Merge tag 'dma-mapping-6.5-2023-06-28' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

- swiotlb cleanups (Petr Tesarik)

- use kvmalloc_array (gaoxu)

- a small step towards removing is_swiotlb_active (Christoph Hellwig)

- fix a Kconfig typo Sui Jingfeng)

* tag 'dma-mapping-6.5-2023-06-28' of git://git.infradead.org/users/hch/dma-mapping:
drm/nouveau: stop using is_swiotlb_active
swiotlb: use the atomic counter of total used slabs if available
swiotlb: remove unused field "used" from struct io_tlb_mem
dma-remap: use kvmalloc_array/kvfree for larger dma memory remap
dma-mapping: fix a Kconfig typo

drivers/gpu/drm/nouveau/nouveau_ttm.c

···
  */
 
 #include <linux/limits.h>
-#include <linux/swiotlb.h>
 
 #include <drm/ttm/ttm_range_manager.h>
+#include <drm/drm_cache.h>
 
 #include "nouveau_drv.h"
 #include "nouveau_gem.h"
···
 	struct nvkm_pci *pci = device->pci;
 	struct nvif_mmu *mmu = &drm->client.mmu;
 	struct drm_device *dev = drm->dev;
-	bool need_swiotlb = false;
 	int typei, ret;
 
 	ret = nouveau_ttm_init_host(drm, 0);
···
 		drm->agp.cma = pci->agp.cma;
 	}
 
-#if IS_ENABLED(CONFIG_SWIOTLB) && IS_ENABLED(CONFIG_X86)
-	need_swiotlb = is_swiotlb_active(dev->dev);
-#endif
-
 	ret = ttm_device_init(&drm->ttm.bdev, &nouveau_bo_driver, drm->dev->dev,
 				  dev->anon_inode->i_mapping,
-				  dev->vma_offset_manager, need_swiotlb,
+				  dev->vma_offset_manager,
+				  drm_need_swiotlb(drm->client.mmu.dmabits),
 				  drm->client.mmu.dmabits <= 32);
 	if (ret) {
 		NV_ERROR(drm, "error initialising bo driver, %d\n", ret);

include/linux/swiotlb.h

···
  * @nslabs:	The number of IO TLB blocks (in groups of 64) between @start and
  *		@end. For default swiotlb, this is command line adjustable via
  *		setup_io_tlb_npages.
- * @used:	The number of used IO TLB block.
  * @list:	The free list describing the number of free entries available
  *		from each index.
  * @orig_addr:	The original address corresponding to a mapped entry.
···
 	phys_addr_t end;
 	void *vaddr;
 	unsigned long nslabs;
-	unsigned long used;
 	struct dentry *debugfs;
 	bool late_alloc;
 	bool force_bounce;

kernel/dma/Kconfig

···
 #
 # Select this option if the architecture needs special handling for
 # DMA_ATTR_WRITE_COMBINE.  Normally the "uncached" mapping should be what
-# people thing of when saying write combine, so very few platforms should
+# people think of when saying write combine, so very few platforms should
 # need to enable this.
 #
 config ARCH_HAS_DMA_WRITE_COMBINE

kernel/dma/remap.c

···
 	void *vaddr;
 	int i;
 
-	pages = kmalloc_array(count, sizeof(struct page *), GFP_KERNEL);
+	pages = kvmalloc_array(count, sizeof(struct page *), GFP_KERNEL);
 	if (!pages)
 		return NULL;
 	for (i = 0; i < count; i++)
 		pages[i] = nth_page(page, i);
 	vaddr = vmap(pages, count, VM_DMA_COHERENT, prot);
-	kfree(pages);
+	kvfree(pages);
 
 	return vaddr;
 }

kernel/dma/swiotlb.c

···
 	return -1;
 }
 
+#ifdef CONFIG_DEBUG_FS
+
+static unsigned long mem_used(struct io_tlb_mem *mem)
+{
+	return atomic_long_read(&mem->total_used);
+}
+
+#else /* !CONFIG_DEBUG_FS */
+
 static unsigned long mem_used(struct io_tlb_mem *mem)
 {
 	int i;
···
 		used += mem->areas[i].used;
 	return used;
 }
+
+#endif /* CONFIG_DEBUG_FS */
 
 phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
 		size_t mapping_size, size_t alloc_size,