include/rdma/uverbs_ioctl.h

   1 /*
   2  * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #ifndef _UVERBS_IOCTL_
  34 #define _UVERBS_IOCTL_
  35
  36 #include <rdma/uverbs_types.h>
  37 #include <linux/uaccess.h>
  38 #include <rdma/rdma_user_ioctl.h>
  39 #include <rdma/ib_user_ioctl_verbs.h>
  40 #include <rdma/ib_user_ioctl_cmds.h>
  41
  42 /*
  43  * =======================================
  44  *      Verbs action specifications
  45  * =======================================
  46  */
  47
  48 enum uverbs_attr_type {
  49         UVERBS_ATTR_TYPE_NA,
  50         UVERBS_ATTR_TYPE_PTR_IN,
  51         UVERBS_ATTR_TYPE_PTR_OUT,
  52         UVERBS_ATTR_TYPE_IDR,
  53         UVERBS_ATTR_TYPE_FD,
  54         UVERBS_ATTR_TYPE_ENUM_IN,
  55         UVERBS_ATTR_TYPE_IDRS_ARRAY,
  56 };
  57
  58 enum uverbs_obj_access {
  59         UVERBS_ACCESS_READ,
  60         UVERBS_ACCESS_WRITE,
  61         UVERBS_ACCESS_NEW,
  62         UVERBS_ACCESS_DESTROY
  63 };
  64
  65 /* Specification of a single attribute inside the ioctl message */
  66 /* good size 16 */
  67 struct uverbs_attr_spec {
  68         u8 type;
  69
  70         /*
  71          * Support extending attributes by length. Allow the user to provide
  72          * more bytes than ptr.len, but check that everything after is zero'd
  73          * by the user.
  74          */
  75         u8 zero_trailing:1;
  76         /*
  77          * Valid only for PTR_IN. Allocate and copy the data inside
  78          * the parser
  79          */
  80         u8 alloc_and_copy:1;
  81         u8 mandatory:1;
  82         /* True if this is from UVERBS_ATTR_UHW */
  83         u8 is_udata:1;
  84
  85         union {
  86                 struct {
  87                         /* Current known size to kernel */
  88                         u16 len;
  89                         /* User isn't allowed to provide something < min_len */
  90                         u16 min_len;
  91                 } ptr;
  92
  93                 struct {
  94                         /*
  95                          * higher bits mean the namespace and lower bits mean
  96                          * the type id within the namespace.
  97                          */
  98                         u16 obj_type;
  99                         u8 access;
 100                 } obj;
 101
 102                 struct {
 103                         u8 num_elems;
 104                 } enum_def;
 105         } u;
 106
 107         /* This weird split lets us remove some padding */
 108         union {
 109                 struct {
 110                         /*
 111                          * The enum attribute can select one of the attributes
 112                          * contained in the ids array. Currently only PTR_IN
 113                          * attributes are supported in the ids array.
 114                          */
 115                         const struct uverbs_attr_spec *ids;
 116                 } enum_def;
 117
 118                 struct {
 119                         /*
 120                          * higher bits mean the namespace and lower bits mean
 121                          * the type id within the namespace.
 122                          */
 123                         u16                             obj_type;
 124                         u16                             min_len;
 125                         u16                             max_len;
 126                         u8                              access;
 127                 } objs_arr;
 128         } u2;
 129 };
 130
 131 /*
 132  * Information about the API is loaded into a radix tree. For IOCTL we start
 133  * with a tuple of:
 134  *  object_id, attr_id, method_id
 135  *
 136  * Which is a 48 bit value, with most of the bits guaranteed to be zero. Based
 137  * on the current kernel support this is compressed into 16 bit key for the
 138  * radix tree. Since this compression is entirely internal to the kernel the
 139  * below limits can be revised if the kernel gains additional data.
 140  *
 141  * With 64 leafs per node this is a 3 level radix tree.
 142  *
 143  * The tree encodes multiple types, and uses a scheme where OBJ_ID,0,0 returns
 144  * the object slot, and OBJ_ID,METH_ID,0 and returns the method slot.
 145  *
 146  * This also encodes the tables for the write() and write() extended commands
 147  * using the coding
 148  *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE,command #
 149  *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE_EX,command_ex #
 150  * ie the WRITE path is treated as a special method type in the ioctl
 151  * framework.
 152  */
 153 enum uapi_radix_data {
 154         UVERBS_API_NS_FLAG = 1U << UVERBS_ID_NS_SHIFT,
 155
 156         UVERBS_API_ATTR_KEY_BITS = 6,
 157         UVERBS_API_ATTR_KEY_MASK = GENMASK(UVERBS_API_ATTR_KEY_BITS - 1, 0),
 158         UVERBS_API_ATTR_BKEY_LEN = (1 << UVERBS_API_ATTR_KEY_BITS) - 1,
 159         UVERBS_API_WRITE_KEY_NUM = 1 << UVERBS_API_ATTR_KEY_BITS,
 160
 161         UVERBS_API_METHOD_KEY_BITS = 5,
 162         UVERBS_API_METHOD_KEY_SHIFT = UVERBS_API_ATTR_KEY_BITS,
 163         UVERBS_API_METHOD_KEY_NUM_CORE = 22,
 164         UVERBS_API_METHOD_IS_WRITE = 30 << UVERBS_API_METHOD_KEY_SHIFT,
 165         UVERBS_API_METHOD_IS_WRITE_EX = 31 << UVERBS_API_METHOD_KEY_SHIFT,
 166         UVERBS_API_METHOD_KEY_NUM_DRIVER =
 167                 (UVERBS_API_METHOD_IS_WRITE >> UVERBS_API_METHOD_KEY_SHIFT) -
 168                 UVERBS_API_METHOD_KEY_NUM_CORE,
 169         UVERBS_API_METHOD_KEY_MASK = GENMASK(
 170                 UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT - 1,
 171                 UVERBS_API_METHOD_KEY_SHIFT),
 172
 173         UVERBS_API_OBJ_KEY_BITS = 5,
 174         UVERBS_API_OBJ_KEY_SHIFT =
 175                 UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT,
 176         UVERBS_API_OBJ_KEY_NUM_CORE = 24,
 177         UVERBS_API_OBJ_KEY_NUM_DRIVER =
 178                 (1 << UVERBS_API_OBJ_KEY_BITS) - UVERBS_API_OBJ_KEY_NUM_CORE,
 179         UVERBS_API_OBJ_KEY_MASK = GENMASK(31, UVERBS_API_OBJ_KEY_SHIFT),
 180
 181         /* This id guaranteed to not exist in the radix tree */
 182         UVERBS_API_KEY_ERR = 0xFFFFFFFF,
 183 };
 184
 185 static inline __attribute_const__ u32 uapi_key_obj(u32 id)
 186 {
 187         if (id & UVERBS_API_NS_FLAG) {
 188                 id &= ~UVERBS_API_NS_FLAG;
 189                 if (id >= UVERBS_API_OBJ_KEY_NUM_DRIVER)
 190                         return UVERBS_API_KEY_ERR;
 191                 id = id + UVERBS_API_OBJ_KEY_NUM_CORE;
 192         } else {
 193                 if (id >= UVERBS_API_OBJ_KEY_NUM_CORE)
 194                         return UVERBS_API_KEY_ERR;
 195         }
 196
 197         return id << UVERBS_API_OBJ_KEY_SHIFT;
 198 }
 199
 200 static inline __attribute_const__ bool uapi_key_is_object(u32 key)
 201 {
 202         return (key & ~UVERBS_API_OBJ_KEY_MASK) == 0;
 203 }
 204
 205 static inline __attribute_const__ u32 uapi_key_ioctl_method(u32 id)
 206 {
 207         if (id & UVERBS_API_NS_FLAG) {
 208                 id &= ~UVERBS_API_NS_FLAG;
 209                 if (id >= UVERBS_API_METHOD_KEY_NUM_DRIVER)
 210                         return UVERBS_API_KEY_ERR;
 211                 id = id + UVERBS_API_METHOD_KEY_NUM_CORE;
 212         } else {
 213                 id++;
 214                 if (id >= UVERBS_API_METHOD_KEY_NUM_CORE)
 215                         return UVERBS_API_KEY_ERR;
 216         }
 217
 218         return id << UVERBS_API_METHOD_KEY_SHIFT;
 219 }
 220
 221 static inline __attribute_const__ u32 uapi_key_write_method(u32 id)
 222 {
 223         if (id >= UVERBS_API_WRITE_KEY_NUM)
 224                 return UVERBS_API_KEY_ERR;
 225         return UVERBS_API_METHOD_IS_WRITE | id;
 226 }
 227
 228 static inline __attribute_const__ u32 uapi_key_write_ex_method(u32 id)
 229 {
 230         if (id >= UVERBS_API_WRITE_KEY_NUM)
 231                 return UVERBS_API_KEY_ERR;
 232         return UVERBS_API_METHOD_IS_WRITE_EX | id;
 233 }
 234
 235 static inline __attribute_const__ u32
 236 uapi_key_attr_to_ioctl_method(u32 attr_key)
 237 {
 238         return attr_key &
 239                (UVERBS_API_OBJ_KEY_MASK | UVERBS_API_METHOD_KEY_MASK);
 240 }
 241
 242 static inline __attribute_const__ bool uapi_key_is_ioctl_method(u32 key)
 243 {
 244         unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;
 245
 246         return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
 247                (key & UVERBS_API_ATTR_KEY_MASK) == 0;
 248 }
 249
 250 static inline __attribute_const__ bool uapi_key_is_write_method(u32 key)
 251 {
 252         return (key & UVERBS_API_METHOD_KEY_MASK) == UVERBS_API_METHOD_IS_WRITE;
 253 }
 254
 255 static inline __attribute_const__ bool uapi_key_is_write_ex_method(u32 key)
 256 {
 257         return (key & UVERBS_API_METHOD_KEY_MASK) ==
 258                UVERBS_API_METHOD_IS_WRITE_EX;
 259 }
 260
 261 static inline __attribute_const__ u32 uapi_key_attrs_start(u32 ioctl_method_key)
 262 {
 263         /* 0 is the method slot itself */
 264         return ioctl_method_key + 1;
 265 }
 266
 267 static inline __attribute_const__ u32 uapi_key_attr(u32 id)
 268 {
 269         /*
 270          * The attr is designed to fit in the typical single radix tree node
 271          * of 64 entries. Since allmost all methods have driver attributes we
 272          * organize things so that the driver and core attributes interleave to
 273          * reduce the length of the attributes array in typical cases.
 274          */
 275         if (id & UVERBS_API_NS_FLAG) {
 276                 id &= ~UVERBS_API_NS_FLAG;
 277                 id++;
 278                 if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
 279                         return UVERBS_API_KEY_ERR;
 280                 id = (id << 1) | 0;
 281         } else {
 282                 if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
 283                         return UVERBS_API_KEY_ERR;
 284                 id = (id << 1) | 1;
 285         }
 286
 287         return id;
 288 }
 289
 290 /* Only true for ioctl methods */
 291 static inline __attribute_const__ bool uapi_key_is_attr(u32 key)
 292 {
 293         unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;
 294
 295         return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
 296                (key & UVERBS_API_ATTR_KEY_MASK) != 0;
 297 }
 298
 299 /*
 300  * This returns a value in the range [0 to UVERBS_API_ATTR_BKEY_LEN),
 301  * basically it undoes the reservation of 0 in the ID numbering. attr_key
 302  * must already be masked with UVERBS_API_ATTR_KEY_MASK, or be the output of
 303  * uapi_key_attr().
 304  */
 305 static inline __attribute_const__ u32 uapi_bkey_attr(u32 attr_key)
 306 {
 307         return attr_key - 1;
 308 }
 309
 310 static inline __attribute_const__ u32 uapi_bkey_to_key_attr(u32 attr_bkey)
 311 {
 312         return attr_bkey + 1;
 313 }
 314
 315 /*
 316  * =======================================
 317  *      Verbs definitions
 318  * =======================================
 319  */
 320
 321 struct uverbs_attr_def {
 322         u16                           id;
 323         struct uverbs_attr_spec       attr;
 324 };
 325
 326 struct uverbs_method_def {
 327         u16                                  id;
 328         /* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
 329         u32                                  flags;
 330         size_t                               num_attrs;
 331         const struct uverbs_attr_def * const (*attrs)[];
 332         int (*handler)(struct uverbs_attr_bundle *attrs);
 333 };
 334
 335 struct uverbs_object_def {
 336         u16                                      id;
 337         const struct uverbs_obj_type            *type_attrs;
 338         size_t                                   num_methods;
 339         const struct uverbs_method_def * const (*methods)[];
 340 };
 341
 342 enum uapi_definition_kind {
 343         UAPI_DEF_END = 0,
 344         UAPI_DEF_OBJECT_START,
 345         UAPI_DEF_WRITE,
 346         UAPI_DEF_CHAIN_OBJ_TREE,
 347         UAPI_DEF_CHAIN,
 348         UAPI_DEF_IS_SUPPORTED_FUNC,
 349         UAPI_DEF_IS_SUPPORTED_DEV_FN,
 350 };
 351
 352 enum uapi_definition_scope {
 353         UAPI_SCOPE_OBJECT = 1,
 354         UAPI_SCOPE_METHOD = 2,
 355 };
 356
 357 struct uapi_definition {
 358         u8 kind;
 359         u8 scope;
 360         union {
 361                 struct {
 362                         u16 object_id;
 363                 } object_start;
 364                 struct {
 365                         u16 command_num;
 366                         u8 is_ex:1;
 367                         u8 has_udata:1;
 368                         u8 has_resp:1;
 369                         u8 req_size;
 370                         u8 resp_size;
 371                 } write;
 372         };
 373
 374         union {
 375                 bool (*func_is_supported)(struct ib_device *device);
 376                 int (*func_write)(struct uverbs_attr_bundle *attrs);
 377                 const struct uapi_definition *chain;
 378                 const struct uverbs_object_def *chain_obj_tree;
 379                 size_t needs_fn_offset;
 380         };
 381 };
 382
 383 /* Define things connected to object_id */
 384 #define DECLARE_UVERBS_OBJECT(_object_id, ...)                                 \
 385         {                                                                      \
 386                 .kind = UAPI_DEF_OBJECT_START,                                 \
 387                 .object_start = { .object_id = _object_id },                   \
 388         },                                                                     \
 389                 ##__VA_ARGS__
 390
 391 /* Use in a var_args of DECLARE_UVERBS_OBJECT */
 392 #define DECLARE_UVERBS_WRITE(_command_num, _func, _cmd_desc, ...)              \
 393         {                                                                      \
 394                 .kind = UAPI_DEF_WRITE,                                        \
 395                 .scope = UAPI_SCOPE_OBJECT,                                    \
 396                 .write = { .is_ex = 0, .command_num = _command_num },          \
 397                 .func_write = _func,                                           \
 398                 _cmd_desc,                                                     \
 399         },                                                                     \
 400                 ##__VA_ARGS__
 401
 402 /* Use in a var_args of DECLARE_UVERBS_OBJECT */
 403 #define DECLARE_UVERBS_WRITE_EX(_command_num, _func, _cmd_desc, ...)           \
 404         {                                                                      \
 405                 .kind = UAPI_DEF_WRITE,                                        \
 406                 .scope = UAPI_SCOPE_OBJECT,                                    \
 407                 .write = { .is_ex = 1, .command_num = _command_num },          \
 408                 .func_write = _func,                                           \
 409                 _cmd_desc,                                                     \
 410         },                                                                     \
 411                 ##__VA_ARGS__
 412
 413 /*
 414  * Object is only supported if the function pointer named ibdev_fn in struct
 415  * ib_device is not NULL.
 416  */
 417 #define UAPI_DEF_OBJ_NEEDS_FN(ibdev_fn)                                        \
 418         {                                                                      \
 419                 .kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
 420                 .scope = UAPI_SCOPE_OBJECT,                                    \
 421                 .needs_fn_offset =                                             \
 422                         offsetof(struct ib_device_ops, ibdev_fn) +             \
 423                         BUILD_BUG_ON_ZERO(                                     \
 424                             sizeof(((struct ib_device_ops *)0)->ibdev_fn) !=   \
 425                             sizeof(void *)),                                   \
 426         }
 427
 428 /*
 429  * Method is only supported if the function pointer named ibdev_fn in struct
 430  * ib_device is not NULL.
 431  */
 432 #define UAPI_DEF_METHOD_NEEDS_FN(ibdev_fn)                                     \
 433         {                                                                      \
 434                 .kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
 435                 .scope = UAPI_SCOPE_METHOD,                                    \
 436                 .needs_fn_offset =                                             \
 437                         offsetof(struct ib_device_ops, ibdev_fn) +             \
 438                         BUILD_BUG_ON_ZERO(                                     \
 439                             sizeof(((struct ib_device_ops *)0)->ibdev_fn) !=   \
 440                             sizeof(void *)),                                   \
 441         }
 442
 443 /* Call a function to determine if the entire object is supported or not */
 444 #define UAPI_DEF_IS_OBJ_SUPPORTED(_func)                                       \
 445         {                                                                      \
 446                 .kind = UAPI_DEF_IS_SUPPORTED_FUNC,                            \
 447                 .scope = UAPI_SCOPE_OBJECT, .func_is_supported = _func,        \
 448         }
 449
 450 /* Include another struct uapi_definition in this one */
 451 #define UAPI_DEF_CHAIN(_def_var)                                               \
 452         {                                                                      \
 453                 .kind = UAPI_DEF_CHAIN, .chain = _def_var,                     \
 454         }
 455
 456 /* Temporary until the tree base description is replaced */
 457 #define UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, _object_ptr, ...)                \
 458         {                                                                      \
 459                 .kind = UAPI_DEF_CHAIN_OBJ_TREE,                               \
 460                 .object_start = { .object_id = _object_enum },                 \
 461                 .chain_obj_tree = _object_ptr,                                 \
 462         },                                                                     \
 463                 ##__VA_ARGS__
 464 #define UAPI_DEF_CHAIN_OBJ_TREE_NAMED(_object_enum, ...)                       \
 465         UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, &UVERBS_OBJECT(_object_enum),    \
 466                                 ##__VA_ARGS__)
 467
 468 /*
 469  * =======================================
 470  *      Attribute Specifications
 471  * =======================================
 472  */
 473
 474 #define UVERBS_ATTR_SIZE(_min_len, _len)                        \
 475         .u.ptr.min_len = _min_len, .u.ptr.len = _len
 476
 477 #define UVERBS_ATTR_NO_DATA() UVERBS_ATTR_SIZE(0, 0)
 478
 479 /*
 480  * Specifies a uapi structure that cannot be extended. The user must always
 481  * supply the whole structure and nothing more. The structure must be declared
 482  * in a header under include/uapi/rdma.
 483  */
 484 #define UVERBS_ATTR_TYPE(_type)                                 \
 485         .u.ptr.min_len = sizeof(_type), .u.ptr.len = sizeof(_type)
 486 /*
 487  * Specifies a uapi structure where the user must provide at least up to
 488  * member 'last'.  Anything after last and up until the end of the structure
 489  * can be non-zero, anything longer than the end of the structure must be
 490  * zero. The structure must be declared in a header under include/uapi/rdma.
 491  */
 492 #define UVERBS_ATTR_STRUCT(_type, _last)                                       \
 493         .zero_trailing = 1,                                                    \
 494         UVERBS_ATTR_SIZE(((uintptr_t)(&((_type *)0)->_last + 1)),              \
 495                          sizeof(_type))
 496 /*
 497  * Specifies at least min_len bytes must be passed in, but the amount can be
 498  * larger, up to the protocol maximum size. No check for zeroing is done.
 499  */
 500 #define UVERBS_ATTR_MIN_SIZE(_min_len) UVERBS_ATTR_SIZE(_min_len, USHRT_MAX)
 501
 502 /* Must be used in the '...' of any UVERBS_ATTR */
 503 #define UA_ALLOC_AND_COPY .alloc_and_copy = 1
 504 #define UA_MANDATORY .mandatory = 1
 505 #define UA_OPTIONAL .mandatory = 0
 506
 507 /*
 508  * min_len must be bigger than 0 and _max_len must be smaller than 4095.  Only
 509  * READ\WRITE accesses are supported.
 510  */
 511 #define UVERBS_ATTR_IDRS_ARR(_attr_id, _idr_type, _access, _min_len, _max_len, \
 512                              ...)                                              \
 513         (&(const struct uverbs_attr_def){                                      \
 514                 .id = (_attr_id) +                                             \
 515                       BUILD_BUG_ON_ZERO((_min_len) == 0 ||                     \
 516                                         (_max_len) >                           \
 517                                                 PAGE_SIZE / sizeof(void *) ||  \
 518                                         (_min_len) > (_max_len) ||             \
 519                                         (_access) == UVERBS_ACCESS_NEW ||      \
 520                                         (_access) == UVERBS_ACCESS_DESTROY),   \
 521                 .attr = { .type = UVERBS_ATTR_TYPE_IDRS_ARRAY,                 \
 522                           .u2.objs_arr.obj_type = _idr_type,                   \
 523                           .u2.objs_arr.access = _access,                       \
 524                           .u2.objs_arr.min_len = _min_len,                     \
 525                           .u2.objs_arr.max_len = _max_len,                     \
 526                           __VA_ARGS__ } })
 527
 528 /*
 529  * Only for use with UVERBS_ATTR_IDR, allows any uobject type to be accepted,
 530  * the user must validate the type of the uobject instead.
 531  */
 532 #define UVERBS_IDR_ANY_OBJECT 0xFFFF
 533
 534 #define UVERBS_ATTR_IDR(_attr_id, _idr_type, _access, ...)                     \
 535         (&(const struct uverbs_attr_def){                                      \
 536                 .id = _attr_id,                                                \
 537                 .attr = { .type = UVERBS_ATTR_TYPE_IDR,                        \
 538                           .u.obj.obj_type = _idr_type,                         \
 539                           .u.obj.access = _access,                             \
 540                           __VA_ARGS__ } })
 541
 542 #define UVERBS_ATTR_FD(_attr_id, _fd_type, _access, ...)                       \
 543         (&(const struct uverbs_attr_def){                                      \
 544                 .id = (_attr_id) +                                             \
 545                       BUILD_BUG_ON_ZERO((_access) != UVERBS_ACCESS_NEW &&      \
 546                                         (_access) != UVERBS_ACCESS_READ),      \
 547                 .attr = { .type = UVERBS_ATTR_TYPE_FD,                         \
 548                           .u.obj.obj_type = _fd_type,                          \
 549                           .u.obj.access = _access,                             \
 550                           __VA_ARGS__ } })
 551
 552 #define UVERBS_ATTR_PTR_IN(_attr_id, _type, ...)                               \
 553         (&(const struct uverbs_attr_def){                                      \
 554                 .id = _attr_id,                                                \
 555                 .attr = { .type = UVERBS_ATTR_TYPE_PTR_IN,                     \
 556                           _type,                                               \
 557                           __VA_ARGS__ } })
 558
 559 #define UVERBS_ATTR_PTR_OUT(_attr_id, _type, ...)                              \
 560         (&(const struct uverbs_attr_def){                                      \
 561                 .id = _attr_id,                                                \
 562                 .attr = { .type = UVERBS_ATTR_TYPE_PTR_OUT,                    \
 563                           _type,                                               \
 564                           __VA_ARGS__ } })
 565
 566 /* _enum_arry should be a 'static const union uverbs_attr_spec[]' */
 567 #define UVERBS_ATTR_ENUM_IN(_attr_id, _enum_arr, ...)                          \
 568         (&(const struct uverbs_attr_def){                                      \
 569                 .id = _attr_id,                                                \
 570                 .attr = { .type = UVERBS_ATTR_TYPE_ENUM_IN,                    \
 571                           .u2.enum_def.ids = _enum_arr,                        \
 572                           .u.enum_def.num_elems = ARRAY_SIZE(_enum_arr),       \
 573                           __VA_ARGS__ },                                       \
 574         })
 575
 576 /* An input value that is a member in the enum _enum_type. */
 577 #define UVERBS_ATTR_CONST_IN(_attr_id, _enum_type, ...)                        \
 578         UVERBS_ATTR_PTR_IN(                                                    \
 579                 _attr_id,                                                      \
 580                 UVERBS_ATTR_SIZE(                                              \
 581                         sizeof(u64) + BUILD_BUG_ON_ZERO(!sizeof(_enum_type)),  \
 582                         sizeof(u64)),                                          \
 583                 __VA_ARGS__)
 584
 585 /*
 586  * An input value that is a bitwise combination of values of _enum_type.
 587  * This permits the flag value to be passed as either a u32 or u64, it must
 588  * be retrieved via uverbs_get_flag().
 589  */
 590 #define UVERBS_ATTR_FLAGS_IN(_attr_id, _enum_type, ...)                        \
 591         UVERBS_ATTR_PTR_IN(                                                    \
 592                 _attr_id,                                                      \
 593                 UVERBS_ATTR_SIZE(sizeof(u32) + BUILD_BUG_ON_ZERO(              \
 594                                                        !sizeof(_enum_type *)), \
 595                                  sizeof(u64)),                                 \
 596                 __VA_ARGS__)
 597
 598 /*
 599  * This spec is used in order to pass information to the hardware driver in a
 600  * legacy way. Every verb that could get driver specific data should get this
 601  * spec.
 602  */
 603 #define UVERBS_ATTR_UHW()                                                      \
 604         UVERBS_ATTR_PTR_IN(UVERBS_ATTR_UHW_IN,                                 \
 605                            UVERBS_ATTR_MIN_SIZE(0),                            \
 606                            UA_OPTIONAL,                                        \
 607                            .is_udata = 1),                                     \
 608         UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT,                               \
 609                             UVERBS_ATTR_MIN_SIZE(0),                           \
 610                             UA_OPTIONAL,                                       \
 611                             .is_udata = 1)
 612
 613 /* =================================================
 614  *              Parsing infrastructure
 615  * =================================================
 616  */
 617
 618
 619 struct uverbs_ptr_attr {
 620         /*
 621          * If UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY is set then the 'ptr' is
 622          * used.
 623          */
 624         union {
 625                 void *ptr;
 626                 u64 data;
 627         };
 628         u16             len;
 629         u16             uattr_idx;
 630         u8              enum_id;
 631 };
 632
 633 struct uverbs_obj_attr {
 634         struct ib_uobject               *uobject;
 635         const struct uverbs_api_attr    *attr_elm;
 636 };
 637
 638 struct uverbs_objs_arr_attr {
 639         struct ib_uobject **uobjects;
 640         u16 len;
 641 };
 642
 643 struct uverbs_attr {
 644         union {
 645                 struct uverbs_ptr_attr  ptr_attr;
 646                 struct uverbs_obj_attr  obj_attr;
 647                 struct uverbs_objs_arr_attr objs_arr_attr;
 648         };
 649 };
 650
 651 struct uverbs_attr_bundle {
 652         struct ib_udata driver_udata;
 653         struct ib_udata ucore;
 654         struct ib_uverbs_file *ufile;
 655         struct ib_ucontext *context;
 656         DECLARE_BITMAP(attr_present, UVERBS_API_ATTR_BKEY_LEN);
 657         struct uverbs_attr attrs[];
 658 };
 659
 660 static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
 661                                         unsigned int idx)
 662 {
 663         return test_bit(uapi_bkey_attr(uapi_key_attr(idx)),
 664                         attrs_bundle->attr_present);
 665 }
 666
 667 /**
 668  * rdma_udata_to_drv_context - Helper macro to get the driver's context out of
 669  *                             ib_udata which is embedded in uverbs_attr_bundle.
 670  *
 671  * If udata is not NULL this cannot fail. Otherwise a NULL udata will result
 672  * in a NULL ucontext pointer, as a safety precaution. Callers should be using
 673  * 'udata' to determine if the driver call is in user or kernel mode, not
 674  * 'ucontext'.
 675  *
 676  */
 677 #define rdma_udata_to_drv_context(udata, drv_dev_struct, member)               \
 678         (udata ? container_of(container_of(udata, struct uverbs_attr_bundle,   \
 679                                            driver_udata)                       \
 680                                       ->context,                               \
 681                               drv_dev_struct, member) :                        \
 682                  (drv_dev_struct *)NULL)
 683
 684 #define IS_UVERBS_COPY_ERR(_ret)                ((_ret) && (_ret) != -ENOENT)
 685
 686 static inline const struct uverbs_attr *uverbs_attr_get(const struct uverbs_attr_bundle *attrs_bundle,
 687                                                         u16 idx)
 688 {
 689         if (!uverbs_attr_is_valid(attrs_bundle, idx))
 690                 return ERR_PTR(-ENOENT);
 691
 692         return &attrs_bundle->attrs[uapi_bkey_attr(uapi_key_attr(idx))];
 693 }
 694
 695 static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle,
 696                                           u16 idx)
 697 {
 698         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 699
 700         if (IS_ERR(attr))
 701                 return PTR_ERR(attr);
 702
 703         return attr->ptr_attr.enum_id;
 704 }
 705
 706 static inline void *uverbs_attr_get_obj(const struct uverbs_attr_bundle *attrs_bundle,
 707                                         u16 idx)
 708 {
 709         const struct uverbs_attr *attr;
 710
 711         attr = uverbs_attr_get(attrs_bundle, idx);
 712         if (IS_ERR(attr))
 713                 return ERR_CAST(attr);
 714
 715         return attr->obj_attr.uobject->object;
 716 }
 717
 718 static inline struct ib_uobject *uverbs_attr_get_uobject(const struct uverbs_attr_bundle *attrs_bundle,
 719                                                          u16 idx)
 720 {
 721         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 722
 723         if (IS_ERR(attr))
 724                 return ERR_CAST(attr);
 725
 726         return attr->obj_attr.uobject;
 727 }
 728
 729 static inline int
 730 uverbs_attr_get_len(const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
 731 {
 732         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 733
 734         if (IS_ERR(attr))
 735                 return PTR_ERR(attr);
 736
 737         return attr->ptr_attr.len;
 738 }
 739
 740 /*
 741  * uverbs_attr_ptr_get_array_size() - Get array size pointer by a ptr
 742  * attribute.
 743  * @attrs: The attribute bundle
 744  * @idx: The ID of the attribute
 745  * @elem_size: The size of the element in the array
 746  */
 747 static inline int
 748 uverbs_attr_ptr_get_array_size(struct uverbs_attr_bundle *attrs, u16 idx,
 749                                size_t elem_size)
 750 {
 751         int size = uverbs_attr_get_len(attrs, idx);
 752
 753         if (size < 0)
 754                 return size;
 755
 756         if (size % elem_size)
 757                 return -EINVAL;
 758
 759         return size / elem_size;
 760 }
 761
 762 /**
 763  * uverbs_attr_get_uobjs_arr() - Provides array's properties for attribute for
 764  * UVERBS_ATTR_TYPE_IDRS_ARRAY.
 765  * @arr: Returned pointer to array of pointers for uobjects or NULL if
 766  *       the attribute isn't provided.
 767  *
 768  * Return: The array length or 0 if no attribute was provided.
 769  */
 770 static inline int uverbs_attr_get_uobjs_arr(
 771         const struct uverbs_attr_bundle *attrs_bundle, u16 attr_idx,
 772         struct ib_uobject ***arr)
 773 {
 774         const struct uverbs_attr *attr =
 775                         uverbs_attr_get(attrs_bundle, attr_idx);
 776
 777         if (IS_ERR(attr)) {
 778                 *arr = NULL;
 779                 return 0;
 780         }
 781
 782         *arr = attr->objs_arr_attr.uobjects;
 783
 784         return attr->objs_arr_attr.len;
 785 }
 786
 787 static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr)
 788 {
 789         return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data);
 790 }
 791
 792 static inline void *uverbs_attr_get_alloced_ptr(
 793         const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
 794 {
 795         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 796
 797         if (IS_ERR(attr))
 798                 return (void *)attr;
 799
 800         return uverbs_attr_ptr_is_inline(attr) ? (void *)&attr->ptr_attr.data :
 801                                                  attr->ptr_attr.ptr;
 802 }
 803
 804 static inline int _uverbs_copy_from(void *to,
 805                                     const struct uverbs_attr_bundle *attrs_bundle,
 806                                     size_t idx,
 807                                     size_t size)
 808 {
 809         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 810
 811         if (IS_ERR(attr))
 812                 return PTR_ERR(attr);
 813
 814         /*
 815          * Validation ensures attr->ptr_attr.len >= size. If the caller is
 816          * using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call
 817          * uverbs_copy_from_or_zero.
 818          */
 819         if (unlikely(size < attr->ptr_attr.len))
 820                 return -EINVAL;
 821
 822         if (uverbs_attr_ptr_is_inline(attr))
 823                 memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
 824         else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
 825                                 attr->ptr_attr.len))
 826                 return -EFAULT;
 827
 828         return 0;
 829 }
 830
 831 static inline int _uverbs_copy_from_or_zero(void *to,
 832                                             const struct uverbs_attr_bundle *attrs_bundle,
 833                                             size_t idx,
 834                                             size_t size)
 835 {
 836         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 837         size_t min_size;
 838
 839         if (IS_ERR(attr))
 840                 return PTR_ERR(attr);
 841
 842         min_size = min_t(size_t, size, attr->ptr_attr.len);
 843
 844         if (uverbs_attr_ptr_is_inline(attr))
 845                 memcpy(to, &attr->ptr_attr.data, min_size);
 846         else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
 847                                 min_size))
 848                 return -EFAULT;
 849
 850         if (size > min_size)
 851                 memset(to + min_size, 0, size - min_size);
 852
 853         return 0;
 854 }
 855
 856 #define uverbs_copy_from(to, attrs_bundle, idx)                               \
 857         _uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to))
 858
 859 #define uverbs_copy_from_or_zero(to, attrs_bundle, idx)                       \
 860         _uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to))
 861
 862 static inline struct ib_ucontext *
 863 ib_uverbs_get_ucontext(const struct uverbs_attr_bundle *attrs)
 864 {
 865         return ib_uverbs_get_ucontext_file(attrs->ufile);
 866 }
 867
 868 #if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
 869 int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 870                        size_t idx, u64 allowed_bits);
 871 int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
 872                        size_t idx, u64 allowed_bits);
 873 int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle, size_t idx,
 874                    const void *from, size_t size);
 875 __malloc void *_uverbs_alloc(struct uverbs_attr_bundle *bundle, size_t size,
 876                              gfp_t flags);
 877
 878 static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
 879                                           size_t size)
 880 {
 881         return _uverbs_alloc(bundle, size, GFP_KERNEL);
 882 }
 883
 884 static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
 885                                            size_t size)
 886 {
 887         return _uverbs_alloc(bundle, size, GFP_KERNEL | __GFP_ZERO);
 888 }
 889 int _uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 890                       size_t idx, s64 lower_bound, u64 upper_bound,
 891                       s64 *def_val);
 892 int uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
 893                                   size_t idx, const void *from, size_t size);
 894 #else
 895 static inline int
 896 uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 897                    size_t idx, u64 allowed_bits)
 898 {
 899         return -EINVAL;
 900 }
 901 static inline int
 902 uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
 903                    size_t idx, u64 allowed_bits)
 904 {
 905         return -EINVAL;
 906 }
 907 static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
 908                                  size_t idx, const void *from, size_t size)
 909 {
 910         return -EINVAL;
 911 }
 912 static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
 913                                           size_t size)
 914 {
 915         return ERR_PTR(-EINVAL);
 916 }
 917 static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
 918                                            size_t size)
 919 {
 920         return ERR_PTR(-EINVAL);
 921 }
 922 static inline int
 923 _uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 924                   size_t idx, s64 lower_bound, u64 upper_bound,
 925                   s64 *def_val)
 926 {
 927         return -EINVAL;
 928 }
 929 static inline int
 930 uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
 931                               size_t idx, const void *from, size_t size)
 932 {
 933         return -EINVAL;
 934 }
 935 #endif
 936
 937 #define uverbs_get_const(_to, _attrs_bundle, _idx)                             \
 938         ({                                                                     \
 939                 s64 _val;                                                      \
 940                 int _ret = _uverbs_get_const(&_val, _attrs_bundle, _idx,       \
 941                                              type_min(typeof(*_to)),           \
 942                                              type_max(typeof(*_to)), NULL);    \
 943                 (*_to) = _val;                                                 \
 944                 _ret;                                                          \
 945         })
 946
 947 #define uverbs_get_const_default(_to, _attrs_bundle, _idx, _default)           \
 948         ({                                                                     \
 949                 s64 _val;                                                      \
 950                 s64 _def_val = _default;                                       \
 951                 int _ret =                                                     \
 952                         _uverbs_get_const(&_val, _attrs_bundle, _idx,          \
 953                                           type_min(typeof(*_to)),              \
 954                                           type_max(typeof(*_to)), &_def_val);  \
 955                 (*_to) = _val;                                                 \
 956                 _ret;                                                          \
 957         })
 958 #endif