1 | /*$NetBSD: dm_target_stripe.c,v 1.21 2014/08/19 14:43:28 christos Exp $*/ |
2 | |
3 | /* |
4 | * Copyright (c) 2009 The NetBSD Foundation, Inc. |
5 | * All rights reserved. |
6 | * |
7 | * This code is derived from software contributed to The NetBSD Foundation |
8 | * by Adam Hamsik. |
9 | * |
10 | * Redistribution and use in source and binary forms, with or without |
11 | * modification, are permitted provided that the following conditions |
12 | * are met: |
13 | * 1. Redistributions of source code must retain the above copyright |
14 | * notice, this list of conditions and the following disclaimer. |
15 | * 2. Redistributions in binary form must reproduce the above copyright |
16 | * notice, this list of conditions and the following disclaimer in the |
17 | * documentation and/or other materials provided with the distribution. |
18 | * |
19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
29 | * POSSIBILITY OF SUCH DAMAGE. |
30 | */ |
31 | |
32 | /* |
33 | * This file implements initial version of device-mapper stripe target. |
34 | */ |
35 | #include <sys/types.h> |
36 | #include <sys/param.h> |
37 | |
38 | #include <sys/buf.h> |
39 | #include <sys/kmem.h> |
40 | #include <sys/vnode.h> |
41 | #include <sys/lwp.h> |
42 | |
43 | #include "dm.h" |
44 | |
45 | #ifdef DM_TARGET_MODULE |
46 | /* |
47 | * Every target can be compiled directly to dm driver or as a |
48 | * separate module this part of target is used for loading targets |
49 | * to dm driver. |
50 | * Target can be unloaded from kernel only if there are no users of |
51 | * it e.g. there are no devices which uses that target. |
52 | */ |
53 | #include <sys/kernel.h> |
54 | #include <sys/module.h> |
55 | |
56 | MODULE(MODULE_CLASS_MISC, dm_target_stripe, NULL); |
57 | |
58 | static int |
59 | dm_target_stripe_modcmd(modcmd_t cmd, void *arg) |
60 | { |
61 | dm_target_t *dmt; |
62 | int r; |
63 | dmt = NULL; |
64 | |
65 | switch (cmd) { |
66 | case MODULE_CMD_INIT: |
67 | if ((dmt = dm_target_lookup("stripe" )) != NULL) { |
68 | dm_target_unbusy(dmt); |
69 | return EEXIST; |
70 | } |
71 | dmt = dm_target_alloc("stripe" ); |
72 | |
73 | dmt->version[0] = 1; |
74 | dmt->version[1] = 0; |
75 | dmt->version[2] = 0; |
76 | strlcpy(dmt->name, "stripe" , DM_MAX_TYPE_NAME); |
77 | dmt->init = &dm_target_stripe_init; |
78 | dmt->status = &dm_target_stripe_status; |
79 | dmt->strategy = &dm_target_stripe_strategy; |
80 | dmt->sync = &dm_target_stripe_sync; |
81 | dmt->deps = &dm_target_stripe_deps; |
82 | dmt->destroy = &dm_target_stripe_destroy; |
83 | dmt->upcall = &dm_target_stripe_upcall; |
84 | dmt->secsize = &dm_target_stripe_secsize; |
85 | |
86 | r = dm_target_insert(dmt); |
87 | |
88 | break; |
89 | |
90 | case MODULE_CMD_FINI: |
91 | r = dm_target_rem("stripe" ); |
92 | break; |
93 | |
94 | case MODULE_CMD_STAT: |
95 | return ENOTTY; |
96 | |
97 | default: |
98 | return ENOTTY; |
99 | } |
100 | |
101 | return r; |
102 | } |
103 | #endif |
104 | |
105 | static void |
106 | dm_target_stripe_fini(dm_target_stripe_config_t *tsc) |
107 | { |
108 | dm_target_linear_config_t *tlc; |
109 | |
110 | if (tsc == NULL) |
111 | return; |
112 | |
113 | while ((tlc = TAILQ_FIRST(&tsc->stripe_devs)) != NULL) { |
114 | TAILQ_REMOVE(&tsc->stripe_devs, tlc, entries); |
115 | dm_pdev_decr(tlc->pdev); |
116 | kmem_free(tlc, sizeof(*tlc)); |
117 | } |
118 | |
119 | kmem_free(tsc, sizeof(*tsc)); |
120 | } |
121 | |
122 | /* |
123 | * Init function called from dm_table_load_ioctl. |
124 | * DM_STRIPE_DEV_OFFSET should always hold the index of the first device-offset |
125 | * pair in the parameters. |
126 | * Example line sent to dm from lvm tools when using striped target. |
127 | * start length striped #stripes chunk_size device1 offset1 ... deviceN offsetN |
128 | * 0 65536 striped 2 512 /dev/hda 0 /dev/hdb 0 |
129 | */ |
130 | int |
131 | dm_target_stripe_init(dm_dev_t * dmv, void **target_config, char *params) |
132 | { |
133 | dm_target_linear_config_t *tlc; |
134 | dm_target_stripe_config_t *tsc; |
135 | size_t len; |
136 | char **ap, *argv[10]; |
137 | int strpc, strpi; |
138 | |
139 | if (params == NULL) |
140 | return EINVAL; |
141 | |
142 | len = strlen(params) + 1; |
143 | |
144 | /* |
145 | * Parse a string, containing tokens delimited by white space, |
146 | * into an argument vector |
147 | */ |
148 | for (ap = argv; ap <= &argv[9] && |
149 | (*ap = strsep(¶ms, " \t" )) != NULL;) { |
150 | if (**ap != '\0') |
151 | ap++; |
152 | } |
153 | |
154 | printf("Stripe target init function called!!\n" ); |
155 | |
156 | printf("Stripe target chunk size %s number of stripes %s\n" , |
157 | argv[1], argv[0]); |
158 | |
159 | if ((tsc = kmem_alloc(sizeof(*tsc), KM_NOSLEEP)) == NULL) |
160 | return ENOMEM; |
161 | |
162 | /* Initialize linked list for striping devices */ |
163 | TAILQ_INIT(&tsc->stripe_devs); |
164 | |
165 | /* Save length of param string */ |
166 | tsc->params_len = len; |
167 | tsc->stripe_chunksize = atoi(argv[1]); |
168 | tsc->stripe_num = (uint8_t) atoi(argv[0]); |
169 | |
170 | strpc = DM_STRIPE_DEV_OFFSET + (tsc->stripe_num * 2); |
171 | for (strpi = DM_STRIPE_DEV_OFFSET; strpi < strpc; strpi += 2) { |
172 | printf("Stripe target device name %s -- offset %s\n" , |
173 | argv[strpi], argv[strpi+1]); |
174 | |
175 | tlc = kmem_alloc(sizeof(*tlc), KM_NOSLEEP); |
176 | if ((tlc->pdev = dm_pdev_insert(argv[strpi])) == NULL) { |
177 | kmem_free(tlc, sizeof(*tlc)); |
178 | dm_target_stripe_fini(tsc); |
179 | return ENOENT; |
180 | } |
181 | tlc->offset = atoi(argv[strpi+1]); |
182 | |
183 | /* Insert striping device to linked list. */ |
184 | TAILQ_INSERT_TAIL(&tsc->stripe_devs, tlc, entries); |
185 | } |
186 | |
187 | *target_config = tsc; |
188 | |
189 | dmv->dev_type = DM_STRIPE_DEV; |
190 | |
191 | return 0; |
192 | } |
193 | /* Status routine called to get params string. */ |
194 | char * |
195 | dm_target_stripe_status(void *target_config) |
196 | { |
197 | dm_target_linear_config_t *tlc; |
198 | dm_target_stripe_config_t *tsc; |
199 | char *params, *tmp; |
200 | |
201 | tsc = target_config; |
202 | |
203 | if ((params = kmem_alloc(DM_MAX_PARAMS_SIZE, KM_SLEEP)) == NULL) |
204 | return NULL; |
205 | |
206 | if ((tmp = kmem_alloc(DM_MAX_PARAMS_SIZE, KM_SLEEP)) == NULL) { |
207 | kmem_free(params, DM_MAX_PARAMS_SIZE); |
208 | return NULL; |
209 | } |
210 | |
211 | snprintf(params, DM_MAX_PARAMS_SIZE, "%d %" PRIu64, |
212 | tsc->stripe_num, tsc->stripe_chunksize); |
213 | |
214 | TAILQ_FOREACH(tlc, &tsc->stripe_devs, entries) { |
215 | snprintf(tmp, DM_MAX_PARAMS_SIZE, " %s %" PRIu64, |
216 | tlc->pdev->name, tlc->offset); |
217 | strcat(params, tmp); |
218 | } |
219 | |
220 | kmem_free(tmp, DM_MAX_PARAMS_SIZE); |
221 | |
222 | return params; |
223 | } |
224 | /* Strategy routine called from dm_strategy. */ |
225 | int |
226 | dm_target_stripe_strategy(dm_table_entry_t * table_en, struct buf * bp) |
227 | { |
228 | dm_target_linear_config_t *tlc; |
229 | dm_target_stripe_config_t *tsc; |
230 | struct buf *nestbuf; |
231 | uint64_t blkno, blkoff; |
232 | uint64_t stripe, stripe_blknr; |
233 | uint32_t stripe_off, stripe_rest, num_blks, issue_blks; |
234 | int i, stripe_devnr; |
235 | |
236 | tsc = table_en->target_config; |
237 | if (tsc == NULL) |
238 | return 0; |
239 | |
240 | /* printf("Stripe target read function called %" PRIu64 "!!\n", |
241 | tlc->offset);*/ |
242 | |
243 | /* calculate extent of request */ |
244 | KASSERT(bp->b_resid % DEV_BSIZE == 0); |
245 | |
246 | blkno = bp->b_blkno; |
247 | blkoff = 0; |
248 | num_blks = bp->b_resid / DEV_BSIZE; |
249 | for (;;) { |
250 | /* blockno to strip piece nr */ |
251 | stripe = blkno / tsc->stripe_chunksize; |
252 | stripe_off = blkno % tsc->stripe_chunksize; |
253 | |
254 | /* where we are inside the strip */ |
255 | stripe_devnr = stripe % tsc->stripe_num; |
256 | stripe_blknr = stripe / tsc->stripe_num; |
257 | |
258 | /* how much is left before we hit a boundary */ |
259 | stripe_rest = tsc->stripe_chunksize - stripe_off; |
260 | |
261 | /* issue this piece on stripe `stripe' */ |
262 | issue_blks = MIN(stripe_rest, num_blks); |
263 | nestbuf = getiobuf(NULL, true); |
264 | |
265 | nestiobuf_setup(bp, nestbuf, blkoff, issue_blks * DEV_BSIZE); |
266 | nestbuf->b_blkno = stripe_blknr * tsc->stripe_chunksize + stripe_off; |
267 | |
268 | tlc = TAILQ_FIRST(&tsc->stripe_devs); |
269 | for (i = 0; i < stripe_devnr && tlc != NULL; i++) |
270 | tlc = TAILQ_NEXT(tlc, entries); |
271 | |
272 | /* by this point we should have an tlc */ |
273 | KASSERT(tlc != NULL); |
274 | |
275 | nestbuf->b_blkno += tlc->offset; |
276 | |
277 | VOP_STRATEGY(tlc->pdev->pdev_vnode, nestbuf); |
278 | |
279 | blkno += issue_blks; |
280 | blkoff += issue_blks * DEV_BSIZE; |
281 | num_blks -= issue_blks; |
282 | |
283 | if (num_blks <= 0) |
284 | break; |
285 | } |
286 | |
287 | return 0; |
288 | } |
289 | /* Sync underlying disk caches. */ |
290 | int |
291 | dm_target_stripe_sync(dm_table_entry_t * table_en) |
292 | { |
293 | int cmd, err; |
294 | dm_target_stripe_config_t *tsc; |
295 | dm_target_linear_config_t *tlc; |
296 | |
297 | tsc = table_en->target_config; |
298 | |
299 | err = 0; |
300 | cmd = 1; |
301 | |
302 | TAILQ_FOREACH(tlc, &tsc->stripe_devs, entries) { |
303 | if ((err = VOP_IOCTL(tlc->pdev->pdev_vnode, DIOCCACHESYNC, |
304 | &cmd, FREAD|FWRITE, kauth_cred_get())) != 0) |
305 | return err; |
306 | } |
307 | |
308 | return err; |
309 | |
310 | } |
311 | /* Destroy target specific data. */ |
312 | int |
313 | dm_target_stripe_destroy(dm_table_entry_t * table_en) |
314 | { |
315 | dm_target_stripe_fini(table_en->target_config); |
316 | |
317 | /* Unbusy target so we can unload it */ |
318 | dm_target_unbusy(table_en->target); |
319 | |
320 | table_en->target_config = NULL; |
321 | return 0; |
322 | } |
323 | /* Doesn't not need to do anything here. */ |
324 | int |
325 | dm_target_stripe_deps(dm_table_entry_t * table_en, prop_array_t prop_array) |
326 | { |
327 | dm_target_stripe_config_t *tsc; |
328 | dm_target_linear_config_t *tlc; |
329 | |
330 | if (table_en->target_config == NULL) |
331 | return ENOENT; |
332 | |
333 | tsc = table_en->target_config; |
334 | |
335 | TAILQ_FOREACH(tlc, &tsc->stripe_devs, entries) { |
336 | prop_array_add_uint64(prop_array, |
337 | (uint64_t) tlc->pdev->pdev_vnode->v_rdev); |
338 | } |
339 | |
340 | return 0; |
341 | } |
342 | /* Unsupported for this target. */ |
343 | int |
344 | dm_target_stripe_upcall(dm_table_entry_t * table_en, struct buf * bp) |
345 | { |
346 | return 0; |
347 | } |
348 | /* |
349 | * Compute physical block size |
350 | * For a stripe target we chose the maximum sector size of all |
351 | * stripe devices. For the supported power-of-2 sizes this is equivalent |
352 | * to the least common multiple. |
353 | */ |
354 | int |
355 | dm_target_stripe_secsize(dm_table_entry_t * table_en, unsigned *secsizep) |
356 | { |
357 | dm_target_linear_config_t *tlc; |
358 | dm_target_stripe_config_t *tsc; |
359 | unsigned secsize; |
360 | |
361 | secsize = 0; |
362 | |
363 | tsc = table_en->target_config; |
364 | if (tsc != NULL) { |
365 | TAILQ_FOREACH(tlc, &tsc->stripe_devs, entries) { |
366 | if (secsize < tlc->pdev->pdev_secsize) |
367 | secsize = tlc->pdev->pdev_secsize; |
368 | } |
369 | } |
370 | |
371 | *secsizep = secsize; |
372 | |
373 | return 0; |
374 | } |
375 | |