of/xsysace: Fix OF probing on little-endian systems
[linux-2.6.git] / drivers / xen / balloon.c
index efa4b36..500290b 100644 (file)
@@ -43,6 +43,7 @@
 #include <linux/mutex.h>
 #include <linux/list.h>
 #include <linux/sysdev.h>
+#include <linux/gfp.h>
 
 #include <asm/page.h>
 #include <asm/pgalloc.h>
@@ -52,6 +53,8 @@
 
 #include <asm/xen/hypervisor.h>
 #include <asm/xen/hypercall.h>
+
+#include <xen/xen.h>
 #include <xen/interface/xen.h>
 #include <xen/interface/memory.h>
 #include <xen/xenbus.h>
@@ -66,8 +69,6 @@ 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.
@@ -84,23 +85,12 @@ static struct sys_device balloon_sysdev;
 
 static int register_balloon(struct sys_device *sysdev);
 
-/*
- * Protects atomic reservation decrease/increase against concurrent increases.
- * Also protects non-atomic updates of current_pages and driver_pages, and
- * balloon lists.
- */
-static DEFINE_SPINLOCK(balloon_lock);
-
 static struct balloon_stats balloon_stats;
 
 /* We increase/decrease in batches which fit in a page */
 static unsigned long frame_list[PAGE_SIZE / sizeof(unsigned long)];
 
-/* VM /proc information for memory */
-extern unsigned long totalram_pages;
-
 #ifdef CONFIG_HIGHMEM
-extern unsigned long totalhigh_pages;
 #define inc_totalhigh_pages() (totalhigh_pages++)
 #define dec_totalhigh_pages() (totalhigh_pages--)
 #else
@@ -140,6 +130,8 @@ 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. */
@@ -160,6 +152,8 @@ static struct page *balloon_retrieve(void)
        else
                balloon_stats.balloon_low--;
 
+       totalram_pages++;
+
        return page;
 }
 
@@ -185,7 +179,7 @@ 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 +
@@ -209,35 +203,22 @@ static int increase_reservation(unsigned long nr_pages)
        if (nr_pages > ARRAY_SIZE(frame_list))
                nr_pages = ARRAY_SIZE(frame_list);
 
-       spin_lock_irqsave(&balloon_lock, flags);
+       spin_lock_irqsave(&xen_reservation_lock, flags);
 
        page = balloon_first_page();
        for (i = 0; i < nr_pages; i++) {
                BUG_ON(page == NULL);
-               frame_list[i] = page_to_pfn(page);;
+               frame_list[i] = page_to_pfn(page);
                page = balloon_next_page(page);
        }
 
        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);
 
@@ -263,13 +244,12 @@ 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);
+       spin_unlock_irqrestore(&xen_reservation_lock, flags);
 
-       return 0;
+       return rc < 0 ? rc : rc != nr_pages;
 }
 
 static int decrease_reservation(unsigned long nr_pages)
@@ -312,7 +292,7 @@ static int decrease_reservation(unsigned long nr_pages)
        kmap_flush_unused();
        flush_tlb_all();
 
-       spin_lock_irqsave(&balloon_lock, flags);
+       spin_lock_irqsave(&xen_reservation_lock, flags);
 
        /* No more mappings: invalidate P2M and add to balloon. */
        for (i = 0; i < nr_pages; i++) {
@@ -327,9 +307,8 @@ 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);
+       spin_unlock_irqrestore(&xen_reservation_lock, flags);
 
        return need_sleep;
 }
@@ -371,7 +350,6 @@ 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);
 }
@@ -426,12 +404,10 @@ 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;
@@ -476,9 +452,6 @@ 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,
@@ -513,7 +486,8 @@ static ssize_t show_target(struct sys_device *dev, struct sysdev_attribute *attr
                              char *buf)
 {
        return sprintf(buf, "%llu\n",
-                      (u64)balloon_stats.target_pages << PAGE_SHIFT);
+                      (unsigned long long)balloon_stats.target_pages
+                      << PAGE_SHIFT);
 }
 
 static ssize_t store_target(struct sys_device *dev,
@@ -547,7 +521,6 @@ 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
 };