2 * The io parts of the fio tool, includes workers for sync and mmap'ed
3 * io, as well as both posix and linux libaio support.
5 * sync io is implemented on top of aio.
7 * This is not really specific to fio, if the get_io_u/put_io_u and
8 * structures was pulled into this as well it would be a perfectly
9 * generic io engine that could be used for other projects.
21 static LIST_HEAD(engine_list);
23 static int check_engine_ops(struct ioengine_ops *ops)
25 if (ops->version != FIO_IOOPS_VERSION) {
26 log_err("bad ioops version %d (want %d)\n", ops->version, FIO_IOOPS_VERSION);
31 * cpu thread doesn't need to provide anything
33 if (ops->flags & FIO_CPUIO)
37 log_err("%s: no event handler)\n", ops->name);
40 if (!ops->getevents) {
41 log_err("%s: no getevents handler)\n", ops->name);
45 log_err("%s: no queue handler)\n", ops->name);
52 void unregister_ioengine(struct ioengine_ops *ops)
55 INIT_LIST_HEAD(&ops->list);
58 int register_ioengine(struct ioengine_ops *ops)
60 INIT_LIST_HEAD(&ops->list);
61 list_add_tail(&ops->list, &engine_list);
65 static struct ioengine_ops *find_ioengine(const char *name)
67 struct ioengine_ops *ops;
68 struct list_head *entry;
71 strncpy(engine, name, sizeof(engine) - 1);
73 if (!strncmp(engine, "linuxaio", 8) || !strncmp(engine, "aio", 3))
74 strcpy(engine, "libaio");
76 list_for_each(entry, &engine_list) {
77 ops = list_entry(entry, struct ioengine_ops, list);
78 if (!strcmp(engine, ops->name))
85 static struct ioengine_ops *dlopen_ioengine(struct thread_data *td,
86 const char *engine_lib)
88 struct ioengine_ops *ops;
92 dlhandle = dlopen(engine_lib, RTLD_LAZY);
94 td_vmsg(td, -1, dlerror());
99 * Unlike the included modules, external engines should have a
100 * non-static ioengine structure that we can reference.
102 ops = dlsym(dlhandle, "ioengine");
104 td_vmsg(td, -1, dlerror());
109 ops->dlhandle = dlhandle;
113 struct ioengine_ops *load_ioengine(struct thread_data *td, const char *name)
115 struct ioengine_ops *ops, *ret;
118 strncpy(engine, name, sizeof(engine) - 1);
121 * linux libaio has alias names, so convert to what we want
123 if (!strncmp(engine, "linuxaio", 8) || !strncmp(engine, "aio", 3))
124 strcpy(engine, "libaio");
126 ops = find_ioengine(engine);
128 ops = dlopen_ioengine(td, name);
131 log_err("fio: engine %s not loadable\n", name);
136 * Check that the required methods are there.
138 if (check_engine_ops(ops))
141 ret = malloc(sizeof(*ret));
142 memcpy(ret, ops, sizeof(*ret));
148 void close_ioengine(struct thread_data *td)
150 if (td->io_ops->cleanup)
151 td->io_ops->cleanup(td);
153 if (td->io_ops->dlhandle)
154 dlclose(td->io_ops->dlhandle);
160 int td_io_prep(struct thread_data *td, struct io_u *io_u)
162 if (td->io_ops->prep && td->io_ops->prep(td, io_u))
168 int td_io_getevents(struct thread_data *td, int min, int max,
171 return td->io_ops->getevents(td, min, max, t);
174 int td_io_queue(struct thread_data *td, struct io_u *io_u)
176 fio_gettime(&io_u->issue_time, NULL);
178 return td->io_ops->queue(td, io_u);
181 int td_io_init(struct thread_data *td)
183 if (td->io_ops->init)
184 return td->io_ops->init(td);