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
25 #include "config-host.h"
28 #include "qemu-common.h"
29 #include "qemu/config-file.h"
30 #include "qemu/error-report.h"
31 #include "block/block_int.h"
35 #include "sysemu/sysemu.h"
36 #include <nfsc/libnfs.h>
38 #define QEMU_NFS_MAX_READAHEAD_SIZE 1048576
40 typedef struct NFSClient {
41 struct nfs_context *context;
45 AioContext *aio_context;
48 typedef struct NFSRPC {
58 static void nfs_process_read(void *arg);
59 static void nfs_process_write(void *arg);
61 static void nfs_set_events(NFSClient *client)
63 int ev = nfs_which_events(client->context);
64 if (ev != client->events) {
65 aio_set_fd_handler(client->aio_context,
66 nfs_get_fd(client->context),
67 (ev & POLLIN) ? nfs_process_read : NULL,
68 (ev & POLLOUT) ? nfs_process_write : NULL,
75 static void nfs_process_read(void *arg)
77 NFSClient *client = arg;
78 nfs_service(client->context, POLLIN);
79 nfs_set_events(client);
82 static void nfs_process_write(void *arg)
84 NFSClient *client = arg;
85 nfs_service(client->context, POLLOUT);
86 nfs_set_events(client);
89 static void nfs_co_init_task(NFSClient *client, NFSRPC *task)
92 .co = qemu_coroutine_self(),
97 static void nfs_co_generic_bh_cb(void *opaque)
99 NFSRPC *task = opaque;
101 qemu_bh_delete(task->bh);
102 qemu_coroutine_enter(task->co, NULL);
106 nfs_co_generic_cb(int ret, struct nfs_context *nfs, void *data,
109 NFSRPC *task = private_data;
111 if (task->ret > 0 && task->iov) {
112 if (task->ret <= task->iov->size) {
113 qemu_iovec_from_buf(task->iov, 0, data, task->ret);
118 if (task->ret == 0 && task->st) {
119 memcpy(task->st, data, sizeof(struct stat));
122 error_report("NFS Error: %s", nfs_get_error(nfs));
125 task->bh = aio_bh_new(task->client->aio_context,
126 nfs_co_generic_bh_cb, task);
127 qemu_bh_schedule(task->bh);
133 static int coroutine_fn nfs_co_readv(BlockDriverState *bs,
134 int64_t sector_num, int nb_sectors,
137 NFSClient *client = bs->opaque;
140 nfs_co_init_task(client, &task);
143 if (nfs_pread_async(client->context, client->fh,
144 sector_num * BDRV_SECTOR_SIZE,
145 nb_sectors * BDRV_SECTOR_SIZE,
146 nfs_co_generic_cb, &task) != 0) {
150 while (!task.complete) {
151 nfs_set_events(client);
152 qemu_coroutine_yield();
159 /* zero pad short reads */
160 if (task.ret < iov->size) {
161 qemu_iovec_memset(iov, task.ret, 0, iov->size - task.ret);
167 static int coroutine_fn nfs_co_writev(BlockDriverState *bs,
168 int64_t sector_num, int nb_sectors,
171 NFSClient *client = bs->opaque;
175 nfs_co_init_task(client, &task);
177 buf = g_try_malloc(nb_sectors * BDRV_SECTOR_SIZE);
178 if (nb_sectors && buf == NULL) {
182 qemu_iovec_to_buf(iov, 0, buf, nb_sectors * BDRV_SECTOR_SIZE);
184 if (nfs_pwrite_async(client->context, client->fh,
185 sector_num * BDRV_SECTOR_SIZE,
186 nb_sectors * BDRV_SECTOR_SIZE,
187 buf, nfs_co_generic_cb, &task) != 0) {
192 while (!task.complete) {
193 nfs_set_events(client);
194 qemu_coroutine_yield();
199 if (task.ret != nb_sectors * BDRV_SECTOR_SIZE) {
200 return task.ret < 0 ? task.ret : -EIO;
206 static int coroutine_fn nfs_co_flush(BlockDriverState *bs)
208 NFSClient *client = bs->opaque;
211 nfs_co_init_task(client, &task);
213 if (nfs_fsync_async(client->context, client->fh, nfs_co_generic_cb,
218 while (!task.complete) {
219 nfs_set_events(client);
220 qemu_coroutine_yield();
226 /* TODO Convert to fine grained options */
227 static QemuOptsList runtime_opts = {
229 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
233 .type = QEMU_OPT_STRING,
234 .help = "URL to the NFS file",
236 { /* end of list */ }
240 static void nfs_detach_aio_context(BlockDriverState *bs)
242 NFSClient *client = bs->opaque;
244 aio_set_fd_handler(client->aio_context,
245 nfs_get_fd(client->context),
250 static void nfs_attach_aio_context(BlockDriverState *bs,
251 AioContext *new_context)
253 NFSClient *client = bs->opaque;
255 client->aio_context = new_context;
256 nfs_set_events(client);
259 static void nfs_client_close(NFSClient *client)
261 if (client->context) {
263 nfs_close(client->context, client->fh);
265 aio_set_fd_handler(client->aio_context,
266 nfs_get_fd(client->context),
268 nfs_destroy_context(client->context);
270 memset(client, 0, sizeof(NFSClient));
273 static void nfs_file_close(BlockDriverState *bs)
275 NFSClient *client = bs->opaque;
276 nfs_client_close(client);
279 static int64_t nfs_client_open(NFSClient *client, const char *filename,
280 int flags, Error **errp)
282 int ret = -EINVAL, i;
285 QueryParams *qp = NULL;
286 char *file = NULL, *strp = NULL;
288 uri = uri_parse(filename);
290 error_setg(errp, "Invalid URL specified");
294 error_setg(errp, "Invalid URL specified");
297 strp = strrchr(uri->path, '/');
299 error_setg(errp, "Invalid URL specified");
302 file = g_strdup(strp);
305 client->context = nfs_init_context();
306 if (client->context == NULL) {
307 error_setg(errp, "Failed to init NFS context");
311 qp = query_params_parse(uri->query);
312 for (i = 0; i < qp->n; i++) {
313 unsigned long long val;
314 if (!qp->p[i].value) {
315 error_setg(errp, "Value for NFS parameter expected: %s",
319 if (parse_uint_full(qp->p[i].value, &val, 0)) {
320 error_setg(errp, "Illegal value for NFS parameter: %s",
324 if (!strcmp(qp->p[i].name, "uid")) {
325 nfs_set_uid(client->context, val);
326 } else if (!strcmp(qp->p[i].name, "gid")) {
327 nfs_set_gid(client->context, val);
328 } else if (!strcmp(qp->p[i].name, "tcp-syncnt")) {
329 nfs_set_tcp_syncnt(client->context, val);
330 #ifdef LIBNFS_FEATURE_READAHEAD
331 } else if (!strcmp(qp->p[i].name, "readahead")) {
332 if (val > QEMU_NFS_MAX_READAHEAD_SIZE) {
333 error_report("NFS Warning: Truncating NFS readahead"
334 " size to %d", QEMU_NFS_MAX_READAHEAD_SIZE);
335 val = QEMU_NFS_MAX_READAHEAD_SIZE;
337 nfs_set_readahead(client->context, val);
340 error_setg(errp, "Unknown NFS parameter name: %s",
346 ret = nfs_mount(client->context, uri->server, uri->path);
348 error_setg(errp, "Failed to mount nfs share: %s",
349 nfs_get_error(client->context));
353 if (flags & O_CREAT) {
354 ret = nfs_creat(client->context, file, 0600, &client->fh);
356 error_setg(errp, "Failed to create file: %s",
357 nfs_get_error(client->context));
361 ret = nfs_open(client->context, file, flags, &client->fh);
363 error_setg(errp, "Failed to open file : %s",
364 nfs_get_error(client->context));
369 ret = nfs_fstat(client->context, client->fh, &st);
371 error_setg(errp, "Failed to fstat file: %s",
372 nfs_get_error(client->context));
376 ret = DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE);
377 client->has_zero_init = S_ISREG(st.st_mode);
380 nfs_client_close(client);
383 query_params_free(qp);
390 static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags,
392 NFSClient *client = bs->opaque;
395 Error *local_err = NULL;
397 client->aio_context = bdrv_get_aio_context(bs);
399 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
400 qemu_opts_absorb_qdict(opts, options, &local_err);
402 error_propagate(errp, local_err);
406 ret = nfs_client_open(client, qemu_opt_get(opts, "filename"),
407 (flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY,
412 bs->total_sectors = ret;
419 static QemuOptsList nfs_create_opts = {
420 .name = "nfs-create-opts",
421 .head = QTAILQ_HEAD_INITIALIZER(nfs_create_opts.head),
424 .name = BLOCK_OPT_SIZE,
425 .type = QEMU_OPT_SIZE,
426 .help = "Virtual disk size"
428 { /* end of list */ }
432 static int nfs_file_create(const char *url, QemuOpts *opts, Error **errp)
435 int64_t total_size = 0;
436 NFSClient *client = g_new0(NFSClient, 1);
438 client->aio_context = qemu_get_aio_context();
440 /* Read out options */
441 total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
444 ret = nfs_client_open(client, url, O_CREAT, errp);
448 ret = nfs_ftruncate(client->context, client->fh, total_size);
449 nfs_client_close(client);
455 static int nfs_has_zero_init(BlockDriverState *bs)
457 NFSClient *client = bs->opaque;
458 return client->has_zero_init;
461 static int64_t nfs_get_allocated_file_size(BlockDriverState *bs)
463 NFSClient *client = bs->opaque;
468 if (nfs_fstat_async(client->context, client->fh, nfs_co_generic_cb,
473 while (!task.complete) {
474 nfs_set_events(client);
475 aio_poll(client->aio_context, true);
478 return (task.ret < 0 ? task.ret : st.st_blocks * st.st_blksize);
481 static int nfs_file_truncate(BlockDriverState *bs, int64_t offset)
483 NFSClient *client = bs->opaque;
484 return nfs_ftruncate(client->context, client->fh, offset);
487 static BlockDriver bdrv_nfs = {
488 .format_name = "nfs",
489 .protocol_name = "nfs",
491 .instance_size = sizeof(NFSClient),
492 .bdrv_needs_filename = true,
493 .create_opts = &nfs_create_opts,
495 .bdrv_has_zero_init = nfs_has_zero_init,
496 .bdrv_get_allocated_file_size = nfs_get_allocated_file_size,
497 .bdrv_truncate = nfs_file_truncate,
499 .bdrv_file_open = nfs_file_open,
500 .bdrv_close = nfs_file_close,
501 .bdrv_create = nfs_file_create,
503 .bdrv_co_readv = nfs_co_readv,
504 .bdrv_co_writev = nfs_co_writev,
505 .bdrv_co_flush_to_disk = nfs_co_flush,
507 .bdrv_detach_aio_context = nfs_detach_aio_context,
508 .bdrv_attach_aio_context = nfs_attach_aio_context,
511 static void nfs_block_init(void)
513 bdrv_register(&bdrv_nfs);
516 block_init(nfs_block_init);