aboutsummaryrefslogtreecommitdiff
path: root/drivers/xen/balloon.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/xen/balloon.c')
-rw-r--r--drivers/xen/balloon.c42
1 files changed, 26 insertions, 16 deletions
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 500290b150b..43f9f02c7db 100644
--- 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;