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path: root/drivers/dma-buf/reservation.c
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Diffstat (limited to 'drivers/dma-buf/reservation.c')
-rw-r--r--drivers/dma-buf/reservation.c99
1 files changed, 77 insertions, 22 deletions
diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c
index 393817e849ed..dec3a815455d 100644
--- a/drivers/dma-buf/reservation.c
+++ b/drivers/dma-buf/reservation.c
@@ -195,8 +195,7 @@ done:
if (old)
kfree_rcu(old, rcu);
- if (old_fence)
- dma_fence_put(old_fence);
+ dma_fence_put(old_fence);
}
/**
@@ -258,12 +257,71 @@ void reservation_object_add_excl_fence(struct reservation_object *obj,
dma_fence_put(rcu_dereference_protected(old->shared[i],
reservation_object_held(obj)));
- if (old_fence)
- dma_fence_put(old_fence);
+ dma_fence_put(old_fence);
}
EXPORT_SYMBOL(reservation_object_add_excl_fence);
/**
+* reservation_object_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. Both src->lock as well as dst-lock must be
+* held.
+*/
+int reservation_object_copy_fences(struct reservation_object *dst,
+ struct reservation_object *src)
+{
+ struct reservation_object_list *src_list, *dst_list;
+ struct dma_fence *old, *new;
+ size_t size;
+ unsigned i;
+
+ src_list = reservation_object_get_list(src);
+
+ if (src_list) {
+ size = offsetof(typeof(*src_list),
+ shared[src_list->shared_count]);
+ dst_list = kmalloc(size, GFP_KERNEL);
+ if (!dst_list)
+ return -ENOMEM;
+
+ dst_list->shared_count = src_list->shared_count;
+ dst_list->shared_max = src_list->shared_count;
+ for (i = 0; i < src_list->shared_count; ++i)
+ dst_list->shared[i] =
+ dma_fence_get(src_list->shared[i]);
+ } else {
+ dst_list = NULL;
+ }
+
+ kfree(dst->staged);
+ dst->staged = NULL;
+
+ src_list = reservation_object_get_list(dst);
+
+ old = reservation_object_get_excl(dst);
+ new = reservation_object_get_excl(src);
+
+ dma_fence_get(new);
+
+ preempt_disable();
+ write_seqcount_begin(&dst->seq);
+ /* write_seqcount_begin provides the necessary memory barrier */
+ RCU_INIT_POINTER(dst->fence_excl, new);
+ RCU_INIT_POINTER(dst->fence, dst_list);
+ write_seqcount_end(&dst->seq);
+ preempt_enable();
+
+ if (src_list)
+ kfree_rcu(src_list, rcu);
+ dma_fence_put(old);
+
+ return 0;
+}
+EXPORT_SYMBOL(reservation_object_copy_fences);
+
+/**
* reservation_object_get_fences_rcu - Get an object's shared and exclusive
* fences without update side lock held
* @obj: the reservation object
@@ -373,12 +431,25 @@ long reservation_object_wait_timeout_rcu(struct reservation_object *obj,
long ret = timeout ? timeout : 1;
retry:
- fence = NULL;
shared_count = 0;
seq = read_seqcount_begin(&obj->seq);
rcu_read_lock();
- if (wait_all) {
+ fence = rcu_dereference(obj->fence_excl);
+ if (fence && !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) {
+ if (!dma_fence_get_rcu(fence))
+ goto unlock_retry;
+
+ if (dma_fence_is_signaled(fence)) {
+ dma_fence_put(fence);
+ fence = NULL;
+ }
+
+ } else {
+ fence = NULL;
+ }
+
+ if (!fence && wait_all) {
struct reservation_object_list *fobj =
rcu_dereference(obj->fence);
@@ -405,22 +476,6 @@ retry:
}
}
- if (!shared_count) {
- struct dma_fence *fence_excl = rcu_dereference(obj->fence_excl);
-
- if (fence_excl &&
- !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
- &fence_excl->flags)) {
- if (!dma_fence_get_rcu(fence_excl))
- goto unlock_retry;
-
- if (dma_fence_is_signaled(fence_excl))
- dma_fence_put(fence_excl);
- else
- fence = fence_excl;
- }
- }
-
rcu_read_unlock();
if (fence) {
if (read_seqcount_retry(&obj->seq, seq)) {