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_TYPES_ 34 #define _UVERBS_TYPES_ 35 36 #include <linux/kernel.h> 37 #include <rdma/ib_verbs.h> 38 39 struct uverbs_obj_type; 40 41 struct uverbs_obj_type_class { 42 /* 43 * Get an ib_uobject that corresponds to the given id from ucontext, 44 * These functions could create or destroy objects if required. 45 * The action will be finalized only when commit, abort or put fops are 46 * called. 47 * The flow of the different actions is: 48 * [alloc]: Starts with alloc_begin. The handlers logic is than 49 * executed. If the handler is successful, alloc_commit 50 * is called and the object is inserted to the repository. 51 * Once alloc_commit completes the object is visible to 52 * other threads and userspace. 53 e Otherwise, alloc_abort is called and the object is 54 * destroyed. 55 * [lookup]: Starts with lookup_get which fetches and locks the 56 * object. After the handler finished using the object, it 57 * needs to call lookup_put to unlock it. The write flag 58 * indicates if the object is locked for exclusive access. 59 * [remove]: Starts with lookup_get with write flag set. This locks 60 * the object for exclusive access. If the handler code 61 * completed successfully, remove_commit is called and 62 * the ib_uobject is removed from the context's uobjects 63 * repository and put. The object itself is destroyed as 64 * well. Once remove succeeds new krefs to the object 65 * cannot be acquired by other threads or userspace and 66 * the hardware driver is removed from the object. 67 * Other krefs on the object may still exist. 68 * If the handler code failed, lookup_put should be 69 * called. This callback is used when the context 70 * is destroyed as well (process termination, 71 * reset flow). 72 */ 73 struct ib_uobject *(*alloc_begin)(const struct uverbs_obj_type *type, 74 struct ib_ucontext *ucontext); 75 void (*alloc_commit)(struct ib_uobject *uobj); 76 void (*alloc_abort)(struct ib_uobject *uobj); 77 78 struct ib_uobject *(*lookup_get)(const struct uverbs_obj_type *type, 79 struct ib_ucontext *ucontext, int id, 80 bool write); 81 void (*lookup_put)(struct ib_uobject *uobj, bool write); 82 /* 83 * Must be called with the write lock held. If successful uobj is 84 * invalid on return. On failure uobject is left completely 85 * unchanged 86 */ 87 int __must_check (*remove_commit)(struct ib_uobject *uobj, 88 enum rdma_remove_reason why); 89 u8 needs_kfree_rcu; 90 }; 91 92 struct uverbs_obj_type { 93 const struct uverbs_obj_type_class * const type_class; 94 size_t obj_size; 95 unsigned int destroy_order; 96 }; 97 98 /* 99 * Objects type classes which support a detach state (object is still alive but 100 * it's not attached to any context need to make sure: 101 * (a) no call through to a driver after a detach is called 102 * (b) detach isn't called concurrently with context_cleanup 103 */ 104 105 struct uverbs_obj_idr_type { 106 /* 107 * In idr based objects, uverbs_obj_type_class points to a generic 108 * idr operations. In order to specialize the underlying types (e.g. CQ, 109 * QPs, etc.), we add destroy_object specific callbacks. 110 */ 111 struct uverbs_obj_type type; 112 113 /* Free driver resources from the uobject, make the driver uncallable, 114 * and move the uobject to the detached state. If the object was 115 * destroyed by the user's request, a failure should leave the uobject 116 * completely unchanged. 117 */ 118 int __must_check (*destroy_object)(struct ib_uobject *uobj, 119 enum rdma_remove_reason why); 120 }; 121 122 struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_obj_type *type, 123 struct ib_ucontext *ucontext, 124 int id, bool write); 125 void rdma_lookup_put_uobject(struct ib_uobject *uobj, bool write); 126 struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_obj_type *type, 127 struct ib_ucontext *ucontext); 128 void rdma_alloc_abort_uobject(struct ib_uobject *uobj); 129 int __must_check rdma_remove_commit_uobject(struct ib_uobject *uobj); 130 int rdma_alloc_commit_uobject(struct ib_uobject *uobj); 131 132 extern const struct uverbs_obj_type_class uverbs_idr_class; 133 134 #define UVERBS_BUILD_BUG_ON(cond) (sizeof(char[1 - 2 * !!(cond)]) - \ 135 sizeof(char)) 136 #define UVERBS_TYPE_ALLOC_IDR_SZ(_size, _order) \ 137 { \ 138 .destroy_order = _order, \ 139 .type_class = &uverbs_idr_class, \ 140 .obj_size = (_size) + \ 141 UVERBS_BUILD_BUG_ON((_size) < \ 142 sizeof(struct ib_uobject)), \ 143 } 144 #define UVERBS_TYPE_ALLOC_IDR(_order) \ 145 UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uobject), _order) 146 #endif 147