diff options
Diffstat (limited to 'drivers/dma-buf')
-rw-r--r-- | drivers/dma-buf/dma-buf.c | 6 | ||||
-rw-r--r-- | drivers/dma-buf/reservation.c | 58 |
2 files changed, 40 insertions, 24 deletions
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index bc1cb284111c..1792385405f0 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -351,13 +351,13 @@ static inline int is_dma_buf_file(struct file *file) * * 2. Userspace passes this file-descriptors to all drivers it wants this buffer * to share with: First the filedescriptor is converted to a &dma_buf using - * dma_buf_get(). The the buffer is attached to the device using + * dma_buf_get(). Then the buffer is attached to the device using * dma_buf_attach(). * * Up to this stage the exporter is still free to migrate or reallocate the * backing storage. * - * 3. Once the buffer is attached to all devices userspace can inniate DMA + * 3. Once the buffer is attached to all devices userspace can initiate DMA * access to the shared buffer. In the kernel this is done by calling * dma_buf_map_attachment() and dma_buf_unmap_attachment(). * @@ -617,7 +617,7 @@ EXPORT_SYMBOL_GPL(dma_buf_detach); * Returns sg_table containing the scatterlist to be returned; returns ERR_PTR * on error. May return -EINTR if it is interrupted by a signal. * - * A mapping must be unmapped again using dma_buf_map_attachment(). Note that + * A mapping must be unmapped by using dma_buf_unmap_attachment(). Note that * the underlying backing storage is pinned for as long as a mapping exists, * therefore users/importers should not hold onto a mapping for undue amounts of * time. diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index b44d9d7db347..b759a569b7b8 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -104,7 +104,8 @@ reservation_object_add_shared_inplace(struct reservation_object *obj, struct reservation_object_list *fobj, struct dma_fence *fence) { - u32 i; + struct dma_fence *signaled = NULL; + u32 i, signaled_idx; dma_fence_get(fence); @@ -126,17 +127,28 @@ reservation_object_add_shared_inplace(struct reservation_object *obj, dma_fence_put(old_fence); return; } + + if (!signaled && dma_fence_is_signaled(old_fence)) { + signaled = old_fence; + signaled_idx = i; + } } /* * memory barrier is added by write_seqcount_begin, * fobj->shared_count is protected by this lock too */ - RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); - fobj->shared_count++; + if (signaled) { + RCU_INIT_POINTER(fobj->shared[signaled_idx], fence); + } else { + RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); + fobj->shared_count++; + } write_seqcount_end(&obj->seq); preempt_enable(); + + dma_fence_put(signaled); } static void @@ -145,8 +157,7 @@ reservation_object_add_shared_replace(struct reservation_object *obj, struct reservation_object_list *fobj, struct dma_fence *fence) { - unsigned i; - struct dma_fence *old_fence = NULL; + unsigned i, j, k; dma_fence_get(fence); @@ -162,24 +173,21 @@ reservation_object_add_shared_replace(struct reservation_object *obj, * references from the old struct are carried over to * the new. */ - fobj->shared_count = old->shared_count; - - for (i = 0; i < old->shared_count; ++i) { + for (i = 0, j = 0, k = fobj->shared_max; i < old->shared_count; ++i) { struct dma_fence *check; check = rcu_dereference_protected(old->shared[i], reservation_object_held(obj)); - if (!old_fence && check->context == fence->context) { - old_fence = check; - RCU_INIT_POINTER(fobj->shared[i], fence); - } else - RCU_INIT_POINTER(fobj->shared[i], check); - } - if (!old_fence) { - RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); - fobj->shared_count++; + if (check->context == fence->context || + dma_fence_is_signaled(check)) + RCU_INIT_POINTER(fobj->shared[--k], check); + else + RCU_INIT_POINTER(fobj->shared[j++], check); } + fobj->shared_count = j; + RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); + fobj->shared_count++; done: preempt_disable(); @@ -192,10 +200,18 @@ done: write_seqcount_end(&obj->seq); preempt_enable(); - if (old) - kfree_rcu(old, rcu); + if (!old) + return; - dma_fence_put(old_fence); + /* Drop the references to the signaled fences */ + for (i = k; i < fobj->shared_max; ++i) { + struct dma_fence *f; + + f = rcu_dereference_protected(fobj->shared[i], + reservation_object_held(obj)); + dma_fence_put(f); + } + kfree_rcu(old, rcu); } /** @@ -318,7 +334,7 @@ retry: continue; } - dst_list->shared[dst_list->shared_count++] = fence; + rcu_assign_pointer(dst_list->shared[dst_list->shared_count++], fence); } } else { dst_list = NULL; |