diff options
| -rw-r--r-- | arch/x86/xen/p2m.c | 10 | ||||
| -rw-r--r-- | drivers/xen/Kconfig | 17 | ||||
| -rw-r--r-- | drivers/xen/balloon.c | 23 |
3 files changed, 49 insertions, 1 deletions
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 9f93af56a5fc..b47124d4cd67 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -91,6 +91,12 @@ EXPORT_SYMBOL_GPL(xen_p2m_size); unsigned long xen_max_p2m_pfn __read_mostly; EXPORT_SYMBOL_GPL(xen_max_p2m_pfn); +#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG_LIMIT +#define P2M_LIMIT CONFIG_XEN_BALLOON_MEMORY_HOTPLUG_LIMIT +#else +#define P2M_LIMIT 0 +#endif + static DEFINE_SPINLOCK(p2m_update_lock); static unsigned long *p2m_mid_missing_mfn; @@ -385,9 +391,11 @@ static void __init xen_rebuild_p2m_list(unsigned long *p2m) void __init xen_vmalloc_p2m_tree(void) { static struct vm_struct vm; + unsigned long p2m_limit; + p2m_limit = (phys_addr_t)P2M_LIMIT * 1024 * 1024 * 1024 / PAGE_SIZE; vm.flags = VM_ALLOC; - vm.size = ALIGN(sizeof(unsigned long) * xen_max_p2m_pfn, + vm.size = ALIGN(sizeof(unsigned long) * max(xen_max_p2m_pfn, p2m_limit), PMD_SIZE * PMDS_PER_MID_PAGE); vm_area_register_early(&vm, PMD_SIZE * PMDS_PER_MID_PAGE); pr_notice("p2m virtual area at %p, size is %lx\n", vm.addr, vm.size); diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index b812462083fc..94d96809e686 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -55,6 +55,23 @@ config XEN_BALLOON_MEMORY_HOTPLUG In that case step 3 should be omitted. +config XEN_BALLOON_MEMORY_HOTPLUG_LIMIT + int "Hotplugged memory limit (in GiB) for a PV guest" + default 512 if X86_64 + default 4 if X86_32 + range 0 64 if X86_32 + depends on XEN_HAVE_PVMMU + depends on XEN_BALLOON_MEMORY_HOTPLUG + help + Maxmium amount of memory (in GiB) that a PV guest can be + expanded to when using memory hotplug. + + A PV guest can have more memory than this limit if is + started with a larger maximum. + + This value is used to allocate enough space in internal + tables needed for physical memory administration. + config XEN_SCRUB_PAGES bool "Scrub pages before returning them to system" depends on XEN_BALLOON diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index 0b52d92cb2e5..fd933695f232 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -229,6 +229,29 @@ static enum bp_state reserve_additional_memory(long credit) balloon_hotplug = round_up(balloon_hotplug, PAGES_PER_SECTION); nid = memory_add_physaddr_to_nid(hotplug_start_paddr); +#ifdef CONFIG_XEN_HAVE_PVMMU + /* + * add_memory() will build page tables for the new memory so + * the p2m must contain invalid entries so the correct + * non-present PTEs will be written. + * + * If a failure occurs, the original (identity) p2m entries + * are not restored since this region is now known not to + * conflict with any devices. + */ + if (!xen_feature(XENFEAT_auto_translated_physmap)) { + unsigned long pfn, i; + + pfn = PFN_DOWN(hotplug_start_paddr); + for (i = 0; i < balloon_hotplug; i++) { + if (!set_phys_to_machine(pfn + i, INVALID_P2M_ENTRY)) { + pr_warn("set_phys_to_machine() failed, no memory added\n"); + return BP_ECANCELED; + } + } + } +#endif + rc = add_memory(nid, hotplug_start_paddr, balloon_hotplug << PAGE_SHIFT); if (rc) { |