From 6829c1c2b371674a05562a39d608b5cf48351bea Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Mon, 12 Nov 2018 22:59:52 +0200 Subject: [PATCH] RDMA/uverbs: Add helpers to mark uapi functions as unsupported We have many cases where parts of the uapi are not supported in a driver, needs a certain protocol, or whatever. It is best to reflect this directly into the struct uverbs_api when it is built so that everything is simply blocked off, and future introspection can report a proper supported list. This is done by adding some additional helpers to the definition list language that disable objects based on a 'supported' call back, and a helper that disables based on a NULL struct ib_device function pointer. Disablement is global. For instance, if a driver disables an object then everything connected to that object is removed, including core methods. Signed-off-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky --- drivers/infiniband/core/rdma_core.h | 6 +- drivers/infiniband/core/uverbs_main.c | 2 +- drivers/infiniband/core/uverbs_uapi.c | 175 +++++++++++++++++++++++++++++++--- include/rdma/uverbs_ioctl.h | 31 ++++++ 4 files changed, 196 insertions(+), 18 deletions(-) diff --git a/drivers/infiniband/core/rdma_core.h b/drivers/infiniband/core/rdma_core.h index e39e9da1..ce042e51 100644 --- a/drivers/infiniband/core/rdma_core.h +++ b/drivers/infiniband/core/rdma_core.h @@ -121,6 +121,7 @@ void release_ufile_idr_uobject(struct ib_uverbs_file *ufile); struct uverbs_api_object { const struct uverbs_obj_type *type_attrs; const struct uverbs_obj_type_class *type_class; + u8 disabled:1; }; struct uverbs_api_ioctl_method { @@ -130,6 +131,7 @@ struct uverbs_api_ioctl_method { u16 bundle_size; u8 use_stack:1; u8 driver_method:1; + u8 disabled:1; u8 key_bitmap_len; u8 destroy_bkey; }; @@ -138,7 +140,6 @@ struct uverbs_api_attr { struct uverbs_attr_spec spec; }; -struct uverbs_api_object; struct uverbs_api { /* radix tree contains struct uverbs_api_* pointers */ struct radix_tree_root radix; @@ -152,8 +153,7 @@ uapi_get_object(struct uverbs_api *uapi, u16 object_id) } char *uapi_key_format(char *S, unsigned int key); -struct uverbs_api *uverbs_alloc_api(const struct uapi_definition *driver_def, - enum rdma_driver_id driver_id); +struct uverbs_api *uverbs_alloc_api(struct ib_device *ibdev); void uverbs_disassociate_api_pre(struct ib_uverbs_device *uverbs_dev); void uverbs_disassociate_api(struct uverbs_api *uapi); void uverbs_destroy_api(struct uverbs_api *uapi); diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c index 9a3b88d..375121a4d 100644 --- a/drivers/infiniband/core/uverbs_main.c +++ b/drivers/infiniband/core/uverbs_main.c @@ -1224,7 +1224,7 @@ static int ib_uverbs_create_uapi(struct ib_device *device, { struct uverbs_api *uapi; - uapi = uverbs_alloc_api(device->driver_def, device->driver_id); + uapi = uverbs_alloc_api(device); if (IS_ERR(uapi)) return PTR_ERR(uapi); diff --git a/drivers/infiniband/core/uverbs_uapi.c b/drivers/infiniband/core/uverbs_uapi.c index cb35f18..9a904dd 100644 --- a/drivers/infiniband/core/uverbs_uapi.c +++ b/drivers/infiniband/core/uverbs_uapi.c @@ -167,11 +167,33 @@ static int uapi_merge_obj_tree(struct uverbs_api *uapi, return 0; } -static int uapi_merge_def(struct uverbs_api *uapi, +static int uapi_disable_elm(struct uverbs_api *uapi, + const struct uapi_definition *def, + u32 obj_key) +{ + bool exists; + + if (def->scope == UAPI_SCOPE_OBJECT) { + struct uverbs_api_object *obj_elm; + + obj_elm = uapi_add_get_elm( + uapi, obj_key, sizeof(*obj_elm), &exists); + if (IS_ERR(obj_elm)) + return PTR_ERR(obj_elm); + obj_elm->disabled = 1; + return 0; + } + + WARN_ON(true); + return -EINVAL; +} + +static int uapi_merge_def(struct uverbs_api *uapi, struct ib_device *ibdev, const struct uapi_definition *def_list, bool is_driver) { const struct uapi_definition *def = def_list; + u32 cur_obj_key = UVERBS_API_KEY_ERR; int rc; if (!def_list) @@ -180,7 +202,7 @@ static int uapi_merge_def(struct uverbs_api *uapi, for (;; def++) { switch ((enum uapi_definition_kind)def->kind) { case UAPI_DEF_CHAIN: - rc = uapi_merge_def(uapi, def->chain, is_driver); + rc = uapi_merge_def(uapi, ibdev, def->chain, is_driver); if (rc) return rc; continue; @@ -190,6 +212,7 @@ static int uapi_merge_def(struct uverbs_api *uapi, def->chain_obj_tree->id)) return -EINVAL; + cur_obj_key = uapi_key_obj(def->object_start.object_id); rc = uapi_merge_obj_tree(uapi, def->chain_obj_tree, is_driver); if (rc) @@ -198,6 +221,25 @@ static int uapi_merge_def(struct uverbs_api *uapi, case UAPI_DEF_END: return 0; + + case UAPI_DEF_IS_SUPPORTED_DEV_FN: { + void **ibdev_fn = (void *)ibdev + def->needs_fn_offset; + + if (*ibdev_fn) + continue; + rc = uapi_disable_elm(uapi, def, cur_obj_key); + if (rc) + return rc; + continue; + } + + case UAPI_DEF_IS_SUPPORTED_FUNC: + if (def->func_is_supported(ibdev)) + continue; + rc = uapi_disable_elm(uapi, def, cur_obj_key); + if (rc) + return rc; + continue; } WARN_ON(true); return -EINVAL; @@ -286,18 +328,122 @@ static int uapi_finalize(struct uverbs_api *uapi) return 0; } -void uverbs_destroy_api(struct uverbs_api *uapi) +static void uapi_remove_range(struct uverbs_api *uapi, u32 start, u32 last) { struct radix_tree_iter iter; void __rcu **slot; - if (!uapi) - return; - - radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) { + radix_tree_for_each_slot (slot, &uapi->radix, &iter, start) { + if (iter.index > last) + return; kfree(rcu_dereference_protected(*slot, true)); radix_tree_iter_delete(&uapi->radix, &iter, slot); } +} + +static void uapi_remove_object(struct uverbs_api *uapi, u32 obj_key) +{ + uapi_remove_range(uapi, obj_key, + obj_key | UVERBS_API_METHOD_KEY_MASK | + UVERBS_API_ATTR_KEY_MASK); +} + +static void uapi_remove_method(struct uverbs_api *uapi, u32 method_key) +{ + uapi_remove_range(uapi, method_key, + method_key | UVERBS_API_ATTR_KEY_MASK); +} + + +static u32 uapi_get_obj_id(struct uverbs_attr_spec *spec) +{ + if (spec->type == UVERBS_ATTR_TYPE_IDR || + spec->type == UVERBS_ATTR_TYPE_FD) + return spec->u.obj.obj_type; + if (spec->type == UVERBS_ATTR_TYPE_IDRS_ARRAY) + return spec->u2.objs_arr.obj_type; + return UVERBS_API_KEY_ERR; +} + +static void uapi_finalize_disable(struct uverbs_api *uapi) +{ + struct radix_tree_iter iter; + u32 starting_key = 0; + bool scan_again = false; + void __rcu **slot; + +again: + radix_tree_for_each_slot (slot, &uapi->radix, &iter, starting_key) { + if (uapi_key_is_object(iter.index)) { + struct uverbs_api_object *obj_elm = + rcu_dereference_protected(*slot, true); + + if (obj_elm->disabled) { + /* Have to check all the attrs again */ + scan_again = true; + starting_key = iter.index; + uapi_remove_object(uapi, iter.index); + goto again; + } + continue; + } + + if (uapi_key_is_ioctl_method(iter.index)) { + struct uverbs_api_ioctl_method *method_elm = + rcu_dereference_protected(*slot, true); + + if (method_elm->disabled) { + starting_key = iter.index; + uapi_remove_method(uapi, iter.index); + goto again; + } + continue; + } + + if (uapi_key_is_attr(iter.index)) { + struct uverbs_api_attr *attr_elm = + rcu_dereference_protected(*slot, true); + const struct uverbs_api_object *tmp_obj; + u32 obj_key; + + /* + * If the method has a mandatory object handle + * attribute which relies on an object which is not + * present then the entire method is uncallable. + */ + if (!attr_elm->spec.mandatory) + continue; + obj_key = uapi_get_obj_id(&attr_elm->spec); + if (obj_key == UVERBS_API_KEY_ERR) + continue; + tmp_obj = uapi_get_object(uapi, obj_key); + if (tmp_obj && !tmp_obj->disabled) + continue; + + starting_key = iter.index; + uapi_remove_method( + uapi, + iter.index & (UVERBS_API_OBJ_KEY_MASK | + UVERBS_API_METHOD_KEY_MASK)); + goto again; + } + + WARN_ON(false); + } + + if (!scan_again) + return; + scan_again = false; + starting_key = 0; + goto again; +} + +void uverbs_destroy_api(struct uverbs_api *uapi) +{ + if (!uapi) + return; + + uapi_remove_range(uapi, 0, U32_MAX); kfree(uapi); } @@ -306,8 +452,7 @@ static const struct uapi_definition uverbs_core_api[] = { {}, }; -struct uverbs_api *uverbs_alloc_api(const struct uapi_definition *driver_def, - enum rdma_driver_id driver_id) +struct uverbs_api *uverbs_alloc_api(struct ib_device *ibdev) { struct uverbs_api *uapi; int rc; @@ -317,15 +462,16 @@ struct uverbs_api *uverbs_alloc_api(const struct uapi_definition *driver_def, return ERR_PTR(-ENOMEM); INIT_RADIX_TREE(&uapi->radix, GFP_KERNEL); - uapi->driver_id = driver_id; + uapi->driver_id = ibdev->driver_id; - rc = uapi_merge_def(uapi, uverbs_core_api, false); + rc = uapi_merge_def(uapi, ibdev, uverbs_core_api, false); if (rc) goto err; - rc = uapi_merge_def(uapi, driver_def, true); + rc = uapi_merge_def(uapi, ibdev, ibdev->driver_def, true); if (rc) goto err; + uapi_finalize_disable(uapi); rc = uapi_finalize(uapi); if (rc) goto err; @@ -333,8 +479,9 @@ struct uverbs_api *uverbs_alloc_api(const struct uapi_definition *driver_def, return uapi; err: if (rc != -ENOMEM) - pr_err("Setup of uverbs_api failed, kernel parsing tree description is not valid (%d)??\n", - rc); + dev_err(&ibdev->dev, + "Setup of uverbs_api failed, kernel parsing tree description is not valid (%d)??\n", + rc); uverbs_destroy_api(uapi); return ERR_PTR(rc); diff --git a/include/rdma/uverbs_ioctl.h b/include/rdma/uverbs_ioctl.h index 9fa0cca..130f05e 100644 --- a/include/rdma/uverbs_ioctl.h +++ b/include/rdma/uverbs_ioctl.h @@ -300,10 +300,17 @@ enum uapi_definition_kind { UAPI_DEF_END = 0, UAPI_DEF_CHAIN_OBJ_TREE, UAPI_DEF_CHAIN, + UAPI_DEF_IS_SUPPORTED_FUNC, + UAPI_DEF_IS_SUPPORTED_DEV_FN, +}; + +enum uapi_definition_scope { + UAPI_SCOPE_OBJECT = 1, }; struct uapi_definition { u8 kind; + u8 scope; union { struct { u16 object_id; @@ -311,11 +318,35 @@ struct uapi_definition { }; union { + bool (*func_is_supported)(struct ib_device *device); const struct uapi_definition *chain; const struct uverbs_object_def *chain_obj_tree; + size_t needs_fn_offset; }; }; +/* + * Object is only supported if the function pointer named ibdev_fn in struct + * ib_device is not NULL. + */ +#define UAPI_DEF_OBJ_NEEDS_FN(ibdev_fn) \ + { \ + .kind = UAPI_DEF_IS_SUPPORTED_DEV_FN, \ + .scope = UAPI_SCOPE_OBJECT, \ + .needs_fn_offset = \ + offsetof(struct ib_device, ibdev_fn) + \ + BUILD_BUG_ON_ZERO( \ + sizeof(((struct ib_device *)0)->ibdev_fn) != \ + sizeof(void *)), \ + } + +/* Call a function to determine if the entire object is supported or not */ +#define UAPI_DEF_IS_OBJ_SUPPORTED(_func) \ + { \ + .kind = UAPI_DEF_IS_SUPPORTED_FUNC, \ + .scope = UAPI_SCOPE_OBJECT, .func_is_supported = _func, \ + } + /* Include another struct uapi_definition in this one */ #define UAPI_DEF_CHAIN(_def_var) \ { \ -- 2.7.4