diff options
Diffstat (limited to 'arch/x86/xen/mmu.c')
| -rw-r--r-- | arch/x86/xen/mmu.c | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index c3b27dec6f0..644232aa7bf 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -56,19 +56,13 @@ #include "multicalls.h" #include "mmu.h" -/* - * This should probably be a config option. On 32-bit, it costs 1 - * page/gig of memory; on 64-bit its 2 pages/gig. If we want it to be - * completely unbounded we can add another level to the p2m structure. - */ -#define MAX_GUEST_PAGES (16ull * 1024*1024*1024 / PAGE_SIZE) #define P2M_ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(unsigned long)) -static unsigned long *p2m_top[MAX_GUEST_PAGES / P2M_ENTRIES_PER_PAGE]; +static unsigned long *p2m_top[MAX_DOMAIN_PAGES / P2M_ENTRIES_PER_PAGE]; static inline unsigned p2m_top_index(unsigned long pfn) { - BUG_ON(pfn >= MAX_GUEST_PAGES); + BUG_ON(pfn >= MAX_DOMAIN_PAGES); return pfn / P2M_ENTRIES_PER_PAGE; } @@ -81,12 +75,9 @@ void __init xen_build_dynamic_phys_to_machine(void) { unsigned pfn; unsigned long *mfn_list = (unsigned long *)xen_start_info->mfn_list; + unsigned long max_pfn = min(MAX_DOMAIN_PAGES, xen_start_info->nr_pages); - BUG_ON(xen_start_info->nr_pages >= MAX_GUEST_PAGES); - - for(pfn = 0; - pfn < xen_start_info->nr_pages; - pfn += P2M_ENTRIES_PER_PAGE) { + for(pfn = 0; pfn < max_pfn; pfn += P2M_ENTRIES_PER_PAGE) { unsigned topidx = p2m_top_index(pfn); p2m_top[topidx] = &mfn_list[pfn]; @@ -97,6 +88,9 @@ unsigned long get_phys_to_machine(unsigned long pfn) { unsigned topidx, idx; + if (unlikely(pfn >= MAX_DOMAIN_PAGES)) + return INVALID_P2M_ENTRY; + topidx = p2m_top_index(pfn); if (p2m_top[topidx] == NULL) return INVALID_P2M_ENTRY; @@ -129,6 +123,11 @@ void set_phys_to_machine(unsigned long pfn, unsigned long mfn) return; } + if (unlikely(pfn >= MAX_DOMAIN_PAGES)) { + BUG_ON(mfn != INVALID_P2M_ENTRY); + return; + } + topidx = p2m_top_index(pfn); if (p2m_top[topidx] == NULL) { /* no need to allocate a page to store an invalid entry */ |