/** * \file drm_atomic.h * Atomic operations used in the DRM which may or may not be provided by the OS. * * \author Eric Anholt <anholt@FreeBSD.org> */ /*- * Copyright 2004 Eric Anholt * Copyright 2013 Jung-uk Kim <jkim@FreeBSD.org> * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. */ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); typedef u_int atomic_t; typedef uint64_t atomic64_t; #define NB_BITS_PER_LONG (sizeof(long) * NBBY) #define BITS_TO_LONGS(x) howmany(x, NB_BITS_PER_LONG) #define atomic_read(p) atomic_load_acq_int(p) #define atomic_set(p, v) atomic_store_rel_int(p, v) #define atomic64_read(p) atomic_load_acq_64(p) #define atomic64_set(p, v) atomic_store_rel_64(p, v) #define atomic_add(v, p) atomic_add_int(p, v) #define atomic_sub(v, p) atomic_subtract_int(p, v) #define atomic_inc(p) atomic_add(1, p) #define atomic_dec(p) atomic_sub(1, p) #define atomic_add_return(v, p) (atomic_fetchadd_int(p, v) + (v)) #define atomic_sub_return(v, p) (atomic_fetchadd_int(p, -(v)) - (v)) #define atomic_inc_return(p) atomic_add_return(1, p) #define atomic_dec_return(p) atomic_sub_return(1, p) #define atomic_add_and_test(v, p) (atomic_add_return(v, p) == 0) #define atomic_sub_and_test(v, p) (atomic_sub_return(v, p) == 0) #define atomic_inc_and_test(p) (atomic_inc_return(p) == 0) #define atomic_dec_and_test(p) (atomic_dec_return(p) == 0) #define atomic_xchg(p, v) atomic_swap_int(p, v) #define atomic64_xchg(p, v) atomic_swap_64(p, v) #define __bit_word(b) ((b) / NB_BITS_PER_LONG) #define __bit_mask(b) (1UL << (b) % NB_BITS_PER_LONG) #define __bit_addr(p, b) ((volatile u_long *)(p) + __bit_word(b)) #define clear_bit(b, p) \ atomic_clear_long(__bit_addr(p, b), __bit_mask(b)) #define set_bit(b, p) \ atomic_set_long(__bit_addr(p, b), __bit_mask(b)) #define test_bit(b, p) \ ((*__bit_addr(p, b) & __bit_mask(b)) != 0) #define test_and_set_bit(b, p) \ (atomic_xchg((p), 1) != b) #define cmpxchg(ptr, old, new) \ (atomic_cmpset_int((volatile u_int *)(ptr),(old),(new)) ? (old) : (0)) #define atomic_inc_not_zero(p) atomic_inc(p) #define atomic_clear_mask(b, p) atomic_clear_int((p), (b)) static __inline u_long find_first_zero_bit(const u_long *p, u_long max) { u_long i, n; KASSERT(max % NB_BITS_PER_LONG == 0, ("invalid bitmap size %lu", max)); for (i = 0; i < max / NB_BITS_PER_LONG; i++) { n = ~p[i]; if (n != 0) return (i * NB_BITS_PER_LONG + ffsl(n) - 1); } return (max); } |