A simpler version of the iterator to be used when the dma_resv object is locked.
Signed-off-by: Christian König christian.koenig@amd.com --- drivers/dma-buf/dma-resv.c | 38 ++++++++++++++++++++++++++++++++++++++ include/linux/dma-resv.h | 18 ++++++++++++++++++ 2 files changed, 56 insertions(+)
diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index 213a9b7251ca..8cbccaae169d 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -323,6 +323,44 @@ void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence) } EXPORT_SYMBOL(dma_resv_add_excl_fence);
+/** + * dma_resv_walk - walk over fences in a dma_resv obj + * @obj: the dma_resv object + * @cursor: cursor to record the current position + * @all_fences: true returns also the shared fences + * @first: if we should start over + * + * Return all the fences in the dma_resv object while holding the + * dma_resv::lock. + */ +struct dma_fence *dma_resv_walk(struct dma_resv *obj, + struct dma_resv_cursor *cursor, + bool all_fences, bool first) +{ + dma_resv_assert_held(obj); + + cursor->is_first = first; + if (first) { + struct dma_fence *fence; + + cursor->index = -1; + cursor->fences = dma_resv_shared_list(obj); + cursor->is_exclusive = true; + + fence = dma_resv_excl_fence(obj); + if (fence) + return fence; + } + + if (!all_fences || !cursor->fences || + ++cursor->index >= cursor->fences->shared_count) + return NULL; + + return rcu_dereference_protected(cursor->fences->shared[cursor->index], + dma_resv_held(obj)); +} +EXPORT_SYMBOL_GPL(dma_resv_walk); + /** * dma_resv_walk_unlocked - walk over fences in a dma_resv obj * @obj: the dma_resv object diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h index f5b91c292ee0..6f9bb7e4c538 100644 --- a/include/linux/dma-resv.h +++ b/include/linux/dma-resv.h @@ -165,6 +165,21 @@ struct dma_resv_cursor { bool is_exclusive; };
+/** + * dma_resv_for_each_fence - fence iterator + * @obj: a dma_resv object pointer + * @cursor: a struct dma_resv_cursor pointer + * @all_fences: true if all fences should be returned + * @fence: the current fence + * + * Iterate over the fences in a struct dma_resv object while holding the + * dma_resv::lock. @all_fences controls if the shared fences are returned as + * well. + */ +#define dma_resv_for_each_fence(obj, cursor, all_fences, fence) \ + for (fence = dma_resv_walk(obj, cursor, all_fences, true); fence; \ + fence = dma_resv_walk(obj, cursor, all_fences, false)) + /** * dma_resv_for_each_fence_unlocked - fence iterator * @obj: a dma_resv object pointer @@ -399,6 +414,9 @@ void dma_resv_fini(struct dma_resv *obj); int dma_resv_reserve_shared(struct dma_resv *obj, unsigned int num_fences); void dma_resv_add_shared_fence(struct dma_resv *obj, struct dma_fence *fence); void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence); +struct dma_fence *dma_resv_walk(struct dma_resv *obj, + struct dma_resv_cursor *cursor, + bool first, bool all_fences); struct dma_fence *dma_resv_walk_unlocked(struct dma_resv *obj, struct dma_resv_cursor *cursor, bool first, bool all_fences);