powerpc/mm: Add radix support for hugetlb

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 87 insertions, 0 deletions

diff --git a/arch/powerpc/mm/hugetlbpage-radix.c b/arch/powerpc/mm/hugetlbpage-radix.c
new file mode 100644
index 000000000000..1e11559e1aac
--- /dev/null
+++ b/arch/powerpc/mm/hugetlbpage-radix.c
@@ -0,0 +1,87 @@
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/cacheflush.h>
+#include <asm/machdep.h>
+#include <asm/mman.h>
+
+void radix__flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+	unsigned long ap, shift;
+	struct hstate *hstate = hstate_file(vma->vm_file);
+
+	shift = huge_page_shift(hstate);
+	if (shift == mmu_psize_defs[MMU_PAGE_2M].shift)
+		ap = mmu_get_ap(MMU_PAGE_2M);
+	else if (shift == mmu_psize_defs[MMU_PAGE_1G].shift)
+		ap = mmu_get_ap(MMU_PAGE_1G);
+	else {
+		WARN(1, "Wrong huge page shift\n");
+		return ;
+	}
+	radix___flush_tlb_page(vma->vm_mm, vmaddr, ap, 0);
+}
+
+void radix__local_flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+	unsigned long ap, shift;
+	struct hstate *hstate = hstate_file(vma->vm_file);
+
+	shift = huge_page_shift(hstate);
+	if (shift == mmu_psize_defs[MMU_PAGE_2M].shift)
+		ap = mmu_get_ap(MMU_PAGE_2M);
+	else if (shift == mmu_psize_defs[MMU_PAGE_1G].shift)
+		ap = mmu_get_ap(MMU_PAGE_1G);
+	else {
+		WARN(1, "Wrong huge page shift\n");
+		return ;
+	}
+	radix___local_flush_tlb_page(vma->vm_mm, vmaddr, ap, 0);
+}
+
+/*
+ * A vairant of hugetlb_get_unmapped_area doing topdown search
+ * FIXME!! should we do as x86 does or non hugetlb area does ?
+ * ie, use topdown or not based on mmap_is_legacy check ?
+ */
+unsigned long
+radix__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;
+	struct hstate *h = hstate_file(file);
+	struct vm_unmapped_area_info info;
+
+	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;
+	}
+	/*
+	 * We are always doing an topdown search here. Slice code
+	 * does that too.
+	 */
+	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;
+	return vm_unmapped_area(&info);
+}