name : blockgroup_lock.h /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_BLOCKGROUP_LOCK_H #define _LINUX_BLOCKGROUP_LOCK_H /* * Per-blockgroup locking for ext2 and ext3. * * Simple hashed spinlocking. */ #include <linux/spinlock.h> #include <linux/cache.h> #ifdef CONFIG_SMP #define NR_BG_LOCKS (4 << ilog2(NR_CPUS < 32 ? NR_CPUS : 32)) #else #define NR_BG_LOCKS 1 #endif struct bgl_lock { spinlock_t lock; } ____cacheline_aligned_in_smp; struct blockgroup_lock { struct bgl_lock locks[NR_BG_LOCKS]; }; static inline void bgl_lock_init(struct blockgroup_lock *bgl) { int i; for (i = 0; i < NR_BG_LOCKS; i++) spin_lock_init(&bgl->locks[i].lock); } static inline spinlock_t * bgl_lock_ptr(struct blockgroup_lock *bgl, unsigned int block_group) { return &bgl->locks[block_group & (NR_BG_LOCKS-1)].lock; } #endif