};
struct NBDExport {
+ int refcount;
+ void (*close)(NBDExport *exp);
+
BlockDriverState *bs;
+ char *name;
off_t dev_offset;
off_t size;
uint32_t nbdflags;
+ QTAILQ_HEAD(, NBDClient) clients;
QSIMPLEQ_HEAD(, NBDRequest) requests;
+ QTAILQ_ENTRY(NBDExport) next;
};
+static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports);
+
struct NBDClient {
int refcount;
void (*close)(NBDClient *client);
CoMutex send_lock;
Coroutine *send_coroutine;
+ QTAILQ_ENTRY(NBDClient) next;
int nb_requests;
bool closing;
};
int tcp_socket_outgoing_spec(const char *address_and_port)
{
- return inet_connect(address_and_port, true, NULL, NULL);
+ Error *local_err = NULL;
+ int fd = inet_connect(address_and_port, &local_err);
+
+ if (local_err != NULL) {
+ qerror_report_err(local_err);
+ error_free(local_err);
+ }
+ return fd;
}
int tcp_socket_incoming(const char *address, uint16_t port)
int tcp_socket_incoming_spec(const char *address_and_port)
{
- char *ostr = NULL;
- int olen = 0;
- return inet_listen(address_and_port, ostr, olen, SOCK_STREAM, 0, NULL);
+ Error *local_err = NULL;
+ int fd = inet_listen(address_and_port, NULL, 0, SOCK_STREAM, 0, &local_err);
+
+ if (local_err != NULL) {
+ qerror_report_err(local_err);
+ error_free(local_err);
+ }
+ return fd;
}
int unix_socket_incoming(const char *path)
{
- char *ostr = NULL;
- int olen = 0;
+ Error *local_err = NULL;
+ int fd = unix_listen(path, NULL, 0, &local_err);
- return unix_listen(path, ostr, olen);
+ if (local_err != NULL) {
+ qerror_report_err(local_err);
+ error_free(local_err);
+ }
+ return fd;
}
int unix_socket_outgoing(const char *path)
{
- return unix_connect(path);
+ Error *local_err = NULL;
+ int fd = unix_connect(path, &local_err);
+
+ if (local_err != NULL) {
+ qerror_report_err(local_err);
+ error_free(local_err);
+ }
+ return fd;
}
-/* Basic flow
+/* Basic flow for negotiation
Server Client
-
Negotiate
+
+ or
+
+ Server Client
+ Negotiate #1
+ Option
+ Negotiate #2
+
+ ----
+
+ followed by
+
+ Server Client
Request
Response
Request
...
...
Request (type == 2)
+
*/
+static int nbd_receive_options(NBDClient *client)
+{
+ int csock = client->sock;
+ char name[256];
+ uint32_t tmp, length;
+ uint64_t magic;
+ int rc;
+
+ /* Client sends:
+ [ 0 .. 3] reserved (0)
+ [ 4 .. 11] NBD_OPTS_MAGIC
+ [12 .. 15] NBD_OPT_EXPORT_NAME
+ [16 .. 19] length
+ [20 .. xx] export name (length bytes)
+ */
+
+ rc = -EINVAL;
+ if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
+ LOG("read failed");
+ goto fail;
+ }
+ TRACE("Checking reserved");
+ if (tmp != 0) {
+ LOG("Bad reserved received");
+ goto fail;
+ }
+
+ if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
+ LOG("read failed");
+ goto fail;
+ }
+ TRACE("Checking reserved");
+ if (magic != be64_to_cpu(NBD_OPTS_MAGIC)) {
+ LOG("Bad magic received");
+ goto fail;
+ }
+
+ if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
+ LOG("read failed");
+ goto fail;
+ }
+ TRACE("Checking option");
+ if (tmp != be32_to_cpu(NBD_OPT_EXPORT_NAME)) {
+ LOG("Bad option received");
+ goto fail;
+ }
+
+ if (read_sync(csock, &length, sizeof(length)) != sizeof(length)) {
+ LOG("read failed");
+ goto fail;
+ }
+ TRACE("Checking length");
+ length = be32_to_cpu(length);
+ if (length > 255) {
+ LOG("Bad length received");
+ goto fail;
+ }
+ if (read_sync(csock, name, length) != length) {
+ LOG("read failed");
+ goto fail;
+ }
+ name[length] = '\0';
+
+ client->exp = nbd_export_find(name);
+ if (!client->exp) {
+ LOG("export not found");
+ goto fail;
+ }
+
+ QTAILQ_INSERT_TAIL(&client->exp->clients, client, next);
+ nbd_export_get(client->exp);
+
+ TRACE("Option negotiation succeeded.");
+ rc = 0;
+fail:
+ return rc;
+}
+
static int nbd_send_negotiate(NBDClient *client)
{
int csock = client->sock;
char buf[8 + 8 + 8 + 128];
int rc;
+ const int myflags = (NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_TRIM |
+ NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA);
- /* Negotiate
- [ 0 .. 7] passwd ("NBDMAGIC")
- [ 8 .. 15] magic (NBD_CLIENT_MAGIC)
+ /* Negotiation header without options:
+ [ 0 .. 7] passwd ("NBDMAGIC")
+ [ 8 .. 15] magic (NBD_CLIENT_MAGIC)
[16 .. 23] size
- [24 .. 27] flags
- [28 .. 151] reserved (0)
+ [24 .. 25] server flags (0)
+ [24 .. 27] export flags
+ [28 .. 151] reserved (0)
+
+ Negotiation header with options, part 1:
+ [ 0 .. 7] passwd ("NBDMAGIC")
+ [ 8 .. 15] magic (NBD_OPTS_MAGIC)
+ [16 .. 17] server flags (0)
+
+ part 2 (after options are sent):
+ [18 .. 25] size
+ [26 .. 27] export flags
+ [28 .. 151] reserved (0)
*/
socket_set_block(csock);
rc = -EINVAL;
TRACE("Beginning negotiation.");
+ memset(buf, 0, sizeof(buf));
memcpy(buf, "NBDMAGIC", 8);
- cpu_to_be64w((uint64_t*)(buf + 8), NBD_CLIENT_MAGIC);
- cpu_to_be64w((uint64_t*)(buf + 16), client->exp->size);
- cpu_to_be32w((uint32_t*)(buf + 24),
- client->exp->nbdflags | NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_TRIM |
- NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA);
- memset(buf + 28, 0, 124);
-
- if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
- LOG("write failed");
- goto fail;
+ if (client->exp) {
+ assert ((client->exp->nbdflags & ~65535) == 0);
+ cpu_to_be64w((uint64_t*)(buf + 8), NBD_CLIENT_MAGIC);
+ cpu_to_be64w((uint64_t*)(buf + 16), client->exp->size);
+ cpu_to_be16w((uint16_t*)(buf + 26), client->exp->nbdflags | myflags);
+ } else {
+ cpu_to_be64w((uint64_t*)(buf + 8), NBD_OPTS_MAGIC);
+ }
+
+ if (client->exp) {
+ if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
+ LOG("write failed");
+ goto fail;
+ }
+ } else {
+ if (write_sync(csock, buf, 18) != 18) {
+ LOG("write failed");
+ goto fail;
+ }
+ rc = nbd_receive_options(client);
+ if (rc < 0) {
+ LOG("option negotiation failed");
+ goto fail;
+ }
+
+ assert ((client->exp->nbdflags & ~65535) == 0);
+ cpu_to_be64w((uint64_t*)(buf + 18), client->exp->size);
+ cpu_to_be16w((uint16_t*)(buf + 26), client->exp->nbdflags | myflags);
+ if (write_sync(csock, buf + 18, sizeof(buf) - 18) != sizeof(buf) - 18) {
+ LOG("write failed");
+ goto fail;
+ }
}
TRACE("Negotiation succeeded.");
return -serrno;
}
- if (flags & NBD_FLAG_READ_ONLY) {
- int read_only = 1;
- TRACE("Setting readonly attribute");
+ if (ioctl(fd, NBD_SET_FLAGS, flags) < 0) {
+ if (errno == ENOTTY) {
+ int read_only = (flags & NBD_FLAG_READ_ONLY) != 0;
+ TRACE("Setting readonly attribute");
- if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
+ if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
+ int serrno = errno;
+ LOG("Failed setting read-only attribute");
+ return -serrno;
+ }
+ } else {
int serrno = errno;
- LOG("Failed setting read-only attribute");
+ LOG("Failed setting flags");
return -serrno;
}
}
- if (ioctl(fd, NBD_SET_FLAGS, flags) < 0
- && errno != ENOTTY) {
- int serrno = errno;
- LOG("Failed setting flags");
- return -serrno;
- }
-
TRACE("Negotiation ended");
return 0;
qemu_set_fd_handler2(client->sock, NULL, NULL, NULL, NULL);
close(client->sock);
client->sock = -1;
+ if (client->exp) {
+ QTAILQ_REMOVE(&client->exp->clients, client, next);
+ nbd_export_put(client->exp);
+ }
g_free(client);
}
}
}
NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset,
- off_t size, uint32_t nbdflags)
+ off_t size, uint32_t nbdflags,
+ void (*close)(NBDExport *))
{
NBDExport *exp = g_malloc0(sizeof(NBDExport));
QSIMPLEQ_INIT(&exp->requests);
+ exp->refcount = 1;
+ QTAILQ_INIT(&exp->clients);
exp->bs = bs;
exp->dev_offset = dev_offset;
exp->nbdflags = nbdflags;
exp->size = size == -1 ? bdrv_getlength(bs) : size;
+ exp->close = close;
return exp;
}
+NBDExport *nbd_export_find(const char *name)
+{
+ NBDExport *exp;
+ QTAILQ_FOREACH(exp, &exports, next) {
+ if (strcmp(name, exp->name) == 0) {
+ return exp;
+ }
+ }
+
+ return NULL;
+}
+
+void nbd_export_set_name(NBDExport *exp, const char *name)
+{
+ if (exp->name == name) {
+ return;
+ }
+
+ nbd_export_get(exp);
+ if (exp->name != NULL) {
+ g_free(exp->name);
+ exp->name = NULL;
+ QTAILQ_REMOVE(&exports, exp, next);
+ nbd_export_put(exp);
+ }
+ if (name != NULL) {
+ nbd_export_get(exp);
+ exp->name = g_strdup(name);
+ QTAILQ_INSERT_TAIL(&exports, exp, next);
+ }
+ nbd_export_put(exp);
+}
+
void nbd_export_close(NBDExport *exp)
{
- while (!QSIMPLEQ_EMPTY(&exp->requests)) {
- NBDRequest *first = QSIMPLEQ_FIRST(&exp->requests);
- QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry);
- qemu_vfree(first->data);
- g_free(first);
+ NBDClient *client, *next;
+
+ nbd_export_get(exp);
+ QTAILQ_FOREACH_SAFE(client, &exp->clients, next, next) {
+ nbd_client_close(client);
}
+ nbd_export_set_name(exp, NULL);
+ nbd_export_put(exp);
+}
- g_free(exp);
+void nbd_export_get(NBDExport *exp)
+{
+ assert(exp->refcount > 0);
+ exp->refcount++;
+}
+
+void nbd_export_put(NBDExport *exp)
+{
+ assert(exp->refcount > 0);
+ if (exp->refcount == 1) {
+ nbd_export_close(exp);
+ }
+
+ if (--exp->refcount == 0) {
+ assert(exp->name == NULL);
+
+ if (exp->close) {
+ exp->close(exp);
+ }
+
+ while (!QSIMPLEQ_EMPTY(&exp->requests)) {
+ NBDRequest *first = QSIMPLEQ_FIRST(&exp->requests);
+ QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry);
+ qemu_vfree(first->data);
+ g_free(first);
+ }
+
+ g_free(exp);
+ }
+}
+
+BlockDriverState *nbd_export_get_blockdev(NBDExport *exp)
+{
+ return exp->bs;
+}
+
+void nbd_export_close_all(void)
+{
+ NBDExport *exp, *next;
+
+ QTAILQ_FOREACH_SAFE(exp, &exports, next, next) {
+ nbd_export_close(exp);
+ }
}
static int nbd_can_read(void *opaque);
client->close = close;
qemu_co_mutex_init(&client->send_lock);
qemu_set_fd_handler2(csock, nbd_can_read, nbd_read, NULL, client);
+
+ if (exp) {
+ QTAILQ_INSERT_TAIL(&exp->clients, client, next);
+ nbd_export_get(exp);
+ }
return client;
}
projects / qemu.git / blobdiff