Replace all drm-shmem locks with a GEM reservation lock. This makes locks consistent with dma-buf locking convention where importers are responsible for holding reservation lock for all operations performed over dma-bufs, preventing deadlock between dma-buf importers and exporters. Suggested-by: Daniel Vetter <daniel@xxxxxxxx> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx> --- drivers/gpu/drm/drm_gem_shmem_helper.c | 184 +++++++----------- drivers/gpu/drm/lima/lima_gem.c | 8 +- drivers/gpu/drm/panfrost/panfrost_drv.c | 7 +- .../gpu/drm/panfrost/panfrost_gem_shrinker.c | 6 +- drivers/gpu/drm/panfrost/panfrost_mmu.c | 19 +- include/drm/drm_gem_shmem_helper.h | 14 +- 6 files changed, 95 insertions(+), 143 deletions(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 801033b48893..d6e62f228989 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -86,8 +86,6 @@ __drm_gem_shmem_create(struct drm_device *dev, size_t size, bool private) if (ret) goto err_release; - mutex_init(&shmem->pages_lock); - mutex_init(&shmem->vmap_lock); INIT_LIST_HEAD(&shmem->madv_list); if (!private) { @@ -139,11 +137,13 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) { struct drm_gem_object *obj = &shmem->base; - WARN_ON(shmem->vmap_use_count); - if (obj->import_attach) { drm_prime_gem_destroy(obj, shmem->sgt); } else { + dma_resv_lock(shmem->base.resv, NULL); + + WARN_ON(shmem->vmap_use_count); + if (shmem->sgt) { dma_unmap_sgtable(obj->dev->dev, shmem->sgt, DMA_BIDIRECTIONAL, 0); @@ -152,18 +152,18 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) } if (shmem->pages) drm_gem_shmem_put_pages(shmem); - } - WARN_ON(shmem->pages_use_count); + WARN_ON(shmem->pages_use_count); + + dma_resv_unlock(shmem->base.resv); + } drm_gem_object_release(obj); - mutex_destroy(&shmem->pages_lock); - mutex_destroy(&shmem->vmap_lock); kfree(shmem); } EXPORT_SYMBOL_GPL(drm_gem_shmem_free); -static int drm_gem_shmem_get_pages_locked(struct drm_gem_shmem_object *shmem) +static int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem) { struct drm_gem_object *obj = &shmem->base; struct page **pages; @@ -194,35 +194,17 @@ static int drm_gem_shmem_get_pages_locked(struct drm_gem_shmem_object *shmem) } /* - * drm_gem_shmem_get_pages - Allocate backing pages for a shmem GEM object + * drm_gem_shmem_put_pages - Decrease use count on the backing pages for a shmem GEM object * @shmem: shmem GEM object * - * This function makes sure that backing pages exists for the shmem GEM object - * and increases the use count. - * - * Returns: - * 0 on success or a negative error code on failure. + * This function decreases the use count and puts the backing pages when use drops to zero. */ -int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem) -{ - int ret; - - WARN_ON(shmem->base.import_attach); - - ret = mutex_lock_interruptible(&shmem->pages_lock); - if (ret) - return ret; - ret = drm_gem_shmem_get_pages_locked(shmem); - mutex_unlock(&shmem->pages_lock); - - return ret; -} -EXPORT_SYMBOL(drm_gem_shmem_get_pages); - -static void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem) +void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem) { struct drm_gem_object *obj = &shmem->base; + dma_resv_assert_held(shmem->base.resv); + if (WARN_ON_ONCE(!shmem->pages_use_count)) return; @@ -239,19 +221,6 @@ static void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem) shmem->pages_mark_accessed_on_put); shmem->pages = NULL; } - -/* - * drm_gem_shmem_put_pages - Decrease use count on the backing pages for a shmem GEM object - * @shmem: shmem GEM object - * - * This function decreases the use count and puts the backing pages when use drops to zero. - */ -void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem) -{ - mutex_lock(&shmem->pages_lock); - drm_gem_shmem_put_pages_locked(shmem); - mutex_unlock(&shmem->pages_lock); -} EXPORT_SYMBOL(drm_gem_shmem_put_pages); /** @@ -266,6 +235,8 @@ EXPORT_SYMBOL(drm_gem_shmem_put_pages); */ int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem) { + dma_resv_assert_held(shmem->base.resv); + WARN_ON(shmem->base.import_attach); return drm_gem_shmem_get_pages(shmem); @@ -281,14 +252,31 @@ EXPORT_SYMBOL(drm_gem_shmem_pin); */ void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem) { + dma_resv_assert_held(shmem->base.resv); + WARN_ON(shmem->base.import_attach); drm_gem_shmem_put_pages(shmem); } EXPORT_SYMBOL(drm_gem_shmem_unpin); -static int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, - struct iosys_map *map) +/* + * drm_gem_shmem_vmap - Create a virtual mapping for a shmem GEM object + * @shmem: shmem GEM object + * @map: Returns the kernel virtual address of the SHMEM GEM object's backing + * store. + * + * This function makes sure that a contiguous kernel virtual address mapping + * exists for the buffer backing the shmem GEM object. It hides the differences + * between dma-buf imported and natively allocated objects. + * + * Acquired mappings should be cleaned up by calling drm_gem_shmem_vunmap(). + * + * Returns: + * 0 on success or a negative error code on failure. + */ +int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, + struct iosys_map *map) { struct drm_gem_object *obj = &shmem->base; int ret = 0; @@ -304,6 +292,8 @@ static int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, } else { pgprot_t prot = PAGE_KERNEL; + dma_resv_assert_held(shmem->base.resv); + if (shmem->vmap_use_count++ > 0) { iosys_map_set_vaddr(map, shmem->vaddr); return 0; @@ -338,45 +328,30 @@ static int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, return ret; } +EXPORT_SYMBOL(drm_gem_shmem_vmap); /* - * drm_gem_shmem_vmap - Create a virtual mapping for a shmem GEM object + * drm_gem_shmem_vunmap - Unmap a virtual mapping for a shmem GEM object * @shmem: shmem GEM object - * @map: Returns the kernel virtual address of the SHMEM GEM object's backing - * store. - * - * This function makes sure that a contiguous kernel virtual address mapping - * exists for the buffer backing the shmem GEM object. It hides the differences - * between dma-buf imported and natively allocated objects. + * @map: Kernel virtual address where the SHMEM GEM object was mapped * - * Acquired mappings should be cleaned up by calling drm_gem_shmem_vunmap(). + * This function cleans up a kernel virtual address mapping acquired by + * drm_gem_shmem_vmap(). The mapping is only removed when the use count drops to + * zero. * - * Returns: - * 0 on success or a negative error code on failure. + * This function hides the differences between dma-buf imported and natively + * allocated objects. */ -int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, - struct iosys_map *map) -{ - int ret; - - ret = mutex_lock_interruptible(&shmem->vmap_lock); - if (ret) - return ret; - ret = drm_gem_shmem_vmap_locked(shmem, map); - mutex_unlock(&shmem->vmap_lock); - - return ret; -} -EXPORT_SYMBOL(drm_gem_shmem_vmap); - -static void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem, - struct iosys_map *map) +void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, + struct iosys_map *map) { struct drm_gem_object *obj = &shmem->base; if (obj->import_attach) { dma_buf_vunmap(obj->import_attach->dmabuf, map); } else { + dma_resv_assert_held(shmem->base.resv); + if (WARN_ON_ONCE(!shmem->vmap_use_count)) return; @@ -389,26 +364,6 @@ static void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem, shmem->vaddr = NULL; } - -/* - * drm_gem_shmem_vunmap - Unmap a virtual mapping for a shmem GEM object - * @shmem: shmem GEM object - * @map: Kernel virtual address where the SHMEM GEM object was mapped - * - * This function cleans up a kernel virtual address mapping acquired by - * drm_gem_shmem_vmap(). The mapping is only removed when the use count drops to - * zero. - * - * This function hides the differences between dma-buf imported and natively - * allocated objects. - */ -void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, - struct iosys_map *map) -{ - mutex_lock(&shmem->vmap_lock); - drm_gem_shmem_vunmap_locked(shmem, map); - mutex_unlock(&shmem->vmap_lock); -} EXPORT_SYMBOL(drm_gem_shmem_vunmap); static struct drm_gem_shmem_object * @@ -441,24 +396,24 @@ drm_gem_shmem_create_with_handle(struct drm_file *file_priv, */ int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv) { - mutex_lock(&shmem->pages_lock); + dma_resv_assert_held(shmem->base.resv); if (shmem->madv >= 0) shmem->madv = madv; madv = shmem->madv; - mutex_unlock(&shmem->pages_lock); - return (madv >= 0); } EXPORT_SYMBOL(drm_gem_shmem_madvise); -void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem) +void drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem) { struct drm_gem_object *obj = &shmem->base; struct drm_device *dev = obj->dev; + dma_resv_assert_held(shmem->base.resv); + WARN_ON(!drm_gem_shmem_is_purgeable(shmem)); dma_unmap_sgtable(dev->dev, shmem->sgt, DMA_BIDIRECTIONAL, 0); @@ -466,7 +421,7 @@ void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem) kfree(shmem->sgt); shmem->sgt = NULL; - drm_gem_shmem_put_pages_locked(shmem); + drm_gem_shmem_put_pages(shmem); shmem->madv = -1; @@ -482,17 +437,6 @@ void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem) invalidate_mapping_pages(file_inode(obj->filp)->i_mapping, 0, (loff_t)-1); } -EXPORT_SYMBOL(drm_gem_shmem_purge_locked); - -bool drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem) -{ - if (!mutex_trylock(&shmem->pages_lock)) - return false; - drm_gem_shmem_purge_locked(shmem); - mutex_unlock(&shmem->pages_lock); - - return true; -} EXPORT_SYMBOL(drm_gem_shmem_purge); /** @@ -548,7 +492,7 @@ static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf) /* We don't use vmf->pgoff since that has the fake offset */ page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT; - mutex_lock(&shmem->pages_lock); + dma_resv_lock(shmem->base.resv, NULL); if (page_offset >= num_pages || WARN_ON_ONCE(!shmem->pages) || @@ -560,7 +504,7 @@ static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf) ret = vmf_insert_pfn(vma, vmf->address, page_to_pfn(page)); } - mutex_unlock(&shmem->pages_lock); + dma_resv_unlock(shmem->base.resv); return ret; } @@ -573,8 +517,10 @@ static void drm_gem_shmem_vm_open(struct vm_area_struct *vma) WARN_ON(shmem->base.import_attach); + dma_resv_lock(shmem->base.resv, NULL); ret = drm_gem_shmem_get_pages(shmem); WARN_ON_ONCE(ret != 0); + dma_resv_unlock(shmem->base.resv); drm_gem_vm_open(vma); } @@ -584,7 +530,10 @@ static void drm_gem_shmem_vm_close(struct vm_area_struct *vma) struct drm_gem_object *obj = vma->vm_private_data; struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); + dma_resv_lock(shmem->base.resv, NULL); drm_gem_shmem_put_pages(shmem); + dma_resv_unlock(shmem->base.resv); + drm_gem_vm_close(vma); } @@ -619,7 +568,10 @@ int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct return dma_buf_mmap(obj->dma_buf, vma, 0); } + dma_resv_lock(shmem->base.resv, NULL); ret = drm_gem_shmem_get_pages(shmem); + dma_resv_unlock(shmem->base.resv); + if (ret) { drm_gem_vm_close(vma); return ret; @@ -707,9 +659,11 @@ struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem) WARN_ON(obj->import_attach); + dma_resv_lock(shmem->base.resv, NULL); + ret = drm_gem_shmem_get_pages(shmem); if (ret) - return ERR_PTR(ret); + goto err_unlock; sgt = drm_gem_shmem_get_sg_table(shmem); if (IS_ERR(sgt)) { @@ -723,6 +677,8 @@ struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem) shmem->sgt = sgt; + dma_resv_unlock(shmem->base.resv); + return sgt; err_free_sgt: @@ -730,6 +686,8 @@ struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem) kfree(sgt); err_put_pages: drm_gem_shmem_put_pages(shmem); +err_unlock: + dma_resv_unlock(shmem->base.resv); return ERR_PTR(ret); } EXPORT_SYMBOL_GPL(drm_gem_shmem_get_pages_sgt); diff --git a/drivers/gpu/drm/lima/lima_gem.c b/drivers/gpu/drm/lima/lima_gem.c index 0f1ca0b0db49..5008f0c2428f 100644 --- a/drivers/gpu/drm/lima/lima_gem.c +++ b/drivers/gpu/drm/lima/lima_gem.c @@ -34,7 +34,7 @@ int lima_heap_alloc(struct lima_bo *bo, struct lima_vm *vm) new_size = min(new_size, bo->base.base.size); - mutex_lock(&bo->base.pages_lock); + dma_resv_lock(bo->base.base.resv, NULL); if (bo->base.pages) { pages = bo->base.pages; @@ -42,7 +42,7 @@ int lima_heap_alloc(struct lima_bo *bo, struct lima_vm *vm) pages = kvmalloc_array(bo->base.base.size >> PAGE_SHIFT, sizeof(*pages), GFP_KERNEL | __GFP_ZERO); if (!pages) { - mutex_unlock(&bo->base.pages_lock); + dma_resv_unlock(bo->base.base.resv); return -ENOMEM; } @@ -56,13 +56,13 @@ int lima_heap_alloc(struct lima_bo *bo, struct lima_vm *vm) struct page *page = shmem_read_mapping_page(mapping, i); if (IS_ERR(page)) { - mutex_unlock(&bo->base.pages_lock); + dma_resv_unlock(bo->base.base.resv); return PTR_ERR(page); } pages[i] = page; } - mutex_unlock(&bo->base.pages_lock); + dma_resv_unlock(bo->base.base.resv); ret = sg_alloc_table_from_pages(&sgt, pages, i, 0, new_size, GFP_KERNEL); diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c index 2fa5afe21288..94b8e6de34b8 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -405,6 +405,10 @@ static int panfrost_ioctl_madvise(struct drm_device *dev, void *data, bo = to_panfrost_bo(gem_obj); + ret = dma_resv_lock_interruptible(bo->base.base.resv, NULL); + if (ret) + goto out_put_object; + mutex_lock(&pfdev->shrinker_lock); mutex_lock(&bo->mappings.lock); if (args->madv == PANFROST_MADV_DONTNEED) { @@ -442,7 +446,8 @@ static int panfrost_ioctl_madvise(struct drm_device *dev, void *data, out_unlock_mappings: mutex_unlock(&bo->mappings.lock); mutex_unlock(&pfdev->shrinker_lock); - + dma_resv_unlock(bo->base.base.resv); +out_put_object: drm_gem_object_put(gem_obj); return ret; } diff --git a/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c b/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c index bf0170782f25..6a71a2555f85 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c +++ b/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c @@ -48,14 +48,14 @@ static bool panfrost_gem_purge(struct drm_gem_object *obj) if (!mutex_trylock(&bo->mappings.lock)) return false; - if (!mutex_trylock(&shmem->pages_lock)) + if (!dma_resv_trylock(shmem->base.resv)) goto unlock_mappings; panfrost_gem_teardown_mappings_locked(bo); - drm_gem_shmem_purge_locked(&bo->base); + drm_gem_shmem_purge(&bo->base); ret = true; - mutex_unlock(&shmem->pages_lock); + dma_resv_unlock(shmem->base.resv); unlock_mappings: mutex_unlock(&bo->mappings.lock); diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index e246d914e7f6..0d5a75b23ed2 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -434,6 +434,7 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, struct panfrost_gem_mapping *bomapping; struct panfrost_gem_object *bo; struct address_space *mapping; + struct drm_gem_object *obj; pgoff_t page_offset; struct sg_table *sgt; struct page **pages; @@ -456,15 +457,16 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, page_offset = addr >> PAGE_SHIFT; page_offset -= bomapping->mmnode.start; - mutex_lock(&bo->base.pages_lock); + obj = &bo->base.base; + + dma_resv_lock(obj->resv, NULL); if (!bo->base.pages) { bo->sgts = kvmalloc_array(bo->base.base.size / SZ_2M, sizeof(struct sg_table), GFP_KERNEL | __GFP_ZERO); if (!bo->sgts) { - mutex_unlock(&bo->base.pages_lock); ret = -ENOMEM; - goto err_bo; + goto err_unlock; } pages = kvmalloc_array(bo->base.base.size >> PAGE_SHIFT, @@ -472,9 +474,8 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, if (!pages) { kvfree(bo->sgts); bo->sgts = NULL; - mutex_unlock(&bo->base.pages_lock); ret = -ENOMEM; - goto err_bo; + goto err_unlock; } bo->base.pages = pages; bo->base.pages_use_count = 1; @@ -482,7 +483,6 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, pages = bo->base.pages; if (pages[page_offset]) { /* Pages are already mapped, bail out. */ - mutex_unlock(&bo->base.pages_lock); goto out; } } @@ -493,14 +493,11 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, for (i = page_offset; i < page_offset + NUM_FAULT_PAGES; i++) { pages[i] = shmem_read_mapping_page(mapping, i); if (IS_ERR(pages[i])) { - mutex_unlock(&bo->base.pages_lock); ret = PTR_ERR(pages[i]); goto err_pages; } } - mutex_unlock(&bo->base.pages_lock); - sgt = &bo->sgts[page_offset / (SZ_2M / PAGE_SIZE)]; ret = sg_alloc_table_from_pages(sgt, pages + page_offset, NUM_FAULT_PAGES, 0, SZ_2M, GFP_KERNEL); @@ -519,6 +516,8 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, dev_dbg(pfdev->dev, "mapped page fault @ AS%d %llx", as, addr); out: + dma_resv_unlock(obj->resv); + panfrost_gem_mapping_put(bomapping); return 0; @@ -527,6 +526,8 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, sg_free_table(sgt); err_pages: drm_gem_shmem_put_pages(&bo->base); +err_unlock: + dma_resv_unlock(obj->resv); err_bo: panfrost_gem_mapping_put(bomapping); return ret; diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index a2201b2488c5..3b055d238584 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -26,11 +26,6 @@ struct drm_gem_shmem_object { */ struct drm_gem_object base; - /** - * @pages_lock: Protects the page table and use count - */ - struct mutex pages_lock; - /** * @pages: Page table */ @@ -79,11 +74,6 @@ struct drm_gem_shmem_object { */ struct sg_table *sgt; - /** - * @vmap_lock: Protects the vmap address and use count - */ - struct mutex vmap_lock; - /** * @vaddr: Kernel virtual address of the backing memory */ @@ -109,7 +99,6 @@ struct drm_gem_shmem_object { struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size); void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem); -int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem); void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem); int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem); void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem); @@ -128,8 +117,7 @@ static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem !shmem->base.dma_buf && !shmem->base.import_attach; } -void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem); -bool drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem); +void drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem); struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem); struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem); -- 2.37.3