diff options
| -rw-r--r-- | nbd/server.c | 150 |
1 files changed, 103 insertions, 47 deletions
diff --git a/nbd/server.c b/nbd/server.c index ba25ce3604..8752885509 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -93,13 +93,45 @@ static void nbd_set_handlers(NBDClient *client); static void nbd_unset_handlers(NBDClient *client); static void nbd_update_can_read(NBDClient *client); -static ssize_t drop_sync(int fd, size_t size) +static void nbd_negotiate_continue(void *opaque) +{ + qemu_coroutine_enter(opaque, NULL); +} + +static ssize_t nbd_negotiate_read(int fd, void *buffer, size_t size) +{ + ssize_t ret; + + assert(qemu_in_coroutine()); + /* Negotiation are always in main loop. */ + qemu_set_fd_handler(fd, nbd_negotiate_continue, NULL, + qemu_coroutine_self()); + ret = read_sync(fd, buffer, size); + qemu_set_fd_handler(fd, NULL, NULL, NULL); + return ret; + +} + +static ssize_t nbd_negotiate_write(int fd, void *buffer, size_t size) +{ + ssize_t ret; + + assert(qemu_in_coroutine()); + /* Negotiation are always in main loop. */ + qemu_set_fd_handler(fd, NULL, nbd_negotiate_continue, + qemu_coroutine_self()); + ret = write_sync(fd, buffer, size); + qemu_set_fd_handler(fd, NULL, NULL, NULL); + return ret; +} + +static ssize_t nbd_negotiate_drop_sync(int fd, size_t size) { ssize_t ret, dropped = size; uint8_t *buffer = g_malloc(MIN(65536, size)); while (size > 0) { - ret = read_sync(fd, buffer, MIN(65536, size)); + ret = nbd_negotiate_read(fd, buffer, MIN(65536, size)); if (ret < 0) { g_free(buffer); return ret; @@ -140,96 +172,96 @@ static ssize_t drop_sync(int fd, size_t size) */ -static int nbd_send_rep(int csock, uint32_t type, uint32_t opt) +static int nbd_negotiate_send_rep(int csock, uint32_t type, uint32_t opt) { uint64_t magic; uint32_t len; magic = cpu_to_be64(NBD_REP_MAGIC); - if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { + if (nbd_negotiate_write(csock, &magic, sizeof(magic)) != sizeof(magic)) { LOG("write failed (rep magic)"); return -EINVAL; } opt = cpu_to_be32(opt); - if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { + if (nbd_negotiate_write(csock, &opt, sizeof(opt)) != sizeof(opt)) { LOG("write failed (rep opt)"); return -EINVAL; } type = cpu_to_be32(type); - if (write_sync(csock, &type, sizeof(type)) != sizeof(type)) { + if (nbd_negotiate_write(csock, &type, sizeof(type)) != sizeof(type)) { LOG("write failed (rep type)"); return -EINVAL; } len = cpu_to_be32(0); - if (write_sync(csock, &len, sizeof(len)) != sizeof(len)) { + if (nbd_negotiate_write(csock, &len, sizeof(len)) != sizeof(len)) { LOG("write failed (rep data length)"); return -EINVAL; } return 0; } -static int nbd_send_rep_list(int csock, NBDExport *exp) +static int nbd_negotiate_send_rep_list(int csock, NBDExport *exp) { uint64_t magic, name_len; uint32_t opt, type, len; name_len = strlen(exp->name); magic = cpu_to_be64(NBD_REP_MAGIC); - if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { + if (nbd_negotiate_write(csock, &magic, sizeof(magic)) != sizeof(magic)) { LOG("write failed (magic)"); return -EINVAL; } opt = cpu_to_be32(NBD_OPT_LIST); - if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { + if (nbd_negotiate_write(csock, &opt, sizeof(opt)) != sizeof(opt)) { LOG("write failed (opt)"); return -EINVAL; } type = cpu_to_be32(NBD_REP_SERVER); - if (write_sync(csock, &type, sizeof(type)) != sizeof(type)) { + if (nbd_negotiate_write(csock, &type, sizeof(type)) != sizeof(type)) { LOG("write failed (reply type)"); return -EINVAL; } len = cpu_to_be32(name_len + sizeof(len)); - if (write_sync(csock, &len, sizeof(len)) != sizeof(len)) { + if (nbd_negotiate_write(csock, &len, sizeof(len)) != sizeof(len)) { LOG("write failed (length)"); return -EINVAL; } len = cpu_to_be32(name_len); - if (write_sync(csock, &len, sizeof(len)) != sizeof(len)) { + if (nbd_negotiate_write(csock, &len, sizeof(len)) != sizeof(len)) { LOG("write failed (length)"); return -EINVAL; } - if (write_sync(csock, exp->name, name_len) != name_len) { + if (nbd_negotiate_write(csock, exp->name, name_len) != name_len) { LOG("write failed (buffer)"); return -EINVAL; } return 0; } -static int nbd_handle_list(NBDClient *client, uint32_t length) +static int nbd_negotiate_handle_list(NBDClient *client, uint32_t length) { int csock; NBDExport *exp; csock = client->sock; if (length) { - if (drop_sync(csock, length) != length) { + if (nbd_negotiate_drop_sync(csock, length) != length) { return -EIO; } - return nbd_send_rep(csock, NBD_REP_ERR_INVALID, NBD_OPT_LIST); + return nbd_negotiate_send_rep(csock, NBD_REP_ERR_INVALID, NBD_OPT_LIST); } /* For each export, send a NBD_REP_SERVER reply. */ QTAILQ_FOREACH(exp, &exports, next) { - if (nbd_send_rep_list(csock, exp)) { + if (nbd_negotiate_send_rep_list(csock, exp)) { return -EINVAL; } } /* Finish with a NBD_REP_ACK. */ - return nbd_send_rep(csock, NBD_REP_ACK, NBD_OPT_LIST); + return nbd_negotiate_send_rep(csock, NBD_REP_ACK, NBD_OPT_LIST); } -static int nbd_handle_export_name(NBDClient *client, uint32_t length) +static int nbd_negotiate_handle_export_name(NBDClient *client, uint32_t length) { int rc = -EINVAL, csock = client->sock; char name[256]; @@ -242,7 +274,7 @@ static int nbd_handle_export_name(NBDClient *client, uint32_t length) LOG("Bad length received"); goto fail; } - if (read_sync(csock, name, length) != length) { + if (nbd_negotiate_read(csock, name, length) != length) { LOG("read failed"); goto fail; } @@ -261,7 +293,7 @@ fail: return rc; } -static int nbd_receive_options(NBDClient *client) +static int nbd_negotiate_options(NBDClient *client) { int csock = client->sock; uint32_t flags; @@ -280,7 +312,7 @@ static int nbd_receive_options(NBDClient *client) ... Rest of request */ - if (read_sync(csock, &flags, sizeof(flags)) != sizeof(flags)) { + if (nbd_negotiate_read(csock, &flags, sizeof(flags)) != sizeof(flags)) { LOG("read failed"); return -EIO; } @@ -296,7 +328,7 @@ static int nbd_receive_options(NBDClient *client) uint32_t tmp, length; uint64_t magic; - if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { + if (nbd_negotiate_read(csock, &magic, sizeof(magic)) != sizeof(magic)) { LOG("read failed"); return -EINVAL; } @@ -306,12 +338,13 @@ static int nbd_receive_options(NBDClient *client) return -EINVAL; } - if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { + if (nbd_negotiate_read(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { LOG("read failed"); return -EINVAL; } - if (read_sync(csock, &length, sizeof(length)) != sizeof(length)) { + if (nbd_negotiate_read(csock, &length, + sizeof(length)) != sizeof(length)) { LOG("read failed"); return -EINVAL; } @@ -320,7 +353,7 @@ static int nbd_receive_options(NBDClient *client) TRACE("Checking option"); switch (be32_to_cpu(tmp)) { case NBD_OPT_LIST: - ret = nbd_handle_list(client, length); + ret = nbd_negotiate_handle_list(client, length); if (ret < 0) { return ret; } @@ -330,19 +363,25 @@ static int nbd_receive_options(NBDClient *client) return -EINVAL; case NBD_OPT_EXPORT_NAME: - return nbd_handle_export_name(client, length); + return nbd_negotiate_handle_export_name(client, length); default: tmp = be32_to_cpu(tmp); LOG("Unsupported option 0x%x", tmp); - nbd_send_rep(client->sock, NBD_REP_ERR_UNSUP, tmp); + nbd_negotiate_send_rep(client->sock, NBD_REP_ERR_UNSUP, tmp); return -EINVAL; } } } -static int nbd_send_negotiate(NBDClient *client) +typedef struct { + NBDClient *client; + Coroutine *co; +} NBDClientNewData; + +static coroutine_fn int nbd_negotiate(NBDClientNewData *data) { + NBDClient *client = data->client; int csock = client->sock; char buf[8 + 8 + 8 + 128]; int rc; @@ -368,7 +407,6 @@ static int nbd_send_negotiate(NBDClient *client) [28 .. 151] reserved (0) */ - qemu_set_block(csock); rc = -EINVAL; TRACE("Beginning negotiation."); @@ -385,16 +423,16 @@ static int nbd_send_negotiate(NBDClient *client) } if (client->exp) { - if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { + if (nbd_negotiate_write(csock, buf, sizeof(buf)) != sizeof(buf)) { LOG("write failed"); goto fail; } } else { - if (write_sync(csock, buf, 18) != 18) { + if (nbd_negotiate_write(csock, buf, 18) != 18) { LOG("write failed"); goto fail; } - rc = nbd_receive_options(client); + rc = nbd_negotiate_options(client); if (rc != 0) { LOG("option negotiation failed"); goto fail; @@ -403,7 +441,8 @@ static int nbd_send_negotiate(NBDClient *client) 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) { + if (nbd_negotiate_write(csock, buf + 18, + sizeof(buf) - 18) != sizeof(buf) - 18) { LOG("write failed"); goto fail; } @@ -412,7 +451,6 @@ static int nbd_send_negotiate(NBDClient *client) TRACE("Negotiation succeeded."); rc = 0; fail: - qemu_set_nonblock(csock); return rc; } @@ -1028,25 +1066,43 @@ static void nbd_update_can_read(NBDClient *client) } } +static coroutine_fn void nbd_co_client_start(void *opaque) +{ + NBDClientNewData *data = opaque; + NBDClient *client = data->client; + NBDExport *exp = client->exp; + + if (exp) { + nbd_export_get(exp); + } + if (nbd_negotiate(data)) { + shutdown(client->sock, 2); + client->close(client); + goto out; + } + qemu_co_mutex_init(&client->send_lock); + nbd_set_handlers(client); + + if (exp) { + QTAILQ_INSERT_TAIL(&exp->clients, client, next); + } +out: + g_free(data); +} + void nbd_client_new(NBDExport *exp, int csock, void (*close_fn)(NBDClient *)) { NBDClient *client; + NBDClientNewData *data = g_new(NBDClientNewData, 1); + client = g_malloc0(sizeof(NBDClient)); client->refcount = 1; client->exp = exp; client->sock = csock; client->can_read = true; - if (nbd_send_negotiate(client)) { - shutdown(client->sock, 2); - close_fn(client); - return; - } client->close = close_fn; - qemu_co_mutex_init(&client->send_lock); - nbd_set_handlers(client); - if (exp) { - QTAILQ_INSERT_TAIL(&exp->clients, client, next); - nbd_export_get(exp); - } + data->client = client; + data->co = qemu_coroutine_create(nbd_co_client_start); + qemu_coroutine_enter(data->co, data); } |