Re: [PATCH 6/8] libxl: allow a generation ID to be specified at domain creation

[Hongyang Yang <yanghy@cn.fujitsu.com>]

Hi David,

there are 2 lines that have whitespace.

Applying: libxl: allow a generation ID to be specified at domain creation
/media/sda5/work/remus/.git/rebase-apply/patch:56: trailing whitespace.
     if (info->type == LIBXL_DOMAIN_TYPE_HVM
/media/sda5/work/remus/.git/rebase-apply/patch:101: trailing whitespace.
  *
warning: 2 lines add whitespace errors.

On 06/12/2014 11:04 PM, David Vrabel wrote:
> Toolstacks may specify a VM generation ID using the u.hvm.ms_vm_genid
> field in the libxl_domain_build_info structure, when creating a
> domain.
>
> The toolstack is responsible for providing the correct generation ID
> according to the Microsoft specification (e.g., generating new random
> ones with libxl_ms_vm_genid_generate() as appropriate when restoring).
>
> Although the specification requires that a ACPI Notify event is raised
> if the generation ID is changed, the generation ID is never changed
> when the domain is in a state to receive such an event (it's either
> newly created or suspended).
>
> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
> ---
>   tools/libxl/Makefile         |    1 +
>   tools/libxl/libxl.h          |    7 +++
>   tools/libxl/libxl_dom.c      |   10 ++++
>   tools/libxl/libxl_genid.c    |  104 ++++++++++++++++++++++++++++++++++++++++++
>   tools/libxl/libxl_internal.h |    4 ++
>   tools/libxl/libxl_types.idl  |    2 +
>   6 files changed, 128 insertions(+)
>   create mode 100644 tools/libxl/libxl_genid.c
>
> diff --git a/tools/libxl/Makefile b/tools/libxl/Makefile
> index 4cfa275..6499aa7 100644
> --- a/tools/libxl/Makefile
> +++ b/tools/libxl/Makefile
> @@ -77,6 +77,7 @@ LIBXL_OBJS = flexarray.o libxl.o libxl_create.o libxl_dm.o libxl_pci.o \
>   			libxl_json.o libxl_aoutils.o libxl_numa.o \
>   			libxl_save_callout.o _libxl_save_msgs_callout.o \
>   			libxl_qmp.o libxl_event.o libxl_fork.o $(LIBXL_OBJS-y)
> +LIBXL_OBJS += libxl_genid.o
>   LIBXL_OBJS += _libxl_types.o libxl_flask.o _libxl_types_internal.o
>
>   LIBXL_TESTS += timedereg
> diff --git a/tools/libxl/libxl.h b/tools/libxl/libxl.h
> index 17b8a7b..ab2f66a 100644
> --- a/tools/libxl/libxl.h
> +++ b/tools/libxl/libxl.h
> @@ -104,6 +104,11 @@
>   #define LIBXL_HAVE_BUILDINFO_EVENT_CHANNELS 1
>
>   /*
> + * libxl_domain_build_info has the u.hvm.ms_vm_genid field.
> + */
> +#define LIBXL_HAVE_BUILDINFO_HVM_MS_VM_GENID 1
> +
> +/*
>    * LIBXL_HAVE_DEVICE_DISK_DIRECT_IO_SAFE indicates that a
>    * 'direct_io_safe' field (of boolean type) is present in
>    * libxl_device_disk.
> @@ -1189,6 +1194,8 @@ int libxl_flask_getenforce(libxl_ctx *ctx);
>   int libxl_flask_setenforce(libxl_ctx *ctx, int mode);
>   int libxl_flask_loadpolicy(libxl_ctx *ctx, void *policy, uint32_t size);
>
> +int libxl_ms_vm_genid_generate(libxl_ctx *ctx, libxl_uuid *uuid);
> +
>   /* misc */
>
>   /* Each of these sets or clears the flag according to whether the
> diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c
> index 8485488..21ce07f 100644
> --- a/tools/libxl/libxl_dom.c
> +++ b/tools/libxl/libxl_dom.c
> @@ -314,6 +314,16 @@ int libxl__build_post(libxl__gc *gc, uint32_t domid,
>       if (info->cpuid != NULL)
>           libxl_cpuid_set(ctx, domid, info->cpuid);
>
> +    if (info->type == LIBXL_DOMAIN_TYPE_HVM
> +        && !libxl_uuid_is_nil(&info->u.hvm.ms_vm_genid)) {
> +        rc = libxl__ms_vm_genid_set(gc, domid,
> +                                    &info->u.hvm.ms_vm_genid);
> +        if (rc) {
> +            LOG(ERROR, "Failed to set VM Generation ID");
> +            return rc;
> +        }
> +    }
> +
>       ents = libxl__calloc(gc, 12 + (info->max_vcpus * 2) + 2, sizeof(char *));
>       ents[0] = "memory/static-max";
>       ents[1] = GCSPRINTF("%"PRId64, info->max_memkb);
> diff --git a/tools/libxl/libxl_genid.c b/tools/libxl/libxl_genid.c
> new file mode 100644
> index 0000000..565ed00
> --- /dev/null
> +++ b/tools/libxl/libxl_genid.c
> @@ -0,0 +1,104 @@
> +/*
> + * Copyright (C) 2014 Citrix Systems R&D Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU Lesser General Public License as published
> + * by the Free Software Foundation; version 2.1 only. with the special
> + * exception on linking described in file LICENSE.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU Lesser General Public License for more details.
> + */
> +
> +#include "libxl_osdeps.h" /* must come before any other headers */
> +
> +#include "libxl_internal.h"
> +
> +#include <xenctrl.h>
> +#include <xen/hvm/params.h>
> +
> +/*
> + * Generate a random VM generation ID.
> + *
> + * This is similar to libxl_uuid_generate() except that all bits are
> + * random, as required by the specification.
> + *
> + * Returns ERROR_FAIL if a suitable source of random numbers is not
> + * available.
> + *
> + * See Microsoft's "Virtual Machine Generation ID" specification for
> + * further details, including when a new generation ID is required.
> + *
> + *   http://www.microsoft.com/en-us/download/details.aspx?id=30707
> + */
> +int libxl_ms_vm_genid_generate(libxl_ctx *ctx, libxl_uuid *uuid)
> +{
> +    GC_INIT(ctx);
> +    int ret;
> +
> +    ret = libxl__random_bytes(gc, libxl_uuid_bytearray(uuid), 16);
> +
> +    GC_FREE;
> +    return ret;
> +}
> +
> +int libxl__ms_vm_genid_set(libxl__gc *gc, uint32_t domid,
> +                           const libxl_uuid *uuid)
> +{
> +    libxl_ctx *ctx = libxl__gc_owner(gc);
> +    const char *dom_path;
> +    uint64_t genid[2];
> +    uint64_t paddr = 0;
> +    int rc;
> +
> +    memcpy(genid, libxl_uuid_bytearray_const(uuid), 16);
> +
> +    /*
> +     * Set the "platform/generation-id" XenStore key to pass the ID to
> +     * hvmloader.
> +     */
> +    dom_path = libxl__xs_get_dompath(gc, domid);
> +    if (!dom_path) {
> +        rc = ERROR_FAIL;
> +        goto out;
> +    }
> +    rc = libxl__xs_write(gc, XBT_NULL,
> +                         GCSPRINTF("%s/platform/generation-id", dom_path),
> +                         "%"PRIu64 ":%" PRIu64, genid[0], genid[1]);
> +    if (rc < 0)
> +        goto out;
> +
> +    /*
> +     * Update the ID in guest memory (if available).
> +     */
> +    xc_get_hvm_param(ctx->xch, domid, HVM_PARAM_VM_GENERATION_ID_ADDR, &paddr);
> +    if (paddr) {
> +        void *vaddr;
> +
> +        vaddr = xc_map_foreign_range(ctx->xch, domid, XC_PAGE_SIZE,
> +                                     PROT_READ | PROT_WRITE,
> +                                     paddr >> XC_PAGE_SHIFT);
> +        if (vaddr == NULL) {
> +            rc = ERROR_FAIL;
> +            goto out;
> +        }
> +        memcpy(vaddr + (paddr & ~XC_PAGE_MASK), genid, 2 * sizeof(*genid));
> +        munmap(vaddr, XC_PAGE_SIZE);
> +
> +        /*
> +         * The spec requires an ACPI Notify event is injected into the
> +         * guest when the generation ID is changed.
> +         *
> +         * This is only called for domains that are suspended or newly
> +         * created and they won't be in a state to receive such an
> +         * event.
> +         */
> +    }
> +
> +    rc = 0;
> +
> +  out:
> +    return rc;
> +}
> diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
> index d4f32a9..fa9a150 100644
> --- a/tools/libxl/libxl_internal.h
> +++ b/tools/libxl/libxl_internal.h
> @@ -3086,6 +3086,10 @@ void libxl__numa_candidate_put_nodemap(libxl__gc *gc,
>       libxl_bitmap_copy(CTX, &cndt->nodemap, nodemap);
>   }
>
> +_hidden int libxl__ms_vm_genid_set(libxl__gc *gc, uint32_t domid,
> +                                   const libxl_uuid *uuid);
> +
> +
>   /* Som handy macros for defbool type. */
>   #define LIBXL__DEFBOOL_DEFAULT     (0)
>   #define LIBXL__DEFBOOL_FALSE       (-1)
> diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
> index f0f6e34..1c5e687 100644
> --- a/tools/libxl/libxl_types.idl
> +++ b/tools/libxl/libxl_types.idl
> @@ -371,6 +371,8 @@ libxl_domain_build_info = Struct("domain_build_info",[
>                                          ("xen_platform_pci", libxl_defbool),
>                                          ("usbdevice_list",   libxl_string_list),
>                                          ("vendor_device",    libxl_vendor_device),
> +                                       # See libxl_ms_vm_genid_generate()
> +                                       ("ms_vm_genid",      libxl_uuid),
>                                          ])),
>                    ("pv", Struct(None, [("kernel", string),
>                                         ("slack_memkb", MemKB),
>

-- 
Thanks,
Yang.