This makes the function much simpler since the complex retry logic is now handled elsewhere. v2: use sizeof(void*) instead Signed-off-by: Christian König <christian.koenig@xxxxxxx> --- drivers/dma-buf/dma-resv.c | 112 +++++++++++++------------------------ 1 file changed, 40 insertions(+), 72 deletions(-) diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index 406150dea5e4..9b90bd9ac018 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -487,99 +487,67 @@ EXPORT_SYMBOL(dma_resv_copy_fences); * dma_resv_get_fences - Get an object's shared and exclusive * fences without update side lock held * @obj: the reservation object - * @pfence_excl: the returned exclusive fence (or NULL) - * @pshared_count: the number of shared fences returned - * @pshared: the array of shared fence ptrs returned (array is krealloc'd to + * @fence_excl: the returned exclusive fence (or NULL) + * @shared_count: the number of shared fences returned + * @shared: the array of shared fence ptrs returned (array is krealloc'd to * the required size, and must be freed by caller) * * Retrieve all fences from the reservation object. If the pointer for the * exclusive fence is not specified the fence is put into the array of the * shared fences as well. Returns either zero or -ENOMEM. */ -int dma_resv_get_fences(struct dma_resv *obj, struct dma_fence **pfence_excl, - unsigned int *pshared_count, - struct dma_fence ***pshared) +int dma_resv_get_fences(struct dma_resv *obj, struct dma_fence **fence_excl, + unsigned int *shared_count, struct dma_fence ***shared) { - struct dma_fence **shared = NULL; - struct dma_fence *fence_excl; - unsigned int shared_count; - int ret = 1; - - do { - struct dma_resv_list *fobj; - unsigned int i, seq; - size_t sz = 0; - - shared_count = i = 0; - - rcu_read_lock(); - seq = read_seqcount_begin(&obj->seq); + struct dma_resv_iter cursor; + struct dma_fence *fence; - fence_excl = dma_resv_excl_fence(obj); - if (fence_excl && !dma_fence_get_rcu(fence_excl)) - goto unlock; + *shared_count = 0; + *shared = NULL; - fobj = dma_resv_shared_list(obj); - if (fobj) - sz += sizeof(*shared) * fobj->shared_max; + if (fence_excl) + *fence_excl = NULL; - if (!pfence_excl && fence_excl) - sz += sizeof(*shared); + rcu_read_lock(); + dma_resv_iter_begin(&cursor, obj, true); + dma_resv_for_each_fence_unlocked(&cursor, fence) { - if (sz) { - struct dma_fence **nshared; + if (cursor.is_first) { + unsigned int count; - nshared = krealloc(shared, sz, - GFP_NOWAIT | __GFP_NOWARN); - if (!nshared) { - rcu_read_unlock(); + while (*shared_count) + dma_fence_put((*shared)[--(*shared_count)]); - dma_fence_put(fence_excl); - fence_excl = NULL; + if (fence_excl) + dma_fence_put(*fence_excl); - nshared = krealloc(shared, sz, GFP_KERNEL); - if (nshared) { - shared = nshared; - continue; - } + count = cursor.fences ? cursor.fences->shared_count : 0; + count += fence_excl ? 0 : 1; + rcu_read_unlock(); - ret = -ENOMEM; - break; - } - shared = nshared; - shared_count = fobj ? fobj->shared_count : 0; - for (i = 0; i < shared_count; ++i) { - shared[i] = rcu_dereference(fobj->shared[i]); - if (!dma_fence_get_rcu(shared[i])) - break; + /* Eventually re-allocate the array */ + *shared = krealloc_array(*shared, count, + sizeof(void *), + GFP_KERNEL); + if (count && !*shared) { + dma_resv_iter_end(&cursor); + return -ENOMEM; } + rcu_read_lock(); } - if (i != shared_count || read_seqcount_retry(&obj->seq, seq)) { - while (i--) - dma_fence_put(shared[i]); - dma_fence_put(fence_excl); - goto unlock; - } - - ret = 0; -unlock: - rcu_read_unlock(); - } while (ret); - - if (pfence_excl) - *pfence_excl = fence_excl; - else if (fence_excl) - shared[shared_count++] = fence_excl; + if (dma_resv_iter_is_exclusive(&cursor) && fence_excl) + *fence_excl = fence; + else + (*shared)[(*shared_count)++] = fence; - if (!shared_count) { - kfree(shared); - shared = NULL; + /* Don't drop the reference */ + fence = NULL; } + dma_resv_iter_end(&cursor); + rcu_read_unlock(); - *pshared_count = shared_count; - *pshared = shared; - return ret; + return 0; } EXPORT_SYMBOL_GPL(dma_resv_get_fences); -- 2.25.1