Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
[qemu/ar7.git] / block / nfs.c
blob8c1968bb415d9a9e542988fd51128b9f302caa1c
1 /*
2 * QEMU Block driver for native access to files on NFS shares
4 * Copyright (c) 2014-2017 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 "qemu/osdep.h"
27 #if !defined(_WIN32)
28 #include <poll.h>
29 #endif
30 #include "qemu/config-file.h"
31 #include "qemu/error-report.h"
32 #include "qapi/error.h"
33 #include "block/block_int.h"
34 #include "block/qdict.h"
35 #include "trace.h"
36 #include "qemu/iov.h"
37 #include "qemu/main-loop.h"
38 #include "qemu/module.h"
39 #include "qemu/option.h"
40 #include "qemu/uri.h"
41 #include "qemu/cutils.h"
42 #include "sysemu/sysemu.h"
43 #include "sysemu/replay.h"
44 #include "qapi/qapi-visit-block-core.h"
45 #include "qapi/qmp/qdict.h"
46 #include "qapi/qmp/qstring.h"
47 #include "qapi/qobject-input-visitor.h"
48 #include "qapi/qobject-output-visitor.h"
49 #include <nfsc/libnfs.h>
52 #define QEMU_NFS_MAX_READAHEAD_SIZE 1048576
53 #define QEMU_NFS_MAX_PAGECACHE_SIZE (8388608 / NFS_BLKSIZE)
54 #define QEMU_NFS_MAX_DEBUG_LEVEL 2
56 typedef struct NFSClient {
57 struct nfs_context *context;
58 struct nfsfh *fh;
59 int events;
60 bool has_zero_init;
61 AioContext *aio_context;
62 QemuMutex mutex;
63 uint64_t st_blocks;
64 bool cache_used;
65 NFSServer *server;
66 char *path;
67 int64_t uid, gid, tcp_syncnt, readahead, pagecache, debug;
68 } NFSClient;
70 typedef struct NFSRPC {
71 BlockDriverState *bs;
72 int ret;
73 int complete;
74 QEMUIOVector *iov;
75 struct stat *st;
76 Coroutine *co;
77 NFSClient *client;
78 } NFSRPC;
80 static int nfs_parse_uri(const char *filename, QDict *options, Error **errp)
82 URI *uri = NULL;
83 QueryParams *qp = NULL;
84 int ret = -EINVAL, i;
86 uri = uri_parse(filename);
87 if (!uri) {
88 error_setg(errp, "Invalid URI specified");
89 goto out;
91 if (g_strcmp0(uri->scheme, "nfs") != 0) {
92 error_setg(errp, "URI scheme must be 'nfs'");
93 goto out;
96 if (!uri->server) {
97 error_setg(errp, "missing hostname in URI");
98 goto out;
101 if (!uri->path) {
102 error_setg(errp, "missing file path in URI");
103 goto out;
106 qp = query_params_parse(uri->query);
107 if (!qp) {
108 error_setg(errp, "could not parse query parameters");
109 goto out;
112 qdict_put_str(options, "server.host", uri->server);
113 qdict_put_str(options, "server.type", "inet");
114 qdict_put_str(options, "path", uri->path);
116 for (i = 0; i < qp->n; i++) {
117 unsigned long long val;
118 if (!qp->p[i].value) {
119 error_setg(errp, "Value for NFS parameter expected: %s",
120 qp->p[i].name);
121 goto out;
123 if (parse_uint_full(qp->p[i].value, &val, 0)) {
124 error_setg(errp, "Illegal value for NFS parameter: %s",
125 qp->p[i].name);
126 goto out;
128 if (!strcmp(qp->p[i].name, "uid")) {
129 qdict_put_str(options, "user", qp->p[i].value);
130 } else if (!strcmp(qp->p[i].name, "gid")) {
131 qdict_put_str(options, "group", qp->p[i].value);
132 } else if (!strcmp(qp->p[i].name, "tcp-syncnt")) {
133 qdict_put_str(options, "tcp-syn-count", qp->p[i].value);
134 } else if (!strcmp(qp->p[i].name, "readahead")) {
135 qdict_put_str(options, "readahead-size", qp->p[i].value);
136 } else if (!strcmp(qp->p[i].name, "pagecache")) {
137 qdict_put_str(options, "page-cache-size", qp->p[i].value);
138 } else if (!strcmp(qp->p[i].name, "debug")) {
139 qdict_put_str(options, "debug", qp->p[i].value);
140 } else {
141 error_setg(errp, "Unknown NFS parameter name: %s",
142 qp->p[i].name);
143 goto out;
146 ret = 0;
147 out:
148 if (qp) {
149 query_params_free(qp);
151 if (uri) {
152 uri_free(uri);
154 return ret;
157 static bool nfs_has_filename_options_conflict(QDict *options, Error **errp)
159 const QDictEntry *qe;
161 for (qe = qdict_first(options); qe; qe = qdict_next(options, qe)) {
162 if (!strcmp(qe->key, "host") ||
163 !strcmp(qe->key, "path") ||
164 !strcmp(qe->key, "user") ||
165 !strcmp(qe->key, "group") ||
166 !strcmp(qe->key, "tcp-syn-count") ||
167 !strcmp(qe->key, "readahead-size") ||
168 !strcmp(qe->key, "page-cache-size") ||
169 !strcmp(qe->key, "debug") ||
170 strstart(qe->key, "server.", NULL))
172 error_setg(errp, "Option %s cannot be used with a filename",
173 qe->key);
174 return true;
178 return false;
181 static void nfs_parse_filename(const char *filename, QDict *options,
182 Error **errp)
184 if (nfs_has_filename_options_conflict(options, errp)) {
185 return;
188 nfs_parse_uri(filename, options, errp);
191 static void nfs_process_read(void *arg);
192 static void nfs_process_write(void *arg);
194 /* Called with QemuMutex held. */
195 static void nfs_set_events(NFSClient *client)
197 int ev = nfs_which_events(client->context);
198 if (ev != client->events) {
199 aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
200 false,
201 (ev & POLLIN) ? nfs_process_read : NULL,
202 (ev & POLLOUT) ? nfs_process_write : NULL,
203 NULL, client);
206 client->events = ev;
209 static void nfs_process_read(void *arg)
211 NFSClient *client = arg;
213 qemu_mutex_lock(&client->mutex);
214 nfs_service(client->context, POLLIN);
215 nfs_set_events(client);
216 qemu_mutex_unlock(&client->mutex);
219 static void nfs_process_write(void *arg)
221 NFSClient *client = arg;
223 qemu_mutex_lock(&client->mutex);
224 nfs_service(client->context, POLLOUT);
225 nfs_set_events(client);
226 qemu_mutex_unlock(&client->mutex);
229 static void nfs_co_init_task(BlockDriverState *bs, NFSRPC *task)
231 *task = (NFSRPC) {
232 .co = qemu_coroutine_self(),
233 .bs = bs,
234 .client = bs->opaque,
238 static void nfs_co_generic_bh_cb(void *opaque)
240 NFSRPC *task = opaque;
242 task->complete = 1;
243 aio_co_wake(task->co);
246 /* Called (via nfs_service) with QemuMutex held. */
247 static void
248 nfs_co_generic_cb(int ret, struct nfs_context *nfs, void *data,
249 void *private_data)
251 NFSRPC *task = private_data;
252 task->ret = ret;
253 assert(!task->st);
254 if (task->ret > 0 && task->iov) {
255 if (task->ret <= task->iov->size) {
256 qemu_iovec_from_buf(task->iov, 0, data, task->ret);
257 } else {
258 task->ret = -EIO;
261 if (task->ret < 0) {
262 error_report("NFS Error: %s", nfs_get_error(nfs));
264 replay_bh_schedule_oneshot_event(task->client->aio_context,
265 nfs_co_generic_bh_cb, task);
268 static int coroutine_fn nfs_co_preadv(BlockDriverState *bs, uint64_t offset,
269 uint64_t bytes, QEMUIOVector *iov,
270 int flags)
272 NFSClient *client = bs->opaque;
273 NFSRPC task;
275 nfs_co_init_task(bs, &task);
276 task.iov = iov;
278 WITH_QEMU_LOCK_GUARD(&client->mutex) {
279 if (nfs_pread_async(client->context, client->fh,
280 offset, bytes, nfs_co_generic_cb, &task) != 0) {
281 return -ENOMEM;
284 nfs_set_events(client);
286 while (!task.complete) {
287 qemu_coroutine_yield();
290 if (task.ret < 0) {
291 return task.ret;
294 /* zero pad short reads */
295 if (task.ret < iov->size) {
296 qemu_iovec_memset(iov, task.ret, 0, iov->size - task.ret);
299 return 0;
302 static int coroutine_fn nfs_co_pwritev(BlockDriverState *bs, uint64_t offset,
303 uint64_t bytes, QEMUIOVector *iov,
304 int flags)
306 NFSClient *client = bs->opaque;
307 NFSRPC task;
308 char *buf = NULL;
309 bool my_buffer = false;
311 nfs_co_init_task(bs, &task);
313 if (iov->niov != 1) {
314 buf = g_try_malloc(bytes);
315 if (bytes && buf == NULL) {
316 return -ENOMEM;
318 qemu_iovec_to_buf(iov, 0, buf, bytes);
319 my_buffer = true;
320 } else {
321 buf = iov->iov[0].iov_base;
324 WITH_QEMU_LOCK_GUARD(&client->mutex) {
325 if (nfs_pwrite_async(client->context, client->fh,
326 offset, bytes, buf,
327 nfs_co_generic_cb, &task) != 0) {
328 if (my_buffer) {
329 g_free(buf);
331 return -ENOMEM;
334 nfs_set_events(client);
336 while (!task.complete) {
337 qemu_coroutine_yield();
340 if (my_buffer) {
341 g_free(buf);
344 if (task.ret != bytes) {
345 return task.ret < 0 ? task.ret : -EIO;
348 return 0;
351 static int coroutine_fn nfs_co_flush(BlockDriverState *bs)
353 NFSClient *client = bs->opaque;
354 NFSRPC task;
356 nfs_co_init_task(bs, &task);
358 WITH_QEMU_LOCK_GUARD(&client->mutex) {
359 if (nfs_fsync_async(client->context, client->fh, nfs_co_generic_cb,
360 &task) != 0) {
361 return -ENOMEM;
364 nfs_set_events(client);
366 while (!task.complete) {
367 qemu_coroutine_yield();
370 return task.ret;
373 static void nfs_detach_aio_context(BlockDriverState *bs)
375 NFSClient *client = bs->opaque;
377 aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
378 false, NULL, NULL, NULL, NULL);
379 client->events = 0;
382 static void nfs_attach_aio_context(BlockDriverState *bs,
383 AioContext *new_context)
385 NFSClient *client = bs->opaque;
387 client->aio_context = new_context;
388 nfs_set_events(client);
391 static void nfs_client_close(NFSClient *client)
393 if (client->context) {
394 qemu_mutex_lock(&client->mutex);
395 aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
396 false, NULL, NULL, NULL, NULL);
397 qemu_mutex_unlock(&client->mutex);
398 if (client->fh) {
399 nfs_close(client->context, client->fh);
400 client->fh = NULL;
402 #ifdef LIBNFS_FEATURE_UMOUNT
403 nfs_umount(client->context);
404 #endif
405 nfs_destroy_context(client->context);
406 client->context = NULL;
408 g_free(client->path);
409 qemu_mutex_destroy(&client->mutex);
410 qapi_free_NFSServer(client->server);
411 client->server = NULL;
414 static void nfs_file_close(BlockDriverState *bs)
416 NFSClient *client = bs->opaque;
417 nfs_client_close(client);
420 static int64_t nfs_client_open(NFSClient *client, BlockdevOptionsNfs *opts,
421 int flags, int open_flags, Error **errp)
423 int64_t ret = -EINVAL;
424 struct stat st;
425 char *file = NULL, *strp = NULL;
427 qemu_mutex_init(&client->mutex);
429 client->path = g_strdup(opts->path);
431 strp = strrchr(client->path, '/');
432 if (strp == NULL) {
433 error_setg(errp, "Invalid URL specified");
434 goto fail;
436 file = g_strdup(strp);
437 *strp = 0;
439 /* Steal the NFSServer object from opts; set the original pointer to NULL
440 * to avoid use after free and double free. */
441 client->server = opts->server;
442 opts->server = NULL;
444 client->context = nfs_init_context();
445 if (client->context == NULL) {
446 error_setg(errp, "Failed to init NFS context");
447 goto fail;
450 if (opts->has_user) {
451 client->uid = opts->user;
452 nfs_set_uid(client->context, client->uid);
455 if (opts->has_group) {
456 client->gid = opts->group;
457 nfs_set_gid(client->context, client->gid);
460 if (opts->has_tcp_syn_count) {
461 client->tcp_syncnt = opts->tcp_syn_count;
462 nfs_set_tcp_syncnt(client->context, client->tcp_syncnt);
465 #ifdef LIBNFS_FEATURE_READAHEAD
466 if (opts->has_readahead_size) {
467 if (open_flags & BDRV_O_NOCACHE) {
468 error_setg(errp, "Cannot enable NFS readahead "
469 "if cache.direct = on");
470 goto fail;
472 client->readahead = opts->readahead_size;
473 if (client->readahead > QEMU_NFS_MAX_READAHEAD_SIZE) {
474 warn_report("Truncating NFS readahead size to %d",
475 QEMU_NFS_MAX_READAHEAD_SIZE);
476 client->readahead = QEMU_NFS_MAX_READAHEAD_SIZE;
478 nfs_set_readahead(client->context, client->readahead);
479 #ifdef LIBNFS_FEATURE_PAGECACHE
480 nfs_set_pagecache_ttl(client->context, 0);
481 #endif
482 client->cache_used = true;
484 #endif
486 #ifdef LIBNFS_FEATURE_PAGECACHE
487 if (opts->has_page_cache_size) {
488 if (open_flags & BDRV_O_NOCACHE) {
489 error_setg(errp, "Cannot enable NFS pagecache "
490 "if cache.direct = on");
491 goto fail;
493 client->pagecache = opts->page_cache_size;
494 if (client->pagecache > QEMU_NFS_MAX_PAGECACHE_SIZE) {
495 warn_report("Truncating NFS pagecache size to %d pages",
496 QEMU_NFS_MAX_PAGECACHE_SIZE);
497 client->pagecache = QEMU_NFS_MAX_PAGECACHE_SIZE;
499 nfs_set_pagecache(client->context, client->pagecache);
500 nfs_set_pagecache_ttl(client->context, 0);
501 client->cache_used = true;
503 #endif
505 #ifdef LIBNFS_FEATURE_DEBUG
506 if (opts->has_debug) {
507 client->debug = opts->debug;
508 /* limit the maximum debug level to avoid potential flooding
509 * of our log files. */
510 if (client->debug > QEMU_NFS_MAX_DEBUG_LEVEL) {
511 warn_report("Limiting NFS debug level to %d",
512 QEMU_NFS_MAX_DEBUG_LEVEL);
513 client->debug = QEMU_NFS_MAX_DEBUG_LEVEL;
515 nfs_set_debug(client->context, client->debug);
517 #endif
519 ret = nfs_mount(client->context, client->server->host, client->path);
520 if (ret < 0) {
521 error_setg(errp, "Failed to mount nfs share: %s",
522 nfs_get_error(client->context));
523 goto fail;
526 if (flags & O_CREAT) {
527 ret = nfs_creat(client->context, file, 0600, &client->fh);
528 if (ret < 0) {
529 error_setg(errp, "Failed to create file: %s",
530 nfs_get_error(client->context));
531 goto fail;
533 } else {
534 ret = nfs_open(client->context, file, flags, &client->fh);
535 if (ret < 0) {
536 error_setg(errp, "Failed to open file : %s",
537 nfs_get_error(client->context));
538 goto fail;
542 ret = nfs_fstat(client->context, client->fh, &st);
543 if (ret < 0) {
544 error_setg(errp, "Failed to fstat file: %s",
545 nfs_get_error(client->context));
546 goto fail;
549 ret = DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE);
550 #if !defined(_WIN32)
551 client->st_blocks = st.st_blocks;
552 #endif
553 client->has_zero_init = S_ISREG(st.st_mode);
554 *strp = '/';
555 goto out;
557 fail:
558 nfs_client_close(client);
559 out:
560 g_free(file);
561 return ret;
564 static BlockdevOptionsNfs *nfs_options_qdict_to_qapi(QDict *options,
565 Error **errp)
567 BlockdevOptionsNfs *opts = NULL;
568 Visitor *v;
569 const QDictEntry *e;
571 v = qobject_input_visitor_new_flat_confused(options, errp);
572 if (!v) {
573 return NULL;
576 visit_type_BlockdevOptionsNfs(v, NULL, &opts, errp);
577 visit_free(v);
578 if (!opts) {
579 return NULL;
582 /* Remove the processed options from the QDict (the visitor processes
583 * _all_ options in the QDict) */
584 while ((e = qdict_first(options))) {
585 qdict_del(options, e->key);
588 return opts;
591 static int64_t nfs_client_open_qdict(NFSClient *client, QDict *options,
592 int flags, int open_flags, Error **errp)
594 BlockdevOptionsNfs *opts;
595 int64_t ret;
597 opts = nfs_options_qdict_to_qapi(options, errp);
598 if (opts == NULL) {
599 ret = -EINVAL;
600 goto fail;
603 ret = nfs_client_open(client, opts, flags, open_flags, errp);
604 fail:
605 qapi_free_BlockdevOptionsNfs(opts);
606 return ret;
609 static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags,
610 Error **errp) {
611 NFSClient *client = bs->opaque;
612 int64_t ret;
614 client->aio_context = bdrv_get_aio_context(bs);
616 ret = nfs_client_open_qdict(client, options,
617 (flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY,
618 bs->open_flags, errp);
619 if (ret < 0) {
620 return ret;
623 bs->total_sectors = ret;
624 if (client->has_zero_init) {
625 bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE;
627 return 0;
630 static QemuOptsList nfs_create_opts = {
631 .name = "nfs-create-opts",
632 .head = QTAILQ_HEAD_INITIALIZER(nfs_create_opts.head),
633 .desc = {
635 .name = BLOCK_OPT_SIZE,
636 .type = QEMU_OPT_SIZE,
637 .help = "Virtual disk size"
639 { /* end of list */ }
643 static int nfs_file_co_create(BlockdevCreateOptions *options, Error **errp)
645 BlockdevCreateOptionsNfs *opts = &options->u.nfs;
646 NFSClient *client = g_new0(NFSClient, 1);
647 int ret;
649 assert(options->driver == BLOCKDEV_DRIVER_NFS);
651 client->aio_context = qemu_get_aio_context();
653 ret = nfs_client_open(client, opts->location, O_CREAT, 0, errp);
654 if (ret < 0) {
655 goto out;
657 ret = nfs_ftruncate(client->context, client->fh, opts->size);
658 nfs_client_close(client);
660 out:
661 g_free(client);
662 return ret;
665 static int coroutine_fn nfs_file_co_create_opts(BlockDriver *drv,
666 const char *url,
667 QemuOpts *opts,
668 Error **errp)
670 BlockdevCreateOptions *create_options;
671 BlockdevCreateOptionsNfs *nfs_opts;
672 QDict *options;
673 int ret;
675 create_options = g_new0(BlockdevCreateOptions, 1);
676 create_options->driver = BLOCKDEV_DRIVER_NFS;
677 nfs_opts = &create_options->u.nfs;
679 /* Read out options */
680 nfs_opts->size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
681 BDRV_SECTOR_SIZE);
683 options = qdict_new();
684 ret = nfs_parse_uri(url, options, errp);
685 if (ret < 0) {
686 goto out;
689 nfs_opts->location = nfs_options_qdict_to_qapi(options, errp);
690 if (nfs_opts->location == NULL) {
691 ret = -EINVAL;
692 goto out;
695 ret = nfs_file_co_create(create_options, errp);
696 if (ret < 0) {
697 goto out;
700 ret = 0;
701 out:
702 qobject_unref(options);
703 qapi_free_BlockdevCreateOptions(create_options);
704 return ret;
707 static int nfs_has_zero_init(BlockDriverState *bs)
709 NFSClient *client = bs->opaque;
710 return client->has_zero_init;
713 #if !defined(_WIN32)
714 /* Called (via nfs_service) with QemuMutex held. */
715 static void
716 nfs_get_allocated_file_size_cb(int ret, struct nfs_context *nfs, void *data,
717 void *private_data)
719 NFSRPC *task = private_data;
720 task->ret = ret;
721 if (task->ret == 0) {
722 memcpy(task->st, data, sizeof(struct stat));
724 if (task->ret < 0) {
725 error_report("NFS Error: %s", nfs_get_error(nfs));
728 /* Set task->complete before reading bs->wakeup. */
729 qatomic_mb_set(&task->complete, 1);
730 bdrv_wakeup(task->bs);
733 static int64_t nfs_get_allocated_file_size(BlockDriverState *bs)
735 NFSClient *client = bs->opaque;
736 NFSRPC task = {0};
737 struct stat st;
739 if (bdrv_is_read_only(bs) &&
740 !(bs->open_flags & BDRV_O_NOCACHE)) {
741 return client->st_blocks * 512;
744 task.bs = bs;
745 task.st = &st;
746 if (nfs_fstat_async(client->context, client->fh, nfs_get_allocated_file_size_cb,
747 &task) != 0) {
748 return -ENOMEM;
751 nfs_set_events(client);
752 BDRV_POLL_WHILE(bs, !task.complete);
754 return (task.ret < 0 ? task.ret : st.st_blocks * 512);
756 #endif
758 static int coroutine_fn
759 nfs_file_co_truncate(BlockDriverState *bs, int64_t offset, bool exact,
760 PreallocMode prealloc, BdrvRequestFlags flags,
761 Error **errp)
763 NFSClient *client = bs->opaque;
764 int ret;
766 if (prealloc != PREALLOC_MODE_OFF) {
767 error_setg(errp, "Unsupported preallocation mode '%s'",
768 PreallocMode_str(prealloc));
769 return -ENOTSUP;
772 ret = nfs_ftruncate(client->context, client->fh, offset);
773 if (ret < 0) {
774 error_setg_errno(errp, -ret, "Failed to truncate file");
775 return ret;
778 return 0;
781 /* Note that this will not re-establish a connection with the NFS server
782 * - it is effectively a NOP. */
783 static int nfs_reopen_prepare(BDRVReopenState *state,
784 BlockReopenQueue *queue, Error **errp)
786 NFSClient *client = state->bs->opaque;
787 struct stat st;
788 int ret = 0;
790 if (state->flags & BDRV_O_RDWR && bdrv_is_read_only(state->bs)) {
791 error_setg(errp, "Cannot open a read-only mount as read-write");
792 return -EACCES;
795 if ((state->flags & BDRV_O_NOCACHE) && client->cache_used) {
796 error_setg(errp, "Cannot disable cache if libnfs readahead or"
797 " pagecache is enabled");
798 return -EINVAL;
801 /* Update cache for read-only reopens */
802 if (!(state->flags & BDRV_O_RDWR)) {
803 ret = nfs_fstat(client->context, client->fh, &st);
804 if (ret < 0) {
805 error_setg(errp, "Failed to fstat file: %s",
806 nfs_get_error(client->context));
807 return ret;
809 #if !defined(_WIN32)
810 client->st_blocks = st.st_blocks;
811 #endif
814 return 0;
817 static void nfs_refresh_filename(BlockDriverState *bs)
819 NFSClient *client = bs->opaque;
821 if (client->uid && !client->gid) {
822 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
823 "nfs://%s%s?uid=%" PRId64, client->server->host, client->path,
824 client->uid);
825 } else if (!client->uid && client->gid) {
826 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
827 "nfs://%s%s?gid=%" PRId64, client->server->host, client->path,
828 client->gid);
829 } else if (client->uid && client->gid) {
830 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
831 "nfs://%s%s?uid=%" PRId64 "&gid=%" PRId64,
832 client->server->host, client->path, client->uid, client->gid);
833 } else {
834 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
835 "nfs://%s%s", client->server->host, client->path);
839 static char *nfs_dirname(BlockDriverState *bs, Error **errp)
841 NFSClient *client = bs->opaque;
843 if (client->uid || client->gid) {
844 bdrv_refresh_filename(bs);
845 error_setg(errp, "Cannot generate a base directory for NFS node '%s'",
846 bs->filename);
847 return NULL;
850 return g_strdup_printf("nfs://%s%s/", client->server->host, client->path);
853 #ifdef LIBNFS_FEATURE_PAGECACHE
854 static void coroutine_fn nfs_co_invalidate_cache(BlockDriverState *bs,
855 Error **errp)
857 NFSClient *client = bs->opaque;
858 nfs_pagecache_invalidate(client->context, client->fh);
860 #endif
862 static const char *nfs_strong_runtime_opts[] = {
863 "path",
864 "user",
865 "group",
866 "server.",
868 NULL
871 static BlockDriver bdrv_nfs = {
872 .format_name = "nfs",
873 .protocol_name = "nfs",
875 .instance_size = sizeof(NFSClient),
876 .bdrv_parse_filename = nfs_parse_filename,
877 .create_opts = &nfs_create_opts,
879 .bdrv_has_zero_init = nfs_has_zero_init,
880 /* libnfs does not provide the allocated filesize of a file on win32. */
881 #if !defined(_WIN32)
882 .bdrv_get_allocated_file_size = nfs_get_allocated_file_size,
883 #endif
884 .bdrv_co_truncate = nfs_file_co_truncate,
886 .bdrv_file_open = nfs_file_open,
887 .bdrv_close = nfs_file_close,
888 .bdrv_co_create = nfs_file_co_create,
889 .bdrv_co_create_opts = nfs_file_co_create_opts,
890 .bdrv_reopen_prepare = nfs_reopen_prepare,
892 .bdrv_co_preadv = nfs_co_preadv,
893 .bdrv_co_pwritev = nfs_co_pwritev,
894 .bdrv_co_flush_to_disk = nfs_co_flush,
896 .bdrv_detach_aio_context = nfs_detach_aio_context,
897 .bdrv_attach_aio_context = nfs_attach_aio_context,
898 .bdrv_refresh_filename = nfs_refresh_filename,
899 .bdrv_dirname = nfs_dirname,
901 .strong_runtime_opts = nfs_strong_runtime_opts,
903 #ifdef LIBNFS_FEATURE_PAGECACHE
904 .bdrv_co_invalidate_cache = nfs_co_invalidate_cache,
905 #endif
908 static void nfs_block_init(void)
910 bdrv_register(&bdrv_nfs);
913 block_init(nfs_block_init);