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 | 33 +++++++++++++++++++++++++++++++++ include/linux/dma-resv.h | 17 +++++++++++++++++ 2 files changed, 50 insertions(+)
diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index 3e77cad2c9d4..a3c79a99fb44 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -384,6 +384,39 @@ struct dma_fence *dma_resv_iter_walk_unlocked(struct dma_resv_iter *cursor, } EXPORT_SYMBOL_GPL(dma_resv_iter_walk_unlocked);
+/** + * dma_resv_iter_walk - walk over fences in a dma_resv obj + * @cursor: cursor to record the current position + * @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_iter_walk(struct dma_resv_iter *cursor, bool first) +{ + dma_resv_assert_held(cursor->obj); + + cursor->is_first = first; + if (first) { + struct dma_fence *fence; + + cursor->index = -1; + cursor->fences = dma_resv_shared_list(cursor->obj); + + fence = dma_resv_excl_fence(cursor->obj); + if (fence) + return fence; + } + + if (!cursor->all_fences || !cursor->fences || + ++cursor->index >= cursor->fences->shared_count) + return NULL; + + return rcu_dereference_protected(cursor->fences->shared[cursor->index], + dma_resv_held(cursor->obj)); +} +EXPORT_SYMBOL_GPL(dma_resv_iter_walk); + /** * dma_resv_copy_fences - Copy all fences from src to dst. * @dst: the destination reservation object diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h index 693d16117153..8c968f8c9d33 100644 --- a/include/linux/dma-resv.h +++ b/include/linux/dma-resv.h @@ -179,6 +179,7 @@ struct dma_resv_iter {
struct dma_fence *dma_resv_iter_walk_unlocked(struct dma_resv_iter *cursor, bool first); +struct dma_fence *dma_resv_iter_walk(struct dma_resv_iter *cursor, bool first);
/** * dma_resv_iter_begin - initialize a dma_resv_iter object @@ -233,6 +234,22 @@ static inline bool dma_resv_iter_is_exclusive(struct dma_resv_iter *cursor) for (fence = dma_resv_iter_walk_unlocked(cursor, true); \ fence; fence = dma_resv_iter_walk_unlocked(cursor, false))
+/** + * dma_resv_for_each_fence - fence iterator + * @cursor: a struct dma_resv_iter pointer + * @obj: a dma_resv object 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. The cursor initialisation is part of the iterator. + */ +#define dma_resv_for_each_fence(cursor, obj, all_fences, fence) \ + for (dma_resv_iter_begin(cursor, obj, all_fences), \ + fence = dma_resv_iter_walk(cursor, true); fence; \ + fence = dma_resv_iter_walk(cursor, false)) + #define dma_resv_held(obj) lockdep_is_held(&(obj)->lock.base) #define dma_resv_assert_held(obj) lockdep_assert_held(&(obj)->lock.base)