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-rw-r--r--arch/x86/xen/setup.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index ad0047f47cd4..328b00305426 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -20,6 +20,7 @@
#include <xen/page.h>
#include <xen/interface/callback.h>
#include <xen/interface/physdev.h>
+#include <xen/interface/memory.h>
#include <xen/features.h>
#include "xen-ops.h"
@@ -32,6 +33,73 @@ extern void xen_sysenter_target(void);
extern void xen_syscall_target(void);
extern void xen_syscall32_target(void);
+static unsigned long __init xen_release_chunk(phys_addr_t start_addr,
+ phys_addr_t end_addr)
+{
+ struct xen_memory_reservation reservation = {
+ .address_bits = 0,
+ .extent_order = 0,
+ .domid = DOMID_SELF
+ };
+ unsigned long start, end;
+ unsigned long len = 0;
+ unsigned long pfn;
+ int ret;
+
+ start = PFN_UP(start_addr);
+ end = PFN_DOWN(end_addr);
+
+ if (end <= start)
+ return 0;
+
+ printk(KERN_INFO "xen_release_chunk: looking at area pfn %lx-%lx: ",
+ start, end);
+ for(pfn = start; pfn < end; pfn++) {
+ unsigned long mfn = pfn_to_mfn(pfn);
+
+ /* Make sure pfn exists to start with */
+ if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn)
+ continue;
+
+ set_xen_guest_handle(reservation.extent_start, &mfn);
+ reservation.nr_extents = 1;
+
+ ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
+ &reservation);
+ WARN(ret != 1, "Failed to release memory %lx-%lx err=%d\n",
+ start, end, ret);
+ if (ret == 1) {
+ set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
+ len++;
+ }
+ }
+ printk(KERN_CONT "%ld pages freed\n", len);
+
+ return len;
+}
+
+static unsigned long __init xen_return_unused_memory(unsigned long max_pfn,
+ const struct e820map *e820)
+{
+ phys_addr_t max_addr = PFN_PHYS(max_pfn);
+ phys_addr_t last_end = 0;
+ unsigned long released = 0;
+ int i;
+
+ for (i = 0; i < e820->nr_map && last_end < max_addr; i++) {
+ phys_addr_t end = e820->map[i].addr;
+ end = min(max_addr, end);
+
+ released += xen_release_chunk(last_end, end);
+ last_end = e820->map[i].addr + e820->map[i].size;
+ }
+
+ if (last_end < max_addr)
+ released += xen_release_chunk(last_end, max_addr);
+
+ printk(KERN_INFO "released %ld pages of unused memory\n", released);
+ return released;
+}
/**
* machine_specific_memory_setup - Hook for machine specific memory setup.
@@ -67,6 +135,8 @@ char * __init xen_memory_setup(void)
sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ xen_return_unused_memory(xen_start_info->nr_pages, &e820);
+
return "Xen";
}
@@ -156,6 +226,8 @@ void __init xen_arch_setup(void)
struct physdev_set_iopl set_iopl;
int rc;
+ xen_panic_handler_init();
+
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
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