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-rw-r--r--arch/x86/xen/enlighten.c150
1 files changed, 141 insertions, 9 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 30c6e986a6cd..53282dc7d5ac 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1,11 +1,10 @@
// SPDX-License-Identifier: GPL-2.0
-#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
-#include <linux/memblock.h>
-#endif
#include <linux/console.h>
#include <linux/cpu.h>
+#include <linux/instrumentation.h>
#include <linux/kexec.h>
+#include <linux/memblock.h>
#include <linux/slab.h>
#include <linux/panic_notifier.h>
@@ -22,20 +21,22 @@
#include <asm/setup.h>
#include "xen-ops.h"
-#include "smp.h"
-#include "pmu.h"
-EXPORT_SYMBOL_GPL(hypercall_page);
+DEFINE_STATIC_CALL(xen_hypercall, xen_hypercall_hvm);
+EXPORT_STATIC_CALL_TRAMP(xen_hypercall);
/*
* Pointer to the xen_vcpu_info structure or
* &HYPERVISOR_shared_info->vcpu_info[cpu]. See xen_hvm_init_shared_info
* and xen_vcpu_setup for details. By default it points to share_info->vcpu_info
* but during boot it is switched to point to xen_vcpu_info.
- * The pointer is used in __xen_evtchn_do_upcall to acknowledge pending events.
+ * The pointer is used in xen_evtchn_do_upcall to acknowledge pending events.
+ * Make sure that xen_vcpu_info doesn't cross a page boundary by making it
+ * cache-line aligned (the struct is guaranteed to have a size of 64 bytes,
+ * which matches the cache line size of 64-bit x86 processors).
*/
DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
-DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
+DEFINE_PER_CPU_ALIGNED(struct vcpu_info, xen_vcpu_info);
/* Linux <-> Xen vCPU id mapping */
DEFINE_PER_CPU(uint32_t, xen_vcpu_id);
@@ -51,7 +52,7 @@ EXPORT_SYMBOL_GPL(xen_start_info);
struct shared_info xen_dummy_shared_info;
-__read_mostly int xen_have_vector_callback;
+__read_mostly bool xen_have_vector_callback = true;
EXPORT_SYMBOL_GPL(xen_have_vector_callback);
/*
@@ -69,6 +70,65 @@ EXPORT_SYMBOL(xen_start_flags);
*/
struct shared_info *HYPERVISOR_shared_info = &xen_dummy_shared_info;
+/* Number of pages released from the initial allocation. */
+unsigned long xen_released_pages;
+
+static __ref void xen_get_vendor(void)
+{
+ init_cpu_devs();
+ cpu_detect(&boot_cpu_data);
+ get_cpu_vendor(&boot_cpu_data);
+}
+
+void xen_hypercall_setfunc(void)
+{
+ if (static_call_query(xen_hypercall) != xen_hypercall_hvm)
+ return;
+
+ if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+ boot_cpu_data.x86_vendor == X86_VENDOR_HYGON))
+ static_call_update(xen_hypercall, xen_hypercall_amd);
+ else
+ static_call_update(xen_hypercall, xen_hypercall_intel);
+}
+
+/*
+ * Evaluate processor vendor in order to select the correct hypercall
+ * function for HVM/PVH guests.
+ * Might be called very early in boot before vendor has been set by
+ * early_cpu_init().
+ */
+noinstr void *__xen_hypercall_setfunc(void)
+{
+ void (*func)(void);
+
+ /*
+ * Note that __xen_hypercall_setfunc() is noinstr only due to a nasty
+ * dependency chain: it is being called via the xen_hypercall static
+ * call when running as a PVH or HVM guest. Hypercalls need to be
+ * noinstr due to PV guests using hypercalls in noinstr code. So we
+ * can safely tag the function body as "instrumentation ok", since
+ * the PV guest requirement is not of interest here (xen_get_vendor()
+ * calls noinstr functions, and static_call_update_early() might do
+ * so, too).
+ */
+ instrumentation_begin();
+
+ xen_get_vendor();
+
+ if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+ boot_cpu_data.x86_vendor == X86_VENDOR_HYGON))
+ func = xen_hypercall_amd;
+ else
+ func = xen_hypercall_intel;
+
+ static_call_update_early(xen_hypercall, func);
+
+ instrumentation_end();
+
+ return func;
+}
+
static int xen_cpu_up_online(unsigned int cpu)
{
xen_init_lock_cpu(cpu);
@@ -160,6 +220,7 @@ void xen_vcpu_setup(int cpu)
int err;
struct vcpu_info *vcpup;
+ BUILD_BUG_ON(sizeof(*vcpup) > SMP_CACHE_BYTES);
BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
/*
@@ -346,3 +407,74 @@ void xen_arch_unregister_cpu(int num)
}
EXPORT_SYMBOL(xen_arch_unregister_cpu);
#endif
+
+/* Amount of extra memory space we add to the e820 ranges */
+struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
+
+void __init xen_add_extra_mem(unsigned long start_pfn, unsigned long n_pfns)
+{
+ unsigned int i;
+
+ /*
+ * No need to check for zero size, should happen rarely and will only
+ * write a new entry regarded to be unused due to zero size.
+ */
+ for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
+ /* Add new region. */
+ if (xen_extra_mem[i].n_pfns == 0) {
+ xen_extra_mem[i].start_pfn = start_pfn;
+ xen_extra_mem[i].n_pfns = n_pfns;
+ break;
+ }
+ /* Append to existing region. */
+ if (xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns ==
+ start_pfn) {
+ xen_extra_mem[i].n_pfns += n_pfns;
+ break;
+ }
+ }
+ if (i == XEN_EXTRA_MEM_MAX_REGIONS)
+ printk(KERN_WARNING "Warning: not enough extra memory regions\n");
+
+ memblock_reserve(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns));
+}
+
+#ifdef CONFIG_XEN_UNPOPULATED_ALLOC
+int __init arch_xen_unpopulated_init(struct resource **res)
+{
+ unsigned int i;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ /* Must be set strictly before calling xen_free_unpopulated_pages(). */
+ *res = &iomem_resource;
+
+ /*
+ * Initialize with pages from the extra memory regions (see
+ * arch/x86/xen/setup.c).
+ */
+ for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
+ unsigned int j;
+
+ for (j = 0; j < xen_extra_mem[i].n_pfns; j++) {
+ struct page *pg =
+ pfn_to_page(xen_extra_mem[i].start_pfn + j);
+
+ xen_free_unpopulated_pages(1, &pg);
+ }
+
+ /*
+ * Account for the region being in the physmap but unpopulated.
+ * The value in xen_released_pages is used by the balloon
+ * driver to know how much of the physmap is unpopulated and
+ * set an accurate initial memory target.
+ */
+ xen_released_pages += xen_extra_mem[i].n_pfns;
+ /* Zero so region is not also added to the balloon driver. */
+ xen_extra_mem[i].n_pfns = 0;
+ }
+
+ return 0;
+}
+#endif