Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/ppc64/mm/hugetlbpage.c b/arch/ppc64/mm/hugetlbpage.c
new file mode 100644
index 0000000..c62ddaf
--- /dev/null
+++ b/arch/ppc64/mm/hugetlbpage.c
@@ -0,0 +1,904 @@
+/*
+ * PPC64 (POWER4) Huge TLB Page Support for Kernel.
+ *
+ * Copyright (C) 2003 David Gibson, IBM Corporation.
+ *
+ * Based on the IA-32 version:
+ * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
+ */
+
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/smp_lock.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/sysctl.h>
+#include <asm/mman.h>
+#include <asm/pgalloc.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
+#include <asm/machdep.h>
+#include <asm/cputable.h>
+#include <asm/tlb.h>
+
+#include <linux/sysctl.h>
+
+#define HUGEPGDIR_SHIFT (HPAGE_SHIFT + PAGE_SHIFT - 3)
+#define HUGEPGDIR_SIZE (1UL << HUGEPGDIR_SHIFT)
+#define HUGEPGDIR_MASK (~(HUGEPGDIR_SIZE-1))
+
+#define HUGEPTE_INDEX_SIZE 9
+#define HUGEPGD_INDEX_SIZE 10
+
+#define PTRS_PER_HUGEPTE (1 << HUGEPTE_INDEX_SIZE)
+#define PTRS_PER_HUGEPGD (1 << HUGEPGD_INDEX_SIZE)
+
+static inline int hugepgd_index(unsigned long addr)
+{
+ return (addr & ~REGION_MASK) >> HUGEPGDIR_SHIFT;
+}
+
+static pgd_t *hugepgd_offset(struct mm_struct *mm, unsigned long addr)
+{
+ int index;
+
+ if (! mm->context.huge_pgdir)
+ return NULL;
+
+
+ index = hugepgd_index(addr);
+ BUG_ON(index >= PTRS_PER_HUGEPGD);
+ return mm->context.huge_pgdir + index;
+}
+
+static inline pte_t *hugepte_offset(pgd_t *dir, unsigned long addr)
+{
+ int index;
+
+ if (pgd_none(*dir))
+ return NULL;
+
+ index = (addr >> HPAGE_SHIFT) % PTRS_PER_HUGEPTE;
+ return (pte_t *)pgd_page(*dir) + index;
+}
+
+static pgd_t *hugepgd_alloc(struct mm_struct *mm, unsigned long addr)
+{
+ BUG_ON(! in_hugepage_area(mm->context, addr));
+
+ if (! mm->context.huge_pgdir) {
+ pgd_t *new;
+ spin_unlock(&mm->page_table_lock);
+ /* Don't use pgd_alloc(), because we want __GFP_REPEAT */
+ new = kmem_cache_alloc(zero_cache, GFP_KERNEL | __GFP_REPEAT);
+ BUG_ON(memcmp(new, empty_zero_page, PAGE_SIZE));
+ spin_lock(&mm->page_table_lock);
+
+ /*
+ * Because we dropped the lock, we should re-check the
+ * entry, as somebody else could have populated it..
+ */
+ if (mm->context.huge_pgdir)
+ pgd_free(new);
+ else
+ mm->context.huge_pgdir = new;
+ }
+ return hugepgd_offset(mm, addr);
+}
+
+static pte_t *hugepte_alloc(struct mm_struct *mm, pgd_t *dir,
+ unsigned long addr)
+{
+ if (! pgd_present(*dir)) {
+ pte_t *new;
+
+ spin_unlock(&mm->page_table_lock);
+ new = kmem_cache_alloc(zero_cache, GFP_KERNEL | __GFP_REPEAT);
+ BUG_ON(memcmp(new, empty_zero_page, PAGE_SIZE));
+ spin_lock(&mm->page_table_lock);
+ /*
+ * Because we dropped the lock, we should re-check the
+ * entry, as somebody else could have populated it..
+ */
+ if (pgd_present(*dir)) {
+ if (new)
+ kmem_cache_free(zero_cache, new);
+ } else {
+ struct page *ptepage;
+
+ if (! new)
+ return NULL;
+ ptepage = virt_to_page(new);
+ ptepage->mapping = (void *) mm;
+ ptepage->index = addr & HUGEPGDIR_MASK;
+ pgd_populate(mm, dir, new);
+ }
+ }
+
+ return hugepte_offset(dir, addr);
+}
+
+static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+{
+ pgd_t *pgd;
+
+ BUG_ON(! in_hugepage_area(mm->context, addr));
+
+ pgd = hugepgd_offset(mm, addr);
+ if (! pgd)
+ return NULL;
+
+ return hugepte_offset(pgd, addr);
+}
+
+static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+{
+ pgd_t *pgd;
+
+ BUG_ON(! in_hugepage_area(mm->context, addr));
+
+ pgd = hugepgd_alloc(mm, addr);
+ if (! pgd)
+ return NULL;
+
+ return hugepte_alloc(mm, pgd, addr);
+}
+
+static void set_huge_pte(struct mm_struct *mm, struct vm_area_struct *vma,
+ unsigned long addr, struct page *page,
+ pte_t *ptep, int write_access)
+{
+ pte_t entry;
+
+ add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
+ if (write_access) {
+ entry =
+ pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot)));
+ } else {
+ entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
+ }
+ entry = pte_mkyoung(entry);
+ entry = pte_mkhuge(entry);
+
+ set_pte_at(mm, addr, ptep, entry);
+}
+
+/*
+ * This function checks for proper alignment of input addr and len parameters.
+ */
+int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
+{
+ if (len & ~HPAGE_MASK)
+ return -EINVAL;
+ if (addr & ~HPAGE_MASK)
+ return -EINVAL;
+ if (! (within_hugepage_low_range(addr, len)
+ || within_hugepage_high_range(addr, len)) )
+ return -EINVAL;
+ return 0;
+}
+
+static void flush_segments(void *parm)
+{
+ u16 segs = (unsigned long) parm;
+ unsigned long i;
+
+ asm volatile("isync" : : : "memory");
+
+ for (i = 0; i < 16; i++) {
+ if (! (segs & (1U << i)))
+ continue;
+ asm volatile("slbie %0" : : "r" (i << SID_SHIFT));
+ }
+
+ asm volatile("isync" : : : "memory");
+}
+
+static int prepare_low_seg_for_htlb(struct mm_struct *mm, unsigned long seg)
+{
+ unsigned long start = seg << SID_SHIFT;
+ unsigned long end = (seg+1) << SID_SHIFT;
+ struct vm_area_struct *vma;
+ unsigned long addr;
+ struct mmu_gather *tlb;
+
+ BUG_ON(seg >= 16);
+
+ /* Check no VMAs are in the region */
+ vma = find_vma(mm, start);
+ if (vma && (vma->vm_start < end))
+ return -EBUSY;
+
+ /* Clean up any leftover PTE pages in the region */
+ spin_lock(&mm->page_table_lock);
+ tlb = tlb_gather_mmu(mm, 0);
+ for (addr = start; addr < end; addr += PMD_SIZE) {
+ pgd_t *pgd = pgd_offset(mm, addr);
+ pmd_t *pmd;
+ struct page *page;
+ pte_t *pte;
+ int i;
+
+ if (pgd_none(*pgd))
+ continue;
+ pmd = pmd_offset(pgd, addr);
+ if (!pmd || pmd_none(*pmd))
+ continue;
+ if (pmd_bad(*pmd)) {
+ pmd_ERROR(*pmd);
+ pmd_clear(pmd);
+ continue;
+ }
+ pte = (pte_t *)pmd_page_kernel(*pmd);
+ /* No VMAs, so there should be no PTEs, check just in case. */
+ for (i = 0; i < PTRS_PER_PTE; i++) {
+ BUG_ON(!pte_none(*pte));
+ pte++;
+ }
+ page = pmd_page(*pmd);
+ pmd_clear(pmd);
+ mm->nr_ptes--;
+ dec_page_state(nr_page_table_pages);
+ pte_free_tlb(tlb, page);
+ }
+ tlb_finish_mmu(tlb, start, end);
+ spin_unlock(&mm->page_table_lock);
+
+ return 0;
+}
+
+static int open_low_hpage_segs(struct mm_struct *mm, u16 newsegs)
+{
+ unsigned long i;
+
+ newsegs &= ~(mm->context.htlb_segs);
+ if (! newsegs)
+ return 0; /* The segments we want are already open */
+
+ for (i = 0; i < 16; i++)
+ if ((1 << i) & newsegs)
+ if (prepare_low_seg_for_htlb(mm, i) != 0)
+ return -EBUSY;
+
+ mm->context.htlb_segs |= newsegs;
+
+ /* update the paca copy of the context struct */
+ get_paca()->context = mm->context;
+
+ /* the context change must make it to memory before the flush,
+ * so that further SLB misses do the right thing. */
+ mb();
+ on_each_cpu(flush_segments, (void *)(unsigned long)newsegs, 0, 1);
+
+ return 0;
+}
+
+int prepare_hugepage_range(unsigned long addr, unsigned long len)
+{
+ if (within_hugepage_high_range(addr, len))
+ return 0;
+ else if ((addr < 0x100000000UL) && ((addr+len) < 0x100000000UL)) {
+ int err;
+ /* Yes, we need both tests, in case addr+len overflows
+ * 64-bit arithmetic */
+ err = open_low_hpage_segs(current->mm,
+ LOW_ESID_MASK(addr, len));
+ if (err)
+ printk(KERN_DEBUG "prepare_hugepage_range(%lx, %lx)"
+ " failed (segs: 0x%04hx)\n", addr, len,
+ LOW_ESID_MASK(addr, len));
+ return err;
+ }
+
+ return -EINVAL;
+}
+
+int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
+ struct vm_area_struct *vma)
+{
+ pte_t *src_pte, *dst_pte, entry;
+ struct page *ptepage;
+ unsigned long addr = vma->vm_start;
+ unsigned long end = vma->vm_end;
+ int err = -ENOMEM;
+
+ while (addr < end) {
+ dst_pte = huge_pte_alloc(dst, addr);
+ if (!dst_pte)
+ goto out;
+
+ src_pte = huge_pte_offset(src, addr);
+ entry = *src_pte;
+
+ ptepage = pte_page(entry);
+ get_page(ptepage);
+ add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
+ set_pte_at(dst, addr, dst_pte, entry);
+
+ addr += HPAGE_SIZE;
+ }
+
+ err = 0;
+ out:
+ return err;
+}
+
+int
+follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
+ struct page **pages, struct vm_area_struct **vmas,
+ unsigned long *position, int *length, int i)
+{
+ unsigned long vpfn, vaddr = *position;
+ int remainder = *length;
+
+ WARN_ON(!is_vm_hugetlb_page(vma));
+
+ vpfn = vaddr/PAGE_SIZE;
+ while (vaddr < vma->vm_end && remainder) {
+ if (pages) {
+ pte_t *pte;
+ struct page *page;
+
+ pte = huge_pte_offset(mm, vaddr);
+
+ /* hugetlb should be locked, and hence, prefaulted */
+ WARN_ON(!pte || pte_none(*pte));
+
+ page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)];
+
+ WARN_ON(!PageCompound(page));
+
+ get_page(page);
+ pages[i] = page;
+ }
+
+ if (vmas)
+ vmas[i] = vma;
+
+ vaddr += PAGE_SIZE;
+ ++vpfn;
+ --remainder;
+ ++i;
+ }
+
+ *length = remainder;
+ *position = vaddr;
+
+ return i;
+}
+
+struct page *
+follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
+{
+ pte_t *ptep;
+ struct page *page;
+
+ if (! in_hugepage_area(mm->context, address))
+ return ERR_PTR(-EINVAL);
+
+ ptep = huge_pte_offset(mm, address);
+ page = pte_page(*ptep);
+ if (page)
+ page += (address % HPAGE_SIZE) / PAGE_SIZE;
+
+ return page;
+}
+
+int pmd_huge(pmd_t pmd)
+{
+ return 0;
+}
+
+struct page *
+follow_huge_pmd(struct mm_struct *mm, unsigned long address,
+ pmd_t *pmd, int write)
+{
+ BUG();
+ return NULL;
+}
+
+void unmap_hugepage_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ unsigned long addr;
+ pte_t *ptep;
+ struct page *page;
+
+ WARN_ON(!is_vm_hugetlb_page(vma));
+ BUG_ON((start % HPAGE_SIZE) != 0);
+ BUG_ON((end % HPAGE_SIZE) != 0);
+
+ for (addr = start; addr < end; addr += HPAGE_SIZE) {
+ pte_t pte;
+
+ ptep = huge_pte_offset(mm, addr);
+ if (!ptep || pte_none(*ptep))
+ continue;
+
+ pte = *ptep;
+ page = pte_page(pte);
+ pte_clear(mm, addr, ptep);
+
+ put_page(page);
+ }
+ add_mm_counter(mm, rss, -((end - start) >> PAGE_SHIFT));
+ flush_tlb_pending();
+}
+
+void hugetlb_free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *prev,
+ unsigned long start, unsigned long end)
+{
+ /* Because the huge pgtables are only 2 level, they can take
+ * at most around 4M, much less than one hugepage which the
+ * process is presumably entitled to use. So we don't bother
+ * freeing up the pagetables on unmap, and wait until
+ * destroy_context() to clean up the lot. */
+}
+
+int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long addr;
+ int ret = 0;
+
+ WARN_ON(!is_vm_hugetlb_page(vma));
+ BUG_ON((vma->vm_start % HPAGE_SIZE) != 0);
+ BUG_ON((vma->vm_end % HPAGE_SIZE) != 0);
+
+ spin_lock(&mm->page_table_lock);
+ for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
+ unsigned long idx;
+ pte_t *pte = huge_pte_alloc(mm, addr);
+ struct page *page;
+
+ if (!pte) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ if (! pte_none(*pte))
+ continue;
+
+ idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
+ + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
+ page = find_get_page(mapping, idx);
+ if (!page) {
+ /* charge the fs quota first */
+ if (hugetlb_get_quota(mapping)) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ page = alloc_huge_page();
+ if (!page) {
+ hugetlb_put_quota(mapping);
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
+ if (! ret) {
+ unlock_page(page);
+ } else {
+ hugetlb_put_quota(mapping);
+ free_huge_page(page);
+ goto out;
+ }
+ }
+ set_huge_pte(mm, vma, addr, page, pte, vma->vm_flags & VM_WRITE);
+ }
+out:
+ spin_unlock(&mm->page_table_lock);
+ return ret;
+}
+
+/* Because we have an exclusive hugepage region which lies within the
+ * normal user address space, we have to take special measures to make
+ * non-huge mmap()s evade the hugepage reserved regions. */
+unsigned long arch_get_unmapped_area(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 start_addr;
+
+ if (len > TASK_SIZE)
+ return -ENOMEM;
+
+ if (addr) {
+ addr = PAGE_ALIGN(addr);
+ vma = find_vma(mm, addr);
+ if (((TASK_SIZE - len) >= addr)
+ && (!vma || (addr+len) <= vma->vm_start)
+ && !is_hugepage_only_range(mm, addr,len))
+ return addr;
+ }
+ start_addr = addr = mm->free_area_cache;
+
+full_search:
+ vma = find_vma(mm, addr);
+ while (TASK_SIZE - len >= addr) {
+ BUG_ON(vma && (addr >= vma->vm_end));
+
+ if (touches_hugepage_low_range(mm, addr, len)) {
+ addr = ALIGN(addr+1, 1<<SID_SHIFT);
+ vma = find_vma(mm, addr);
+ continue;
+ }
+ if (touches_hugepage_high_range(addr, len)) {
+ addr = TASK_HPAGE_END;
+ vma = find_vma(mm, addr);
+ continue;
+ }
+ if (!vma || addr + len <= vma->vm_start) {
+ /*
+ * Remember the place where we stopped the search:
+ */
+ mm->free_area_cache = addr + len;
+ return addr;
+ }
+ addr = vma->vm_end;
+ vma = vma->vm_next;
+ }
+
+ /* Make sure we didn't miss any holes */
+ if (start_addr != TASK_UNMAPPED_BASE) {
+ start_addr = addr = TASK_UNMAPPED_BASE;
+ goto full_search;
+ }
+ return -ENOMEM;
+}
+
+/*
+ * This mmap-allocator allocates new areas top-down from below the
+ * stack's low limit (the base):
+ *
+ * Because we have an exclusive hugepage region which lies within the
+ * normal user address space, we have to take special measures to make
+ * non-huge mmap()s evade the hugepage reserved regions.
+ */
+unsigned long
+arch_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, *prev_vma;
+ struct mm_struct *mm = current->mm;
+ unsigned long base = mm->mmap_base, addr = addr0;
+ int first_time = 1;
+
+ /* requested length too big for entire address space */
+ if (len > TASK_SIZE)
+ return -ENOMEM;
+
+ /* dont allow allocations above current base */
+ if (mm->free_area_cache > base)
+ mm->free_area_cache = base;
+
+ /* requesting a specific address */
+ if (addr) {
+ addr = PAGE_ALIGN(addr);
+ vma = find_vma(mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vma || addr + len <= vma->vm_start)
+ && !is_hugepage_only_range(mm, addr,len))
+ return addr;
+ }
+
+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) & PAGE_MASK;
+ do {
+hugepage_recheck:
+ if (touches_hugepage_low_range(mm, addr, len)) {
+ addr = (addr & ((~0) << SID_SHIFT)) - len;
+ goto hugepage_recheck;
+ } else if (touches_hugepage_high_range(addr, len)) {
+ addr = TASK_HPAGE_BASE - len;
+ }
+
+ /*
+ * 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 */
+ 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;
+
+ /* try just below the current vma->vm_start */
+ addr = vma->vm_start-len;
+ } 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;
+ 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;
+ addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
+ /*
+ * Restore the topdown base:
+ */
+ mm->free_area_cache = base;
+
+ return addr;
+}
+
+static unsigned long htlb_get_low_area(unsigned long len, u16 segmask)
+{
+ unsigned long addr = 0;
+ struct vm_area_struct *vma;
+
+ vma = find_vma(current->mm, addr);
+ while (addr + len <= 0x100000000UL) {
+ BUG_ON(vma && (addr >= vma->vm_end)); /* invariant */
+
+ if (! __within_hugepage_low_range(addr, len, segmask)) {
+ addr = ALIGN(addr+1, 1<<SID_SHIFT);
+ vma = find_vma(current->mm, addr);
+ continue;
+ }
+
+ if (!vma || (addr + len) <= vma->vm_start)
+ return addr;
+ addr = ALIGN(vma->vm_end, HPAGE_SIZE);
+ /* Depending on segmask this might not be a confirmed
+ * hugepage region, so the ALIGN could have skipped
+ * some VMAs */
+ vma = find_vma(current->mm, addr);
+ }
+
+ return -ENOMEM;
+}
+
+static unsigned long htlb_get_high_area(unsigned long len)
+{
+ unsigned long addr = TASK_HPAGE_BASE;
+ struct vm_area_struct *vma;
+
+ vma = find_vma(current->mm, addr);
+ for (vma = find_vma(current->mm, addr);
+ addr + len <= TASK_HPAGE_END;
+ vma = vma->vm_next) {
+ BUG_ON(vma && (addr >= vma->vm_end)); /* invariant */
+ BUG_ON(! within_hugepage_high_range(addr, len));
+
+ if (!vma || (addr + len) <= vma->vm_start)
+ return addr;
+ addr = ALIGN(vma->vm_end, HPAGE_SIZE);
+ /* Because we're in a hugepage region, this alignment
+ * should not skip us over any VMAs */
+ }
+
+ return -ENOMEM;
+}
+
+unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
+ unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ if (len & ~HPAGE_MASK)
+ return -EINVAL;
+
+ if (!cpu_has_feature(CPU_FTR_16M_PAGE))
+ return -EINVAL;
+
+ if (test_thread_flag(TIF_32BIT)) {
+ int lastshift = 0;
+ u16 segmask, cursegs = current->mm->context.htlb_segs;
+
+ /* First see if we can do the mapping in the existing
+ * low hpage segments */
+ addr = htlb_get_low_area(len, cursegs);
+ if (addr != -ENOMEM)
+ return addr;
+
+ for (segmask = LOW_ESID_MASK(0x100000000UL-len, len);
+ ! lastshift; segmask >>=1) {
+ if (segmask & 1)
+ lastshift = 1;
+
+ addr = htlb_get_low_area(len, cursegs | segmask);
+ if ((addr != -ENOMEM)
+ && open_low_hpage_segs(current->mm, segmask) == 0)
+ return addr;
+ }
+ printk(KERN_DEBUG "hugetlb_get_unmapped_area() unable to open"
+ " enough segments\n");
+ return -ENOMEM;
+ } else {
+ return htlb_get_high_area(len);
+ }
+}
+
+void hugetlb_mm_free_pgd(struct mm_struct *mm)
+{
+ int i;
+ pgd_t *pgdir;
+
+ spin_lock(&mm->page_table_lock);
+
+ pgdir = mm->context.huge_pgdir;
+ if (! pgdir)
+ goto out;
+
+ mm->context.huge_pgdir = NULL;
+
+ /* cleanup any hugepte pages leftover */
+ for (i = 0; i < PTRS_PER_HUGEPGD; i++) {
+ pgd_t *pgd = pgdir + i;
+
+ if (! pgd_none(*pgd)) {
+ pte_t *pte = (pte_t *)pgd_page(*pgd);
+ struct page *ptepage = virt_to_page(pte);
+
+ ptepage->mapping = NULL;
+
+ BUG_ON(memcmp(pte, empty_zero_page, PAGE_SIZE));
+ kmem_cache_free(zero_cache, pte);
+ }
+ pgd_clear(pgd);
+ }
+
+ BUG_ON(memcmp(pgdir, empty_zero_page, PAGE_SIZE));
+ kmem_cache_free(zero_cache, pgdir);
+
+ out:
+ spin_unlock(&mm->page_table_lock);
+}
+
+int hash_huge_page(struct mm_struct *mm, unsigned long access,
+ unsigned long ea, unsigned long vsid, int local)
+{
+ pte_t *ptep;
+ unsigned long va, vpn;
+ pte_t old_pte, new_pte;
+ unsigned long hpteflags, prpn;
+ long slot;
+ int err = 1;
+
+ spin_lock(&mm->page_table_lock);
+
+ ptep = huge_pte_offset(mm, ea);
+
+ /* Search the Linux page table for a match with va */
+ va = (vsid << 28) | (ea & 0x0fffffff);
+ vpn = va >> HPAGE_SHIFT;
+
+ /*
+ * If no pte found or not present, send the problem up to
+ * do_page_fault
+ */
+ if (unlikely(!ptep || pte_none(*ptep)))
+ goto out;
+
+/* BUG_ON(pte_bad(*ptep)); */
+
+ /*
+ * Check the user's access rights to the page. If access should be
+ * prevented then send the problem up to do_page_fault.
+ */
+ if (unlikely(access & ~pte_val(*ptep)))
+ goto out;
+ /*
+ * At this point, we have a pte (old_pte) which can be used to build
+ * or update an HPTE. There are 2 cases:
+ *
+ * 1. There is a valid (present) pte with no associated HPTE (this is
+ * the most common case)
+ * 2. There is a valid (present) pte with an associated HPTE. The
+ * current values of the pp bits in the HPTE prevent access
+ * because we are doing software DIRTY bit management and the
+ * page is currently not DIRTY.
+ */
+
+
+ old_pte = *ptep;
+ new_pte = old_pte;
+
+ hpteflags = 0x2 | (! (pte_val(new_pte) & _PAGE_RW));
+ /* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
+ hpteflags |= ((pte_val(new_pte) & _PAGE_EXEC) ? 0 : HW_NO_EXEC);
+
+ /* Check if pte already has an hpte (case 2) */
+ if (unlikely(pte_val(old_pte) & _PAGE_HASHPTE)) {
+ /* There MIGHT be an HPTE for this pte */
+ unsigned long hash, slot;
+
+ hash = hpt_hash(vpn, 1);
+ if (pte_val(old_pte) & _PAGE_SECONDARY)
+ hash = ~hash;
+ slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
+ slot += (pte_val(old_pte) & _PAGE_GROUP_IX) >> 12;
+
+ if (ppc_md.hpte_updatepp(slot, hpteflags, va, 1, local) == -1)
+ pte_val(old_pte) &= ~_PAGE_HPTEFLAGS;
+ }
+
+ if (likely(!(pte_val(old_pte) & _PAGE_HASHPTE))) {
+ unsigned long hash = hpt_hash(vpn, 1);
+ unsigned long hpte_group;
+
+ prpn = pte_pfn(old_pte);
+
+repeat:
+ hpte_group = ((hash & htab_hash_mask) *
+ HPTES_PER_GROUP) & ~0x7UL;
+
+ /* Update the linux pte with the HPTE slot */
+ pte_val(new_pte) &= ~_PAGE_HPTEFLAGS;
+ pte_val(new_pte) |= _PAGE_HASHPTE;
+
+ /* Add in WIMG bits */
+ /* XXX We should store these in the pte */
+ hpteflags |= _PAGE_COHERENT;
+
+ slot = ppc_md.hpte_insert(hpte_group, va, prpn, 0,
+ hpteflags, 0, 1);
+
+ /* Primary is full, try the secondary */
+ if (unlikely(slot == -1)) {
+ pte_val(new_pte) |= _PAGE_SECONDARY;
+ hpte_group = ((~hash & htab_hash_mask) *
+ HPTES_PER_GROUP) & ~0x7UL;
+ slot = ppc_md.hpte_insert(hpte_group, va, prpn,
+ 1, hpteflags, 0, 1);
+ if (slot == -1) {
+ if (mftb() & 0x1)
+ hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+
+ ppc_md.hpte_remove(hpte_group);
+ goto repeat;
+ }
+ }
+
+ if (unlikely(slot == -2))
+ panic("hash_huge_page: pte_insert failed\n");
+
+ pte_val(new_pte) |= (slot<<12) & _PAGE_GROUP_IX;
+
+ /*
+ * No need to use ldarx/stdcx here because all who
+ * might be updating the pte will hold the
+ * page_table_lock
+ */
+ *ptep = new_pte;
+ }
+
+ err = 0;
+
+ out:
+ spin_unlock(&mm->page_table_lock);
+
+ return err;
+}