xen/privcmd: improve performance of MMAPBATCH_V2

[cascardo/linux.git] / drivers / xen / xlate_mmu.c

diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c
index 7724d90..58a5389 100644 (file)
--- a/drivers/xen/xlate_mmu.c
+++ b/drivers/xen/xlate_mmu.c
@@ -62,13 +62,15 @@ static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
 }
 
 struct remap_data {
-       xen_pfn_t fgmfn; /* foreign domain's gmfn */
+       xen_pfn_t *fgmfn; /* foreign domain's gmfn */
        pgprot_t prot;
        domid_t  domid;
        struct vm_area_struct *vma;
        int index;
        struct page **pages;
        struct xen_remap_mfn_info *info;
+       int *err_ptr;
+       int mapped;
 };
 
 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
@@ -80,38 +82,46 @@ static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
        pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot));
        int rc;
 
-       rc = map_foreign_page(pfn, info->fgmfn, info->domid);
-       if (rc < 0)
-               return rc;
-       set_pte_at(info->vma->vm_mm, addr, ptep, pte);
+       rc = map_foreign_page(pfn, *info->fgmfn, info->domid);
+       *info->err_ptr++ = rc;
+       if (!rc) {
+               set_pte_at(info->vma->vm_mm, addr, ptep, pte);
+               info->mapped++;
+       }
+       info->fgmfn++;
 
        return 0;
 }
 
-int xen_xlate_remap_gfn_range(struct vm_area_struct *vma,
+int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
                              unsigned long addr,
-                             xen_pfn_t gfn, int nr,
-                             pgprot_t prot, unsigned domid,
+                             xen_pfn_t *mfn, int nr,
+                             int *err_ptr, pgprot_t prot,
+                             unsigned domid,
                              struct page **pages)
 {
        int err;
        struct remap_data data;
+       unsigned long range = nr << PAGE_SHIFT;
 
-       /* TBD: Batching, current sole caller only does page at a time */
-       if (nr > 1)
-               return -EINVAL;
+       /* Kept here for the purpose of making sure code doesn't break
+          x86 PVOPS */
+       BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO)));
 
-       data.fgmfn = gfn;
-       data.prot = prot;
+       data.fgmfn = mfn;
+       data.prot  = prot;
        data.domid = domid;
-       data.vma = vma;
-       data.index = 0;
+       data.vma   = vma;
        data.pages = pages;
-       err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
+       data.index = 0;
+       data.err_ptr = err_ptr;
+       data.mapped = 0;
+
+       err = apply_to_page_range(vma->vm_mm, addr, range,
                                  remap_pte_fn, &data);
-       return err;
+       return err < 0 ? err : data.mapped;
 }
-EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_range);
+EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_array);
 
 int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
                              int nr, struct page **pages)