/* * Copyright (c) 2017, Mellanox Technologies inc. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * 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 _UVERBS_IOCTL_ #define _UVERBS_IOCTL_ #include #include #include #include #include /* * ======================================= * Verbs action specifications * ======================================= */ enum uverbs_attr_type { UVERBS_ATTR_TYPE_NA, UVERBS_ATTR_TYPE_PTR_IN, UVERBS_ATTR_TYPE_PTR_OUT, UVERBS_ATTR_TYPE_IDR, UVERBS_ATTR_TYPE_FD, UVERBS_ATTR_TYPE_ENUM_IN, }; enum uverbs_obj_access { UVERBS_ACCESS_READ, UVERBS_ACCESS_WRITE, UVERBS_ACCESS_NEW, UVERBS_ACCESS_DESTROY }; /* Specification of a single attribute inside the ioctl message */ /* good size 16 */ struct uverbs_attr_spec { u8 type; /* * Support extending attributes by length. Allow the user to provide * more bytes than ptr.len, but check that everything after is zero'd * by the user. */ u8 zero_trailing:1; /* * Valid only for PTR_IN. Allocate and copy the data inside * the parser */ u8 alloc_and_copy:1; u8 mandatory:1; union { struct { /* Current known size to kernel */ u16 len; /* User isn't allowed to provide something < min_len */ u16 min_len; } ptr; struct { /* * higher bits mean the namespace and lower bits mean * the type id within the namespace. */ u16 obj_type; u8 access; } obj; struct { u8 num_elems; } enum_def; } u; /* This weird split of the enum lets us remove some padding */ union { struct { /* * The enum attribute can select one of the attributes * contained in the ids array. Currently only PTR_IN * attributes are supported in the ids array. */ const struct uverbs_attr_spec *ids; } enum_def; } u2; }; struct uverbs_attr_spec_hash { size_t num_attrs; unsigned long *mandatory_attrs_bitmask; struct uverbs_attr_spec attrs[0]; }; struct uverbs_attr_bundle; struct ib_uverbs_file; struct uverbs_method_spec { /* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */ u32 flags; size_t num_buckets; size_t num_child_attrs; int (*handler)(struct ib_uverbs_file *ufile, struct uverbs_attr_bundle *ctx); struct uverbs_attr_spec_hash *attr_buckets[0]; }; struct uverbs_method_spec_hash { size_t num_methods; struct uverbs_method_spec *methods[0]; }; struct uverbs_object_spec { const struct uverbs_obj_type *type_attrs; size_t num_buckets; struct uverbs_method_spec_hash *method_buckets[0]; }; struct uverbs_object_spec_hash { size_t num_objects; struct uverbs_object_spec *objects[0]; }; struct uverbs_root_spec { size_t num_buckets; struct uverbs_object_spec_hash *object_buckets[0]; }; /* * Information about the API is loaded into a radix tree. For IOCTL we start * with a tuple of: * object_id, attr_id, method_id * * Which is a 48 bit value, with most of the bits guaranteed to be zero. Based * on the current kernel support this is compressed into 16 bit key for the * radix tree. Since this compression is entirely internal to the kernel the * below limits can be revised if the kernel gains additional data. * * With 64 leafs per node this is a 3 level radix tree. * * The tree encodes multiple types, and uses a scheme where OBJ_ID,0,0 returns * the object slot, and OBJ_ID,METH_ID,0 and returns the method slot. */ enum uapi_radix_data { UVERBS_API_NS_FLAG = 1U << UVERBS_ID_NS_SHIFT, UVERBS_API_ATTR_KEY_BITS = 6, UVERBS_API_ATTR_KEY_MASK = GENMASK(UVERBS_API_ATTR_KEY_BITS - 1, 0), UVERBS_API_ATTR_BKEY_LEN = (1 << UVERBS_API_ATTR_KEY_BITS) - 1, UVERBS_API_METHOD_KEY_BITS = 5, UVERBS_API_METHOD_KEY_SHIFT = UVERBS_API_ATTR_KEY_BITS, UVERBS_API_METHOD_KEY_NUM_CORE = 24, UVERBS_API_METHOD_KEY_NUM_DRIVER = (1 << UVERBS_API_METHOD_KEY_BITS) - UVERBS_API_METHOD_KEY_NUM_CORE, UVERBS_API_METHOD_KEY_MASK = GENMASK( UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT - 1, UVERBS_API_METHOD_KEY_SHIFT), UVERBS_API_OBJ_KEY_BITS = 5, UVERBS_API_OBJ_KEY_SHIFT = UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT, UVERBS_API_OBJ_KEY_NUM_CORE = 24, UVERBS_API_OBJ_KEY_NUM_DRIVER = (1 << UVERBS_API_OBJ_KEY_BITS) - UVERBS_API_OBJ_KEY_NUM_CORE, UVERBS_API_OBJ_KEY_MASK = GENMASK(31, UVERBS_API_OBJ_KEY_SHIFT), /* This id guaranteed to not exist in the radix tree */ UVERBS_API_KEY_ERR = 0xFFFFFFFF, }; static inline __attribute_const__ u32 uapi_key_obj(u32 id) { if (id & UVERBS_API_NS_FLAG) { id &= ~UVERBS_API_NS_FLAG; if (id >= UVERBS_API_OBJ_KEY_NUM_DRIVER) return UVERBS_API_KEY_ERR; id = id + UVERBS_API_OBJ_KEY_NUM_CORE; } else { if (id >= UVERBS_API_OBJ_KEY_NUM_CORE) return UVERBS_API_KEY_ERR; } return id << UVERBS_API_OBJ_KEY_SHIFT; } static inline __attribute_const__ bool uapi_key_is_object(u32 key) { return (key & ~UVERBS_API_OBJ_KEY_MASK) == 0; } static inline __attribute_const__ u32 uapi_key_ioctl_method(u32 id) { if (id & UVERBS_API_NS_FLAG) { id &= ~UVERBS_API_NS_FLAG; if (id >= UVERBS_API_METHOD_KEY_NUM_DRIVER) return UVERBS_API_KEY_ERR; id = id + UVERBS_API_METHOD_KEY_NUM_CORE; } else { id++; if (id >= UVERBS_API_METHOD_KEY_NUM_CORE) return UVERBS_API_KEY_ERR; } return id << UVERBS_API_METHOD_KEY_SHIFT; } static inline __attribute_const__ u32 uapi_key_attr_to_method(u32 attr_key) { return attr_key & (UVERBS_API_OBJ_KEY_MASK | UVERBS_API_METHOD_KEY_MASK); } static inline __attribute_const__ bool uapi_key_is_ioctl_method(u32 key) { return (key & UVERBS_API_METHOD_KEY_MASK) != 0 && (key & UVERBS_API_ATTR_KEY_MASK) == 0; } static inline __attribute_const__ u32 uapi_key_attrs_start(u32 ioctl_method_key) { /* 0 is the method slot itself */ return ioctl_method_key + 1; } static inline __attribute_const__ u32 uapi_key_attr(u32 id) { /* * The attr is designed to fit in the typical single radix tree node * of 64 entries. Since allmost all methods have driver attributes we * organize things so that the driver and core attributes interleave to * reduce the length of the attributes array in typical cases. */ if (id & UVERBS_API_NS_FLAG) { id &= ~UVERBS_API_NS_FLAG; id++; if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1)) return UVERBS_API_KEY_ERR; id = (id << 1) | 0; } else { if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1)) return UVERBS_API_KEY_ERR; id = (id << 1) | 1; } return id; } static inline __attribute_const__ bool uapi_key_is_attr(u32 key) { return (key & UVERBS_API_METHOD_KEY_MASK) != 0 && (key & UVERBS_API_ATTR_KEY_MASK) != 0; } /* * This returns a value in the range [0 to UVERBS_API_ATTR_BKEY_LEN), * basically it undoes the reservation of 0 in the ID numbering. attr_key * must already be masked with UVERBS_API_ATTR_KEY_MASK, or be the output of * uapi_key_attr(). */ static inline __attribute_const__ u32 uapi_bkey_attr(u32 attr_key) { return attr_key - 1; } /* * ======================================= * Verbs definitions * ======================================= */ struct uverbs_attr_def { u16 id; struct uverbs_attr_spec attr; }; struct uverbs_method_def { u16 id; /* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */ u32 flags; size_t num_attrs; const struct uverbs_attr_def * const (*attrs)[]; int (*handler)(struct ib_uverbs_file *ufile, struct uverbs_attr_bundle *ctx); }; struct uverbs_object_def { u16 id; const struct uverbs_obj_type *type_attrs; size_t num_methods; const struct uverbs_method_def * const (*methods)[]; }; struct uverbs_object_tree_def { size_t num_objects; const struct uverbs_object_def * const (*objects)[]; }; /* * ======================================= * Attribute Specifications * ======================================= */ #define UVERBS_ATTR_SIZE(_min_len, _len) \ .u.ptr.min_len = _min_len, .u.ptr.len = _len #define UVERBS_ATTR_NO_DATA() UVERBS_ATTR_SIZE(0, 0) /* * Specifies a uapi structure that cannot be extended. The user must always * supply the whole structure and nothing more. The structure must be declared * in a header under include/uapi/rdma. */ #define UVERBS_ATTR_TYPE(_type) \ .u.ptr.min_len = sizeof(_type), .u.ptr.len = sizeof(_type) /* * Specifies a uapi structure where the user must provide at least up to * member 'last'. Anything after last and up until the end of the structure * can be non-zero, anything longer than the end of the structure must be * zero. The structure must be declared in a header under include/uapi/rdma. */ #define UVERBS_ATTR_STRUCT(_type, _last) \ .zero_trailing = 1, \ UVERBS_ATTR_SIZE(((uintptr_t)(&((_type *)0)->_last + 1)), \ sizeof(_type)) /* * Specifies at least min_len bytes must be passed in, but the amount can be * larger, up to the protocol maximum size. No check for zeroing is done. */ #define UVERBS_ATTR_MIN_SIZE(_min_len) UVERBS_ATTR_SIZE(_min_len, USHRT_MAX) /* Must be used in the '...' of any UVERBS_ATTR */ #define UA_ALLOC_AND_COPY .alloc_and_copy = 1 #define UA_MANDATORY .mandatory = 1 #define UA_OPTIONAL .mandatory = 0 #define UVERBS_ATTR_IDR(_attr_id, _idr_type, _access, ...) \ (&(const struct uverbs_attr_def){ \ .id = _attr_id, \ .attr = { .type = UVERBS_ATTR_TYPE_IDR, \ .u.obj.obj_type = _idr_type, \ .u.obj.access = _access, \ __VA_ARGS__ } }) #define UVERBS_ATTR_FD(_attr_id, _fd_type, _access, ...) \ (&(const struct uverbs_attr_def){ \ .id = (_attr_id) + \ BUILD_BUG_ON_ZERO((_access) != UVERBS_ACCESS_NEW && \ (_access) != UVERBS_ACCESS_READ), \ .attr = { .type = UVERBS_ATTR_TYPE_FD, \ .u.obj.obj_type = _fd_type, \ .u.obj.access = _access, \ __VA_ARGS__ } }) #define UVERBS_ATTR_PTR_IN(_attr_id, _type, ...) \ (&(const struct uverbs_attr_def){ \ .id = _attr_id, \ .attr = { .type = UVERBS_ATTR_TYPE_PTR_IN, \ _type, \ __VA_ARGS__ } }) #define UVERBS_ATTR_PTR_OUT(_attr_id, _type, ...) \ (&(const struct uverbs_attr_def){ \ .id = _attr_id, \ .attr = { .type = UVERBS_ATTR_TYPE_PTR_OUT, \ _type, \ __VA_ARGS__ } }) /* _enum_arry should be a 'static const union uverbs_attr_spec[]' */ #define UVERBS_ATTR_ENUM_IN(_attr_id, _enum_arr, ...) \ (&(const struct uverbs_attr_def){ \ .id = _attr_id, \ .attr = { .type = UVERBS_ATTR_TYPE_ENUM_IN, \ .u2.enum_def.ids = _enum_arr, \ .u.enum_def.num_elems = ARRAY_SIZE(_enum_arr), \ __VA_ARGS__ }, \ }) /* * An input value that is a bitwise combination of values of _enum_type. * This permits the flag value to be passed as either a u32 or u64, it must * be retrieved via uverbs_get_flag(). */ #define UVERBS_ATTR_FLAGS_IN(_attr_id, _enum_type, ...) \ UVERBS_ATTR_PTR_IN( \ _attr_id, \ UVERBS_ATTR_SIZE(sizeof(u32) + BUILD_BUG_ON_ZERO( \ !sizeof(_enum_type *)), \ sizeof(u64)), \ __VA_ARGS__) /* * This spec is used in order to pass information to the hardware driver in a * legacy way. Every verb that could get driver specific data should get this * spec. */ #define UVERBS_ATTR_UHW() \ UVERBS_ATTR_PTR_IN(UVERBS_ATTR_UHW_IN, \ UVERBS_ATTR_MIN_SIZE(0), \ UA_OPTIONAL), \ UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT, \ UVERBS_ATTR_MIN_SIZE(0), \ UA_OPTIONAL) /* * ======================================= * Declaration helpers * ======================================= */ #define DECLARE_UVERBS_OBJECT_TREE(_name, ...) \ static const struct uverbs_object_def *const _name##_ptr[] = { \ __VA_ARGS__, \ }; \ static const struct uverbs_object_tree_def _name = { \ .num_objects = ARRAY_SIZE(_name##_ptr), \ .objects = &_name##_ptr, \ } /* ================================================= * Parsing infrastructure * ================================================= */ struct uverbs_ptr_attr { /* * If UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY is set then the 'ptr' is * used. */ union { void *ptr; u64 data; }; u16 len; /* Combination of bits from enum UVERBS_ATTR_F_XXXX */ u16 flags; u8 enum_id; }; struct uverbs_obj_attr { struct ib_uobject *uobject; }; struct uverbs_attr { /* * pointer to the user-space given attribute, in order to write the * new uobject's id or update flags. */ struct ib_uverbs_attr __user *uattr; union { struct uverbs_ptr_attr ptr_attr; struct uverbs_obj_attr obj_attr; }; }; struct uverbs_attr_bundle_hash { /* if bit i is set, it means attrs[i] contains valid information */ unsigned long *valid_bitmap; size_t num_attrs; /* * arrays of attributes, each element corresponds to the specification * of the attribute in the same index. */ struct uverbs_attr *attrs; }; struct uverbs_attr_bundle { struct ib_uverbs_file *ufile; size_t num_buckets; struct uverbs_attr_bundle_hash hash[]; }; static inline bool uverbs_attr_is_valid_in_hash(const struct uverbs_attr_bundle_hash *attrs_hash, unsigned int idx) { return test_bit(idx, attrs_hash->valid_bitmap); } static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle, unsigned int idx) { u16 idx_bucket = idx >> UVERBS_ID_NS_SHIFT; if (attrs_bundle->num_buckets <= idx_bucket) return false; return uverbs_attr_is_valid_in_hash(&attrs_bundle->hash[idx_bucket], idx & ~UVERBS_ID_NS_MASK); } #define IS_UVERBS_COPY_ERR(_ret) ((_ret) && (_ret) != -ENOENT) static inline const struct uverbs_attr *uverbs_attr_get(const struct uverbs_attr_bundle *attrs_bundle, u16 idx) { u16 idx_bucket = idx >> UVERBS_ID_NS_SHIFT; if (!uverbs_attr_is_valid(attrs_bundle, idx)) return ERR_PTR(-ENOENT); return &attrs_bundle->hash[idx_bucket].attrs[idx & ~UVERBS_ID_NS_MASK]; } static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle, u16 idx) { const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx); if (IS_ERR(attr)) return PTR_ERR(attr); return attr->ptr_attr.enum_id; } static inline void *uverbs_attr_get_obj(const struct uverbs_attr_bundle *attrs_bundle, u16 idx) { const struct uverbs_attr *attr; attr = uverbs_attr_get(attrs_bundle, idx); if (IS_ERR(attr)) return ERR_CAST(attr); return attr->obj_attr.uobject->object; } static inline struct ib_uobject *uverbs_attr_get_uobject(const struct uverbs_attr_bundle *attrs_bundle, u16 idx) { const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx); if (IS_ERR(attr)) return ERR_CAST(attr); return attr->obj_attr.uobject; } static inline int uverbs_attr_get_len(const struct uverbs_attr_bundle *attrs_bundle, u16 idx) { const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx); if (IS_ERR(attr)) return PTR_ERR(attr); return attr->ptr_attr.len; } static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle, size_t idx, const void *from, size_t size) { const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx); u16 flags; size_t min_size; if (IS_ERR(attr)) return PTR_ERR(attr); min_size = min_t(size_t, attr->ptr_attr.len, size); if (copy_to_user(u64_to_user_ptr(attr->ptr_attr.data), from, min_size)) return -EFAULT; flags = attr->ptr_attr.flags | UVERBS_ATTR_F_VALID_OUTPUT; if (put_user(flags, &attr->uattr->flags)) return -EFAULT; return 0; } static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr) { return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data); } static inline void *uverbs_attr_get_alloced_ptr( const struct uverbs_attr_bundle *attrs_bundle, u16 idx) { const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx); if (IS_ERR(attr)) return (void *)attr; return uverbs_attr_ptr_is_inline(attr) ? (void *)&attr->ptr_attr.data : attr->ptr_attr.ptr; } static inline int _uverbs_copy_from(void *to, const struct uverbs_attr_bundle *attrs_bundle, size_t idx, size_t size) { const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx); if (IS_ERR(attr)) return PTR_ERR(attr); /* * Validation ensures attr->ptr_attr.len >= size. If the caller is * using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call * uverbs_copy_from_or_zero. */ if (unlikely(size < attr->ptr_attr.len)) return -EINVAL; if (uverbs_attr_ptr_is_inline(attr)) memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len); else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data), attr->ptr_attr.len)) return -EFAULT; return 0; } static inline int _uverbs_copy_from_or_zero(void *to, const struct uverbs_attr_bundle *attrs_bundle, size_t idx, size_t size) { const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx); size_t min_size; if (IS_ERR(attr)) return PTR_ERR(attr); min_size = min_t(size_t, size, attr->ptr_attr.len); if (uverbs_attr_ptr_is_inline(attr)) memcpy(to, &attr->ptr_attr.data, min_size); else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data), min_size)) return -EFAULT; if (size > min_size) memset(to + min_size, 0, size - min_size); return 0; } #define uverbs_copy_from(to, attrs_bundle, idx) \ _uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to)) #define uverbs_copy_from_or_zero(to, attrs_bundle, idx) \ _uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to)) #if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS) int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle, size_t idx, u64 allowed_bits); int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle, size_t idx, u64 allowed_bits); #else static inline int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle, size_t idx, u64 allowed_bits) { return -EINVAL; } static inline int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle, size_t idx, u64 allowed_bits) { return -EINVAL; } #endif /* ================================================= * Definitions -> Specs infrastructure * ================================================= */ /* * uverbs_alloc_spec_tree - Merges different common and driver specific feature * into one parsing tree that every uverbs command will be parsed upon. * * @num_trees: Number of trees in the array @trees. * @trees: Array of pointers to tree root definitions to merge. Each such tree * possibly contains objects, methods and attributes definitions. * * Returns: * uverbs_root_spec *: The root of the merged parsing tree. * On error, we return an error code. Error is checked via IS_ERR. * * The following merges could take place: * a. Two trees representing the same method with different handler * -> We take the handler of the tree that its handler != NULL * and its index in the trees array is greater. The incentive for that * is that developers are expected to first merge common trees and then * merge trees that gives specialized the behaviour. * b. Two trees representing the same object with different * type_attrs (struct uverbs_obj_type): * -> We take the type_attrs of the tree that its type_attr != NULL * and its index in the trees array is greater. This could be used * in order to override the free function, allocation size, etc. * c. Two trees representing the same method attribute (same id but possibly * different attributes): * -> ERROR (-ENOENT), we believe that's not the programmer's intent. * * An object without any methods is considered invalid and will abort the * function with -ENOENT error. */ #if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS) struct uverbs_root_spec *uverbs_alloc_spec_tree(unsigned int num_trees, const struct uverbs_object_tree_def **trees); void uverbs_free_spec_tree(struct uverbs_root_spec *root); #else static inline struct uverbs_root_spec *uverbs_alloc_spec_tree(unsigned int num_trees, const struct uverbs_object_tree_def **trees) { return NULL; } static inline void uverbs_free_spec_tree(struct uverbs_root_spec *root) { } #endif #endif