1 files changed, 357 insertions, 0 deletions

diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
new file mode 100644
index 000000000000..f27d10369e0c
--- /dev/null
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -0,0 +1,357 @@
+/*
+ * SPARC64 Huge TLB page support.
+ *
+ * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net)
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+
+#include <asm/mman.h>
+#include <asm/pgalloc.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+#include <asm/mmu_context.h>
+
+/* Slightly simplified from the non-hugepage variant because by
+ * definition we don't have to worry about any page coloring stuff
+ */
+#define VA_EXCLUDE_START (0x0000080000000000UL - (1UL << 32UL))
+#define VA_EXCLUDE_END   (0xfffff80000000000UL + (1UL << 32UL))
+
+static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp,
+                                                        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 task_size = TASK_SIZE;
+        unsigned long start_addr;
+
+        if (test_thread_flag(TIF_32BIT))
+                task_size = STACK_TOP32;
+        if (unlikely(len >= VA_EXCLUDE_START))
+                return -ENOMEM;
+
+        if (len > mm->cached_hole_size) {
+                start_addr = addr = mm->free_area_cache;
+        } else {
+                start_addr = addr = TASK_UNMAPPED_BASE;
+                mm->cached_hole_size = 0;
+        }
+
+        task_size -= len;
+
+full_search:
+        addr = ALIGN(addr, HPAGE_SIZE);
+
+        for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
+                /* At this point:  (!vma || addr < vma->vm_end). */
+                if (addr < VA_EXCLUDE_START &&
+                    (addr + len) >= VA_EXCLUDE_START) {
+                        addr = VA_EXCLUDE_END;
+                        vma = find_vma(mm, VA_EXCLUDE_END);
+                }
+                if (unlikely(task_size < addr)) {
+                        if (start_addr != TASK_UNMAPPED_BASE) {
+                                start_addr = addr = TASK_UNMAPPED_BASE;
+                                mm->cached_hole_size = 0;
+                                goto full_search;
+                        }
+                        return -ENOMEM;
+                }
+                if (likely(!vma || addr + len <= vma->vm_start)) {
+                        /*
+                         * Remember the place where we stopped the search:
+                         */
+                        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);
+        }
+}
+
+static unsigned long
+hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
+                                  const unsigned long len,
+                                  const unsigned long pgoff,
+                                  const unsigned long flags)
+{
+        struct vm_area_struct *vma;
+        struct mm_struct *mm = current->mm;
+        unsigned long addr = addr0;
+
+        /* This should only ever run for 32-bit processes.  */
+        BUG_ON(!test_thread_flag(TIF_32BIT));
+
+        /* check if free_area_cache is useful for us */
+        if (len <= mm->cached_hole_size) {
+                mm->cached_hole_size = 0;
+                mm->free_area_cache = mm->mmap_base;
+        }
+
+        /* either no address requested or can't fit in requested address hole */
+        addr = mm->free_area_cache & HPAGE_MASK;
+
+        /* make sure it can fit in the remaining address space */
+        if (likely(addr > len)) {
+                vma = find_vma(mm, addr-len);
+                if (!vma || addr <= vma->vm_start) {
+                        /* remember the address as a hint for next time */
+                        return (mm->free_area_cache = addr-len);
+                }
+        }
+
+        if (unlikely(mm->mmap_base < len))
+                goto bottomup;
+
+        addr = (mm->mmap_base-len) & HPAGE_MASK;
+
+        do {
+                /*
+                 * Lookup failure means no vma is above this address,
+                 * else if new region fits below vma->vm_start,
+                 * return with success:
+                 */
+                vma = find_vma(mm, addr);
+                if (likely(!vma || addr+len <= vma->vm_start)) {
+                        /* remember the address as a hint for next time */
+                        return (mm->free_area_cache = addr);
+                }
+
+                /* remember the largest hole we saw so far */
+                if (addr + mm->cached_hole_size < vma->vm_start)
+                        mm->cached_hole_size = vma->vm_start - addr;
+
+                /* try just below the current vma->vm_start */
+                addr = (vma->vm_start-len) & HPAGE_MASK;
+        } while (likely(len < vma->vm_start));
+
+bottomup:
+        /*
+         * 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->cached_hole_size = ~0UL;
+        mm->free_area_cache = TASK_UNMAPPED_BASE;
+        addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
+        /*
+         * Restore the topdown base:
+         */
+        mm->free_area_cache = mm->mmap_base;
+        mm->cached_hole_size = ~0UL;
+
+        return addr;
+}
+
+unsigned long
+hugetlb_get_unmapped_area(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 task_size = TASK_SIZE;
+
+        if (test_thread_flag(TIF_32BIT))
+                task_size = STACK_TOP32;
+
+        if (len & ~HPAGE_MASK)
+                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, HPAGE_SIZE);
+                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);
+        else
+                return hugetlb_get_unmapped_area_topdown(file, addr, len,
+                                pgoff, flags);
+}
+
+pte_t *huge_pte_alloc(struct mm_struct *mm,
+                        unsigned long addr, unsigned long sz)
+{
+        pgd_t *pgd;
+        pud_t *pud;
+        pmd_t *pmd;
+        pte_t *pte = NULL;
+
+        /* We must align the address, because our caller will run
+         * set_huge_pte_at() on whatever we return, which writes out
+         * all of the sub-ptes for the hugepage range.  So we have
+         * to give it the first such sub-pte.
+         */
+        addr &= HPAGE_MASK;
+
+        pgd = pgd_offset(mm, addr);
+        pud = pud_alloc(mm, pgd, addr);
+        if (pud) {
+                pmd = pmd_alloc(mm, pud, addr);
+                if (pmd)
+                        pte = pte_alloc_map(mm, pmd, addr);
+        }
+        return pte;
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+{
+        pgd_t *pgd;
+        pud_t *pud;
+        pmd_t *pmd;
+        pte_t *pte = NULL;
+
+        addr &= HPAGE_MASK;
+
+        pgd = pgd_offset(mm, addr);
+        if (!pgd_none(*pgd)) {
+                pud = pud_offset(pgd, addr);
+                if (!pud_none(*pud)) {
+                        pmd = pmd_offset(pud, addr);
+                        if (!pmd_none(*pmd))
+                                pte = pte_offset_map(pmd, addr);
+                }
+        }
+        return pte;
+}
+
+int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
+{
+        return 0;
+}
+
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+                     pte_t *ptep, pte_t entry)
+{
+        int i;
+
+        if (!pte_present(*ptep) && pte_present(entry))
+                mm->context.huge_pte_count++;
+
+        addr &= HPAGE_MASK;
+        for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+                set_pte_at(mm, addr, ptep, entry);
+                ptep++;
+                addr += PAGE_SIZE;
+                pte_val(entry) += PAGE_SIZE;
+        }
+}
+
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
+                              pte_t *ptep)
+{
+        pte_t entry;
+        int i;
+
+        entry = *ptep;
+        if (pte_present(entry))
+                mm->context.huge_pte_count--;
+
+        addr &= HPAGE_MASK;
+
+        for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+                pte_clear(mm, addr, ptep);
+                addr += PAGE_SIZE;
+                ptep++;
+        }
+
+        return entry;
+}
+
+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 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;
+}
+
+static void context_reload(void *__data)
+{
+        struct mm_struct *mm = __data;
+
+        if (mm == current->mm)
+                load_secondary_context(mm);
+}
+
+void hugetlb_prefault_arch_hook(struct mm_struct *mm)
+{
+        struct tsb_config *tp = &mm->context.tsb_block[MM_TSB_HUGE];
+
+        if (likely(tp->tsb != NULL))
+                return;
+
+        tsb_grow(mm, MM_TSB_HUGE, 0);
+        tsb_context_switch(mm);
+        smp_tsb_sync(mm);
+
+        /* On UltraSPARC-III+ and later, configure the second half of
+         * the Data-TLB for huge pages.
+         */
+        if (tlb_type == cheetah_plus) {
+                unsigned long ctx;
+
+                spin_lock(&ctx_alloc_lock);
+                ctx = mm->context.sparc64_ctx_val;
+                ctx &= ~CTX_PGSZ_MASK;
+                ctx |= CTX_PGSZ_BASE << CTX_PGSZ0_SHIFT;
+                ctx |= CTX_PGSZ_HUGE << CTX_PGSZ1_SHIFT;
+
+                if (ctx != mm->context.sparc64_ctx_val) {
+                        /* When changing the page size fields, we
+                         * must perform a context flush so that no
+                         * stale entries match.  This flush must
+                         * occur with the original context register
+                         * settings.
+                         */
+                        do_flush_tlb_mm(mm);
+
+                        /* Reload the context register of all processors
+                         * also executing in this address space.
+                         */
+                        mm->context.sparc64_ctx_val = ctx;
+                        on_each_cpu(context_reload, mm, 0);
+                }
+                spin_unlock(&ctx_alloc_lock);
+        }
+}