
4474
	int size;
4475
	struct btrfs_ioctl_ino_path_args *ipa = NULL;
4476 4477 4478
	struct inode_fs_paths *ipath = NULL;
	struct btrfs_path *path;

4479
	if (!capable(CAP_DAC_READ_SEARCH))
4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507
		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) {
4508 4509
		rel_ptr = ipath->fspath->val[i] -
			  (u64)(unsigned long)ipath->fspath->val;
4510
		ipath->fspath->val[i] = rel_ptr;
4511 4512
	}

4513 4514
	ret = copy_to_user((void *)(unsigned long)ipa->fspath,
			   (void *)(unsigned long)ipath->fspath, size);
4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572
	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;
	}

4573
	size = min_t(u32, loi->size, SZ_64K);
4574 4575 4576 4577 4578 4579 4580
	inodes = init_data_container(size);
	if (IS_ERR(inodes)) {
		ret = PTR_ERR(inodes);
		inodes = NULL;
		goto out;
	}

L
Liu Bo 已提交
4581 4582 4583
	ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
					  build_ino_list, inodes);
	if (ret == -EINVAL)
4584 4585 4586 4587
		ret = -ENOENT;
	if (ret < 0)
		goto out;

4588 4589
	ret = copy_to_user((void *)(unsigned long)loi->inodes,
			   (void *)(unsigned long)inodes, size);
4590 4591 4592 4593 4594
	if (ret)
		ret = -EFAULT;

out:
	btrfs_free_path(path);
4595
	vfree(inodes);
4596 4597 4598 4599 4600
	kfree(loi);

	return ret;
}

4601
void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4602 4603 4604 4605 4606 4607
			       struct btrfs_ioctl_balance_args *bargs)
{
	struct btrfs_balance_control *bctl = fs_info->balance_ctl;

	bargs->flags = bctl->flags;

4608 4609 4610 4611
	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;
4612 4613
	if (atomic_read(&fs_info->balance_cancel_req))
		bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4614

4615 4616 4617
	memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
	memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
	memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4618 4619 4620 4621 4622 4623 4624 4625

	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));
	}
4626 4627
}

4628
static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4629
{
A
Al Viro 已提交
4630
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4631 4632 4633
	struct btrfs_fs_info *fs_info = root->fs_info;
	struct btrfs_ioctl_balance_args *bargs;
	struct btrfs_balance_control *bctl;
4634
	bool need_unlock; /* for mut. excl. ops lock */
4635 4636 4637 4638 4639
	int ret;

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

4640
	ret = mnt_want_write_file(file);
4641 4642 4643
	if (ret)
		return ret;

4644 4645 4646 4647 4648 4649 4650 4651 4652
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;
	}

	/*
4653
	 * mut. excl. ops lock is locked.  Three possibilities:
4654 4655 4656 4657
	 *   (1) some other op is running
	 *   (2) balance is running
	 *   (3) balance is paused -- special case (think resume)
	 */
4658
	mutex_lock(&fs_info->balance_mutex);
4659 4660 4661 4662 4663 4664 4665 4666 4667 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678 4679 4680 4681 4682 4683 4684 4685
	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);
4686
		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4687 4688 4689 4690 4691
		goto out;
	}

locked:
	BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4692 4693 4694 4695 4696

	if (arg) {
		bargs = memdup_user(arg, sizeof(*bargs));
		if (IS_ERR(bargs)) {
			ret = PTR_ERR(bargs);
4697
			goto out_unlock;
4698
		}
4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710 4711 4712

		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;
		}
4713 4714 4715 4716
	} else {
		bargs = NULL;
	}

4717
	if (fs_info->balance_ctl) {
4718 4719 4720 4721
		ret = -EINPROGRESS;
		goto out_bargs;
	}

4722
	bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4723 4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734
	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;
4735 4736 4737
	} else {
		/* balance everything - no filters */
		bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4738 4739
	}

4740 4741
	if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
		ret = -EINVAL;
4742
		goto out_bctl;
4743 4744
	}

4745
do_balance:
4746
	/*
4747 4748 4749 4750 4751
	 * 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.
4752
	 */
4753 4754 4755
	need_unlock = false;

	ret = btrfs_balance(bctl, bargs);
4756
	bctl = NULL;
4757

4758 4759 4760 4761 4762
	if (arg) {
		if (copy_to_user(arg, bargs, sizeof(*bargs)))
			ret = -EFAULT;
	}

4763 4764
out_bctl:
	kfree(bctl);
4765 4766
out_bargs:
	kfree(bargs);
4767
out_unlock:
4768 4769
	mutex_unlock(&fs_info->balance_mutex);
	mutex_unlock(&fs_info->volume_mutex);
4770 4771 4772
	if (need_unlock)
		atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
out:
4773
	mnt_drop_write_file(file);
4774 4775 4776
	return ret;
}

4777 4778 4779 4780 4781 4782 4783 4784
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);
4785 4786
	case BTRFS_BALANCE_CTL_CANCEL:
		return btrfs_cancel_balance(root->fs_info);
4787 4788 4789 4790 4791
	}

	return -EINVAL;
}

4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807
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;
	}

4808
	bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820 4821 4822 4823 4824
	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;
}

4825
static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4826
{
A
Al Viro 已提交
4827
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4828 4829 4830 4831 4832 4833 4834 4835
	struct btrfs_ioctl_quota_ctl_args *sa;
	struct btrfs_trans_handle *trans = NULL;
	int ret;
	int err;

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

4836 4837 4838
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4839 4840

	sa = memdup_user(arg, sizeof(*sa));
4841 4842 4843 4844
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4845

4846
	down_write(&root->fs_info->subvol_sem);
J
Jan Schmidt 已提交
4847 4848 4849 4850
	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
4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861 4862 4863 4864
	}

	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
4865 4866 4867
	err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
	if (err && !ret)
		ret = err;
A
Arne Jansen 已提交
4868 4869
out:
	kfree(sa);
4870
	up_write(&root->fs_info->subvol_sem);
4871 4872
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4873 4874 4875
	return ret;
}

4876
static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4877
{
A
Al Viro 已提交
4878
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4879 4880 4881 4882 4883 4884 4885 4886
	struct btrfs_ioctl_qgroup_assign_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;

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

4887 4888 4889
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4890 4891

	sa = memdup_user(arg, sizeof(*sa));
4892 4893 4894 4895
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911

	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);
	}

4912 4913 4914
	/* update qgroup status and info */
	err = btrfs_run_qgroups(trans, root->fs_info);
	if (err < 0)
4915 4916
		btrfs_handle_fs_error(root->fs_info, err,
			    "failed to update qgroup status and info");
A
Arne Jansen 已提交
4917 4918 4919 4920 4921 4922
	err = btrfs_end_transaction(trans, root);
	if (err && !ret)
		ret = err;

out:
	kfree(sa);
4923 4924
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4925 4926 4927
	return ret;
}

4928
static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4929
{
A
Al Viro 已提交
4930
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4931 4932 4933 4934 4935 4936 4937 4938
	struct btrfs_ioctl_qgroup_create_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;

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

4939 4940 4941
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4942 4943

	sa = memdup_user(arg, sizeof(*sa));
4944 4945 4946 4947
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4948

M
Miao Xie 已提交
4949 4950 4951 4952 4953
	if (!sa->qgroupid) {
		ret = -EINVAL;
		goto out;
	}

A
Arne Jansen 已提交
4954 4955 4956 4957 4958 4959 4960 4961
	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) {
4962
		ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid);
A
Arne Jansen 已提交
4963 4964 4965 4966 4967 4968 4969 4970 4971 4972
	} 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);
4973 4974
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4975 4976 4977
	return ret;
}

4978
static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4979
{
A
Al Viro 已提交
4980
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4981 4982 4983 4984 4985 4986 4987 4988 4989
	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;

4990 4991 4992
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4993 4994

	sa = memdup_user(arg, sizeof(*sa));
4995 4996 4997 4998
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020

	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);
5021 5022
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
5023 5024 5025
	return ret;
}

J
Jan Schmidt 已提交
5026 5027
static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
{
A
Al Viro 已提交
5028
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060
	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
5061
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
5062 5063 5064 5065 5066 5067
	struct btrfs_ioctl_quota_rescan_args *qsa;
	int ret = 0;

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

5068
	qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
J
Jan Schmidt 已提交
5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083
	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;
}

5084 5085
static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
{
A
Al Viro 已提交
5086
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5087 5088 5089 5090 5091 5092 5093

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

	return btrfs_qgroup_wait_for_completion(root->fs_info);
}

5094 5095
static long _btrfs_ioctl_set_received_subvol(struct file *file,
					    struct btrfs_ioctl_received_subvol_args *sa)
5096
{
A
Al Viro 已提交
5097
	struct inode *inode = file_inode(file);
5098 5099 5100
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_root_item *root_item = &root->root_item;
	struct btrfs_trans_handle *trans;
5101
	struct timespec ct = current_fs_time(inode->i_sb);
5102
	int ret = 0;
5103
	int received_uuid_changed;
5104

5105 5106 5107
	if (!inode_owner_or_capable(inode))
		return -EPERM;

5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123
	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;
	}

5124 5125 5126 5127 5128
	/*
	 * 1 - root item
	 * 2 - uuid items (received uuid + subvol uuid)
	 */
	trans = btrfs_start_transaction(root, 3);
5129 5130 5131 5132 5133 5134 5135 5136 5137 5138
	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;

5139 5140 5141 5142 5143 5144 5145 5146
	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);
5147 5148 5149
	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);
5150 5151 5152 5153
	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);
5154 5155 5156 5157 5158 5159

	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;
5160 5161 5162 5163 5164 5165 5166 5167
	}
	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);
5168
			goto out;
5169 5170 5171 5172 5173 5174
		}
	}
	ret = btrfs_commit_transaction(trans, root);
	if (ret < 0) {
		btrfs_abort_transaction(trans, root, ret);
		goto out;
5175 5176
	}

5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197
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;
	}

5198
	args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
5199 5200
	if (!args64) {
		ret = -ENOMEM;
5201 5202 5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254
		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;

5255 5256 5257 5258 5259 5260 5261 5262 5263
	ret = copy_to_user(arg, sa, sizeof(*sa));
	if (ret)
		ret = -EFAULT;

out:
	kfree(sa);
	return ret;
}

5264 5265
static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
{
A
Al Viro 已提交
5266
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5267
	size_t len;
5268
	int ret;
5269 5270 5271 5272 5273 5274 5275
	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);
5276 5277

	if (len == BTRFS_LABEL_SIZE) {
5278 5279
		btrfs_warn(root->fs_info,
			"label is too long, return the first %zu bytes", --len);
5280 5281 5282 5283 5284 5285 5286
	}

	ret = copy_to_user(arg, label, len);

	return ret ? -EFAULT : 0;
}

5287 5288
static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
{
A
Al Viro 已提交
5289
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5290 5291 5292 5293 5294 5295 5296 5297 5298 5299 5300 5301
	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) {
5302
		btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315 5316
		       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;
	}

5317
	spin_lock(&root->fs_info->super_lock);
5318
	strcpy(super_block->label, label);
5319
	spin_unlock(&root->fs_info->super_lock);
5320
	ret = btrfs_commit_transaction(trans, root);
5321 5322 5323 5324 5325 5326

out_unlock:
	mnt_drop_write_file(file);
	return ret;
}

5327 5328 5329 5330 5331
#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 }

5332
int btrfs_ioctl_get_supported_features(void __user *arg)
5333
{
D
David Sterba 已提交
5334
	static const struct btrfs_ioctl_feature_flags features[3] = {
5335 5336 5337 5338 5339 5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360 5361
		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;
}

5362 5363
static int check_feature_bits(struct btrfs_root *root,
			      enum btrfs_feature_set set,
5364 5365 5366
			      u64 change_mask, u64 flags, u64 supported_flags,
			      u64 safe_set, u64 safe_clear)
{
5367 5368
	const char *type = btrfs_feature_set_names[set];
	char *names;
5369 5370 5371 5372 5373 5374
	u64 disallowed, unsupported;
	u64 set_mask = flags & change_mask;
	u64 clear_mask = ~flags & change_mask;

	unsupported = set_mask & ~supported_flags;
	if (unsupported) {
5375 5376 5377 5378 5379 5380 5381 5382
		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,
5383 5384 5385 5386 5387 5388 5389
			   "this kernel does not support %s bits 0x%llx",
			   type, unsupported);
		return -EOPNOTSUPP;
	}

	disallowed = set_mask & ~safe_set;
	if (disallowed) {
5390 5391 5392 5393 5394 5395 5396 5397
		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,
5398 5399 5400 5401 5402 5403 5404
			   "can't set %s bits 0x%llx while mounted",
			   type, disallowed);
		return -EPERM;
	}

	disallowed = clear_mask & ~safe_clear;
	if (disallowed) {
5405 5406 5407 5408 5409 5410 5411 5412
		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,
5413 5414 5415 5416 5417 5418 5419 5420 5421
			   "can't clear %s bits 0x%llx while mounted",
			   type, disallowed);
		return -EPERM;
	}

	return 0;
}

#define check_feature(root, change_mask, flags, mask_base)	\
5422
check_feature_bits(root, FEAT_##mask_base, change_mask, flags,	\
5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440 5441 5442 5443 5444 5445 5446 5447 5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461
		   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;

5462 5463 5464 5465
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

5466
	trans = btrfs_start_transaction(root, 0);
5467 5468 5469 5470
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out_drop_write;
	}
5471 5472 5473 5474 5475 5476 5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488

	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);

5489 5490 5491 5492 5493
	ret = btrfs_commit_transaction(trans, root);
out_drop_write:
	mnt_drop_write_file(file);

	return ret;
5494 5495
}

C
Christoph Hellwig 已提交
5496 5497 5498
long btrfs_ioctl(struct file *file, unsigned int
		cmd, unsigned long arg)
{
A
Al Viro 已提交
5499
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5500
	void __user *argp = (void __user *)arg;
C
Christoph Hellwig 已提交
5501 5502

	switch (cmd) {
5503 5504 5505 5506 5507 5508
	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);
5509 5510
	case FITRIM:
		return btrfs_ioctl_fitrim(file, argp);
C
Christoph Hellwig 已提交
5511
	case BTRFS_IOC_SNAP_CREATE:
5512
		return btrfs_ioctl_snap_create(file, argp, 0);
5513
	case BTRFS_IOC_SNAP_CREATE_V2:
5514
		return btrfs_ioctl_snap_create_v2(file, argp, 0);
5515
	case BTRFS_IOC_SUBVOL_CREATE:
5516
		return btrfs_ioctl_snap_create(file, argp, 1);
A
Arne Jansen 已提交
5517 5518
	case BTRFS_IOC_SUBVOL_CREATE_V2:
		return btrfs_ioctl_snap_create_v2(file, argp, 1);
5519 5520
	case BTRFS_IOC_SNAP_DESTROY:
		return btrfs_ioctl_snap_destroy(file, argp);
5521 5522 5523 5524
	case BTRFS_IOC_SUBVOL_GETFLAGS:
		return btrfs_ioctl_subvol_getflags(file, argp);
	case BTRFS_IOC_SUBVOL_SETFLAGS:
		return btrfs_ioctl_subvol_setflags(file, argp);
5525 5526
	case BTRFS_IOC_DEFAULT_SUBVOL:
		return btrfs_ioctl_default_subvol(file, argp);
C
Christoph Hellwig 已提交
5527
	case BTRFS_IOC_DEFRAG:
C
Chris Mason 已提交
5528 5529 5530
		return btrfs_ioctl_defrag(file, NULL);
	case BTRFS_IOC_DEFRAG_RANGE:
		return btrfs_ioctl_defrag(file, argp);
C
Christoph Hellwig 已提交
5531
	case BTRFS_IOC_RESIZE:
5532
		return btrfs_ioctl_resize(file, argp);
C
Christoph Hellwig 已提交
5533
	case BTRFS_IOC_ADD_DEV:
5534
		return btrfs_ioctl_add_dev(root, argp);
C
Christoph Hellwig 已提交
5535
	case BTRFS_IOC_RM_DEV:
5536
		return btrfs_ioctl_rm_dev(file, argp);
5537 5538
	case BTRFS_IOC_RM_DEV_V2:
		return btrfs_ioctl_rm_dev_v2(file, argp);
J
Jan Schmidt 已提交
5539 5540 5541 5542
	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
5543
	case BTRFS_IOC_BALANCE:
5544
		return btrfs_ioctl_balance(file, NULL);
C
Christoph Hellwig 已提交
5545 5546 5547 5548
	case BTRFS_IOC_TRANS_START:
		return btrfs_ioctl_trans_start(file);
	case BTRFS_IOC_TRANS_END:
		return btrfs_ioctl_trans_end(file);
5549 5550
	case BTRFS_IOC_TREE_SEARCH:
		return btrfs_ioctl_tree_search(file, argp);
G
Gerhard Heift 已提交
5551 5552
	case BTRFS_IOC_TREE_SEARCH_V2:
		return btrfs_ioctl_tree_search_v2(file, argp);
5553 5554
	case BTRFS_IOC_INO_LOOKUP:
		return btrfs_ioctl_ino_lookup(file, argp);
5555 5556 5557 5558
	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
5559 5560
	case BTRFS_IOC_SPACE_INFO:
		return btrfs_ioctl_space_info(root, argp);
5561 5562 5563
	case BTRFS_IOC_SYNC: {
		int ret;

5564
		ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5565 5566
		if (ret)
			return ret;
A
Al Viro 已提交
5567
		ret = btrfs_sync_fs(file_inode(file)->i_sb, 1);
5568 5569
		/*
		 * The transaction thread may want to do more work,
5570
		 * namely it pokes the cleaner kthread that will start
5571 5572 5573
		 * processing uncleaned subvols.
		 */
		wake_up_process(root->fs_info->transaction_kthread);
5574 5575
		return ret;
	}
5576
	case BTRFS_IOC_START_SYNC:
5577
		return btrfs_ioctl_start_sync(root, argp);
5578
	case BTRFS_IOC_WAIT_SYNC:
5579
		return btrfs_ioctl_wait_sync(root, argp);
J
Jan Schmidt 已提交
5580
	case BTRFS_IOC_SCRUB:
M
Miao Xie 已提交
5581
		return btrfs_ioctl_scrub(file, argp);
J
Jan Schmidt 已提交
5582 5583 5584 5585
	case BTRFS_IOC_SCRUB_CANCEL:
		return btrfs_ioctl_scrub_cancel(root, argp);
	case BTRFS_IOC_SCRUB_PROGRESS:
		return btrfs_ioctl_scrub_progress(root, argp);
5586
	case BTRFS_IOC_BALANCE_V2:
5587
		return btrfs_ioctl_balance(file, argp);
5588 5589
	case BTRFS_IOC_BALANCE_CTL:
		return btrfs_ioctl_balance_ctl(root, arg);
5590 5591
	case BTRFS_IOC_BALANCE_PROGRESS:
		return btrfs_ioctl_balance_progress(root, argp);
5592 5593
	case BTRFS_IOC_SET_RECEIVED_SUBVOL:
		return btrfs_ioctl_set_received_subvol(file, argp);
5594 5595 5596 5597
#ifdef CONFIG_64BIT
	case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
		return btrfs_ioctl_set_received_subvol_32(file, argp);
#endif
5598 5599
	case BTRFS_IOC_SEND:
		return btrfs_ioctl_send(file, argp);
5600
	case BTRFS_IOC_GET_DEV_STATS:
5601
		return btrfs_ioctl_get_dev_stats(root, argp);
A
Arne Jansen 已提交
5602
	case BTRFS_IOC_QUOTA_CTL:
5603
		return btrfs_ioctl_quota_ctl(file, argp);
A
Arne Jansen 已提交
5604
	case BTRFS_IOC_QGROUP_ASSIGN:
5605
		return btrfs_ioctl_qgroup_assign(file, argp);
A
Arne Jansen 已提交
5606
	case BTRFS_IOC_QGROUP_CREATE:
5607
		return btrfs_ioctl_qgroup_create(file, argp);
A
Arne Jansen 已提交
5608
	case BTRFS_IOC_QGROUP_LIMIT:
5609
		return btrfs_ioctl_qgroup_limit(file, argp);
J
Jan Schmidt 已提交
5610 5611 5612 5613
	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);
5614 5615
	case BTRFS_IOC_QUOTA_RESCAN_WAIT:
		return btrfs_ioctl_quota_rescan_wait(file, argp);
5616 5617
	case BTRFS_IOC_DEV_REPLACE:
		return btrfs_ioctl_dev_replace(root, argp);
5618 5619
	case BTRFS_IOC_GET_FSLABEL:
		return btrfs_ioctl_get_fslabel(file, argp);
5620 5621
	case BTRFS_IOC_SET_FSLABEL:
		return btrfs_ioctl_set_fslabel(file, argp);
5622
	case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5623
		return btrfs_ioctl_get_supported_features(argp);
5624 5625 5626 5627
	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
5628 5629 5630 5631
	}

	return -ENOTTY;
}
5632 5633 5634 5635 5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652

#ifdef CONFIG_COMPAT
long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	switch (cmd) {
	case FS_IOC32_GETFLAGS:
		cmd = FS_IOC_GETFLAGS;
		break;
	case FS_IOC32_SETFLAGS:
		cmd = FS_IOC_SETFLAGS;
		break;
	case FS_IOC32_GETVERSION:
		cmd = FS_IOC_GETVERSION;
		break;
	default:
		return -ENOIOCTLCMD;
	}

	return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
}
#endif