1 files changed, 18 insertions, 160 deletions

diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 7e73e8c69096..58f7f2bd535d 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * IA-32 Huge TLB Page Support for Kernel.
  *
@@ -7,180 +8,37 @@
 #include <linux/init.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
+#include <linux/sched/mm.h>
 #include <linux/hugetlb.h>
 #include <linux/pagemap.h>
 #include <linux/err.h>
 #include <linux/sysctl.h>
+#include <linux/compat.h>
 #include <asm/mman.h>
 #include <asm/tlb.h>
 #include <asm/tlbflush.h>
-#include <asm/pgalloc.h>
+#include <asm/elf.h>
 
-#if 0	/* This is just for testing */
-struct page *
-follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
-{
-	unsigned long start = address;
-	int length = 1;
-	int nr;
-	struct page *page;
-	struct vm_area_struct *vma;
-
-	vma = find_vma(mm, addr);
-	if (!vma || !is_vm_hugetlb_page(vma))
-		return ERR_PTR(-EINVAL);
-
-	pte = huge_pte_offset(mm, address);
-
-	/* hugetlb should be locked, and hence, prefaulted */
-	WARN_ON(!pte || pte_none(*pte));
-
-	page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)];
-
-	WARN_ON(!PageHead(page));
-
-	return page;
-}
-
-int pmd_huge(pmd_t pmd)
-{
-	return 0;
-}
-
-int pud_huge(pud_t pud)
-{
-	return 0;
-}
-
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
-		pmd_t *pmd, int write)
-{
-	return NULL;
-}
-
-#else
-
-struct page *
-follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
-{
-	return ERR_PTR(-EINVAL);
-}
-
-int pmd_huge(pmd_t pmd)
-{
-	return !!(pmd_val(pmd) & _PAGE_PSE);
-}
-
-int pud_huge(pud_t pud)
-{
-	return !!(pud_val(pud) & _PAGE_PSE);
-}
-
-#endif
-
-/* x86_64 also uses this file */
-
-#ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
-static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
-		unsigned long addr, unsigned long len,
-		unsigned long pgoff, unsigned long flags)
-{
-	struct hstate *h = hstate_file(file);
-	struct vm_unmapped_area_info info;
-
-	info.flags = 0;
-	info.length = len;
-	info.low_limit = TASK_UNMAPPED_BASE;
-	info.high_limit = TASK_SIZE;
-	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
-	info.align_offset = 0;
-	return vm_unmapped_area(&info);
-}
-
-static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,
-		unsigned long addr0, unsigned long len,
-		unsigned long pgoff, unsigned long flags)
-{
-	struct hstate *h = hstate_file(file);
-	struct vm_unmapped_area_info info;
-	unsigned long addr;
 
-	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
-	info.length = len;
-	info.low_limit = PAGE_SIZE;
-	info.high_limit = current->mm->mmap_base;
-	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
-	info.align_offset = 0;
-	addr = vm_unmapped_area(&info);
-
-	/*
-	 * A failed mmap() very likely causes application failure,
-	 * so fall back to the bottom-up function here. This scenario
-	 * can happen with large stack limits and large mmap()
-	 * allocations.
-	 */
-	if (addr & ~PAGE_MASK) {
-		VM_BUG_ON(addr != -ENOMEM);
-		info.flags = 0;
-		info.low_limit = TASK_UNMAPPED_BASE;
-		info.high_limit = TASK_SIZE;
-		addr = vm_unmapped_area(&info);
-	}
-
-	return addr;
-}
-
-unsigned long
-hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
-		unsigned long len, unsigned long pgoff, unsigned long flags)
+#ifdef CONFIG_X86_64
+bool __init arch_hugetlb_valid_size(unsigned long size)
 {
-	struct hstate *h = hstate_file(file);
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-
-	if (len & ~huge_page_mask(h))
-		return -EINVAL;
-	if (len > TASK_SIZE)
-		return -ENOMEM;
-
-	if (flags & MAP_FIXED) {
-		if (prepare_hugepage_range(file, addr, len))
-			return -EINVAL;
-		return addr;
-	}
-
-	if (addr) {
-		addr = ALIGN(addr, huge_page_size(h));
-		vma = find_vma(mm, addr);
-		if (TASK_SIZE - len >= addr &&
-		    (!vma || addr + len <= vma->vm_start))
-			return addr;
-	}
-	if (mm->get_unmapped_area == arch_get_unmapped_area)
-		return hugetlb_get_unmapped_area_bottomup(file, addr, len,
-				pgoff, flags);
+	if (size == PMD_SIZE)
+		return true;
+	else if (size == PUD_SIZE && boot_cpu_has(X86_FEATURE_GBPAGES))
+		return true;
 	else
-		return hugetlb_get_unmapped_area_topdown(file, addr, len,
-				pgoff, flags);
+		return false;
 }
 
-#endif /*HAVE_ARCH_HUGETLB_UNMAPPED_AREA*/
-
-#ifdef CONFIG_X86_64
-static __init int setup_hugepagesz(char *opt)
+#ifdef CONFIG_CONTIG_ALLOC
+static __init int gigantic_pages_init(void)
 {
-	unsigned long ps = memparse(opt, &opt);
-	if (ps == PMD_SIZE) {
-		hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
-	} else if (ps == PUD_SIZE && cpu_has_gbpages) {
+	/* With compaction or CMA we can allocate gigantic pages at runtime */
+	if (boot_cpu_has(X86_FEATURE_GBPAGES))
 		hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
-	} else {
-		printk(KERN_ERR "hugepagesz: Unsupported page size %lu M\n",
-			ps >> 20);
-		return 0;
-	}
-	return 1;
+	return 0;
 }
-__setup("hugepagesz=", setup_hugepagesz);
+arch_initcall(gigantic_pages_init);
+#endif
 #endif