Re: [Qemu-devel] [Intel-gfx][RFC 9/9] drm/i915/gvt: Add support to VFIO region VFIO_PCI_DEVICE_STATE_REGION_INDEX

[Dr. David Alan Gilbert]

* Yulei Zhang (address@hidden) wrote:
> Add new VFIO region VFIO_PCI_DEVICE_STATE_REGION_INDEX support in vGPU, 
> through
> this new region it can fetch the status from mdev device for migration, on
> the target side it can retrieve the device status and reconfigure the device 
> to
> continue running after resume the guest.
> 
> Signed-off-by: Yulei Zhang <address@hidden>

This is a HUGE patch.
I can't really tell how it wires into the rest of migration.
It would probably be best to split it up into cunks
to make it easier to review.

Dave

> ---
>  drivers/gpu/drm/i915/gvt/Makefile  |   2 +-
>  drivers/gpu/drm/i915/gvt/gvt.c     |   1 +
>  drivers/gpu/drm/i915/gvt/gvt.h     |   5 +
>  drivers/gpu/drm/i915/gvt/kvmgt.c   |  19 +
>  drivers/gpu/drm/i915/gvt/migrate.c | 715 
> +++++++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/i915/gvt/migrate.h |  82 +++++
>  drivers/gpu/drm/i915/gvt/mmio.c    |  14 +
>  drivers/gpu/drm/i915/gvt/mmio.h    |   1 +
>  include/uapi/linux/vfio.h          |   3 +-
>  9 files changed, 840 insertions(+), 2 deletions(-)
>  create mode 100644 drivers/gpu/drm/i915/gvt/migrate.c
>  create mode 100644 drivers/gpu/drm/i915/gvt/migrate.h
> 
> diff --git a/drivers/gpu/drm/i915/gvt/Makefile 
> b/drivers/gpu/drm/i915/gvt/Makefile
> index f5486cb9..a7e2e34 100644
> --- a/drivers/gpu/drm/i915/gvt/Makefile
> +++ b/drivers/gpu/drm/i915/gvt/Makefile
> @@ -1,7 +1,7 @@
>  GVT_DIR := gvt
>  GVT_SOURCE := gvt.o aperture_gm.o handlers.o vgpu.o trace_points.o 
> firmware.o \
>       interrupt.o gtt.o cfg_space.o opregion.o mmio.o display.o edid.o \
> -     execlist.o scheduler.o sched_policy.o render.o cmd_parser.o
> +     execlist.o scheduler.o sched_policy.o render.o cmd_parser.o migrate.o
>  
>  ccflags-y                            += -I$(src) -I$(src)/$(GVT_DIR)
>  i915-y                                       += $(addprefix $(GVT_DIR)/, 
> $(GVT_SOURCE))
> diff --git a/drivers/gpu/drm/i915/gvt/gvt.c b/drivers/gpu/drm/i915/gvt/gvt.c
> index c27c683..e40af70 100644
> --- a/drivers/gpu/drm/i915/gvt/gvt.c
> +++ b/drivers/gpu/drm/i915/gvt/gvt.c
> @@ -54,6 +54,7 @@ static const struct intel_gvt_ops intel_gvt_ops = {
>       .vgpu_reset = intel_gvt_reset_vgpu,
>       .vgpu_activate = intel_gvt_activate_vgpu,
>       .vgpu_deactivate = intel_gvt_deactivate_vgpu,
> +     .vgpu_save_restore = intel_gvt_save_restore,
>  };
>  
>  /**
> diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
> index 23eeb7c..12aa3b8 100644
> --- a/drivers/gpu/drm/i915/gvt/gvt.h
> +++ b/drivers/gpu/drm/i915/gvt/gvt.h
> @@ -46,6 +46,7 @@
>  #include "sched_policy.h"
>  #include "render.h"
>  #include "cmd_parser.h"
> +#include "migrate.h"
>  
>  #define GVT_MAX_VGPU 8
>  
> @@ -431,6 +432,8 @@ void intel_gvt_reset_vgpu_locked(struct intel_vgpu *vgpu, 
> bool dmlr,
>  void intel_gvt_reset_vgpu(struct intel_vgpu *vgpu);
>  void intel_gvt_activate_vgpu(struct intel_vgpu *vgpu);
>  void intel_gvt_deactivate_vgpu(struct intel_vgpu *vgpu);
> +int intel_gvt_save_restore(struct intel_vgpu *vgpu, char *buf,
> +                         size_t count, uint64_t off, bool restore);
>  
>  /* validating GM functions */
>  #define vgpu_gmadr_is_aperture(vgpu, gmadr) \
> @@ -513,6 +516,8 @@ struct intel_gvt_ops {
>       void (*vgpu_reset)(struct intel_vgpu *);
>       void (*vgpu_activate)(struct intel_vgpu *);
>       void (*vgpu_deactivate)(struct intel_vgpu *);
> +     int  (*vgpu_save_restore)(struct intel_vgpu *, char *buf,
> +                               size_t count, uint64_t off, bool restore);
>  };
>  
>  
> diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c 
> b/drivers/gpu/drm/i915/gvt/kvmgt.c
> index e9f11a9..d4ede29 100644
> --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> @@ -670,6 +670,9 @@ static ssize_t intel_vgpu_rw(struct mdev_device *mdev, 
> char *buf,
>                                               bar0_start + pos, buf, count);
>               }
>               break;
> +     case VFIO_PCI_DEVICE_STATE_REGION_INDEX:
> +             ret = intel_gvt_ops->vgpu_save_restore(vgpu, buf, count, pos, 
> is_write);
> +             break;
>       case VFIO_PCI_BAR2_REGION_INDEX:
>       case VFIO_PCI_BAR3_REGION_INDEX:
>       case VFIO_PCI_BAR4_REGION_INDEX:
> @@ -688,6 +691,10 @@ static ssize_t intel_vgpu_read(struct mdev_device *mdev, 
> char __user *buf,
>  {
>       unsigned int done = 0;
>       int ret;
> +     unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
> +
> +     if (index == VFIO_PCI_DEVICE_STATE_REGION_INDEX)
> +             return intel_vgpu_rw(mdev, (char *)buf, count, ppos, false);
>  
>       while (count) {
>               size_t filled;
> @@ -748,6 +755,10 @@ static ssize_t intel_vgpu_write(struct mdev_device *mdev,
>  {
>       unsigned int done = 0;
>       int ret;
> +     unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
> +
> +     if (index == VFIO_PCI_DEVICE_STATE_REGION_INDEX)
> +             return intel_vgpu_rw(mdev, (char *)buf, count, ppos, true);
>  
>       while (count) {
>               size_t filled;
> @@ -1037,6 +1048,14 @@ static long intel_vgpu_ioctl(struct mdev_device *mdev, 
> unsigned int cmd,
>               case VFIO_PCI_VGA_REGION_INDEX:
>                       gvt_dbg_core("get region info index:%d\n", info.index);
>                       break;
> +             case VFIO_PCI_DEVICE_STATE_REGION_INDEX:
> +                     info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
> +                     info.size = MIGRATION_IMG_MAX_SIZE;
> +
> +                     info.flags =    VFIO_REGION_INFO_FLAG_READ |
> +                                     VFIO_REGION_INFO_FLAG_WRITE;
> +                     break;
> +
>               default:
>                       {
>                               struct vfio_region_info_cap_type cap_type;
> diff --git a/drivers/gpu/drm/i915/gvt/migrate.c 
> b/drivers/gpu/drm/i915/gvt/migrate.c
> new file mode 100644
> index 0000000..72743df
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/gvt/migrate.c
> @@ -0,0 +1,715 @@
> +/*
> + * Copyright(c) 2011-2016 Intel Corporation. All rights reserved.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
> FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 
> THE
> + * SOFTWARE.
> + *
> + * Authors:
> + *
> + * Contributors:
> + *
> + */
> +
> +#include "i915_drv.h"
> +#include "gvt.h"
> +#include "i915_pvinfo.h"
> +
> +#define INV (-1)
> +#define RULES_NUM(x) (sizeof(x)/sizeof(gvt_migration_obj_t))
> +#define FOR_EACH_OBJ(obj, rules) \
> +     for (obj = rules; obj->region.type != GVT_MIGRATION_NONE; obj++)
> +#define MIG_VREG_RESTORE(vgpu, off)                                  \
> +     {                                                               \
> +             u32 data = vgpu_vreg(vgpu, (off));                      \
> +             u64 pa = intel_vgpu_mmio_offset_to_gpa(vgpu, off);      \
> +             intel_vgpu_emulate_mmio_write(vgpu, pa, &data, 4);      \
> +     }
> +
> +/* s - struct
> + * t - type of obj
> + * m - size of obj
> + * ops - operation override callback func
> + */
> +#define MIGRATION_UNIT(_s, _t, _m, _ops) {           \
> +.img         = NULL,                                 \
> +.region.type = _t,                                   \
> +.region.size = _m,                           \
> +.ops         = &(_ops),                              \
> +.name                = "["#_s":"#_t"]\0"                     \
> +}
> +
> +#define MIGRATION_END {              \
> +     NULL, NULL, 0,          \
> +     {GVT_MIGRATION_NONE, 0},\
> +     NULL,   \
> +     NULL    \
> +}
> +
> +static int image_header_load(const gvt_migration_obj_t *obj, u32 size);
> +static int image_header_save(const gvt_migration_obj_t *obj);
> +static int vreg_load(const gvt_migration_obj_t *obj, u32 size);
> +static int vreg_save(const gvt_migration_obj_t *obj);
> +static int sreg_load(const gvt_migration_obj_t *obj, u32 size);
> +static int sreg_save(const gvt_migration_obj_t *obj);
> +static int vcfg_space_load(const gvt_migration_obj_t *obj, u32 size);
> +static int vcfg_space_save(const gvt_migration_obj_t *obj);
> +static int vggtt_load(const gvt_migration_obj_t *obj, u32 size);
> +static int vggtt_save(const gvt_migration_obj_t *obj);
> +static int workload_load(const gvt_migration_obj_t *obj, u32 size);
> +static int workload_save(const gvt_migration_obj_t *obj);
> +/***********************************************
> + * Internal Static Functions
> + ***********************************************/
> +struct gvt_migration_operation_t vReg_ops = {
> +     .pre_copy = NULL,
> +     .pre_save = vreg_save,
> +     .pre_load = vreg_load,
> +     .post_load = NULL,
> +};
> +
> +struct gvt_migration_operation_t sReg_ops = {
> +     .pre_copy = NULL,
> +     .pre_save = sreg_save,
> +     .pre_load = sreg_load,
> +     .post_load = NULL,
> +};
> +
> +struct gvt_migration_operation_t vcfg_space_ops = {
> +     .pre_copy = NULL,
> +     .pre_save = vcfg_space_save,
> +     .pre_load = vcfg_space_load,
> +     .post_load = NULL,
> +};
> +
> +struct gvt_migration_operation_t vgtt_info_ops = {
> +     .pre_copy = NULL,
> +     .pre_save = vggtt_save,
> +     .pre_load = vggtt_load,
> +     .post_load = NULL,
> +};
> +
> +struct gvt_migration_operation_t image_header_ops = {
> +     .pre_copy = NULL,
> +     .pre_save = image_header_save,
> +     .pre_load = image_header_load,
> +     .post_load = NULL,
> +};
> +
> +struct gvt_migration_operation_t workload_ops = {
> +     .pre_copy = NULL,
> +     .pre_save = workload_save,
> +     .pre_load = workload_load,
> +     .post_load = NULL,
> +};
> +
> +/* gvt_device_objs[] are list of gvt_migration_obj_t objs
> + * Each obj has its operation method to save to qemu image
> + * and restore from qemu image during the migration.
> + *
> + * for each saved bject, it will have a region header
> + * struct gvt_region_t {
> + *   region_type;
> + *   region_size;
> + * }
> + *__________________  _________________   __________________
> + *|x64 (Source)    |  |image region    |  |x64 (Target)    |
> + *|________________|  |________________|  |________________|
> + *|    Region A    |  |   Region A     |  |   Region A     |
> + *|    Header      |  |   offset=0     |  | allocate a page|
> + *|    content     |  |                |  | copy data here |
> + *|----------------|  |     ...        |  |----------------|
> + *|    Region B    |  |     ...        |  |   Region B     |
> + *|    Header      |  |----------------|  |                |
> + *|    content        |   Region B     |  |                |
> + *|----------------|  |   offset=4096  |  |----------------|
> + *                    |                |
> + *                    |----------------|
> + *
> + * On the target side, it will parser the incomming data copy
> + * from Qemu image, and apply difference restore handlers depends
> + * on the region type.
> + */
> +static struct gvt_migration_obj_t gvt_device_objs[] = {
> +     MIGRATION_UNIT(struct intel_vgpu,
> +                     GVT_MIGRATION_HEAD,
> +                     sizeof(gvt_image_header_t),
> +                     image_header_ops),
> +     MIGRATION_UNIT(struct intel_vgpu,
> +                     GVT_MIGRATION_CFG_SPACE,
> +                     INTEL_GVT_MAX_CFG_SPACE_SZ,
> +                     vcfg_space_ops),
> +     MIGRATION_UNIT(struct intel_vgpu,
> +                     GVT_MIGRATION_SREG,
> +                     GVT_MMIO_SIZE, sReg_ops),
> +     MIGRATION_UNIT(struct intel_vgpu,
> +                     GVT_MIGRATION_VREG,
> +                     GVT_MMIO_SIZE, vReg_ops),
> +     MIGRATION_UNIT(struct intel_vgpu,
> +                     GVT_MIGRATION_GTT,
> +                     0, vgtt_info_ops),
> +     MIGRATION_UNIT(struct intel_vgpu,
> +                     GVT_MIGRATION_WORKLOAD,
> +                     0, workload_ops),
> +     MIGRATION_END,
> +};
> +
> +static inline void
> +update_image_region_start_pos(gvt_migration_obj_t *obj, int pos)
> +{
> +     obj->offset = pos;
> +}
> +
> +static inline void
> +update_image_region_base(gvt_migration_obj_t *obj, void *base)
> +{
> +     obj->img = base;
> +}
> +
> +static inline void
> +update_status_region_base(gvt_migration_obj_t *obj, void *base)
> +{
> +     obj->vgpu = base;
> +}
> +
> +static inline gvt_migration_obj_t *
> +find_migration_obj(enum gvt_migration_type_t type)
> +{
> +     gvt_migration_obj_t *obj;
> +     for ( obj = gvt_device_objs; obj->region.type != GVT_MIGRATION_NONE; 
> obj++)
> +             if (obj->region.type == type)
> +                     return obj;
> +     return NULL;
> +}
> +
> +static int image_header_save(const gvt_migration_obj_t *obj)
> +{
> +     gvt_region_t region;
> +     gvt_image_header_t header;
> +
> +     region.type = GVT_MIGRATION_HEAD;
> +     region.size = sizeof(gvt_image_header_t);
> +     memcpy(obj->img, &region, sizeof(gvt_region_t));
> +
> +     header.version = GVT_MIGRATION_VERSION;
> +     header.data_size = obj->offset;
> +     header.crc_check = 0; /* CRC check skipped for now*/
> +
> +     memcpy(obj->img + sizeof(gvt_region_t), &header, 
> sizeof(gvt_image_header_t));
> +
> +     return sizeof(gvt_region_t) + sizeof(gvt_image_header_t);
> +}
> +
> +static int image_header_load(const gvt_migration_obj_t *obj, u32 size)
> +{
> +     gvt_image_header_t header;
> +
> +     if (unlikely(size != sizeof(gvt_image_header_t))) {
> +             gvt_err("migration object size is not match between target \
> +                             and image!!! memsize=%d imgsize=%d\n",
> +             obj->region.size,
> +             size);
> +             return INV;
> +     }
> +
> +     memcpy(&header, obj->img + obj->offset, sizeof(gvt_image_header_t));
> +
> +     return header.data_size;
> +}
> +
> +static int vcfg_space_save(const gvt_migration_obj_t *obj)
> +{
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     int n_transfer = INV;
> +     void *src = vgpu->cfg_space.virtual_cfg_space;
> +     void *des = obj->img + obj->offset;
> +
> +     memcpy(des, &obj->region, sizeof(gvt_region_t));
> +
> +     des += sizeof(gvt_region_t);
> +     n_transfer = obj->region.size;
> +
> +     memcpy(des, src, n_transfer);
> +     return sizeof(gvt_region_t) + n_transfer;
> +}
> +
> +static int vcfg_space_load(const gvt_migration_obj_t *obj, u32 size)
> +{
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     void *dest = vgpu->cfg_space.virtual_cfg_space;
> +     int n_transfer = INV;
> +
> +     if (unlikely(size != obj->region.size)) {
> +             gvt_err("migration object size is not match between target \
> +                             and image!!! memsize=%d imgsize=%d\n",
> +             obj->region.size,
> +             size);
> +             return n_transfer;
> +     } else {
> +             n_transfer = obj->region.size;
> +             memcpy(dest, obj->img + obj->offset, n_transfer);
> +     }
> +
> +     return n_transfer;
> +}
> +
> +static int sreg_save(const gvt_migration_obj_t *obj)
> +{
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     int n_transfer = INV;
> +     void *src = vgpu->mmio.sreg;
> +     void *des = obj->img + obj->offset;
> +
> +     memcpy(des, &obj->region, sizeof(gvt_region_t));
> +
> +     des += sizeof(gvt_region_t);
> +     n_transfer = obj->region.size;
> +
> +     memcpy(des, src, n_transfer);
> +     return sizeof(gvt_region_t) + n_transfer;
> +}
> +
> +static int sreg_load(const gvt_migration_obj_t *obj, u32 size)
> +{
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     void *dest = vgpu->mmio.sreg;
> +     int n_transfer = INV;
> +
> +     if (unlikely(size != obj->region.size)) {
> +             gvt_err("migration object size is not match between target \
> +                             and image!!! memsize=%d imgsize=%d\n",
> +             obj->region.size,
> +             size);
> +             return n_transfer;
> +     } else {
> +             n_transfer = obj->region.size;
> +             memcpy(dest, obj->img + obj->offset, n_transfer);
> +     }
> +
> +     return n_transfer;
> +}
> +
> +static int vreg_save(const gvt_migration_obj_t *obj)
> +{
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     int n_transfer = INV;
> +     void *src = vgpu->mmio.vreg;
> +     void *des = obj->img + obj->offset;
> +
> +     memcpy(des, &obj->region, sizeof(gvt_region_t));
> +
> +     des += sizeof(gvt_region_t);
> +     n_transfer = obj->region.size;
> +
> +     memcpy(des, src, n_transfer);
> +     return sizeof(gvt_region_t) + n_transfer;
> +}
> +
> +static int vreg_load(const gvt_migration_obj_t *obj, u32 size)
> +{
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     void *dest = vgpu->mmio.vreg;
> +     int n_transfer = INV;
> +
> +     if (unlikely(size != obj->region.size)) {
> +             gvt_err("migration object size is not match between target \
> +                             and image!!! memsize=%d imgsize=%d\n",
> +             obj->region.size,
> +             size);
> +             return n_transfer;
> +     } else {
> +             n_transfer = obj->region.size;
> +             memcpy(dest, obj->img + obj->offset, n_transfer);
> +     }
> +     return n_transfer;
> +}
> +
> +static int workload_save(const gvt_migration_obj_t *obj)
> +{
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
> +     int n_transfer = INV;
> +     struct gvt_region_t region;
> +     struct intel_engine_cs *engine;
> +     struct intel_vgpu_workload *pos, *n;
> +     unsigned int i;
> +     struct gvt_pending_workload_t workload;
> +     void *des = obj->img + obj->offset;
> +     unsigned int num = 0;
> +     u32 sz = sizeof(gvt_pending_workload_t);
> +
> +     for_each_engine(engine, dev_priv, i) {
> +             list_for_each_entry_safe(pos, n,
> +                     &vgpu->workload_q_head[engine->id], list) {
> +                     workload.ring_id = pos->ring_id;
> +                     memcpy(&workload.elsp_dwords, &pos->elsp_dwords,
> +                             sizeof(struct intel_vgpu_elsp_dwords));
> +                     memcpy(des + sizeof(gvt_region_t) + (num * sz), 
> &workload, sz);
> +                     num++;
> +             }
> +     }
> +
> +     region.type = GVT_MIGRATION_WORKLOAD;
> +     region.size = num * sz;
> +     memcpy(des, &obj->region, sizeof(gvt_region_t));
> +
> +     n_transfer = obj->region.size;
> +
> +     return sizeof(gvt_region_t) + n_transfer;
> +}
> +
> +static int workload_load(const gvt_migration_obj_t *obj, u32 size)
> +{
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
> +     int n_transfer = INV;
> +     struct gvt_pending_workload_t workload;
> +     struct intel_engine_cs *engine;
> +     void *src = obj->img + obj->offset;
> +     u64 pa, off;
> +     u32 sz = sizeof(gvt_pending_workload_t);
> +     int i, j;
> +
> +     if (size == 0)
> +             return size;
> +
> +     if (unlikely(size % sz) != 0) {
> +             gvt_err("migration object size is not match between target \
> +                             and image!!! memsize=%d imgsize=%d\n",
> +             obj->region.size,
> +             size);
> +             return n_transfer;
> +     }
> +
> +     for (i = 0; i < size / sz; i++) {
> +             memcpy(&workload, src + (i * sz), sz);
> +             engine = dev_priv->engine[workload.ring_id];
> +             off = i915_mmio_reg_offset(RING_ELSP(engine));
> +             pa = intel_vgpu_mmio_offset_to_gpa(vgpu, off);
> +             for (j = 0; j < 4; j++) {
> +                     intel_vgpu_emulate_mmio_write(vgpu, pa,
> +                                     &workload.elsp_dwords.data[j], 4);
> +             }
> +     }
> +
> +     n_transfer = size;
> +
> +     return n_transfer;
> +}
> +
> +static int
> +mig_ggtt_save_restore(struct intel_vgpu_mm *ggtt_mm,
> +             void *data, u64 gm_offset,
> +             u64 gm_sz,
> +             bool save_to_image)
> +{
> +     struct intel_vgpu *vgpu = ggtt_mm->vgpu;
> +     struct intel_gvt_gtt_gma_ops *gma_ops = vgpu->gvt->gtt.gma_ops;
> +
> +     void *ptable;
> +     int sz;
> +     int shift = vgpu->gvt->device_info.gtt_entry_size_shift;
> +
> +     ptable = ggtt_mm->virtual_page_table +
> +         (gma_ops->gma_to_ggtt_pte_index(gm_offset) << shift);
> +     sz = (gm_sz >> GTT_PAGE_SHIFT) << shift;
> +
> +     if (save_to_image)
> +             memcpy(data, ptable, sz);
> +     else
> +             memcpy(ptable, data, sz);
> +
> +     return sz;
> +}
> +
> +static int vggtt_save(const gvt_migration_obj_t *obj)
> +{
> +     int ret = INV;
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     struct intel_vgpu_mm *ggtt_mm = vgpu->gtt.ggtt_mm;
> +     void *des = obj->img + obj->offset;
> +     struct gvt_region_t region;
> +     int sz;
> +
> +     u64 aperture_offset = vgpu_guest_aperture_offset(vgpu);
> +     u64 aperture_sz = vgpu_aperture_sz(vgpu);
> +     u64 hidden_gm_offset = vgpu_guest_hidden_offset(vgpu);
> +     u64 hidden_gm_sz = vgpu_hidden_sz(vgpu);
> +
> +     des += sizeof(gvt_region_t);
> +
> +     /*TODO:512MB GTT takes total 1024KB page table size, optimization here*/
> +
> +     gvt_dbg_core("Guest aperture=0x%llx (HW: 0x%llx) Guest Hidden=0x%llx 
> (HW:0x%llx)\n",
> +             aperture_offset, vgpu_aperture_offset(vgpu),
> +             hidden_gm_offset, vgpu_hidden_offset(vgpu));
> +
> +     /*TODO:to be fixed after removal of address ballooning */
> +     ret = 0;
> +
> +     /* aperture */
> +     sz = mig_ggtt_save_restore(ggtt_mm, des,
> +             aperture_offset, aperture_sz, true);
> +     des += sz;
> +     ret += sz;
> +
> +     /* hidden gm */
> +     sz = mig_ggtt_save_restore(ggtt_mm, des,
> +             hidden_gm_offset, hidden_gm_sz, true);
> +     des += sz;
> +     ret += sz;
> +
> +     /* Save the total size of this session */
> +     region.type = GVT_MIGRATION_GTT;
> +     region.size = ret;
> +     memcpy(obj->img + obj->offset, &region, sizeof(gvt_region_t));
> +
> +     ret += sizeof(gvt_region_t);
> +
> +     return ret;
> +}
> +
> +static int vggtt_load(const gvt_migration_obj_t *obj, u32 size)
> +{
> +     int ret;
> +     int ggtt_index;
> +     void *src;
> +     int sz;
> +
> +     struct intel_vgpu *vgpu = (struct intel_vgpu *) obj->vgpu;
> +     struct intel_vgpu_mm *ggtt_mm = vgpu->gtt.ggtt_mm;
> +
> +     int shift = vgpu->gvt->device_info.gtt_entry_size_shift;
> +
> +     /* offset to bar1 beginning */
> +     u64 dest_aperture_offset = vgpu_guest_aperture_offset(vgpu);
> +     u64 aperture_sz = vgpu_aperture_sz(vgpu);
> +     u64 dest_hidden_gm_offset = vgpu_guest_hidden_offset(vgpu);
> +     u64 hidden_gm_sz = vgpu_hidden_sz(vgpu);
> +
> +     gvt_dbg_core("Guest aperture=0x%llx (HW: 0x%llx) Guest Hidden=0x%llx 
> (HW:0x%llx)\n",
> +             dest_aperture_offset, vgpu_aperture_offset(vgpu),
> +             dest_hidden_gm_offset, vgpu_hidden_offset(vgpu));
> +
> +     if ((size>>shift) !=
> +                     ((aperture_sz + hidden_gm_sz) >> GTT_PAGE_SHIFT)) {
> +             gvt_err("ggtt restore failed due to page table size not 
> match\n");
> +             return INV;
> +     }
> +
> +     ret = 0;
> +     src = obj->img + obj->offset;
> +
> +     /* aperture */
> +     sz = mig_ggtt_save_restore(ggtt_mm,\
> +             src, dest_aperture_offset, aperture_sz, false);
> +     src += sz;
> +     ret += sz;
> +
> +     /* hidden GM */
> +     sz = mig_ggtt_save_restore(ggtt_mm, src,
> +                     dest_hidden_gm_offset, hidden_gm_sz, false);
> +     ret += sz;
> +
> +     /* aperture/hidden GTT emulation from Source to Target */
> +     for (ggtt_index = 0; ggtt_index < ggtt_mm->page_table_entry_cnt;
> +                     ggtt_index++) {
> +
> +             if (vgpu_gmadr_is_valid(vgpu, ggtt_index<<GTT_PAGE_SHIFT)) {
> +                     struct intel_gvt_gtt_pte_ops *ops = 
> vgpu->gvt->gtt.pte_ops;
> +                     struct intel_gvt_gtt_entry e;
> +                     u64 offset;
> +                     u64 pa;
> +
> +                     /* TODO: hardcode to 64bit right now */
> +                     offset = vgpu->gvt->device_info.gtt_start_offset
> +                             + (ggtt_index<<shift);
> +
> +                     pa = intel_vgpu_mmio_offset_to_gpa(vgpu, offset);
> +
> +                     /* read out virtual GTT entity and
> +                      * trigger emulate write
> +                      */
> +                     ggtt_get_guest_entry(ggtt_mm, &e, ggtt_index);
> +                     if (ops->test_present(&e)) {
> +                     /* same as gtt_emulate
> +                      * _write(vgt, offset, &e.val64, 1<<shift);
> +                      * Using vgt_emulate_write as to align with vReg load
> +                      */
> +                             intel_vgpu_emulate_mmio_write(vgpu, pa, 
> &e.val64, 1<<shift);
> +                     }
> +             }
> +     }
> +
> +     return ret;
> +}
> +
> +static int vgpu_save(const void *img)
> +{
> +     gvt_migration_obj_t *node;
> +     int n_img_actual_saved = 0;
> +
> +     /* go by obj rules one by one */
> +     FOR_EACH_OBJ(node, gvt_device_objs) {
> +             int n_img = INV;
> +
> +             /* obj will copy data to image file img.offset */
> +             update_image_region_start_pos(node, n_img_actual_saved);
> +             if (node->ops->pre_save == NULL) {
> +                     n_img = 0;
> +             } else {
> +                     n_img = node->ops->pre_save(node);
> +                     if (n_img == INV) {
> +                             gvt_err("Save obj %s failed\n",
> +                                             node->name);
> +                             n_img_actual_saved = INV;
> +                             break;
> +                     }
> +             }
> +             /* show GREEN on screen with colorred term */
> +             gvt_dbg_core("Save obj %s success with %d bytes\n",
> +                            node->name, n_img);
> +             n_img_actual_saved += n_img;
> +
> +             if (n_img_actual_saved >= MIGRATION_IMG_MAX_SIZE) {
> +                     gvt_err("Image size overflow!!! data=%d MAX=%ld\n",
> +                             n_img_actual_saved,
> +                             MIGRATION_IMG_MAX_SIZE);
> +                     /* Mark as invalid */
> +                     n_img_actual_saved = INV;
> +                     break;
> +             }
> +     }
> +     /* update the header with real image size */
> +     node = find_migration_obj(GVT_MIGRATION_HEAD);
> +     update_image_region_start_pos(node, n_img_actual_saved);
> +     node->ops->pre_save(node);
> +     return n_img_actual_saved;
> +}
> +
> +static int vgpu_restore(void *img)
> +{
> +     gvt_migration_obj_t *node;
> +     gvt_region_t region;
> +     int n_img_actual_recv = 0;
> +     u32 n_img_actual_size;
> +
> +     /* load image header at first to get real size */
> +     memcpy(&region, img, sizeof(gvt_region_t));
> +     if (region.type != GVT_MIGRATION_HEAD) {
> +             gvt_err("Invalid image. Doesn't start with image_head\n");
> +             return INV;
> +     }
> +
> +     n_img_actual_recv += sizeof(gvt_region_t);
> +     node = find_migration_obj(region.type);
> +     update_image_region_start_pos(node, n_img_actual_recv);
> +     n_img_actual_size = node->ops->pre_load(node, region.size);
> +     if (n_img_actual_size == INV) {
> +             gvt_err("Load img %s failed\n", node->name);
> +             return INV;
> +     }
> +
> +     if (n_img_actual_size >= MIGRATION_IMG_MAX_SIZE) {
> +             gvt_err("Invalid image. magic_id offset = 0x%x\n",
> +                             n_img_actual_size);
> +             return INV;
> +     }
> +
> +     n_img_actual_recv += sizeof(gvt_image_header_t);
> +
> +     do {
> +             int n_img = INV;
> +             /* parse each region head to get type and size */
> +             memcpy(&region, img + n_img_actual_recv, sizeof(gvt_region_t));
> +             node = find_migration_obj(region.type);
> +             if (node == NULL)
> +                     break;
> +             n_img_actual_recv += sizeof(gvt_region_t);
> +             update_image_region_start_pos(node, n_img_actual_recv);
> +
> +             if (node->ops->pre_load == NULL) {
> +                     n_img = 0;
> +             } else {
> +                     n_img = node->ops->pre_load(node, region.size);
> +                     if (n_img == INV) {
> +                             /* Error occurred. colored as RED */
> +                             gvt_err("Load obj %s failed\n",
> +                                             node->name);
> +                             n_img_actual_recv = INV;
> +                             break;
> +                     }
> +             }
> +             /* show GREEN on screen with colorred term */
> +             gvt_dbg_core("Load obj %s success with %d bytes.\n",
> +                            node->name, n_img);
> +             n_img_actual_recv += n_img;
> +     } while (n_img_actual_recv < MIGRATION_IMG_MAX_SIZE);
> +
> +     return n_img_actual_recv;
> +}
> +
> +int intel_gvt_save_restore(struct intel_vgpu *vgpu, char *buf,
> +                         size_t count, uint64_t off, bool restore)
> +{
> +     void *img_base;
> +     gvt_migration_obj_t *node;
> +     int ret = 0;
> +
> +     if (off != 0) {
> +             gvt_vgpu_err("Migration should start from the \
> +                          begining of the image\n");
> +             return -EFAULT;
> +     }
> +
> +     img_base = vzalloc(MIGRATION_IMG_MAX_SIZE);
> +     if (img_base == NULL) {
> +             gvt_vgpu_err("Unable to allocate size: %ld\n",
> +                             MIGRATION_IMG_MAX_SIZE);
> +             return -EFAULT;
> +     }
> +
> +     FOR_EACH_OBJ(node, gvt_device_objs) {
> +             update_image_region_base(node, img_base);
> +             update_image_region_start_pos(node, INV);
> +             update_status_region_base(node, vgpu);
> +     }
> +
> +     if (restore) {
> +             if (copy_from_user(img_base + off, buf, count)) {
> +                     ret = -EFAULT;
> +                     goto exit;
> +             }
> +             vgpu->pv_notified = true;
> +             if (vgpu_restore(img_base) == INV) {
> +                     ret = -EFAULT;
> +                     goto exit;
> +             }
> +     } else {
> +             vgpu_save(img_base);
> +             if (copy_to_user(buf, img_base + off, count)) {
> +                     ret = -EFAULT;
> +                     goto exit;
> +             }
> +     }
> +
> +exit:
> +     vfree(img_base);
> +
> +     return ret;
> +}
> diff --git a/drivers/gpu/drm/i915/gvt/migrate.h 
> b/drivers/gpu/drm/i915/gvt/migrate.h
> new file mode 100644
> index 0000000..5a81be4
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/gvt/migrate.h
> @@ -0,0 +1,82 @@
> +/*
> + * Copyright(c) 2011-2016 Intel Corporation. All rights reserved.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
> FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 
> THE
> + * SOFTWARE.
> + */
> +
> +#ifndef __GVT_MIGRATE_H__
> +#define __GVT_MIGRATE_H__
> +
> +/* Assume 9MB is eough to descript VM kernel state */
> +#define MIGRATION_IMG_MAX_SIZE (9*1024UL*1024UL)
> +#define GVT_MMIO_SIZE (2*1024UL*1024UL)
> +#define GVT_MIGRATION_VERSION        0
> +
> +enum gvt_migration_type_t {
> +     GVT_MIGRATION_NONE,
> +     GVT_MIGRATION_HEAD,
> +     GVT_MIGRATION_CFG_SPACE,
> +     GVT_MIGRATION_VREG,
> +     GVT_MIGRATION_SREG,
> +     GVT_MIGRATION_GTT,
> +     GVT_MIGRATION_WORKLOAD,
> +};
> +
> +typedef struct gvt_pending_workload_t{
> +     int ring_id;
> +     struct intel_vgpu_elsp_dwords elsp_dwords;
> +} gvt_pending_workload_t;
> +
> +typedef struct gvt_region_t {
> +     enum gvt_migration_type_t type;
> +     u32 size;               /* obj size of bytes to read/write */
> +} gvt_region_t;
> +
> +typedef struct gvt_migration_obj_t {
> +     void *img;
> +     void *vgpu;
> +     u32 offset;
> +     gvt_region_t region;
> +     /* operation func defines how data save-restore */
> +     struct gvt_migration_operation_t *ops;
> +     char *name;
> +} gvt_migration_obj_t;
> +
> +typedef struct gvt_migration_operation_t {
> +     /* called during pre-copy stage, VM is still alive */
> +     int (*pre_copy)(const gvt_migration_obj_t *obj);
> +     /* called before when VM was paused,
> +      * return bytes transferred
> +      */
> +     int (*pre_save)(const gvt_migration_obj_t *obj);
> +     /* called before load the state of device */
> +     int (*pre_load)(const gvt_migration_obj_t *obj, u32 size);
> +     /* called after load the state of device, VM already alive */
> +     int (*post_load)(const gvt_migration_obj_t *obj, u32 size);
> +} gvt_migration_operation_t;
> +
> +typedef struct gvt_image_header_t {
> +     int version;
> +     int data_size;
> +     u64 crc_check;
> +     u64 global_data[64];
> +} gvt_image_header_t;
> +
> +#endif
> diff --git a/drivers/gpu/drm/i915/gvt/mmio.c b/drivers/gpu/drm/i915/gvt/mmio.c
> index 980ec89..0467e28 100644
> --- a/drivers/gpu/drm/i915/gvt/mmio.c
> +++ b/drivers/gpu/drm/i915/gvt/mmio.c
> @@ -50,6 +50,20 @@ int intel_vgpu_gpa_to_mmio_offset(struct intel_vgpu *vgpu, 
> u64 gpa)
>       return gpa - gttmmio_gpa;
>  }
>  
> +/**
> + * intel_vgpu_mmio_offset_to_GPA - translate a MMIO offset to GPA
> + * @vgpu: a vGPU
> + *
> + * Returns:
> + * Zero on success, negative error code if failed
> + */
> +int intel_vgpu_mmio_offset_to_gpa(struct intel_vgpu *vgpu, u64 offset)
> +{
> +     return offset + ((*(u64 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_0)) &
> +                     ~GENMASK(3, 0));
> +}
> +
> +
>  #define reg_is_mmio(gvt, reg)  \
>       (reg >= 0 && reg < gvt->device_info.mmio_size)
>  
> diff --git a/drivers/gpu/drm/i915/gvt/mmio.h b/drivers/gpu/drm/i915/gvt/mmio.h
> index 32cd64d..4198159 100644
> --- a/drivers/gpu/drm/i915/gvt/mmio.h
> +++ b/drivers/gpu/drm/i915/gvt/mmio.h
> @@ -82,6 +82,7 @@ void intel_vgpu_reset_mmio(struct intel_vgpu *vgpu, bool 
> dmlr);
>  void intel_vgpu_clean_mmio(struct intel_vgpu *vgpu);
>  
>  int intel_vgpu_gpa_to_mmio_offset(struct intel_vgpu *vgpu, u64 gpa);
> +int intel_vgpu_mmio_offset_to_gpa(struct intel_vgpu *vgpu, u64 offset);
>  
>  int intel_vgpu_emulate_mmio_read(struct intel_vgpu *vgpu, u64 pa,
>                               void *p_data, unsigned int bytes);
> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> index 544cf93..ac19c05 100644
> --- a/include/uapi/linux/vfio.h
> +++ b/include/uapi/linux/vfio.h
> @@ -436,7 +436,8 @@ enum {
>        * between described ranges are unimplemented.
>        */
>       VFIO_PCI_VGA_REGION_INDEX,
> -     VFIO_PCI_NUM_REGIONS = 9 /* Fixed user ABI, region indexes >=9 use */
> +     VFIO_PCI_DEVICE_STATE_REGION_INDEX,
> +     VFIO_PCI_NUM_REGIONS = 10 /* Fixed user ABI, region indexes >=10 use */
>                                /* device specific cap to define content. */
>  };
>  
> -- 
> 2.7.4
> 
> 
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK