From 94eb1e10a34d3c7fc42208faaa4954fe482ac091 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 12 Jul 2019 09:03:13 +0100 Subject: [PATCH] dma-buf: Expand reservation_list to fill allocation MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Since kmalloc() will round up the allocation to the next slab size or page, it will normally return a pointer to a memory block bigger than we asked for. We can query for the actual size of the allocated block using ksize() and expand our variable size reservation_list to take advantage of that extra space. Signed-off-by: Chris Wilson Cc: Christian König Cc: Michel Dänzer Reviewed-by: Michel Dänzer Reviewed-by: Christian König Link: https://patchwork.freedesktop.org/patch/msgid/20190712080314.21018-1-chris@chris-wilson.co.uk --- drivers/dma-buf/reservation.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index a6ac2b3a0185..80ecc1283d15 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -153,7 +153,9 @@ int reservation_object_reserve_shared(struct reservation_object *obj, RCU_INIT_POINTER(new->shared[j++], fence); } new->shared_count = j; - new->shared_max = max; + new->shared_max = + (ksize(new) - offsetof(typeof(*new), shared)) / + sizeof(*new->shared); preempt_disable(); write_seqcount_begin(&obj->seq); @@ -169,7 +171,7 @@ int reservation_object_reserve_shared(struct reservation_object *obj, return 0; /* Drop the references to the signaled fences */ - for (i = k; i < new->shared_max; ++i) { + for (i = k; i < max; ++i) { struct dma_fence *fence; fence = rcu_dereference_protected(new->shared[i], -- 2.11.0