IB/mlx5: Introduce VAR object and its alloc/destroy methods

Introduce VAR object and its alloc/destroy KABI methods. The internal
implementation uses the IB core API to manage mmap/munamp calls.

Link: https://lore.kernel.org/r/20191212110928.334995-5-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index e6aa836f1b55d811759a31e343a789ddd41dea6e..433ed48425adcc7a98b316c133d49d30f677745c 100644 (file)
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -2078,6 +2078,7 @@ static void mlx5_ib_mmap_free(struct rdma_user_mmap_entry *entry)
 {
        struct mlx5_user_mmap_entry *mentry = to_mmmap(entry);
        struct mlx5_ib_dev *dev = to_mdev(entry->ucontext->device);
+       struct mlx5_var_table *var_table = &dev->var_table;
        struct mlx5_ib_dm *mdm;
 
        switch (mentry->mmap_flag) {
@@ -2087,6 +2088,12 @@ static void mlx5_ib_mmap_free(struct rdma_user_mmap_entry *entry)
                                       mdm->size);
                kfree(mdm);
                break;
+       case MLX5_IB_MMAP_TYPE_VAR:
+               mutex_lock(&var_table->bitmap_lock);
+               clear_bit(mentry->page_idx, var_table->bitmap);
+               mutex_unlock(&var_table->bitmap_lock);
+               kfree(mentry);
+               break;
        default:
                WARN_ON(true);
        }
@@ -2255,6 +2262,15 @@ static int mlx5_ib_mmap_offset(struct mlx5_ib_dev *dev,
        return ret;
 }
 
+static u64 mlx5_entry_to_mmap_offset(struct mlx5_user_mmap_entry *entry)
+{
+       u16 cmd = entry->rdma_entry.start_pgoff >> 16;
+       u16 index = entry->rdma_entry.start_pgoff & 0xFFFF;
+
+       return (((index >> 8) << 16) | (cmd << MLX5_IB_MMAP_CMD_SHIFT) |
+               (index & 0xFF)) << PAGE_SHIFT;
+}
+
 static int mlx5_ib_mmap(struct ib_ucontext *ibcontext, struct vm_area_struct *vma)
 {
        struct mlx5_ib_ucontext *context = to_mucontext(ibcontext);
@@ -6034,6 +6050,145 @@ static void mlx5_ib_cleanup_multiport_master(struct mlx5_ib_dev *dev)
        mlx5_nic_vport_disable_roce(dev->mdev);
 }
 
+static int var_obj_cleanup(struct ib_uobject *uobject,
+                          enum rdma_remove_reason why,
+                          struct uverbs_attr_bundle *attrs)
+{
+       struct mlx5_user_mmap_entry *obj = uobject->object;
+
+       rdma_user_mmap_entry_remove(&obj->rdma_entry);
+       return 0;
+}
+
+static struct mlx5_user_mmap_entry *
+alloc_var_entry(struct mlx5_ib_ucontext *c)
+{
+       struct mlx5_user_mmap_entry *entry;
+       struct mlx5_var_table *var_table;
+       u32 page_idx;
+       int err;
+
+       var_table = &to_mdev(c->ibucontext.device)->var_table;
+       entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+       if (!entry)
+               return ERR_PTR(-ENOMEM);
+
+       mutex_lock(&var_table->bitmap_lock);
+       page_idx = find_first_zero_bit(var_table->bitmap,
+                                      var_table->num_var_hw_entries);
+       if (page_idx >= var_table->num_var_hw_entries) {
+               err = -ENOSPC;
+               mutex_unlock(&var_table->bitmap_lock);
+               goto end;
+       }
+
+       set_bit(page_idx, var_table->bitmap);
+       mutex_unlock(&var_table->bitmap_lock);
+
+       entry->address = var_table->hw_start_addr +
+                               (page_idx * var_table->stride_size);
+       entry->page_idx = page_idx;
+       entry->mmap_flag = MLX5_IB_MMAP_TYPE_VAR;
+
+       err = rdma_user_mmap_entry_insert_range(
+               &c->ibucontext, &entry->rdma_entry, var_table->stride_size,
+               MLX5_IB_MMAP_OFFSET_START << 16,
+               (MLX5_IB_MMAP_OFFSET_END << 16) + (1UL << 16) - 1);
+       if (err)
+               goto err_insert;
+
+       return entry;
+
+err_insert:
+       mutex_lock(&var_table->bitmap_lock);
+       clear_bit(page_idx, var_table->bitmap);
+       mutex_unlock(&var_table->bitmap_lock);
+end:
+       kfree(entry);
+       return ERR_PTR(err);
+}
+
+static int UVERBS_HANDLER(MLX5_IB_METHOD_VAR_OBJ_ALLOC)(
+       struct uverbs_attr_bundle *attrs)
+{
+       struct ib_uobject *uobj = uverbs_attr_get_uobject(
+               attrs, MLX5_IB_ATTR_VAR_OBJ_ALLOC_HANDLE);
+       struct mlx5_ib_ucontext *c;
+       struct mlx5_user_mmap_entry *entry;
+       u64 mmap_offset;
+       u32 length;
+       int err;
+
+       c = to_mucontext(ib_uverbs_get_ucontext(attrs));
+       if (IS_ERR(c))
+               return PTR_ERR(c);
+
+       entry = alloc_var_entry(c);
+       if (IS_ERR(entry))
+               return PTR_ERR(entry);
+
+       mmap_offset = mlx5_entry_to_mmap_offset(entry);
+       length = entry->rdma_entry.npages * PAGE_SIZE;
+       uobj->object = entry;
+
+       err = uverbs_copy_to(attrs, MLX5_IB_ATTR_VAR_OBJ_ALLOC_MMAP_OFFSET,
+                            &mmap_offset, sizeof(mmap_offset));
+       if (err)
+               goto err;
+
+       err = uverbs_copy_to(attrs, MLX5_IB_ATTR_VAR_OBJ_ALLOC_PAGE_ID,
+                            &entry->page_idx, sizeof(entry->page_idx));
+       if (err)
+               goto err;
+
+       err = uverbs_copy_to(attrs, MLX5_IB_ATTR_VAR_OBJ_ALLOC_MMAP_LENGTH,
+                            &length, sizeof(length));
+       if (err)
+               goto err;
+
+       return 0;
+
+err:
+       rdma_user_mmap_entry_remove(&entry->rdma_entry);
+       return err;
+}
+
+DECLARE_UVERBS_NAMED_METHOD(
+       MLX5_IB_METHOD_VAR_OBJ_ALLOC,
+       UVERBS_ATTR_IDR(MLX5_IB_ATTR_VAR_OBJ_ALLOC_HANDLE,
+                       MLX5_IB_OBJECT_VAR,
+                       UVERBS_ACCESS_NEW,
+                       UA_MANDATORY),
+       UVERBS_ATTR_PTR_OUT(MLX5_IB_ATTR_VAR_OBJ_ALLOC_PAGE_ID,
+                          UVERBS_ATTR_TYPE(u32),
+                          UA_MANDATORY),
+       UVERBS_ATTR_PTR_OUT(MLX5_IB_ATTR_VAR_OBJ_ALLOC_MMAP_LENGTH,
+                          UVERBS_ATTR_TYPE(u32),
+                          UA_MANDATORY),
+       UVERBS_ATTR_PTR_OUT(MLX5_IB_ATTR_VAR_OBJ_ALLOC_MMAP_OFFSET,
+                           UVERBS_ATTR_TYPE(u64),
+                           UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_METHOD_DESTROY(
+       MLX5_IB_METHOD_VAR_OBJ_DESTROY,
+       UVERBS_ATTR_IDR(MLX5_IB_ATTR_VAR_OBJ_DESTROY_HANDLE,
+                       MLX5_IB_OBJECT_VAR,
+                       UVERBS_ACCESS_DESTROY,
+                       UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_OBJECT(MLX5_IB_OBJECT_VAR,
+                           UVERBS_TYPE_ALLOC_IDR(var_obj_cleanup),
+                           &UVERBS_METHOD(MLX5_IB_METHOD_VAR_OBJ_ALLOC),
+                           &UVERBS_METHOD(MLX5_IB_METHOD_VAR_OBJ_DESTROY));
+
+static bool var_is_supported(struct ib_device *device)
+{
+       struct mlx5_ib_dev *dev = to_mdev(device);
+
+       return (MLX5_CAP_GEN_64(dev->mdev, general_obj_types) &
+                       MLX5_GENERAL_OBJ_TYPES_CAP_VIRTIO_NET_Q);
+}
+
 ADD_UVERBS_ATTRIBUTES_SIMPLE(
        mlx5_ib_dm,
        UVERBS_OBJECT_DM,
@@ -6064,6 +6219,8 @@ static const struct uapi_definition mlx5_ib_defs[] = {
        UAPI_DEF_CHAIN_OBJ_TREE(UVERBS_OBJECT_FLOW_ACTION,
                                &mlx5_ib_flow_action),
        UAPI_DEF_CHAIN_OBJ_TREE(UVERBS_OBJECT_DM, &mlx5_ib_dm),
+       UAPI_DEF_CHAIN_OBJ_TREE_NAMED(MLX5_IB_OBJECT_VAR,
+                               UAPI_DEF_IS_OBJ_SUPPORTED(var_is_supported)),
        {}
 };
 

diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index d3ec11fb59a6cfcd27afdcf396fdf65488128b16..676462c8909f8288f674d1fdd392f2bde9b7c07f 100644 (file)
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -71,6 +71,11 @@
 
 #define MLX5_MKEY_PAGE_SHIFT_MASK __mlx5_mask(mkc, log_page_size)
 
+enum {
+       MLX5_IB_MMAP_OFFSET_START = 9,
+       MLX5_IB_MMAP_OFFSET_END = 255,
+};
+
 enum {
        MLX5_IB_MMAP_CMD_SHIFT  = 8,
        MLX5_IB_MMAP_CMD_MASK   = 0xff,
@@ -120,6 +125,7 @@ enum {
 
 enum mlx5_ib_mmap_type {
        MLX5_IB_MMAP_TYPE_MEMIC = 1,
+       MLX5_IB_MMAP_TYPE_VAR = 2,
 };
 
 #define MLX5_LOG_SW_ICM_BLOCK_SIZE(dev)                                        \
@@ -563,6 +569,7 @@ struct mlx5_user_mmap_entry {
        struct rdma_user_mmap_entry rdma_entry;
        u8 mmap_flag;
        u64 address;
+       u32 page_idx;
 };
 
 struct mlx5_ib_dm {

diff --git a/include/uapi/rdma/mlx5_user_ioctl_cmds.h b/include/uapi/rdma/mlx5_user_ioctl_cmds.h
index 20d88307f75f3b9b24fc062eadb79aa90d8fd1dc..afe7da6f2b8e9f4cbc72567a48f1a02a016cd03e 100644 (file)
--- a/include/uapi/rdma/mlx5_user_ioctl_cmds.h
+++ b/include/uapi/rdma/mlx5_user_ioctl_cmds.h
@@ -115,6 +115,22 @@ enum mlx5_ib_devx_obj_methods {
        MLX5_IB_METHOD_DEVX_OBJ_ASYNC_QUERY,
 };
 
+enum mlx5_ib_var_alloc_attrs {
+       MLX5_IB_ATTR_VAR_OBJ_ALLOC_HANDLE = (1U << UVERBS_ID_NS_SHIFT),
+       MLX5_IB_ATTR_VAR_OBJ_ALLOC_MMAP_OFFSET,
+       MLX5_IB_ATTR_VAR_OBJ_ALLOC_MMAP_LENGTH,
+       MLX5_IB_ATTR_VAR_OBJ_ALLOC_PAGE_ID,
+};
+
+enum mlx5_ib_var_obj_destroy_attrs {
+       MLX5_IB_ATTR_VAR_OBJ_DESTROY_HANDLE = (1U << UVERBS_ID_NS_SHIFT),
+};
+
+enum mlx5_ib_var_obj_methods {
+       MLX5_IB_METHOD_VAR_OBJ_ALLOC = (1U << UVERBS_ID_NS_SHIFT),
+       MLX5_IB_METHOD_VAR_OBJ_DESTROY,
+};
+
 enum mlx5_ib_devx_umem_reg_attrs {
        MLX5_IB_ATTR_DEVX_UMEM_REG_HANDLE = (1U << UVERBS_ID_NS_SHIFT),
        MLX5_IB_ATTR_DEVX_UMEM_REG_ADDR,
@@ -156,6 +172,7 @@ enum mlx5_ib_objects {
        MLX5_IB_OBJECT_FLOW_MATCHER,
        MLX5_IB_OBJECT_DEVX_ASYNC_CMD_FD,
        MLX5_IB_OBJECT_DEVX_ASYNC_EVENT_FD,
+       MLX5_IB_OBJECT_VAR,
 };
 
 enum mlx5_ib_flow_matcher_create_attrs {