Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes...
[linux-2.6.git] / drivers / xen / balloon.c
index 826dda4..f6738d8 100644 (file)
@@ -68,8 +68,6 @@ struct balloon_stats {
        /* We aim for 'current allocation' == 'target allocation'. */
        unsigned long current_pages;
        unsigned long target_pages;
-       /* We may hit the hard limit in Xen. If we do then we remember it. */
-       unsigned long hard_limit;
        /*
         * Drivers may alter the memory reservation independently, but they
         * must inform the balloon driver so we avoid hitting the hard limit.
@@ -138,6 +136,8 @@ static void balloon_append(struct page *page)
                list_add(&page->lru, &ballooned_pages);
                balloon_stats.balloon_low++;
        }
+
+       totalram_pages--;
 }
 
 /* balloon_retrieve: rescue a page from the balloon, if it is not empty. */
@@ -158,6 +158,8 @@ static struct page *balloon_retrieve(void)
        else
                balloon_stats.balloon_low--;
 
+       totalram_pages++;
+
        return page;
 }
 
@@ -183,7 +185,7 @@ static void balloon_alarm(unsigned long unused)
 
 static unsigned long current_target(void)
 {
-       unsigned long target = min(balloon_stats.target_pages, balloon_stats.hard_limit);
+       unsigned long target = balloon_stats.target_pages;
 
        target = min(target,
                     balloon_stats.current_pages +
@@ -219,23 +221,10 @@ static int increase_reservation(unsigned long nr_pages)
        set_xen_guest_handle(reservation.extent_start, frame_list);
        reservation.nr_extents = nr_pages;
        rc = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
-       if (rc < nr_pages) {
-               if (rc > 0) {
-                       int ret;
-
-                       /* We hit the Xen hard limit: reprobe. */
-                       reservation.nr_extents = rc;
-                       ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
-                                                  &reservation);
-                       BUG_ON(ret != rc);
-               }
-               if (rc >= 0)
-                       balloon_stats.hard_limit = (balloon_stats.current_pages + rc -
-                                                   balloon_stats.driver_pages);
+       if (rc < 0)
                goto out;
-       }
 
-       for (i = 0; i < nr_pages; i++) {
+       for (i = 0; i < rc; i++) {
                page = balloon_retrieve();
                BUG_ON(page == NULL);
 
@@ -261,13 +250,12 @@ static int increase_reservation(unsigned long nr_pages)
                __free_page(page);
        }
 
-       balloon_stats.current_pages += nr_pages;
-       totalram_pages = balloon_stats.current_pages;
+       balloon_stats.current_pages += rc;
 
  out:
        spin_unlock_irqrestore(&balloon_lock, flags);
 
-       return 0;
+       return rc < 0 ? rc : rc != nr_pages;
 }
 
 static int decrease_reservation(unsigned long nr_pages)
@@ -325,7 +313,6 @@ static int decrease_reservation(unsigned long nr_pages)
        BUG_ON(ret != nr_pages);
 
        balloon_stats.current_pages -= nr_pages;
-       totalram_pages = balloon_stats.current_pages;
 
        spin_unlock_irqrestore(&balloon_lock, flags);
 
@@ -369,7 +356,6 @@ static void balloon_process(struct work_struct *work)
 static void balloon_set_new_target(unsigned long target)
 {
        /* No need for lock. Not read-modify-write updates. */
-       balloon_stats.hard_limit   = ~0UL;
        balloon_stats.target_pages = target;
        schedule_work(&balloon_worker);
 }
@@ -424,12 +410,10 @@ static int __init balloon_init(void)
        pr_info("xen_balloon: Initialising balloon driver.\n");
 
        balloon_stats.current_pages = min(xen_start_info->nr_pages, max_pfn);
-       totalram_pages   = balloon_stats.current_pages;
        balloon_stats.target_pages  = balloon_stats.current_pages;
        balloon_stats.balloon_low   = 0;
        balloon_stats.balloon_high  = 0;
        balloon_stats.driver_pages  = 0UL;
-       balloon_stats.hard_limit    = ~0UL;
 
        init_timer(&balloon_timer);
        balloon_timer.data = 0;
@@ -474,9 +458,6 @@ module_exit(balloon_exit);
 BALLOON_SHOW(current_kb, "%lu\n", PAGES2KB(balloon_stats.current_pages));
 BALLOON_SHOW(low_kb, "%lu\n", PAGES2KB(balloon_stats.balloon_low));
 BALLOON_SHOW(high_kb, "%lu\n", PAGES2KB(balloon_stats.balloon_high));
-BALLOON_SHOW(hard_limit_kb,
-            (balloon_stats.hard_limit!=~0UL) ? "%lu\n" : "???\n",
-            (balloon_stats.hard_limit!=~0UL) ? PAGES2KB(balloon_stats.hard_limit) : 0);
 BALLOON_SHOW(driver_kb, "%lu\n", PAGES2KB(balloon_stats.driver_pages));
 
 static ssize_t show_target_kb(struct sys_device *dev, struct sysdev_attribute *attr,
@@ -546,7 +527,6 @@ static struct attribute *balloon_info_attrs[] = {
        &attr_current_kb.attr,
        &attr_low_kb.attr,
        &attr_high_kb.attr,
-       &attr_hard_limit_kb.attr,
        &attr_driver_kb.attr,
        NULL
 };