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_TYPES_ 7 #define _UVERBS_TYPES_ 8 9 #include <linux/kernel.h> 10 #include <rdma/ib_verbs.h> 11 12 struct uverbs_obj_type; 13 struct uverbs_api_object; 14 15 enum rdma_lookup_mode { 16 UVERBS_LOOKUP_READ, 17 UVERBS_LOOKUP_WRITE, 18 /* 19 * Destroy is like LOOKUP_WRITE, except that the uobject is not 20 * locked. uobj_destroy is used to convert a LOOKUP_DESTROY lock into 21 * a LOOKUP_WRITE lock. 22 */ 23 UVERBS_LOOKUP_DESTROY, 24 }; 25 26 /* 27 * The following sequences are valid: 28 * Success flow: 29 * alloc_begin 30 * alloc_commit 31 * [..] 32 * Access flow: 33 * lookup_get(exclusive=false) & uverbs_try_lock_object 34 * lookup_put(exclusive=false) via rdma_lookup_put_uobject 35 * Destruction flow: 36 * lookup_get(exclusive=true) & uverbs_try_lock_object 37 * remove_commit 38 * remove_handle (optional) 39 * lookup_put(exclusive=true) via rdma_lookup_put_uobject 40 * 41 * Allocate Error flow #1 42 * alloc_begin 43 * alloc_abort 44 * Allocate Error flow #2 45 * alloc_begin 46 * remove_commit 47 * alloc_abort 48 * Allocate Error flow #3 49 * alloc_begin 50 * alloc_commit (fails) 51 * remove_commit 52 * alloc_abort 53 * 54 * In all cases the caller must hold the ufile kref until alloc_commit or 55 * alloc_abort returns. 56 */ 57 struct uverbs_obj_type_class { 58 struct ib_uobject *(*alloc_begin)(const struct uverbs_api_object *obj, 59 struct uverbs_attr_bundle *attrs); 60 /* This consumes the kref on uobj */ 61 void (*alloc_commit)(struct ib_uobject *uobj); 62 /* This does not consume the kref on uobj */ 63 void (*alloc_abort)(struct ib_uobject *uobj); 64 65 struct ib_uobject *(*lookup_get)(const struct uverbs_api_object *obj, 66 struct ib_uverbs_file *ufile, s64 id, 67 enum rdma_lookup_mode mode); 68 void (*lookup_put)(struct ib_uobject *uobj, enum rdma_lookup_mode mode); 69 /* This does not consume the kref on uobj */ 70 int __must_check (*destroy_hw)(struct ib_uobject *uobj, 71 enum rdma_remove_reason why, 72 struct uverbs_attr_bundle *attrs); 73 void (*remove_handle)(struct ib_uobject *uobj); 74 void (*swap_uobjects)(struct ib_uobject *obj_old, 75 struct ib_uobject *obj_new); 76 }; 77 78 struct uverbs_obj_type { 79 const struct uverbs_obj_type_class * const type_class; 80 size_t obj_size; 81 }; 82 83 /* 84 * Objects type classes which support a detach state (object is still alive but 85 * it's not attached to any context need to make sure: 86 * (a) no call through to a driver after a detach is called 87 * (b) detach isn't called concurrently with context_cleanup 88 */ 89 90 struct uverbs_obj_idr_type { 91 /* 92 * In idr based objects, uverbs_obj_type_class points to a generic 93 * idr operations. In order to specialize the underlying types (e.g. CQ, 94 * QPs, etc.), we add destroy_object specific callbacks. 95 */ 96 struct uverbs_obj_type type; 97 98 /* Free driver resources from the uobject, make the driver uncallable, 99 * and move the uobject to the detached state. If the object was 100 * destroyed by the user's request, a failure should leave the uobject 101 * completely unchanged. 102 */ 103 int __must_check (*destroy_object)(struct ib_uobject *uobj, 104 enum rdma_remove_reason why, 105 struct uverbs_attr_bundle *attrs); 106 }; 107 108 struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_api_object *obj, 109 struct ib_uverbs_file *ufile, s64 id, 110 enum rdma_lookup_mode mode, 111 struct uverbs_attr_bundle *attrs); 112 void rdma_lookup_put_uobject(struct ib_uobject *uobj, 113 enum rdma_lookup_mode mode); 114 struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_api_object *obj, 115 struct uverbs_attr_bundle *attrs); 116 void rdma_alloc_abort_uobject(struct ib_uobject *uobj, 117 struct uverbs_attr_bundle *attrs, 118 bool hw_obj_valid); 119 void rdma_alloc_commit_uobject(struct ib_uobject *uobj, 120 struct uverbs_attr_bundle *attrs); 121 void rdma_assign_uobject(struct ib_uobject *to_uobj, 122 struct ib_uobject *new_uobj, 123 struct uverbs_attr_bundle *attrs); 124 125 /* 126 * uverbs_uobject_get is called in order to increase the reference count on 127 * an uobject. This is useful when a handler wants to keep the uobject's memory 128 * alive, regardless if this uobject is still alive in the context's objects 129 * repository. Objects are put via uverbs_uobject_put. 130 */ 131 static inline void uverbs_uobject_get(struct ib_uobject *uobject) 132 { 133 kref_get(&uobject->ref); 134 } 135 void uverbs_uobject_put(struct ib_uobject *uobject); 136 137 int uverbs_try_lock_object(struct ib_uobject *uobj, enum rdma_lookup_mode mode); 138 139 struct uverbs_obj_fd_type { 140 /* 141 * In fd based objects, uverbs_obj_type_ops points to generic 142 * fd operations. In order to specialize the underlying types (e.g. 143 * completion_channel), we use fops, name and flags for fd creation. 144 * destroy_object is called when the uobject is to be destroyed, 145 * because the driver is removed or the FD is closed. 146 */ 147 struct uverbs_obj_type type; 148 void (*destroy_object)(struct ib_uobject *uobj, 149 enum rdma_remove_reason why); 150 const struct file_operations *fops; 151 const char *name; 152 int flags; 153 }; 154 155 struct ib_uverbs_file { 156 struct kref ref; 157 struct ib_uverbs_device *device; 158 struct mutex ucontext_lock; 159 /* 160 * ucontext must be accessed via ib_uverbs_get_ucontext() or with 161 * ucontext_lock held 162 */ 163 struct ib_ucontext *ucontext; 164 struct ib_uverbs_async_event_file *default_async_file; 165 struct list_head list; 166 167 /* 168 * To access the uobjects list hw_destroy_rwsem must be held for write 169 * OR hw_destroy_rwsem held for read AND uobjects_lock held. 170 * hw_destroy_rwsem should be called across any destruction of the HW 171 * object of an associated uobject. 172 */ 173 struct rw_semaphore hw_destroy_rwsem; 174 spinlock_t uobjects_lock; 175 struct list_head uobjects; 176 177 struct mutex umap_lock; 178 struct list_head umaps; 179 struct page *disassociate_page; 180 181 struct xarray idr; 182 183 struct mutex disassociation_lock; 184 }; 185 186 extern const struct uverbs_obj_type_class uverbs_idr_class; 187 extern const struct uverbs_obj_type_class uverbs_fd_class; 188 int uverbs_uobject_fd_release(struct inode *inode, struct file *filp); 189 190 #define UVERBS_BUILD_BUG_ON(cond) (sizeof(char[1 - 2 * !!(cond)]) - \ 191 sizeof(char)) 192 #define UVERBS_TYPE_ALLOC_FD(_obj_size, _destroy_object, _fops, _name, _flags) \ 193 ((&((const struct uverbs_obj_fd_type) \ 194 {.type = { \ 195 .type_class = &uverbs_fd_class, \ 196 .obj_size = (_obj_size) + \ 197 UVERBS_BUILD_BUG_ON((_obj_size) < \ 198 sizeof(struct ib_uobject)), \ 199 }, \ 200 .destroy_object = _destroy_object, \ 201 .fops = _fops, \ 202 .name = _name, \ 203 .flags = _flags}))->type) 204 #define UVERBS_TYPE_ALLOC_IDR_SZ(_size, _destroy_object) \ 205 ((&((const struct uverbs_obj_idr_type) \ 206 {.type = { \ 207 .type_class = &uverbs_idr_class, \ 208 .obj_size = (_size) + \ 209 UVERBS_BUILD_BUG_ON((_size) < \ 210 sizeof(struct ib_uobject)) \ 211 }, \ 212 .destroy_object = _destroy_object,}))->type) 213 #define UVERBS_TYPE_ALLOC_IDR(_destroy_object) \ 214 UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uobject), \ 215 _destroy_object) 216 217 #endif 218