Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "9 patches.

  Subsystems affected by this patch series: mm (thp, memcg, gup,
  migration, memory-hotplug), lib, and x86"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: don't rely on system state to detect hot-plug operations
  mm: replace memmap_context by meminit_context
  arch/x86/lib/usercopy_64.c: fix __copy_user_flushcache() cache writeback
  lib/memregion.c: include memregion.h
  lib/string.c: implement stpcpy
  mm/migrate: correct thp migration stats
  mm/gup: fix gup_fast with dynamic page table folding
  mm: memcontrol: fix missing suffix of workingset_restore
  mm, THP, swap: fix allocating cluster for swapfile by mistake

Documentation/admin-guide/cgroup-v2.rst

@@ -1324,15 +1324,26 @@ PAGE_SIZE multiple when read back.
 	  pgmajfault
 		Number of major page faults incurred
 
-	  workingset_refault
+	  workingset_refault_anon
-		Number of refaults of previously evicted pages
+		Number of refaults of previously evicted anonymous pages.
 
-	  workingset_activate
+	  workingset_refault_file
-		Number of refaulted pages that were immediately activated
+		Number of refaults of previously evicted file pages.
 
-	  workingset_restore
+	  workingset_activate_anon
-		Number of restored pages which have been detected as an active
+		Number of refaulted anonymous pages that were immediately
-		workingset before they got reclaimed.
+		activated.
+
+	  workingset_activate_file
+		Number of refaulted file pages that were immediately activated.
+
+	  workingset_restore_anon
+		Number of restored anonymous pages which have been detected as
+		an active workingset before they got reclaimed.
+
+	  workingset_restore_file
+		Number of restored file pages which have been detected as an
+		active workingset before they got reclaimed.
 
 	  workingset_nodereclaim
 		Number of times a shadow node has been reclaimed

arch/ia64/mm/init.c

@@ -538,7 +538,7 @@ virtual_memmap_init(u64 start, u64 end, void *arg)
 	if (map_start < map_end)
 		memmap_init_zone((unsigned long)(map_end - map_start),
 				 args->nid, args->zone, page_to_pfn(map_start),
-				 MEMMAP_EARLY, NULL);
+				 MEMINIT_EARLY, NULL);
 	return 0;
 }
 
@@ -547,8 +547,8 @@ memmap_init (unsigned long size, int nid, unsigned long zone,
 	     unsigned long start_pfn)
 {
 	if (!vmem_map) {
-		memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY,
+		memmap_init_zone(size, nid, zone, start_pfn,
-				NULL);
+				 MEMINIT_EARLY, NULL);
 	} else {
 		struct page *start;
 		struct memmap_init_callback_data args;

arch/s390/include/asm/pgtable.h

@@ -1260,26 +1260,44 @@ static inline pgd_t *pgd_offset_raw(pgd_t *pgd, unsigned long address)
 
 #define pgd_offset(mm, address) pgd_offset_raw(READ_ONCE((mm)->pgd), address)
 
-static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
+static inline p4d_t *p4d_offset_lockless(pgd_t *pgdp, pgd_t pgd, unsigned long address)
 {
-	if ((pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) >= _REGION_ENTRY_TYPE_R1)
+	if ((pgd_val(pgd) & _REGION_ENTRY_TYPE_MASK) >= _REGION_ENTRY_TYPE_R1)
-		return (p4d_t *) pgd_deref(*pgd) + p4d_index(address);
+		return (p4d_t *) pgd_deref(pgd) + p4d_index(address);
-	return (p4d_t *) pgd;
+	return (p4d_t *) pgdp;
+}
+#define p4d_offset_lockless p4d_offset_lockless
+
+static inline p4d_t *p4d_offset(pgd_t *pgdp, unsigned long address)
+{
+	return p4d_offset_lockless(pgdp, *pgdp, address);
 }
 
-static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
+static inline pud_t *pud_offset_lockless(p4d_t *p4dp, p4d_t p4d, unsigned long address)
 {
-	if ((p4d_val(*p4d) & _REGION_ENTRY_TYPE_MASK) >= _REGION_ENTRY_TYPE_R2)
+	if ((p4d_val(p4d) & _REGION_ENTRY_TYPE_MASK) >= _REGION_ENTRY_TYPE_R2)
-		return (pud_t *) p4d_deref(*p4d) + pud_index(address);
+		return (pud_t *) p4d_deref(p4d) + pud_index(address);
-	return (pud_t *) p4d;
+	return (pud_t *) p4dp;
+}
+#define pud_offset_lockless pud_offset_lockless
+
+static inline pud_t *pud_offset(p4d_t *p4dp, unsigned long address)
+{
+	return pud_offset_lockless(p4dp, *p4dp, address);
 }
 #define pud_offset pud_offset
 
-static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
+static inline pmd_t *pmd_offset_lockless(pud_t *pudp, pud_t pud, unsigned long address)
 {
-	if ((pud_val(*pud) & _REGION_ENTRY_TYPE_MASK) >= _REGION_ENTRY_TYPE_R3)
+	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) >= _REGION_ENTRY_TYPE_R3)
-		return (pmd_t *) pud_deref(*pud) + pmd_index(address);
+		return (pmd_t *) pud_deref(pud) + pmd_index(address);
-	return (pmd_t *) pud;
+	return (pmd_t *) pudp;
+}
+#define pmd_offset_lockless pmd_offset_lockless
+
+static inline pmd_t *pmd_offset(pud_t *pudp, unsigned long address)
+{
+	return pmd_offset_lockless(pudp, *pudp, address);
 }
 #define pmd_offset pmd_offset
 

arch/x86/lib/usercopy_64.c

@@ -120,7 +120,7 @@ long __copy_user_flushcache(void *dst, const void __user *src, unsigned size)
 	 */
 	if (size < 8) {
 		if (!IS_ALIGNED(dest, 4) || size != 4)
-			clean_cache_range(dst, 1);
+			clean_cache_range(dst, size);
 	} else {
 		if (!IS_ALIGNED(dest, 8)) {
 			dest = ALIGN(dest, boot_cpu_data.x86_clflush_size);

drivers/base/node.c

@@ -761,41 +761,10 @@ static int __ref get_nid_for_pfn(unsigned long pfn)
 	return pfn_to_nid(pfn);
 }
 
-/* register memory section under specified node if it spans that node */
+static int do_register_memory_block_under_node(int nid,
-static int register_mem_sect_under_node(struct memory_block *mem_blk,
+					       struct memory_block *mem_blk)
-					 void *arg)
 {
-	unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE;
+	int ret;
-	unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
-	unsigned long end_pfn = start_pfn + memory_block_pfns - 1;
-	int ret, nid = *(int *)arg;
-	unsigned long pfn;
-
-	for (pfn = start_pfn; pfn <= end_pfn; pfn++) {
-		int page_nid;
-
-		/*
-		 * memory block could have several absent sections from start.
-		 * skip pfn range from absent section
-		 */
-		if (!pfn_in_present_section(pfn)) {
-			pfn = round_down(pfn + PAGES_PER_SECTION,
-					 PAGES_PER_SECTION) - 1;
-			continue;
-		}
-
-		/*
-		 * We need to check if page belongs to nid only for the boot
-		 * case, during hotplug we know that all pages in the memory
-		 * block belong to the same node.
-		 */
-		if (system_state == SYSTEM_BOOTING) {
-			page_nid = get_nid_for_pfn(pfn);
-			if (page_nid < 0)
-				continue;
-			if (page_nid != nid)
-				continue;
-		}
 
 	/*
 	 * If this memory block spans multiple nodes, we only indicate
@@ -813,10 +782,58 @@ static int register_mem_sect_under_node(struct memory_block *mem_blk,
 				&node_devices[nid]->dev.kobj,
 				kobject_name(&node_devices[nid]->dev.kobj));
 }
+
+/* register memory section under specified node if it spans that node */
+static int register_mem_block_under_node_early(struct memory_block *mem_blk,
+					       void *arg)
+{
+	unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE;
+	unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
+	unsigned long end_pfn = start_pfn + memory_block_pfns - 1;
+	int nid = *(int *)arg;
+	unsigned long pfn;
+
+	for (pfn = start_pfn; pfn <= end_pfn; pfn++) {
+		int page_nid;
+
+		/*
+		 * memory block could have several absent sections from start.
+		 * skip pfn range from absent section
+		 */
+		if (!pfn_in_present_section(pfn)) {
+			pfn = round_down(pfn + PAGES_PER_SECTION,
+					 PAGES_PER_SECTION) - 1;
+			continue;
+		}
+
+		/*
+		 * We need to check if page belongs to nid only at the boot
+		 * case because node's ranges can be interleaved.
+		 */
+		page_nid = get_nid_for_pfn(pfn);
+		if (page_nid < 0)
+			continue;
+		if (page_nid != nid)
+			continue;
+
+		return do_register_memory_block_under_node(nid, mem_blk);
+	}
 	/* mem section does not span the specified node */
 	return 0;
 }
 
+/*
+ * During hotplug we know that all pages in the memory block belong to the same
+ * node.
+ */
+static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk,
+						 void *arg)
+{
+	int nid = *(int *)arg;
+
+	return do_register_memory_block_under_node(nid, mem_blk);
+}
+
 /*
  * Unregister a memory block device under the node it spans. Memory blocks
  * with multiple nodes cannot be offlined and therefore also never be removed.
@@ -832,11 +849,19 @@ void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
 			  kobject_name(&node_devices[mem_blk->nid]->dev.kobj));
 }
 
-int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn)
+int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn,
+		      enum meminit_context context)
 {
+	walk_memory_blocks_func_t func;
+
+	if (context == MEMINIT_HOTPLUG)
+		func = register_mem_block_under_node_hotplug;
+	else
+		func = register_mem_block_under_node_early;
+
 	return walk_memory_blocks(PFN_PHYS(start_pfn),
 				  PFN_PHYS(end_pfn - start_pfn), (void *)&nid,
-				  register_mem_sect_under_node);
+				  func);
 }
 
 #ifdef CONFIG_HUGETLBFS

include/linux/mm.h

@@ -2416,7 +2416,7 @@ extern int __meminit __early_pfn_to_nid(unsigned long pfn,
 
 extern void set_dma_reserve(unsigned long new_dma_reserve);
 extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long,
-		enum memmap_context, struct vmem_altmap *);
+		enum meminit_context, struct vmem_altmap *);
 extern void setup_per_zone_wmarks(void);
 extern int __meminit init_per_zone_wmark_min(void);
 extern void mem_init(void);

include/linux/mmzone.h

@@ -824,10 +824,15 @@ bool zone_watermark_ok(struct zone *z, unsigned int order,
 		unsigned int alloc_flags);
 bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
 		unsigned long mark, int highest_zoneidx);
-enum memmap_context {
+/*
-	MEMMAP_EARLY,
+ * Memory initialization context, use to differentiate memory added by
-	MEMMAP_HOTPLUG,
+ * the platform statically or via memory hotplug interface.
+ */
+enum meminit_context {
+	MEMINIT_EARLY,
+	MEMINIT_HOTPLUG,
 };
+
 extern void init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
 				     unsigned long size);
 

include/linux/node.h

@@ -99,11 +99,13 @@ extern struct node *node_devices[];
 typedef  void (*node_registration_func_t)(struct node *);
 
 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA)
-extern int link_mem_sections(int nid, unsigned long start_pfn,
+int link_mem_sections(int nid, unsigned long start_pfn,
-			     unsigned long end_pfn);
+		      unsigned long end_pfn,
+		      enum meminit_context context);
 #else
 static inline int link_mem_sections(int nid, unsigned long start_pfn,
-				    unsigned long end_pfn)
+				    unsigned long end_pfn,
+				    enum meminit_context context)
 {
 	return 0;
 }
@@ -128,7 +130,8 @@ static inline int register_one_node(int nid)
 		if (error)
 			return error;
 		/* link memory sections under this node */
-		error = link_mem_sections(nid, start_pfn, end_pfn);
+		error = link_mem_sections(nid, start_pfn, end_pfn,
+					  MEMINIT_EARLY);
 	}
 
 	return error;

include/linux/pgtable.h

@@ -1427,6 +1427,16 @@ typedef unsigned int pgtbl_mod_mask;
 #define mm_pmd_folded(mm)	__is_defined(__PAGETABLE_PMD_FOLDED)
 #endif
 
+#ifndef p4d_offset_lockless
+#define p4d_offset_lockless(pgdp, pgd, address) p4d_offset(&(pgd), address)
+#endif
+#ifndef pud_offset_lockless
+#define pud_offset_lockless(p4dp, p4d, address) pud_offset(&(p4d), address)
+#endif
+#ifndef pmd_offset_lockless
+#define pmd_offset_lockless(pudp, pud, address) pmd_offset(&(pud), address)
+#endif
+
 /*
  * p?d_leaf() - true if this entry is a final mapping to a physical address.
  * This differs from p?d_huge() by the fact that they are always available (if

lib/memregion.c

@@ -2,6 +2,7 @@
 /* identifiers for device / performance-differentiated memory regions */
 #include <linux/idr.h>
 #include <linux/types.h>
+#include <linux/memregion.h>
 
 static DEFINE_IDA(memregion_ids);
 

lib/string.c

@@ -272,6 +272,30 @@ ssize_t strscpy_pad(char *dest, const char *src, size_t count)
 }
 EXPORT_SYMBOL(strscpy_pad);
 
+/**
+ * stpcpy - copy a string from src to dest returning a pointer to the new end
+ *          of dest, including src's %NUL-terminator. May overrun dest.
+ * @dest: pointer to end of string being copied into. Must be large enough
+ *        to receive copy.
+ * @src: pointer to the beginning of string being copied from. Must not overlap
+ *       dest.
+ *
+ * stpcpy differs from strcpy in a key way: the return value is a pointer
+ * to the new %NUL-terminating character in @dest. (For strcpy, the return
+ * value is a pointer to the start of @dest). This interface is considered
+ * unsafe as it doesn't perform bounds checking of the inputs. As such it's
+ * not recommended for usage. Instead, its definition is provided in case
+ * the compiler lowers other libcalls to stpcpy.
+ */
+char *stpcpy(char *__restrict__ dest, const char *__restrict__ src);
+char *stpcpy(char *__restrict__ dest, const char *__restrict__ src)
+{
+	while ((*dest++ = *src++) != '\0')
+		/* nothing */;
+	return --dest;
+}
+EXPORT_SYMBOL(stpcpy);
+
 #ifndef __HAVE_ARCH_STRCAT
 /**
  * strcat - Append one %NUL-terminated string to another

mm/gup.c

@@ -2485,13 +2485,13 @@ static int gup_huge_pgd(pgd_t orig, pgd_t *pgdp, unsigned long addr,
 	return 1;
 }
 
-static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
+static int gup_pmd_range(pud_t *pudp, pud_t pud, unsigned long addr, unsigned long end,
 		unsigned int flags, struct page **pages, int *nr)
 {
 	unsigned long next;
 	pmd_t *pmdp;
 
-	pmdp = pmd_offset(&pud, addr);
+	pmdp = pmd_offset_lockless(pudp, pud, addr);
 	do {
 		pmd_t pmd = READ_ONCE(*pmdp);
 
@@ -2528,13 +2528,13 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end,
 	return 1;
 }
 
-static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end,
+static int gup_pud_range(p4d_t *p4dp, p4d_t p4d, unsigned long addr, unsigned long end,
 			 unsigned int flags, struct page **pages, int *nr)
 {
 	unsigned long next;
 	pud_t *pudp;
 
-	pudp = pud_offset(&p4d, addr);
+	pudp = pud_offset_lockless(p4dp, p4d, addr);
 	do {
 		pud_t pud = READ_ONCE(*pudp);
 
@@ -2549,20 +2549,20 @@ static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end,
 			if (!gup_huge_pd(__hugepd(pud_val(pud)), addr,
 					 PUD_SHIFT, next, flags, pages, nr))
 				return 0;
-		} else if (!gup_pmd_range(pud, addr, next, flags, pages, nr))
+		} else if (!gup_pmd_range(pudp, pud, addr, next, flags, pages, nr))
 			return 0;
 	} while (pudp++, addr = next, addr != end);
 
 	return 1;
 }
 
-static int gup_p4d_range(pgd_t pgd, unsigned long addr, unsigned long end,
+static int gup_p4d_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr, unsigned long end,
 			 unsigned int flags, struct page **pages, int *nr)
 {
 	unsigned long next;
 	p4d_t *p4dp;
 
-	p4dp = p4d_offset(&pgd, addr);
+	p4dp = p4d_offset_lockless(pgdp, pgd, addr);
 	do {
 		p4d_t p4d = READ_ONCE(*p4dp);
 
@@ -2574,7 +2574,7 @@ static int gup_p4d_range(pgd_t pgd, unsigned long addr, unsigned long end,
 			if (!gup_huge_pd(__hugepd(p4d_val(p4d)), addr,
 					 P4D_SHIFT, next, flags, pages, nr))
 				return 0;
-		} else if (!gup_pud_range(p4d, addr, next, flags, pages, nr))
+		} else if (!gup_pud_range(p4dp, p4d, addr, next, flags, pages, nr))
 			return 0;
 	} while (p4dp++, addr = next, addr != end);
 
@@ -2602,7 +2602,7 @@ static void gup_pgd_range(unsigned long addr, unsigned long end,
 			if (!gup_huge_pd(__hugepd(pgd_val(pgd)), addr,
 					 PGDIR_SHIFT, next, flags, pages, nr))
 				return;
-		} else if (!gup_p4d_range(pgd, addr, next, flags, pages, nr))
+		} else if (!gup_p4d_range(pgdp, pgd, addr, next, flags, pages, nr))
 			return;
 	} while (pgdp++, addr = next, addr != end);
 }

mm/memcontrol.c

@@ -1538,9 +1538,9 @@ static char *memory_stat_format(struct mem_cgroup *memcg)
 		       memcg_page_state(memcg, WORKINGSET_ACTIVATE_ANON));
 	seq_buf_printf(&s, "workingset_activate_file %lu\n",
 		       memcg_page_state(memcg, WORKINGSET_ACTIVATE_FILE));
-	seq_buf_printf(&s, "workingset_restore %lu\n",
+	seq_buf_printf(&s, "workingset_restore_anon %lu\n",
 		       memcg_page_state(memcg, WORKINGSET_RESTORE_ANON));
-	seq_buf_printf(&s, "workingset_restore %lu\n",
+	seq_buf_printf(&s, "workingset_restore_file %lu\n",
 		       memcg_page_state(memcg, WORKINGSET_RESTORE_FILE));
 	seq_buf_printf(&s, "workingset_nodereclaim %lu\n",
 		       memcg_page_state(memcg, WORKINGSET_NODERECLAIM));

mm/memory_hotplug.c

@@ -729,7 +729,7 @@ void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
 	 * are reserved so nobody should be touching them so we should be safe
 	 */
 	memmap_init_zone(nr_pages, nid, zone_idx(zone), start_pfn,
-			MEMMAP_HOTPLUG, altmap);
+			 MEMINIT_HOTPLUG, altmap);
 
 	set_zone_contiguous(zone);
 }
@@ -1080,7 +1080,8 @@ int __ref add_memory_resource(int nid, struct resource *res)
 	}
 
 	/* link memory sections under this node.*/
-	ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1));
+	ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1),
+				MEMINIT_HOTPLUG);
 	BUG_ON(ret);
 
 	/* create new memmap entry */

mm/migrate.c

@@ -1446,7 +1446,7 @@ retry:
 			 * Capture required information that might get lost
 			 * during migration.
 			 */
-			is_thp = PageTransHuge(page);
+			is_thp = PageTransHuge(page) && !PageHuge(page);
 			nr_subpages = thp_nr_pages(page);
 			cond_resched();
 
@@ -1472,7 +1472,7 @@ retry:
 				 * we encounter them after the rest of the list
 				 * is processed.
 				 */
-				if (PageTransHuge(page) && !PageHuge(page)) {
+				if (is_thp) {
 					lock_page(page);
 					rc = split_huge_page_to_list(page, from);
 					unlock_page(page);
@@ -1481,8 +1481,7 @@ retry:
 						nr_thp_split++;
 						goto retry;
 					}
-				}
+
-				if (is_thp) {
 					nr_thp_failed++;
 					nr_failed += nr_subpages;
 					goto out;

mm/page_alloc.c

@@ -5975,7 +5975,7 @@ overlap_memmap_init(unsigned long zone, unsigned long *pfn)
  * done. Non-atomic initialization, single-pass.
  */
 void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
-		unsigned long start_pfn, enum memmap_context context,
+		unsigned long start_pfn, enum meminit_context context,
 		struct vmem_altmap *altmap)
 {
 	unsigned long pfn, end_pfn = start_pfn + size;
@@ -6007,7 +6007,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 		 * There can be holes in boot-time mem_map[]s handed to this
 		 * function.  They do not exist on hotplugged memory.
 		 */
-		if (context == MEMMAP_EARLY) {
+		if (context == MEMINIT_EARLY) {
 			if (overlap_memmap_init(zone, &pfn))
 				continue;
 			if (defer_init(nid, pfn, end_pfn))
@@ -6016,7 +6016,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 
 		page = pfn_to_page(pfn);
 		__init_single_page(page, pfn, zone, nid);
-		if (context == MEMMAP_HOTPLUG)
+		if (context == MEMINIT_HOTPLUG)
 			__SetPageReserved(page);
 
 		/*
@@ -6099,7 +6099,7 @@ void __ref memmap_init_zone_device(struct zone *zone,
 		 * check here not to call set_pageblock_migratetype() against
 		 * pfn out of zone.
 		 *
-		 * Please note that MEMMAP_HOTPLUG path doesn't clear memmap
+		 * Please note that MEMINIT_HOTPLUG path doesn't clear memmap
 		 * because this is done early in section_activate()
 		 */
 		if (!(pfn & (pageblock_nr_pages - 1))) {
@@ -6137,7 +6137,7 @@ void __meminit __weak memmap_init(unsigned long size, int nid,
 		if (end_pfn > start_pfn) {
 			size = end_pfn - start_pfn;
 			memmap_init_zone(size, nid, zone, start_pfn,
-					 MEMMAP_EARLY, NULL);
+					 MEMINIT_EARLY, NULL);
 		}
 	}
 }

mm/swapfile.c

@@ -1078,7 +1078,7 @@ start_over:
 			goto nextsi;
 		}
 		if (size == SWAPFILE_CLUSTER) {
-			if (!(si->flags & SWP_FS))
+			if (si->flags & SWP_BLKDEV)
 				n_ret = swap_alloc_cluster(si, swp_entries);
 		} else
 			n_ret = scan_swap_map_slots(si, SWAP_HAS_CACHE,