Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton:
 "A few little subsystems and a start of a lot of MM patches.

  Subsystems affected by this patch series: squashfs, ocfs2, parisc,
  vfs. With mm subsystems: slab-generic, slub, debug, pagecache, gup,
  swap, memcg, pagemap, memory-failure, vmalloc, kasan"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (128 commits)
  kasan: move kasan_report() into report.c
  mm/mm_init.c: report kasan-tag information stored in page->flags
  ubsan: entirely disable alignment checks under UBSAN_TRAP
  kasan: fix clang compilation warning due to stack protector
  x86/mm: remove vmalloc faulting
  mm: remove vmalloc_sync_(un)mappings()
  x86/mm/32: implement arch_sync_kernel_mappings()
  x86/mm/64: implement arch_sync_kernel_mappings()
  mm/ioremap: track which page-table levels were modified
  mm/vmalloc: track which page-table levels were modified
  mm: add functions to track page directory modifications
  s390: use __vmalloc_node in stack_alloc
  powerpc: use __vmalloc_node in alloc_vm_stack
  arm64: use __vmalloc_node in arch_alloc_vmap_stack
  mm: remove vmalloc_user_node_flags
  mm: switch the test_vmalloc module to use __vmalloc_node
  mm: remove __vmalloc_node_flags_caller
  mm: remove both instances of __vmalloc_node_flags
  mm: remove the prot argument to __vmalloc_node
  mm: remove the pgprot argument to __vmalloc
  ...

1 files changed, 18 insertions, 46 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 39e45b8a5031..e12eb32d9e17 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3076,22 +3076,16 @@ static int submit_extent_page(unsigned int opf,
 static void attach_extent_buffer_page(struct extent_buffer *eb,
 				      struct page *page)
 {
-	if (!PagePrivate(page)) {
-		SetPagePrivate(page);
-		get_page(page);
-		set_page_private(page, (unsigned long)eb);
-	} else {
+	if (!PagePrivate(page))
+		attach_page_private(page, eb);
+	else
 		WARN_ON(page->private != (unsigned long)eb);
-	}
 }
 
 void set_page_extent_mapped(struct page *page)
 {
-	if (!PagePrivate(page)) {
-		SetPagePrivate(page);
-		get_page(page);
-		set_page_private(page, EXTENT_PAGE_PRIVATE);
-	}
+	if (!PagePrivate(page))
+		attach_page_private(page, (void *)EXTENT_PAGE_PRIVATE);
 }
 
 static struct extent_map *
@@ -4367,51 +4361,32 @@ int extent_writepages(struct address_space *mapping,
 	return ret;
 }
 
-int extent_readpages(struct address_space *mapping, struct list_head *pages,
-		     unsigned nr_pages)
+void extent_readahead(struct readahead_control *rac)
 {
 	struct bio *bio = NULL;
 	unsigned long bio_flags = 0;
 	struct page *pagepool[16];
 	struct extent_map *em_cached = NULL;
-	int nr = 0;
 	u64 prev_em_start = (u64)-1;
+	int nr;
 
-	while (!list_empty(pages)) {
-		u64 contig_end = 0;
-
-		for (nr = 0; nr < ARRAY_SIZE(pagepool) && !list_empty(pages);) {
-			struct page *page = lru_to_page(pages);
-
-			prefetchw(&page->flags);
-			list_del(&page->lru);
-			if (add_to_page_cache_lru(page, mapping, page->index,
-						readahead_gfp_mask(mapping))) {
-				put_page(page);
-				break;
-			}
-
-			pagepool[nr++] = page;
-			contig_end = page_offset(page) + PAGE_SIZE - 1;
-		}
+	while ((nr = readahead_page_batch(rac, pagepool))) {
+		u64 contig_start = page_offset(pagepool[0]);
+		u64 contig_end = page_offset(pagepool[nr - 1]) + PAGE_SIZE - 1;
 
-		if (nr) {
-			u64 contig_start = page_offset(pagepool[0]);
+		ASSERT(contig_start + nr * PAGE_SIZE - 1 == contig_end);
 
-			ASSERT(contig_start + nr * PAGE_SIZE - 1 == contig_end);
-
-			contiguous_readpages(pagepool, nr, contig_start,
-				     contig_end, &em_cached, &bio, &bio_flags,
-				     &prev_em_start);
-		}
+		contiguous_readpages(pagepool, nr, contig_start, contig_end,
+				&em_cached, &bio, &bio_flags, &prev_em_start);
 	}
 
 	if (em_cached)
 		free_extent_map(em_cached);
 
-	if (bio)
-		return submit_one_bio(bio, 0, bio_flags);
-	return 0;
+	if (bio) {
+		if (submit_one_bio(bio, 0, bio_flags))
+			return;
+	}
 }
 
 /*
@@ -4929,10 +4904,7 @@ static void btrfs_release_extent_buffer_pages(struct extent_buffer *eb)
 			 * We need to make sure we haven't be attached
 			 * to a new eb.
 			 */
-			ClearPagePrivate(page);
-			set_page_private(page, 0);
-			/* One for the page private */
-			put_page(page);
+			detach_page_private(page);
 		}
 
 		if (mapped)