1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
8 #include <sys/socket.h>
10 #include <sys/types.h>
14 #include <rte_common.h>
20 #define RTE_LOGTYPE_VHOST_FDMAN RTE_LOGTYPE_USER1
22 #define FDPOLLERR (POLLERR | POLLHUP | POLLNVAL)
25 get_last_valid_idx(struct fdset *pfdset, int last_valid_idx)
29 for (i = last_valid_idx; i >= 0 && pfdset->fd[i].fd == -1; i--)
36 fdset_move(struct fdset *pfdset, int dst, int src)
38 pfdset->fd[dst] = pfdset->fd[src];
39 pfdset->rwfds[dst] = pfdset->rwfds[src];
43 fdset_shrink_nolock(struct fdset *pfdset)
46 int last_valid_idx = get_last_valid_idx(pfdset, pfdset->num - 1);
48 for (i = 0; i < last_valid_idx; i++) {
49 if (pfdset->fd[i].fd != -1)
52 fdset_move(pfdset, i, last_valid_idx);
53 last_valid_idx = get_last_valid_idx(pfdset, last_valid_idx - 1);
55 pfdset->num = last_valid_idx + 1;
59 * Find deleted fd entries and remove them
62 fdset_shrink(struct fdset *pfdset)
64 pthread_mutex_lock(&pfdset->fd_mutex);
65 fdset_shrink_nolock(pfdset);
66 pthread_mutex_unlock(&pfdset->fd_mutex);
70 * Returns the index in the fdset for a given fd.
72 * index for the fd, or -1 if fd isn't in the fdset.
75 fdset_find_fd(struct fdset *pfdset, int fd)
79 for (i = 0; i < pfdset->num && pfdset->fd[i].fd != fd; i++)
82 return i == pfdset->num ? -1 : i;
86 fdset_add_fd(struct fdset *pfdset, int idx, int fd,
87 fd_cb rcb, fd_cb wcb, void *dat)
89 struct fdentry *pfdentry = &pfdset->fd[idx];
90 struct pollfd *pfd = &pfdset->rwfds[idx];
98 pfd->events = rcb ? POLLIN : 0;
99 pfd->events |= wcb ? POLLOUT : 0;
104 fdset_init(struct fdset *pfdset)
111 for (i = 0; i < MAX_FDS; i++) {
112 pfdset->fd[i].fd = -1;
113 pfdset->fd[i].dat = NULL;
119 * Register the fd in the fdset with read/write handler and context.
122 fdset_add(struct fdset *pfdset, int fd, fd_cb rcb, fd_cb wcb, void *dat)
126 if (pfdset == NULL || fd == -1)
129 pthread_mutex_lock(&pfdset->fd_mutex);
130 i = pfdset->num < MAX_FDS ? pfdset->num++ : -1;
132 fdset_shrink_nolock(pfdset);
133 i = pfdset->num < MAX_FDS ? pfdset->num++ : -1;
135 pthread_mutex_unlock(&pfdset->fd_mutex);
140 fdset_add_fd(pfdset, i, fd, rcb, wcb, dat);
141 pthread_mutex_unlock(&pfdset->fd_mutex);
147 * Unregister the fd from the fdset.
148 * Returns context of a given fd or NULL.
151 fdset_del(struct fdset *pfdset, int fd)
156 if (pfdset == NULL || fd == -1)
160 pthread_mutex_lock(&pfdset->fd_mutex);
162 i = fdset_find_fd(pfdset, fd);
163 if (i != -1 && pfdset->fd[i].busy == 0) {
164 /* busy indicates r/wcb is executing! */
165 dat = pfdset->fd[i].dat;
166 pfdset->fd[i].fd = -1;
167 pfdset->fd[i].rcb = pfdset->fd[i].wcb = NULL;
168 pfdset->fd[i].dat = NULL;
171 pthread_mutex_unlock(&pfdset->fd_mutex);
179 * This functions runs in infinite blocking loop until there is no fd in
180 * pfdset. It calls corresponding r/w handler if there is event on the fd.
182 * Before the callback is called, we set the flag to busy status; If other
183 * thread(now rte_vhost_driver_unregister) calls fdset_del concurrently, it
184 * will wait until the flag is reset to zero(which indicates the callback is
185 * finished), then it could free the context after fdset_del.
188 fdset_event_dispatch(void *arg)
192 struct fdentry *pfdentry;
196 int remove1, remove2;
198 struct fdset *pfdset = arg;
207 * When poll is blocked, other threads might unregister
208 * listenfds from and register new listenfds into fdset.
209 * When poll returns, the entries for listenfds in the fdset
210 * might have been updated. It is ok if there is unwanted call
213 pthread_mutex_lock(&pfdset->fd_mutex);
214 numfds = pfdset->num;
215 pthread_mutex_unlock(&pfdset->fd_mutex);
217 val = poll(pfdset->rwfds, numfds, 1000 /* millisecs */);
222 for (i = 0; i < numfds; i++) {
223 pthread_mutex_lock(&pfdset->fd_mutex);
225 pfdentry = &pfdset->fd[i];
227 pfd = &pfdset->rwfds[i];
231 pthread_mutex_unlock(&pfdset->fd_mutex);
236 pthread_mutex_unlock(&pfdset->fd_mutex);
240 remove1 = remove2 = 0;
247 pthread_mutex_unlock(&pfdset->fd_mutex);
249 if (rcb && pfd->revents & (POLLIN | FDPOLLERR))
250 rcb(fd, dat, &remove1);
251 if (wcb && pfd->revents & (POLLOUT | FDPOLLERR))
252 wcb(fd, dat, &remove2);
255 * fdset_del needs to check busy flag.
256 * We don't allow fdset_del to be called in callback
260 * When we are to clean up the fd from fdset,
261 * because the fd is closed in the cb,
262 * the old fd val could be reused by when creates new
263 * listen fd in another thread, we couldn't call
266 if (remove1 || remove2) {
273 fdset_shrink(pfdset);
280 fdset_pipe_read_cb(int readfd, void *dat __rte_unused,
281 int *remove __rte_unused)
284 int r = read(readfd, charbuf, sizeof(charbuf));
286 * Just an optimization, we don't care if read() failed
287 * so ignore explicitly its return value to make the
294 fdset_pipe_uninit(struct fdset *fdset)
296 fdset_del(fdset, fdset->u.readfd);
297 close(fdset->u.readfd);
298 close(fdset->u.writefd);
302 fdset_pipe_init(struct fdset *fdset)
306 if (pipe(fdset->u.pipefd) < 0) {
307 RTE_LOG(ERR, VHOST_FDMAN,
308 "failed to create pipe for vhost fdset\n");
312 ret = fdset_add(fdset, fdset->u.readfd,
313 fdset_pipe_read_cb, NULL, NULL);
316 RTE_LOG(ERR, VHOST_FDMAN,
317 "failed to add pipe readfd %d into vhost server fdset\n",
320 fdset_pipe_uninit(fdset);
328 fdset_pipe_notify(struct fdset *fdset)
330 int r = write(fdset->u.writefd, "1", 1);
332 * Just an optimization, we don't care if write() failed
333 * so ignore explicitly its return value to make the