remarkable-linux/fs/btrfs/raid56.h
Miao Xie 4245215d6a Btrfs, raid56: fix use-after-free problem in the final device replace procedure on raid56
The commit c404e0dc (Btrfs: fix use-after-free in the finishing
procedure of the device replace) fixed a use-after-free problem
which happened when removing the source device at the end of device
replace, but at that time, btrfs didn't support device replace
on raid56, so we didn't fix the problem on the raid56 profile.
Currently, we implemented device replace for raid56, so we need
kick that problem out before we enable that function for raid56.

The fix method is very simple, we just increase the bio per-cpu
counter before we submit a raid56 io, and decrease the counter
when the raid56 io ends.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2014-12-03 10:18:47 +08:00

64 lines
2.2 KiB
C

/*
* Copyright (C) 2012 Fusion-io All rights reserved.
* Copyright (C) 2012 Intel Corp. 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.
*/
#ifndef __BTRFS_RAID56__
#define __BTRFS_RAID56__
static inline int nr_parity_stripes(struct map_lookup *map)
{
if (map->type & BTRFS_BLOCK_GROUP_RAID5)
return 1;
else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
return 2;
else
return 0;
}
static inline int nr_data_stripes(struct map_lookup *map)
{
return map->num_stripes - nr_parity_stripes(map);
}
#define RAID5_P_STRIPE ((u64)-2)
#define RAID6_Q_STRIPE ((u64)-1)
#define is_parity_stripe(x) (((x) == RAID5_P_STRIPE) || \
((x) == RAID6_Q_STRIPE))
struct btrfs_raid_bio;
struct btrfs_device;
int raid56_parity_recover(struct btrfs_root *root, struct bio *bio,
struct btrfs_bio *bbio, u64 *raid_map,
u64 stripe_len, int mirror_num, int generic_io);
int raid56_parity_write(struct btrfs_root *root, struct bio *bio,
struct btrfs_bio *bbio, u64 *raid_map,
u64 stripe_len);
struct btrfs_raid_bio *
raid56_parity_alloc_scrub_rbio(struct btrfs_root *root, struct bio *bio,
struct btrfs_bio *bbio, u64 *raid_map,
u64 stripe_len, struct btrfs_device *scrub_dev,
unsigned long *dbitmap, int stripe_nsectors);
void raid56_parity_add_scrub_pages(struct btrfs_raid_bio *rbio,
struct page *page, u64 logical);
void raid56_parity_submit_scrub_rbio(struct btrfs_raid_bio *rbio);
int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info);
void btrfs_free_stripe_hash_table(struct btrfs_fs_info *info);
#endif