[PATCH RESEND 2/4] hv_balloon: simplify hv_online_page()/hv_page_online_one()

[Vitaly Kuznetsov]

Instead of doing pfn_to_page() and continuosly casting page to unsigned
long just cache the pfn of the page with page_to_pfn().

Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com>
---
 drivers/hv/hv_balloon.c | 27 +++++----------------------
 1 file changed, 5 insertions(+), 22 deletions(-)

diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index 1aece72da9ba..5b8e1ad1bcfe 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -612,28 +612,17 @@ static struct notifier_block hv_memory_nb = {
 /* Check if the particular page is backed and can be onlined and online it. */
 static void hv_page_online_one(struct hv_hotadd_state *has, struct page *pg)
 {
-       unsigned long cur_start_pgp;
-       unsigned long cur_end_pgp;
        struct hv_hotadd_gap *gap;
-
-       cur_start_pgp = (unsigned long)pfn_to_page(has->covered_start_pfn);
-       cur_end_pgp = (unsigned long)pfn_to_page(has->covered_end_pfn);
+       unsigned long pfn = page_to_pfn(pg);
 
        /* The page is not backed. */
-       if (((unsigned long)pg < cur_start_pgp) ||
-           ((unsigned long)pg >= cur_end_pgp))
+       if ((pfn < has->covered_start_pfn) || (pfn >= has->covered_end_pfn))
                return;
 
        /* Check for gaps. */
        list_for_each_entry(gap, &has->gap_list, list) {
-               cur_start_pgp = (unsigned long)
-                       pfn_to_page(gap->start_pfn);
-               cur_end_pgp = (unsigned long)
-                       pfn_to_page(gap->end_pfn);
-               if (((unsigned long)pg >= cur_start_pgp) &&
-                   ((unsigned long)pg < cur_end_pgp)) {
+               if ((pfn >= gap->start_pfn) && (pfn < gap->end_pfn))
                        return;
-               }
        }
 
        /* This frame is currently backed; online the page. */
@@ -726,19 +715,13 @@ static void hv_mem_hot_add(unsigned long start, unsigned 
long size,
 static void hv_online_page(struct page *pg)
 {
        struct hv_hotadd_state *has;
-       unsigned long cur_start_pgp;
-       unsigned long cur_end_pgp;
        unsigned long flags;
+       unsigned long pfn = page_to_pfn(pg);
 
        spin_lock_irqsave(&dm_device.ha_lock, flags);
        list_for_each_entry(has, &dm_device.ha_region_list, list) {
-               cur_start_pgp = (unsigned long)
-                       pfn_to_page(has->start_pfn);
-               cur_end_pgp = (unsigned long)pfn_to_page(has->end_pfn);
-
                /* The page belongs to a different HAS. */
-               if (((unsigned long)pg < cur_start_pgp) ||
-                   ((unsigned long)pg >= cur_end_pgp))
+               if ((pfn < has->start_pfn) || (pfn >= has->end_pfn))
                        continue;
 
                hv_page_online_one(has, pg);
-- 
2.14.3