1 /*
2 * sg engine
3 *
4 * IO engine that uses the Linux SG v3 interface to talk to SCSI devices
5 *
6 */
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <unistd.h>
10 #include <errno.h>
11 #include <assert.h>
12 #include <sys/poll.h>
13
14 #include "../fio.h"
15
16 #ifdef FIO_HAVE_SGIO
17
18 struct sgio_cmd {
19 unsigned char cdb[10];
20 int nr;
21 };
22
23 struct sgio_data {
24 struct sgio_cmd *cmds;
25 struct io_u **events;
26 struct pollfd *pfds;
27 int *fd_flags;
28 void *sgbuf;
29 unsigned int bs;
30 int type_checked;
31 };
32
sgio_hdr_init(struct sgio_data * sd,struct sg_io_hdr * hdr,struct io_u * io_u,int fs)33 static void sgio_hdr_init(struct sgio_data *sd, struct sg_io_hdr *hdr,
34 struct io_u *io_u, int fs)
35 {
36 struct sgio_cmd *sc = &sd->cmds[io_u->index];
37
38 memset(hdr, 0, sizeof(*hdr));
39 memset(sc->cdb, 0, sizeof(sc->cdb));
40
41 hdr->interface_id = 'S';
42 hdr->cmdp = sc->cdb;
43 hdr->cmd_len = sizeof(sc->cdb);
44 hdr->pack_id = io_u->index;
45 hdr->usr_ptr = io_u;
46
47 if (fs) {
48 hdr->dxferp = io_u->xfer_buf;
49 hdr->dxfer_len = io_u->xfer_buflen;
50 }
51 }
52
pollin_events(struct pollfd * pfds,int fds)53 static int pollin_events(struct pollfd *pfds, int fds)
54 {
55 int i;
56
57 for (i = 0; i < fds; i++)
58 if (pfds[i].revents & POLLIN)
59 return 1;
60
61 return 0;
62 }
63
fio_sgio_getevents(struct thread_data * td,unsigned int min,unsigned int max,struct timespec fio_unused * t)64 static int fio_sgio_getevents(struct thread_data *td, unsigned int min,
65 unsigned int max, struct timespec fio_unused *t)
66 {
67 struct sgio_data *sd = td->io_ops->data;
68 int left = max, ret, r = 0;
69 void *buf = sd->sgbuf;
70 unsigned int i, events;
71 struct fio_file *f;
72
73 /*
74 * Fill in the file descriptors
75 */
76 for_each_file(td, f, i) {
77 /*
78 * don't block for min events == 0
79 */
80 if (!min)
81 sd->fd_flags[i] = fio_set_fd_nonblocking(f->fd, "sg");
82 else
83 sd->fd_flags[i] = -1;
84
85 sd->pfds[i].fd = f->fd;
86 sd->pfds[i].events = POLLIN;
87 }
88
89 while (left) {
90 void *p;
91
92 do {
93 if (!min)
94 break;
95
96 ret = poll(sd->pfds, td->o.nr_files, -1);
97 if (ret < 0) {
98 if (!r)
99 r = -errno;
100 td_verror(td, errno, "poll");
101 break;
102 } else if (!ret)
103 continue;
104
105 if (pollin_events(sd->pfds, td->o.nr_files))
106 break;
107 } while (1);
108
109 if (r < 0)
110 break;
111
112 re_read:
113 p = buf;
114 events = 0;
115 for_each_file(td, f, i) {
116 ret = read(f->fd, p, left * sizeof(struct sg_io_hdr));
117 if (ret < 0) {
118 if (errno == EAGAIN)
119 continue;
120 r = -errno;
121 td_verror(td, errno, "read");
122 break;
123 } else if (ret) {
124 p += ret;
125 events += ret / sizeof(struct sg_io_hdr);
126 }
127 }
128
129 if (r < 0)
130 break;
131 if (!events) {
132 usleep(1000);
133 goto re_read;
134 }
135
136 left -= events;
137 r += events;
138
139 for (i = 0; i < events; i++) {
140 struct sg_io_hdr *hdr = (struct sg_io_hdr *) buf + i;
141
142 sd->events[i] = hdr->usr_ptr;
143 }
144 }
145
146 if (!min) {
147 for_each_file(td, f, i) {
148 if (sd->fd_flags[i] == -1)
149 continue;
150
151 if (fcntl(f->fd, F_SETFL, sd->fd_flags[i]) < 0)
152 log_err("fio: sg failed to restore fcntl flags: %s\n", strerror(errno));
153 }
154 }
155
156 return r;
157 }
158
fio_sgio_ioctl_doio(struct thread_data * td,struct fio_file * f,struct io_u * io_u)159 static int fio_sgio_ioctl_doio(struct thread_data *td,
160 struct fio_file *f, struct io_u *io_u)
161 {
162 struct sgio_data *sd = td->io_ops->data;
163 struct sg_io_hdr *hdr = &io_u->hdr;
164 int ret;
165
166 sd->events[0] = io_u;
167
168 ret = ioctl(f->fd, SG_IO, hdr);
169 if (ret < 0)
170 return ret;
171
172 return FIO_Q_COMPLETED;
173 }
174
fio_sgio_rw_doio(struct fio_file * f,struct io_u * io_u,int do_sync)175 static int fio_sgio_rw_doio(struct fio_file *f, struct io_u *io_u, int do_sync)
176 {
177 struct sg_io_hdr *hdr = &io_u->hdr;
178 int ret;
179
180 ret = write(f->fd, hdr, sizeof(*hdr));
181 if (ret < 0)
182 return ret;
183
184 if (do_sync) {
185 ret = read(f->fd, hdr, sizeof(*hdr));
186 if (ret < 0)
187 return ret;
188 return FIO_Q_COMPLETED;
189 }
190
191 return FIO_Q_QUEUED;
192 }
193
fio_sgio_doio(struct thread_data * td,struct io_u * io_u,int do_sync)194 static int fio_sgio_doio(struct thread_data *td, struct io_u *io_u, int do_sync)
195 {
196 struct fio_file *f = io_u->file;
197
198 if (f->filetype == FIO_TYPE_BD)
199 return fio_sgio_ioctl_doio(td, f, io_u);
200
201 return fio_sgio_rw_doio(f, io_u, do_sync);
202 }
203
fio_sgio_prep(struct thread_data * td,struct io_u * io_u)204 static int fio_sgio_prep(struct thread_data *td, struct io_u *io_u)
205 {
206 struct sg_io_hdr *hdr = &io_u->hdr;
207 struct sgio_data *sd = td->io_ops->data;
208 int nr_blocks, lba;
209
210 if (io_u->xfer_buflen & (sd->bs - 1)) {
211 log_err("read/write not sector aligned\n");
212 return EINVAL;
213 }
214
215 if (io_u->ddir == DDIR_READ) {
216 sgio_hdr_init(sd, hdr, io_u, 1);
217
218 hdr->dxfer_direction = SG_DXFER_FROM_DEV;
219 hdr->cmdp[0] = 0x28;
220 } else if (io_u->ddir == DDIR_WRITE) {
221 sgio_hdr_init(sd, hdr, io_u, 1);
222
223 hdr->dxfer_direction = SG_DXFER_TO_DEV;
224 hdr->cmdp[0] = 0x2a;
225 } else {
226 sgio_hdr_init(sd, hdr, io_u, 0);
227
228 hdr->dxfer_direction = SG_DXFER_NONE;
229 hdr->cmdp[0] = 0x35;
230 }
231
232 if (hdr->dxfer_direction != SG_DXFER_NONE) {
233 nr_blocks = io_u->xfer_buflen / sd->bs;
234 lba = io_u->offset / sd->bs;
235 hdr->cmdp[2] = (unsigned char) ((lba >> 24) & 0xff);
236 hdr->cmdp[3] = (unsigned char) ((lba >> 16) & 0xff);
237 hdr->cmdp[4] = (unsigned char) ((lba >> 8) & 0xff);
238 hdr->cmdp[5] = (unsigned char) (lba & 0xff);
239 hdr->cmdp[7] = (unsigned char) ((nr_blocks >> 8) & 0xff);
240 hdr->cmdp[8] = (unsigned char) (nr_blocks & 0xff);
241 }
242
243 return 0;
244 }
245
fio_sgio_queue(struct thread_data * td,struct io_u * io_u)246 static int fio_sgio_queue(struct thread_data *td, struct io_u *io_u)
247 {
248 struct sg_io_hdr *hdr = &io_u->hdr;
249 int ret, do_sync = 0;
250
251 fio_ro_check(td, io_u);
252
253 if (td->o.sync_io || td->o.odirect || ddir_sync(io_u->ddir))
254 do_sync = 1;
255
256 ret = fio_sgio_doio(td, io_u, do_sync);
257
258 if (ret < 0)
259 io_u->error = errno;
260 else if (hdr->status) {
261 io_u->resid = hdr->resid;
262 io_u->error = EIO;
263 }
264
265 if (io_u->error) {
266 td_verror(td, io_u->error, "xfer");
267 return FIO_Q_COMPLETED;
268 }
269
270 return ret;
271 }
272
fio_sgio_event(struct thread_data * td,int event)273 static struct io_u *fio_sgio_event(struct thread_data *td, int event)
274 {
275 struct sgio_data *sd = td->io_ops->data;
276
277 return sd->events[event];
278 }
279
fio_sgio_get_bs(struct thread_data * td,unsigned int * bs)280 static int fio_sgio_get_bs(struct thread_data *td, unsigned int *bs)
281 {
282 struct sgio_data *sd = td->io_ops->data;
283 struct io_u io_u;
284 struct sg_io_hdr *hdr;
285 unsigned char buf[8];
286 int ret;
287
288 memset(&io_u, 0, sizeof(io_u));
289 io_u.file = td->files[0];
290
291 hdr = &io_u.hdr;
292 sgio_hdr_init(sd, hdr, &io_u, 0);
293 memset(buf, 0, sizeof(buf));
294
295 hdr->cmdp[0] = 0x25;
296 hdr->dxfer_direction = SG_DXFER_FROM_DEV;
297 hdr->dxferp = buf;
298 hdr->dxfer_len = sizeof(buf);
299
300 ret = fio_sgio_doio(td, &io_u, 1);
301 if (ret)
302 return ret;
303
304 *bs = (buf[4] << 24) | (buf[5] << 16) | (buf[6] << 8) | buf[7];
305 return 0;
306 }
307
fio_sgio_cleanup(struct thread_data * td)308 static void fio_sgio_cleanup(struct thread_data *td)
309 {
310 struct sgio_data *sd = td->io_ops->data;
311
312 if (sd) {
313 free(sd->events);
314 free(sd->cmds);
315 free(sd->fd_flags);
316 free(sd->pfds);
317 free(sd->sgbuf);
318 free(sd);
319 }
320 }
321
fio_sgio_init(struct thread_data * td)322 static int fio_sgio_init(struct thread_data *td)
323 {
324 struct sgio_data *sd;
325
326 sd = malloc(sizeof(*sd));
327 memset(sd, 0, sizeof(*sd));
328 sd->cmds = malloc(td->o.iodepth * sizeof(struct sgio_cmd));
329 memset(sd->cmds, 0, td->o.iodepth * sizeof(struct sgio_cmd));
330 sd->events = malloc(td->o.iodepth * sizeof(struct io_u *));
331 memset(sd->events, 0, td->o.iodepth * sizeof(struct io_u *));
332 sd->pfds = malloc(sizeof(struct pollfd) * td->o.nr_files);
333 memset(sd->pfds, 0, sizeof(struct pollfd) * td->o.nr_files);
334 sd->fd_flags = malloc(sizeof(int) * td->o.nr_files);
335 memset(sd->fd_flags, 0, sizeof(int) * td->o.nr_files);
336 sd->sgbuf = malloc(sizeof(struct sg_io_hdr) * td->o.iodepth);
337 memset(sd->sgbuf, 0, sizeof(struct sg_io_hdr) * td->o.iodepth);
338
339 td->io_ops->data = sd;
340
341 /*
342 * we want to do it, regardless of whether odirect is set or not
343 */
344 td->o.override_sync = 1;
345 return 0;
346 }
347
fio_sgio_type_check(struct thread_data * td,struct fio_file * f)348 static int fio_sgio_type_check(struct thread_data *td, struct fio_file *f)
349 {
350 struct sgio_data *sd = td->io_ops->data;
351 unsigned int bs;
352
353 if (f->filetype == FIO_TYPE_BD) {
354 if (ioctl(f->fd, BLKSSZGET, &bs) < 0) {
355 td_verror(td, errno, "ioctl");
356 return 1;
357 }
358 } else if (f->filetype == FIO_TYPE_CHAR) {
359 int version, ret;
360
361 if (ioctl(f->fd, SG_GET_VERSION_NUM, &version) < 0) {
362 td_verror(td, errno, "ioctl");
363 return 1;
364 }
365
366 ret = fio_sgio_get_bs(td, &bs);
367 if (ret)
368 return 1;
369 } else {
370 log_err("ioengine sg only works on block devices\n");
371 return 1;
372 }
373
374 sd->bs = bs;
375
376 if (f->filetype == FIO_TYPE_BD) {
377 td->io_ops->getevents = NULL;
378 td->io_ops->event = NULL;
379 }
380
381 return 0;
382 }
383
fio_sgio_open(struct thread_data * td,struct fio_file * f)384 static int fio_sgio_open(struct thread_data *td, struct fio_file *f)
385 {
386 struct sgio_data *sd = td->io_ops->data;
387 int ret;
388
389 ret = generic_open_file(td, f);
390 if (ret)
391 return ret;
392
393 if (sd && !sd->type_checked && fio_sgio_type_check(td, f)) {
394 ret = generic_close_file(td, f);
395 return 1;
396 }
397
398 return 0;
399 }
400
401 static struct ioengine_ops ioengine = {
402 .name = "sg",
403 .version = FIO_IOOPS_VERSION,
404 .init = fio_sgio_init,
405 .prep = fio_sgio_prep,
406 .queue = fio_sgio_queue,
407 .getevents = fio_sgio_getevents,
408 .event = fio_sgio_event,
409 .cleanup = fio_sgio_cleanup,
410 .open_file = fio_sgio_open,
411 .close_file = generic_close_file,
412 .get_file_size = generic_get_file_size,
413 .flags = FIO_SYNCIO | FIO_RAWIO,
414 };
415
416 #else /* FIO_HAVE_SGIO */
417
418 /*
419 * When we have a proper configure system in place, we simply wont build
420 * and install this io engine. For now install a crippled version that
421 * just complains and fails to load.
422 */
fio_sgio_init(struct thread_data fio_unused * td)423 static int fio_sgio_init(struct thread_data fio_unused *td)
424 {
425 log_err("fio: ioengine sg not available\n");
426 return 1;
427 }
428
429 static struct ioengine_ops ioengine = {
430 .name = "sg",
431 .version = FIO_IOOPS_VERSION,
432 .init = fio_sgio_init,
433 };
434
435 #endif
436
fio_sgio_register(void)437 static void fio_init fio_sgio_register(void)
438 {
439 register_ioengine(&ioengine);
440 }
441
fio_sgio_unregister(void)442 static void fio_exit fio_sgio_unregister(void)
443 {
444 unregister_ioengine(&ioengine);
445 }
446