diff options
Diffstat (limited to 'drivers/xen/balloon.c')
| -rw-r--r-- | drivers/xen/balloon.c | 60 |
1 files changed, 42 insertions, 18 deletions
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index 37d06ea624aa..b7a506f2bb14 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -399,11 +399,25 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) state = BP_EAGAIN; break; } + scrub_page(page); - pfn = page_to_pfn(page); - frame_list[i] = pfn_to_mfn(pfn); + frame_list[i] = page_to_pfn(page); + } - scrub_page(page); + /* + * Ensure that ballooned highmem pages don't have kmaps. + * + * Do this before changing the p2m as kmap_flush_unused() + * reads PTEs to obtain pages (and hence needs the original + * p2m entry). + */ + kmap_flush_unused(); + + /* Update direct mapping, invalidate P2M, and add to balloon. */ + for (i = 0; i < nr_pages; i++) { + pfn = frame_list[i]; + frame_list[i] = pfn_to_mfn(pfn); + page = pfn_to_page(pfn); #ifdef CONFIG_XEN_HAVE_PVMMU /* @@ -429,11 +443,9 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) } #endif - balloon_append(pfn_to_page(pfn)); + balloon_append(page); } - /* Ensure that ballooned highmem pages don't have kmaps. */ - kmap_flush_unused(); flush_tlb_all(); set_xen_guest_handle(reservation.extent_start, frame_list); @@ -592,19 +604,29 @@ static void __init balloon_add_region(unsigned long start_pfn, } } +static int alloc_balloon_scratch_page(int cpu) +{ + if (per_cpu(balloon_scratch_page, cpu) != NULL) + return 0; + + per_cpu(balloon_scratch_page, cpu) = alloc_page(GFP_KERNEL); + if (per_cpu(balloon_scratch_page, cpu) == NULL) { + pr_warn("Failed to allocate balloon_scratch_page for cpu %d\n", cpu); + return -ENOMEM; + } + + return 0; +} + + static int balloon_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { int cpu = (long)hcpu; switch (action) { case CPU_UP_PREPARE: - if (per_cpu(balloon_scratch_page, cpu) != NULL) - break; - per_cpu(balloon_scratch_page, cpu) = alloc_page(GFP_KERNEL); - if (per_cpu(balloon_scratch_page, cpu) == NULL) { - pr_warn("Failed to allocate balloon_scratch_page for cpu %d\n", cpu); + if (alloc_balloon_scratch_page(cpu)) return NOTIFY_BAD; - } break; default: break; @@ -624,15 +646,17 @@ static int __init balloon_init(void) return -ENODEV; if (!xen_feature(XENFEAT_auto_translated_physmap)) { - for_each_online_cpu(cpu) - { - per_cpu(balloon_scratch_page, cpu) = alloc_page(GFP_KERNEL); - if (per_cpu(balloon_scratch_page, cpu) == NULL) { - pr_warn("Failed to allocate balloon_scratch_page for cpu %d\n", cpu); + register_cpu_notifier(&balloon_cpu_notifier); + + get_online_cpus(); + for_each_online_cpu(cpu) { + if (alloc_balloon_scratch_page(cpu)) { + put_online_cpus(); + unregister_cpu_notifier(&balloon_cpu_notifier); return -ENOMEM; } } - register_cpu_notifier(&balloon_cpu_notifier); + put_online_cpus(); } pr_info("Initialising balloon driver\n"); |