Nested Virtualization core implementation

Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
Acked-by: Tim Deegan <Tim.Deegan@citrix.com>
Committed-by: Tim Deegan <Tim.Deegan@citrix.com>

xen/arch/x86/hvm/Makefile

@@ -10,6 +10,7 @@ obj-y += intercept.o
 obj-y += io.o
 obj-y += irq.o
 obj-y += mtrr.o
+obj-y += nestedhvm.o
 obj-y += pmtimer.o
 obj-y += quirks.o
 obj-y += rtc.o

xen/arch/x86/hvm/nestedhvm.c

@@ -0,0 +1,177 @@
+/*
+ * Nested HVM
+ * Copyright (c) 2011, Advanced Micro Devices, Inc.
+ * Author: Christoph Egger <Christoph.Egger@amd.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include <asm/msr.h>
+#include <asm/hvm/support.h>	/* for HVM_DELIVER_NO_ERROR_CODE */
+#include <asm/hvm/hvm.h>
+#include <asm/hvm/nestedhvm.h>
+#include <asm/event.h>  /* for local_event_delivery_(en|dis)able */
+#include <asm/paging.h> /* for paging_mode_hap() */
+
+
+/* Nested HVM on/off per domain */
+bool_t
+nestedhvm_enabled(struct domain *d)
+{
+    bool_t enabled;
+
+    enabled = !!(d->arch.hvm_domain.params[HVM_PARAM_NESTEDHVM]);
+    /* sanity check */
+    BUG_ON(enabled && !is_hvm_domain(d));
+
+    if (!is_hvm_domain(d))
+        return 0;
+
+    return enabled;
+}
+
+/* Nested VCPU */
+bool_t
+nestedhvm_vcpu_in_guestmode(struct vcpu *v)
+{
+    return vcpu_nestedhvm(v).nv_guestmode;
+}
+
+void
+nestedhvm_vcpu_reset(struct vcpu *v)
+{
+    struct nestedvcpu *nv = &vcpu_nestedhvm(v);
+
+    nv->nv_vmentry_pending = 0;
+    nv->nv_vmexit_pending = 0;
+    nv->nv_vmswitch_in_progress = 0;
+    nv->nv_ioport80 = 0;
+    nv->nv_ioportED = 0;
+
+    if (nv->nv_vvmcx)
+        hvm_unmap_guest_frame(nv->nv_vvmcx);
+    nv->nv_vvmcx = NULL;
+    nv->nv_vvmcxaddr = VMCX_EADDR;
+    nv->nv_flushp2m = 0;
+    nv->nv_p2m = NULL;
+
+    nhvm_vcpu_reset(v);
+
+    /* vcpu is in host mode */
+    nestedhvm_vcpu_exit_guestmode(v);
+}
+
+int
+nestedhvm_vcpu_initialise(struct vcpu *v)
+{
+    int rc;
+
+    rc = nhvm_vcpu_initialise(v); 
+    if (rc) {
+        nhvm_vcpu_destroy(v);
+        return rc;
+    }
+
+    nestedhvm_vcpu_reset(v);
+    return 0;
+}
+
+int
+nestedhvm_vcpu_destroy(struct vcpu *v)
+{
+    if (!nestedhvm_enabled(v->domain))
+        return 0;
+
+    return nhvm_vcpu_destroy(v);
+}
+
+/* Common shadow IO Permission bitmap */
+
+/* There four global patterns of io bitmap each guest can
+ * choose depending on interception of io port 0x80 and/or
+ * 0xED (shown in table below).
+ * The users of the bitmap patterns are in SVM/VMX specific code.
+ *
+ * bitmap        port 0x80  port 0xed
+ * hvm_io_bitmap cleared    cleared
+ * iomap[0]      cleared    set
+ * iomap[1]      set        cleared
+ * iomap[2]      set        set
+ */
+
+/* same format and size as hvm_io_bitmap */
+#define IOBITMAP_SIZE		3*PAGE_SIZE/BYTES_PER_LONG
+/* same format as hvm_io_bitmap */
+#define IOBITMAP_VMX_SIZE	2*PAGE_SIZE/BYTES_PER_LONG
+
+static unsigned long *shadow_io_bitmap[3];
+
+void
+nestedhvm_setup(void)
+{
+    /* shadow_io_bitmaps can't be declared static because
+     *   they must fulfill hw requirements (page aligned section)
+     *   and doing so triggers the ASSERT(va >= XEN_VIRT_START)
+     *   in __virt_to_maddr()
+     *
+     * So as a compromise pre-allocate them when xen boots.
+     * This function must be called from within start_xen() when
+     * it is valid to use _xmalloc()
+     */
+
+    /* shadow I/O permission bitmaps */
+    if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) {
+        /* Same format as hvm_io_bitmap */
+        shadow_io_bitmap[0] = _xmalloc(IOBITMAP_VMX_SIZE, PAGE_SIZE);
+        shadow_io_bitmap[1] = _xmalloc(IOBITMAP_VMX_SIZE, PAGE_SIZE);
+        shadow_io_bitmap[2] = _xmalloc(IOBITMAP_VMX_SIZE, PAGE_SIZE);
+        memset(shadow_io_bitmap[0], ~0U, IOBITMAP_VMX_SIZE);
+        memset(shadow_io_bitmap[1], ~0U, IOBITMAP_VMX_SIZE);
+        memset(shadow_io_bitmap[2], ~0U, IOBITMAP_VMX_SIZE);
+    } else {
+        /* Same size and format as hvm_io_bitmap */
+        shadow_io_bitmap[0] = _xmalloc(IOBITMAP_SIZE, PAGE_SIZE);
+        shadow_io_bitmap[1] = _xmalloc(IOBITMAP_SIZE, PAGE_SIZE);
+        shadow_io_bitmap[2] = _xmalloc(IOBITMAP_SIZE, PAGE_SIZE);
+        memset(shadow_io_bitmap[0], ~0U, IOBITMAP_SIZE);
+        memset(shadow_io_bitmap[1], ~0U, IOBITMAP_SIZE);
+        memset(shadow_io_bitmap[2], ~0U, IOBITMAP_SIZE);
+    }
+
+    __clear_bit(0x80, shadow_io_bitmap[0]);
+    __clear_bit(0xed, shadow_io_bitmap[1]);
+}
+
+unsigned long *
+nestedhvm_vcpu_iomap_get(bool_t port_80, bool_t port_ed)
+{
+    int i;
+    extern int hvm_port80_allowed;
+
+    if (!hvm_port80_allowed)
+        port_80 = 1;
+
+    if (port_80 == 0) {
+        if (port_ed == 0)
+            return hvm_io_bitmap;
+        i = 0;
+    } else {
+        if (port_ed == 0)
+            i = 1;
+        else
+            i = 2;
+    }
+
+    return shadow_io_bitmap[i];
+}

xen/arch/x86/setup.c

@@ -1260,6 +1260,8 @@ void __init __start_xen(unsigned long mbi_p)
 
     if ( opt_watchdog ) 
         watchdog_setup();
+
+    nestedhvm_setup();
     
     if ( !tboot_protect_mem_regions() )
         panic("Could not protect TXT memory regions\n");

xen/include/asm-x86/hvm/nestedhvm.h

@@ -0,0 +1,63 @@
+/*
+ * Nested HVM
+ * Copyright (c) 2011, Advanced Micro Devices, Inc.
+ * Author: Christoph Egger <Christoph.Egger@amd.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#ifndef _HVM_NESTEDHVM_H
+#define _HVM_NESTEDHVM_H
+
+#include <xen/types.h>         /* for uintNN_t */
+#include <xen/sched.h>         /* for struct vcpu, struct domain */
+#include <asm/hvm/vcpu.h>      /* for vcpu_nestedhvm */
+
+enum nestedhvm_vmexits {
+    NESTEDHVM_VMEXIT_ERROR = 0, /* inject VMEXIT w/ invalid VMCB */
+    NESTEDHVM_VMEXIT_FATALERROR = 1, /* crash first level guest */
+    NESTEDHVM_VMEXIT_HOST = 2,  /* exit handled on host level */
+    NESTEDHVM_VMEXIT_CONTINUE = 3, /* further handling */
+    NESTEDHVM_VMEXIT_INJECT = 4, /* inject VMEXIT */
+    NESTEDHVM_VMEXIT_DONE = 5, /* VMEXIT handled */
+};
+
+/* Nested HVM on/off per domain */
+bool_t nestedhvm_enabled(struct domain *d);
+
+/* Nested VCPU */
+int nestedhvm_vcpu_initialise(struct vcpu *v);
+int nestedhvm_vcpu_destroy(struct vcpu *v);
+void nestedhvm_vcpu_reset(struct vcpu *v);
+bool_t nestedhvm_vcpu_in_guestmode(struct vcpu *v);
+#define nestedhvm_vcpu_enter_guestmode(v) \
+    vcpu_nestedhvm(v).nv_guestmode = 1
+#define nestedhvm_vcpu_exit_guestmode(v)  \
+    vcpu_nestedhvm(v).nv_guestmode = 0
+
+/* Nested paging */
+#define NESTEDHVM_PAGEFAULT_DONE   0
+#define NESTEDHVM_PAGEFAULT_INJECT 1
+#define NESTEDHVM_PAGEFAULT_ERROR  2
+int nestedhvm_hap_nested_page_fault(struct vcpu *v, paddr_t L2_gpa);
+
+/* IO permission map */
+unsigned long *nestedhvm_vcpu_iomap_get(bool_t ioport_80, bool_t ioport_ed);
+
+/* Misc */
+#define nestedhvm_paging_mode_hap(v) (!!nhvm_vmcx_hap_enabled(v))
+#define nestedhvm_vmswitch_in_progress(v)   \
+    (!!vcpu_nestedhvm((v)).nv_vmswitch_in_progress)
+
+#endif /* _HVM_NESTEDHVM_H */

xen/include/asm-x86/setup.h

@@ -23,6 +23,7 @@ int transmeta_init_cpu(void);
 void numa_initmem_init(unsigned long start_pfn, unsigned long end_pfn);
 void arch_init_memory(void);
 void subarch_init_memory(void);
+void nestedhvm_setup(void);
 
 void init_IRQ(void);
 void vesa_init(void);