block: vpc - use block layer ops in vpc_create, instead of posix calls
[qemu.git] / block / nfs.c
blob8439e0d38964a8e522f09e0e9cbadd6a2484db92
1 /*
2 * QEMU Block driver for native access to files on NFS shares
4 * Copyright (c) 2014 Peter Lieven <pl@kamp.de>
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
25 #include "config-host.h"
27 #include <poll.h>
28 #include "qemu-common.h"
29 #include "qemu/config-file.h"
30 #include "qemu/error-report.h"
31 #include "block/block_int.h"
32 #include "trace.h"
33 #include "qemu/iov.h"
34 #include "qemu/uri.h"
35 #include "sysemu/sysemu.h"
36 #include <nfsc/libnfs.h>
38 typedef struct NFSClient {
39 struct nfs_context *context;
40 struct nfsfh *fh;
41 int events;
42 bool has_zero_init;
43 AioContext *aio_context;
44 } NFSClient;
46 typedef struct NFSRPC {
47 int ret;
48 int complete;
49 QEMUIOVector *iov;
50 struct stat *st;
51 Coroutine *co;
52 QEMUBH *bh;
53 NFSClient *client;
54 } NFSRPC;
56 static void nfs_process_read(void *arg);
57 static void nfs_process_write(void *arg);
59 static void nfs_set_events(NFSClient *client)
61 int ev = nfs_which_events(client->context);
62 if (ev != client->events) {
63 aio_set_fd_handler(client->aio_context,
64 nfs_get_fd(client->context),
65 (ev & POLLIN) ? nfs_process_read : NULL,
66 (ev & POLLOUT) ? nfs_process_write : NULL,
67 client);
70 client->events = ev;
73 static void nfs_process_read(void *arg)
75 NFSClient *client = arg;
76 nfs_service(client->context, POLLIN);
77 nfs_set_events(client);
80 static void nfs_process_write(void *arg)
82 NFSClient *client = arg;
83 nfs_service(client->context, POLLOUT);
84 nfs_set_events(client);
87 static void nfs_co_init_task(NFSClient *client, NFSRPC *task)
89 *task = (NFSRPC) {
90 .co = qemu_coroutine_self(),
91 .client = client,
95 static void nfs_co_generic_bh_cb(void *opaque)
97 NFSRPC *task = opaque;
98 task->complete = 1;
99 qemu_bh_delete(task->bh);
100 qemu_coroutine_enter(task->co, NULL);
103 static void
104 nfs_co_generic_cb(int ret, struct nfs_context *nfs, void *data,
105 void *private_data)
107 NFSRPC *task = private_data;
108 task->ret = ret;
109 if (task->ret > 0 && task->iov) {
110 if (task->ret <= task->iov->size) {
111 qemu_iovec_from_buf(task->iov, 0, data, task->ret);
112 } else {
113 task->ret = -EIO;
116 if (task->ret == 0 && task->st) {
117 memcpy(task->st, data, sizeof(struct stat));
119 if (task->ret < 0) {
120 error_report("NFS Error: %s", nfs_get_error(nfs));
122 if (task->co) {
123 task->bh = aio_bh_new(task->client->aio_context,
124 nfs_co_generic_bh_cb, task);
125 qemu_bh_schedule(task->bh);
126 } else {
127 task->complete = 1;
131 static int coroutine_fn nfs_co_readv(BlockDriverState *bs,
132 int64_t sector_num, int nb_sectors,
133 QEMUIOVector *iov)
135 NFSClient *client = bs->opaque;
136 NFSRPC task;
138 nfs_co_init_task(client, &task);
139 task.iov = iov;
141 if (nfs_pread_async(client->context, client->fh,
142 sector_num * BDRV_SECTOR_SIZE,
143 nb_sectors * BDRV_SECTOR_SIZE,
144 nfs_co_generic_cb, &task) != 0) {
145 return -ENOMEM;
148 while (!task.complete) {
149 nfs_set_events(client);
150 qemu_coroutine_yield();
153 if (task.ret < 0) {
154 return task.ret;
157 /* zero pad short reads */
158 if (task.ret < iov->size) {
159 qemu_iovec_memset(iov, task.ret, 0, iov->size - task.ret);
162 return 0;
165 static int coroutine_fn nfs_co_writev(BlockDriverState *bs,
166 int64_t sector_num, int nb_sectors,
167 QEMUIOVector *iov)
169 NFSClient *client = bs->opaque;
170 NFSRPC task;
171 char *buf = NULL;
173 nfs_co_init_task(client, &task);
175 buf = g_malloc(nb_sectors * BDRV_SECTOR_SIZE);
176 qemu_iovec_to_buf(iov, 0, buf, nb_sectors * BDRV_SECTOR_SIZE);
178 if (nfs_pwrite_async(client->context, client->fh,
179 sector_num * BDRV_SECTOR_SIZE,
180 nb_sectors * BDRV_SECTOR_SIZE,
181 buf, nfs_co_generic_cb, &task) != 0) {
182 g_free(buf);
183 return -ENOMEM;
186 while (!task.complete) {
187 nfs_set_events(client);
188 qemu_coroutine_yield();
191 g_free(buf);
193 if (task.ret != nb_sectors * BDRV_SECTOR_SIZE) {
194 return task.ret < 0 ? task.ret : -EIO;
197 return 0;
200 static int coroutine_fn nfs_co_flush(BlockDriverState *bs)
202 NFSClient *client = bs->opaque;
203 NFSRPC task;
205 nfs_co_init_task(client, &task);
207 if (nfs_fsync_async(client->context, client->fh, nfs_co_generic_cb,
208 &task) != 0) {
209 return -ENOMEM;
212 while (!task.complete) {
213 nfs_set_events(client);
214 qemu_coroutine_yield();
217 return task.ret;
220 /* TODO Convert to fine grained options */
221 static QemuOptsList runtime_opts = {
222 .name = "nfs",
223 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
224 .desc = {
226 .name = "filename",
227 .type = QEMU_OPT_STRING,
228 .help = "URL to the NFS file",
230 { /* end of list */ }
234 static void nfs_detach_aio_context(BlockDriverState *bs)
236 NFSClient *client = bs->opaque;
238 aio_set_fd_handler(client->aio_context,
239 nfs_get_fd(client->context),
240 NULL, NULL, NULL);
241 client->events = 0;
244 static void nfs_attach_aio_context(BlockDriverState *bs,
245 AioContext *new_context)
247 NFSClient *client = bs->opaque;
249 client->aio_context = new_context;
250 nfs_set_events(client);
253 static void nfs_client_close(NFSClient *client)
255 if (client->context) {
256 if (client->fh) {
257 nfs_close(client->context, client->fh);
259 aio_set_fd_handler(client->aio_context,
260 nfs_get_fd(client->context),
261 NULL, NULL, NULL);
262 nfs_destroy_context(client->context);
264 memset(client, 0, sizeof(NFSClient));
267 static void nfs_file_close(BlockDriverState *bs)
269 NFSClient *client = bs->opaque;
270 nfs_client_close(client);
273 static int64_t nfs_client_open(NFSClient *client, const char *filename,
274 int flags, Error **errp)
276 int ret = -EINVAL, i;
277 struct stat st;
278 URI *uri;
279 QueryParams *qp = NULL;
280 char *file = NULL, *strp = NULL;
282 uri = uri_parse(filename);
283 if (!uri) {
284 error_setg(errp, "Invalid URL specified");
285 goto fail;
287 if (!uri->server) {
288 error_setg(errp, "Invalid URL specified");
289 goto fail;
291 strp = strrchr(uri->path, '/');
292 if (strp == NULL) {
293 error_setg(errp, "Invalid URL specified");
294 goto fail;
296 file = g_strdup(strp);
297 *strp = 0;
299 client->context = nfs_init_context();
300 if (client->context == NULL) {
301 error_setg(errp, "Failed to init NFS context");
302 goto fail;
305 qp = query_params_parse(uri->query);
306 for (i = 0; i < qp->n; i++) {
307 unsigned long long val;
308 if (!qp->p[i].value) {
309 error_setg(errp, "Value for NFS parameter expected: %s",
310 qp->p[i].name);
311 goto fail;
313 if (parse_uint_full(qp->p[i].value, &val, 0)) {
314 error_setg(errp, "Illegal value for NFS parameter: %s",
315 qp->p[i].name);
316 goto fail;
318 if (!strcmp(qp->p[i].name, "uid")) {
319 nfs_set_uid(client->context, val);
320 } else if (!strcmp(qp->p[i].name, "gid")) {
321 nfs_set_gid(client->context, val);
322 } else if (!strcmp(qp->p[i].name, "tcp-syncnt")) {
323 nfs_set_tcp_syncnt(client->context, val);
324 #ifdef LIBNFS_FEATURE_READAHEAD
325 } else if (!strcmp(qp->p[i].name, "readahead")) {
326 nfs_set_readahead(client->context, val);
327 #endif
328 } else {
329 error_setg(errp, "Unknown NFS parameter name: %s",
330 qp->p[i].name);
331 goto fail;
335 ret = nfs_mount(client->context, uri->server, uri->path);
336 if (ret < 0) {
337 error_setg(errp, "Failed to mount nfs share: %s",
338 nfs_get_error(client->context));
339 goto fail;
342 if (flags & O_CREAT) {
343 ret = nfs_creat(client->context, file, 0600, &client->fh);
344 if (ret < 0) {
345 error_setg(errp, "Failed to create file: %s",
346 nfs_get_error(client->context));
347 goto fail;
349 } else {
350 ret = nfs_open(client->context, file, flags, &client->fh);
351 if (ret < 0) {
352 error_setg(errp, "Failed to open file : %s",
353 nfs_get_error(client->context));
354 goto fail;
358 ret = nfs_fstat(client->context, client->fh, &st);
359 if (ret < 0) {
360 error_setg(errp, "Failed to fstat file: %s",
361 nfs_get_error(client->context));
362 goto fail;
365 ret = DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE);
366 client->has_zero_init = S_ISREG(st.st_mode);
367 goto out;
368 fail:
369 nfs_client_close(client);
370 out:
371 if (qp) {
372 query_params_free(qp);
374 uri_free(uri);
375 g_free(file);
376 return ret;
379 static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags,
380 Error **errp) {
381 NFSClient *client = bs->opaque;
382 int64_t ret;
383 QemuOpts *opts;
384 Error *local_err = NULL;
386 client->aio_context = bdrv_get_aio_context(bs);
388 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
389 qemu_opts_absorb_qdict(opts, options, &local_err);
390 if (local_err) {
391 error_propagate(errp, local_err);
392 return -EINVAL;
394 ret = nfs_client_open(client, qemu_opt_get(opts, "filename"),
395 (flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY,
396 errp);
397 if (ret < 0) {
398 return ret;
400 bs->total_sectors = ret;
401 return 0;
404 static int nfs_file_create(const char *url, QemuOpts *opts, Error **errp)
406 int ret = 0;
407 int64_t total_size = 0;
408 NFSClient *client = g_malloc0(sizeof(NFSClient));
410 client->aio_context = qemu_get_aio_context();
412 /* Read out options */
413 total_size = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0);
415 ret = nfs_client_open(client, url, O_CREAT, errp);
416 if (ret < 0) {
417 goto out;
419 ret = nfs_ftruncate(client->context, client->fh, total_size);
420 nfs_client_close(client);
421 out:
422 g_free(client);
423 return ret;
426 static int nfs_has_zero_init(BlockDriverState *bs)
428 NFSClient *client = bs->opaque;
429 return client->has_zero_init;
432 static int64_t nfs_get_allocated_file_size(BlockDriverState *bs)
434 NFSClient *client = bs->opaque;
435 NFSRPC task = {0};
436 struct stat st;
438 task.st = &st;
439 if (nfs_fstat_async(client->context, client->fh, nfs_co_generic_cb,
440 &task) != 0) {
441 return -ENOMEM;
444 while (!task.complete) {
445 nfs_set_events(client);
446 aio_poll(client->aio_context, true);
449 return (task.ret < 0 ? task.ret : st.st_blocks * st.st_blksize);
452 static int nfs_file_truncate(BlockDriverState *bs, int64_t offset)
454 NFSClient *client = bs->opaque;
455 return nfs_ftruncate(client->context, client->fh, offset);
458 static BlockDriver bdrv_nfs = {
459 .format_name = "nfs",
460 .protocol_name = "nfs",
462 .instance_size = sizeof(NFSClient),
463 .bdrv_needs_filename = true,
464 .bdrv_has_zero_init = nfs_has_zero_init,
465 .bdrv_get_allocated_file_size = nfs_get_allocated_file_size,
466 .bdrv_truncate = nfs_file_truncate,
468 .bdrv_file_open = nfs_file_open,
469 .bdrv_close = nfs_file_close,
470 .bdrv_create = nfs_file_create,
472 .bdrv_co_readv = nfs_co_readv,
473 .bdrv_co_writev = nfs_co_writev,
474 .bdrv_co_flush_to_disk = nfs_co_flush,
476 .bdrv_detach_aio_context = nfs_detach_aio_context,
477 .bdrv_attach_aio_context = nfs_attach_aio_context,
480 static void nfs_block_init(void)
482 bdrv_register(&bdrv_nfs);
485 block_init(nfs_block_init);