diff options
Diffstat (limited to 'drivers/xen/balloon.c')
-rw-r--r-- | drivers/xen/balloon.c | 33 |
1 files changed, 19 insertions, 14 deletions
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index 4c02e2b94103..61a6ac8fa8fc 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -157,13 +157,6 @@ static struct page *balloon_retrieve(bool prefer_highmem) return page; } -static struct page *balloon_first_page(void) -{ - if (list_empty(&ballooned_pages)) - return NULL; - return list_entry(ballooned_pages.next, struct page, lru); -} - static struct page *balloon_next_page(struct page *page) { struct list_head *next = page->lru.next; @@ -328,7 +321,7 @@ static enum bp_state increase_reservation(unsigned long nr_pages) if (nr_pages > ARRAY_SIZE(frame_list)) nr_pages = ARRAY_SIZE(frame_list); - page = balloon_first_page(); + page = list_first_entry_or_null(&ballooned_pages, struct page, lru); for (i = 0; i < nr_pages; i++) { if (!page) { nr_pages = i; @@ -406,11 +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 /* @@ -436,11 +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); |