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129c7d1c53
xemu/block/nfs.c
Markus Armbruster 129c7d1c53 block: Document -drive problematic code and bugs 
-blockdev and blockdev_add convert their arguments via QObject to
BlockdevOptions for qmp_blockdev_add(), which converts them back to
QObject, then to a flattened QDict.  The QDict's members are typed
according to the QAPI schema.

-drive converts its argument via QemuOpts to a (flat) QDict.  This
QDict's members are all QString.

Thus, the QType of a flat QDict member depends on whether it comes
from -drive or -blockdev/blockdev_add, except when the QAPI type maps
to QString, which is the case for 'str' and enumeration types.

The block layer core extracts generic configuration from the flat
QDict, and the block driver extracts driver-specific configuration.

Both commonly do so by converting (parts of) the flat QDict to
QemuOpts, which turns all values into strings.  Not exactly elegant,
but correct.

However, A few places access the flat QDict directly:

* Most of them access members that are always QString.  Correct.

* bdrv_open_inherit() accesses a boolean, carefully.  Correct.

* nfs_config() uses a QObject input visitor.  Correct only because the
  visited type contains nothing but QStrings.

* nbd_config() and ssh_config() use a QObject input visitor, and the
  visited types contain non-QStrings: InetSocketAddress members
  @numeric, @to, @ipv4, @ipv6.  -drive works as long as you don't try
  to use them (they're all optional).  @to is ignored anyway.

  Reproducer:
  -drive driver=ssh,server.host=h,server.port=22,server.ipv4,path=p
  -drive driver=nbd,server.type=inet,server.data.host=h,server.data.port=22,server.data.ipv4
  both fail with "Invalid parameter type for 'data.ipv4', expected: boolean"

Add suitable comments to all these places.  Mark the buggy ones FIXME.

"Fortunately", -drive's driver-specific options are entirely
undocumented.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1490895797-29094-5-git-send-email-armbru@redhat.com
[mreitz: Fixed two typos]
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00

911 lines
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/*
* QEMU Block driver for native access to files on NFS shares
*
* Copyright (c) 2014-2016 Peter Lieven <pl@kamp.de>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include <poll.h>
#include "qemu-common.h"
#include "qemu/config-file.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "block/block_int.h"
#include "trace.h"
#include "qemu/iov.h"
#include "qemu/uri.h"
#include "qemu/cutils.h"
#include "sysemu/sysemu.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qint.h"
#include "qapi/qmp/qstring.h"
#include "qapi-visit.h"
#include "qapi/qobject-input-visitor.h"
#include "qapi/qobject-output-visitor.h"
#include <nfsc/libnfs.h>
#define QEMU_NFS_MAX_READAHEAD_SIZE 1048576
#define QEMU_NFS_MAX_PAGECACHE_SIZE (8388608 / NFS_BLKSIZE)
#define QEMU_NFS_MAX_DEBUG_LEVEL 2
typedef struct NFSClient {
struct nfs_context *context;
struct nfsfh *fh;
int events;
bool has_zero_init;
AioContext *aio_context;
QemuMutex mutex;
blkcnt_t st_blocks;
bool cache_used;
NFSServer *server;
char *path;
int64_t uid, gid, tcp_syncnt, readahead, pagecache, debug;
} NFSClient;
typedef struct NFSRPC {
BlockDriverState *bs;
int ret;
int complete;
QEMUIOVector *iov;
struct stat *st;
Coroutine *co;
NFSClient *client;
} NFSRPC;
static int nfs_parse_uri(const char *filename, QDict *options, Error **errp)
{
URI *uri = NULL;
QueryParams *qp = NULL;
int ret = -EINVAL, i;
uri = uri_parse(filename);
if (!uri) {
error_setg(errp, "Invalid URI specified");
goto out;
}
if (strcmp(uri->scheme, "nfs") != 0) {
error_setg(errp, "URI scheme must be 'nfs'");
goto out;
}
if (!uri->server) {
error_setg(errp, "missing hostname in URI");
goto out;
}
if (!uri->path) {
error_setg(errp, "missing file path in URI");
goto out;
}
qp = query_params_parse(uri->query);
if (!qp) {
error_setg(errp, "could not parse query parameters");
goto out;
}
qdict_put(options, "server.host", qstring_from_str(uri->server));
qdict_put(options, "server.type", qstring_from_str("inet"));
qdict_put(options, "path", qstring_from_str(uri->path));
for (i = 0; i < qp->n; i++) {
unsigned long long val;
if (!qp->p[i].value) {
error_setg(errp, "Value for NFS parameter expected: %s",
qp->p[i].name);
goto out;
}
if (parse_uint_full(qp->p[i].value, &val, 0)) {
error_setg(errp, "Illegal value for NFS parameter: %s",
qp->p[i].name);
goto out;
}
if (!strcmp(qp->p[i].name, "uid")) {
qdict_put(options, "user",
qstring_from_str(qp->p[i].value));
} else if (!strcmp(qp->p[i].name, "gid")) {
qdict_put(options, "group",
qstring_from_str(qp->p[i].value));
} else if (!strcmp(qp->p[i].name, "tcp-syncnt")) {
qdict_put(options, "tcp-syn-count",
qstring_from_str(qp->p[i].value));
} else if (!strcmp(qp->p[i].name, "readahead")) {
qdict_put(options, "readahead-size",
qstring_from_str(qp->p[i].value));
} else if (!strcmp(qp->p[i].name, "pagecache")) {
qdict_put(options, "page-cache-size",
qstring_from_str(qp->p[i].value));
} else if (!strcmp(qp->p[i].name, "debug")) {
qdict_put(options, "debug",
qstring_from_str(qp->p[i].value));
} else {
error_setg(errp, "Unknown NFS parameter name: %s",
qp->p[i].name);
goto out;
}
}
ret = 0;
out:
if (qp) {
query_params_free(qp);
}
if (uri) {
uri_free(uri);
}
return ret;
}
static bool nfs_has_filename_options_conflict(QDict *options, Error **errp)
{
const QDictEntry *qe;
for (qe = qdict_first(options); qe; qe = qdict_next(options, qe)) {
if (!strcmp(qe->key, "host") ||
!strcmp(qe->key, "path") ||
!strcmp(qe->key, "user") ||
!strcmp(qe->key, "group") ||
!strcmp(qe->key, "tcp-syn-count") ||
!strcmp(qe->key, "readahead-size") ||
!strcmp(qe->key, "page-cache-size") ||
!strcmp(qe->key, "debug") ||
strstart(qe->key, "server.", NULL))
{
error_setg(errp, "Option %s cannot be used with a filename",
qe->key);
return true;
}
}
return false;
}
static void nfs_parse_filename(const char *filename, QDict *options,
Error **errp)
{
if (nfs_has_filename_options_conflict(options, errp)) {
return;
}
nfs_parse_uri(filename, options, errp);
}
static void nfs_process_read(void *arg);
static void nfs_process_write(void *arg);
/* Called with QemuMutex held. */
static void nfs_set_events(NFSClient *client)
{
int ev = nfs_which_events(client->context);
if (ev != client->events) {
aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
false,
(ev & POLLIN) ? nfs_process_read : NULL,
(ev & POLLOUT) ? nfs_process_write : NULL,
NULL, client);
}
client->events = ev;
}
static void nfs_process_read(void *arg)
{
NFSClient *client = arg;
qemu_mutex_lock(&client->mutex);
nfs_service(client->context, POLLIN);
nfs_set_events(client);
qemu_mutex_unlock(&client->mutex);
}
static void nfs_process_write(void *arg)
{
NFSClient *client = arg;
qemu_mutex_lock(&client->mutex);
nfs_service(client->context, POLLOUT);
nfs_set_events(client);
qemu_mutex_unlock(&client->mutex);
}
static void nfs_co_init_task(BlockDriverState *bs, NFSRPC *task)
{
*task = (NFSRPC) {
.co = qemu_coroutine_self(),
.bs = bs,
.client = bs->opaque,
};
}
static void nfs_co_generic_bh_cb(void *opaque)
{
NFSRPC *task = opaque;
task->complete = 1;
aio_co_wake(task->co);
}
/* Called (via nfs_service) with QemuMutex held. */
static void
nfs_co_generic_cb(int ret, struct nfs_context *nfs, void *data,
void *private_data)
{
NFSRPC *task = private_data;
task->ret = ret;
assert(!task->st);
if (task->ret > 0 && task->iov) {
if (task->ret <= task->iov->size) {
qemu_iovec_from_buf(task->iov, 0, data, task->ret);
} else {
task->ret = -EIO;
}
}
if (task->ret < 0) {
error_report("NFS Error: %s", nfs_get_error(nfs));
}
aio_bh_schedule_oneshot(task->client->aio_context,
nfs_co_generic_bh_cb, task);
}
static int coroutine_fn nfs_co_preadv(BlockDriverState *bs, uint64_t offset,
uint64_t bytes, QEMUIOVector *iov,
int flags)
{
NFSClient *client = bs->opaque;
NFSRPC task;
nfs_co_init_task(bs, &task);
task.iov = iov;
qemu_mutex_lock(&client->mutex);
if (nfs_pread_async(client->context, client->fh,
offset, bytes, nfs_co_generic_cb, &task) != 0) {
qemu_mutex_unlock(&client->mutex);
return -ENOMEM;
}
nfs_set_events(client);
qemu_mutex_unlock(&client->mutex);
while (!task.complete) {
qemu_coroutine_yield();
}
if (task.ret < 0) {
return task.ret;
}
/* zero pad short reads */
if (task.ret < iov->size) {
qemu_iovec_memset(iov, task.ret, 0, iov->size - task.ret);
}
return 0;
}
static int coroutine_fn nfs_co_pwritev(BlockDriverState *bs, uint64_t offset,
uint64_t bytes, QEMUIOVector *iov,
int flags)
{
NFSClient *client = bs->opaque;
NFSRPC task;
char *buf = NULL;
bool my_buffer = false;
nfs_co_init_task(bs, &task);
if (iov->niov != 1) {
buf = g_try_malloc(bytes);
if (bytes && buf == NULL) {
return -ENOMEM;
}
qemu_iovec_to_buf(iov, 0, buf, bytes);
my_buffer = true;
} else {
buf = iov->iov[0].iov_base;
}
qemu_mutex_lock(&client->mutex);
if (nfs_pwrite_async(client->context, client->fh,
offset, bytes, buf,
nfs_co_generic_cb, &task) != 0) {
qemu_mutex_unlock(&client->mutex);
if (my_buffer) {
g_free(buf);
}
return -ENOMEM;
}
nfs_set_events(client);
qemu_mutex_unlock(&client->mutex);
while (!task.complete) {
qemu_coroutine_yield();
}
if (my_buffer) {
g_free(buf);
}
if (task.ret != bytes) {
return task.ret < 0 ? task.ret : -EIO;
}
return 0;
}
static int coroutine_fn nfs_co_flush(BlockDriverState *bs)
{
NFSClient *client = bs->opaque;
NFSRPC task;
nfs_co_init_task(bs, &task);
qemu_mutex_lock(&client->mutex);
if (nfs_fsync_async(client->context, client->fh, nfs_co_generic_cb,
&task) != 0) {
qemu_mutex_unlock(&client->mutex);
return -ENOMEM;
}
nfs_set_events(client);
qemu_mutex_unlock(&client->mutex);
while (!task.complete) {
qemu_coroutine_yield();
}
return task.ret;
}
static QemuOptsList runtime_opts = {
.name = "nfs",
.head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
.desc = {
{
.name = "path",
.type = QEMU_OPT_STRING,
.help = "Path of the image on the host",
},
{
.name = "user",
.type = QEMU_OPT_NUMBER,
.help = "UID value to use when talking to the server",
},
{
.name = "group",
.type = QEMU_OPT_NUMBER,
.help = "GID value to use when talking to the server",
},
{
.name = "tcp-syn-count",
.type = QEMU_OPT_NUMBER,
.help = "Number of SYNs to send during the session establish",
},
{
.name = "readahead-size",
.type = QEMU_OPT_NUMBER,
.help = "Set the readahead size in bytes",
},
{
.name = "page-cache-size",
.type = QEMU_OPT_NUMBER,
.help = "Set the pagecache size in bytes",
},
{
.name = "debug",
.type = QEMU_OPT_NUMBER,
.help = "Set the NFS debug level (max 2)",
},
{ /* end of list */ }
},
};
static void nfs_detach_aio_context(BlockDriverState *bs)
{
NFSClient *client = bs->opaque;
aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
false, NULL, NULL, NULL, NULL);
client->events = 0;
}
static void nfs_attach_aio_context(BlockDriverState *bs,
AioContext *new_context)
{
NFSClient *client = bs->opaque;
client->aio_context = new_context;
nfs_set_events(client);
}
static void nfs_client_close(NFSClient *client)
{
if (client->context) {
if (client->fh) {
nfs_close(client->context, client->fh);
}
aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
false, NULL, NULL, NULL, NULL);
nfs_destroy_context(client->context);
}
memset(client, 0, sizeof(NFSClient));
}
static void nfs_file_close(BlockDriverState *bs)
{
NFSClient *client = bs->opaque;
nfs_client_close(client);
qemu_mutex_destroy(&client->mutex);
}
static NFSServer *nfs_config(QDict *options, Error **errp)
{
NFSServer *server = NULL;
QDict *addr = NULL;
QObject *crumpled_addr = NULL;
Visitor *iv = NULL;
Error *local_error = NULL;
qdict_extract_subqdict(options, &addr, "server.");
if (!qdict_size(addr)) {
error_setg(errp, "NFS server address missing");
goto out;
}
crumpled_addr = qdict_crumple(addr, errp);
if (!crumpled_addr) {
goto out;
}
/*
* Caution: this works only because all scalar members of
* NFSServer are QString in @crumpled_addr. The visitor expects
* @crumpled_addr to be typed according to the QAPI schema. It
* is when @options come from -blockdev or blockdev_add. But when
* they come from -drive, they're all QString.
*/
iv = qobject_input_visitor_new(crumpled_addr);
visit_type_NFSServer(iv, NULL, &server, &local_error);
if (local_error) {
error_propagate(errp, local_error);
goto out;
}
out:
QDECREF(addr);
qobject_decref(crumpled_addr);
visit_free(iv);
return server;
}
static int64_t nfs_client_open(NFSClient *client, QDict *options,
int flags, Error **errp, int open_flags)
{
int ret = -EINVAL;
QemuOpts *opts = NULL;
Error *local_err = NULL;
struct stat st;
char *file = NULL, *strp = NULL;
opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
if (local_err) {
error_propagate(errp, local_err);
ret = -EINVAL;
goto fail;
}
client->path = g_strdup(qemu_opt_get(opts, "path"));
if (!client->path) {
ret = -EINVAL;
error_setg(errp, "No path was specified");
goto fail;
}
strp = strrchr(client->path, '/');
if (strp == NULL) {
error_setg(errp, "Invalid URL specified");
goto fail;
}
file = g_strdup(strp);
*strp = 0;
/* Pop the config into our state object, Exit if invalid */
client->server = nfs_config(options, errp);
if (!client->server) {
ret = -EINVAL;
goto fail;
}
client->context = nfs_init_context();
if (client->context == NULL) {
error_setg(errp, "Failed to init NFS context");
goto fail;
}
if (qemu_opt_get(opts, "user")) {
client->uid = qemu_opt_get_number(opts, "user", 0);
nfs_set_uid(client->context, client->uid);
}
if (qemu_opt_get(opts, "group")) {
client->gid = qemu_opt_get_number(opts, "group", 0);
nfs_set_gid(client->context, client->gid);
}
if (qemu_opt_get(opts, "tcp-syn-count")) {
client->tcp_syncnt = qemu_opt_get_number(opts, "tcp-syn-count", 0);
nfs_set_tcp_syncnt(client->context, client->tcp_syncnt);
}
#ifdef LIBNFS_FEATURE_READAHEAD
if (qemu_opt_get(opts, "readahead-size")) {
if (open_flags & BDRV_O_NOCACHE) {
error_setg(errp, "Cannot enable NFS readahead "
"if cache.direct = on");
goto fail;
}
client->readahead = qemu_opt_get_number(opts, "readahead-size", 0);
if (client->readahead > QEMU_NFS_MAX_READAHEAD_SIZE) {
error_report("NFS Warning: Truncating NFS readahead "
"size to %d", QEMU_NFS_MAX_READAHEAD_SIZE);
client->readahead = QEMU_NFS_MAX_READAHEAD_SIZE;
}
nfs_set_readahead(client->context, client->readahead);
#ifdef LIBNFS_FEATURE_PAGECACHE
nfs_set_pagecache_ttl(client->context, 0);
#endif
client->cache_used = true;
}
#endif
#ifdef LIBNFS_FEATURE_PAGECACHE
if (qemu_opt_get(opts, "page-cache-size")) {
if (open_flags & BDRV_O_NOCACHE) {
error_setg(errp, "Cannot enable NFS pagecache "
"if cache.direct = on");
goto fail;
}
client->pagecache = qemu_opt_get_number(opts, "page-cache-size", 0);
if (client->pagecache > QEMU_NFS_MAX_PAGECACHE_SIZE) {
error_report("NFS Warning: Truncating NFS pagecache "
"size to %d pages", QEMU_NFS_MAX_PAGECACHE_SIZE);
client->pagecache = QEMU_NFS_MAX_PAGECACHE_SIZE;
}
nfs_set_pagecache(client->context, client->pagecache);
nfs_set_pagecache_ttl(client->context, 0);
client->cache_used = true;
}
#endif
#ifdef LIBNFS_FEATURE_DEBUG
if (qemu_opt_get(opts, "debug")) {
client->debug = qemu_opt_get_number(opts, "debug", 0);
/* limit the maximum debug level to avoid potential flooding
* of our log files. */
if (client->debug > QEMU_NFS_MAX_DEBUG_LEVEL) {
error_report("NFS Warning: Limiting NFS debug level "
"to %d", QEMU_NFS_MAX_DEBUG_LEVEL);
client->debug = QEMU_NFS_MAX_DEBUG_LEVEL;
}
nfs_set_debug(client->context, client->debug);
}
#endif
ret = nfs_mount(client->context, client->server->host, client->path);
if (ret < 0) {
error_setg(errp, "Failed to mount nfs share: %s",
nfs_get_error(client->context));
goto fail;
}
if (flags & O_CREAT) {
ret = nfs_creat(client->context, file, 0600, &client->fh);
if (ret < 0) {
error_setg(errp, "Failed to create file: %s",
nfs_get_error(client->context));
goto fail;
}
} else {
ret = nfs_open(client->context, file, flags, &client->fh);
if (ret < 0) {
error_setg(errp, "Failed to open file : %s",
nfs_get_error(client->context));
goto fail;
}
}
ret = nfs_fstat(client->context, client->fh, &st);
if (ret < 0) {
error_setg(errp, "Failed to fstat file: %s",
nfs_get_error(client->context));
goto fail;
}
ret = DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE);
client->st_blocks = st.st_blocks;
client->has_zero_init = S_ISREG(st.st_mode);
*strp = '/';
goto out;
fail:
nfs_client_close(client);
out:
qemu_opts_del(opts);
g_free(file);
return ret;
}
static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp) {
NFSClient *client = bs->opaque;
int64_t ret;
client->aio_context = bdrv_get_aio_context(bs);
ret = nfs_client_open(client, options,
(flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY,
errp, bs->open_flags);
if (ret < 0) {
return ret;
}
qemu_mutex_init(&client->mutex);
bs->total_sectors = ret;
ret = 0;
return ret;
}
static QemuOptsList nfs_create_opts = {
.name = "nfs-create-opts",
.head = QTAILQ_HEAD_INITIALIZER(nfs_create_opts.head),
.desc = {
{
.name = BLOCK_OPT_SIZE,
.type = QEMU_OPT_SIZE,
.help = "Virtual disk size"
},
{ /* end of list */ }
}
};
static int nfs_file_create(const char *url, QemuOpts *opts, Error **errp)
{
int ret = 0;
int64_t total_size = 0;
NFSClient *client = g_new0(NFSClient, 1);
QDict *options = NULL;
client->aio_context = qemu_get_aio_context();
/* Read out options */
total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
BDRV_SECTOR_SIZE);
options = qdict_new();
ret = nfs_parse_uri(url, options, errp);
if (ret < 0) {
goto out;
}
ret = nfs_client_open(client, options, O_CREAT, errp, 0);
if (ret < 0) {
goto out;
}
ret = nfs_ftruncate(client->context, client->fh, total_size);
nfs_client_close(client);
out:
QDECREF(options);
g_free(client);
return ret;
}
static int nfs_has_zero_init(BlockDriverState *bs)
{
NFSClient *client = bs->opaque;
return client->has_zero_init;
}
/* Called (via nfs_service) with QemuMutex held. */
static void
nfs_get_allocated_file_size_cb(int ret, struct nfs_context *nfs, void *data,
void *private_data)
{
NFSRPC *task = private_data;
task->ret = ret;
if (task->ret == 0) {
memcpy(task->st, data, sizeof(struct stat));
}
if (task->ret < 0) {
error_report("NFS Error: %s", nfs_get_error(nfs));
}
task->complete = 1;
bdrv_wakeup(task->bs);
}
static int64_t nfs_get_allocated_file_size(BlockDriverState *bs)
{
NFSClient *client = bs->opaque;
NFSRPC task = {0};
struct stat st;
if (bdrv_is_read_only(bs) &&
!(bs->open_flags & BDRV_O_NOCACHE)) {
return client->st_blocks * 512;
}
task.bs = bs;
task.st = &st;
if (nfs_fstat_async(client->context, client->fh, nfs_get_allocated_file_size_cb,
&task) != 0) {
return -ENOMEM;
}
nfs_set_events(client);
BDRV_POLL_WHILE(bs, !task.complete);
return (task.ret < 0 ? task.ret : st.st_blocks * 512);
}
static int nfs_file_truncate(BlockDriverState *bs, int64_t offset)
{
NFSClient *client = bs->opaque;
return nfs_ftruncate(client->context, client->fh, offset);
}
/* Note that this will not re-establish a connection with the NFS server
* - it is effectively a NOP. */
static int nfs_reopen_prepare(BDRVReopenState *state,
BlockReopenQueue *queue, Error **errp)
{
NFSClient *client = state->bs->opaque;
struct stat st;
int ret = 0;
if (state->flags & BDRV_O_RDWR && bdrv_is_read_only(state->bs)) {
error_setg(errp, "Cannot open a read-only mount as read-write");
return -EACCES;
}
if ((state->flags & BDRV_O_NOCACHE) && client->cache_used) {
error_setg(errp, "Cannot disable cache if libnfs readahead or"
" pagecache is enabled");
return -EINVAL;
}
/* Update cache for read-only reopens */
if (!(state->flags & BDRV_O_RDWR)) {
ret = nfs_fstat(client->context, client->fh, &st);
if (ret < 0) {
error_setg(errp, "Failed to fstat file: %s",
nfs_get_error(client->context));
return ret;
}
client->st_blocks = st.st_blocks;
}
return 0;
}
static void nfs_refresh_filename(BlockDriverState *bs, QDict *options)
{
NFSClient *client = bs->opaque;
QDict *opts = qdict_new();
QObject *server_qdict;
Visitor *ov;
qdict_put(opts, "driver", qstring_from_str("nfs"));
if (client->uid && !client->gid) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nfs://%s%s?uid=%" PRId64, client->server->host, client->path,
client->uid);
} else if (!client->uid && client->gid) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nfs://%s%s?gid=%" PRId64, client->server->host, client->path,
client->gid);
} else if (client->uid && client->gid) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nfs://%s%s?uid=%" PRId64 "&gid=%" PRId64,
client->server->host, client->path, client->uid, client->gid);
} else {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nfs://%s%s", client->server->host, client->path);
}
ov = qobject_output_visitor_new(&server_qdict);
visit_type_NFSServer(ov, NULL, &client->server, &error_abort);
visit_complete(ov, &server_qdict);
qdict_put_obj(opts, "server", server_qdict);
qdict_put(opts, "path", qstring_from_str(client->path));
if (client->uid) {
qdict_put(opts, "user", qint_from_int(client->uid));
}
if (client->gid) {
qdict_put(opts, "group", qint_from_int(client->gid));
}
if (client->tcp_syncnt) {
qdict_put(opts, "tcp-syn-cnt",
qint_from_int(client->tcp_syncnt));
}
if (client->readahead) {
qdict_put(opts, "readahead-size",
qint_from_int(client->readahead));
}
if (client->pagecache) {
qdict_put(opts, "page-cache-size",
qint_from_int(client->pagecache));
}
if (client->debug) {
qdict_put(opts, "debug", qint_from_int(client->debug));
}
visit_free(ov);
qdict_flatten(opts);
bs->full_open_options = opts;
}
#ifdef LIBNFS_FEATURE_PAGECACHE
static void nfs_invalidate_cache(BlockDriverState *bs,
Error **errp)
{
NFSClient *client = bs->opaque;
nfs_pagecache_invalidate(client->context, client->fh);
}
#endif
static BlockDriver bdrv_nfs = {
.format_name = "nfs",
.protocol_name = "nfs",
.instance_size = sizeof(NFSClient),
.bdrv_parse_filename = nfs_parse_filename,
.create_opts = &nfs_create_opts,
.bdrv_has_zero_init = nfs_has_zero_init,
.bdrv_get_allocated_file_size = nfs_get_allocated_file_size,
.bdrv_truncate = nfs_file_truncate,
.bdrv_file_open = nfs_file_open,
.bdrv_close = nfs_file_close,
.bdrv_create = nfs_file_create,
.bdrv_reopen_prepare = nfs_reopen_prepare,
.bdrv_co_preadv = nfs_co_preadv,
.bdrv_co_pwritev = nfs_co_pwritev,
.bdrv_co_flush_to_disk = nfs_co_flush,
.bdrv_detach_aio_context = nfs_detach_aio_context,
.bdrv_attach_aio_context = nfs_attach_aio_context,
.bdrv_refresh_filename = nfs_refresh_filename,
#ifdef LIBNFS_FEATURE_PAGECACHE
.bdrv_invalidate_cache = nfs_invalidate_cache,
#endif
};
static void nfs_block_init(void)
{
bdrv_register(&bdrv_nfs);
}
block_init(nfs_block_init);
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