From a2e875298729540300a9a0324ee66e3b7883a912 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 26 Aug 2010 16:08:31 -0700 Subject: [PATCH] xen: allocate p2m size based on actual max size Allocate p2m tables based on the actual runtime maximum pfn rather than the static config-time limit. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/mmu.c | 35 +++++++++++++++++++++-------------- 1 file changed, 21 insertions(+), 14 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index ecbdcf0d45d4..151813d97552 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -169,25 +169,27 @@ DEFINE_PER_CPU(unsigned long, xen_current_cr3); /* actual vcpu cr3 */ */ #define USER_LIMIT ((STACK_TOP_MAX + PGDIR_SIZE - 1) & PGDIR_MASK) +static unsigned long max_p2m_pfn __read_mostly = MAX_DOMAIN_PAGES; -#define P2M_ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(unsigned long)) -#define TOP_ENTRIES (MAX_DOMAIN_PAGES / P2M_ENTRIES_PER_PAGE) +#define P2M_ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(unsigned long)) +#define TOP_ENTRIES(pages) ((pages) / P2M_ENTRIES_PER_PAGE) +#define MAX_TOP_ENTRIES TOP_ENTRIES(MAX_DOMAIN_PAGES) /* Placeholder for holes in the address space */ static RESERVE_BRK_ARRAY(unsigned long, p2m_missing, P2M_ENTRIES_PER_PAGE); /* Array of pointers to pages containing p2m entries */ -static RESERVE_BRK_ARRAY(unsigned long *, p2m_top, TOP_ENTRIES); +static RESERVE_BRK_ARRAY(unsigned long *, p2m_top, MAX_TOP_ENTRIES); /* Arrays of p2m arrays expressed in mfns used for save/restore */ -static RESERVE_BRK_ARRAY(unsigned long, p2m_top_mfn, TOP_ENTRIES); +static RESERVE_BRK_ARRAY(unsigned long, p2m_top_mfn, MAX_TOP_ENTRIES); static RESERVE_BRK_ARRAY(unsigned long, p2m_top_mfn_list, - (TOP_ENTRIES / P2M_ENTRIES_PER_PAGE)); + (MAX_TOP_ENTRIES / P2M_ENTRIES_PER_PAGE)); static inline unsigned p2m_top_index(unsigned long pfn) { - BUG_ON(pfn >= MAX_DOMAIN_PAGES); + BUG_ON(pfn >= max_p2m_pfn); return pfn / P2M_ENTRIES_PER_PAGE; } @@ -201,13 +203,15 @@ void xen_build_mfn_list_list(void) { unsigned pfn, idx; - for (pfn = 0; pfn < MAX_DOMAIN_PAGES; pfn += P2M_ENTRIES_PER_PAGE) { + for (pfn = 0; pfn < max_p2m_pfn; pfn += P2M_ENTRIES_PER_PAGE) { unsigned topidx = p2m_top_index(pfn); p2m_top_mfn[topidx] = virt_to_mfn(p2m_top[topidx]); } - for (idx = 0; idx < TOP_ENTRIES/P2M_ENTRIES_PER_PAGE; idx++) { + for (idx = 0; + idx < TOP_ENTRIES(max_p2m_pfn)/P2M_ENTRIES_PER_PAGE; + idx++) { unsigned topidx = idx * P2M_ENTRIES_PER_PAGE; p2m_top_mfn_list[idx] = virt_to_mfn(&p2m_top_mfn[topidx]); } @@ -230,19 +234,22 @@ void __init xen_build_dynamic_phys_to_machine(void) unsigned pfn; unsigned i; + max_p2m_pfn = max_pfn; + p2m_missing = extend_brk(sizeof(*p2m_missing) * P2M_ENTRIES_PER_PAGE, PAGE_SIZE); for (i = 0; i < P2M_ENTRIES_PER_PAGE; i++) p2m_missing[i] = ~0UL; - p2m_top = extend_brk(sizeof(*p2m_top) * TOP_ENTRIES, + p2m_top = extend_brk(sizeof(*p2m_top) * TOP_ENTRIES(max_pfn), PAGE_SIZE); - for (i = 0; i < TOP_ENTRIES; i++) + for (i = 0; i < TOP_ENTRIES(max_pfn); i++) p2m_top[i] = p2m_missing; - p2m_top_mfn = extend_brk(sizeof(*p2m_top_mfn) * TOP_ENTRIES, PAGE_SIZE); + p2m_top_mfn = extend_brk(sizeof(*p2m_top_mfn) * TOP_ENTRIES(max_pfn), + PAGE_SIZE); p2m_top_mfn_list = extend_brk(sizeof(*p2m_top_mfn_list) * - (TOP_ENTRIES / P2M_ENTRIES_PER_PAGE), + (TOP_ENTRIES(max_pfn) / P2M_ENTRIES_PER_PAGE), PAGE_SIZE); for (pfn = 0; pfn < max_pfn; pfn += P2M_ENTRIES_PER_PAGE) { @@ -258,7 +265,7 @@ unsigned long get_phys_to_machine(unsigned long pfn) { unsigned topidx, idx; - if (unlikely(pfn >= MAX_DOMAIN_PAGES)) + if (unlikely(pfn >= max_p2m_pfn)) return INVALID_P2M_ENTRY; topidx = p2m_top_index(pfn); @@ -304,7 +311,7 @@ bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn) { unsigned topidx, idx; - if (unlikely(pfn >= MAX_DOMAIN_PAGES)) { + if (unlikely(pfn >= max_p2m_pfn)) { BUG_ON(mfn != INVALID_P2M_ENTRY); return true; } -- 2.11.0