include/rdma/uverbs_ioctl.h

   1 /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
   2 /*
   3  * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
   4  */
   5
   6 #ifndef _UVERBS_IOCTL_
   7 #define _UVERBS_IOCTL_
   8
   9 #include <rdma/uverbs_types.h>
  10 #include <linux/uaccess.h>
  11 #include <rdma/rdma_user_ioctl.h>
  12 #include <rdma/ib_user_ioctl_verbs.h>
  13 #include <rdma/ib_user_ioctl_cmds.h>
  14
  15 /*
  16  * =======================================
  17  *      Verbs action specifications
  18  * =======================================
  19  */
  20
  21 enum uverbs_attr_type {
  22         UVERBS_ATTR_TYPE_NA,
  23         UVERBS_ATTR_TYPE_PTR_IN,
  24         UVERBS_ATTR_TYPE_PTR_OUT,
  25         UVERBS_ATTR_TYPE_IDR,
  26         UVERBS_ATTR_TYPE_FD,
  27         UVERBS_ATTR_TYPE_ENUM_IN,
  28         UVERBS_ATTR_TYPE_IDRS_ARRAY,
  29 };
  30
  31 enum uverbs_obj_access {
  32         UVERBS_ACCESS_READ,
  33         UVERBS_ACCESS_WRITE,
  34         UVERBS_ACCESS_NEW,
  35         UVERBS_ACCESS_DESTROY
  36 };
  37
  38 /* Specification of a single attribute inside the ioctl message */
  39 /* good size 16 */
  40 struct uverbs_attr_spec {
  41         u8 type;
  42
  43         /*
  44          * Support extending attributes by length. Allow the user to provide
  45          * more bytes than ptr.len, but check that everything after is zero'd
  46          * by the user.
  47          */
  48         u8 zero_trailing:1;
  49         /*
  50          * Valid only for PTR_IN. Allocate and copy the data inside
  51          * the parser
  52          */
  53         u8 alloc_and_copy:1;
  54         u8 mandatory:1;
  55         /* True if this is from UVERBS_ATTR_UHW */
  56         u8 is_udata:1;
  57
  58         union {
  59                 struct {
  60                         /* Current known size to kernel */
  61                         u16 len;
  62                         /* User isn't allowed to provide something < min_len */
  63                         u16 min_len;
  64                 } ptr;
  65
  66                 struct {
  67                         /*
  68                          * higher bits mean the namespace and lower bits mean
  69                          * the type id within the namespace.
  70                          */
  71                         u16 obj_type;
  72                         u8 access;
  73                 } obj;
  74
  75                 struct {
  76                         u8 num_elems;
  77                 } enum_def;
  78         } u;
  79
  80         /* This weird split lets us remove some padding */
  81         union {
  82                 struct {
  83                         /*
  84                          * The enum attribute can select one of the attributes
  85                          * contained in the ids array. Currently only PTR_IN
  86                          * attributes are supported in the ids array.
  87                          */
  88                         const struct uverbs_attr_spec *ids;
  89                 } enum_def;
  90
  91                 struct {
  92                         /*
  93                          * higher bits mean the namespace and lower bits mean
  94                          * the type id within the namespace.
  95                          */
  96                         u16                             obj_type;
  97                         u16                             min_len;
  98                         u16                             max_len;
  99                         u8                              access;
 100                 } objs_arr;
 101         } u2;
 102 };
 103
 104 /*
 105  * Information about the API is loaded into a radix tree. For IOCTL we start
 106  * with a tuple of:
 107  *  object_id, attr_id, method_id
 108  *
 109  * Which is a 48 bit value, with most of the bits guaranteed to be zero. Based
 110  * on the current kernel support this is compressed into 16 bit key for the
 111  * radix tree. Since this compression is entirely internal to the kernel the
 112  * below limits can be revised if the kernel gains additional data.
 113  *
 114  * With 64 leafs per node this is a 3 level radix tree.
 115  *
 116  * The tree encodes multiple types, and uses a scheme where OBJ_ID,0,0 returns
 117  * the object slot, and OBJ_ID,METH_ID,0 and returns the method slot.
 118  *
 119  * This also encodes the tables for the write() and write() extended commands
 120  * using the coding
 121  *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE,command #
 122  *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE_EX,command_ex #
 123  * ie the WRITE path is treated as a special method type in the ioctl
 124  * framework.
 125  */
 126 enum uapi_radix_data {
 127         UVERBS_API_NS_FLAG = 1U << UVERBS_ID_NS_SHIFT,
 128
 129         UVERBS_API_ATTR_KEY_BITS = 6,
 130         UVERBS_API_ATTR_KEY_MASK = GENMASK(UVERBS_API_ATTR_KEY_BITS - 1, 0),
 131         UVERBS_API_ATTR_BKEY_LEN = (1 << UVERBS_API_ATTR_KEY_BITS) - 1,
 132         UVERBS_API_WRITE_KEY_NUM = 1 << UVERBS_API_ATTR_KEY_BITS,
 133
 134         UVERBS_API_METHOD_KEY_BITS = 5,
 135         UVERBS_API_METHOD_KEY_SHIFT = UVERBS_API_ATTR_KEY_BITS,
 136         UVERBS_API_METHOD_KEY_NUM_CORE = 22,
 137         UVERBS_API_METHOD_IS_WRITE = 30 << UVERBS_API_METHOD_KEY_SHIFT,
 138         UVERBS_API_METHOD_IS_WRITE_EX = 31 << UVERBS_API_METHOD_KEY_SHIFT,
 139         UVERBS_API_METHOD_KEY_NUM_DRIVER =
 140                 (UVERBS_API_METHOD_IS_WRITE >> UVERBS_API_METHOD_KEY_SHIFT) -
 141                 UVERBS_API_METHOD_KEY_NUM_CORE,
 142         UVERBS_API_METHOD_KEY_MASK = GENMASK(
 143                 UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT - 1,
 144                 UVERBS_API_METHOD_KEY_SHIFT),
 145
 146         UVERBS_API_OBJ_KEY_BITS = 5,
 147         UVERBS_API_OBJ_KEY_SHIFT =
 148                 UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT,
 149         UVERBS_API_OBJ_KEY_NUM_CORE = 20,
 150         UVERBS_API_OBJ_KEY_NUM_DRIVER =
 151                 (1 << UVERBS_API_OBJ_KEY_BITS) - UVERBS_API_OBJ_KEY_NUM_CORE,
 152         UVERBS_API_OBJ_KEY_MASK = GENMASK(31, UVERBS_API_OBJ_KEY_SHIFT),
 153
 154         /* This id guaranteed to not exist in the radix tree */
 155         UVERBS_API_KEY_ERR = 0xFFFFFFFF,
 156 };
 157
 158 static inline __attribute_const__ u32 uapi_key_obj(u32 id)
 159 {
 160         if (id & UVERBS_API_NS_FLAG) {
 161                 id &= ~UVERBS_API_NS_FLAG;
 162                 if (id >= UVERBS_API_OBJ_KEY_NUM_DRIVER)
 163                         return UVERBS_API_KEY_ERR;
 164                 id = id + UVERBS_API_OBJ_KEY_NUM_CORE;
 165         } else {
 166                 if (id >= UVERBS_API_OBJ_KEY_NUM_CORE)
 167                         return UVERBS_API_KEY_ERR;
 168         }
 169
 170         return id << UVERBS_API_OBJ_KEY_SHIFT;
 171 }
 172
 173 static inline __attribute_const__ bool uapi_key_is_object(u32 key)
 174 {
 175         return (key & ~UVERBS_API_OBJ_KEY_MASK) == 0;
 176 }
 177
 178 static inline __attribute_const__ u32 uapi_key_ioctl_method(u32 id)
 179 {
 180         if (id & UVERBS_API_NS_FLAG) {
 181                 id &= ~UVERBS_API_NS_FLAG;
 182                 if (id >= UVERBS_API_METHOD_KEY_NUM_DRIVER)
 183                         return UVERBS_API_KEY_ERR;
 184                 id = id + UVERBS_API_METHOD_KEY_NUM_CORE;
 185         } else {
 186                 id++;
 187                 if (id >= UVERBS_API_METHOD_KEY_NUM_CORE)
 188                         return UVERBS_API_KEY_ERR;
 189         }
 190
 191         return id << UVERBS_API_METHOD_KEY_SHIFT;
 192 }
 193
 194 static inline __attribute_const__ u32 uapi_key_write_method(u32 id)
 195 {
 196         if (id >= UVERBS_API_WRITE_KEY_NUM)
 197                 return UVERBS_API_KEY_ERR;
 198         return UVERBS_API_METHOD_IS_WRITE | id;
 199 }
 200
 201 static inline __attribute_const__ u32 uapi_key_write_ex_method(u32 id)
 202 {
 203         if (id >= UVERBS_API_WRITE_KEY_NUM)
 204                 return UVERBS_API_KEY_ERR;
 205         return UVERBS_API_METHOD_IS_WRITE_EX | id;
 206 }
 207
 208 static inline __attribute_const__ u32
 209 uapi_key_attr_to_ioctl_method(u32 attr_key)
 210 {
 211         return attr_key &
 212                (UVERBS_API_OBJ_KEY_MASK | UVERBS_API_METHOD_KEY_MASK);
 213 }
 214
 215 static inline __attribute_const__ bool uapi_key_is_ioctl_method(u32 key)
 216 {
 217         unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;
 218
 219         return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
 220                (key & UVERBS_API_ATTR_KEY_MASK) == 0;
 221 }
 222
 223 static inline __attribute_const__ bool uapi_key_is_write_method(u32 key)
 224 {
 225         return (key & UVERBS_API_METHOD_KEY_MASK) == UVERBS_API_METHOD_IS_WRITE;
 226 }
 227
 228 static inline __attribute_const__ bool uapi_key_is_write_ex_method(u32 key)
 229 {
 230         return (key & UVERBS_API_METHOD_KEY_MASK) ==
 231                UVERBS_API_METHOD_IS_WRITE_EX;
 232 }
 233
 234 static inline __attribute_const__ u32 uapi_key_attrs_start(u32 ioctl_method_key)
 235 {
 236         /* 0 is the method slot itself */
 237         return ioctl_method_key + 1;
 238 }
 239
 240 static inline __attribute_const__ u32 uapi_key_attr(u32 id)
 241 {
 242         /*
 243          * The attr is designed to fit in the typical single radix tree node
 244          * of 64 entries. Since allmost all methods have driver attributes we
 245          * organize things so that the driver and core attributes interleave to
 246          * reduce the length of the attributes array in typical cases.
 247          */
 248         if (id & UVERBS_API_NS_FLAG) {
 249                 id &= ~UVERBS_API_NS_FLAG;
 250                 id++;
 251                 if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
 252                         return UVERBS_API_KEY_ERR;
 253                 id = (id << 1) | 0;
 254         } else {
 255                 if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
 256                         return UVERBS_API_KEY_ERR;
 257                 id = (id << 1) | 1;
 258         }
 259
 260         return id;
 261 }
 262
 263 /* Only true for ioctl methods */
 264 static inline __attribute_const__ bool uapi_key_is_attr(u32 key)
 265 {
 266         unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;
 267
 268         return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
 269                (key & UVERBS_API_ATTR_KEY_MASK) != 0;
 270 }
 271
 272 /*
 273  * This returns a value in the range [0 to UVERBS_API_ATTR_BKEY_LEN),
 274  * basically it undoes the reservation of 0 in the ID numbering. attr_key
 275  * must already be masked with UVERBS_API_ATTR_KEY_MASK, or be the output of
 276  * uapi_key_attr().
 277  */
 278 static inline __attribute_const__ u32 uapi_bkey_attr(u32 attr_key)
 279 {
 280         return attr_key - 1;
 281 }
 282
 283 static inline __attribute_const__ u32 uapi_bkey_to_key_attr(u32 attr_bkey)
 284 {
 285         return attr_bkey + 1;
 286 }
 287
 288 /*
 289  * =======================================
 290  *      Verbs definitions
 291  * =======================================
 292  */
 293
 294 struct uverbs_attr_def {
 295         u16                           id;
 296         struct uverbs_attr_spec       attr;
 297 };
 298
 299 struct uverbs_method_def {
 300         u16                                  id;
 301         /* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
 302         u32                                  flags;
 303         size_t                               num_attrs;
 304         const struct uverbs_attr_def * const (*attrs)[];
 305         int (*handler)(struct uverbs_attr_bundle *attrs);
 306 };
 307
 308 struct uverbs_object_def {
 309         u16                                      id;
 310         const struct uverbs_obj_type            *type_attrs;
 311         size_t                                   num_methods;
 312         const struct uverbs_method_def * const (*methods)[];
 313 };
 314
 315 enum uapi_definition_kind {
 316         UAPI_DEF_END = 0,
 317         UAPI_DEF_OBJECT_START,
 318         UAPI_DEF_WRITE,
 319         UAPI_DEF_CHAIN_OBJ_TREE,
 320         UAPI_DEF_CHAIN,
 321         UAPI_DEF_IS_SUPPORTED_FUNC,
 322         UAPI_DEF_IS_SUPPORTED_DEV_FN,
 323 };
 324
 325 enum uapi_definition_scope {
 326         UAPI_SCOPE_OBJECT = 1,
 327         UAPI_SCOPE_METHOD = 2,
 328 };
 329
 330 struct uapi_definition {
 331         u8 kind;
 332         u8 scope;
 333         union {
 334                 struct {
 335                         u16 object_id;
 336                 } object_start;
 337                 struct {
 338                         u16 command_num;
 339                         u8 is_ex:1;
 340                         u8 has_udata:1;
 341                         u8 has_resp:1;
 342                         u8 req_size;
 343                         u8 resp_size;
 344                 } write;
 345         };
 346
 347         union {
 348                 bool (*func_is_supported)(struct ib_device *device);
 349                 int (*func_write)(struct uverbs_attr_bundle *attrs);
 350                 const struct uapi_definition *chain;
 351                 const struct uverbs_object_def *chain_obj_tree;
 352                 size_t needs_fn_offset;
 353         };
 354 };
 355
 356 /* Define things connected to object_id */
 357 #define DECLARE_UVERBS_OBJECT(_object_id, ...)                                 \
 358         {                                                                      \
 359                 .kind = UAPI_DEF_OBJECT_START,                                 \
 360                 .object_start = { .object_id = _object_id },                   \
 361         },                                                                     \
 362                 ##__VA_ARGS__
 363
 364 /* Use in a var_args of DECLARE_UVERBS_OBJECT */
 365 #define DECLARE_UVERBS_WRITE(_command_num, _func, _cmd_desc, ...)              \
 366         {                                                                      \
 367                 .kind = UAPI_DEF_WRITE,                                        \
 368                 .scope = UAPI_SCOPE_OBJECT,                                    \
 369                 .write = { .is_ex = 0, .command_num = _command_num },          \
 370                 .func_write = _func,                                           \
 371                 _cmd_desc,                                                     \
 372         },                                                                     \
 373                 ##__VA_ARGS__
 374
 375 /* Use in a var_args of DECLARE_UVERBS_OBJECT */
 376 #define DECLARE_UVERBS_WRITE_EX(_command_num, _func, _cmd_desc, ...)           \
 377         {                                                                      \
 378                 .kind = UAPI_DEF_WRITE,                                        \
 379                 .scope = UAPI_SCOPE_OBJECT,                                    \
 380                 .write = { .is_ex = 1, .command_num = _command_num },          \
 381                 .func_write = _func,                                           \
 382                 _cmd_desc,                                                     \
 383         },                                                                     \
 384                 ##__VA_ARGS__
 385
 386 /*
 387  * Object is only supported if the function pointer named ibdev_fn in struct
 388  * ib_device is not NULL.
 389  */
 390 #define UAPI_DEF_OBJ_NEEDS_FN(ibdev_fn)                                        \
 391         {                                                                      \
 392                 .kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
 393                 .scope = UAPI_SCOPE_OBJECT,                                    \
 394                 .needs_fn_offset =                                             \
 395                         offsetof(struct ib_device_ops, ibdev_fn) +             \
 396                         BUILD_BUG_ON_ZERO(sizeof_field(struct ib_device_ops,   \
 397                                                        ibdev_fn) !=            \
 398                                           sizeof(void *)),                     \
 399         }
 400
 401 /*
 402  * Method is only supported if the function pointer named ibdev_fn in struct
 403  * ib_device is not NULL.
 404  */
 405 #define UAPI_DEF_METHOD_NEEDS_FN(ibdev_fn)                                     \
 406         {                                                                      \
 407                 .kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
 408                 .scope = UAPI_SCOPE_METHOD,                                    \
 409                 .needs_fn_offset =                                             \
 410                         offsetof(struct ib_device_ops, ibdev_fn) +             \
 411                         BUILD_BUG_ON_ZERO(sizeof_field(struct ib_device_ops,   \
 412                                                        ibdev_fn) !=            \
 413                                           sizeof(void *)),                     \
 414         }
 415
 416 /* Call a function to determine if the entire object is supported or not */
 417 #define UAPI_DEF_IS_OBJ_SUPPORTED(_func)                                       \
 418         {                                                                      \
 419                 .kind = UAPI_DEF_IS_SUPPORTED_FUNC,                            \
 420                 .scope = UAPI_SCOPE_OBJECT, .func_is_supported = _func,        \
 421         }
 422
 423 /* Include another struct uapi_definition in this one */
 424 #define UAPI_DEF_CHAIN(_def_var)                                               \
 425         {                                                                      \
 426                 .kind = UAPI_DEF_CHAIN, .chain = _def_var,                     \
 427         }
 428
 429 /* Temporary until the tree base description is replaced */
 430 #define UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, _object_ptr, ...)                \
 431         {                                                                      \
 432                 .kind = UAPI_DEF_CHAIN_OBJ_TREE,                               \
 433                 .object_start = { .object_id = _object_enum },                 \
 434                 .chain_obj_tree = _object_ptr,                                 \
 435         },                                                                     \
 436                 ##__VA_ARGS__
 437 #define UAPI_DEF_CHAIN_OBJ_TREE_NAMED(_object_enum, ...)                       \
 438         UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, &UVERBS_OBJECT(_object_enum),    \
 439                                 ##__VA_ARGS__)
 440
 441 /*
 442  * =======================================
 443  *      Attribute Specifications
 444  * =======================================
 445  */
 446
 447 #define UVERBS_ATTR_SIZE(_min_len, _len)                        \
 448         .u.ptr.min_len = _min_len, .u.ptr.len = _len
 449
 450 #define UVERBS_ATTR_NO_DATA() UVERBS_ATTR_SIZE(0, 0)
 451
 452 /*
 453  * Specifies a uapi structure that cannot be extended. The user must always
 454  * supply the whole structure and nothing more. The structure must be declared
 455  * in a header under include/uapi/rdma.
 456  */
 457 #define UVERBS_ATTR_TYPE(_type)                                 \
 458         .u.ptr.min_len = sizeof(_type), .u.ptr.len = sizeof(_type)
 459 /*
 460  * Specifies a uapi structure where the user must provide at least up to
 461  * member 'last'.  Anything after last and up until the end of the structure
 462  * can be non-zero, anything longer than the end of the structure must be
 463  * zero. The structure must be declared in a header under include/uapi/rdma.
 464  */
 465 #define UVERBS_ATTR_STRUCT(_type, _last)                                       \
 466         .zero_trailing = 1,                                                    \
 467         UVERBS_ATTR_SIZE(offsetofend(_type, _last), sizeof(_type))
 468 /*
 469  * Specifies at least min_len bytes must be passed in, but the amount can be
 470  * larger, up to the protocol maximum size. No check for zeroing is done.
 471  */
 472 #define UVERBS_ATTR_MIN_SIZE(_min_len) UVERBS_ATTR_SIZE(_min_len, USHRT_MAX)
 473
 474 /* Must be used in the '...' of any UVERBS_ATTR */
 475 #define UA_ALLOC_AND_COPY .alloc_and_copy = 1
 476 #define UA_MANDATORY .mandatory = 1
 477 #define UA_OPTIONAL .mandatory = 0
 478
 479 /*
 480  * min_len must be bigger than 0 and _max_len must be smaller than 4095.  Only
 481  * READ\WRITE accesses are supported.
 482  */
 483 #define UVERBS_ATTR_IDRS_ARR(_attr_id, _idr_type, _access, _min_len, _max_len, \
 484                              ...)                                              \
 485         (&(const struct uverbs_attr_def){                                      \
 486                 .id = (_attr_id) +                                             \
 487                       BUILD_BUG_ON_ZERO((_min_len) == 0 ||                     \
 488                                         (_max_len) >                           \
 489                                                 PAGE_SIZE / sizeof(void *) ||  \
 490                                         (_min_len) > (_max_len) ||             \
 491                                         (_access) == UVERBS_ACCESS_NEW ||      \
 492                                         (_access) == UVERBS_ACCESS_DESTROY),   \
 493                 .attr = { .type = UVERBS_ATTR_TYPE_IDRS_ARRAY,                 \
 494                           .u2.objs_arr.obj_type = _idr_type,                   \
 495                           .u2.objs_arr.access = _access,                       \
 496                           .u2.objs_arr.min_len = _min_len,                     \
 497                           .u2.objs_arr.max_len = _max_len,                     \
 498                           __VA_ARGS__ } })
 499
 500 /*
 501  * Only for use with UVERBS_ATTR_IDR, allows any uobject type to be accepted,
 502  * the user must validate the type of the uobject instead.
 503  */
 504 #define UVERBS_IDR_ANY_OBJECT 0xFFFF
 505
 506 #define UVERBS_ATTR_IDR(_attr_id, _idr_type, _access, ...)                     \
 507         (&(const struct uverbs_attr_def){                                      \
 508                 .id = _attr_id,                                                \
 509                 .attr = { .type = UVERBS_ATTR_TYPE_IDR,                        \
 510                           .u.obj.obj_type = _idr_type,                         \
 511                           .u.obj.access = _access,                             \
 512                           __VA_ARGS__ } })
 513
 514 #define UVERBS_ATTR_FD(_attr_id, _fd_type, _access, ...)                       \
 515         (&(const struct uverbs_attr_def){                                      \
 516                 .id = (_attr_id) +                                             \
 517                       BUILD_BUG_ON_ZERO((_access) != UVERBS_ACCESS_NEW &&      \
 518                                         (_access) != UVERBS_ACCESS_READ),      \
 519                 .attr = { .type = UVERBS_ATTR_TYPE_FD,                         \
 520                           .u.obj.obj_type = _fd_type,                          \
 521                           .u.obj.access = _access,                             \
 522                           __VA_ARGS__ } })
 523
 524 #define UVERBS_ATTR_PTR_IN(_attr_id, _type, ...)                               \
 525         (&(const struct uverbs_attr_def){                                      \
 526                 .id = _attr_id,                                                \
 527                 .attr = { .type = UVERBS_ATTR_TYPE_PTR_IN,                     \
 528                           _type,                                               \
 529                           __VA_ARGS__ } })
 530
 531 #define UVERBS_ATTR_PTR_OUT(_attr_id, _type, ...)                              \
 532         (&(const struct uverbs_attr_def){                                      \
 533                 .id = _attr_id,                                                \
 534                 .attr = { .type = UVERBS_ATTR_TYPE_PTR_OUT,                    \
 535                           _type,                                               \
 536                           __VA_ARGS__ } })
 537
 538 /* _enum_arry should be a 'static const union uverbs_attr_spec[]' */
 539 #define UVERBS_ATTR_ENUM_IN(_attr_id, _enum_arr, ...)                          \
 540         (&(const struct uverbs_attr_def){                                      \
 541                 .id = _attr_id,                                                \
 542                 .attr = { .type = UVERBS_ATTR_TYPE_ENUM_IN,                    \
 543                           .u2.enum_def.ids = _enum_arr,                        \
 544                           .u.enum_def.num_elems = ARRAY_SIZE(_enum_arr),       \
 545                           __VA_ARGS__ },                                       \
 546         })
 547
 548 /* An input value that is a member in the enum _enum_type. */
 549 #define UVERBS_ATTR_CONST_IN(_attr_id, _enum_type, ...)                        \
 550         UVERBS_ATTR_PTR_IN(                                                    \
 551                 _attr_id,                                                      \
 552                 UVERBS_ATTR_SIZE(                                              \
 553                         sizeof(u64) + BUILD_BUG_ON_ZERO(!sizeof(_enum_type)),  \
 554                         sizeof(u64)),                                          \
 555                 __VA_ARGS__)
 556
 557 /*
 558  * An input value that is a bitwise combination of values of _enum_type.
 559  * This permits the flag value to be passed as either a u32 or u64, it must
 560  * be retrieved via uverbs_get_flag().
 561  */
 562 #define UVERBS_ATTR_FLAGS_IN(_attr_id, _enum_type, ...)                        \
 563         UVERBS_ATTR_PTR_IN(                                                    \
 564                 _attr_id,                                                      \
 565                 UVERBS_ATTR_SIZE(sizeof(u32) + BUILD_BUG_ON_ZERO(              \
 566                                                        !sizeof(_enum_type *)), \
 567                                  sizeof(u64)),                                 \
 568                 __VA_ARGS__)
 569
 570 /*
 571  * This spec is used in order to pass information to the hardware driver in a
 572  * legacy way. Every verb that could get driver specific data should get this
 573  * spec.
 574  */
 575 #define UVERBS_ATTR_UHW()                                                      \
 576         UVERBS_ATTR_PTR_IN(UVERBS_ATTR_UHW_IN,                                 \
 577                            UVERBS_ATTR_MIN_SIZE(0),                            \
 578                            UA_OPTIONAL,                                        \
 579                            .is_udata = 1),                                     \
 580         UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT,                               \
 581                             UVERBS_ATTR_MIN_SIZE(0),                           \
 582                             UA_OPTIONAL,                                       \
 583                             .is_udata = 1)
 584
 585 /* =================================================
 586  *              Parsing infrastructure
 587  * =================================================
 588  */
 589
 590
 591 struct uverbs_ptr_attr {
 592         /*
 593          * If UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY is set then the 'ptr' is
 594          * used.
 595          */
 596         union {
 597                 void *ptr;
 598                 u64 data;
 599         };
 600         u16             len;
 601         u16             uattr_idx;
 602         u8              enum_id;
 603 };
 604
 605 struct uverbs_obj_attr {
 606         struct ib_uobject               *uobject;
 607         const struct uverbs_api_attr    *attr_elm;
 608 };
 609
 610 struct uverbs_objs_arr_attr {
 611         struct ib_uobject **uobjects;
 612         u16 len;
 613 };
 614
 615 struct uverbs_attr {
 616         union {
 617                 struct uverbs_ptr_attr  ptr_attr;
 618                 struct uverbs_obj_attr  obj_attr;
 619                 struct uverbs_objs_arr_attr objs_arr_attr;
 620         };
 621 };
 622
 623 struct uverbs_attr_bundle {
 624         struct ib_udata driver_udata;
 625         struct ib_udata ucore;
 626         struct ib_uverbs_file *ufile;
 627         struct ib_ucontext *context;
 628         struct ib_uobject *uobject;
 629         DECLARE_BITMAP(attr_present, UVERBS_API_ATTR_BKEY_LEN);
 630         struct uverbs_attr attrs[];
 631 };
 632
 633 static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
 634                                         unsigned int idx)
 635 {
 636         return test_bit(uapi_bkey_attr(uapi_key_attr(idx)),
 637                         attrs_bundle->attr_present);
 638 }
 639
 640 /**
 641  * rdma_udata_to_drv_context - Helper macro to get the driver's context out of
 642  *                             ib_udata which is embedded in uverbs_attr_bundle.
 643  *
 644  * If udata is not NULL this cannot fail. Otherwise a NULL udata will result
 645  * in a NULL ucontext pointer, as a safety precaution. Callers should be using
 646  * 'udata' to determine if the driver call is in user or kernel mode, not
 647  * 'ucontext'.
 648  *
 649  */
 650 static inline struct uverbs_attr_bundle *
 651 rdma_udata_to_uverbs_attr_bundle(struct ib_udata *udata)
 652 {
 653         return container_of(udata, struct uverbs_attr_bundle, driver_udata);
 654 }
 655
 656 #define rdma_udata_to_drv_context(udata, drv_dev_struct, member)                \
 657         (udata ? container_of(rdma_udata_to_uverbs_attr_bundle(udata)->context, \
 658                               drv_dev_struct, member) : (drv_dev_struct *)NULL)
 659
 660 #define IS_UVERBS_COPY_ERR(_ret)                ((_ret) && (_ret) != -ENOENT)
 661
 662 static inline const struct uverbs_attr *uverbs_attr_get(const struct uverbs_attr_bundle *attrs_bundle,
 663                                                         u16 idx)
 664 {
 665         if (!uverbs_attr_is_valid(attrs_bundle, idx))
 666                 return ERR_PTR(-ENOENT);
 667
 668         return &attrs_bundle->attrs[uapi_bkey_attr(uapi_key_attr(idx))];
 669 }
 670
 671 static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle,
 672                                           u16 idx)
 673 {
 674         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 675
 676         if (IS_ERR(attr))
 677                 return PTR_ERR(attr);
 678
 679         return attr->ptr_attr.enum_id;
 680 }
 681
 682 static inline void *uverbs_attr_get_obj(const struct uverbs_attr_bundle *attrs_bundle,
 683                                         u16 idx)
 684 {
 685         const struct uverbs_attr *attr;
 686
 687         attr = uverbs_attr_get(attrs_bundle, idx);
 688         if (IS_ERR(attr))
 689                 return ERR_CAST(attr);
 690
 691         return attr->obj_attr.uobject->object;
 692 }
 693
 694 static inline struct ib_uobject *uverbs_attr_get_uobject(const struct uverbs_attr_bundle *attrs_bundle,
 695                                                          u16 idx)
 696 {
 697         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 698
 699         if (IS_ERR(attr))
 700                 return ERR_CAST(attr);
 701
 702         return attr->obj_attr.uobject;
 703 }
 704
 705 static inline int
 706 uverbs_attr_get_len(const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
 707 {
 708         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 709
 710         if (IS_ERR(attr))
 711                 return PTR_ERR(attr);
 712
 713         return attr->ptr_attr.len;
 714 }
 715
 716 void uverbs_finalize_uobj_create(const struct uverbs_attr_bundle *attrs_bundle,
 717                                  u16 idx);
 718
 719 /*
 720  * uverbs_attr_ptr_get_array_size() - Get array size pointer by a ptr
 721  * attribute.
 722  * @attrs: The attribute bundle
 723  * @idx: The ID of the attribute
 724  * @elem_size: The size of the element in the array
 725  */
 726 static inline int
 727 uverbs_attr_ptr_get_array_size(struct uverbs_attr_bundle *attrs, u16 idx,
 728                                size_t elem_size)
 729 {
 730         int size = uverbs_attr_get_len(attrs, idx);
 731
 732         if (size < 0)
 733                 return size;
 734
 735         if (size % elem_size)
 736                 return -EINVAL;
 737
 738         return size / elem_size;
 739 }
 740
 741 /**
 742  * uverbs_attr_get_uobjs_arr() - Provides array's properties for attribute for
 743  * UVERBS_ATTR_TYPE_IDRS_ARRAY.
 744  * @arr: Returned pointer to array of pointers for uobjects or NULL if
 745  *       the attribute isn't provided.
 746  *
 747  * Return: The array length or 0 if no attribute was provided.
 748  */
 749 static inline int uverbs_attr_get_uobjs_arr(
 750         const struct uverbs_attr_bundle *attrs_bundle, u16 attr_idx,
 751         struct ib_uobject ***arr)
 752 {
 753         const struct uverbs_attr *attr =
 754                         uverbs_attr_get(attrs_bundle, attr_idx);
 755
 756         if (IS_ERR(attr)) {
 757                 *arr = NULL;
 758                 return 0;
 759         }
 760
 761         *arr = attr->objs_arr_attr.uobjects;
 762
 763         return attr->objs_arr_attr.len;
 764 }
 765
 766 static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr)
 767 {
 768         return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data);
 769 }
 770
 771 static inline void *uverbs_attr_get_alloced_ptr(
 772         const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
 773 {
 774         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 775
 776         if (IS_ERR(attr))
 777                 return (void *)attr;
 778
 779         return uverbs_attr_ptr_is_inline(attr) ? (void *)&attr->ptr_attr.data :
 780                                                  attr->ptr_attr.ptr;
 781 }
 782
 783 static inline int _uverbs_copy_from(void *to,
 784                                     const struct uverbs_attr_bundle *attrs_bundle,
 785                                     size_t idx,
 786                                     size_t size)
 787 {
 788         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 789
 790         if (IS_ERR(attr))
 791                 return PTR_ERR(attr);
 792
 793         /*
 794          * Validation ensures attr->ptr_attr.len >= size. If the caller is
 795          * using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call
 796          * uverbs_copy_from_or_zero.
 797          */
 798         if (unlikely(size < attr->ptr_attr.len))
 799                 return -EINVAL;
 800
 801         if (uverbs_attr_ptr_is_inline(attr))
 802                 memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
 803         else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
 804                                 attr->ptr_attr.len))
 805                 return -EFAULT;
 806
 807         return 0;
 808 }
 809
 810 static inline int _uverbs_copy_from_or_zero(void *to,
 811                                             const struct uverbs_attr_bundle *attrs_bundle,
 812                                             size_t idx,
 813                                             size_t size)
 814 {
 815         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 816         size_t min_size;
 817
 818         if (IS_ERR(attr))
 819                 return PTR_ERR(attr);
 820
 821         min_size = min_t(size_t, size, attr->ptr_attr.len);
 822
 823         if (uverbs_attr_ptr_is_inline(attr))
 824                 memcpy(to, &attr->ptr_attr.data, min_size);
 825         else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
 826                                 min_size))
 827                 return -EFAULT;
 828
 829         if (size > min_size)
 830                 memset(to + min_size, 0, size - min_size);
 831
 832         return 0;
 833 }
 834
 835 #define uverbs_copy_from(to, attrs_bundle, idx)                               \
 836         _uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to))
 837
 838 #define uverbs_copy_from_or_zero(to, attrs_bundle, idx)                       \
 839         _uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to))
 840
 841 static inline struct ib_ucontext *
 842 ib_uverbs_get_ucontext(const struct uverbs_attr_bundle *attrs)
 843 {
 844         return ib_uverbs_get_ucontext_file(attrs->ufile);
 845 }
 846
 847 #if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
 848 int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 849                        size_t idx, u64 allowed_bits);
 850 int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
 851                        size_t idx, u64 allowed_bits);
 852 int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle, size_t idx,
 853                    const void *from, size_t size);
 854 __malloc void *_uverbs_alloc(struct uverbs_attr_bundle *bundle, size_t size,
 855                              gfp_t flags);
 856
 857 static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
 858                                           size_t size)
 859 {
 860         return _uverbs_alloc(bundle, size, GFP_KERNEL);
 861 }
 862
 863 static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
 864                                            size_t size)
 865 {
 866         return _uverbs_alloc(bundle, size, GFP_KERNEL | __GFP_ZERO);
 867 }
 868
 869 static inline __malloc void *uverbs_kcalloc(struct uverbs_attr_bundle *bundle,
 870                                             size_t n, size_t size)
 871 {
 872         size_t bytes;
 873
 874         if (unlikely(check_mul_overflow(n, size, &bytes)))
 875                 return ERR_PTR(-EOVERFLOW);
 876         return uverbs_zalloc(bundle, bytes);
 877 }
 878 int _uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 879                       size_t idx, s64 lower_bound, u64 upper_bound,
 880                       s64 *def_val);
 881 int uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
 882                                   size_t idx, const void *from, size_t size);
 883 #else
 884 static inline int
 885 uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 886                    size_t idx, u64 allowed_bits)
 887 {
 888         return -EINVAL;
 889 }
 890 static inline int
 891 uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
 892                    size_t idx, u64 allowed_bits)
 893 {
 894         return -EINVAL;
 895 }
 896 static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
 897                                  size_t idx, const void *from, size_t size)
 898 {
 899         return -EINVAL;
 900 }
 901 static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
 902                                           size_t size)
 903 {
 904         return ERR_PTR(-EINVAL);
 905 }
 906 static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
 907                                            size_t size)
 908 {
 909         return ERR_PTR(-EINVAL);
 910 }
 911 static inline int
 912 _uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 913                   size_t idx, s64 lower_bound, u64 upper_bound,
 914                   s64 *def_val)
 915 {
 916         return -EINVAL;
 917 }
 918 static inline int
 919 uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
 920                               size_t idx, const void *from, size_t size)
 921 {
 922         return -EINVAL;
 923 }
 924 #endif
 925
 926 #define uverbs_get_const(_to, _attrs_bundle, _idx)                             \
 927         ({                                                                     \
 928                 s64 _val;                                                      \
 929                 int _ret = _uverbs_get_const(&_val, _attrs_bundle, _idx,       \
 930                                              type_min(typeof(*_to)),           \
 931                                              type_max(typeof(*_to)), NULL);    \
 932                 (*_to) = _val;                                                 \
 933                 _ret;                                                          \
 934         })
 935
 936 #define uverbs_get_const_default(_to, _attrs_bundle, _idx, _default)           \
 937         ({                                                                     \
 938                 s64 _val;                                                      \
 939                 s64 _def_val = _default;                                       \
 940                 int _ret =                                                     \
 941                         _uverbs_get_const(&_val, _attrs_bundle, _idx,          \
 942                                           type_min(typeof(*_to)),              \
 943                                           type_max(typeof(*_to)), &_def_val);  \
 944                 (*_to) = _val;                                                 \
 945                 _ret;                                                          \
 946         })
 947 #endif