[PATCH V4 mlx5-next 10/13] vfio/mlx5: Expose migration commands over mlx5 device

Yishai Hadas
2021-10-26T09:08:21Z

Expose migration commands over the device, it includes: suspend, resume,
get vhca id, query/save/load state.

As part of this adds the APIs and data structure that are needed to
manage the migration data.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
drivers/vfio/pci/mlx5/cmd.c | 356 ++++++++++++++++++++++++++++++++++++
drivers/vfio/pci/mlx5/cmd.h | 43 +++++
2 files changed, 399 insertions(+)
create mode 100644 drivers/vfio/pci/mlx5/cmd.c
create mode 100644 drivers/vfio/pci/mlx5/cmd.h

diff --git a/drivers/vfio/pci/mlx5/cmd.c b/drivers/vfio/pci/mlx5/cmd.c
new file mode 100644
index 000000000000..add791398d08
--- /dev/null
+++ b/drivers/vfio/pci/mlx5/cmd.c
@@ -0,0 +1,356 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/*
+ * Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved
+ */
+
+#include "cmd.h"
+
+int mlx5vf_cmd_suspend_vhca(struct pci_dev *pdev, u16 vhca_id, u16 op_mod)
+{
+ struct mlx5_core_dev *mdev = mlx5_vf_get_core_dev(pdev);
+ u32 out[MLX5_ST_SZ_DW(suspend_vhca_out)] = {};
+ u32 in[MLX5_ST_SZ_DW(suspend_vhca_in)] = {};
+ int ret;
+
+ if (!mdev)
+ return -ENOTCONN;
+
+ MLX5_SET(suspend_vhca_in, in, opcode, MLX5_CMD_OP_SUSPEND_VHCA);
+ MLX5_SET(suspend_vhca_in, in, vhca_id, vhca_id);
+ MLX5_SET(suspend_vhca_in, in, op_mod, op_mod);
+
+ ret = mlx5_cmd_exec_inout(mdev, suspend_vhca, in, out);
+ mlx5_vf_put_core_dev(mdev);
+ return ret;
+}
+
+int mlx5vf_cmd_resume_vhca(struct pci_dev *pdev, u16 vhca_id, u16 op_mod)
+{
+ struct mlx5_core_dev *mdev = mlx5_vf_get_core_dev(pdev);
+ u32 out[MLX5_ST_SZ_DW(resume_vhca_out)] = {};
+ u32 in[MLX5_ST_SZ_DW(resume_vhca_in)] = {};
+ int ret;
+
+ if (!mdev)
+ return -ENOTCONN;
+
+ MLX5_SET(resume_vhca_in, in, opcode, MLX5_CMD_OP_RESUME_VHCA);
+ MLX5_SET(resume_vhca_in, in, vhca_id, vhca_id);
+ MLX5_SET(resume_vhca_in, in, op_mod, op_mod);
+
+ ret = mlx5_cmd_exec_inout(mdev, resume_vhca, in, out);
+ mlx5_vf_put_core_dev(mdev);
+ return ret;
+}
+
+int mlx5vf_cmd_query_vhca_migration_state(struct pci_dev *pdev, u16 vhca_id,
+ u32 *state_size)
+{
+ struct mlx5_core_dev *mdev = mlx5_vf_get_core_dev(pdev);
+ u32 out[MLX5_ST_SZ_DW(query_vhca_migration_state_out)] = {};
+ u32 in[MLX5_ST_SZ_DW(query_vhca_migration_state_in)] = {};
+ int ret;
+
+ if (!mdev)
+ return -ENOTCONN;
+
+ MLX5_SET(query_vhca_migration_state_in, in, opcode,
+ MLX5_CMD_OP_QUERY_VHCA_MIGRATION_STATE);
+ MLX5_SET(query_vhca_migration_state_in, in, vhca_id, vhca_id);
+ MLX5_SET(query_vhca_migration_state_in, in, op_mod, 0);
+
+ ret = mlx5_cmd_exec_inout(mdev, query_vhca_migration_state, in, out);
+ if (ret)
+ goto end;
+
+ *state_size = MLX5_GET(query_vhca_migration_state_out, out,
+ required_umem_size);
+
+end:
+ mlx5_vf_put_core_dev(mdev);
+ return ret;
+}
+
+int mlx5vf_cmd_get_vhca_id(struct pci_dev *pdev, u16 function_id, u16 *vhca_id)
+{
+ struct mlx5_core_dev *mdev = mlx5_vf_get_core_dev(pdev);
+ u32 in[MLX5_ST_SZ_DW(query_hca_cap_in)] = {};
+ int out_size;
+ void *out;
+ int ret;
+
+ if (!mdev)
+ return -ENOTCONN;
+
+ out_size = MLX5_ST_SZ_BYTES(query_hca_cap_out);
+ out = kzalloc(out_size, GFP_KERNEL);
+ if (!out) {
+ ret = -ENOMEM;
+ goto end;
+ }
+
+ MLX5_SET(query_hca_cap_in, in, opcode, MLX5_CMD_OP_QUERY_HCA_CAP);
+ MLX5_SET(query_hca_cap_in, in, other_function, 1);
+ MLX5_SET(query_hca_cap_in, in, function_id, function_id);
+ MLX5_SET(query_hca_cap_in, in, op_mod,
+ MLX5_SET_HCA_CAP_OP_MOD_GENERAL_DEVICE << 1 |
+ HCA_CAP_OPMOD_GET_CUR);
+
+ ret = mlx5_cmd_exec_inout(mdev, query_hca_cap, in, out);
+ if (ret)
+ goto err_exec;
+
+ *vhca_id = MLX5_GET(query_hca_cap_out, out,
+ capability.cmd_hca_cap.vhca_id);
+
+err_exec:
+ kfree(out);
+end:
+ mlx5_vf_put_core_dev(mdev);
+ return ret;
+}
+
+static int _create_state_mkey(struct mlx5_core_dev *mdev, u32 pdn,
+ struct mlx5_vhca_state_data *state, u32 *mkey)
+{
+ struct sg_dma_page_iter dma_iter;
+ int err = 0, inlen;
+ __be64 *mtt;
+ void *mkc;
+ u32 *in;
+
+ inlen = MLX5_ST_SZ_BYTES(create_mkey_in) +
+ sizeof(*mtt) * round_up(state->num_pages, 2);
+
+ in = kvzalloc(inlen, GFP_KERNEL);
+ if (!in)
+ return -ENOMEM;
+
+ MLX5_SET(create_mkey_in, in, translations_octword_actual_size,
+ DIV_ROUND_UP(state->num_pages, 2));
+ mtt = (__be64 *)MLX5_ADDR_OF(create_mkey_in, in, klm_pas_mtt);
+
+ for_each_sgtable_dma_page(&state->mig_data.table.sgt, &dma_iter, 0)
+ *mtt++ = cpu_to_be64(sg_page_iter_dma_address(&dma_iter));
+
+ mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
+ MLX5_SET(mkc, mkc, access_mode_1_0, MLX5_MKC_ACCESS_MODE_MTT);
+ MLX5_SET(mkc, mkc, lr, 1);
+ MLX5_SET(mkc, mkc, lw, 1);
+ MLX5_SET(mkc, mkc, rr, 1);
+ MLX5_SET(mkc, mkc, rw, 1);
+ MLX5_SET(mkc, mkc, pd, pdn);
+ MLX5_SET(mkc, mkc, bsf_octword_size, 0);
+ MLX5_SET(mkc, mkc, qpn, 0xffffff);
+ MLX5_SET(mkc, mkc, log_page_size, PAGE_SHIFT);
+ MLX5_SET(mkc, mkc, translations_octword_size,
+ DIV_ROUND_UP(state->num_pages, 2));
+ MLX5_SET64(mkc, mkc, len, state->num_pages * PAGE_SIZE);
+ err = mlx5_core_create_mkey(mdev, mkey, in, inlen);
+
+ kvfree(in);
+
+ return err;
+}
+
+struct page *mlx5vf_get_migration_page(struct migration_data *data,
+ unsigned long offset)
+{
+ unsigned long cur_offset = 0;
+ struct scatterlist *sg;
+ unsigned int i;
+
+ if (offset < data->last_offset || !data->last_offset_sg) {
+ data->last_offset = 0;
+ data->last_offset_sg = data->table.sgt.sgl;
+ data->sg_last_entry = 0;
+ }
+
+ cur_offset = data->last_offset;
+
+ for_each_sg(data->last_offset_sg, sg,
+ data->table.sgt.orig_nents - data->sg_last_entry, i) {
+ if (offset < sg->length + cur_offset) {
+ data->last_offset_sg = sg;
+ data->sg_last_entry += i;
+ data->last_offset = cur_offset;
+ return nth_page(sg_page(sg),
+ (offset - cur_offset) / PAGE_SIZE);
+ }
+ cur_offset += sg->length;
+ }
+ return NULL;
+}
+
+void mlx5vf_reset_vhca_state(struct mlx5_vhca_state_data *state)
+{
+ struct migration_data *data = &state->mig_data;
+ struct sg_page_iter sg_iter;
+
+ if (!data->table.prv)
+ goto end;
+
+ /* Undo alloc_pages_bulk_array() */
+ for_each_sgtable_page(&data->table.sgt, &sg_iter, 0)
+ __free_page(sg_page_iter_page(&sg_iter));
+ sg_free_append_table(&data->table);
+end:
+ memset(state, 0, sizeof(*state));
+}
+
+int mlx5vf_add_migration_pages(struct mlx5_vhca_state_data *state,
+ unsigned int npages)
+{
+ unsigned int to_alloc = npages;
+ struct page **page_list;
+ unsigned long filled;
+ unsigned int to_fill;
+ int ret = 0;
+
+ to_fill = min_t(unsigned int, npages, PAGE_SIZE / sizeof(*page_list));
+ page_list = kvzalloc(to_fill * sizeof(*page_list), GFP_KERNEL);
+ if (!page_list)
+ return -ENOMEM;
+
+ do {
+ filled = alloc_pages_bulk_array(GFP_KERNEL, to_fill,
+ page_list);
+ if (!filled) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ to_alloc -= filled;
+ ret = sg_alloc_append_table_from_pages(
+ &state->mig_data.table, page_list, filled, 0,
+ filled << PAGE_SHIFT, UINT_MAX, SG_MAX_SINGLE_ALLOC,
+ GFP_KERNEL);
+
+ if (ret)
+ goto err;
+ /* clean input for another bulk allocation */
+ memset(page_list, 0, filled * sizeof(*page_list));
+ to_fill = min_t(unsigned int, to_alloc,
+ PAGE_SIZE / sizeof(*page_list));
+ } while (to_alloc > 0);
+
+ kvfree(page_list);
+ state->num_pages += npages;
+
+ return 0;
+
+err:
+ kvfree(page_list);
+ return ret;
+}
+
+int mlx5vf_cmd_save_vhca_state(struct pci_dev *pdev, u16 vhca_id,
+ u64 state_size,
+ struct mlx5_vhca_state_data *state)
+{
+ struct mlx5_core_dev *mdev = mlx5_vf_get_core_dev(pdev);
+ u32 out[MLX5_ST_SZ_DW(save_vhca_state_out)] = {};
+ u32 in[MLX5_ST_SZ_DW(save_vhca_state_in)] = {};
+ u32 pdn, mkey;
+ int err;
+
+ if (!mdev)
+ return -ENOTCONN;
+
+ err = mlx5_core_alloc_pd(mdev, &pdn);
+ if (err)
+ goto end;
+
+ err = mlx5vf_add_migration_pages(state,
+ DIV_ROUND_UP_ULL(state_size, PAGE_SIZE));
+ if (err < 0)
+ goto err_alloc_pages;
+
+ err = dma_map_sgtable(mdev->device, &state->mig_data.table.sgt,
+ DMA_FROM_DEVICE, 0);
+ if (err)
+ goto err_reg_dma;
+
+ err = _create_state_mkey(mdev, pdn, state, &mkey);
+ if (err)
+ goto err_create_mkey;
+
+ MLX5_SET(save_vhca_state_in, in, opcode,
+ MLX5_CMD_OP_SAVE_VHCA_STATE);
+ MLX5_SET(save_vhca_state_in, in, op_mod, 0);
+ MLX5_SET(save_vhca_state_in, in, vhca_id, vhca_id);
+ MLX5_SET(save_vhca_state_in, in, mkey, mkey);
+ MLX5_SET(save_vhca_state_in, in, size, state_size);
+
+ err = mlx5_cmd_exec_inout(mdev, save_vhca_state, in, out);
+ if (err)
+ goto err_exec;
+
+ state->state_size = MLX5_GET(save_vhca_state_out, out,
+ actual_image_size);
+
+ mlx5_core_destroy_mkey(mdev, mkey);
+ mlx5_core_dealloc_pd(mdev, pdn);
+ dma_unmap_sgtable(mdev->device, &state->mig_data.table.sgt,
+ DMA_FROM_DEVICE, 0);
+ mlx5_vf_put_core_dev(mdev);
+
+ return 0;
+
+err_exec:
+ mlx5_core_destroy_mkey(mdev, mkey);
+err_create_mkey:
+ dma_unmap_sgtable(mdev->device, &state->mig_data.table.sgt,
+ DMA_FROM_DEVICE, 0);
+err_reg_dma:
+ mlx5vf_reset_vhca_state(state);
+err_alloc_pages:
+ mlx5_core_dealloc_pd(mdev, pdn);
+end:
+ mlx5_vf_put_core_dev(mdev);
+ return err;
+}
+
+int mlx5vf_cmd_load_vhca_state(struct pci_dev *pdev, u16 vhca_id,
+ struct mlx5_vhca_state_data *state)
+{
+ struct mlx5_core_dev *mdev = mlx5_vf_get_core_dev(pdev);
+ u32 out[MLX5_ST_SZ_DW(save_vhca_state_out)] = {};
+ u32 in[MLX5_ST_SZ_DW(save_vhca_state_in)] = {};
+ u32 pdn, mkey;
+ int err;
+
+ if (!mdev)
+ return -ENOTCONN;
+
+ err = mlx5_core_alloc_pd(mdev, &pdn);
+ if (err)
+ goto end;
+
+ err = dma_map_sgtable(mdev->device, &state->mig_data.table.sgt,
+ DMA_TO_DEVICE, 0);
+ if (err)
+ goto err_reg;
+
+ err = _create_state_mkey(mdev, pdn, state, &mkey);
+ if (err)
+ goto err_mkey;
+
+ MLX5_SET(load_vhca_state_in, in, opcode,
+ MLX5_CMD_OP_LOAD_VHCA_STATE);
+ MLX5_SET(load_vhca_state_in, in, op_mod, 0);
+ MLX5_SET(load_vhca_state_in, in, vhca_id, vhca_id);
+ MLX5_SET(load_vhca_state_in, in, mkey, mkey);
+ MLX5_SET(load_vhca_state_in, in, size, state->state_size);
+
+ err = mlx5_cmd_exec_inout(mdev, load_vhca_state, in, out);
+
+ mlx5_core_destroy_mkey(mdev, mkey);
+err_mkey:
+ dma_unmap_sgtable(mdev->device, &state->mig_data.table.sgt,
+ DMA_TO_DEVICE, 0);
+err_reg:
+ mlx5_core_dealloc_pd(mdev, pdn);
+end:
+ mlx5_vf_put_core_dev(mdev);
+ return err;
+}
diff --git a/drivers/vfio/pci/mlx5/cmd.h b/drivers/vfio/pci/mlx5/cmd.h
new file mode 100644
index 000000000000..66221df24b19
--- /dev/null
+++ b/drivers/vfio/pci/mlx5/cmd.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/*
+ * Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ */
+
+#ifndef MLX5_VFIO_CMD_H
+#define MLX5_VFIO_CMD_H
+
+#include <linux/kernel.h>
+#include <linux/mlx5/driver.h>
+
+struct migration_data {
+ struct sg_append_table table;
+
+ struct scatterlist *last_offset_sg;
+ unsigned int sg_last_entry;
+ unsigned long last_offset;
+};
+
+/* state data of vhca to be used as part of migration flow */
+struct mlx5_vhca_state_data {
+ u64 state_size;
+ u64 num_pages;
+ u32 win_start_offset;
+ struct migration_data mig_data;
+};
+
+int mlx5vf_cmd_suspend_vhca(struct pci_dev *pdev, u16 vhca_id, u16 op_mod);
+int mlx5vf_cmd_resume_vhca(struct pci_dev *pdev, u16 vhca_id, u16 op_mod);
+int mlx5vf_cmd_query_vhca_migration_state(struct pci_dev *pdev, u16 vhca_id,
+ uint32_t *state_size);
+int mlx5vf_cmd_get_vhca_id(struct pci_dev *pdev, u16 function_id, u16 *vhca_id);
+int mlx5vf_cmd_save_vhca_state(struct pci_dev *pdev, u16 vhca_id,
+ u64 state_size,
+ struct mlx5_vhca_state_data *state);
+void mlx5vf_reset_vhca_state(struct mlx5_vhca_state_data *state);
+int mlx5vf_cmd_load_vhca_state(struct pci_dev *pdev, u16 vhca_id,
+ struct mlx5_vhca_state_data *state);
+int mlx5vf_add_migration_pages(struct mlx5_vhca_state_data *state,
+ unsigned int npages);
+struct page *mlx5vf_get_migration_page(struct migration_data *data,
+ unsigned long offset);
+#endif /* MLX5_VFIO_CMD_H */
--
2.18.1