diff options
-rw-r--r-- | drivers/dma-buf/dma-resv.c | 128 |
1 files changed, 65 insertions, 63 deletions
diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index 6ddbeb5dfbf6..87f5d82d992a 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: MIT /* * Copyright (C) 2012-2014 Canonical Ltd (Maarten Lankhorst) * @@ -92,49 +93,6 @@ static void dma_resv_list_free(struct dma_resv_list *list) kfree_rcu(list, rcu); } -#if IS_ENABLED(CONFIG_LOCKDEP) -static int __init dma_resv_lockdep(void) -{ - struct mm_struct *mm = mm_alloc(); - struct ww_acquire_ctx ctx; - struct dma_resv obj; - struct address_space mapping; - int ret; - - if (!mm) - return -ENOMEM; - - dma_resv_init(&obj); - address_space_init_once(&mapping); - - mmap_read_lock(mm); - ww_acquire_init(&ctx, &reservation_ww_class); - ret = dma_resv_lock(&obj, &ctx); - if (ret == -EDEADLK) - dma_resv_lock_slow(&obj, &ctx); - fs_reclaim_acquire(GFP_KERNEL); - /* for unmap_mapping_range on trylocked buffer objects in shrinkers */ - i_mmap_lock_write(&mapping); - i_mmap_unlock_write(&mapping); -#ifdef CONFIG_MMU_NOTIFIER - lock_map_acquire(&__mmu_notifier_invalidate_range_start_map); - __dma_fence_might_wait(); - lock_map_release(&__mmu_notifier_invalidate_range_start_map); -#else - __dma_fence_might_wait(); -#endif - fs_reclaim_release(GFP_KERNEL); - ww_mutex_unlock(&obj.lock); - ww_acquire_fini(&ctx); - mmap_read_unlock(mm); - - mmput(mm); - - return 0; -} -subsys_initcall(dma_resv_lockdep); -#endif - /** * dma_resv_init - initialize a reservation object * @obj: the reservation object @@ -196,9 +154,7 @@ int dma_resv_reserve_shared(struct dma_resv *obj, unsigned int num_fences) if (old && old->shared_max) { if ((old->shared_count + num_fences) <= old->shared_max) return 0; - else - max = max(old->shared_count + num_fences, - old->shared_max * 2); + max = max(old->shared_count + num_fences, old->shared_max * 2); } else { max = max(4ul, roundup_pow_of_two(num_fences)); } @@ -337,17 +293,17 @@ void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence) EXPORT_SYMBOL(dma_resv_add_excl_fence); /** -* dma_resv_copy_fences - Copy all fences from src to dst. -* @dst: the destination reservation object -* @src: the source reservation object -* -* Copy all fences from src to dst. dst-lock must be held. -*/ + * dma_resv_copy_fences - Copy all fences from src to dst. + * @dst: the destination reservation object + * @src: the source reservation object + * + * Copy all fences from src to dst. dst-lock must be held. + */ int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src) { struct dma_resv_list *src_list, *dst_list; struct dma_fence *old, *new; - unsigned i; + unsigned int i; dma_resv_assert_held(dst); @@ -356,7 +312,7 @@ int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src) retry: if (src_list) { - unsigned shared_count = src_list->shared_count; + unsigned int shared_count = src_list->shared_count; rcu_read_unlock(); @@ -373,6 +329,7 @@ retry: dst_list->shared_count = 0; for (i = 0; i < src_list->shared_count; ++i) { + struct dma_fence __rcu **dst; struct dma_fence *fence; fence = rcu_dereference(src_list->shared[i]); @@ -391,7 +348,8 @@ retry: continue; } - rcu_assign_pointer(dst_list->shared[dst_list->shared_count++], fence); + dst = &dst_list->shared[dst_list->shared_count++]; + rcu_assign_pointer(*dst, fence); } } else { dst_list = NULL; @@ -431,7 +389,7 @@ EXPORT_SYMBOL(dma_resv_copy_fences); */ int dma_resv_get_fences_rcu(struct dma_resv *obj, struct dma_fence **pfence_excl, - unsigned *pshared_count, + unsigned int *pshared_count, struct dma_fence ***pshared) { struct dma_fence **shared = NULL; @@ -533,9 +491,9 @@ long dma_resv_wait_timeout_rcu(struct dma_resv *obj, bool wait_all, bool intr, unsigned long timeout) { - struct dma_fence *fence; - unsigned seq, shared_count; long ret = timeout ? timeout : 1; + unsigned int seq, shared_count; + struct dma_fence *fence; int i; retry: @@ -565,8 +523,9 @@ retry: shared_count = fobj->shared_count; for (i = 0; !fence && i < shared_count; ++i) { - struct dma_fence *lfence = rcu_dereference(fobj->shared[i]); + struct dma_fence *lfence; + lfence = rcu_dereference(fobj->shared[i]); if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &lfence->flags)) continue; @@ -633,7 +592,7 @@ static inline int dma_resv_test_signaled_single(struct dma_fence *passed_fence) */ bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all) { - unsigned seq, shared_count; + unsigned int seq, shared_count; int ret; rcu_read_lock(); @@ -643,16 +602,16 @@ retry: seq = read_seqcount_begin(&obj->seq); if (test_all) { - unsigned i; - struct dma_resv_list *fobj = rcu_dereference(obj->fence); + unsigned int i; if (fobj) shared_count = fobj->shared_count; for (i = 0; i < shared_count; ++i) { - struct dma_fence *fence = rcu_dereference(fobj->shared[i]); + struct dma_fence *fence; + fence = rcu_dereference(fobj->shared[i]); ret = dma_resv_test_signaled_single(fence); if (ret < 0) goto retry; @@ -681,3 +640,46 @@ retry: return ret; } EXPORT_SYMBOL_GPL(dma_resv_test_signaled_rcu); + +#if IS_ENABLED(CONFIG_LOCKDEP) +static int __init dma_resv_lockdep(void) +{ + struct mm_struct *mm = mm_alloc(); + struct ww_acquire_ctx ctx; + struct dma_resv obj; + struct address_space mapping; + int ret; + + if (!mm) + return -ENOMEM; + + dma_resv_init(&obj); + address_space_init_once(&mapping); + + mmap_read_lock(mm); + ww_acquire_init(&ctx, &reservation_ww_class); + ret = dma_resv_lock(&obj, &ctx); + if (ret == -EDEADLK) + dma_resv_lock_slow(&obj, &ctx); + fs_reclaim_acquire(GFP_KERNEL); + /* for unmap_mapping_range on trylocked buffer objects in shrinkers */ + i_mmap_lock_write(&mapping); + i_mmap_unlock_write(&mapping); +#ifdef CONFIG_MMU_NOTIFIER + lock_map_acquire(&__mmu_notifier_invalidate_range_start_map); + __dma_fence_might_wait(); + lock_map_release(&__mmu_notifier_invalidate_range_start_map); +#else + __dma_fence_might_wait(); +#endif + fs_reclaim_release(GFP_KERNEL); + ww_mutex_unlock(&obj.lock); + ww_acquire_fini(&ctx); + mmap_read_unlock(mm); + + mmput(mm); + + return 0; +} +subsys_initcall(dma_resv_lockdep); +#endif |