Jiang, Yunhong
2009-Dec-21 05:56 UTC
[Xen-devel] [PATCH 3/3] Check for m2p/compat m2p table for new added memory
Check m2p/compat m2p table for new added memory.
As we allocate m2p/compat m2p/frametable page tables from new added memory, we
want to make sure the new range can hold up the new page tables, this is because
m2p/frametable need be aligned and cover more than the new-added range.
Signed-off-by: Jiang, Yunhong <yunhong.jiang@intel.com>
diff -r 095f03b1a6a9 xen/arch/x86/x86_64/mm.c
--- a/xen/arch/x86/x86_64/mm.c Sun Dec 20 23:00:51 2009 +0800
+++ b/xen/arch/x86/x86_64/mm.c Sun Dec 20 23:15:41 2009 +0800
@@ -1332,6 +1332,8 @@ int transfer_pages_to_heap(struct mem_ho
int mem_hotadd_check(unsigned long spfn, unsigned long epfn)
{
+ unsigned long s, e, length;
+
if ( (spfn >= epfn) || (spfn < max_page) )
return 0;
@@ -1341,7 +1343,31 @@ int mem_hotadd_check(unsigned long spfn,
if ( (spfn | epfn) & pfn_hole_mask )
return 0;
- /* TBD: Need make sure cover to m2p/ft page table */
+ /* Caculate at most required m2p/compat m2p/frametable pages */
+ s = (spfn & ~((1UL << (L2_PAGETABLE_SHIFT - 3)) - 1));
+ e = (epfn + (1UL << (L2_PAGETABLE_SHIFT - 3)) - 1) &
+ ~((1UL << (L2_PAGETABLE_SHIFT - 3)) - 1);
+
+ length = (e - s) * sizeof(unsigned long);
+
+ s = (spfn & ~((1UL << (L2_PAGETABLE_SHIFT - 2)) - 1));
+ e = (epfn + (1UL << (L2_PAGETABLE_SHIFT - 2)) - 1) &
+ ~((1UL << (L2_PAGETABLE_SHIFT - 2)) - 1);
+
+ e = min_t(unsigned long, e,
+ (RDWR_COMPAT_MPT_VIRT_END - RDWR_COMPAT_MPT_VIRT_START) >>
2);
+
+ if ( e > s )
+ length += (e -s) * sizeof(unsigned int);
+
+ s = pfn_to_pdx(spfn) & ~(PDX_GROUP_COUNT - 1);
+ e = ( pfn_to_pdx(epfn) + (PDX_GROUP_COUNT - 1) ) & ~(PDX_GROUP_COUNT -
1);
+
+ length += (e - s) * sizeof(struct page_info);
+
+ if ((length >> PAGE_SHIFT) > (epfn - spfn))
+ return 0;
+
return 1;
}
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