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_RAW_FD,
  28         UVERBS_ATTR_TYPE_ENUM_IN,
  29         UVERBS_ATTR_TYPE_IDRS_ARRAY,
  30 };
  31
  32 enum uverbs_obj_access {
  33         UVERBS_ACCESS_READ,
  34         UVERBS_ACCESS_WRITE,
  35         UVERBS_ACCESS_NEW,
  36         UVERBS_ACCESS_DESTROY
  37 };
  38
  39 /* Specification of a single attribute inside the ioctl message */
  40 /* good size 16 */
  41 struct uverbs_attr_spec {
  42         u8 type;
  43
  44         /*
  45          * Support extending attributes by length. Allow the user to provide
  46          * more bytes than ptr.len, but check that everything after is zero'd
  47          * by the user.
  48          */
  49         u8 zero_trailing:1;
  50         /*
  51          * Valid only for PTR_IN. Allocate and copy the data inside
  52          * the parser
  53          */
  54         u8 alloc_and_copy:1;
  55         u8 mandatory:1;
  56         /* True if this is from UVERBS_ATTR_UHW */
  57         u8 is_udata:1;
  58
  59         union {
  60                 struct {
  61                         /* Current known size to kernel */
  62                         u16 len;
  63                         /* User isn't allowed to provide something < min_len */
  64                         u16 min_len;
  65                 } ptr;
  66
  67                 struct {
  68                         /*
  69                          * higher bits mean the namespace and lower bits mean
  70                          * the type id within the namespace.
  71                          */
  72                         u16 obj_type;
  73                         u8 access;
  74                 } obj;
  75
  76                 struct {
  77                         u8 num_elems;
  78                 } enum_def;
  79         } u;
  80
  81         /* This weird split lets us remove some padding */
  82         union {
  83                 struct {
  84                         /*
  85                          * The enum attribute can select one of the attributes
  86                          * contained in the ids array. Currently only PTR_IN
  87                          * attributes are supported in the ids array.
  88                          */
  89                         const struct uverbs_attr_spec *ids;
  90                 } enum_def;
  91
  92                 struct {
  93                         /*
  94                          * higher bits mean the namespace and lower bits mean
  95                          * the type id within the namespace.
  96                          */
  97                         u16                             obj_type;
  98                         u16                             min_len;
  99                         u16                             max_len;
 100                         u8                              access;
 101                 } objs_arr;
 102         } u2;
 103 };
 104
 105 /*
 106  * Information about the API is loaded into a radix tree. For IOCTL we start
 107  * with a tuple of:
 108  *  object_id, attr_id, method_id
 109  *
 110  * Which is a 48 bit value, with most of the bits guaranteed to be zero. Based
 111  * on the current kernel support this is compressed into 16 bit key for the
 112  * radix tree. Since this compression is entirely internal to the kernel the
 113  * below limits can be revised if the kernel gains additional data.
 114  *
 115  * With 64 leafs per node this is a 3 level radix tree.
 116  *
 117  * The tree encodes multiple types, and uses a scheme where OBJ_ID,0,0 returns
 118  * the object slot, and OBJ_ID,METH_ID,0 and returns the method slot.
 119  *
 120  * This also encodes the tables for the write() and write() extended commands
 121  * using the coding
 122  *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE,command #
 123  *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE_EX,command_ex #
 124  * ie the WRITE path is treated as a special method type in the ioctl
 125  * framework.
 126  */
 127 enum uapi_radix_data {
 128         UVERBS_API_NS_FLAG = 1U << UVERBS_ID_NS_SHIFT,
 129
 130         UVERBS_API_ATTR_KEY_BITS = 6,
 131         UVERBS_API_ATTR_KEY_MASK = GENMASK(UVERBS_API_ATTR_KEY_BITS - 1, 0),
 132         UVERBS_API_ATTR_BKEY_LEN = (1 << UVERBS_API_ATTR_KEY_BITS) - 1,
 133         UVERBS_API_WRITE_KEY_NUM = 1 << UVERBS_API_ATTR_KEY_BITS,
 134
 135         UVERBS_API_METHOD_KEY_BITS = 5,
 136         UVERBS_API_METHOD_KEY_SHIFT = UVERBS_API_ATTR_KEY_BITS,
 137         UVERBS_API_METHOD_KEY_NUM_CORE = 22,
 138         UVERBS_API_METHOD_IS_WRITE = 30 << UVERBS_API_METHOD_KEY_SHIFT,
 139         UVERBS_API_METHOD_IS_WRITE_EX = 31 << UVERBS_API_METHOD_KEY_SHIFT,
 140         UVERBS_API_METHOD_KEY_NUM_DRIVER =
 141                 (UVERBS_API_METHOD_IS_WRITE >> UVERBS_API_METHOD_KEY_SHIFT) -
 142                 UVERBS_API_METHOD_KEY_NUM_CORE,
 143         UVERBS_API_METHOD_KEY_MASK = GENMASK(
 144                 UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT - 1,
 145                 UVERBS_API_METHOD_KEY_SHIFT),
 146
 147         UVERBS_API_OBJ_KEY_BITS = 5,
 148         UVERBS_API_OBJ_KEY_SHIFT =
 149                 UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT,
 150         UVERBS_API_OBJ_KEY_NUM_CORE = 20,
 151         UVERBS_API_OBJ_KEY_NUM_DRIVER =
 152                 (1 << UVERBS_API_OBJ_KEY_BITS) - UVERBS_API_OBJ_KEY_NUM_CORE,
 153         UVERBS_API_OBJ_KEY_MASK = GENMASK(31, UVERBS_API_OBJ_KEY_SHIFT),
 154
 155         /* This id guaranteed to not exist in the radix tree */
 156         UVERBS_API_KEY_ERR = 0xFFFFFFFF,
 157 };
 158
 159 static inline __attribute_const__ u32 uapi_key_obj(u32 id)
 160 {
 161         if (id & UVERBS_API_NS_FLAG) {
 162                 id &= ~UVERBS_API_NS_FLAG;
 163                 if (id >= UVERBS_API_OBJ_KEY_NUM_DRIVER)
 164                         return UVERBS_API_KEY_ERR;
 165                 id = id + UVERBS_API_OBJ_KEY_NUM_CORE;
 166         } else {
 167                 if (id >= UVERBS_API_OBJ_KEY_NUM_CORE)
 168                         return UVERBS_API_KEY_ERR;
 169         }
 170
 171         return id << UVERBS_API_OBJ_KEY_SHIFT;
 172 }
 173
 174 static inline __attribute_const__ bool uapi_key_is_object(u32 key)
 175 {
 176         return (key & ~UVERBS_API_OBJ_KEY_MASK) == 0;
 177 }
 178
 179 static inline __attribute_const__ u32 uapi_key_ioctl_method(u32 id)
 180 {
 181         if (id & UVERBS_API_NS_FLAG) {
 182                 id &= ~UVERBS_API_NS_FLAG;
 183                 if (id >= UVERBS_API_METHOD_KEY_NUM_DRIVER)
 184                         return UVERBS_API_KEY_ERR;
 185                 id = id + UVERBS_API_METHOD_KEY_NUM_CORE;
 186         } else {
 187                 id++;
 188                 if (id >= UVERBS_API_METHOD_KEY_NUM_CORE)
 189                         return UVERBS_API_KEY_ERR;
 190         }
 191
 192         return id << UVERBS_API_METHOD_KEY_SHIFT;
 193 }
 194
 195 static inline __attribute_const__ u32 uapi_key_write_method(u32 id)
 196 {
 197         if (id >= UVERBS_API_WRITE_KEY_NUM)
 198                 return UVERBS_API_KEY_ERR;
 199         return UVERBS_API_METHOD_IS_WRITE | id;
 200 }
 201
 202 static inline __attribute_const__ u32 uapi_key_write_ex_method(u32 id)
 203 {
 204         if (id >= UVERBS_API_WRITE_KEY_NUM)
 205                 return UVERBS_API_KEY_ERR;
 206         return UVERBS_API_METHOD_IS_WRITE_EX | id;
 207 }
 208
 209 static inline __attribute_const__ u32
 210 uapi_key_attr_to_ioctl_method(u32 attr_key)
 211 {
 212         return attr_key &
 213                (UVERBS_API_OBJ_KEY_MASK | UVERBS_API_METHOD_KEY_MASK);
 214 }
 215
 216 static inline __attribute_const__ bool uapi_key_is_ioctl_method(u32 key)
 217 {
 218         unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;
 219
 220         return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
 221                (key & UVERBS_API_ATTR_KEY_MASK) == 0;
 222 }
 223
 224 static inline __attribute_const__ bool uapi_key_is_write_method(u32 key)
 225 {
 226         return (key & UVERBS_API_METHOD_KEY_MASK) == UVERBS_API_METHOD_IS_WRITE;
 227 }
 228
 229 static inline __attribute_const__ bool uapi_key_is_write_ex_method(u32 key)
 230 {
 231         return (key & UVERBS_API_METHOD_KEY_MASK) ==
 232                UVERBS_API_METHOD_IS_WRITE_EX;
 233 }
 234
 235 static inline __attribute_const__ u32 uapi_key_attrs_start(u32 ioctl_method_key)
 236 {
 237         /* 0 is the method slot itself */
 238         return ioctl_method_key + 1;
 239 }
 240
 241 static inline __attribute_const__ u32 uapi_key_attr(u32 id)
 242 {
 243         /*
 244          * The attr is designed to fit in the typical single radix tree node
 245          * of 64 entries. Since allmost all methods have driver attributes we
 246          * organize things so that the driver and core attributes interleave to
 247          * reduce the length of the attributes array in typical cases.
 248          */
 249         if (id & UVERBS_API_NS_FLAG) {
 250                 id &= ~UVERBS_API_NS_FLAG;
 251                 id++;
 252                 if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
 253                         return UVERBS_API_KEY_ERR;
 254                 id = (id << 1) | 0;
 255         } else {
 256                 if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
 257                         return UVERBS_API_KEY_ERR;
 258                 id = (id << 1) | 1;
 259         }
 260
 261         return id;
 262 }
 263
 264 /* Only true for ioctl methods */
 265 static inline __attribute_const__ bool uapi_key_is_attr(u32 key)
 266 {
 267         unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;
 268
 269         return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
 270                (key & UVERBS_API_ATTR_KEY_MASK) != 0;
 271 }
 272
 273 /*
 274  * This returns a value in the range [0 to UVERBS_API_ATTR_BKEY_LEN),
 275  * basically it undoes the reservation of 0 in the ID numbering. attr_key
 276  * must already be masked with UVERBS_API_ATTR_KEY_MASK, or be the output of
 277  * uapi_key_attr().
 278  */
 279 static inline __attribute_const__ u32 uapi_bkey_attr(u32 attr_key)
 280 {
 281         return attr_key - 1;
 282 }
 283
 284 static inline __attribute_const__ u32 uapi_bkey_to_key_attr(u32 attr_bkey)
 285 {
 286         return attr_bkey + 1;
 287 }
 288
 289 /*
 290  * =======================================
 291  *      Verbs definitions
 292  * =======================================
 293  */
 294
 295 struct uverbs_attr_def {
 296         u16                           id;
 297         struct uverbs_attr_spec       attr;
 298 };
 299
 300 struct uverbs_method_def {
 301         u16                                  id;
 302         /* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
 303         u32                                  flags;
 304         size_t                               num_attrs;
 305         const struct uverbs_attr_def * const (*attrs)[];
 306         int (*handler)(struct uverbs_attr_bundle *attrs);
 307 };
 308
 309 struct uverbs_object_def {
 310         u16                                      id;
 311         const struct uverbs_obj_type            *type_attrs;
 312         size_t                                   num_methods;
 313         const struct uverbs_method_def * const (*methods)[];
 314 };
 315
 316 enum uapi_definition_kind {
 317         UAPI_DEF_END = 0,
 318         UAPI_DEF_OBJECT_START,
 319         UAPI_DEF_WRITE,
 320         UAPI_DEF_CHAIN_OBJ_TREE,
 321         UAPI_DEF_CHAIN,
 322         UAPI_DEF_IS_SUPPORTED_FUNC,
 323         UAPI_DEF_IS_SUPPORTED_DEV_FN,
 324 };
 325
 326 enum uapi_definition_scope {
 327         UAPI_SCOPE_OBJECT = 1,
 328         UAPI_SCOPE_METHOD = 2,
 329 };
 330
 331 struct uapi_definition {
 332         u8 kind;
 333         u8 scope;
 334         union {
 335                 struct {
 336                         u16 object_id;
 337                 } object_start;
 338                 struct {
 339                         u16 command_num;
 340                         u8 is_ex:1;
 341                         u8 has_udata:1;
 342                         u8 has_resp:1;
 343                         u8 req_size;
 344                         u8 resp_size;
 345                 } write;
 346         };
 347
 348         union {
 349                 bool (*func_is_supported)(struct ib_device *device);
 350                 int (*func_write)(struct uverbs_attr_bundle *attrs);
 351                 const struct uapi_definition *chain;
 352                 const struct uverbs_object_def *chain_obj_tree;
 353                 size_t needs_fn_offset;
 354         };
 355 };
 356
 357 /* Define things connected to object_id */
 358 #define DECLARE_UVERBS_OBJECT(_object_id, ...)                                 \
 359         {                                                                      \
 360                 .kind = UAPI_DEF_OBJECT_START,                                 \
 361                 .object_start = { .object_id = _object_id },                   \
 362         },                                                                     \
 363                 ##__VA_ARGS__
 364
 365 /* Use in a var_args of DECLARE_UVERBS_OBJECT */
 366 #define DECLARE_UVERBS_WRITE(_command_num, _func, _cmd_desc, ...)              \
 367         {                                                                      \
 368                 .kind = UAPI_DEF_WRITE,                                        \
 369                 .scope = UAPI_SCOPE_OBJECT,                                    \
 370                 .write = { .is_ex = 0, .command_num = _command_num },          \
 371                 .func_write = _func,                                           \
 372                 _cmd_desc,                                                     \
 373         },                                                                     \
 374                 ##__VA_ARGS__
 375
 376 /* Use in a var_args of DECLARE_UVERBS_OBJECT */
 377 #define DECLARE_UVERBS_WRITE_EX(_command_num, _func, _cmd_desc, ...)           \
 378         {                                                                      \
 379                 .kind = UAPI_DEF_WRITE,                                        \
 380                 .scope = UAPI_SCOPE_OBJECT,                                    \
 381                 .write = { .is_ex = 1, .command_num = _command_num },          \
 382                 .func_write = _func,                                           \
 383                 _cmd_desc,                                                     \
 384         },                                                                     \
 385                 ##__VA_ARGS__
 386
 387 /*
 388  * Object is only supported if the function pointer named ibdev_fn in struct
 389  * ib_device is not NULL.
 390  */
 391 #define UAPI_DEF_OBJ_NEEDS_FN(ibdev_fn)                                        \
 392         {                                                                      \
 393                 .kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
 394                 .scope = UAPI_SCOPE_OBJECT,                                    \
 395                 .needs_fn_offset =                                             \
 396                         offsetof(struct ib_device_ops, ibdev_fn) +             \
 397                         BUILD_BUG_ON_ZERO(sizeof_field(struct ib_device_ops,   \
 398                                                        ibdev_fn) !=            \
 399                                           sizeof(void *)),                     \
 400         }
 401
 402 /*
 403  * Method is only supported if the function pointer named ibdev_fn in struct
 404  * ib_device is not NULL.
 405  */
 406 #define UAPI_DEF_METHOD_NEEDS_FN(ibdev_fn)                                     \
 407         {                                                                      \
 408                 .kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
 409                 .scope = UAPI_SCOPE_METHOD,                                    \
 410                 .needs_fn_offset =                                             \
 411                         offsetof(struct ib_device_ops, ibdev_fn) +             \
 412                         BUILD_BUG_ON_ZERO(sizeof_field(struct ib_device_ops,   \
 413                                                        ibdev_fn) !=            \
 414                                           sizeof(void *)),                     \
 415         }
 416
 417 /* Call a function to determine if the entire object is supported or not */
 418 #define UAPI_DEF_IS_OBJ_SUPPORTED(_func)                                       \
 419         {                                                                      \
 420                 .kind = UAPI_DEF_IS_SUPPORTED_FUNC,                            \
 421                 .scope = UAPI_SCOPE_OBJECT, .func_is_supported = _func,        \
 422         }
 423
 424 /* Include another struct uapi_definition in this one */
 425 #define UAPI_DEF_CHAIN(_def_var)                                               \
 426         {                                                                      \
 427                 .kind = UAPI_DEF_CHAIN, .chain = _def_var,                     \
 428         }
 429
 430 /* Temporary until the tree base description is replaced */
 431 #define UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, _object_ptr, ...)                \
 432         {                                                                      \
 433                 .kind = UAPI_DEF_CHAIN_OBJ_TREE,                               \
 434                 .object_start = { .object_id = _object_enum },                 \
 435                 .chain_obj_tree = _object_ptr,                                 \
 436         },                                                                     \
 437                 ##__VA_ARGS__
 438 #define UAPI_DEF_CHAIN_OBJ_TREE_NAMED(_object_enum, ...)                       \
 439         UAPI_DEF_CHAIN_OBJ_TREE(_object_enum,                                  \
 440                 PTR_IF(IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS),              \
 441                        &UVERBS_OBJECT(_object_enum)),                          \
 442                 ##__VA_ARGS__)
 443
 444 /*
 445  * =======================================
 446  *      Attribute Specifications
 447  * =======================================
 448  */
 449
 450 #define UVERBS_ATTR_SIZE(_min_len, _len)                        \
 451         .u.ptr.min_len = _min_len, .u.ptr.len = _len
 452
 453 #define UVERBS_ATTR_NO_DATA() UVERBS_ATTR_SIZE(0, 0)
 454
 455 /*
 456  * Specifies a uapi structure that cannot be extended. The user must always
 457  * supply the whole structure and nothing more. The structure must be declared
 458  * in a header under include/uapi/rdma.
 459  */
 460 #define UVERBS_ATTR_TYPE(_type)                                 \
 461         .u.ptr.min_len = sizeof(_type), .u.ptr.len = sizeof(_type)
 462 /*
 463  * Specifies a uapi structure where the user must provide at least up to
 464  * member 'last'.  Anything after last and up until the end of the structure
 465  * can be non-zero, anything longer than the end of the structure must be
 466  * zero. The structure must be declared in a header under include/uapi/rdma.
 467  */
 468 #define UVERBS_ATTR_STRUCT(_type, _last)                                       \
 469         .zero_trailing = 1,                                                    \
 470         UVERBS_ATTR_SIZE(offsetofend(_type, _last), sizeof(_type))
 471 /*
 472  * Specifies at least min_len bytes must be passed in, but the amount can be
 473  * larger, up to the protocol maximum size. No check for zeroing is done.
 474  */
 475 #define UVERBS_ATTR_MIN_SIZE(_min_len) UVERBS_ATTR_SIZE(_min_len, USHRT_MAX)
 476
 477 /* Must be used in the '...' of any UVERBS_ATTR */
 478 #define UA_ALLOC_AND_COPY .alloc_and_copy = 1
 479 #define UA_MANDATORY .mandatory = 1
 480 #define UA_OPTIONAL .mandatory = 0
 481
 482 /*
 483  * min_len must be bigger than 0 and _max_len must be smaller than 4095.  Only
 484  * READ\WRITE accesses are supported.
 485  */
 486 #define UVERBS_ATTR_IDRS_ARR(_attr_id, _idr_type, _access, _min_len, _max_len, \
 487                              ...)                                              \
 488         (&(const struct uverbs_attr_def){                                      \
 489                 .id = (_attr_id) +                                             \
 490                       BUILD_BUG_ON_ZERO((_min_len) == 0 ||                     \
 491                                         (_max_len) >                           \
 492                                                 PAGE_SIZE / sizeof(void *) ||  \
 493                                         (_min_len) > (_max_len) ||             \
 494                                         (_access) == UVERBS_ACCESS_NEW ||      \
 495                                         (_access) == UVERBS_ACCESS_DESTROY),   \
 496                 .attr = { .type = UVERBS_ATTR_TYPE_IDRS_ARRAY,                 \
 497                           .u2.objs_arr.obj_type = _idr_type,                   \
 498                           .u2.objs_arr.access = _access,                       \
 499                           .u2.objs_arr.min_len = _min_len,                     \
 500                           .u2.objs_arr.max_len = _max_len,                     \
 501                           __VA_ARGS__ } })
 502
 503 /*
 504  * Only for use with UVERBS_ATTR_IDR, allows any uobject type to be accepted,
 505  * the user must validate the type of the uobject instead.
 506  */
 507 #define UVERBS_IDR_ANY_OBJECT 0xFFFF
 508
 509 #define UVERBS_ATTR_IDR(_attr_id, _idr_type, _access, ...)                     \
 510         (&(const struct uverbs_attr_def){                                      \
 511                 .id = _attr_id,                                                \
 512                 .attr = { .type = UVERBS_ATTR_TYPE_IDR,                        \
 513                           .u.obj.obj_type = _idr_type,                         \
 514                           .u.obj.access = _access,                             \
 515                           __VA_ARGS__ } })
 516
 517 #define UVERBS_ATTR_FD(_attr_id, _fd_type, _access, ...)                       \
 518         (&(const struct uverbs_attr_def){                                      \
 519                 .id = (_attr_id) +                                             \
 520                       BUILD_BUG_ON_ZERO((_access) != UVERBS_ACCESS_NEW &&      \
 521                                         (_access) != UVERBS_ACCESS_READ),      \
 522                 .attr = { .type = UVERBS_ATTR_TYPE_FD,                         \
 523                           .u.obj.obj_type = _fd_type,                          \
 524                           .u.obj.access = _access,                             \
 525                           __VA_ARGS__ } })
 526
 527 #define UVERBS_ATTR_RAW_FD(_attr_id, ...)                                      \
 528         (&(const struct uverbs_attr_def){                                      \
 529                 .id = (_attr_id),                                              \
 530                 .attr = { .type = UVERBS_ATTR_TYPE_RAW_FD, __VA_ARGS__ } })
 531
 532 #define UVERBS_ATTR_PTR_IN(_attr_id, _type, ...)                               \
 533         (&(const struct uverbs_attr_def){                                      \
 534                 .id = _attr_id,                                                \
 535                 .attr = { .type = UVERBS_ATTR_TYPE_PTR_IN,                     \
 536                           _type,                                               \
 537                           __VA_ARGS__ } })
 538
 539 #define UVERBS_ATTR_PTR_OUT(_attr_id, _type, ...)                              \
 540         (&(const struct uverbs_attr_def){                                      \
 541                 .id = _attr_id,                                                \
 542                 .attr = { .type = UVERBS_ATTR_TYPE_PTR_OUT,                    \
 543                           _type,                                               \
 544                           __VA_ARGS__ } })
 545
 546 /* _enum_arry should be a 'static const union uverbs_attr_spec[]' */
 547 #define UVERBS_ATTR_ENUM_IN(_attr_id, _enum_arr, ...)                          \
 548         (&(const struct uverbs_attr_def){                                      \
 549                 .id = _attr_id,                                                \
 550                 .attr = { .type = UVERBS_ATTR_TYPE_ENUM_IN,                    \
 551                           .u2.enum_def.ids = _enum_arr,                        \
 552                           .u.enum_def.num_elems = ARRAY_SIZE(_enum_arr),       \
 553                           __VA_ARGS__ },                                       \
 554         })
 555
 556 /* An input value that is a member in the enum _enum_type. */
 557 #define UVERBS_ATTR_CONST_IN(_attr_id, _enum_type, ...)                        \
 558         UVERBS_ATTR_PTR_IN(                                                    \
 559                 _attr_id,                                                      \
 560                 UVERBS_ATTR_SIZE(                                              \
 561                         sizeof(u64) + BUILD_BUG_ON_ZERO(!sizeof(_enum_type)),  \
 562                         sizeof(u64)),                                          \
 563                 __VA_ARGS__)
 564
 565 /*
 566  * An input value that is a bitwise combination of values of _enum_type.
 567  * This permits the flag value to be passed as either a u32 or u64, it must
 568  * be retrieved via uverbs_get_flag().
 569  */
 570 #define UVERBS_ATTR_FLAGS_IN(_attr_id, _enum_type, ...)                        \
 571         UVERBS_ATTR_PTR_IN(                                                    \
 572                 _attr_id,                                                      \
 573                 UVERBS_ATTR_SIZE(sizeof(u32) + BUILD_BUG_ON_ZERO(              \
 574                                                        !sizeof(_enum_type *)), \
 575                                  sizeof(u64)),                                 \
 576                 __VA_ARGS__)
 577
 578 /*
 579  * This spec is used in order to pass information to the hardware driver in a
 580  * legacy way. Every verb that could get driver specific data should get this
 581  * spec.
 582  */
 583 #define UVERBS_ATTR_UHW()                                                      \
 584         UVERBS_ATTR_PTR_IN(UVERBS_ATTR_UHW_IN,                                 \
 585                            UVERBS_ATTR_MIN_SIZE(0),                            \
 586                            UA_OPTIONAL,                                        \
 587                            .is_udata = 1),                                     \
 588         UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT,                               \
 589                             UVERBS_ATTR_MIN_SIZE(0),                           \
 590                             UA_OPTIONAL,                                       \
 591                             .is_udata = 1)
 592
 593 /* =================================================
 594  *              Parsing infrastructure
 595  * =================================================
 596  */
 597
 598
 599 struct uverbs_ptr_attr {
 600         /*
 601          * If UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY is set then the 'ptr' is
 602          * used.
 603          */
 604         union {
 605                 void *ptr;
 606                 u64 data;
 607         };
 608         u16             len;
 609         u16             uattr_idx;
 610         u8              enum_id;
 611 };
 612
 613 struct uverbs_obj_attr {
 614         struct ib_uobject               *uobject;
 615         const struct uverbs_api_attr    *attr_elm;
 616 };
 617
 618 struct uverbs_objs_arr_attr {
 619         struct ib_uobject **uobjects;
 620         u16 len;
 621 };
 622
 623 struct uverbs_attr {
 624         union {
 625                 struct uverbs_ptr_attr  ptr_attr;
 626                 struct uverbs_obj_attr  obj_attr;
 627                 struct uverbs_objs_arr_attr objs_arr_attr;
 628         };
 629 };
 630
 631 struct uverbs_attr_bundle {
 632         struct ib_udata driver_udata;
 633         struct ib_udata ucore;
 634         struct ib_uverbs_file *ufile;
 635         struct ib_ucontext *context;
 636         struct ib_uobject *uobject;
 637         DECLARE_BITMAP(attr_present, UVERBS_API_ATTR_BKEY_LEN);
 638         struct uverbs_attr attrs[];
 639 };
 640
 641 static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
 642                                         unsigned int idx)
 643 {
 644         return test_bit(uapi_bkey_attr(uapi_key_attr(idx)),
 645                         attrs_bundle->attr_present);
 646 }
 647
 648 /**
 649  * rdma_udata_to_drv_context - Helper macro to get the driver's context out of
 650  *                             ib_udata which is embedded in uverbs_attr_bundle.
 651  *
 652  * If udata is not NULL this cannot fail. Otherwise a NULL udata will result
 653  * in a NULL ucontext pointer, as a safety precaution. Callers should be using
 654  * 'udata' to determine if the driver call is in user or kernel mode, not
 655  * 'ucontext'.
 656  *
 657  */
 658 static inline struct uverbs_attr_bundle *
 659 rdma_udata_to_uverbs_attr_bundle(struct ib_udata *udata)
 660 {
 661         return container_of(udata, struct uverbs_attr_bundle, driver_udata);
 662 }
 663
 664 #define rdma_udata_to_drv_context(udata, drv_dev_struct, member)                \
 665         (udata ? container_of(rdma_udata_to_uverbs_attr_bundle(udata)->context, \
 666                               drv_dev_struct, member) : (drv_dev_struct *)NULL)
 667
 668 #define IS_UVERBS_COPY_ERR(_ret)                ((_ret) && (_ret) != -ENOENT)
 669
 670 static inline const struct uverbs_attr *uverbs_attr_get(const struct uverbs_attr_bundle *attrs_bundle,
 671                                                         u16 idx)
 672 {
 673         if (!uverbs_attr_is_valid(attrs_bundle, idx))
 674                 return ERR_PTR(-ENOENT);
 675
 676         return &attrs_bundle->attrs[uapi_bkey_attr(uapi_key_attr(idx))];
 677 }
 678
 679 static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle,
 680                                           u16 idx)
 681 {
 682         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 683
 684         if (IS_ERR(attr))
 685                 return PTR_ERR(attr);
 686
 687         return attr->ptr_attr.enum_id;
 688 }
 689
 690 static inline void *uverbs_attr_get_obj(const struct uverbs_attr_bundle *attrs_bundle,
 691                                         u16 idx)
 692 {
 693         const struct uverbs_attr *attr;
 694
 695         attr = uverbs_attr_get(attrs_bundle, idx);
 696         if (IS_ERR(attr))
 697                 return ERR_CAST(attr);
 698
 699         return attr->obj_attr.uobject->object;
 700 }
 701
 702 static inline struct ib_uobject *uverbs_attr_get_uobject(const struct uverbs_attr_bundle *attrs_bundle,
 703                                                          u16 idx)
 704 {
 705         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 706
 707         if (IS_ERR(attr))
 708                 return ERR_CAST(attr);
 709
 710         return attr->obj_attr.uobject;
 711 }
 712
 713 static inline int
 714 uverbs_attr_get_len(const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
 715 {
 716         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 717
 718         if (IS_ERR(attr))
 719                 return PTR_ERR(attr);
 720
 721         return attr->ptr_attr.len;
 722 }
 723
 724 void uverbs_finalize_uobj_create(const struct uverbs_attr_bundle *attrs_bundle,
 725                                  u16 idx);
 726
 727 /*
 728  * uverbs_attr_ptr_get_array_size() - Get array size pointer by a ptr
 729  * attribute.
 730  * @attrs: The attribute bundle
 731  * @idx: The ID of the attribute
 732  * @elem_size: The size of the element in the array
 733  */
 734 static inline int
 735 uverbs_attr_ptr_get_array_size(struct uverbs_attr_bundle *attrs, u16 idx,
 736                                size_t elem_size)
 737 {
 738         int size = uverbs_attr_get_len(attrs, idx);
 739
 740         if (size < 0)
 741                 return size;
 742
 743         if (size % elem_size)
 744                 return -EINVAL;
 745
 746         return size / elem_size;
 747 }
 748
 749 /**
 750  * uverbs_attr_get_uobjs_arr() - Provides array's properties for attribute for
 751  * UVERBS_ATTR_TYPE_IDRS_ARRAY.
 752  * @arr: Returned pointer to array of pointers for uobjects or NULL if
 753  *       the attribute isn't provided.
 754  *
 755  * Return: The array length or 0 if no attribute was provided.
 756  */
 757 static inline int uverbs_attr_get_uobjs_arr(
 758         const struct uverbs_attr_bundle *attrs_bundle, u16 attr_idx,
 759         struct ib_uobject ***arr)
 760 {
 761         const struct uverbs_attr *attr =
 762                         uverbs_attr_get(attrs_bundle, attr_idx);
 763
 764         if (IS_ERR(attr)) {
 765                 *arr = NULL;
 766                 return 0;
 767         }
 768
 769         *arr = attr->objs_arr_attr.uobjects;
 770
 771         return attr->objs_arr_attr.len;
 772 }
 773
 774 static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr)
 775 {
 776         return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data);
 777 }
 778
 779 static inline void *uverbs_attr_get_alloced_ptr(
 780         const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
 781 {
 782         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 783
 784         if (IS_ERR(attr))
 785                 return (void *)attr;
 786
 787         return uverbs_attr_ptr_is_inline(attr) ? (void *)&attr->ptr_attr.data :
 788                                                  attr->ptr_attr.ptr;
 789 }
 790
 791 static inline int _uverbs_copy_from(void *to,
 792                                     const struct uverbs_attr_bundle *attrs_bundle,
 793                                     size_t idx,
 794                                     size_t size)
 795 {
 796         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 797
 798         if (IS_ERR(attr))
 799                 return PTR_ERR(attr);
 800
 801         /*
 802          * Validation ensures attr->ptr_attr.len >= size. If the caller is
 803          * using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call
 804          * uverbs_copy_from_or_zero.
 805          */
 806         if (unlikely(size < attr->ptr_attr.len))
 807                 return -EINVAL;
 808
 809         if (uverbs_attr_ptr_is_inline(attr))
 810                 memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
 811         else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
 812                                 attr->ptr_attr.len))
 813                 return -EFAULT;
 814
 815         return 0;
 816 }
 817
 818 static inline int _uverbs_copy_from_or_zero(void *to,
 819                                             const struct uverbs_attr_bundle *attrs_bundle,
 820                                             size_t idx,
 821                                             size_t size)
 822 {
 823         const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
 824         size_t min_size;
 825
 826         if (IS_ERR(attr))
 827                 return PTR_ERR(attr);
 828
 829         min_size = min_t(size_t, size, attr->ptr_attr.len);
 830
 831         if (uverbs_attr_ptr_is_inline(attr))
 832                 memcpy(to, &attr->ptr_attr.data, min_size);
 833         else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
 834                                 min_size))
 835                 return -EFAULT;
 836
 837         if (size > min_size)
 838                 memset(to + min_size, 0, size - min_size);
 839
 840         return 0;
 841 }
 842
 843 #define uverbs_copy_from(to, attrs_bundle, idx)                               \
 844         _uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to))
 845
 846 #define uverbs_copy_from_or_zero(to, attrs_bundle, idx)                       \
 847         _uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to))
 848
 849 static inline struct ib_ucontext *
 850 ib_uverbs_get_ucontext(const struct uverbs_attr_bundle *attrs)
 851 {
 852         return ib_uverbs_get_ucontext_file(attrs->ufile);
 853 }
 854
 855 #if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
 856 int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 857                        size_t idx, u64 allowed_bits);
 858 int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
 859                        size_t idx, u64 allowed_bits);
 860 int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle, size_t idx,
 861                    const void *from, size_t size);
 862 __malloc void *_uverbs_alloc(struct uverbs_attr_bundle *bundle, size_t size,
 863                              gfp_t flags);
 864
 865 static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
 866                                           size_t size)
 867 {
 868         return _uverbs_alloc(bundle, size, GFP_KERNEL);
 869 }
 870
 871 static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
 872                                            size_t size)
 873 {
 874         return _uverbs_alloc(bundle, size, GFP_KERNEL | __GFP_ZERO);
 875 }
 876
 877 static inline __malloc void *uverbs_kcalloc(struct uverbs_attr_bundle *bundle,
 878                                             size_t n, size_t size)
 879 {
 880         size_t bytes;
 881
 882         if (unlikely(check_mul_overflow(n, size, &bytes)))
 883                 return ERR_PTR(-EOVERFLOW);
 884         return uverbs_zalloc(bundle, bytes);
 885 }
 886
 887 int _uverbs_get_const_signed(s64 *to,
 888                              const struct uverbs_attr_bundle *attrs_bundle,
 889                              size_t idx, s64 lower_bound, u64 upper_bound,
 890                              s64 *def_val);
 891 int _uverbs_get_const_unsigned(u64 *to,
 892                                const struct uverbs_attr_bundle *attrs_bundle,
 893                                size_t idx, u64 upper_bound, u64 *def_val);
 894 int uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
 895                                   size_t idx, const void *from, size_t size);
 896 #else
 897 static inline int
 898 uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 899                    size_t idx, u64 allowed_bits)
 900 {
 901         return -EINVAL;
 902 }
 903 static inline int
 904 uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
 905                    size_t idx, u64 allowed_bits)
 906 {
 907         return -EINVAL;
 908 }
 909 static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
 910                                  size_t idx, const void *from, size_t size)
 911 {
 912         return -EINVAL;
 913 }
 914 static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
 915                                           size_t size)
 916 {
 917         return ERR_PTR(-EINVAL);
 918 }
 919 static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
 920                                            size_t size)
 921 {
 922         return ERR_PTR(-EINVAL);
 923 }
 924 static inline int
 925 _uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
 926                   size_t idx, s64 lower_bound, u64 upper_bound,
 927                   s64 *def_val)
 928 {
 929         return -EINVAL;
 930 }
 931 static inline int
 932 uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
 933                               size_t idx, const void *from, size_t size)
 934 {
 935         return -EINVAL;
 936 }
 937 static inline int
 938 _uverbs_get_const_signed(s64 *to,
 939                          const struct uverbs_attr_bundle *attrs_bundle,
 940                          size_t idx, s64 lower_bound, u64 upper_bound,
 941                          s64 *def_val)
 942 {
 943         return -EINVAL;
 944 }
 945 static inline int
 946 _uverbs_get_const_unsigned(u64 *to,
 947                            const struct uverbs_attr_bundle *attrs_bundle,
 948                            size_t idx, u64 upper_bound, u64 *def_val)
 949 {
 950         return -EINVAL;
 951 }
 952 #endif
 953
 954 #define uverbs_get_const_signed(_to, _attrs_bundle, _idx)                      \
 955         ({                                                                     \
 956                 s64 _val;                                                      \
 957                 int _ret =                                                     \
 958                         _uverbs_get_const_signed(&_val, _attrs_bundle, _idx,   \
 959                                           type_min(typeof(*(_to))),            \
 960                                           type_max(typeof(*(_to))), NULL);     \
 961                 (*(_to)) = _val;                                               \
 962                 _ret;                                                          \
 963         })
 964
 965 #define uverbs_get_const_unsigned(_to, _attrs_bundle, _idx)                    \
 966         ({                                                                     \
 967                 u64 _val;                                                      \
 968                 int _ret =                                                     \
 969                         _uverbs_get_const_unsigned(&_val, _attrs_bundle, _idx, \
 970                                           type_max(typeof(*(_to))), NULL);     \
 971                 (*(_to)) = _val;                                               \
 972                 _ret;                                                          \
 973         })
 974
 975 #define uverbs_get_const_default_signed(_to, _attrs_bundle, _idx, _default)    \
 976         ({                                                                     \
 977                 s64 _val;                                                      \
 978                 s64 _def_val = _default;                                       \
 979                 int _ret =                                                     \
 980                         _uverbs_get_const_signed(&_val, _attrs_bundle, _idx,   \
 981                                 type_min(typeof(*(_to))),                      \
 982                                 type_max(typeof(*(_to))), &_def_val);          \
 983                 (*(_to)) = _val;                                               \
 984                 _ret;                                                          \
 985         })
 986
 987 #define uverbs_get_const_default_unsigned(_to, _attrs_bundle, _idx, _default)  \
 988         ({                                                                     \
 989                 u64 _val;                                                      \
 990                 u64 _def_val = _default;                                       \
 991                 int _ret =                                                     \
 992                         _uverbs_get_const_unsigned(&_val, _attrs_bundle, _idx, \
 993                                 type_max(typeof(*(_to))), &_def_val);          \
 994                 (*(_to)) = _val;                                               \
 995                 _ret;                                                          \
 996         })
 997
 998 #define uverbs_get_const(_to, _attrs_bundle, _idx)                             \
 999         (is_signed_type(typeof(*(_to))) ?                                      \
1000                  uverbs_get_const_signed(_to, _attrs_bundle, _idx) :           \
1001                  uverbs_get_const_unsigned(_to, _attrs_bundle, _idx))          \
1002
1003 #define uverbs_get_const_default(_to, _attrs_bundle, _idx, _default)           \
1004         (is_signed_type(typeof(*(_to))) ?                                      \
1005                  uverbs_get_const_default_signed(_to, _attrs_bundle, _idx,     \
1006                                                   _default) :                  \
1007                  uverbs_get_const_default_unsigned(_to, _attrs_bundle, _idx,   \
1008                                                     _default))
1009
1010 static inline int
1011 uverbs_get_raw_fd(int *to, const struct uverbs_attr_bundle *attrs_bundle,
1012                   size_t idx)
1013 {
1014         return uverbs_get_const_signed(to, attrs_bundle, idx);
1015 }
1016
1017 #endif