Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp

[karo-tx-linux.git] / drivers / xen / balloon.c

diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 1a0d8c2a0354475bd2c331fe8fd8a3690adc5c20..2b17ad5b4b32d27277a115de4cd2fd7834f7769d 100644 (file)
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -50,6 +50,7 @@
 #include <asm/pgtable.h>
 #include <asm/uaccess.h>
 #include <asm/tlb.h>
+#include <asm/e820.h>
 
 #include <asm/xen/hypervisor.h>
 #include <asm/xen/hypercall.h>
@@ -85,13 +86,6 @@ 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 */
@@ -126,7 +120,7 @@ static void scrub_page(struct page *page)
 }
 
 /* balloon_append: add the given page to the balloon. */
-static void balloon_append(struct page *page)
+static void __balloon_append(struct page *page)
 {
        /* Lowmem is re-populated first, so highmem pages go at list tail. */
        if (PageHighMem(page)) {
@@ -137,7 +131,11 @@ static void balloon_append(struct page *page)
                list_add(&page->lru, &ballooned_pages);
                balloon_stats.balloon_low++;
        }
+}
 
+static void balloon_append(struct page *page)
+{
+       __balloon_append(page);
        totalram_pages--;
 }
 
@@ -198,7 +196,7 @@ static unsigned long current_target(void)
 
 static int increase_reservation(unsigned long nr_pages)
 {
-       unsigned long  pfn, i, flags;
+       unsigned long  pfn, i;
        struct page   *page;
        long           rc;
        struct xen_memory_reservation reservation = {
@@ -210,8 +208,6 @@ 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);
-
        page = balloon_first_page();
        for (i = 0; i < nr_pages; i++) {
                BUG_ON(page == NULL);
@@ -254,14 +250,12 @@ static int increase_reservation(unsigned long nr_pages)
        balloon_stats.current_pages += rc;
 
  out:
-       spin_unlock_irqrestore(&balloon_lock, flags);
-
        return rc < 0 ? rc : rc != nr_pages;
 }
 
 static int decrease_reservation(unsigned long nr_pages)
 {
-       unsigned long  pfn, i, flags;
+       unsigned long  pfn, i;
        struct page   *page;
        int            need_sleep = 0;
        int ret;
@@ -299,8 +293,6 @@ static int decrease_reservation(unsigned long nr_pages)
        kmap_flush_unused();
        flush_tlb_all();
 
-       spin_lock_irqsave(&balloon_lock, flags);
-
        /* No more mappings: invalidate P2M and add to balloon. */
        for (i = 0; i < nr_pages; i++) {
                pfn = mfn_to_pfn(frame_list[i]);
@@ -315,8 +307,6 @@ static int decrease_reservation(unsigned long nr_pages)
 
        balloon_stats.current_pages -= nr_pages;
 
-       spin_unlock_irqrestore(&balloon_lock, flags);
-
        return need_sleep;
 }
 
@@ -402,7 +392,7 @@ static struct notifier_block xenstore_notifier;
 
 static int __init balloon_init(void)
 {
-       unsigned long pfn;
+       unsigned long pfn, extra_pfn_end;
        struct page *page;
 
        if (!xen_pv_domain())
@@ -423,10 +413,15 @@ static int __init balloon_init(void)
        register_balloon(&balloon_sysdev);
 
        /* Initialise the balloon with excess memory space. */
-       for (pfn = xen_start_info->nr_pages; pfn < max_pfn; pfn++) {
+       extra_pfn_end = min(e820_end_of_ram_pfn(),
+                           (unsigned long)PFN_DOWN(xen_extra_mem_start + xen_extra_mem_size));
+       for (pfn = PFN_UP(xen_extra_mem_start);
+            pfn < extra_pfn_end;
+            pfn++) {
                page = pfn_to_page(pfn);
-               if (!PageReserved(page))
-                       balloon_append(page);
+               /* totalram_pages doesn't include the boot-time
+                  balloon extension, so don't subtract from it. */
+               __balloon_append(page);
        }
 
        target_watch.callback = watch_target;