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Diffstat (limited to 'arch/x86/mm/hugetlbpage.c')
-rw-r--r--arch/x86/mm/hugetlbpage.c327
1 files changed, 58 insertions, 269 deletions
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 0b3d567e686..8b977ebf938 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -9,7 +9,6 @@
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/pagemap.h>
-#include <linux/slab.h>
#include <linux/err.h>
#include <linux/sysctl.h>
#include <asm/mman.h>
@@ -17,146 +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;
-
- /*
- * match the virtual addresses, permission and the alignment of the
- * page table page.
- */
- if (pmd_index(addr) != pmd_index(saddr) ||
- vma->vm_flags != svma->vm_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.
- */
-static void 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 prio_tree_iter iter;
- struct vm_area_struct *svma;
- unsigned long saddr;
- pte_t *spte = NULL;
-
- if (!vma_shareable(vma, addr))
- return;
-
- spin_lock(&mapping->i_mmap_lock);
- vma_prio_tree_foreach(svma, &iter, &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:
- spin_unlock(&mapping->i_mmap_lock);
-}
-
-/*
- * 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)
-{
- pgd_t *pgd;
- pud_t *pud;
- pte_t *pte = NULL;
-
- pgd = pgd_offset(mm, addr);
- pud = pud_alloc(mm, pgd, addr);
- if (pud) {
- if (pud_none(*pud))
- huge_pmd_share(mm, addr, pud);
- 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))
- 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)
@@ -188,13 +47,17 @@ 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 *
@@ -208,149 +71,58 @@ int pmd_huge(pmd_t pmd)
return !!(pmd_val(pmd) & _PAGE_PSE);
}
-struct page *
-follow_huge_pmd(struct mm_struct *mm, unsigned long address,
- pmd_t *pmd, int write)
+int pud_huge(pud_t pud)
{
- struct page *page;
-
- page = pte_page(*(pte_t *)pmd);
- if (page)
- page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
- return page;
+ return !!(pud_val(pud) & _PAGE_PSE);
}
#endif
-/* x86_64 also uses this file */
-
-#ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+#ifdef CONFIG_HUGETLB_PAGE
static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
unsigned long addr, unsigned long len,
unsigned long pgoff, unsigned long flags)
{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- unsigned long start_addr;
-
- if (len > mm->cached_hole_size) {
- start_addr = mm->free_area_cache;
- } else {
- start_addr = TASK_UNMAPPED_BASE;
- mm->cached_hole_size = 0;
- }
-
-full_search:
- addr = ALIGN(start_addr, HPAGE_SIZE);
-
- for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
- /* At this point: (!vma || addr < vma->vm_end). */
- if (TASK_SIZE - len < addr) {
- /*
- * Start a new search - just in case we missed
- * some holes.
- */
- if (start_addr != TASK_UNMAPPED_BASE) {
- start_addr = TASK_UNMAPPED_BASE;
- mm->cached_hole_size = 0;
- goto full_search;
- }
- return -ENOMEM;
- }
- if (!vma || addr + len <= vma->vm_start) {
- mm->free_area_cache = addr + len;
- return addr;
- }
- if (addr + mm->cached_hole_size < vma->vm_start)
- mm->cached_hole_size = vma->vm_start - addr;
- addr = ALIGN(vma->vm_end, HPAGE_SIZE);
- }
+ struct hstate *h = hstate_file(file);
+ struct vm_unmapped_area_info info;
+
+ info.flags = 0;
+ info.length = len;
+ info.low_limit = current->mm->mmap_legacy_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 mm_struct *mm = current->mm;
- struct vm_area_struct *vma, *prev_vma;
- unsigned long base = mm->mmap_base, addr = addr0;
- unsigned long largest_hole = mm->cached_hole_size;
- int first_time = 1;
+ 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);
- /* don't allow allocations above current base */
- if (mm->free_area_cache > base)
- mm->free_area_cache = base;
-
- if (len <= largest_hole) {
- largest_hole = 0;
- mm->free_area_cache = base;
- }
-try_again:
- /* make sure it can fit in the remaining address space */
- if (mm->free_area_cache < len)
- goto fail;
-
- /* either no address requested or cant fit in requested address hole */
- addr = (mm->free_area_cache - len) & HPAGE_MASK;
- do {
- /*
- * Lookup failure means no vma is above this address,
- * i.e. return with success:
- */
- if (!(vma = find_vma_prev(mm, addr, &prev_vma)))
- return addr;
-
- /*
- * new region fits between prev_vma->vm_end and
- * vma->vm_start, use it:
- */
- if (addr + len <= vma->vm_start &&
- (!prev_vma || (addr >= prev_vma->vm_end))) {
- /* remember the address as a hint for next time */
- mm->cached_hole_size = largest_hole;
- return (mm->free_area_cache = addr);
- } else {
- /* pull free_area_cache down to the first hole */
- if (mm->free_area_cache == vma->vm_end) {
- mm->free_area_cache = vma->vm_start;
- mm->cached_hole_size = largest_hole;
- }
- }
-
- /* remember the largest hole we saw so far */
- if (addr + largest_hole < vma->vm_start)
- largest_hole = vma->vm_start - addr;
-
- /* try just below the current vma->vm_start */
- addr = (vma->vm_start - len) & HPAGE_MASK;
- } while (len <= vma->vm_start);
-
-fail:
- /*
- * if hint left us with no space for the requested
- * mapping then try again:
- */
- if (first_time) {
- mm->free_area_cache = base;
- largest_hole = 0;
- first_time = 0;
- goto try_again;
- }
/*
* 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.
*/
- mm->free_area_cache = TASK_UNMAPPED_BASE;
- mm->cached_hole_size = ~0UL;
- addr = hugetlb_get_unmapped_area_bottomup(file, addr0,
- len, pgoff, flags);
-
- /*
- * Restore the topdown base:
- */
- mm->free_area_cache = base;
- mm->cached_hole_size = ~0UL;
+ 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;
}
@@ -359,22 +131,23 @@ unsigned long
hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
unsigned long len, unsigned long pgoff, unsigned long flags)
{
+ struct hstate *h = hstate_file(file);
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
- if (len & ~HPAGE_MASK)
+ if (len & ~huge_page_mask(h))
return -EINVAL;
if (len > TASK_SIZE)
return -ENOMEM;
if (flags & MAP_FIXED) {
- if (prepare_hugepage_range(addr, len))
+ if (prepare_hugepage_range(file, addr, len))
return -EINVAL;
return addr;
}
if (addr) {
- addr = ALIGN(addr, HPAGE_SIZE);
+ addr = ALIGN(addr, huge_page_size(h));
vma = find_vma(mm, addr);
if (TASK_SIZE - len >= addr &&
(!vma || addr + len <= vma->vm_start))
@@ -387,6 +160,22 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
return hugetlb_get_unmapped_area_topdown(file, addr, len,
pgoff, flags);
}
+#endif /* CONFIG_HUGETLB_PAGE */
-#endif /*HAVE_ARCH_HUGETLB_UNMAPPED_AREA*/
-
+#ifdef CONFIG_X86_64
+static __init int setup_hugepagesz(char *opt)
+{
+ 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) {
+ hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
+ } else {
+ printk(KERN_ERR "hugepagesz: Unsupported page size %lu M\n",
+ ps >> 20);
+ return 0;
+ }
+ return 1;
+}
+__setup("hugepagesz=", setup_hugepagesz);
+#endif