Merge branch 'master' into csb1725

[mv-sheeva.git] / drivers / xen / balloon.c

diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 500290b150bb526cf27b9f5e82d9a08b160a2d91..43f9f02c7db0671668343fc19bed043fbbe61fad 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>
@@ -119,7 +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)) {
@@ -130,7 +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--;
 }
 
@@ -191,7 +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 = {
@@ -203,8 +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(&xen_reservation_lock, flags);
-
        page = balloon_first_page();
        for (i = 0; i < nr_pages; i++) {
                BUG_ON(page == NULL);
@@ -247,14 +250,12 @@ static int increase_reservation(unsigned long nr_pages)
        balloon_stats.current_pages += rc;
 
  out:
-       spin_unlock_irqrestore(&xen_reservation_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;
@@ -292,8 +293,6 @@ static int decrease_reservation(unsigned long nr_pages)
        kmap_flush_unused();
        flush_tlb_all();
 
-       spin_lock_irqsave(&xen_reservation_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]);
@@ -308,8 +307,6 @@ static int decrease_reservation(unsigned long nr_pages)
 
        balloon_stats.current_pages -= nr_pages;
 
-       spin_unlock_irqrestore(&xen_reservation_lock, flags);
-
        return need_sleep;
 }
 
@@ -395,7 +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())
@@ -415,11 +412,24 @@ 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++) {
+       /*
+        * Initialise the balloon with excess memory space.  We need
+        * to make sure we don't add memory which doesn't exist or
+        * logically exist.  The E820 map can be trimmed to be smaller
+        * than the amount of physical memory due to the mem= command
+        * line parameter.  And if this is a 32-bit non-HIGHMEM kernel
+        * on a system with memory which requires highmem to access,
+        * don't try to use it.
+        */
+       extra_pfn_end = min(min(max_pfn, 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;