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| author | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2010-08-27 00:04:48 +0200 |
|---|---|---|
| committer | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2010-10-22 21:57:18 +0200 |
| commit | a171ce6e7b4d967b9f9b8ba7c076a8a6d26e432b (patch) | |
| tree | 390e26005e9e49c8926b33b134b0b74c7dbf9b8f /arch | |
| parent | x86: add RESERVE_BRK_ARRAY() helper (diff) | |
| download | linux-a171ce6e7b4d967b9f9b8ba7c076a8a6d26e432b.tar.xz linux-a171ce6e7b4d967b9f9b8ba7c076a8a6d26e432b.zip | |
xen: dynamically allocate p2m space
Use early brk mechanism to allocate p2m tables, to save memory when
booting non-Xen.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/xen/mmu.c | 30 |
1 files changed, 22 insertions, 8 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 42086ac406af..ecbdcf0d45d4 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -174,18 +174,16 @@ DEFINE_PER_CPU(unsigned long, xen_current_cr3); /* actual vcpu cr3 */ #define TOP_ENTRIES (MAX_DOMAIN_PAGES / P2M_ENTRIES_PER_PAGE) /* Placeholder for holes in the address space */ -static unsigned long p2m_missing[P2M_ENTRIES_PER_PAGE] __page_aligned_data = - { [ 0 ... P2M_ENTRIES_PER_PAGE-1 ] = ~0UL }; +static RESERVE_BRK_ARRAY(unsigned long, p2m_missing, P2M_ENTRIES_PER_PAGE); /* Array of pointers to pages containing p2m entries */ -static unsigned long *p2m_top[TOP_ENTRIES] __page_aligned_data = - { [ 0 ... TOP_ENTRIES - 1] = &p2m_missing[0] }; +static RESERVE_BRK_ARRAY(unsigned long *, p2m_top, TOP_ENTRIES); /* Arrays of p2m arrays expressed in mfns used for save/restore */ -static unsigned long p2m_top_mfn[TOP_ENTRIES] __page_aligned_bss; +static RESERVE_BRK_ARRAY(unsigned long, p2m_top_mfn, TOP_ENTRIES); -static unsigned long p2m_top_mfn_list[TOP_ENTRIES / P2M_ENTRIES_PER_PAGE] - __page_aligned_bss; +static RESERVE_BRK_ARRAY(unsigned long, p2m_top_mfn_list, + (TOP_ENTRIES / P2M_ENTRIES_PER_PAGE)); static inline unsigned p2m_top_index(unsigned long pfn) { @@ -209,7 +207,7 @@ void xen_build_mfn_list_list(void) p2m_top_mfn[topidx] = virt_to_mfn(p2m_top[topidx]); } - for (idx = 0; idx < ARRAY_SIZE(p2m_top_mfn_list); idx++) { + for (idx = 0; idx < TOP_ENTRIES/P2M_ENTRIES_PER_PAGE; idx++) { unsigned topidx = idx * P2M_ENTRIES_PER_PAGE; p2m_top_mfn_list[idx] = virt_to_mfn(&p2m_top_mfn[topidx]); } @@ -230,6 +228,22 @@ void __init xen_build_dynamic_phys_to_machine(void) unsigned long *mfn_list = (unsigned long *)xen_start_info->mfn_list; unsigned long max_pfn = min(MAX_DOMAIN_PAGES, xen_start_info->nr_pages); unsigned pfn; + unsigned i; + + 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, + PAGE_SIZE); + for (i = 0; i < TOP_ENTRIES; i++) + p2m_top[i] = p2m_missing; + + p2m_top_mfn = extend_brk(sizeof(*p2m_top_mfn) * TOP_ENTRIES, PAGE_SIZE); + p2m_top_mfn_list = extend_brk(sizeof(*p2m_top_mfn_list) * + (TOP_ENTRIES / P2M_ENTRIES_PER_PAGE), + PAGE_SIZE); for (pfn = 0; pfn < max_pfn; pfn += P2M_ENTRIES_PER_PAGE) { unsigned topidx = p2m_top_index(pfn); |