Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:

 - a few MM hotfixes

 - kthread, tools, scripts, ntfs and ocfs2

 - some of MM

Subsystems affected by this patch series: kthread, tools, scripts, ntfs,
ocfs2 and mm (hofixes, pagealloc, slab-generic, slab, slub, kcsan,
debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, mincore,
sparsemem, vmalloc, kasan, pagealloc, hugetlb and vmscan).

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits)
  mm: vmscan: consistent update to pgrefill
  mm/vmscan.c: fix typo
  khugepaged: khugepaged_test_exit() check mmget_still_valid()
  khugepaged: retract_page_tables() remember to test exit
  khugepaged: collapse_pte_mapped_thp() protect the pmd lock
  khugepaged: collapse_pte_mapped_thp() flush the right range
  mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possible
  mm: thp: replace HTTP links with HTTPS ones
  mm/page_alloc: fix memalloc_nocma_{save/restore} APIs
  mm/page_alloc.c: skip setting nodemask when we are in interrupt
  mm/page_alloc: fallbacks at most has 3 elements
  mm/page_alloc: silence a KASAN false positive
  mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask()
  mm/page_alloc.c: simplify pageblock bitmap access
  mm/page_alloc.c: extract the common part in pfn_to_bitidx()
  mm/page_alloc.c: replace the definition of NR_MIGRATETYPE_BITS with PB_migratetype_bits
  mm/shuffle: remove dynamic reconfiguration
  mm/memory_hotplug: document why shuffle_zone() is relevant
  mm/page_alloc: remove nr_free_pagecache_pages()
  mm: remove vm_total_pages
  ...

7 files changed, 44 insertions, 65 deletions

diff --git a/arch/arm64/include/asm/pgalloc.h b/arch/arm64/include/asm/pgalloc.h
index 58e93583ddb6..3c6a7f5988b1 100644
--- a/arch/arm64/include/asm/pgalloc.h
+++ b/arch/arm64/include/asm/pgalloc.h
@@ -13,37 +13,13 @@
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 
-#include <asm-generic/pgalloc.h>	/* for pte_{alloc,free}_one */
+#define __HAVE_ARCH_PGD_FREE
+#include <asm-generic/pgalloc.h>
 
 #define PGD_SIZE	(PTRS_PER_PGD * sizeof(pgd_t))
 
 #if CONFIG_PGTABLE_LEVELS > 2
 
-static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
-{
-	gfp_t gfp = GFP_PGTABLE_USER;
-	struct page *page;
-
-	if (mm == &init_mm)
-		gfp = GFP_PGTABLE_KERNEL;
-
-	page = alloc_page(gfp);
-	if (!page)
-		return NULL;
-	if (!pgtable_pmd_page_ctor(page)) {
-		__free_page(page);
-		return NULL;
-	}
-	return page_address(page);
-}
-
-static inline void pmd_free(struct mm_struct *mm, pmd_t *pmdp)
-{
-	BUG_ON((unsigned long)pmdp & (PAGE_SIZE-1));
-	pgtable_pmd_page_dtor(virt_to_page(pmdp));
-	free_page((unsigned long)pmdp);
-}
-
 static inline void __pud_populate(pud_t *pudp, phys_addr_t pmdp, pudval_t prot)
 {
 	set_pud(pudp, __pud(__phys_to_pud_val(pmdp) | prot));
@@ -62,17 +38,6 @@ static inline void __pud_populate(pud_t *pudp, phys_addr_t pmdp, pudval_t prot)
 
 #if CONFIG_PGTABLE_LEVELS > 3
 
-static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
-{
-	return (pud_t *)__get_free_page(GFP_PGTABLE_USER);
-}
-
-static inline void pud_free(struct mm_struct *mm, pud_t *pudp)
-{
-	BUG_ON((unsigned long)pudp & (PAGE_SIZE-1));
-	free_page((unsigned long)pudp);
-}
-
 static inline void __p4d_populate(p4d_t *p4dp, phys_addr_t pudp, p4dval_t prot)
 {
 	set_p4d(p4dp, __p4d(__phys_to_p4d_val(pudp) | prot));
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index c793276ec7ad..87e81d29e6fb 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -276,7 +276,7 @@ arch_initcall(reserve_memblock_reserved_regions);
 
 u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
 
-void __init setup_arch(char **cmdline_p)
+void __init __no_sanitize_address setup_arch(char **cmdline_p)
 {
 	init_mm.start_code = (unsigned long) _text;
 	init_mm.end_code   = (unsigned long) _etext;
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index e43a8ff19f0f..8059d50bc8cb 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -43,7 +43,6 @@
 #include <asm/kvm_mmu.h>
 #include <asm/mmu_context.h>
 #include <asm/numa.h>
-#include <asm/pgalloc.h>
 #include <asm/processor.h>
 #include <asm/smp_plat.h>
 #include <asm/sections.h>
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index aa421bf4956e..55ecf6de9ff7 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -17,7 +17,6 @@
 #include <asm/mman.h>
 #include <asm/tlb.h>
 #include <asm/tlbflush.h>
-#include <asm/pgalloc.h>
 
 /*
  * HugeTLB Support Matrix
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index f8c19c6c8e71..481d22c32a2e 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -430,11 +430,9 @@ void __init bootmem_init(void)
 #endif
 
 	/*
-	 * Sparsemem tries to allocate bootmem in memory_present(), so must be
-	 * done after the fixed reservations.
+	 * sparse_init() tries to allocate memory from memblock, so must be
+	 * done after the fixed reservations
 	 */
-	memblocks_present();
-
 	sparse_init();
 	zone_sizes_init(min, max);
 
diff --git a/arch/arm64/mm/ioremap.c b/arch/arm64/mm/ioremap.c
index 9be71bee902c..b5e83c46b23e 100644
--- a/arch/arm64/mm/ioremap.c
+++ b/arch/arm64/mm/ioremap.c
@@ -16,7 +16,6 @@
 
 #include <asm/fixmap.h>
 #include <asm/tlbflush.h>
-#include <asm/pgalloc.h>
 
 static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
 				      pgprot_t prot, void *caller)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 1df25f26571d..75df62fea1b6 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -35,6 +35,7 @@
 #include <asm/mmu_context.h>
 #include <asm/ptdump.h>
 #include <asm/tlbflush.h>
+#include <asm/pgalloc.h>
 
 #define NO_BLOCK_MAPPINGS	BIT(0)
 #define NO_CONT_MAPPINGS	BIT(1)
@@ -760,15 +761,20 @@ int kern_addr_valid(unsigned long addr)
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
-static void free_hotplug_page_range(struct page *page, size_t size)
+static void free_hotplug_page_range(struct page *page, size_t size,
+				    struct vmem_altmap *altmap)
 {
-	WARN_ON(PageReserved(page));
-	free_pages((unsigned long)page_address(page), get_order(size));
+	if (altmap) {
+		vmem_altmap_free(altmap, size >> PAGE_SHIFT);
+	} else {
+		WARN_ON(PageReserved(page));
+		free_pages((unsigned long)page_address(page), get_order(size));
+	}
 }
 
 static void free_hotplug_pgtable_page(struct page *page)
 {
-	free_hotplug_page_range(page, PAGE_SIZE);
+	free_hotplug_page_range(page, PAGE_SIZE, NULL);
 }
 
 static bool pgtable_range_aligned(unsigned long start, unsigned long end,
@@ -791,7 +797,8 @@ static bool pgtable_range_aligned(unsigned long start, unsigned long end,
 }
 
 static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr,
-				    unsigned long end, bool free_mapped)
+				    unsigned long end, bool free_mapped,
+				    struct vmem_altmap *altmap)
 {
 	pte_t *ptep, pte;
 
@@ -805,12 +812,14 @@ static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr,
 		pte_clear(&init_mm, addr, ptep);
 		flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
 		if (free_mapped)
-			free_hotplug_page_range(pte_page(pte), PAGE_SIZE);
+			free_hotplug_page_range(pte_page(pte),
+						PAGE_SIZE, altmap);
 	} while (addr += PAGE_SIZE, addr < end);
 }
 
 static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr,
-				    unsigned long end, bool free_mapped)
+				    unsigned long end, bool free_mapped,
+				    struct vmem_altmap *altmap)
 {
 	unsigned long next;
 	pmd_t *pmdp, pmd;
@@ -833,16 +842,17 @@ static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr,
 			flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
 			if (free_mapped)
 				free_hotplug_page_range(pmd_page(pmd),
-							PMD_SIZE);
+							PMD_SIZE, altmap);
 			continue;
 		}
 		WARN_ON(!pmd_table(pmd));
-		unmap_hotplug_pte_range(pmdp, addr, next, free_mapped);
+		unmap_hotplug_pte_range(pmdp, addr, next, free_mapped, altmap);
 	} while (addr = next, addr < end);
 }
 
 static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr,
-				    unsigned long end, bool free_mapped)
+				    unsigned long end, bool free_mapped,
+				    struct vmem_altmap *altmap)
 {
 	unsigned long next;
 	pud_t *pudp, pud;
@@ -865,16 +875,17 @@ static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr,
 			flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
 			if (free_mapped)
 				free_hotplug_page_range(pud_page(pud),
-							PUD_SIZE);
+							PUD_SIZE, altmap);
 			continue;
 		}
 		WARN_ON(!pud_table(pud));
-		unmap_hotplug_pmd_range(pudp, addr, next, free_mapped);
+		unmap_hotplug_pmd_range(pudp, addr, next, free_mapped, altmap);
 	} while (addr = next, addr < end);
 }
 
 static void unmap_hotplug_p4d_range(pgd_t *pgdp, unsigned long addr,
-				    unsigned long end, bool free_mapped)
+				    unsigned long end, bool free_mapped,
+				    struct vmem_altmap *altmap)
 {
 	unsigned long next;
 	p4d_t *p4dp, p4d;
@@ -887,16 +898,24 @@ static void unmap_hotplug_p4d_range(pgd_t *pgdp, unsigned long addr,
 			continue;
 
 		WARN_ON(!p4d_present(p4d));
-		unmap_hotplug_pud_range(p4dp, addr, next, free_mapped);
+		unmap_hotplug_pud_range(p4dp, addr, next, free_mapped, altmap);
 	} while (addr = next, addr < end);
 }
 
 static void unmap_hotplug_range(unsigned long addr, unsigned long end,
-				bool free_mapped)
+				bool free_mapped, struct vmem_altmap *altmap)
 {
 	unsigned long next;
 	pgd_t *pgdp, pgd;
 
+	/*
+	 * altmap can only be used as vmemmap mapping backing memory.
+	 * In case the backing memory itself is not being freed, then
+	 * altmap is irrelevant. Warn about this inconsistency when
+	 * encountered.
+	 */
+	WARN_ON(!free_mapped && altmap);
+
 	do {
 		next = pgd_addr_end(addr, end);
 		pgdp = pgd_offset_k(addr);
@@ -905,7 +924,7 @@ static void unmap_hotplug_range(unsigned long addr, unsigned long end,
 			continue;
 
 		WARN_ON(!pgd_present(pgd));
-		unmap_hotplug_p4d_range(pgdp, addr, next, free_mapped);
+		unmap_hotplug_p4d_range(pgdp, addr, next, free_mapped, altmap);
 	} while (addr = next, addr < end);
 }
 
@@ -1069,7 +1088,7 @@ static void free_empty_tables(unsigned long addr, unsigned long end,
 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 		struct vmem_altmap *altmap)
 {
-	return vmemmap_populate_basepages(start, end, node);
+	return vmemmap_populate_basepages(start, end, node, altmap);
 }
 #else	/* !ARM64_SWAPPER_USES_SECTION_MAPS */
 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
@@ -1101,7 +1120,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 		if (pmd_none(READ_ONCE(*pmdp))) {
 			void *p = NULL;
 
-			p = vmemmap_alloc_block_buf(PMD_SIZE, node);
+			p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
 			if (!p)
 				return -ENOMEM;
 
@@ -1119,7 +1138,7 @@ void vmemmap_free(unsigned long start, unsigned long end,
 #ifdef CONFIG_MEMORY_HOTPLUG
 	WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END));
 
-	unmap_hotplug_range(start, end, true);
+	unmap_hotplug_range(start, end, true, altmap);
 	free_empty_tables(start, end, VMEMMAP_START, VMEMMAP_END);
 #endif
 }
@@ -1410,7 +1429,7 @@ static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size)
 	WARN_ON(pgdir != init_mm.pgd);
 	WARN_ON((start < PAGE_OFFSET) || (end > PAGE_END));
 
-	unmap_hotplug_range(start, end, false);
+	unmap_hotplug_range(start, end, false, NULL);
 	free_empty_tables(start, end, PAGE_OFFSET, PAGE_END);
 }