On Thu, Oct 30, 2025 at 09:31:29PM +0100, Michał Winiarski wrote:
> Connect the helpers to allow save and restore of VRAM migration data in
> stop_copy / resume device state.
>
> Co-developed-by: Lukasz Laguna <[email protected]>
> Signed-off-by: Lukasz Laguna <[email protected]>
> Signed-off-by: Michał Winiarski <[email protected]>
> ---
> drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c | 15 ++
> drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c | 213 ++++++++++++++++++
> drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h | 5 +
> .../drm/xe/xe_gt_sriov_pf_migration_types.h | 2 +
> drivers/gpu/drm/xe/xe_sriov_pf_control.c | 3 +
> 5 files changed, 238 insertions(+)
>
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> b/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> index 7cd7cae950bc7..de0f63610e780 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> @@ -880,6 +880,18 @@ static int pf_handle_vf_save_data(struct xe_gt *gt,
> unsigned int vfid)
> return -EAGAIN;
> }
>
> + if (xe_gt_sriov_pf_migration_save_test(gt, vfid,
> XE_SRIOV_MIGRATION_DATA_TYPE_VRAM)) {
> + ret = xe_gt_sriov_pf_migration_vram_save(gt, vfid);
> + if (ret == -EAGAIN)
> + return -EAGAIN;
> + else if (ret)
> + return ret;
> +
> + xe_gt_sriov_pf_migration_save_clear(gt, vfid,
> XE_SRIOV_MIGRATION_DATA_TYPE_VRAM);
> +
> + return -EAGAIN;
> + }
> +
> return 0;
> }
>
> @@ -1095,6 +1107,9 @@ static int pf_handle_vf_restore_data(struct xe_gt *gt,
> unsigned int vfid)
> case XE_SRIOV_MIGRATION_DATA_TYPE_GUC:
> ret = xe_gt_sriov_pf_migration_guc_restore(gt, vfid, data);
> break;
> + case XE_SRIOV_MIGRATION_DATA_TYPE_VRAM:
> + ret = xe_gt_sriov_pf_migration_vram_restore(gt, vfid, data);
> + break;
> default:
> xe_gt_sriov_notice(gt, "Skipping VF%u unknown data type: %d\n",
> vfid, data->type);
> break;
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> index 5e90aeafeeb41..7ccd43545fdac 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> @@ -19,6 +19,7 @@
> #include "xe_gt_sriov_printk.h"
> #include "xe_guc_buf.h"
> #include "xe_guc_ct.h"
> +#include "xe_migrate.h"
> #include "xe_mmio.h"
> #include "xe_sriov.h"
> #include "xe_sriov_migration_data.h"
> @@ -505,6 +506,207 @@ int xe_gt_sriov_pf_migration_mmio_restore(struct xe_gt
> *gt, unsigned int vfid,
> return pf_restore_vf_mmio_mig_data(gt, vfid, data);
> }
>
> +static ssize_t pf_migration_vram_size(struct xe_gt *gt, unsigned int vfid)
> +{
> + if (!xe_gt_is_main_type(gt))
> + return 0;
> +
> + return xe_gt_sriov_pf_config_get_lmem(gt, vfid);
> +}
> +
> +static struct dma_fence *__pf_save_restore_vram(struct xe_gt *gt, unsigned
> int vfid,
> + struct xe_bo *vram, u64
> vram_offset,
> + struct xe_bo *sysmem, u64
> sysmem_offset,
> + size_t size, bool save)
> +{
> + struct dma_fence *ret = NULL;
> + struct drm_exec exec;
> + int err;
> +
> + drm_exec_init(&exec, DRM_EXEC_INTERRUPTIBLE_WAIT, 0);
It is a bit incongruent that the dma-resv lock is interruptible here.
> + drm_exec_until_all_locked(&exec) {
> + err = drm_exec_lock_obj(&exec, &vram->ttm.base);
> + drm_exec_retry_on_contention(&exec);
> + if (err) {
> + ret = ERR_PTR(err);
> + goto err;
> + }
> +
> + err = drm_exec_lock_obj(&exec, &sysmem->ttm.base);
> + drm_exec_retry_on_contention(&exec);
> + if (err) {
> + ret = ERR_PTR(err);
> + goto err;
> + }
> + }
> +
> + ret = xe_migrate_vram_copy_chunk(vram, vram_offset, sysmem,
> sysmem_offset, size,
> + save ? XE_MIGRATE_COPY_TO_SRAM :
> XE_MIGRATE_COPY_TO_VRAM);
> +
> +err:
> + drm_exec_fini(&exec);
> +
> + return ret;
> +}
> +
> +#define PF_VRAM_SAVE_RESTORE_TIMEOUT (5 * HZ)
> +static int pf_save_vram_chunk(struct xe_gt *gt, unsigned int vfid,
> + struct xe_bo *src_vram, u64 src_vram_offset,
> + size_t size)
> +{
> + struct xe_sriov_migration_data *data;
> + struct dma_fence *fence;
> + int ret;
> +
> + data = xe_sriov_migration_data_alloc(gt_to_xe(gt));
> + if (!data)
> + return -ENOMEM;
> +
> + ret = xe_sriov_migration_data_init(data, gt->tile->id, gt->info.id,
> + XE_SRIOV_MIGRATION_DATA_TYPE_VRAM,
> + src_vram_offset, size);
> + if (ret)
> + goto fail;
> +
> + fence = __pf_save_restore_vram(gt, vfid,
> + src_vram, src_vram_offset,
> + data->bo, 0, size, true);
> +
> + ret = dma_fence_wait_timeout(fence, false,
> PF_VRAM_SAVE_RESTORE_TIMEOUT);
Then here the dma-fence wait is non-interruptible.
> + dma_fence_put(fence);
> + if (!ret) {
> + ret = -ETIME;
> + goto fail;
> + }
> +
> + xe_gt_sriov_dbg_verbose(gt, "VF%u VRAM data save (%zu bytes)\n", vfid,
> size);
> + pf_dump_mig_data(gt, vfid, data);
> +
> + ret = xe_gt_sriov_pf_migration_save_produce(gt, vfid, data);
> + if (ret)
> + goto fail;
> +
> + return 0;
> +
> +fail:
> + xe_sriov_migration_data_free(data);
> + return ret;
> +}
> +
> +#define VF_VRAM_STATE_CHUNK_MAX_SIZE SZ_512M
> +static int pf_save_vf_vram_mig_data(struct xe_gt *gt, unsigned int vfid)
> +{
> + struct xe_gt_sriov_migration_data *migration = pf_pick_gt_migration(gt,
> vfid);
> + loff_t *offset = &migration->save.vram_offset;
> + struct xe_bo *vram;
> + size_t vram_size, chunk_size;
> + int ret;
> +
> + vram = xe_gt_sriov_pf_config_get_lmem_obj(gt, vfid);
> + if (!vram)
> + return -ENXIO;
> +
> + vram_size = xe_bo_size(vram);
> +
> + xe_gt_assert(gt, *offset < vram_size);
> +
> + chunk_size = min(vram_size - *offset, VF_VRAM_STATE_CHUNK_MAX_SIZE);
> +
> + ret = pf_save_vram_chunk(gt, vfid, vram, *offset, chunk_size);
> + if (ret)
> + goto fail;
> +
> + *offset += chunk_size;
> +
> + xe_bo_put(vram);
> +
> + if (*offset < vram_size)
> + return -EAGAIN;
> +
> + return 0;
> +
> +fail:
> + xe_bo_put(vram);
> + xe_gt_sriov_err(gt, "Failed to save VF%u VRAM data (%pe)\n", vfid,
> ERR_PTR(ret));
> + return ret;
> +}
> +
> +static int pf_restore_vf_vram_mig_data(struct xe_gt *gt, unsigned int vfid,
> + struct xe_sriov_migration_data *data)
> +{
> + u64 end = data->hdr.offset + data->hdr.size;
> + struct dma_fence *fence;
> + struct xe_bo *vram;
> + size_t size;
> + int ret = 0;
> +
> + vram = xe_gt_sriov_pf_config_get_lmem_obj(gt, vfid);
> + if (!vram)
> + return -ENXIO;
> +
> + size = xe_bo_size(vram);
> +
> + if (end > size || end < data->hdr.size) {
> + ret = -EINVAL;
> + goto err;
> + }
> +
> + xe_gt_sriov_dbg_verbose(gt, "VF%u VRAM data restore (%llu bytes)\n",
> vfid, data->size);
> + pf_dump_mig_data(gt, vfid, data);
> +
> + fence = __pf_save_restore_vram(gt, vfid, vram, data->hdr.offset,
> + data->bo, 0, data->hdr.size, false);
> + ret = dma_fence_wait_timeout(fence, false,
> PF_VRAM_SAVE_RESTORE_TIMEOUT);
And also here the dma-fence wait is non-interruptible.
Aside from the incongruence, the usage of drm-exec, dma-fences looks correct.
Matt
> + dma_fence_put(fence);
> + if (!ret) {
> + ret = -ETIME;
> + goto err;
> + }
> +
> + return 0;
> +err:
> + xe_bo_put(vram);
> + xe_gt_sriov_err(gt, "Failed to restore VF%u VRAM data (%pe)\n", vfid,
> ERR_PTR(ret));
> + return ret;
> +}
> +
> +/**
> + * xe_gt_sriov_pf_migration_vram_save() - Save VF VRAM migration data.
> + * @gt: the &xe_gt
> + * @vfid: the VF identifier (can't be 0)
> + *
> + * This function is for PF only.
> + *
> + * Return: 0 on success or a negative error code on failure.
> + */
> +int xe_gt_sriov_pf_migration_vram_save(struct xe_gt *gt, unsigned int vfid)
> +{
> + xe_gt_assert(gt, IS_SRIOV_PF(gt_to_xe(gt)));
> + xe_gt_assert(gt, vfid != PFID);
> + xe_gt_assert(gt, vfid <= xe_sriov_pf_get_totalvfs(gt_to_xe(gt)));
> +
> + return pf_save_vf_vram_mig_data(gt, vfid);
> +}
> +
> +/**
> + * xe_gt_sriov_pf_migration_vram_restore() - Restore VF VRAM migration data.
> + * @gt: the &xe_gt
> + * @vfid: the VF identifier (can't be 0)
> + *
> + * This function is for PF only.
> + *
> + * Return: 0 on success or a negative error code on failure.
> + */
> +int xe_gt_sriov_pf_migration_vram_restore(struct xe_gt *gt, unsigned int
> vfid,
> + struct xe_sriov_migration_data *data)
> +{
> + xe_gt_assert(gt, IS_SRIOV_PF(gt_to_xe(gt)));
> + xe_gt_assert(gt, vfid != PFID);
> + xe_gt_assert(gt, vfid <= xe_sriov_pf_get_totalvfs(gt_to_xe(gt)));
> +
> + return pf_restore_vf_vram_mig_data(gt, vfid, data);
> +}
> +
> /**
> * xe_gt_sriov_pf_migration_size() - Total size of migration data from all
> components within a GT.
> * @gt: the &xe_gt
> @@ -544,6 +746,13 @@ ssize_t xe_gt_sriov_pf_migration_size(struct xe_gt *gt,
> unsigned int vfid)
> size += sizeof(struct xe_sriov_pf_migration_hdr);
> total += size;
>
> + size = pf_migration_vram_size(gt, vfid);
> + if (size < 0)
> + return size;
> + if (size > 0)
> + size += sizeof(struct xe_sriov_pf_migration_hdr);
> + total += size;
> +
> return total;
> }
>
> @@ -602,6 +811,7 @@ void xe_gt_sriov_pf_migration_save_init(struct xe_gt *gt,
> unsigned int vfid)
> struct xe_gt_sriov_migration_data *migration = pf_pick_gt_migration(gt,
> vfid);
>
> migration->save.data_remaining = 0;
> + migration->save.vram_offset = 0;
>
> xe_gt_assert(gt, pf_migration_guc_size(gt, vfid) > 0);
> set_bit(XE_SRIOV_MIGRATION_DATA_TYPE_GUC,
> &migration->save.data_remaining);
> @@ -611,6 +821,9 @@ void xe_gt_sriov_pf_migration_save_init(struct xe_gt *gt,
> unsigned int vfid)
>
> xe_gt_assert(gt, pf_migration_mmio_size(gt, vfid) > 0);
> set_bit(XE_SRIOV_MIGRATION_DATA_TYPE_MMIO,
> &migration->save.data_remaining);
> +
> + if (pf_migration_vram_size(gt, vfid) > 0)
> + set_bit(XE_SRIOV_MIGRATION_DATA_TYPE_VRAM,
> &migration->save.data_remaining);
> }
>
> /**
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h
> b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h
> index b0eec94fea3a6..85b43b2cceb73 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h
> @@ -25,6 +25,11 @@ int xe_gt_sriov_pf_migration_ggtt_restore(struct xe_gt
> *gt, unsigned int vfid,
> int xe_gt_sriov_pf_migration_mmio_save(struct xe_gt *gt, unsigned int vfid);
> int xe_gt_sriov_pf_migration_mmio_restore(struct xe_gt *gt, unsigned int
> vfid,
> struct xe_sriov_migration_data *data);
> +int xe_gt_sriov_pf_migration_vram_save(struct xe_gt *gt, unsigned int vfid);
> +int xe_gt_sriov_pf_migration_vram_restore(struct xe_gt *gt, unsigned int
> vfid,
> + struct xe_sriov_migration_data *data);
> +
> +void xe_gt_sriov_pf_migration_save_init(struct xe_gt *gt, unsigned int vfid);
>
> ssize_t xe_gt_sriov_pf_migration_size(struct xe_gt *gt, unsigned int vfid);
>
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration_types.h
> b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration_types.h
> index 9f24878690d9c..f50c64241e9c0 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration_types.h
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration_types.h
> @@ -20,6 +20,8 @@ struct xe_gt_sriov_migration_data {
> struct {
> /** @save.data_remaining: bitmap of migration types that need
> to be saved */
> unsigned long data_remaining;
> + /** @save.vram_offset: last saved offset within VRAM, used for
> chunked VRAM save */
> + loff_t vram_offset;
> } save;
> };
>
> diff --git a/drivers/gpu/drm/xe/xe_sriov_pf_control.c
> b/drivers/gpu/drm/xe/xe_sriov_pf_control.c
> index c2768848daba1..aac8ecb861545 100644
> --- a/drivers/gpu/drm/xe/xe_sriov_pf_control.c
> +++ b/drivers/gpu/drm/xe/xe_sriov_pf_control.c
> @@ -5,6 +5,7 @@
>
> #include "xe_device.h"
> #include "xe_gt_sriov_pf_control.h"
> +#include "xe_gt_sriov_pf_migration.h"
> #include "xe_sriov_migration_data.h"
> #include "xe_sriov_pf_control.h"
> #include "xe_sriov_printk.h"
> @@ -171,6 +172,8 @@ int xe_sriov_pf_control_trigger_save_vf(struct xe_device
> *xe, unsigned int vfid)
> return ret;
>
> for_each_gt(gt, xe, id) {
> + xe_gt_sriov_pf_migration_save_init(gt, vfid);
> +
> ret = xe_gt_sriov_pf_control_trigger_save_vf(gt, vfid);
> if (ret)
> return ret;
> --
> 2.50.1
>
