Re: [Qemu-devel] [PATCH v5 4/5] nvdimm acpi: emulate dsm method

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Mar 02, 2016 at 07:50:40PM +0800, Xiao Guangrong wrote:
> Emulate dsm method after IO VM-exit
> 
> Currently, we only introduce the framework and no function is actually
> supported
> 
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> ---
>  hw/acpi/nvdimm.c        | 56 +++++++++++++++++++++++++++++++++++++++++++++++++
>  include/hw/mem/nvdimm.h |  8 +++++++
>  2 files changed, 64 insertions(+)
> 
> diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
> index 781f6c1..5a17ee2 100644
> --- a/hw/acpi/nvdimm.c
> +++ b/hw/acpi/nvdimm.c
> @@ -390,15 +390,71 @@ struct NvdimmDsmOut {
>  } QEMU_PACKED;
>  typedef struct NvdimmDsmOut NvdimmDsmOut;
>  
> +struct NvdimmDsmFunc0Out {
> +    /* the size of buffer filled by QEMU. */
> +     uint32_t len;
> +     uint32_t supported_func;
> +} QEMU_PACKED;
> +typedef struct NvdimmDsmFunc0Out NvdimmDsmFunc0Out;
> +
> +struct NvdimmDsmFuncNoPayloadOut {
> +    /* the size of buffer filled by QEMU. */
> +     uint32_t len;
> +     uint32_t func_ret_status;
> +} QEMU_PACKED;
> +typedef struct NvdimmDsmFuncNoPayloadOut NvdimmDsmFuncNoPayloadOut;
> +
>  static uint64_t
>  nvdimm_dsm_read(void *opaque, hwaddr addr, unsigned size)
>  {
> +    nvdimm_debug("BUG: we never read _DSM IO Port.\n");
>      return 0;
>  }
>  
>  static void
>  nvdimm_dsm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
>  {
> +    NvdimmDsmIn *in;
> +    hwaddr dsm_mem_addr = val;
> +
> +    nvdimm_debug("dsm memory address %#lx.\n", dsm_mem_addr);
> +
> +    /*
> +     * The DSM memory is mapped to guest address space so an evil guest
> +     * can change its content while we are doing DSM emulation. Avoid
> +     * this by copying DSM memory to QEMU local memory.
> +     */
> +    in = g_malloc(TARGET_PAGE_SIZE);
> +    cpu_physical_memory_read(dsm_mem_addr, in, TARGET_PAGE_SIZE);
> +
> +    le32_to_cpus(&in->revision);
> +    le32_to_cpus(&in->function);
> +    le32_to_cpus(&in->handle);
> +
> +    nvdimm_debug("Revision %#x Handler %#x Function %#x.\n", in->revision,
> +                 in->handle, in->function);
> +
> +    /*
> +     * function 0 is called to inquire what functions

which functions

> are supported by
> +     * OSPM
> +     */
> +    if (in->function == 0) {
> +        NvdimmDsmFunc0Out func0 = {
> +            .len = cpu_to_le32(sizeof(func0)),
> +             /* No function supported other than function 0 */
> +            .supported_func = cpu_to_le32(0),
> +        };
> +        cpu_physical_memory_write(dsm_mem_addr, &func0, sizeof func0);
> +    } else {
> +        /* No function except function 0 is supported yet. */
> +        NvdimmDsmFuncNoPayloadOut out = {
> +            .len = cpu_to_le32(sizeof(out)),
> +            .func_ret_status = cpu_to_le32(1)  /* Not Supported */,
> +        };
> +        cpu_physical_memory_write(dsm_mem_addr, &out, sizeof(out));
> +    }
> +
> +    g_free(in);
>  }
>  
>  static const MemoryRegionOps nvdimm_dsm_ops = {
> diff --git a/include/hw/mem/nvdimm.h b/include/hw/mem/nvdimm.h
> index 634c60b..aaa2608 100644
> --- a/include/hw/mem/nvdimm.h
> +++ b/include/hw/mem/nvdimm.h
> @@ -25,6 +25,14 @@
>  
>  #include "hw/mem/pc-dimm.h"
>  
> +#define NVDIMM_DEBUG 0
> +#define nvdimm_debug(fmt, ...)                                \
> +    do {                                                      \
> +        if (NVDIMM_DEBUG) {                                   \
> +            fprintf(stderr, "nvdimm: " fmt, ## __VA_ARGS__);  \
> +        }                                                     \
> +    } while (0)
> +
>  #define TYPE_NVDIMM             "nvdimm"
>  
>  #define NVDIMM_DSM_MEM_FILE     "etc/acpi/nvdimm-mem"
> -- 
> 1.8.3.1