projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 1da177e4 LT |
2 | #ifndef _LINUX_BLOCKGROUP_LOCK_H |
| 3 | #define _LINUX_BLOCKGROUP_LOCK_H | |
| 4 | /* | |
| 5 | * Per-blockgroup locking for ext2 and ext3. | |
| 6 | * | |
| 7 | * Simple hashed spinlocking. | |
| 8 | */ | |
| 9 | ||
| 1da177e4 LT |
10 | #include <linux/spinlock.h> |
| 11 | #include <linux/cache.h> | |
| 12 | ||
| 13 | #ifdef CONFIG_SMP | |
| 7c5f6b32 | 14 | #define NR_BG_LOCKS (4 << ilog2(NR_CPUS < 32 ? NR_CPUS : 32)) |
| 1da177e4 | 15 | #else |
| 1da177e4 | 16 | #define NR_BG_LOCKS 1 |
| 7c5f6b32 | 17 | #endif |
| 1da177e4 LT |
18 | |
| 19 | struct bgl_lock { | |
| 20 | spinlock_t lock; | |
| 21 | } ____cacheline_aligned_in_smp; | |
| 22 | ||
| 23 | struct blockgroup_lock { | |
| 24 | struct bgl_lock locks[NR_BG_LOCKS]; | |
| 25 | }; | |
| 26 | ||
| 27 | static inline void bgl_lock_init(struct blockgroup_lock *bgl) | |
| 28 | { | |
| 29 | int i; | |
| 30 | ||
| 31 | for (i = 0; i < NR_BG_LOCKS; i++) | |
| 32 | spin_lock_init(&bgl->locks[i].lock); | |
| 33 | } | |
| 34 | ||
| c644f0e4 PE |
35 | static inline spinlock_t * |
| 36 | bgl_lock_ptr(struct blockgroup_lock *bgl, unsigned int block_group) | |
| 37 | { | |
| 9e5ab85d | 38 | return &bgl->locks[block_group & (NR_BG_LOCKS-1)].lock; |
| c644f0e4 | 39 | } |
| 1da177e4 LT |
40 | |
| 41 | #endif |