/*
- * Copyright (C) 2016 Red Hat, Inc.
+ * Copyright (C) 2016-2017 Red Hat, Inc.
*
* Network Block Device Client Side
#include "qemu/osdep.h"
#include "qapi/error.h"
+#include "trace.h"
#include "nbd-internal.h"
-static int nbd_errno_to_system_errno(int err)
-{
- int ret;
- switch (err) {
- case NBD_SUCCESS:
- ret = 0;
- break;
- case NBD_EPERM:
- ret = EPERM;
- break;
- case NBD_EIO:
- ret = EIO;
- break;
- case NBD_ENOMEM:
- ret = ENOMEM;
- break;
- case NBD_ENOSPC:
- ret = ENOSPC;
- break;
- case NBD_ESHUTDOWN:
- ret = ESHUTDOWN;
- break;
- default:
- TRACE("Squashing unexpected error %d to EINVAL", err);
- /* fallthrough */
- case NBD_EINVAL:
- ret = EINVAL;
- break;
- }
- return ret;
-}
-
/* Definitions for opaque data types */
static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports);
*/
-/* Discard length bytes from channel. Return -errno on failure, or
- * the amount of bytes consumed. */
-static ssize_t drop_sync(QIOChannel *ioc, size_t size)
-{
- ssize_t ret = 0;
- char small[1024];
- char *buffer;
-
- buffer = sizeof(small) >= size ? small : g_malloc(MIN(65536, size));
- while (size > 0) {
- ssize_t count = read_sync(ioc, buffer, MIN(65536, size));
-
- if (count <= 0) {
- goto cleanup;
- }
- assert(count <= size);
- size -= count;
- ret += count;
- }
-
- cleanup:
- if (buffer != small) {
- g_free(buffer);
- }
- return ret;
-}
-
/* Send an option request.
*
* The request is for option @opt, with @data containing @len bytes of
if (len == -1) {
req.length = len = strlen(data);
}
- TRACE("Sending option request %" PRIu32", len %" PRIu32, opt, len);
+ trace_nbd_send_option_request(opt, nbd_opt_lookup(opt), len);
stq_be_p(&req.magic, NBD_OPTS_MAGIC);
stl_be_p(&req.option, opt);
stl_be_p(&req.length, len);
- if (write_sync(ioc, &req, sizeof(req)) != sizeof(req)) {
- error_setg(errp, "Failed to send option request header");
+ if (nbd_write(ioc, &req, sizeof(req), errp) < 0) {
+ error_prepend(errp, "Failed to send option request header: ");
return -1;
}
- if (len && write_sync(ioc, (char *) data, len) != len) {
- error_setg(errp, "Failed to send option request data");
+ if (len && nbd_write(ioc, (char *) data, len, errp) < 0) {
+ error_prepend(errp, "Failed to send option request data: ");
return -1;
}
nbd_opt_reply *reply, Error **errp)
{
QEMU_BUILD_BUG_ON(sizeof(*reply) != 20);
- if (read_sync(ioc, reply, sizeof(*reply)) != sizeof(*reply)) {
- error_setg(errp, "failed to read option reply");
+ if (nbd_read(ioc, reply, sizeof(*reply), errp) < 0) {
+ error_prepend(errp, "failed to read option reply: ");
nbd_send_opt_abort(ioc);
return -1;
}
be32_to_cpus(&reply->type);
be32_to_cpus(&reply->length);
- TRACE("Received option reply %" PRIx32", type %" PRIx32", len %" PRIu32,
- reply->option, reply->type, reply->length);
+ trace_nbd_receive_option_reply(reply->option, nbd_opt_lookup(reply->option),
+ reply->type, nbd_rep_lookup(reply->type),
+ reply->length);
if (reply->magic != NBD_REP_MAGIC) {
error_setg(errp, "Unexpected option reply magic");
if (reply->length) {
if (reply->length > NBD_MAX_BUFFER_SIZE) {
- error_setg(errp, "server's error message is too long");
+ error_setg(errp, "server error 0x%" PRIx32
+ " (%s) message is too long",
+ reply->type, nbd_rep_lookup(reply->type));
goto cleanup;
}
msg = g_malloc(reply->length + 1);
- if (read_sync(ioc, msg, reply->length) != reply->length) {
- error_setg(errp, "failed to read option error message");
+ if (nbd_read(ioc, msg, reply->length, errp) < 0) {
+ error_prepend(errp, "failed to read option error 0x%" PRIx32
+ " (%s) message: ",
+ reply->type, nbd_rep_lookup(reply->type));
goto cleanup;
}
msg[reply->length] = '\0';
switch (reply->type) {
case NBD_REP_ERR_UNSUP:
- TRACE("server doesn't understand request %" PRIx32
- ", attempting fallback", reply->option);
+ trace_nbd_reply_err_unsup(reply->option, nbd_opt_lookup(reply->option));
result = 0;
goto cleanup;
case NBD_REP_ERR_POLICY:
- error_setg(errp, "Denied by server for option %" PRIx32,
- reply->option);
+ error_setg(errp, "Denied by server for option %" PRIx32 " (%s)",
+ reply->option, nbd_opt_lookup(reply->option));
break;
case NBD_REP_ERR_INVALID:
- error_setg(errp, "Invalid data length for option %" PRIx32,
- reply->option);
+ error_setg(errp, "Invalid data length for option %" PRIx32 " (%s)",
+ reply->option, nbd_opt_lookup(reply->option));
break;
case NBD_REP_ERR_PLATFORM:
- error_setg(errp, "Server lacks support for option %" PRIx32,
- reply->option);
+ error_setg(errp, "Server lacks support for option %" PRIx32 " (%s)",
+ reply->option, nbd_opt_lookup(reply->option));
break;
case NBD_REP_ERR_TLS_REQD:
- error_setg(errp, "TLS negotiation required before option %" PRIx32,
- reply->option);
+ error_setg(errp, "TLS negotiation required before option %" PRIx32
+ " (%s)", reply->option, nbd_opt_lookup(reply->option));
+ break;
+
+ case NBD_REP_ERR_UNKNOWN:
+ error_setg(errp, "Requested export not available");
break;
case NBD_REP_ERR_SHUTDOWN:
- error_setg(errp, "Server shutting down before option %" PRIx32,
- reply->option);
+ error_setg(errp, "Server shutting down before option %" PRIx32 " (%s)",
+ reply->option, nbd_opt_lookup(reply->option));
+ break;
+
+ case NBD_REP_ERR_BLOCK_SIZE_REQD:
+ error_setg(errp, "Server requires INFO_BLOCK_SIZE for option %" PRIx32
+ " (%s)", reply->option, nbd_opt_lookup(reply->option));
break;
default:
- error_setg(errp, "Unknown error code when asking for option %" PRIx32,
- reply->option);
+ error_setg(errp, "Unknown error code when asking for option %" PRIx32
+ " (%s)", reply->option, nbd_opt_lookup(reply->option));
break;
}
if (msg) {
- error_append_hint(errp, "%s\n", msg);
+ error_append_hint(errp, "server reported: %s\n", msg);
}
cleanup:
nbd_send_opt_abort(ioc);
return -1;
}
- if (read_sync(ioc, &namelen, sizeof(namelen)) != sizeof(namelen)) {
- error_setg(errp, "failed to read option name length");
+ if (nbd_read(ioc, &namelen, sizeof(namelen), errp) < 0) {
+ error_prepend(errp, "failed to read option name length: ");
nbd_send_opt_abort(ioc);
return -1;
}
return -1;
}
if (namelen != strlen(want)) {
- if (drop_sync(ioc, len) != len) {
- error_setg(errp, "failed to skip export name with wrong length");
+ if (nbd_drop(ioc, len, errp) < 0) {
+ error_prepend(errp,
+ "failed to skip export name with wrong length: ");
nbd_send_opt_abort(ioc);
return -1;
}
}
assert(namelen < sizeof(name));
- if (read_sync(ioc, name, namelen) != namelen) {
- error_setg(errp, "failed to read export name");
+ if (nbd_read(ioc, name, namelen, errp) < 0) {
+ error_prepend(errp, "failed to read export name: ");
nbd_send_opt_abort(ioc);
return -1;
}
name[namelen] = '\0';
len -= namelen;
- if (drop_sync(ioc, len) != len) {
- error_setg(errp, "failed to read export description");
+ if (nbd_drop(ioc, len, errp) < 0) {
+ error_prepend(errp, "failed to read export description: ");
nbd_send_opt_abort(ioc);
return -1;
}
}
+/* Returns -1 if NBD_OPT_GO proves the export @wantname cannot be
+ * used, 0 if NBD_OPT_GO is unsupported (fall back to NBD_OPT_LIST and
+ * NBD_OPT_EXPORT_NAME in that case), and > 0 if the export is good to
+ * go (with @info populated). */
+static int nbd_opt_go(QIOChannel *ioc, const char *wantname,
+ NBDExportInfo *info, Error **errp)
+{
+ nbd_opt_reply reply;
+ uint32_t len = strlen(wantname);
+ uint16_t type;
+ int error;
+ char *buf;
+
+ /* The protocol requires that the server send NBD_INFO_EXPORT with
+ * a non-zero flags (at least NBD_FLAG_HAS_FLAGS must be set); so
+ * flags still 0 is a witness of a broken server. */
+ info->flags = 0;
+
+ trace_nbd_opt_go_start(wantname);
+ buf = g_malloc(4 + len + 2 + 2 * info->request_sizes + 1);
+ stl_be_p(buf, len);
+ memcpy(buf + 4, wantname, len);
+ /* At most one request, everything else up to server */
+ stw_be_p(buf + 4 + len, info->request_sizes);
+ if (info->request_sizes) {
+ stw_be_p(buf + 4 + len + 2, NBD_INFO_BLOCK_SIZE);
+ }
+ error = nbd_send_option_request(ioc, NBD_OPT_GO,
+ 4 + len + 2 + 2 * info->request_sizes,
+ buf, errp);
+ g_free(buf);
+ if (error < 0) {
+ return -1;
+ }
+
+ while (1) {
+ if (nbd_receive_option_reply(ioc, NBD_OPT_GO, &reply, errp) < 0) {
+ return -1;
+ }
+ error = nbd_handle_reply_err(ioc, &reply, errp);
+ if (error <= 0) {
+ return error;
+ }
+ len = reply.length;
+
+ if (reply.type == NBD_REP_ACK) {
+ /* Server is done sending info and moved into transmission
+ phase, but make sure it sent flags */
+ if (len) {
+ error_setg(errp, "server sent invalid NBD_REP_ACK");
+ return -1;
+ }
+ if (!info->flags) {
+ error_setg(errp, "broken server omitted NBD_INFO_EXPORT");
+ return -1;
+ }
+ trace_nbd_opt_go_success();
+ return 1;
+ }
+ if (reply.type != NBD_REP_INFO) {
+ error_setg(errp, "unexpected reply type %" PRIx32
+ " (%s), expected %x",
+ reply.type, nbd_rep_lookup(reply.type), NBD_REP_INFO);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (len < sizeof(type)) {
+ error_setg(errp, "NBD_REP_INFO length %" PRIu32 " is too short",
+ len);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &type, sizeof(type), errp) < 0) {
+ error_prepend(errp, "failed to read info type: ");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ len -= sizeof(type);
+ be16_to_cpus(&type);
+ switch (type) {
+ case NBD_INFO_EXPORT:
+ if (len != sizeof(info->size) + sizeof(info->flags)) {
+ error_setg(errp, "remaining export info len %" PRIu32
+ " is unexpected size", len);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {
+ error_prepend(errp, "failed to read info size: ");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be64_to_cpus(&info->size);
+ if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) {
+ error_prepend(errp, "failed to read info flags: ");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be16_to_cpus(&info->flags);
+ trace_nbd_receive_negotiate_size_flags(info->size, info->flags);
+ break;
+
+ case NBD_INFO_BLOCK_SIZE:
+ if (len != sizeof(info->min_block) * 3) {
+ error_setg(errp, "remaining export info len %" PRIu32
+ " is unexpected size", len);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &info->min_block, sizeof(info->min_block),
+ errp) < 0) {
+ error_prepend(errp, "failed to read info minimum block size: ");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be32_to_cpus(&info->min_block);
+ if (!is_power_of_2(info->min_block)) {
+ error_setg(errp, "server minimum block size %" PRId32
+ "is not a power of two", info->min_block);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &info->opt_block, sizeof(info->opt_block),
+ errp) < 0) {
+ error_prepend(errp,
+ "failed to read info preferred block size: ");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be32_to_cpus(&info->opt_block);
+ if (!is_power_of_2(info->opt_block) ||
+ info->opt_block < info->min_block) {
+ error_setg(errp, "server preferred block size %" PRId32
+ "is not valid", info->opt_block);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &info->max_block, sizeof(info->max_block),
+ errp) < 0) {
+ error_prepend(errp, "failed to read info maximum block size: ");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be32_to_cpus(&info->max_block);
+ trace_nbd_opt_go_info_block_size(info->min_block, info->opt_block,
+ info->max_block);
+ break;
+
+ default:
+ trace_nbd_opt_go_info_unknown(type, nbd_info_lookup(type));
+ if (nbd_drop(ioc, len, errp) < 0) {
+ error_prepend(errp, "Failed to read info payload: ");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ break;
+ }
+ }
+}
+
/* Return -1 on failure, 0 if wantname is an available export. */
static int nbd_receive_query_exports(QIOChannel *ioc,
const char *wantname,
{
bool foundExport = false;
- TRACE("Querying export list for '%s'", wantname);
+ trace_nbd_receive_query_exports_start(wantname);
if (nbd_send_option_request(ioc, NBD_OPT_LIST, 0, NULL, errp) < 0) {
return -1;
}
- TRACE("Reading available export names");
while (1) {
int ret = nbd_receive_list(ioc, wantname, &foundExport, errp);
nbd_send_opt_abort(ioc);
return -1;
}
- TRACE("Found desired export name '%s'", wantname);
+ trace_nbd_receive_query_exports_success(wantname);
return 0;
}
}
}
-static QIOChannel *nbd_receive_starttls(QIOChannel *ioc,
- QCryptoTLSCreds *tlscreds,
- const char *hostname, Error **errp)
+/* nbd_request_simple_option: Send an option request, and parse the reply
+ * return 1 for successful negotiation,
+ * 0 if operation is unsupported,
+ * -1 with errp set for any other error
+ */
+static int nbd_request_simple_option(QIOChannel *ioc, int opt, Error **errp)
{
nbd_opt_reply reply;
- QIOChannelTLS *tioc;
- struct NBDTLSHandshakeData data = { 0 };
+ int error;
- TRACE("Requesting TLS from server");
- if (nbd_send_option_request(ioc, NBD_OPT_STARTTLS, 0, NULL, errp) < 0) {
- return NULL;
+ if (nbd_send_option_request(ioc, opt, 0, NULL, errp) < 0) {
+ return -1;
}
- TRACE("Getting TLS reply from server");
- if (nbd_receive_option_reply(ioc, NBD_OPT_STARTTLS, &reply, errp) < 0) {
- return NULL;
+ if (nbd_receive_option_reply(ioc, opt, &reply, errp) < 0) {
+ return -1;
+ }
+ error = nbd_handle_reply_err(ioc, &reply, errp);
+ if (error <= 0) {
+ return error;
}
if (reply.type != NBD_REP_ACK) {
- error_setg(errp, "Server rejected request to start TLS %" PRIx32,
- reply.type);
+ error_setg(errp, "Server answered option %d (%s) with unexpected "
+ "reply %" PRIx32 " (%s)", opt, nbd_opt_lookup(opt),
+ reply.type, nbd_rep_lookup(reply.type));
nbd_send_opt_abort(ioc);
- return NULL;
+ return -1;
}
if (reply.length != 0) {
- error_setg(errp, "Start TLS response was not zero %" PRIu32,
+ error_setg(errp, "Option %d ('%s') response length is %" PRIu32
+ " (it should be zero)", opt, nbd_opt_lookup(opt),
reply.length);
nbd_send_opt_abort(ioc);
+ return -1;
+ }
+
+ return 1;
+}
+
+static QIOChannel *nbd_receive_starttls(QIOChannel *ioc,
+ QCryptoTLSCreds *tlscreds,
+ const char *hostname, Error **errp)
+{
+ int ret;
+ QIOChannelTLS *tioc;
+ struct NBDTLSHandshakeData data = { 0 };
+
+ ret = nbd_request_simple_option(ioc, NBD_OPT_STARTTLS, errp);
+ if (ret <= 0) {
+ if (ret == 0) {
+ error_setg(errp, "Server don't support STARTTLS option");
+ nbd_send_opt_abort(ioc);
+ }
return NULL;
}
- TRACE("TLS request approved, setting up TLS");
+ trace_nbd_receive_starttls_new_client();
tioc = qio_channel_tls_new_client(ioc, tlscreds, hostname, errp);
if (!tioc) {
return NULL;
}
qio_channel_set_name(QIO_CHANNEL(tioc), "nbd-client-tls");
data.loop = g_main_loop_new(g_main_context_default(), FALSE);
- TRACE("Starting TLS handshake");
+ trace_nbd_receive_starttls_tls_handshake();
qio_channel_tls_handshake(tioc,
nbd_tls_handshake,
&data,
}
-int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags,
+int nbd_receive_negotiate(QIOChannel *ioc, const char *name,
QCryptoTLSCreds *tlscreds, const char *hostname,
- QIOChannel **outioc,
- off_t *size, Error **errp)
+ QIOChannel **outioc, NBDExportInfo *info,
+ Error **errp)
{
char buf[256];
- uint64_t magic, s;
+ uint64_t magic;
int rc;
bool zeroes = true;
+ bool structured_reply = info->structured_reply;
- TRACE("Receiving negotiation tlscreds=%p hostname=%s.",
- tlscreds, hostname ? hostname : "<null>");
+ trace_nbd_receive_negotiate(tlscreds, hostname ? hostname : "<null>");
+ info->structured_reply = false;
rc = -EINVAL;
if (outioc) {
goto fail;
}
- if (read_sync(ioc, buf, 8) != 8) {
- error_setg(errp, "Failed to read data");
+ if (nbd_read(ioc, buf, 8, errp) < 0) {
+ error_prepend(errp, "Failed to read data: ");
goto fail;
}
goto fail;
}
- TRACE("Magic is %c%c%c%c%c%c%c%c",
- qemu_isprint(buf[0]) ? buf[0] : '.',
- qemu_isprint(buf[1]) ? buf[1] : '.',
- qemu_isprint(buf[2]) ? buf[2] : '.',
- qemu_isprint(buf[3]) ? buf[3] : '.',
- qemu_isprint(buf[4]) ? buf[4] : '.',
- qemu_isprint(buf[5]) ? buf[5] : '.',
- qemu_isprint(buf[6]) ? buf[6] : '.',
- qemu_isprint(buf[7]) ? buf[7] : '.');
+ magic = ldq_be_p(buf);
+ trace_nbd_receive_negotiate_magic(magic);
if (memcmp(buf, "NBDMAGIC", 8) != 0) {
error_setg(errp, "Invalid magic received");
goto fail;
}
- if (read_sync(ioc, &magic, sizeof(magic)) != sizeof(magic)) {
- error_setg(errp, "Failed to read magic");
+ if (nbd_read(ioc, &magic, sizeof(magic), errp) < 0) {
+ error_prepend(errp, "Failed to read magic: ");
goto fail;
}
magic = be64_to_cpu(magic);
- TRACE("Magic is 0x%" PRIx64, magic);
+ trace_nbd_receive_negotiate_magic(magic);
if (magic == NBD_OPTS_MAGIC) {
uint32_t clientflags = 0;
uint16_t globalflags;
bool fixedNewStyle = false;
- if (read_sync(ioc, &globalflags, sizeof(globalflags)) !=
- sizeof(globalflags)) {
- error_setg(errp, "Failed to read server flags");
+ if (nbd_read(ioc, &globalflags, sizeof(globalflags), errp) < 0) {
+ error_prepend(errp, "Failed to read server flags: ");
goto fail;
}
globalflags = be16_to_cpu(globalflags);
- TRACE("Global flags are %" PRIx32, globalflags);
+ trace_nbd_receive_negotiate_server_flags(globalflags);
if (globalflags & NBD_FLAG_FIXED_NEWSTYLE) {
fixedNewStyle = true;
- TRACE("Server supports fixed new style");
clientflags |= NBD_FLAG_C_FIXED_NEWSTYLE;
}
if (globalflags & NBD_FLAG_NO_ZEROES) {
zeroes = false;
- TRACE("Server supports no zeroes");
clientflags |= NBD_FLAG_C_NO_ZEROES;
}
/* client requested flags */
clientflags = cpu_to_be32(clientflags);
- if (write_sync(ioc, &clientflags, sizeof(clientflags)) !=
- sizeof(clientflags)) {
- error_setg(errp, "Failed to send clientflags field");
+ if (nbd_write(ioc, &clientflags, sizeof(clientflags), errp) < 0) {
+ error_prepend(errp, "Failed to send clientflags field: ");
goto fail;
}
if (tlscreds) {
}
}
if (!name) {
- TRACE("Using default NBD export name \"\"");
+ trace_nbd_receive_negotiate_default_name();
name = "";
}
if (fixedNewStyle) {
+ int result;
+
+ if (structured_reply) {
+ result = nbd_request_simple_option(ioc,
+ NBD_OPT_STRUCTURED_REPLY,
+ errp);
+ if (result < 0) {
+ goto fail;
+ }
+ info->structured_reply = result == 1;
+ }
+
+ /* Try NBD_OPT_GO first - if it works, we are done (it
+ * also gives us a good message if the server requires
+ * TLS). If it is not available, fall back to
+ * NBD_OPT_LIST for nicer error messages about a missing
+ * export, then use NBD_OPT_EXPORT_NAME. */
+ result = nbd_opt_go(ioc, name, info, errp);
+ if (result < 0) {
+ goto fail;
+ }
+ if (result > 0) {
+ return 0;
+ }
/* Check our desired export is present in the
* server export list. Since NBD_OPT_EXPORT_NAME
* cannot return an error message, running this
- * query gives us good error reporting if the
- * server required TLS
+ * query gives us better error reporting if the
+ * export name is not available.
*/
if (nbd_receive_query_exports(ioc, name, errp) < 0) {
goto fail;
}
/* Read the response */
- if (read_sync(ioc, &s, sizeof(s)) != sizeof(s)) {
- error_setg(errp, "Failed to read export length");
+ if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {
+ error_prepend(errp, "Failed to read export length: ");
goto fail;
}
- *size = be64_to_cpu(s);
+ be64_to_cpus(&info->size);
- if (read_sync(ioc, flags, sizeof(*flags)) != sizeof(*flags)) {
- error_setg(errp, "Failed to read export flags");
+ if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) {
+ error_prepend(errp, "Failed to read export flags: ");
goto fail;
}
- be16_to_cpus(flags);
+ be16_to_cpus(&info->flags);
} else if (magic == NBD_CLIENT_MAGIC) {
uint32_t oldflags;
goto fail;
}
- if (read_sync(ioc, &s, sizeof(s)) != sizeof(s)) {
- error_setg(errp, "Failed to read export length");
+ if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {
+ error_prepend(errp, "Failed to read export length: ");
goto fail;
}
- *size = be64_to_cpu(s);
- TRACE("Size is %" PRIu64, *size);
+ be64_to_cpus(&info->size);
- if (read_sync(ioc, &oldflags, sizeof(oldflags)) != sizeof(oldflags)) {
- error_setg(errp, "Failed to read export flags");
+ if (nbd_read(ioc, &oldflags, sizeof(oldflags), errp) < 0) {
+ error_prepend(errp, "Failed to read export flags: ");
goto fail;
}
be32_to_cpus(&oldflags);
error_setg(errp, "Unexpected export flags %0x" PRIx32, oldflags);
goto fail;
}
- *flags = oldflags;
+ info->flags = oldflags;
} else {
error_setg(errp, "Bad magic received");
goto fail;
}
- TRACE("Size is %" PRIu64 ", export flags %" PRIx16, *size, *flags);
- if (zeroes && drop_sync(ioc, 124) != 124) {
- error_setg(errp, "Failed to read reserved block");
+ trace_nbd_receive_negotiate_size_flags(info->size, info->flags);
+ if (zeroes && nbd_drop(ioc, 124, errp) < 0) {
+ error_prepend(errp, "Failed to read reserved block: ");
goto fail;
}
rc = 0;
}
#ifdef __linux__
-int nbd_init(int fd, QIOChannelSocket *sioc, uint16_t flags, off_t size)
+int nbd_init(int fd, QIOChannelSocket *sioc, NBDExportInfo *info,
+ Error **errp)
{
- unsigned long sectors = size / BDRV_SECTOR_SIZE;
- if (size / BDRV_SECTOR_SIZE != sectors) {
- LOG("Export size %lld too large for 32-bit kernel", (long long) size);
+ unsigned long sector_size = MAX(BDRV_SECTOR_SIZE, info->min_block);
+ unsigned long sectors = info->size / sector_size;
+
+ /* FIXME: Once the kernel module is patched to honor block sizes,
+ * and to advertise that fact to user space, we should update the
+ * hand-off to the kernel to use any block sizes we learned. */
+ assert(!info->request_sizes);
+ if (info->size / sector_size != sectors) {
+ error_setg(errp, "Export size %" PRIu64 " too large for 32-bit kernel",
+ info->size);
return -E2BIG;
}
- TRACE("Setting NBD socket");
+ trace_nbd_init_set_socket();
if (ioctl(fd, NBD_SET_SOCK, (unsigned long) sioc->fd) < 0) {
int serrno = errno;
- LOG("Failed to set NBD socket");
+ error_setg(errp, "Failed to set NBD socket");
return -serrno;
}
- TRACE("Setting block size to %lu", (unsigned long)BDRV_SECTOR_SIZE);
+ trace_nbd_init_set_block_size(sector_size);
- if (ioctl(fd, NBD_SET_BLKSIZE, (unsigned long)BDRV_SECTOR_SIZE) < 0) {
+ if (ioctl(fd, NBD_SET_BLKSIZE, sector_size) < 0) {
int serrno = errno;
- LOG("Failed setting NBD block size");
+ error_setg(errp, "Failed setting NBD block size");
return -serrno;
}
- TRACE("Setting size to %lu block(s)", sectors);
- if (size % BDRV_SECTOR_SIZE) {
- TRACE("Ignoring trailing %d bytes of export",
- (int) (size % BDRV_SECTOR_SIZE));
+ trace_nbd_init_set_size(sectors);
+ if (info->size % sector_size) {
+ trace_nbd_init_trailing_bytes(info->size % sector_size);
}
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, sectors) < 0) {
int serrno = errno;
- LOG("Failed setting size (in blocks)");
+ error_setg(errp, "Failed setting size (in blocks)");
return -serrno;
}
- if (ioctl(fd, NBD_SET_FLAGS, (unsigned long) flags) < 0) {
+ if (ioctl(fd, NBD_SET_FLAGS, (unsigned long) info->flags) < 0) {
if (errno == ENOTTY) {
- int read_only = (flags & NBD_FLAG_READ_ONLY) != 0;
- TRACE("Setting readonly attribute");
+ int read_only = (info->flags & NBD_FLAG_READ_ONLY) != 0;
+ trace_nbd_init_set_readonly();
if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
int serrno = errno;
- LOG("Failed setting read-only attribute");
+ error_setg(errp, "Failed setting read-only attribute");
return -serrno;
}
} else {
int serrno = errno;
- LOG("Failed setting flags");
+ error_setg(errp, "Failed setting flags");
return -serrno;
}
}
- TRACE("Negotiation ended");
+ trace_nbd_init_finish();
return 0;
}
int ret;
int serrno;
- TRACE("Doing NBD loop");
+ trace_nbd_client_loop();
ret = ioctl(fd, NBD_DO_IT);
if (ret < 0 && errno == EPIPE) {
}
serrno = errno;
- TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
+ trace_nbd_client_loop_ret(ret, strerror(serrno));
- TRACE("Clearing NBD queue");
+ trace_nbd_client_clear_queue();
ioctl(fd, NBD_CLEAR_QUE);
- TRACE("Clearing NBD socket");
+ trace_nbd_client_clear_socket();
ioctl(fd, NBD_CLEAR_SOCK);
errno = serrno;
}
#else
-int nbd_init(int fd, QIOChannelSocket *ioc, uint16_t flags, off_t size)
+int nbd_init(int fd, QIOChannelSocket *ioc, NBDExportInfo *info,
+ Error **errp)
{
+ error_setg(errp, "nbd_init is only supported on Linux");
return -ENOTSUP;
}
}
#endif
-ssize_t nbd_send_request(QIOChannel *ioc, NBDRequest *request)
+int nbd_send_request(QIOChannel *ioc, NBDRequest *request)
{
uint8_t buf[NBD_REQUEST_SIZE];
- ssize_t ret;
- TRACE("Sending request to server: "
- "{ .from = %" PRIu64", .len = %" PRIu32 ", .handle = %" PRIu64
- ", .flags = %" PRIx16 ", .type = %" PRIu16 " }",
- request->from, request->len, request->handle,
- request->flags, request->type);
+ trace_nbd_send_request(request->from, request->len, request->handle,
+ request->flags, request->type,
+ nbd_cmd_lookup(request->type));
stl_be_p(buf, NBD_REQUEST_MAGIC);
stw_be_p(buf + 4, request->flags);
stq_be_p(buf + 16, request->from);
stl_be_p(buf + 24, request->len);
- ret = write_sync(ioc, buf, sizeof(buf));
+ return nbd_write(ioc, buf, sizeof(buf), NULL);
+}
+
+/* nbd_receive_simple_reply
+ * Read simple reply except magic field (which should be already read).
+ * Payload is not read (payload is possible for CMD_READ, but here we even
+ * don't know whether it take place or not).
+ */
+static int nbd_receive_simple_reply(QIOChannel *ioc, NBDSimpleReply *reply,
+ Error **errp)
+{
+ int ret;
+
+ assert(reply->magic == NBD_SIMPLE_REPLY_MAGIC);
+
+ ret = nbd_read(ioc, (uint8_t *)reply + sizeof(reply->magic),
+ sizeof(*reply) - sizeof(reply->magic), errp);
if (ret < 0) {
return ret;
}
- if (ret != sizeof(buf)) {
- LOG("writing to socket failed");
- return -EINVAL;
- }
+ be32_to_cpus(&reply->error);
+ be64_to_cpus(&reply->handle);
+
return 0;
}
-ssize_t nbd_receive_reply(QIOChannel *ioc, NBDReply *reply)
+/* nbd_receive_structured_reply_chunk
+ * Read structured reply chunk except magic field (which should be already
+ * read).
+ * Payload is not read.
+ */
+static int nbd_receive_structured_reply_chunk(QIOChannel *ioc,
+ NBDStructuredReplyChunk *chunk,
+ Error **errp)
{
- uint8_t buf[NBD_REPLY_SIZE];
- uint32_t magic;
- ssize_t ret;
+ int ret;
- ret = read_sync(ioc, buf, sizeof(buf));
- if (ret <= 0) {
- return ret;
- }
+ assert(chunk->magic == NBD_STRUCTURED_REPLY_MAGIC);
- if (ret != sizeof(buf)) {
- LOG("read failed");
- return -EINVAL;
+ ret = nbd_read(ioc, (uint8_t *)chunk + sizeof(chunk->magic),
+ sizeof(*chunk) - sizeof(chunk->magic), errp);
+ if (ret < 0) {
+ return ret;
}
- /* Reply
- [ 0 .. 3] magic (NBD_REPLY_MAGIC)
- [ 4 .. 7] error (0 == no error)
- [ 7 .. 15] handle
- */
+ be16_to_cpus(&chunk->flags);
+ be16_to_cpus(&chunk->type);
+ be64_to_cpus(&chunk->handle);
+ be32_to_cpus(&chunk->length);
- magic = ldl_be_p(buf);
- reply->error = ldl_be_p(buf + 4);
- reply->handle = ldq_be_p(buf + 8);
+ return 0;
+}
- reply->error = nbd_errno_to_system_errno(reply->error);
+/* nbd_receive_reply
+ * Returns 1 on success
+ * 0 on eof, when no data was read (errp is not set)
+ * negative errno on failure (errp is set)
+ */
+int nbd_receive_reply(QIOChannel *ioc, NBDReply *reply, Error **errp)
+{
+ int ret;
+ const char *type;
- if (reply->error == ESHUTDOWN) {
- /* This works even on mingw which lacks a native ESHUTDOWN */
- LOG("server shutting down");
- return -EINVAL;
+ ret = nbd_read_eof(ioc, &reply->magic, sizeof(reply->magic), errp);
+ if (ret <= 0) {
+ return ret;
}
- TRACE("Got reply: { magic = 0x%" PRIx32 ", .error = % " PRId32
- ", handle = %" PRIu64" }",
- magic, reply->error, reply->handle);
- if (magic != NBD_REPLY_MAGIC) {
- LOG("invalid magic (got 0x%" PRIx32 ")", magic);
+ be32_to_cpus(&reply->magic);
+
+ switch (reply->magic) {
+ case NBD_SIMPLE_REPLY_MAGIC:
+ ret = nbd_receive_simple_reply(ioc, &reply->simple, errp);
+ if (ret < 0) {
+ break;
+ }
+ trace_nbd_receive_simple_reply(reply->simple.error,
+ nbd_err_lookup(reply->simple.error),
+ reply->handle);
+ break;
+ case NBD_STRUCTURED_REPLY_MAGIC:
+ ret = nbd_receive_structured_reply_chunk(ioc, &reply->structured, errp);
+ if (ret < 0) {
+ break;
+ }
+ type = nbd_reply_type_lookup(reply->structured.type);
+ trace_nbd_receive_structured_reply_chunk(reply->structured.flags,
+ reply->structured.type, type,
+ reply->structured.handle,
+ reply->structured.length);
+ break;
+ default:
+ error_setg(errp, "invalid magic (got 0x%" PRIx32 ")", reply->magic);
return -EINVAL;
}
- return sizeof(buf);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return 1;
}
projects / qemu.git / blobdiff