Dynamically allocate mmu_update array in

direct_remap_pfn_range(). This allows larger batches and
avoids stack overflow.

Signed-off-by: Keir Fraser <keir@xensource.com>

diff --git a/linux-2.6-xen-sparse/arch/xen/i386/mm/ioremap.c b/linux-2.6-xen-sparse/arch/xen/i386/mm/ioremap.c
index dea309b13cbd552341b50e5fa8307662664e91c7..7d989863df993446c48f54c0769e0aba672f4e77 100644 (file)
--- a/linux-2.6-xen-sparse/arch/xen/i386/mm/ioremap.c
+++ b/linux-2.6-xen-sparse/arch/xen/i386/mm/ioremap.c
@@ -52,24 +52,30 @@ static int __direct_remap_pfn_range(struct mm_struct *mm,
                                    pgprot_t prot,
                                    domid_t  domid)
 {
-       int i;
+       int i, rc;
        unsigned long start_address;
-#define MAX_DIRECTMAP_MMU_QUEUE 130
-       mmu_update_t u[MAX_DIRECTMAP_MMU_QUEUE], *v = u, *w = u;
+       mmu_update_t *u, *v, *w;
+
+       u = v = w = (mmu_update_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
+       if (u == NULL)
+               return -ENOMEM;
 
        start_address = address;
 
        flush_cache_all();
 
        for (i = 0; i < size; i += PAGE_SIZE) {
-               if ((v - u) == MAX_DIRECTMAP_MMU_QUEUE) {
+               if ((v - u) == (PAGE_SIZE / sizeof(mmu_update_t))) {
                        /* Fill in the PTE pointers. */
-                       generic_page_range(mm, start_address, 
-                                          address - start_address,
-                                          direct_remap_area_pte_fn, &w);
+                       rc = generic_page_range(mm, start_address, 
+                                               address - start_address,
+                                               direct_remap_area_pte_fn, &w);
+                       if (rc)
+                               goto out;
                        w = u;
+                       rc = -EFAULT;
                        if (HYPERVISOR_mmu_update(u, v - u, NULL, domid) < 0)
-                               return -EFAULT;
+                               goto out;
                        v = u;
                        start_address = address;
                }
@@ -89,13 +95,19 @@ static int __direct_remap_pfn_range(struct mm_struct *mm,
                /* get the ptep's filled in */
                generic_page_range(mm, start_address, address - start_address,
                                   direct_remap_area_pte_fn, &w);
+               rc = -EFAULT;
                if (unlikely(HYPERVISOR_mmu_update(u, v - u, NULL, domid) < 0))
-                       return -EFAULT;
+                       goto out;
        }
 
+       rc = 0;
+
+ out:
        flush_tlb_all();
 
-       return 0;
+       free_page((unsigned long)u);
+
+       return rc;
 }
 
 int direct_remap_pfn_range(struct vm_area_struct *vma,