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-rw-r--r--arch/x86/mm/fault.c14
-rw-r--r--arch/x86/mm/hugetlbpage.c187
-rw-r--r--arch/x86/mm/init.c4
-rw-r--r--arch/x86/mm/mmap.c6
4 files changed, 15 insertions, 196 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 654be4ae304..c1e9e4cbbd7 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -989,6 +989,12 @@ static int fault_in_kernel_space(unsigned long address)
static inline bool smap_violation(int error_code, struct pt_regs *regs)
{
+ if (!IS_ENABLED(CONFIG_X86_SMAP))
+ return false;
+
+ if (!static_cpu_has(X86_FEATURE_SMAP))
+ return false;
+
if (error_code & PF_USER)
return false;
@@ -1091,11 +1097,9 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code)
if (unlikely(error_code & PF_RSVD))
pgtable_bad(regs, error_code, address);
- if (static_cpu_has(X86_FEATURE_SMAP)) {
- if (unlikely(smap_violation(error_code, regs))) {
- bad_area_nosemaphore(regs, error_code, address);
- return;
- }
+ if (unlikely(smap_violation(error_code, regs))) {
+ bad_area_nosemaphore(regs, error_code, address);
+ return;
}
perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index ae1aa71d011..7e73e8c6909 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -16,169 +16,6 @@
#include <asm/tlbflush.h>
#include <asm/pgalloc.h>
-static unsigned long page_table_shareable(struct vm_area_struct *svma,
- struct vm_area_struct *vma,
- unsigned long addr, pgoff_t idx)
-{
- unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) +
- svma->vm_start;
- unsigned long sbase = saddr & PUD_MASK;
- unsigned long s_end = sbase + PUD_SIZE;
-
- /* Allow segments to share if only one is marked locked */
- unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED;
- unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED;
-
- /*
- * match the virtual addresses, permission and the alignment of the
- * page table page.
- */
- if (pmd_index(addr) != pmd_index(saddr) ||
- vm_flags != svm_flags ||
- sbase < svma->vm_start || svma->vm_end < s_end)
- return 0;
-
- return saddr;
-}
-
-static int vma_shareable(struct vm_area_struct *vma, unsigned long addr)
-{
- unsigned long base = addr & PUD_MASK;
- unsigned long end = base + PUD_SIZE;
-
- /*
- * check on proper vm_flags and page table alignment
- */
- if (vma->vm_flags & VM_MAYSHARE &&
- vma->vm_start <= base && end <= vma->vm_end)
- return 1;
- return 0;
-}
-
-/*
- * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc()
- * and returns the corresponding pte. While this is not necessary for the
- * !shared pmd case because we can allocate the pmd later as well, it makes the
- * code much cleaner. pmd allocation is essential for the shared case because
- * pud has to be populated inside the same i_mmap_mutex section - otherwise
- * racing tasks could either miss the sharing (see huge_pte_offset) or select a
- * bad pmd for sharing.
- */
-static pte_t *
-huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
-{
- struct vm_area_struct *vma = find_vma(mm, addr);
- struct address_space *mapping = vma->vm_file->f_mapping;
- pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
- vma->vm_pgoff;
- struct vm_area_struct *svma;
- unsigned long saddr;
- pte_t *spte = NULL;
- pte_t *pte;
-
- if (!vma_shareable(vma, addr))
- return (pte_t *)pmd_alloc(mm, pud, addr);
-
- mutex_lock(&mapping->i_mmap_mutex);
- vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) {
- if (svma == vma)
- continue;
-
- saddr = page_table_shareable(svma, vma, addr, idx);
- if (saddr) {
- spte = huge_pte_offset(svma->vm_mm, saddr);
- if (spte) {
- get_page(virt_to_page(spte));
- break;
- }
- }
- }
-
- if (!spte)
- goto out;
-
- spin_lock(&mm->page_table_lock);
- if (pud_none(*pud))
- pud_populate(mm, pud, (pmd_t *)((unsigned long)spte & PAGE_MASK));
- else
- put_page(virt_to_page(spte));
- spin_unlock(&mm->page_table_lock);
-out:
- pte = (pte_t *)pmd_alloc(mm, pud, addr);
- mutex_unlock(&mapping->i_mmap_mutex);
- return pte;
-}
-
-/*
- * unmap huge page backed by shared pte.
- *
- * Hugetlb pte page is ref counted at the time of mapping. If pte is shared
- * indicated by page_count > 1, unmap is achieved by clearing pud and
- * decrementing the ref count. If count == 1, the pte page is not shared.
- *
- * called with vma->vm_mm->page_table_lock held.
- *
- * returns: 1 successfully unmapped a shared pte page
- * 0 the underlying pte page is not shared, or it is the last user
- */
-int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
-{
- pgd_t *pgd = pgd_offset(mm, *addr);
- pud_t *pud = pud_offset(pgd, *addr);
-
- BUG_ON(page_count(virt_to_page(ptep)) == 0);
- if (page_count(virt_to_page(ptep)) == 1)
- return 0;
-
- pud_clear(pud);
- put_page(virt_to_page(ptep));
- *addr = ALIGN(*addr, HPAGE_SIZE * PTRS_PER_PTE) - HPAGE_SIZE;
- return 1;
-}
-
-pte_t *huge_pte_alloc(struct mm_struct *mm,
- unsigned long addr, unsigned long sz)
-{
- pgd_t *pgd;
- pud_t *pud;
- pte_t *pte = NULL;
-
- pgd = pgd_offset(mm, addr);
- pud = pud_alloc(mm, pgd, addr);
- if (pud) {
- if (sz == PUD_SIZE) {
- pte = (pte_t *)pud;
- } else {
- BUG_ON(sz != PMD_SIZE);
- if (pud_none(*pud))
- pte = huge_pmd_share(mm, addr, pud);
- else
- pte = (pte_t *)pmd_alloc(mm, pud, addr);
- }
- }
- BUG_ON(pte && !pte_none(*pte) && !pte_huge(*pte));
-
- return pte;
-}
-
-pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
-{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd = NULL;
-
- pgd = pgd_offset(mm, addr);
- if (pgd_present(*pgd)) {
- pud = pud_offset(pgd, addr);
- if (pud_present(*pud)) {
- if (pud_large(*pud))
- return (pte_t *)pud;
- pmd = pmd_offset(pud, addr);
- }
- }
- return (pte_t *) pmd;
-}
-
#if 0 /* This is just for testing */
struct page *
follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
@@ -240,30 +77,6 @@ int pud_huge(pud_t pud)
return !!(pud_val(pud) & _PAGE_PSE);
}
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
- pmd_t *pmd, int write)
-{
- struct page *page;
-
- page = pte_page(*(pte_t *)pmd);
- if (page)
- page += ((address & ~PMD_MASK) >> PAGE_SHIFT);
- return page;
-}
-
-struct page *
-follow_huge_pud(struct mm_struct *mm, unsigned long address,
- pud_t *pud, int write)
-{
- struct page *page;
-
- page = pte_page(*(pte_t *)pud);
- if (page)
- page += ((address & ~PUD_MASK) >> PAGE_SHIFT);
- return page;
-}
-
#endif
/* x86_64 also uses this file */
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 1f34e921977..7a5bf1b76e2 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -78,8 +78,8 @@ __ref void *alloc_low_pages(unsigned int num)
return __va(pfn << PAGE_SHIFT);
}
-/* need 4 4k for initial PMD_SIZE, 4k for 0-ISA_END_ADDRESS */
-#define INIT_PGT_BUF_SIZE (5 * PAGE_SIZE)
+/* need 3 4k for initial PMD_SIZE, 3 4k for 0-ISA_END_ADDRESS */
+#define INIT_PGT_BUF_SIZE (6 * PAGE_SIZE)
RESERVE_BRK(early_pgt_alloc, INIT_PGT_BUF_SIZE);
void __init early_alloc_pgt_buf(void)
{
diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 845df6835f9..5c1ae28825c 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -112,12 +112,14 @@ static unsigned long mmap_legacy_base(void)
*/
void arch_pick_mmap_layout(struct mm_struct *mm)
{
+ mm->mmap_legacy_base = mmap_legacy_base();
+ mm->mmap_base = mmap_base();
+
if (mmap_is_legacy()) {
- mm->mmap_base = mmap_legacy_base();
+ mm->mmap_base = mm->mmap_legacy_base;
mm->get_unmapped_area = arch_get_unmapped_area;
mm->unmap_area = arch_unmap_area;
} else {
- mm->mmap_base = mmap_base();
mm->get_unmapped_area = arch_get_unmapped_area_topdown;
mm->unmap_area = arch_unmap_area_topdown;
}