diff options
Diffstat (limited to 'include/rdma/uverbs_types.h')
| -rw-r--r-- | include/rdma/uverbs_types.h | 70 |
1 files changed, 33 insertions, 37 deletions
diff --git a/include/rdma/uverbs_types.h b/include/rdma/uverbs_types.h index 8bae28dd2e4f..875dd8c16ba3 100644 --- a/include/rdma/uverbs_types.h +++ b/include/rdma/uverbs_types.h @@ -38,53 +38,49 @@ struct uverbs_obj_type; +/* + * The following sequences are valid: + * Success flow: + * alloc_begin + * alloc_commit + * [..] + * Access flow: + * lookup_get(exclusive=false) & uverbs_try_lock_object + * lookup_put(exclusive=false) via rdma_lookup_put_uobject + * Destruction flow: + * lookup_get(exclusive=true) & uverbs_try_lock_object + * remove_commit + * lookup_put(exclusive=true) via rdma_lookup_put_uobject + * + * Allocate Error flow #1 + * alloc_begin + * alloc_abort + * Allocate Error flow #2 + * alloc_begin + * remove_commit + * alloc_abort + * Allocate Error flow #3 + * alloc_begin + * alloc_commit (fails) + * remove_commit + * alloc_abort + * + * In all cases the caller must hold the ufile kref until alloc_commit or + * alloc_abort returns. + */ struct uverbs_obj_type_class { - /* - * Get an ib_uobject that corresponds to the given id from ucontext, - * These functions could create or destroy objects if required. - * The action will be finalized only when commit, abort or put fops are - * called. - * The flow of the different actions is: - * [alloc]: Starts with alloc_begin. The handlers logic is than - * executed. If the handler is successful, alloc_commit - * is called and the object is inserted to the repository. - * Once alloc_commit completes the object is visible to - * other threads and userspace. - e Otherwise, alloc_abort is called and the object is - * destroyed. - * [lookup]: Starts with lookup_get which fetches and locks the - * object. After the handler finished using the object, it - * needs to call lookup_put to unlock it. The exclusive - * flag indicates if the object is locked for exclusive - * access. - * [remove]: Starts with lookup_get with exclusive flag set. This - * locks the object for exclusive access. If the handler - * code completed successfully, remove_commit is called - * and the ib_uobject is removed from the context's - * uobjects repository and put. The object itself is - * destroyed as well. Once remove succeeds new krefs to - * the object cannot be acquired by other threads or - * userspace and the hardware driver is removed from the - * object. Other krefs on the object may still exist. - * If the handler code failed, lookup_put should be - * called. This callback is used when the context - * is destroyed as well (process termination, - * reset flow). - */ struct ib_uobject *(*alloc_begin)(const struct uverbs_obj_type *type, struct ib_uverbs_file *ufile); + /* This consumes the kref on uobj */ int (*alloc_commit)(struct ib_uobject *uobj); + /* This does not consume the kref on uobj */ void (*alloc_abort)(struct ib_uobject *uobj); struct ib_uobject *(*lookup_get)(const struct uverbs_obj_type *type, struct ib_uverbs_file *ufile, s64 id, bool exclusive); void (*lookup_put)(struct ib_uobject *uobj, bool exclusive); - /* - * Must be called with the exclusive lock held. If successful uobj is - * invalid on return. On failure uobject is left completely - * unchanged - */ + /* This does not consume the kref on uobj */ int __must_check (*remove_commit)(struct ib_uobject *uobj, enum rdma_remove_reason why); u8 needs_kfree_rcu; |