xen/mmu: Cleanup xen_pagetable_p2m_copy a bit.
Stefano noticed that the code runs only under 64-bit so
the comments about 32-bit are pointless.
Also we change the condition for xen_revector_p2m_tree
returning the same value (because it could not allocate
a swath of space to put the new P2M in) or it had been
called once already. In such we return early from the
function.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index c140eff..9d74249 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1209,29 +1209,29 @@
size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long));
- /* On 32-bit, we get zero so this never gets executed. */
new_mfn_list = xen_revector_p2m_tree();
- if (new_mfn_list && new_mfn_list != xen_start_info->mfn_list) {
- /* using __ka address and sticking INVALID_P2M_ENTRY! */
- memset((void *)xen_start_info->mfn_list, 0xff, size);
-
- /* We should be in __ka space. */
- BUG_ON(xen_start_info->mfn_list < __START_KERNEL_map);
- addr = xen_start_info->mfn_list;
- /* We roundup to the PMD, which means that if anybody at this stage is
- * using the __ka address of xen_start_info or xen_start_info->shared_info
- * they are in going to crash. Fortunatly we have already revectored
- * in xen_setup_kernel_pagetable and in xen_setup_shared_info. */
- size = roundup(size, PMD_SIZE);
- xen_cleanhighmap(addr, addr + size);
-
- size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long));
- memblock_free(__pa(xen_start_info->mfn_list), size);
- /* And revector! Bye bye old array */
- xen_start_info->mfn_list = new_mfn_list;
- } else
+ /* No memory or already called. */
+ if (!new_mfn_list || new_mfn_list == xen_start_info->mfn_list)
return;
+ /* using __ka address and sticking INVALID_P2M_ENTRY! */
+ memset((void *)xen_start_info->mfn_list, 0xff, size);
+
+ /* We should be in __ka space. */
+ BUG_ON(xen_start_info->mfn_list < __START_KERNEL_map);
+ addr = xen_start_info->mfn_list;
+ /* We roundup to the PMD, which means that if anybody at this stage is
+ * using the __ka address of xen_start_info or xen_start_info->shared_info
+ * they are in going to crash. Fortunatly we have already revectored
+ * in xen_setup_kernel_pagetable and in xen_setup_shared_info. */
+ size = roundup(size, PMD_SIZE);
+ xen_cleanhighmap(addr, addr + size);
+
+ size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long));
+ memblock_free(__pa(xen_start_info->mfn_list), size);
+ /* And revector! Bye bye old array */
+ xen_start_info->mfn_list = new_mfn_list;
+
/* At this stage, cleanup_highmap has already cleaned __ka space
* from _brk_limit way up to the max_pfn_mapped (which is the end of
* the ramdisk). We continue on, erasing PMD entries that point to page