Line data Source code
1 : /* SPDX-License-Identifier: BSD-3-Clause
2 : * Copyright (C) 2017 Intel Corporation.
3 : * All rights reserved.
4 : */
5 :
6 : #include "spdk/string.h"
7 : #include "spdk/env.h"
8 : #include "spdk/rpc.h"
9 : #include "spdk/util.h"
10 :
11 : #include <linux/nbd.h>
12 :
13 : #include "nbd_internal.h"
14 : #include "spdk/log.h"
15 :
16 : struct rpc_nbd_start_disk {
17 : char *bdev_name;
18 : char *nbd_device;
19 : /* Used to search one available nbd device */
20 : int nbd_idx;
21 : bool nbd_idx_specified;
22 : struct spdk_jsonrpc_request *request;
23 : };
24 :
25 : static void
26 0 : free_rpc_nbd_start_disk(struct rpc_nbd_start_disk *req)
27 : {
28 0 : free(req->bdev_name);
29 0 : free(req->nbd_device);
30 0 : free(req);
31 0 : }
32 :
33 : static const struct spdk_json_object_decoder rpc_nbd_start_disk_decoders[] = {
34 : {"bdev_name", offsetof(struct rpc_nbd_start_disk, bdev_name), spdk_json_decode_string},
35 : {"nbd_device", offsetof(struct rpc_nbd_start_disk, nbd_device), spdk_json_decode_string, true},
36 : };
37 :
38 : /* Return 0 to indicate the nbd_device might be available,
39 : * or non-zero to indicate the nbd_device is invalid or in use.
40 : */
41 : static int
42 0 : check_available_nbd_disk(char *nbd_device)
43 : {
44 : char nbd_block_path[256];
45 : char tail[2];
46 : int rc;
47 : unsigned int nbd_idx;
48 : struct spdk_nbd_disk *nbd;
49 :
50 : /* nbd device path must be in format of /dev/nbd<num>, with no tail. */
51 0 : rc = sscanf(nbd_device, "/dev/nbd%u%1s", &nbd_idx, tail);
52 0 : if (rc != 1) {
53 0 : return -errno;
54 : }
55 :
56 : /* make sure nbd_device is not registered inside SPDK */
57 0 : nbd = nbd_disk_find_by_nbd_path(nbd_device);
58 0 : if (nbd) {
59 : /* nbd_device is in use */
60 0 : return -EBUSY;
61 : }
62 :
63 : /* A valid pid file in /sys/block indicates the device is in use */
64 0 : snprintf(nbd_block_path, 256, "/sys/block/nbd%u/pid", nbd_idx);
65 :
66 0 : rc = open(nbd_block_path, O_RDONLY);
67 0 : if (rc < 0) {
68 0 : if (errno == ENOENT) {
69 : /* nbd_device might be available */
70 0 : return 0;
71 : } else {
72 0 : SPDK_ERRLOG("Failed to check PID file %s: %s\n", nbd_block_path, spdk_strerror(errno));
73 0 : return -errno;
74 : }
75 : }
76 :
77 0 : close(rc);
78 :
79 : /* nbd_device is in use */
80 0 : return -EBUSY;
81 : }
82 :
83 : static char *
84 0 : find_available_nbd_disk(int nbd_idx, int *next_nbd_idx)
85 : {
86 : int i, rc;
87 : char nbd_device[20];
88 :
89 0 : for (i = nbd_idx; ; i++) {
90 0 : snprintf(nbd_device, 20, "/dev/nbd%d", i);
91 : /* Check whether an nbd device exists in order to reach the last one nbd device */
92 0 : rc = access(nbd_device, F_OK);
93 0 : if (rc != 0) {
94 0 : break;
95 : }
96 :
97 0 : rc = check_available_nbd_disk(nbd_device);
98 0 : if (rc == 0) {
99 0 : if (next_nbd_idx != NULL) {
100 0 : *next_nbd_idx = i + 1;
101 : }
102 :
103 0 : return strdup(nbd_device);
104 : }
105 : }
106 :
107 0 : return NULL;
108 : }
109 :
110 : static void
111 0 : rpc_start_nbd_done(void *cb_arg, struct spdk_nbd_disk *nbd, int rc)
112 : {
113 0 : struct rpc_nbd_start_disk *req = cb_arg;
114 0 : struct spdk_jsonrpc_request *request = req->request;
115 : struct spdk_json_write_ctx *w;
116 :
117 : /* Check whether it's automatic nbd-device assignment */
118 0 : if (rc == -EBUSY && req->nbd_idx_specified == false) {
119 0 : free(req->nbd_device);
120 :
121 0 : req->nbd_device = find_available_nbd_disk(req->nbd_idx, &req->nbd_idx);
122 0 : if (req->nbd_device != NULL) {
123 0 : spdk_nbd_start(req->bdev_name, req->nbd_device,
124 : rpc_start_nbd_done, req);
125 0 : return;
126 : }
127 :
128 0 : SPDK_INFOLOG(nbd, "There is no available nbd device.\n");
129 : }
130 :
131 0 : if (rc) {
132 0 : spdk_jsonrpc_send_error_response(request, rc, spdk_strerror(-rc));
133 0 : free_rpc_nbd_start_disk(req);
134 0 : return;
135 : }
136 :
137 0 : w = spdk_jsonrpc_begin_result(request);
138 0 : spdk_json_write_string(w, spdk_nbd_get_path(nbd));
139 0 : spdk_jsonrpc_end_result(request, w);
140 :
141 0 : free_rpc_nbd_start_disk(req);
142 : }
143 :
144 : static void
145 0 : rpc_nbd_start_disk(struct spdk_jsonrpc_request *request,
146 : const struct spdk_json_val *params)
147 : {
148 : struct rpc_nbd_start_disk *req;
149 : int rc;
150 :
151 0 : req = calloc(1, sizeof(*req));
152 0 : if (req == NULL) {
153 0 : SPDK_ERRLOG("could not allocate nbd_start_disk request.\n");
154 0 : spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR, "Out of memory");
155 0 : return;
156 : }
157 :
158 0 : if (spdk_json_decode_object(params, rpc_nbd_start_disk_decoders,
159 : SPDK_COUNTOF(rpc_nbd_start_disk_decoders),
160 : req)) {
161 0 : SPDK_ERRLOG("spdk_json_decode_object failed\n");
162 0 : spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR,
163 : "spdk_json_decode_object failed");
164 0 : goto invalid;
165 : }
166 :
167 0 : if (req->bdev_name == NULL) {
168 0 : goto invalid;
169 : }
170 :
171 0 : if (req->nbd_device != NULL) {
172 0 : req->nbd_idx_specified = true;
173 0 : rc = check_available_nbd_disk(req->nbd_device);
174 0 : if (rc == -EBUSY) {
175 0 : SPDK_DEBUGLOG(nbd, "NBD device %s is in use.\n", req->nbd_device);
176 0 : spdk_jsonrpc_send_error_response(request, -EBUSY, spdk_strerror(-rc));
177 0 : goto invalid;
178 : }
179 :
180 0 : if (rc != 0) {
181 0 : SPDK_DEBUGLOG(nbd, "Illegal nbd_device %s.\n", req->nbd_device);
182 0 : spdk_jsonrpc_send_error_response_fmt(request, -ENODEV,
183 : "illegal nbd device %s", req->nbd_device);
184 0 : goto invalid;
185 : }
186 : } else {
187 0 : req->nbd_idx = 0;
188 0 : req->nbd_device = find_available_nbd_disk(req->nbd_idx, &req->nbd_idx);
189 0 : if (req->nbd_device == NULL) {
190 0 : SPDK_INFOLOG(nbd, "There is no available nbd device.\n");
191 0 : spdk_jsonrpc_send_error_response(request, -ENODEV,
192 : "nbd device not found");
193 0 : goto invalid;
194 : }
195 : }
196 :
197 0 : req->request = request;
198 0 : spdk_nbd_start(req->bdev_name, req->nbd_device,
199 : rpc_start_nbd_done, req);
200 :
201 0 : return;
202 :
203 0 : invalid:
204 0 : free_rpc_nbd_start_disk(req);
205 : }
206 :
207 0 : SPDK_RPC_REGISTER("nbd_start_disk", rpc_nbd_start_disk, SPDK_RPC_RUNTIME)
208 :
209 : struct rpc_nbd_stop_disk {
210 : char *nbd_device;
211 : };
212 :
213 : static void
214 0 : free_rpc_nbd_stop_disk(struct rpc_nbd_stop_disk *req)
215 : {
216 0 : free(req->nbd_device);
217 0 : }
218 :
219 : static const struct spdk_json_object_decoder rpc_nbd_stop_disk_decoders[] = {
220 : {"nbd_device", offsetof(struct rpc_nbd_stop_disk, nbd_device), spdk_json_decode_string},
221 : };
222 :
223 : struct nbd_disconnect_arg {
224 : struct spdk_jsonrpc_request *request;
225 : struct spdk_nbd_disk *nbd;
226 : };
227 :
228 : static void *
229 0 : nbd_disconnect_thread(void *arg)
230 : {
231 0 : struct nbd_disconnect_arg *thd_arg = arg;
232 :
233 0 : spdk_unaffinitize_thread();
234 :
235 0 : nbd_disconnect(thd_arg->nbd);
236 :
237 0 : spdk_jsonrpc_send_bool_response(thd_arg->request, true);
238 :
239 0 : free(thd_arg);
240 0 : pthread_exit(NULL);
241 : }
242 :
243 : static void
244 0 : rpc_nbd_stop_disk(struct spdk_jsonrpc_request *request,
245 : const struct spdk_json_val *params)
246 : {
247 0 : struct rpc_nbd_stop_disk req = {};
248 : struct spdk_nbd_disk *nbd;
249 : pthread_t tid;
250 0 : struct nbd_disconnect_arg *thd_arg = NULL;
251 : int rc;
252 :
253 0 : if (spdk_json_decode_object(params, rpc_nbd_stop_disk_decoders,
254 : SPDK_COUNTOF(rpc_nbd_stop_disk_decoders),
255 : &req)) {
256 0 : SPDK_ERRLOG("spdk_json_decode_object failed\n");
257 0 : spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR,
258 : "spdk_json_decode_object failed");
259 0 : goto out;
260 : }
261 :
262 0 : if (req.nbd_device == NULL) {
263 0 : spdk_jsonrpc_send_error_response(request, -ENODEV, "invalid nbd device");
264 0 : goto out;
265 : }
266 :
267 : /* make sure nbd_device is registered */
268 0 : nbd = nbd_disk_find_by_nbd_path(req.nbd_device);
269 0 : if (!nbd) {
270 0 : spdk_jsonrpc_send_error_response(request, -ENODEV, spdk_strerror(ENODEV));
271 0 : goto out;
272 : }
273 :
274 : /*
275 : * thd_arg should be freed by created thread
276 : * if thread is created successfully.
277 : */
278 0 : thd_arg = malloc(sizeof(*thd_arg));
279 0 : if (!thd_arg) {
280 0 : SPDK_ERRLOG("could not allocate nbd disconnect thread arg\n");
281 0 : spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR, "Out of memory");
282 0 : goto out;
283 : }
284 :
285 0 : thd_arg->request = request;
286 0 : thd_arg->nbd = nbd;
287 :
288 : /*
289 : * NBD ioctl of disconnect will block until data are flushed.
290 : * Create separate thread to execute it.
291 : */
292 0 : rc = pthread_create(&tid, NULL, nbd_disconnect_thread, (void *)thd_arg);
293 0 : if (rc != 0) {
294 0 : SPDK_ERRLOG("could not create nbd disconnect thread: %s\n", spdk_strerror(rc));
295 0 : spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR, spdk_strerror(rc));
296 0 : free(thd_arg);
297 0 : goto out;
298 : }
299 :
300 0 : rc = pthread_detach(tid);
301 0 : if (rc != 0) {
302 0 : SPDK_ERRLOG("could not detach nbd disconnect thread: %s\n", spdk_strerror(rc));
303 0 : goto out;
304 : }
305 :
306 0 : out:
307 0 : free_rpc_nbd_stop_disk(&req);
308 0 : }
309 :
310 0 : SPDK_RPC_REGISTER("nbd_stop_disk", rpc_nbd_stop_disk, SPDK_RPC_RUNTIME)
311 :
312 : static void
313 0 : rpc_dump_nbd_info(struct spdk_json_write_ctx *w,
314 : struct spdk_nbd_disk *nbd)
315 : {
316 0 : spdk_json_write_object_begin(w);
317 :
318 0 : spdk_json_write_named_string(w, "nbd_device", nbd_disk_get_nbd_path(nbd));
319 :
320 0 : spdk_json_write_named_string(w, "bdev_name", nbd_disk_get_bdev_name(nbd));
321 :
322 0 : spdk_json_write_object_end(w);
323 0 : }
324 :
325 : struct rpc_nbd_get_disks {
326 : char *nbd_device;
327 : };
328 :
329 : static void
330 0 : free_rpc_nbd_get_disks(struct rpc_nbd_get_disks *r)
331 : {
332 0 : free(r->nbd_device);
333 0 : }
334 :
335 : static const struct spdk_json_object_decoder rpc_nbd_get_disks_decoders[] = {
336 : {"nbd_device", offsetof(struct rpc_nbd_get_disks, nbd_device), spdk_json_decode_string, true},
337 : };
338 :
339 : static void
340 0 : rpc_nbd_get_disks(struct spdk_jsonrpc_request *request,
341 : const struct spdk_json_val *params)
342 : {
343 0 : struct rpc_nbd_get_disks req = {};
344 : struct spdk_json_write_ctx *w;
345 0 : struct spdk_nbd_disk *nbd = NULL;
346 :
347 0 : if (params != NULL) {
348 0 : if (spdk_json_decode_object(params, rpc_nbd_get_disks_decoders,
349 : SPDK_COUNTOF(rpc_nbd_get_disks_decoders),
350 : &req)) {
351 0 : SPDK_ERRLOG("spdk_json_decode_object failed\n");
352 0 : spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR,
353 : "spdk_json_decode_object failed");
354 0 : goto invalid;
355 : }
356 :
357 0 : if (req.nbd_device) {
358 0 : nbd = nbd_disk_find_by_nbd_path(req.nbd_device);
359 0 : if (nbd == NULL) {
360 0 : SPDK_ERRLOG("nbd device '%s' does not exist\n", req.nbd_device);
361 0 : spdk_jsonrpc_send_error_response(request, -ENODEV, spdk_strerror(ENODEV));
362 0 : goto invalid;
363 : }
364 :
365 0 : free_rpc_nbd_get_disks(&req);
366 : }
367 : }
368 :
369 0 : w = spdk_jsonrpc_begin_result(request);
370 0 : spdk_json_write_array_begin(w);
371 :
372 0 : if (nbd != NULL) {
373 0 : rpc_dump_nbd_info(w, nbd);
374 : } else {
375 0 : for (nbd = nbd_disk_first(); nbd != NULL; nbd = nbd_disk_next(nbd)) {
376 0 : rpc_dump_nbd_info(w, nbd);
377 : }
378 : }
379 :
380 0 : spdk_json_write_array_end(w);
381 :
382 0 : spdk_jsonrpc_end_result(request, w);
383 :
384 0 : return;
385 :
386 0 : invalid:
387 0 : free_rpc_nbd_get_disks(&req);
388 : }
389 0 : SPDK_RPC_REGISTER("nbd_get_disks", rpc_nbd_get_disks, SPDK_RPC_RUNTIME)
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