On Wed, Jun 02, 2021 at 04:03:59PM +0200, Christian König wrote:
> dma_resv_lockdep() seems to have some space/tab mixups. Fix that and
> move the function to the end of the file.
>
> Also fix some minor things checkpatch.pl pointed out while at it.
>
> No functional change.
>
> Signed-off-by: Christian König <christian.koenig@xxxxxxx>
Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
> ---
> drivers/dma-buf/dma-resv.c | 128 +++++++++++++++++++------------------
> 1 file changed, 65 insertions(+), 63 deletions(-)
>
> diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c
> index 6ddbeb5dfbf6..87f5d82d992a 100644
> --- a/drivers/dma-buf/dma-resv.c
> +++ b/drivers/dma-buf/dma-resv.c
> @@ -1,3 +1,4 @@
> +// SPDX-License-Identifier: MIT
> /*
> * Copyright (C) 2012-2014 Canonical Ltd (Maarten Lankhorst)
> *
> @@ -92,49 +93,6 @@ static void dma_resv_list_free(struct dma_resv_list *list)
> kfree_rcu(list, rcu);
> }
>
> -#if IS_ENABLED(CONFIG_LOCKDEP)
> -static int __init dma_resv_lockdep(void)
> -{
> - struct mm_struct *mm = mm_alloc();
> - struct ww_acquire_ctx ctx;
> - struct dma_resv obj;
> - struct address_space mapping;
> - int ret;
> -
> - if (!mm)
> - return -ENOMEM;
> -
> - dma_resv_init(&obj);
> - address_space_init_once(&mapping);
> -
> - mmap_read_lock(mm);
> - ww_acquire_init(&ctx, &reservation_ww_class);
> - ret = dma_resv_lock(&obj, &ctx);
> - if (ret == -EDEADLK)
> - dma_resv_lock_slow(&obj, &ctx);
> - fs_reclaim_acquire(GFP_KERNEL);
> - /* for unmap_mapping_range on trylocked buffer objects in shrinkers */
> - i_mmap_lock_write(&mapping);
> - i_mmap_unlock_write(&mapping);
> -#ifdef CONFIG_MMU_NOTIFIER
> - lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
> - __dma_fence_might_wait();
> - lock_map_release(&__mmu_notifier_invalidate_range_start_map);
> -#else
> - __dma_fence_might_wait();
> -#endif
> - fs_reclaim_release(GFP_KERNEL);
> - ww_mutex_unlock(&obj.lock);
> - ww_acquire_fini(&ctx);
> - mmap_read_unlock(mm);
> -
> - mmput(mm);
> -
> - return 0;
> -}
> -subsys_initcall(dma_resv_lockdep);
> -#endif
> -
> /**
> * dma_resv_init - initialize a reservation object
> * @obj: the reservation object
> @@ -196,9 +154,7 @@ int dma_resv_reserve_shared(struct dma_resv *obj, unsigned int num_fences)
> if (old && old->shared_max) {
> if ((old->shared_count + num_fences) <= old->shared_max)
> return 0;
> - else
> - max = max(old->shared_count + num_fences,
> - old->shared_max * 2);
> + max = max(old->shared_count + num_fences, old->shared_max * 2);
> } else {
> max = max(4ul, roundup_pow_of_two(num_fences));
> }
> @@ -337,17 +293,17 @@ void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence)
> EXPORT_SYMBOL(dma_resv_add_excl_fence);
>
> /**
> -* dma_resv_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. dst-lock must be held.
> -*/
> + * dma_resv_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. dst-lock must be held.
> + */
> int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src)
> {
> struct dma_resv_list *src_list, *dst_list;
> struct dma_fence *old, *new;
> - unsigned i;
> + unsigned int i;
>
> dma_resv_assert_held(dst);
>
> @@ -356,7 +312,7 @@ int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src)
>
> retry:
> if (src_list) {
> - unsigned shared_count = src_list->shared_count;
> + unsigned int shared_count = src_list->shared_count;
>
> rcu_read_unlock();
>
> @@ -373,6 +329,7 @@ int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src)
>
> dst_list->shared_count = 0;
> for (i = 0; i < src_list->shared_count; ++i) {
> + struct dma_fence __rcu **dst;
> struct dma_fence *fence;
>
> fence = rcu_dereference(src_list->shared[i]);
> @@ -391,7 +348,8 @@ int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src)
> continue;
> }
>
> - rcu_assign_pointer(dst_list->shared[dst_list->shared_count++], fence);
> + dst = &dst_list->shared[dst_list->shared_count++];
> + rcu_assign_pointer(*dst, fence);
> }
> } else {
> dst_list = NULL;
> @@ -431,7 +389,7 @@ EXPORT_SYMBOL(dma_resv_copy_fences);
> */
> int dma_resv_get_fences_rcu(struct dma_resv *obj,
> struct dma_fence **pfence_excl,
> - unsigned *pshared_count,
> + unsigned int *pshared_count,
> struct dma_fence ***pshared)
> {
> struct dma_fence **shared = NULL;
> @@ -533,9 +491,9 @@ long dma_resv_wait_timeout_rcu(struct dma_resv *obj,
> bool wait_all, bool intr,
> unsigned long timeout)
> {
> - struct dma_fence *fence;
> - unsigned seq, shared_count;
> long ret = timeout ? timeout : 1;
> + unsigned int seq, shared_count;
> + struct dma_fence *fence;
> int i;
>
> retry:
> @@ -565,8 +523,9 @@ long dma_resv_wait_timeout_rcu(struct dma_resv *obj,
> shared_count = fobj->shared_count;
>
> for (i = 0; !fence && i < shared_count; ++i) {
> - struct dma_fence *lfence = rcu_dereference(fobj->shared[i]);
> + struct dma_fence *lfence;
>
> + lfence = rcu_dereference(fobj->shared[i]);
> if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
> &lfence->flags))
> continue;
> @@ -633,7 +592,7 @@ static inline int dma_resv_test_signaled_single(struct dma_fence *passed_fence)
> */
> bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all)
> {
> - unsigned seq, shared_count;
> + unsigned int seq, shared_count;
> int ret;
>
> rcu_read_lock();
> @@ -643,16 +602,16 @@ bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all)
> seq = read_seqcount_begin(&obj->seq);
>
> if (test_all) {
> - unsigned i;
> -
> struct dma_resv_list *fobj = rcu_dereference(obj->fence);
> + unsigned int i;
>
> if (fobj)
> shared_count = fobj->shared_count;
>
> for (i = 0; i < shared_count; ++i) {
> - struct dma_fence *fence = rcu_dereference(fobj->shared[i]);
> + struct dma_fence *fence;
>
> + fence = rcu_dereference(fobj->shared[i]);
> ret = dma_resv_test_signaled_single(fence);
> if (ret < 0)
> goto retry;
> @@ -681,3 +640,46 @@ bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all)
> return ret;
> }
> EXPORT_SYMBOL_GPL(dma_resv_test_signaled_rcu);
> +
> +#if IS_ENABLED(CONFIG_LOCKDEP)
> +static int __init dma_resv_lockdep(void)
> +{
> + struct mm_struct *mm = mm_alloc();
> + struct ww_acquire_ctx ctx;
> + struct dma_resv obj;
> + struct address_space mapping;
> + int ret;
> +
> + if (!mm)
> + return -ENOMEM;
> +
> + dma_resv_init(&obj);
> + address_space_init_once(&mapping);
> +
> + mmap_read_lock(mm);
> + ww_acquire_init(&ctx, &reservation_ww_class);
> + ret = dma_resv_lock(&obj, &ctx);
> + if (ret == -EDEADLK)
> + dma_resv_lock_slow(&obj, &ctx);
> + fs_reclaim_acquire(GFP_KERNEL);
> + /* for unmap_mapping_range on trylocked buffer objects in shrinkers */
> + i_mmap_lock_write(&mapping);
> + i_mmap_unlock_write(&mapping);
> +#ifdef CONFIG_MMU_NOTIFIER
> + lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
> + __dma_fence_might_wait();
> + lock_map_release(&__mmu_notifier_invalidate_range_start_map);
> +#else
> + __dma_fence_might_wait();
> +#endif
> + fs_reclaim_release(GFP_KERNEL);
> + ww_mutex_unlock(&obj.lock);
> + ww_acquire_fini(&ctx);
> + mmap_read_unlock(mm);
> +
> + mmput(mm);
> +
> + return 0;
> +}
> +subsys_initcall(dma_resv_lockdep);
> +#endif
> --
> 2.25.1
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
