Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:
 "A few misc subsystems and some of MM.

  175 patches.

  Subsystems affected by this patch series: ia64, kbuild, scripts, sh,
  ocfs2, kfifo, vfs, kernel/watchdog, and mm (slab-generic, slub,
  kmemleak, debug, pagecache, msync, gup, memremap, memcg, pagemap,
  mremap, dma, sparsemem, vmalloc, documentation, kasan, initialization,
  pagealloc, and memory-failure)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (175 commits)
  mm/memory-failure: unnecessary amount of unmapping
  mm/mmzone.h: fix existing kernel-doc comments and link them to core-api
  mm: page_alloc: ignore init_on_free=1 for debug_pagealloc=1
  net: page_pool: use alloc_pages_bulk in refill code path
  net: page_pool: refactor dma_map into own function page_pool_dma_map
  SUNRPC: refresh rq_pages using a bulk page allocator
  SUNRPC: set rq_page_end differently
  mm/page_alloc: inline __rmqueue_pcplist
  mm/page_alloc: optimize code layout for __alloc_pages_bulk
  mm/page_alloc: add an array-based interface to the bulk page allocator
  mm/page_alloc: add a bulk page allocator
  mm/page_alloc: rename alloced to allocated
  mm/page_alloc: duplicate include linux/vmalloc.h
  mm, page_alloc: avoid page_to_pfn() in move_freepages()
  mm/Kconfig: remove default DISCONTIGMEM_MANUAL
  mm: page_alloc: dump migrate-failed pages
  mm/mempolicy: fix mpol_misplaced kernel-doc
  mm/mempolicy: rewrite alloc_pages_vma documentation
  mm/mempolicy: rewrite alloc_pages documentation
  mm/mempolicy: rename alloc_pages_current to alloc_pages
  ...

4 files changed, 28 insertions, 102 deletions

diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig
index 369695df8b15..69f57ca9c68d 100644
--- a/drivers/gpu/drm/i915/Kconfig
+++ b/drivers/gpu/drm/i915/Kconfig
@@ -20,6 +20,7 @@ config DRM_I915
 	select INPUT if ACPI
 	select ACPI_VIDEO if ACPI
 	select ACPI_BUTTON if ACPI
+	select IO_MAPPING
 	select SYNC_FILE
 	select IOSF_MBI
 	select CRC32
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index 2561a2f1e54f..23f6b00e08e2 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -367,11 +367,10 @@ retry:
 		goto err_unpin;
 
 	/* Finally, remap it using the new GTT offset */
-	ret = remap_io_mapping(area,
-			       area->vm_start + (vma->ggtt_view.partial.offset << PAGE_SHIFT),
-			       (ggtt->gmadr.start + vma->node.start) >> PAGE_SHIFT,
-			       min_t(u64, vma->size, area->vm_end - area->vm_start),
-			       &ggtt->iomap);
+	ret = io_mapping_map_user(&ggtt->iomap, area, area->vm_start +
+			(vma->ggtt_view.partial.offset << PAGE_SHIFT),
+			(ggtt->gmadr.start + vma->node.start) >> PAGE_SHIFT,
+			min_t(u64, vma->size, area->vm_end - area->vm_start));
 	if (ret)
 		goto err_fence;
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 69e43bf91a15..9ec9277539ec 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1905,9 +1905,6 @@ int i915_reg_read_ioctl(struct drm_device *dev, void *data,
 			struct drm_file *file);
 
 /* i915_mm.c */
-int remap_io_mapping(struct vm_area_struct *vma,
-		     unsigned long addr, unsigned long pfn, unsigned long size,
-		     struct io_mapping *iomap);
 int remap_io_sg(struct vm_area_struct *vma,
 		unsigned long addr, unsigned long size,
 		struct scatterlist *sgl, resource_size_t iobase);
diff --git a/drivers/gpu/drm/i915/i915_mm.c b/drivers/gpu/drm/i915/i915_mm.c
index 666808cb3a32..4c8cd08c672d 100644
--- a/drivers/gpu/drm/i915/i915_mm.c
+++ b/drivers/gpu/drm/i915/i915_mm.c
@@ -28,89 +28,9 @@
 
 #include "i915_drv.h"
 
-struct remap_pfn {
-	struct mm_struct *mm;
-	unsigned long pfn;
-	pgprot_t prot;
-
-	struct sgt_iter sgt;
-	resource_size_t iobase;
-};
-
-static int remap_pfn(pte_t *pte, unsigned long addr, void *data)
-{
-	struct remap_pfn *r = data;
-
-	/* Special PTE are not associated with any struct page */
-	set_pte_at(r->mm, addr, pte, pte_mkspecial(pfn_pte(r->pfn, r->prot)));
-	r->pfn++;
-
-	return 0;
-}
-
-#define use_dma(io) ((io) != -1)
-
-static inline unsigned long sgt_pfn(const struct remap_pfn *r)
-{
-	if (use_dma(r->iobase))
-		return (r->sgt.dma + r->sgt.curr + r->iobase) >> PAGE_SHIFT;
-	else
-		return r->sgt.pfn + (r->sgt.curr >> PAGE_SHIFT);
-}
-
-static int remap_sg(pte_t *pte, unsigned long addr, void *data)
-{
-	struct remap_pfn *r = data;
-
-	if (GEM_WARN_ON(!r->sgt.sgp))
-		return -EINVAL;
-
-	/* Special PTE are not associated with any struct page */
-	set_pte_at(r->mm, addr, pte,
-		   pte_mkspecial(pfn_pte(sgt_pfn(r), r->prot)));
-	r->pfn++; /* track insertions in case we need to unwind later */
-
-	r->sgt.curr += PAGE_SIZE;
-	if (r->sgt.curr >= r->sgt.max)
-		r->sgt = __sgt_iter(__sg_next(r->sgt.sgp), use_dma(r->iobase));
-
-	return 0;
-}
-
-/**
- * remap_io_mapping - remap an IO mapping to userspace
- * @vma: user vma to map to
- * @addr: target user address to start at
- * @pfn: physical address of kernel memory
- * @size: size of map area
- * @iomap: the source io_mapping
- *
- *  Note: this is only safe if the mm semaphore is held when called.
- */
-int remap_io_mapping(struct vm_area_struct *vma,
-		     unsigned long addr, unsigned long pfn, unsigned long size,
-		     struct io_mapping *iomap)
-{
-	struct remap_pfn r;
-	int err;
-
 #define EXPECTED_FLAGS (VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP)
-	GEM_BUG_ON((vma->vm_flags & EXPECTED_FLAGS) != EXPECTED_FLAGS);
-
-	/* We rely on prevalidation of the io-mapping to skip track_pfn(). */
-	r.mm = vma->vm_mm;
-	r.pfn = pfn;
-	r.prot = __pgprot((pgprot_val(iomap->prot) & _PAGE_CACHE_MASK) |
-			  (pgprot_val(vma->vm_page_prot) & ~_PAGE_CACHE_MASK));
 
-	err = apply_to_page_range(r.mm, addr, size, remap_pfn, &r);
-	if (unlikely(err)) {
-		zap_vma_ptes(vma, addr, (r.pfn - pfn) << PAGE_SHIFT);
-		return err;
-	}
-
-	return 0;
-}
+#define use_dma(io) ((io) != -1)
 
 /**
  * remap_io_sg - remap an IO mapping to userspace
@@ -126,12 +46,7 @@ int remap_io_sg(struct vm_area_struct *vma,
 		unsigned long addr, unsigned long size,
 		struct scatterlist *sgl, resource_size_t iobase)
 {
-	struct remap_pfn r = {
-		.mm = vma->vm_mm,
-		.prot = vma->vm_page_prot,
-		.sgt = __sgt_iter(sgl, use_dma(iobase)),
-		.iobase = iobase,
-	};
+	unsigned long pfn, len, remapped = 0;
 	int err;
 
 	/* We rely on prevalidation of the io-mapping to skip track_pfn(). */
@@ -140,11 +55,25 @@ int remap_io_sg(struct vm_area_struct *vma,
 	if (!use_dma(iobase))
 		flush_cache_range(vma, addr, size);
 
-	err = apply_to_page_range(r.mm, addr, size, remap_sg, &r);
-	if (unlikely(err)) {
-		zap_vma_ptes(vma, addr, r.pfn << PAGE_SHIFT);
-		return err;
-	}
-
-	return 0;
+	do {
+		if (use_dma(iobase)) {
+			if (!sg_dma_len(sgl))
+				break;
+			pfn = (sg_dma_address(sgl) + iobase) >> PAGE_SHIFT;
+			len = sg_dma_len(sgl);
+		} else {
+			pfn = page_to_pfn(sg_page(sgl));
+			len = sgl->length;
+		}
+
+		err = remap_pfn_range(vma, addr + remapped, pfn, len,
+				      vma->vm_page_prot);
+		if (err)
+			break;
+		remapped += len;
+	} while ((sgl = __sg_next(sgl)));
+
+	if (err)
+		zap_vma_ptes(vma, addr, remapped);
+	return err;
 }