Update io engine comments
[fio.git] / engines / sg.c
CommitLineData
2866c82d 1/*
da751ca9
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2 * sg engine
3 *
4 * IO engine that uses the Linux SG v3 interface to talk to SCSI devices
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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>
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13
14#include "../fio.h"
15#include "../os.h"
2866c82d 16
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17#ifdef FIO_HAVE_SGIO
18
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19struct sgio_cmd {
20 unsigned char cdb[10];
21 int nr;
22};
23
24struct sgio_data {
25 struct sgio_cmd *cmds;
26 struct io_u **events;
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27 struct pollfd *pfds;
28 int *fd_flags;
29 void *sgbuf;
2866c82d 30 unsigned int bs;
b5af8293 31 int type_checked;
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32};
33
34static void sgio_hdr_init(struct sgio_data *sd, struct sg_io_hdr *hdr,
35 struct io_u *io_u, int fs)
36{
37 struct sgio_cmd *sc = &sd->cmds[io_u->index];
38
39 memset(hdr, 0, sizeof(*hdr));
40 memset(sc->cdb, 0, sizeof(sc->cdb));
41
42 hdr->interface_id = 'S';
43 hdr->cmdp = sc->cdb;
44 hdr->cmd_len = sizeof(sc->cdb);
45 hdr->pack_id = io_u->index;
46 hdr->usr_ptr = io_u;
47
48 if (fs) {
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49 hdr->dxferp = io_u->xfer_buf;
50 hdr->dxfer_len = io_u->xfer_buflen;
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51 }
52}
53
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54static int pollin_events(struct pollfd *pfds, int fds)
55{
56 int i;
57
58 for (i = 0; i < fds; i++)
59 if (pfds[i].revents & POLLIN)
60 return 1;
61
62 return 0;
63}
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64
65static int fio_sgio_getevents(struct thread_data *td, int min, int max,
66 struct timespec fio_unused *t)
67{
adee86c5
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68 /*
69 * normally hard coding &td->files[0] is a bug that needs to be fixed,
70 * but it's ok here as all files should point to the same device.
71 */
53cdc686 72 struct fio_file *f = &td->files[0];
2866c82d 73 struct sgio_data *sd = td->io_ops->data;
af52b345 74 int left = max, ret, r = 0;
dc0deca2 75 void *buf = sd->sgbuf;
af52b345 76 unsigned int i, events;
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77
78 /*
adee86c5 79 * Fill in the file descriptors
2866c82d 80 */
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81 for_each_file(td, f, i) {
82 /*
83 * don't block for min events == 0
84 */
85 if (!min) {
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86 sd->fd_flags[i] = fcntl(f->fd, F_GETFL);
87 fcntl(f->fd, F_SETFL, sd->fd_flags[i] | O_NONBLOCK);
adee86c5 88 }
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89 sd->pfds[i].fd = f->fd;
90 sd->pfds[i].events = POLLIN;
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91 }
92
93 while (left) {
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94 void *p;
95
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96 do {
97 if (!min)
98 break;
adee86c5 99
dc0deca2 100 ret = poll(sd->pfds, td->nr_files, -1);
adee86c5 101 if (ret < 0) {
adee86c5 102 if (!r)
22819ec2 103 r = -errno;
e1161c32 104 td_verror(td, errno, "poll");
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105 break;
106 } else if (!ret)
107 continue;
108
dc0deca2 109 if (pollin_events(sd->pfds, td->nr_files))
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110 break;
111 } while (1);
112
adee86c5 113 if (r < 0)
2866c82d 114 break;
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115
116re_read:
117 p = buf;
118 events = 0;
119 for_each_file(td, f, i) {
120 ret = read(f->fd, p, left * sizeof(struct sg_io_hdr));
121 if (ret < 0) {
122 if (errno == EAGAIN)
123 continue;
22819ec2 124 r = -errno;
e1161c32 125 td_verror(td, errno, "read");
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126 break;
127 } else if (ret) {
128 p += ret;
129 events += ret / sizeof(struct sg_io_hdr);
130 }
131 }
132
133 if (r < 0)
2866c82d 134 break;
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135 if (!events) {
136 usleep(1000);
137 goto re_read;
138 }
2866c82d 139
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140 left -= events;
141 r += events;
142
143 for (i = 0; i < events; i++) {
144 struct sg_io_hdr *hdr = (struct sg_io_hdr *) buf + i;
145
146 sd->events[i] = hdr->usr_ptr;
147 }
148 }
149
adee86c5
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150 if (!min) {
151 for_each_file(td, f, i)
dc0deca2 152 fcntl(f->fd, F_SETFL, sd->fd_flags[i]);
adee86c5 153 }
2866c82d 154
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155 return r;
156}
157
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158static int fio_sgio_ioctl_doio(struct thread_data *td,
159 struct fio_file *f, struct io_u *io_u)
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160{
161 struct sgio_data *sd = td->io_ops->data;
162 struct sg_io_hdr *hdr = &io_u->hdr;
36167d82 163 int ret;
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164
165 sd->events[0] = io_u;
166
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167 ret = ioctl(f->fd, SG_IO, hdr);
168 if (ret < 0)
22819ec2 169 return -errno;
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170
171 return FIO_Q_COMPLETED;
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172}
173
7a16dd02 174static int fio_sgio_rw_doio(struct fio_file *f, struct io_u *io_u, int sync)
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175{
176 struct sg_io_hdr *hdr = &io_u->hdr;
177 int ret;
178
53cdc686 179 ret = write(f->fd, hdr, sizeof(*hdr));
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180 if (ret < 0)
181 return errno;
182
183 if (sync) {
53cdc686 184 ret = read(f->fd, hdr, sizeof(*hdr));
2866c82d 185 if (ret < 0)
22819ec2 186 return -errno;
36167d82 187 return FIO_Q_COMPLETED;
2866c82d
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188 }
189
36167d82 190 return FIO_Q_QUEUED;
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191}
192
193static int fio_sgio_doio(struct thread_data *td, struct io_u *io_u, int sync)
194{
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195 struct fio_file *f = io_u->file;
196
af52b345 197 if (f->filetype == FIO_TYPE_BD)
53cdc686 198 return fio_sgio_ioctl_doio(td, f, io_u);
2866c82d 199
7a16dd02 200 return fio_sgio_rw_doio(f, io_u, sync);
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201}
202
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203static int fio_sgio_prep(struct thread_data *td, struct io_u *io_u)
204{
205 struct sg_io_hdr *hdr = &io_u->hdr;
206 struct sgio_data *sd = td->io_ops->data;
207 int nr_blocks, lba;
208
cec6b55d 209 if (io_u->xfer_buflen & (sd->bs - 1)) {
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210 log_err("read/write not sector aligned\n");
211 return EINVAL;
212 }
213
2866c82d 214 if (io_u->ddir == DDIR_READ) {
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215 sgio_hdr_init(sd, hdr, io_u, 1);
216
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217 hdr->dxfer_direction = SG_DXFER_FROM_DEV;
218 hdr->cmdp[0] = 0x28;
87dc1ab1
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219 } else if (io_u->ddir == DDIR_WRITE) {
220 sgio_hdr_init(sd, hdr, io_u, 1);
221
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222 hdr->dxfer_direction = SG_DXFER_TO_DEV;
223 hdr->cmdp[0] = 0x2a;
87dc1ab1
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224 } else {
225 sgio_hdr_init(sd, hdr, io_u, 0);
226
227 hdr->dxfer_direction = SG_DXFER_NONE;
228 hdr->cmdp[0] = 0x35;
229 }
230
231 if (hdr->dxfer_direction != SG_DXFER_NONE) {
cec6b55d 232 nr_blocks = io_u->xfer_buflen / sd->bs;
87dc1ab1 233 lba = io_u->offset / sd->bs;
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234 hdr->cmdp[2] = (unsigned char) ((lba >> 24) & 0xff);
235 hdr->cmdp[3] = (unsigned char) ((lba >> 16) & 0xff);
236 hdr->cmdp[4] = (unsigned char) ((lba >> 8) & 0xff);
237 hdr->cmdp[5] = (unsigned char) (lba & 0xff);
238 hdr->cmdp[7] = (unsigned char) ((nr_blocks >> 8) & 0xff);
239 hdr->cmdp[8] = (unsigned char) (nr_blocks & 0xff);
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240 }
241
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242 return 0;
243}
244
245static int fio_sgio_queue(struct thread_data *td, struct io_u *io_u)
246{
247 struct sg_io_hdr *hdr = &io_u->hdr;
248 int ret;
249
87dc1ab1 250 ret = fio_sgio_doio(td, io_u, io_u->ddir == DDIR_SYNC);
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251
252 if (ret < 0)
253 io_u->error = errno;
254 else if (hdr->status) {
255 io_u->resid = hdr->resid;
256 io_u->error = EIO;
257 }
258
95bcd815 259 if (io_u->error) {
e1161c32 260 td_verror(td, io_u->error, "xfer");
36167d82 261 return FIO_Q_COMPLETED;
95bcd815
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262 }
263
36167d82 264 return ret;
2866c82d
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265}
266
267static struct io_u *fio_sgio_event(struct thread_data *td, int event)
268{
269 struct sgio_data *sd = td->io_ops->data;
270
271 return sd->events[event];
272}
273
274static int fio_sgio_get_bs(struct thread_data *td, unsigned int *bs)
275{
276 struct sgio_data *sd = td->io_ops->data;
277 struct io_u *io_u;
278 struct sg_io_hdr *hdr;
279 unsigned char buf[8];
280 int ret;
281
282 io_u = __get_io_u(td);
6ab9e267 283 io_u->file = &td->files[0];
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284 assert(io_u);
285
286 hdr = &io_u->hdr;
287 sgio_hdr_init(sd, hdr, io_u, 0);
288 memset(buf, 0, sizeof(buf));
289
290 hdr->cmdp[0] = 0x25;
291 hdr->dxfer_direction = SG_DXFER_FROM_DEV;
292 hdr->dxferp = buf;
293 hdr->dxfer_len = sizeof(buf);
294
295 ret = fio_sgio_doio(td, io_u, 1);
296 if (ret) {
297 put_io_u(td, io_u);
298 return ret;
299 }
300
301 *bs = (buf[4] << 24) | (buf[5] << 16) | (buf[6] << 8) | buf[7];
302 put_io_u(td, io_u);
303 return 0;
304}
305
306static void fio_sgio_cleanup(struct thread_data *td)
307{
dc0deca2
JA
308 struct sgio_data *sd = td->io_ops->data;
309
310 if (sd) {
311 free(sd->events);
312 free(sd->cmds);
313 free(sd->fd_flags);
314 free(sd->pfds);
315 free(sd->sgbuf);
316 free(sd);
317
2866c82d
JA
318 td->io_ops->data = NULL;
319 }
320}
321
322static int fio_sgio_init(struct thread_data *td)
323{
324 struct sgio_data *sd;
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325
326 sd = malloc(sizeof(*sd));
cb781c75 327 memset(sd, 0, sizeof(*sd));
2866c82d 328 sd->cmds = malloc(td->iodepth * sizeof(struct sgio_cmd));
cb781c75 329 memset(sd->cmds, 0, td->iodepth * sizeof(struct sgio_cmd));
2866c82d 330 sd->events = malloc(td->iodepth * sizeof(struct io_u *));
cb781c75 331 memset(sd->events, 0, td->iodepth * sizeof(struct io_u *));
dc0deca2
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332 sd->pfds = malloc(sizeof(struct pollfd) * td->nr_files);
333 memset(sd->pfds, 0, sizeof(struct pollfd) * td->nr_files);
334 sd->fd_flags = malloc(sizeof(int) * td->nr_files);
335 memset(sd->fd_flags, 0, sizeof(int) * td->nr_files);
336 sd->sgbuf = malloc(sizeof(struct sg_io_hdr) * td->iodepth);
337 memset(sd->sgbuf, 0, sizeof(struct sg_io_hdr) * td->iodepth);
338
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339 td->io_ops->data = sd;
340
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341 /*
342 * we want to do it, regardless of whether odirect is set or not
343 */
344 td->override_sync = 1;
345 return 0;
346}
347
348static 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
af52b345 353 if (f->filetype == FIO_TYPE_BD) {
53cdc686 354 if (ioctl(f->fd, BLKSSZGET, &bs) < 0) {
e1161c32 355 td_verror(td, errno, "ioctl");
b5af8293 356 return 1;
2866c82d 357 }
af52b345 358 } else if (f->filetype == FIO_TYPE_CHAR) {
b5af8293 359 int version, ret;
2866c82d 360
53cdc686 361 if (ioctl(f->fd, SG_GET_VERSION_NUM, &version) < 0) {
e1161c32 362 td_verror(td, errno, "ioctl");
b5af8293 363 return 1;
2866c82d
JA
364 }
365
366 ret = fio_sgio_get_bs(td, &bs);
367 if (ret)
b5af8293 368 return 1;
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369 } else {
370 log_err("ioengine sgio only works on block devices\n");
b5af8293 371 return 1;
2866c82d
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372 }
373
374 sd->bs = bs;
375
af52b345 376 if (f->filetype == FIO_TYPE_BD) {
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377 td->io_ops->getevents = NULL;
378 td->io_ops->event = NULL;
379 }
2866c82d 380
2866c82d 381 return 0;
b5af8293
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382}
383
384static 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->type_checked && fio_sgio_type_check(td, f)) {
394 generic_close_file(td, f);
395 return 1;
396 }
397
398 return 0;
2866c82d
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399}
400
5f350952 401static struct ioengine_ops ioengine = {
2866c82d
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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,
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410 .open_file = fio_sgio_open,
411 .close_file = generic_close_file,
b2a15192 412 .flags = FIO_SYNCIO | FIO_RAWIO,
2866c82d 413};
34cfcdaf
JA
414
415#else /* FIO_HAVE_SGIO */
416
417/*
418 * When we have a proper configure system in place, we simply wont build
419 * and install this io engine. For now install a crippled version that
420 * just complains and fails to load.
421 */
422static int fio_sgio_init(struct thread_data fio_unused *td)
423{
424 fprintf(stderr, "fio: sgio not available\n");
425 return 1;
426}
427
5f350952 428static struct ioengine_ops ioengine = {
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JA
429 .name = "sgio",
430 .version = FIO_IOOPS_VERSION,
431 .init = fio_sgio_init,
432};
433
434#endif
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435
436static void fio_init fio_sgio_register(void)
437{
438 register_ioengine(&ioengine);
439}
440
441static void fio_exit fio_sgio_unregister(void)
442{
443 unregister_ioengine(&ioengine);
444}