1 files changed, 296 insertions, 138 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index c82290b9c1fc..2024bbd573d2 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -544,7 +544,7 @@ static struct page *dequeue_huge_page_node(struct hstate *h, int nid)
 /* Movability of hugepages depends on migration support. */
 static inline gfp_t htlb_alloc_mask(struct hstate *h)
 {
-	if (hugepages_treat_as_movable || hugepage_migration_support(h))
+	if (hugepages_treat_as_movable || hugepage_migration_supported(h))
 		return GFP_HIGHUSER_MOVABLE;
 	else
 		return GFP_HIGHUSER;
@@ -607,25 +607,242 @@ err:
 	return NULL;
 }
 
+/*
+ * common helper functions for hstate_next_node_to_{alloc|free}.
+ * We may have allocated or freed a huge page based on a different
+ * nodes_allowed previously, so h->next_node_to_{alloc|free} might
+ * be outside of *nodes_allowed.  Ensure that we use an allowed
+ * node for alloc or free.
+ */
+static int next_node_allowed(int nid, nodemask_t *nodes_allowed)
+{
+	nid = next_node(nid, *nodes_allowed);
+	if (nid == MAX_NUMNODES)
+		nid = first_node(*nodes_allowed);
+	VM_BUG_ON(nid >= MAX_NUMNODES);
+
+	return nid;
+}
+
+static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed)
+{
+	if (!node_isset(nid, *nodes_allowed))
+		nid = next_node_allowed(nid, nodes_allowed);
+	return nid;
+}
+
+/*
+ * returns the previously saved node ["this node"] from which to
+ * allocate a persistent huge page for the pool and advance the
+ * next node from which to allocate, handling wrap at end of node
+ * mask.
+ */
+static int hstate_next_node_to_alloc(struct hstate *h,
+					nodemask_t *nodes_allowed)
+{
+	int nid;
+
+	VM_BUG_ON(!nodes_allowed);
+
+	nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed);
+	h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed);
+
+	return nid;
+}
+
+/*
+ * helper for free_pool_huge_page() - return the previously saved
+ * node ["this node"] from which to free a huge page.  Advance the
+ * next node id whether or not we find a free huge page to free so
+ * that the next attempt to free addresses the next node.
+ */
+static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed)
+{
+	int nid;
+
+	VM_BUG_ON(!nodes_allowed);
+
+	nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed);
+	h->next_nid_to_free = next_node_allowed(nid, nodes_allowed);
+
+	return nid;
+}
+
+#define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask)		\
+	for (nr_nodes = nodes_weight(*mask);				\
+		nr_nodes > 0 &&						\
+		((node = hstate_next_node_to_alloc(hs, mask)) || 1);	\
+		nr_nodes--)
+
+#define for_each_node_mask_to_free(hs, nr_nodes, node, mask)		\
+	for (nr_nodes = nodes_weight(*mask);				\
+		nr_nodes > 0 &&						\
+		((node = hstate_next_node_to_free(hs, mask)) || 1);	\
+		nr_nodes--)
+
+#if defined(CONFIG_CMA) && defined(CONFIG_X86_64)
+static void destroy_compound_gigantic_page(struct page *page,
+					unsigned long order)
+{
+	int i;
+	int nr_pages = 1 << order;
+	struct page *p = page + 1;
+
+	for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) {
+		__ClearPageTail(p);
+		set_page_refcounted(p);
+		p->first_page = NULL;
+	}
+
+	set_compound_order(page, 0);
+	__ClearPageHead(page);
+}
+
+static void free_gigantic_page(struct page *page, unsigned order)
+{
+	free_contig_range(page_to_pfn(page), 1 << order);
+}
+
+static int __alloc_gigantic_page(unsigned long start_pfn,
+				unsigned long nr_pages)
+{
+	unsigned long end_pfn = start_pfn + nr_pages;
+	return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
+}
+
+static bool pfn_range_valid_gigantic(unsigned long start_pfn,
+				unsigned long nr_pages)
+{
+	unsigned long i, end_pfn = start_pfn + nr_pages;
+	struct page *page;
+
+	for (i = start_pfn; i < end_pfn; i++) {
+		if (!pfn_valid(i))
+			return false;
+
+		page = pfn_to_page(i);
+
+		if (PageReserved(page))
+			return false;
+
+		if (page_count(page) > 0)
+			return false;
+
+		if (PageHuge(page))
+			return false;
+	}
+
+	return true;
+}
+
+static bool zone_spans_last_pfn(const struct zone *zone,
+			unsigned long start_pfn, unsigned long nr_pages)
+{
+	unsigned long last_pfn = start_pfn + nr_pages - 1;
+	return zone_spans_pfn(zone, last_pfn);
+}
+
+static struct page *alloc_gigantic_page(int nid, unsigned order)
+{
+	unsigned long nr_pages = 1 << order;
+	unsigned long ret, pfn, flags;
+	struct zone *z;
+
+	z = NODE_DATA(nid)->node_zones;
+	for (; z - NODE_DATA(nid)->node_zones < MAX_NR_ZONES; z++) {
+		spin_lock_irqsave(&z->lock, flags);
+
+		pfn = ALIGN(z->zone_start_pfn, nr_pages);
+		while (zone_spans_last_pfn(z, pfn, nr_pages)) {
+			if (pfn_range_valid_gigantic(pfn, nr_pages)) {
+				/*
+				 * We release the zone lock here because
+				 * alloc_contig_range() will also lock the zone
+				 * at some point. If there's an allocation
+				 * spinning on this lock, it may win the race
+				 * and cause alloc_contig_range() to fail...
+				 */
+				spin_unlock_irqrestore(&z->lock, flags);
+				ret = __alloc_gigantic_page(pfn, nr_pages);
+				if (!ret)
+					return pfn_to_page(pfn);
+				spin_lock_irqsave(&z->lock, flags);
+			}
+			pfn += nr_pages;
+		}
+
+		spin_unlock_irqrestore(&z->lock, flags);
+	}
+
+	return NULL;
+}
+
+static void prep_new_huge_page(struct hstate *h, struct page *page, int nid);
+static void prep_compound_gigantic_page(struct page *page, unsigned long order);
+
+static struct page *alloc_fresh_gigantic_page_node(struct hstate *h, int nid)
+{
+	struct page *page;
+
+	page = alloc_gigantic_page(nid, huge_page_order(h));
+	if (page) {
+		prep_compound_gigantic_page(page, huge_page_order(h));
+		prep_new_huge_page(h, page, nid);
+	}
+
+	return page;
+}
+
+static int alloc_fresh_gigantic_page(struct hstate *h,
+				nodemask_t *nodes_allowed)
+{
+	struct page *page = NULL;
+	int nr_nodes, node;
+
+	for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) {
+		page = alloc_fresh_gigantic_page_node(h, node);
+		if (page)
+			return 1;
+	}
+
+	return 0;
+}
+
+static inline bool gigantic_page_supported(void) { return true; }
+#else
+static inline bool gigantic_page_supported(void) { return false; }
+static inline void free_gigantic_page(struct page *page, unsigned order) { }
+static inline void destroy_compound_gigantic_page(struct page *page,
+						unsigned long order) { }
+static inline int alloc_fresh_gigantic_page(struct hstate *h,
+					nodemask_t *nodes_allowed) { return 0; }
+#endif
+
 static void update_and_free_page(struct hstate *h, struct page *page)
 {
 	int i;
 
-	VM_BUG_ON(h->order >= MAX_ORDER);
+	if (hstate_is_gigantic(h) && !gigantic_page_supported())
+		return;
 
 	h->nr_huge_pages--;
 	h->nr_huge_pages_node[page_to_nid(page)]--;
 	for (i = 0; i < pages_per_huge_page(h); i++) {
 		page[i].flags &= ~(1 << PG_locked | 1 << PG_error |
 				1 << PG_referenced | 1 << PG_dirty |
-				1 << PG_active | 1 << PG_reserved |
-				1 << PG_private | 1 << PG_writeback);
+				1 << PG_active | 1 << PG_private |
+				1 << PG_writeback);
 	}
 	VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page), page);
 	set_compound_page_dtor(page, NULL);
 	set_page_refcounted(page);
-	arch_release_hugepage(page);
-	__free_pages(page, huge_page_order(h));
+	if (hstate_is_gigantic(h)) {
+		destroy_compound_gigantic_page(page, huge_page_order(h));
+		free_gigantic_page(page, huge_page_order(h));
+	} else {
+		arch_release_hugepage(page);
+		__free_pages(page, huge_page_order(h));
+	}
 }
 
 struct hstate *size_to_hstate(unsigned long size)
@@ -664,7 +881,7 @@ static void free_huge_page(struct page *page)
 	if (restore_reserve)
 		h->resv_huge_pages++;
 
-	if (h->surplus_huge_pages_node[nid] && huge_page_order(h) < MAX_ORDER) {
+	if (h->surplus_huge_pages_node[nid]) {
 		/* remove the page from active list */
 		list_del(&page->lru);
 		update_and_free_page(h, page);
@@ -690,8 +907,7 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
 	put_page(page); /* free it into the hugepage allocator */
 }
 
-static void __init prep_compound_gigantic_page(struct page *page,
-					       unsigned long order)
+static void prep_compound_gigantic_page(struct page *page, unsigned long order)
 {
 	int i;
 	int nr_pages = 1 << order;
@@ -769,9 +985,6 @@ static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid)
 {
 	struct page *page;
 
-	if (h->order >= MAX_ORDER)
-		return NULL;
-
 	page = alloc_pages_exact_node(nid,
 		htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE|
 						__GFP_REPEAT|__GFP_NOWARN,
@@ -787,79 +1000,6 @@ static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid)
 	return page;
 }
 
-/*
- * common helper functions for hstate_next_node_to_{alloc|free}.
- * We may have allocated or freed a huge page based on a different
- * nodes_allowed previously, so h->next_node_to_{alloc|free} might
- * be outside of *nodes_allowed.  Ensure that we use an allowed
- * node for alloc or free.
- */
-static int next_node_allowed(int nid, nodemask_t *nodes_allowed)
-{
-	nid = next_node(nid, *nodes_allowed);
-	if (nid == MAX_NUMNODES)
-		nid = first_node(*nodes_allowed);
-	VM_BUG_ON(nid >= MAX_NUMNODES);
-
-	return nid;
-}
-
-static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed)
-{
-	if (!node_isset(nid, *nodes_allowed))
-		nid = next_node_allowed(nid, nodes_allowed);
-	return nid;
-}
-
-/*
- * returns the previously saved node ["this node"] from which to
- * allocate a persistent huge page for the pool and advance the
- * next node from which to allocate, handling wrap at end of node
- * mask.
- */
-static int hstate_next_node_to_alloc(struct hstate *h,
-					nodemask_t *nodes_allowed)
-{
-	int nid;
-
-	VM_BUG_ON(!nodes_allowed);
-
-	nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed);
-	h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed);
-
-	return nid;
-}
-
-/*
- * helper for free_pool_huge_page() - return the previously saved
- * node ["this node"] from which to free a huge page.  Advance the
- * next node id whether or not we find a free huge page to free so
- * that the next attempt to free addresses the next node.
- */
-static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed)
-{
-	int nid;
-
-	VM_BUG_ON(!nodes_allowed);
-
-	nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed);
-	h->next_nid_to_free = next_node_allowed(nid, nodes_allowed);
-
-	return nid;
-}
-
-#define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask)		\
-	for (nr_nodes = nodes_weight(*mask);				\
-		nr_nodes > 0 &&						\
-		((node = hstate_next_node_to_alloc(hs, mask)) || 1);	\
-		nr_nodes--)
-
-#define for_each_node_mask_to_free(hs, nr_nodes, node, mask)		\
-	for (nr_nodes = nodes_weight(*mask);				\
-		nr_nodes > 0 &&						\
-		((node = hstate_next_node_to_free(hs, mask)) || 1);	\
-		nr_nodes--)
-
 static int alloc_fresh_huge_page(struct hstate *h, nodemask_t *nodes_allowed)
 {
 	struct page *page;
@@ -963,7 +1103,7 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
 	struct page *page;
 	unsigned int r_nid;
 
-	if (h->order >= MAX_ORDER)
+	if (hstate_is_gigantic(h))
 		return NULL;
 
 	/*
@@ -1156,7 +1296,7 @@ static void return_unused_surplus_pages(struct hstate *h,
 	h->resv_huge_pages -= unused_resv_pages;
 
 	/* Cannot return gigantic pages currently */
-	if (h->order >= MAX_ORDER)
+	if (hstate_is_gigantic(h))
 		return;
 
 	nr_pages = min(unused_resv_pages, h->surplus_huge_pages);
@@ -1246,24 +1386,17 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma,
 			return ERR_PTR(-ENOSPC);
 
 	ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg);
-	if (ret) {
-		if (chg || avoid_reserve)
-			hugepage_subpool_put_pages(spool, 1);
-		return ERR_PTR(-ENOSPC);
-	}
+	if (ret)
+		goto out_subpool_put;
+
 	spin_lock(&hugetlb_lock);
 	page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, chg);
 	if (!page) {
 		spin_unlock(&hugetlb_lock);
 		page = alloc_buddy_huge_page(h, NUMA_NO_NODE);
-		if (!page) {
-			hugetlb_cgroup_uncharge_cgroup(idx,
-						       pages_per_huge_page(h),
-						       h_cg);
-			if (chg || avoid_reserve)
-				hugepage_subpool_put_pages(spool, 1);
-			return ERR_PTR(-ENOSPC);
-		}
+		if (!page)
+			goto out_uncharge_cgroup;
+
 		spin_lock(&hugetlb_lock);
 		list_move(&page->lru, &h->hugepage_activelist);
 		/* Fall through */
@@ -1275,6 +1408,13 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma,
 
 	vma_commit_reservation(h, vma, addr);
 	return page;
+
+out_uncharge_cgroup:
+	hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg);
+out_subpool_put:
+	if (chg || avoid_reserve)
+		hugepage_subpool_put_pages(spool, 1);
+	return ERR_PTR(-ENOSPC);
 }
 
 /*
@@ -1356,7 +1496,7 @@ static void __init gather_bootmem_prealloc(void)
 		 * fix confusing memory reports from free(1) and another
 		 * side-effects, like CommitLimit going negative.
 		 */
-		if (h->order > (MAX_ORDER - 1))
+		if (hstate_is_gigantic(h))
 			adjust_managed_page_count(page, 1 << h->order);
 	}
 }
@@ -1366,7 +1506,7 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
 	unsigned long i;
 
 	for (i = 0; i < h->max_huge_pages; ++i) {
-		if (h->order >= MAX_ORDER) {
+		if (hstate_is_gigantic(h)) {
 			if (!alloc_bootmem_huge_page(h))
 				break;
 		} else if (!alloc_fresh_huge_page(h,
@@ -1382,7 +1522,7 @@ static void __init hugetlb_init_hstates(void)
 
 	for_each_hstate(h) {
 		/* oversize hugepages were init'ed in early boot */
-		if (h->order < MAX_ORDER)
+		if (!hstate_is_gigantic(h))
 			hugetlb_hstate_alloc_pages(h);
 	}
 }
@@ -1416,7 +1556,7 @@ static void try_to_free_low(struct hstate *h, unsigned long count,
 {
 	int i;
 
-	if (h->order >= MAX_ORDER)
+	if (hstate_is_gigantic(h))
 		return;
 
 	for_each_node_mask(i, *nodes_allowed) {
@@ -1479,7 +1619,7 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 {
 	unsigned long min_count, ret;
 
-	if (h->order >= MAX_ORDER)
+	if (hstate_is_gigantic(h) && !gigantic_page_supported())
 		return h->max_huge_pages;
 
 	/*
@@ -1506,7 +1646,10 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 		 * and reducing the surplus.
 		 */
 		spin_unlock(&hugetlb_lock);
-		ret = alloc_fresh_huge_page(h, nodes_allowed);
+		if (hstate_is_gigantic(h))
+			ret = alloc_fresh_gigantic_page(h, nodes_allowed);
+		else
+			ret = alloc_fresh_huge_page(h, nodes_allowed);
 		spin_lock(&hugetlb_lock);
 		if (!ret)
 			goto out;
@@ -1606,7 +1749,7 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy,
 		goto out;
 
 	h = kobj_to_hstate(kobj, &nid);
-	if (h->order >= MAX_ORDER) {
+	if (hstate_is_gigantic(h) && !gigantic_page_supported()) {
 		err = -EINVAL;
 		goto out;
 	}
@@ -1689,7 +1832,7 @@ static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj,
 	unsigned long input;
 	struct hstate *h = kobj_to_hstate(kobj, NULL);
 
-	if (h->order >= MAX_ORDER)
+	if (hstate_is_gigantic(h))
 		return -EINVAL;
 
 	err = kstrtoul(buf, 10, &input);
@@ -2113,7 +2256,7 @@ static int hugetlb_sysctl_handler_common(bool obey_mempolicy,
 
 	tmp = h->max_huge_pages;
 
-	if (write && h->order >= MAX_ORDER)
+	if (write && hstate_is_gigantic(h) && !gigantic_page_supported())
 		return -EINVAL;
 
 	table->data = &tmp;
@@ -2169,7 +2312,7 @@ int hugetlb_overcommit_handler(struct ctl_table *table, int write,
 
 	tmp = h->nr_overcommit_huge_pages;
 
-	if (write && h->order >= MAX_ORDER)
+	if (write && hstate_is_gigantic(h))
 		return -EINVAL;
 
 	table->data = &tmp;
@@ -2377,6 +2520,31 @@ static void set_huge_ptep_writable(struct vm_area_struct *vma,
 		update_mmu_cache(vma, address, ptep);
 }
 
+static int is_hugetlb_entry_migration(pte_t pte)
+{
+	swp_entry_t swp;
+
+	if (huge_pte_none(pte) || pte_present(pte))
+		return 0;
+	swp = pte_to_swp_entry(pte);
+	if (non_swap_entry(swp) && is_migration_entry(swp))
+		return 1;
+	else
+		return 0;
+}
+
+static int is_hugetlb_entry_hwpoisoned(pte_t pte)
+{
+	swp_entry_t swp;
+
+	if (huge_pte_none(pte) || pte_present(pte))
+		return 0;
+	swp = pte_to_swp_entry(pte);
+	if (non_swap_entry(swp) && is_hwpoison_entry(swp))
+		return 1;
+	else
+		return 0;
+}
 
 int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
 			    struct vm_area_struct *vma)
@@ -2416,10 +2584,26 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
 		dst_ptl = huge_pte_lock(h, dst, dst_pte);
 		src_ptl = huge_pte_lockptr(h, src, src_pte);
 		spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
-		if (!huge_pte_none(huge_ptep_get(src_pte))) {
+		entry = huge_ptep_get(src_pte);
+		if (huge_pte_none(entry)) { /* skip none entry */
+			;
+		} else if (unlikely(is_hugetlb_entry_migration(entry) ||
+				    is_hugetlb_entry_hwpoisoned(entry))) {
+			swp_entry_t swp_entry = pte_to_swp_entry(entry);
+
+			if (is_write_migration_entry(swp_entry) && cow) {
+				/*
+				 * COW mappings require pages in both
+				 * parent and child to be set to read.
+				 */
+				make_migration_entry_read(&swp_entry);
+				entry = swp_entry_to_pte(swp_entry);
+				set_huge_pte_at(src, addr, src_pte, entry);
+			}
+			set_huge_pte_at(dst, addr, dst_pte, entry);
+		} else {
 			if (cow)
 				huge_ptep_set_wrprotect(src, addr, src_pte);
-			entry = huge_ptep_get(src_pte);
 			ptepage = pte_page(entry);
 			get_page(ptepage);
 			page_dup_rmap(ptepage);
@@ -2435,32 +2619,6 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
 	return ret;
 }
 
-static int is_hugetlb_entry_migration(pte_t pte)
-{
-	swp_entry_t swp;
-
-	if (huge_pte_none(pte) || pte_present(pte))
-		return 0;
-	swp = pte_to_swp_entry(pte);
-	if (non_swap_entry(swp) && is_migration_entry(swp))
-		return 1;
-	else
-		return 0;
-}
-
-static int is_hugetlb_entry_hwpoisoned(pte_t pte)
-{
-	swp_entry_t swp;
-
-	if (huge_pte_none(pte) || pte_present(pte))
-		return 0;
-	swp = pte_to_swp_entry(pte);
-	if (non_swap_entry(swp) && is_hwpoison_entry(swp))
-		return 1;
-	else
-		return 0;
-}
-
 void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
 			    unsigned long start, unsigned long end,
 			    struct page *ref_page)