On Sun, 30 Oct 2016 23:25:05 +0200
"Michael S. Tsirkin" <m...@redhat.com> wrote:
> From: Xiao Guangrong <guangrong.x...@linux.intel.com>
>
> The buffer is used to save the FIT info for all the presented nvdimm
> devices which is updated after the nvdimm device is plugged or
> unplugged. In the later patch, it will be used to construct NVDIMM
> ACPI _FIT method which reflects the presented nvdimm devices after
> nvdimm hotplug
>
> As FIT buffer can not completely mapped into guest address space,
> OSPM will exit to QEMU multiple times, however, there is the race
> condition - FIT may be changed during these multiple exits, so that
> some rules are introduced:
> 1) the user should hold the @lock to access the buffer and
> 2) mark @dirty whenever the buffer is updated.
>
> @dirty is cleared for the first time OSPM gets fit buffer, if
> dirty is detected in the later access, OSPM will restart the
> access
>
> As fit should be updated after nvdimm device is successfully realized
> so that a new hotplug callback, post_hotplug, is introduced
>
> Signed-off-by: Xiao Guangrong <guangrong.x...@linux.intel.com>
> Reviewed-by: Michael S. Tsirkin <m...@redhat.com>
> Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
> ---
> include/hw/hotplug.h | 10 +++++++++
> include/hw/mem/nvdimm.h | 26 +++++++++++++++++++++-
> hw/acpi/nvdimm.c | 59
> +++++++++++++++++++++++++++++++++++--------------
> hw/core/hotplug.c | 11 +++++++++
> hw/core/qdev.c | 20 +++++++++++++----
> hw/i386/acpi-build.c | 2 +-
> hw/i386/pc.c | 19 ++++++++++++++++
> 7 files changed, 124 insertions(+), 23 deletions(-)
>
> diff --git a/include/hw/hotplug.h b/include/hw/hotplug.h
> index c0db869..10ca5b6 100644
> --- a/include/hw/hotplug.h
> +++ b/include/hw/hotplug.h
> @@ -47,6 +47,7 @@ typedef void (*hotplug_fn)(HotplugHandler *plug_handler,
> * @parent: Opaque parent interface.
> * @pre_plug: pre plug callback called at start of device.realize(true)
> * @plug: plug callback called at end of device.realize(true).
> + * @post_pug: post plug callback called after device is successfully plugged.
this doesn't seem to be necessary,
why hotplug_handler_plug() isn't sufficient?
> * @unplug_request: unplug request callback.
> * Used as a means to initiate device unplug for devices
> that
> * require asynchronous unplug handling.
> @@ -61,6 +62,7 @@ typedef struct HotplugHandlerClass {
> /* <public> */
> hotplug_fn pre_plug;
> hotplug_fn plug;
> + hotplug_fn post_plug;
> hotplug_fn unplug_request;
> hotplug_fn unplug;
> } HotplugHandlerClass;
> @@ -83,6 +85,14 @@ void hotplug_handler_pre_plug(HotplugHandler *plug_handler,
> DeviceState *plugged_dev,
> Error **errp);
>
> +/**
> + * hotplug_handler_post_plug:
> + *
> + * Call #HotplugHandlerClass.post_plug callback of @plug_handler.
> + */
> +void hotplug_handler_post_plug(HotplugHandler *plug_handler,
> + DeviceState *plugged_dev,
> + Error **errp);
>
> /**
> * hotplug_handler_unplug_request:
> diff --git a/include/hw/mem/nvdimm.h b/include/hw/mem/nvdimm.h
> index 63a2b20..33cd421 100644
> --- a/include/hw/mem/nvdimm.h
> +++ b/include/hw/mem/nvdimm.h
> @@ -98,12 +98,35 @@ typedef struct NVDIMMClass NVDIMMClass;
> #define NVDIMM_ACPI_IO_BASE 0x0a18
> #define NVDIMM_ACPI_IO_LEN 4
>
> +/*
> + * The buffer, @fit, saves the FIT info for all the presented NVDIMM
> + * devices which is updated after the NVDIMM device is plugged or
> + * unplugged.
> + *
> + * Rules to use the buffer:
> + * 1) the user should hold the @lock to access the buffer.
> + * 2) mark @dirty whenever the buffer is updated.
> + *
> + * These rules preserve NVDIMM ACPI _FIT method to read incomplete
> + * or obsolete fit info if fit update happens during multiple RFIT
> + * calls.
> + */
> +struct NvdimmFitBuffer {
> + QemuMutex lock;
> + GArray *fit;
> + bool dirty;
> +};
> +typedef struct NvdimmFitBuffer NvdimmFitBuffer;
> +
> struct AcpiNVDIMMState {
> /* detect if NVDIMM support is enabled. */
> bool is_enabled;
>
> /* the data of the fw_cfg file NVDIMM_DSM_MEM_FILE. */
> GArray *dsm_mem;
> +
> + NvdimmFitBuffer fit_buf;
> +
> /* the IO region used by OSPM to transfer control to QEMU. */
> MemoryRegion io_mr;
> };
> @@ -112,6 +135,7 @@ typedef struct AcpiNVDIMMState AcpiNVDIMMState;
> void nvdimm_init_acpi_state(AcpiNVDIMMState *state, MemoryRegion *io,
> FWCfgState *fw_cfg, Object *owner);
> void nvdimm_build_acpi(GArray *table_offsets, GArray *table_data,
> - BIOSLinker *linker, GArray *dsm_dma_arrea,
> + BIOSLinker *linker, AcpiNVDIMMState *state,
> uint32_t ram_slots);
> +void nvdimm_acpi_hotplug(AcpiNVDIMMState *state);
> #endif
> diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
> index b8a2e62..5f728a6 100644
> --- a/hw/acpi/nvdimm.c
> +++ b/hw/acpi/nvdimm.c
> @@ -348,8 +348,9 @@ static void nvdimm_build_structure_dcr(GArray
> *structures, DeviceState *dev)
> (DSM) in DSM Spec Rev1.*/);
> }
>
> -static GArray *nvdimm_build_device_structure(GSList *device_list)
> +static GArray *nvdimm_build_device_structure(void)
> {
> + GSList *device_list = nvdimm_get_plugged_device_list();
> GArray *structures = g_array_new(false, true /* clear */, 1);
>
> for (; device_list; device_list = device_list->next) {
> @@ -367,28 +368,58 @@ static GArray *nvdimm_build_device_structure(GSList
> *device_list)
> /* build NVDIMM Control Region Structure. */
> nvdimm_build_structure_dcr(structures, dev);
> }
> + g_slist_free(device_list);
>
> return structures;
> }
>
> -static void nvdimm_build_nfit(GSList *device_list, GArray *table_offsets,
> +static void nvdimm_init_fit_buffer(NvdimmFitBuffer *fit_buf)
> +{
> + qemu_mutex_init(&fit_buf->lock);
> + fit_buf->fit = g_array_new(false, true /* clear */, 1);
> +}
> +
> +static void nvdimm_build_fit_buffer(NvdimmFitBuffer *fit_buf)
> +{
> + qemu_mutex_lock(&fit_buf->lock);
> + g_array_free(fit_buf->fit, true);
> + fit_buf->fit = nvdimm_build_device_structure();
> + fit_buf->dirty = true;
> + qemu_mutex_unlock(&fit_buf->lock);
> +}
> +
> +void nvdimm_acpi_hotplug(AcpiNVDIMMState *state)
> +{
> + nvdimm_build_fit_buffer(&state->fit_buf);
> +}
> +
> +static void nvdimm_build_nfit(AcpiNVDIMMState *state, GArray *table_offsets,
> GArray *table_data, BIOSLinker *linker)
> {
> - GArray *structures = nvdimm_build_device_structure(device_list);
> + NvdimmFitBuffer *fit_buf = &state->fit_buf;
> unsigned int header;
>
> + qemu_mutex_lock(&fit_buf->lock);
> +
> + /* NVDIMM device is not plugged? */
> + if (!fit_buf->fit->len) {
> + goto exit;
> + }
> +
> acpi_add_table(table_offsets, table_data);
>
> /* NFIT header. */
> header = table_data->len;
> acpi_data_push(table_data, sizeof(NvdimmNfitHeader));
> /* NVDIMM device structures. */
> - g_array_append_vals(table_data, structures->data, structures->len);
> + g_array_append_vals(table_data, fit_buf->fit->data, fit_buf->fit->len);
>
> build_header(linker, table_data,
> (void *)(table_data->data + header), "NFIT",
> - sizeof(NvdimmNfitHeader) + structures->len, 1, NULL, NULL);
> - g_array_free(structures, true);
> + sizeof(NvdimmNfitHeader) + fit_buf->fit->len, 1, NULL,
> NULL);
> +
> +exit:
> + qemu_mutex_unlock(&fit_buf->lock);
> }
>
> struct NvdimmDsmIn {
> @@ -771,6 +802,8 @@ void nvdimm_init_acpi_state(AcpiNVDIMMState *state,
> MemoryRegion *io,
> acpi_data_push(state->dsm_mem, sizeof(NvdimmDsmIn));
> fw_cfg_add_file(fw_cfg, NVDIMM_DSM_MEM_FILE, state->dsm_mem->data,
> state->dsm_mem->len);
> +
> + nvdimm_init_fit_buffer(&state->fit_buf);
> }
>
> #define NVDIMM_COMMON_DSM "NCAL"
> @@ -1045,25 +1078,17 @@ static void nvdimm_build_ssdt(GArray *table_offsets,
> GArray *table_data,
> }
>
> void nvdimm_build_acpi(GArray *table_offsets, GArray *table_data,
> - BIOSLinker *linker, GArray *dsm_dma_arrea,
> + BIOSLinker *linker, AcpiNVDIMMState *state,
> uint32_t ram_slots)
> {
> - GSList *device_list;
> -
> - device_list = nvdimm_get_plugged_device_list();
> -
> - /* NVDIMM device is plugged. */
> - if (device_list) {
> - nvdimm_build_nfit(device_list, table_offsets, table_data, linker);
> - g_slist_free(device_list);
> - }
> + nvdimm_build_nfit(state, table_offsets, table_data, linker);
>
> /*
> * NVDIMM device is allowed to be plugged only if there is available
> * slot.
> */
> if (ram_slots) {
> - nvdimm_build_ssdt(table_offsets, table_data, linker, dsm_dma_arrea,
> + nvdimm_build_ssdt(table_offsets, table_data, linker, state->dsm_mem,
> ram_slots);
> }
> }
> diff --git a/hw/core/hotplug.c b/hw/core/hotplug.c
> index 17ac986..ab34c19 100644
> --- a/hw/core/hotplug.c
> +++ b/hw/core/hotplug.c
> @@ -35,6 +35,17 @@ void hotplug_handler_plug(HotplugHandler *plug_handler,
> }
> }
>
> +void hotplug_handler_post_plug(HotplugHandler *plug_handler,
> + DeviceState *plugged_dev,
> + Error **errp)
> +{
> + HotplugHandlerClass *hdc = HOTPLUG_HANDLER_GET_CLASS(plug_handler);
> +
> + if (hdc->post_plug) {
> + hdc->post_plug(plug_handler, plugged_dev, errp);
> + }
> +}
> +
> void hotplug_handler_unplug_request(HotplugHandler *plug_handler,
> DeviceState *plugged_dev,
> Error **errp)
> diff --git a/hw/core/qdev.c b/hw/core/qdev.c
> index 5783442..d835e62 100644
> --- a/hw/core/qdev.c
> +++ b/hw/core/qdev.c
> @@ -945,10 +945,21 @@ static void device_set_realized(Object *obj, bool
> value, Error **errp)
> goto child_realize_fail;
> }
> }
> +
> if (dev->hotplugged) {
> device_reset(dev);
> }
> dev->pending_deleted_event = false;
> + dev->realized = value;
> +
> + if (hotplug_ctrl) {
> + hotplug_handler_post_plug(hotplug_ctrl, dev, &local_err);
> + }
> +
> + if (local_err != NULL) {
> + dev->realized = value;
> + goto post_realize_fail;
> + }
> } else if (!value && dev->realized) {
> Error **local_errp = NULL;
> QLIST_FOREACH(bus, &dev->child_bus, sibling) {
> @@ -965,13 +976,14 @@ static void device_set_realized(Object *obj, bool
> value, Error **errp)
> }
> dev->pending_deleted_event = true;
> DEVICE_LISTENER_CALL(unrealize, Reverse, dev);
> - }
>
> - if (local_err != NULL) {
> - goto fail;
> + if (local_err != NULL) {
> + goto fail;
> + }
> +
> + dev->realized = value;
> }
>
> - dev->realized = value;
> return;
>
> child_realize_fail:
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index cec4b4e..03a5386 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -2811,7 +2811,7 @@ void acpi_build(AcpiBuildTables *tables, MachineState
> *machine)
> }
> if (pcms->acpi_nvdimm_state.is_enabled) {
> nvdimm_build_acpi(table_offsets, tables_blob, tables->linker,
> - pcms->acpi_nvdimm_state.dsm_mem,
> machine->ram_slots);
> + &pcms->acpi_nvdimm_state, machine->ram_slots);
> }
>
> /* Add tables supplied by user (if any) */
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index f56ea0f..b395717 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1721,6 +1721,16 @@ out:
> error_propagate(errp, local_err);
> }
>
> +static void pc_dimm_post_plug(HotplugHandler *hotplug_dev,
> + DeviceState *dev, Error **errp)
> +{
> + PCMachineState *pcms = PC_MACHINE(hotplug_dev);
> +
> + if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
> + nvdimm_acpi_hotplug(&pcms->acpi_nvdimm_state);
> + }
> +}
> +
> static void pc_dimm_unplug_request(HotplugHandler *hotplug_dev,
> DeviceState *dev, Error **errp)
> {
> @@ -1986,6 +1996,14 @@ static void pc_machine_device_plug_cb(HotplugHandler
> *hotplug_dev,
> }
> }
>
> +static void pc_machine_device_post_plug_cb(HotplugHandler *hotplug_dev,
> + DeviceState *dev, Error **errp)
> +{
> + if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
> + pc_dimm_post_plug(hotplug_dev, dev, errp);
> + }
> +}
> +
> static void pc_machine_device_unplug_request_cb(HotplugHandler *hotplug_dev,
> DeviceState *dev, Error
> **errp)
> {
> @@ -2290,6 +2308,7 @@ static void pc_machine_class_init(ObjectClass *oc, void
> *data)
> mc->reset = pc_machine_reset;
> hc->pre_plug = pc_machine_device_pre_plug_cb;
> hc->plug = pc_machine_device_plug_cb;
> + hc->post_plug = pc_machine_device_post_plug_cb;
> hc->unplug_request = pc_machine_device_unplug_request_cb;
> hc->unplug = pc_machine_device_unplug_cb;
> nc->nmi_monitor_handler = x86_nmi;
