From 0ae2d54645eb2888af6dc7f701bc02ca18e4e656 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Fri, 25 Jan 2019 17:48:37 -0600 Subject: [PATCH 1/8] qemu-nbd: Deprecate qemu-nbd --partition The existing qemu-nbd --partition code claims to handle logical partitions up to 8, since its introduction in 2008 (commit 7a5ca86). However, the implementation is bogus (actual MBR logical partitions form a sort of linked list, with one partition per extended table entry, rather than four logical partitions in a single extended table), making the code unlikely to work for anything beyond -P5 on actual guest images. What's more, the code does not support GPT partitions, which are becoming more popular, and maintaining device subsetting in both NBD and the raw device is unnecessary duplication of effort (even if it is not too difficult). Note that obtaining the offsets of a partition (MBR or GPT) can be learned by using 'qemu-nbd -c /dev/nbd0 file.qcow2 && sfdisk --dump /dev/nbd0', but by the time you've done that, you might as well just mount /dev/nbd0p1 that the kernel creates for you instead of bothering with qemu exporting a subset. Or, keeping to just user-space code, use nbdkit's partition filter, which has already known both GPT and primary MBR partitions for a while, and was just recently enhanced to support arbitrary logical MBR parititions. Start the clock on the deprecation cycle, with examples of how to accomplish device subsetting without using -P. Signed-off-by: Eric Blake Message-Id: <20190125234837.2272-1-eblake@redhat.com> Reviewed-by: Richard W.M. Jones Reviewed-by: Stefano Garzarella --- qemu-deprecated.texi | 33 +++++++++++++++++++++++++++++++++ qemu-nbd.c | 2 ++ qemu-nbd.texi | 6 ++++-- 3 files changed, 39 insertions(+), 2 deletions(-) diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi index 9cc20b365c..8a6174df0c 100644 --- a/qemu-deprecated.texi +++ b/qemu-deprecated.texi @@ -160,3 +160,36 @@ Example of legacy encoding: The above, converted to the current supported format: @code{json:@{"file.driver":"rbd", "file.pool":"rbd", "file.image":"name"@}} + +@section Related binaries + +@subsection qemu-nbd --partition (since 4.0.0) + +The ``qemu-nbd --partition $digit'' code (also spelled @option{-P}) +can only handle MBR partitions, and has never correctly handled +logical partitions beyond partition 5. If you know the offset and +length of the partition (perhaps by using @code{sfdisk} within the +guest), you can achieve the effect of exporting just that subset of +the disk by use of the @option{--image-opts} option with a raw +blockdev using the @code{offset} and @code{size} parameters layered on +top of any other existing blockdev. For example, if partition 1 is +100MiB long starting at 1MiB, the old command: + +@code{qemu-nbd -t -P 1 -f qcow2 file.qcow2} + +can be rewritten as: + +@code{qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.backing.driver=file,file.backing.filename=file.qcow2} + +Alternatively, the @code{nbdkit} project provides a more powerful +partition filter on top of its nbd plugin, which can be used to select +an arbitrary MBR or GPT partition on top of any other full-image NBD +export. Using this to rewrite the above example results in: + +@code{qemu-nbd -t -k /tmp/sock -f qcow2 file.qcow2 &} +@code{nbdkit -f --filter=partition nbd socket=/tmp/sock partition=1} + +Note that if you are exposing the export via /dev/nbd0, it is easier +to just export the entire image and then mount only /dev/nbd0p1 than +it is to reinvoke @command{qemu-nbd -c /dev/nbd0} limited to just a +subset of the image. diff --git a/qemu-nbd.c b/qemu-nbd.c index 1f7b2a03f5..00c07fd27e 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -787,6 +787,8 @@ int main(int argc, char **argv) flags &= ~BDRV_O_RDWR; break; case 'P': + warn_report("The '-P' option is deprecated; use --image-opts with " + "a raw device wrapper for subset exports instead"); if (qemu_strtoi(optarg, NULL, 0, &partition) < 0 || partition < 1 || partition > 8) { error_report("Invalid partition '%s'", optarg); diff --git a/qemu-nbd.texi b/qemu-nbd.texi index 386bece468..d0c5182814 100644 --- a/qemu-nbd.texi +++ b/qemu-nbd.texi @@ -56,8 +56,10 @@ auto-detecting. @item -r, --read-only Export the disk as read-only. @item -P, --partition=@var{num} -Only expose MBR partition @var{num}. Understands physical partitions -1-4 and logical partitions 5-8. +Deprecated: Only expose MBR partition @var{num}. Understands physical +partitions 1-4 and logical partition 5. New code should instead use +@option{--image-opts} with the raw driver wrapping a subset of the +original image. @item -B, --bitmap=@var{name} If @var{filename} has a qcow2 persistent bitmap @var{name}, expose that bitmap via the ``qemu:dirty-bitmap:@var{name}'' context From e6798f06a67a25def45a6636259de38cc38f1414 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Mon, 28 Jan 2019 19:58:30 +0300 Subject: [PATCH 2/8] nbd: generalize usage of nbd_read We generally do very similar things around nbd_read: error_prepend specifying what we have tried to read, and be_to_cpu conversion of integers. So, it seems reasonable to move common things to helper functions, which: 1. simplify code a bit 2. generalize nbd_read error descriptions, all starting with "Failed to read" 3. make it more difficult to forget to convert things from BE Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake Message-Id: <20190128165830.165170-1-vsementsov@virtuozzo.com> [eblake: rename macro to DEF_NBD_READ_N and formatting tweaks; checkpatch has false positive complaint] Signed-off-by: Eric Blake --- block/nbd-client.c | 5 ++- include/block/nbd.h | 32 +++++++++++++++-- nbd/client.c | 88 +++++++++++++++------------------------------ nbd/common.c | 2 +- nbd/server.c | 27 +++++--------- 5 files changed, 71 insertions(+), 83 deletions(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index 50a8dadd85..57f679ad4d 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -338,10 +338,9 @@ static int nbd_co_receive_offset_data_payload(NBDClientSession *s, return -EINVAL; } - if (nbd_read(s->ioc, &offset, sizeof(offset), errp) < 0) { + if (nbd_read64(s->ioc, &offset, "OFFSET_DATA offset", errp) < 0) { return -EIO; } - be64_to_cpus(&offset); data_size = chunk->length - sizeof(offset); assert(data_size); @@ -388,7 +387,7 @@ static coroutine_fn int nbd_co_receive_structured_payload( } *payload = g_new(char, len); - ret = nbd_read(s->ioc, *payload, len, errp); + ret = nbd_read(s->ioc, *payload, len, "structured payload", errp); if (ret < 0) { g_free(*payload); *payload = NULL; diff --git a/include/block/nbd.h b/include/block/nbd.h index 4faf394e34..96cfb1d7d5 100644 --- a/include/block/nbd.h +++ b/include/block/nbd.h @@ -23,6 +23,7 @@ #include "qapi/qapi-types-block.h" #include "io/channel-socket.h" #include "crypto/tlscreds.h" +#include "qapi/error.h" /* Handshake phase structs - this struct is passed on the wire */ @@ -336,11 +337,38 @@ void nbd_server_start(SocketAddress *addr, const char *tls_creds, * Reads @size bytes from @ioc. Returns 0 on success. */ static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size, - Error **errp) + const char *desc, Error **errp) { - return qio_channel_read_all(ioc, buffer, size, errp) < 0 ? -EIO : 0; + int ret = qio_channel_read_all(ioc, buffer, size, errp) < 0 ? -EIO : 0; + + if (ret < 0) { + if (desc) { + error_prepend(errp, "Failed to read %s: ", desc); + } + return -1; + } + + return 0; } +#define DEF_NBD_READ_N(bits) \ +static inline int nbd_read##bits(QIOChannel *ioc, \ + uint##bits##_t *val, \ + const char *desc, Error **errp) \ +{ \ + if (nbd_read(ioc, val, sizeof(*val), desc, errp) < 0) { \ + return -1; \ + } \ + *val = be##bits##_to_cpu(*val); \ + return 0; \ +} + +DEF_NBD_READ_N(16) /* Defines nbd_read16(). */ +DEF_NBD_READ_N(32) /* Defines nbd_read32(). */ +DEF_NBD_READ_N(64) /* Defines nbd_read64(). */ + +#undef DEF_NBD_READ_N + static inline bool nbd_reply_is_simple(NBDReply *reply) { return reply->magic == NBD_SIMPLE_REPLY_MAGIC; diff --git a/nbd/client.c b/nbd/client.c index 8a083c2f42..10a52ad7d0 100644 --- a/nbd/client.c +++ b/nbd/client.c @@ -113,8 +113,7 @@ static int nbd_receive_option_reply(QIOChannel *ioc, uint32_t opt, NBDOptionReply *reply, Error **errp) { QEMU_BUILD_BUG_ON(sizeof(*reply) != 20); - if (nbd_read(ioc, reply, sizeof(*reply), errp) < 0) { - error_prepend(errp, "failed to read option reply: "); + if (nbd_read(ioc, reply, sizeof(*reply), "option reply", errp) < 0) { nbd_send_opt_abort(ioc); return -1; } @@ -166,8 +165,8 @@ static int nbd_handle_reply_err(QIOChannel *ioc, NBDOptionReply *reply, goto cleanup; } msg = g_malloc(reply->length + 1); - if (nbd_read(ioc, msg, reply->length, errp) < 0) { - error_prepend(errp, "failed to read option error %" PRIu32 + if (nbd_read(ioc, msg, reply->length, NULL, errp) < 0) { + error_prepend(errp, "Failed to read option error %" PRIu32 " (%s) message: ", reply->type, nbd_rep_lookup(reply->type)); goto cleanup; @@ -284,12 +283,10 @@ static int nbd_receive_list(QIOChannel *ioc, char **name, char **description, nbd_send_opt_abort(ioc); return -1; } - if (nbd_read(ioc, &namelen, sizeof(namelen), errp) < 0) { - error_prepend(errp, "failed to read option name length: "); + if (nbd_read32(ioc, &namelen, "option name length", errp) < 0) { nbd_send_opt_abort(ioc); return -1; } - namelen = be32_to_cpu(namelen); len -= sizeof(namelen); if (len < namelen) { error_setg(errp, "incorrect option name length"); @@ -298,8 +295,7 @@ static int nbd_receive_list(QIOChannel *ioc, char **name, char **description, } local_name = g_malloc(namelen + 1); - if (nbd_read(ioc, local_name, namelen, errp) < 0) { - error_prepend(errp, "failed to read export name: "); + if (nbd_read(ioc, local_name, namelen, "export name", errp) < 0) { nbd_send_opt_abort(ioc); goto out; } @@ -307,8 +303,7 @@ static int nbd_receive_list(QIOChannel *ioc, char **name, char **description, len -= namelen; if (len) { local_desc = g_malloc(len + 1); - if (nbd_read(ioc, local_desc, len, errp) < 0) { - error_prepend(errp, "failed to read export description: "); + if (nbd_read(ioc, local_desc, len, "export description", errp) < 0) { nbd_send_opt_abort(ioc); goto out; } @@ -410,13 +405,11 @@ static int nbd_opt_info_or_go(QIOChannel *ioc, uint32_t opt, nbd_send_opt_abort(ioc); return -1; } - if (nbd_read(ioc, &type, sizeof(type), errp) < 0) { - error_prepend(errp, "failed to read info type: "); + if (nbd_read16(ioc, &type, "info type", errp) < 0) { nbd_send_opt_abort(ioc); return -1; } len -= sizeof(type); - type = be16_to_cpu(type); switch (type) { case NBD_INFO_EXPORT: if (len != sizeof(info->size) + sizeof(info->flags)) { @@ -425,18 +418,14 @@ static int nbd_opt_info_or_go(QIOChannel *ioc, uint32_t opt, 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: "); + if (nbd_read64(ioc, &info->size, "info size", errp) < 0) { nbd_send_opt_abort(ioc); return -1; } - info->size = be64_to_cpu(info->size); - if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) { - error_prepend(errp, "failed to read info flags: "); + if (nbd_read16(ioc, &info->flags, "info flags", errp) < 0) { nbd_send_opt_abort(ioc); return -1; } - info->flags = be16_to_cpu(info->flags); trace_nbd_receive_negotiate_size_flags(info->size, info->flags); break; @@ -447,27 +436,23 @@ static int nbd_opt_info_or_go(QIOChannel *ioc, uint32_t opt, 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: "); + if (nbd_read32(ioc, &info->min_block, "info minimum block size", + errp) < 0) { nbd_send_opt_abort(ioc); return -1; } - info->min_block = be32_to_cpu(info->min_block); if (!is_power_of_2(info->min_block)) { error_setg(errp, "server minimum block size %" PRIu32 " 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: "); + if (nbd_read32(ioc, &info->opt_block, "info preferred block size", + errp) < 0) + { nbd_send_opt_abort(ioc); return -1; } - info->opt_block = be32_to_cpu(info->opt_block); if (!is_power_of_2(info->opt_block) || info->opt_block < info->min_block) { error_setg(errp, "server preferred block size %" PRIu32 @@ -475,13 +460,12 @@ static int nbd_opt_info_or_go(QIOChannel *ioc, uint32_t opt, 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: "); + if (nbd_read32(ioc, &info->max_block, "info maximum block size", + errp) < 0) + { nbd_send_opt_abort(ioc); return -1; } - info->max_block = be32_to_cpu(info->max_block); if (info->max_block < info->min_block) { error_setg(errp, "server maximum block size %" PRIu32 " is not valid", info->max_block); @@ -731,14 +715,13 @@ static int nbd_receive_one_meta_context(QIOChannel *ioc, return -1; } - if (nbd_read(ioc, &local_id, sizeof(local_id), errp) < 0) { + if (nbd_read32(ioc, &local_id, "context id", errp) < 0) { return -1; } - local_id = be32_to_cpu(local_id); reply.length -= sizeof(local_id); local_name = g_malloc(reply.length + 1); - if (nbd_read(ioc, local_name, reply.length, errp) < 0) { + if (nbd_read(ioc, local_name, reply.length, "context name", errp) < 0) { g_free(local_name); return -1; } @@ -896,11 +879,9 @@ static int nbd_start_negotiate(QIOChannel *ioc, QCryptoTLSCreds *tlscreds, return -EINVAL; } - if (nbd_read(ioc, &magic, sizeof(magic), errp) < 0) { - error_prepend(errp, "Failed to read initial magic: "); + if (nbd_read64(ioc, &magic, "initial magic", errp) < 0) { return -EINVAL; } - magic = be64_to_cpu(magic); trace_nbd_receive_negotiate_magic(magic); if (magic != NBD_INIT_MAGIC) { @@ -908,11 +889,9 @@ static int nbd_start_negotiate(QIOChannel *ioc, QCryptoTLSCreds *tlscreds, return -EINVAL; } - if (nbd_read(ioc, &magic, sizeof(magic), errp) < 0) { - error_prepend(errp, "Failed to read server magic: "); + if (nbd_read64(ioc, &magic, "server magic", errp) < 0) { return -EINVAL; } - magic = be64_to_cpu(magic); trace_nbd_receive_negotiate_magic(magic); if (magic == NBD_OPTS_MAGIC) { @@ -920,11 +899,9 @@ static int nbd_start_negotiate(QIOChannel *ioc, QCryptoTLSCreds *tlscreds, uint16_t globalflags; bool fixedNewStyle = false; - if (nbd_read(ioc, &globalflags, sizeof(globalflags), errp) < 0) { - error_prepend(errp, "Failed to read server flags: "); + if (nbd_read16(ioc, &globalflags, "server flags", errp) < 0) { return -EINVAL; } - globalflags = be16_to_cpu(globalflags); trace_nbd_receive_negotiate_server_flags(globalflags); if (globalflags & NBD_FLAG_FIXED_NEWSTYLE) { fixedNewStyle = true; @@ -992,17 +969,13 @@ static int nbd_negotiate_finish_oldstyle(QIOChannel *ioc, NBDExportInfo *info, { uint32_t oldflags; - if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) { - error_prepend(errp, "Failed to read export length: "); + if (nbd_read64(ioc, &info->size, "export length", errp) < 0) { return -EINVAL; } - info->size = be64_to_cpu(info->size); - if (nbd_read(ioc, &oldflags, sizeof(oldflags), errp) < 0) { - error_prepend(errp, "Failed to read export flags: "); + if (nbd_read32(ioc, &oldflags, "export flags", errp) < 0) { return -EINVAL; } - oldflags = be32_to_cpu(oldflags); if (oldflags & ~0xffff) { error_setg(errp, "Unexpected export flags %0x" PRIx32, oldflags); return -EINVAL; @@ -1079,17 +1052,13 @@ int nbd_receive_negotiate(QIOChannel *ioc, QCryptoTLSCreds *tlscreds, } /* Read the response */ - if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) { - error_prepend(errp, "Failed to read export length: "); + if (nbd_read64(ioc, &info->size, "export length", errp) < 0) { return -EINVAL; } - info->size = be64_to_cpu(info->size); - if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) { - error_prepend(errp, "Failed to read export flags: "); + if (nbd_read16(ioc, &info->flags, "export flags", errp) < 0) { return -EINVAL; } - info->flags = be16_to_cpu(info->flags); break; case 0: /* oldstyle, parse length and flags */ if (*info->name) { @@ -1379,7 +1348,7 @@ static int nbd_receive_simple_reply(QIOChannel *ioc, NBDSimpleReply *reply, assert(reply->magic == NBD_SIMPLE_REPLY_MAGIC); ret = nbd_read(ioc, (uint8_t *)reply + sizeof(reply->magic), - sizeof(*reply) - sizeof(reply->magic), errp); + sizeof(*reply) - sizeof(reply->magic), "reply", errp); if (ret < 0) { return ret; } @@ -1404,7 +1373,8 @@ static int nbd_receive_structured_reply_chunk(QIOChannel *ioc, assert(chunk->magic == NBD_STRUCTURED_REPLY_MAGIC); ret = nbd_read(ioc, (uint8_t *)chunk + sizeof(chunk->magic), - sizeof(*chunk) - sizeof(chunk->magic), errp); + sizeof(*chunk) - sizeof(chunk->magic), "structured chunk", + errp); if (ret < 0) { return ret; } diff --git a/nbd/common.c b/nbd/common.c index 41f5ed8d9f..cc8b278e54 100644 --- a/nbd/common.c +++ b/nbd/common.c @@ -31,7 +31,7 @@ int nbd_drop(QIOChannel *ioc, size_t size, Error **errp) buffer = sizeof(small) >= size ? small : g_malloc(MIN(65536, size)); while (size > 0) { ssize_t count = MIN(65536, size); - ret = nbd_read(ioc, buffer, MIN(65536, size), errp); + ret = nbd_read(ioc, buffer, MIN(65536, size), NULL, errp); if (ret < 0) { goto cleanup; diff --git a/nbd/server.c b/nbd/server.c index cb0d5634fa..838c150d8c 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -438,8 +438,7 @@ static int nbd_negotiate_handle_export_name(NBDClient *client, error_setg(errp, "Bad length received"); return -EINVAL; } - if (nbd_read(client->ioc, name, client->optlen, errp) < 0) { - error_prepend(errp, "read failed: "); + if (nbd_read(client->ioc, name, client->optlen, "export name", errp) < 0) { return -EIO; } name[client->optlen] = '\0'; @@ -1046,11 +1045,9 @@ static int nbd_negotiate_options(NBDClient *client, uint16_t myflags, ... Rest of request */ - if (nbd_read(client->ioc, &flags, sizeof(flags), errp) < 0) { - error_prepend(errp, "read failed: "); + if (nbd_read32(client->ioc, &flags, "flags", errp) < 0) { return -EIO; } - flags = be32_to_cpu(flags); trace_nbd_negotiate_options_flags(flags); if (flags & NBD_FLAG_C_FIXED_NEWSTYLE) { fixedNewstyle = true; @@ -1070,30 +1067,23 @@ static int nbd_negotiate_options(NBDClient *client, uint16_t myflags, uint32_t option, length; uint64_t magic; - if (nbd_read(client->ioc, &magic, sizeof(magic), errp) < 0) { - error_prepend(errp, "read failed: "); + if (nbd_read64(client->ioc, &magic, "opts magic", errp) < 0) { return -EINVAL; } - magic = be64_to_cpu(magic); trace_nbd_negotiate_options_check_magic(magic); if (magic != NBD_OPTS_MAGIC) { error_setg(errp, "Bad magic received"); return -EINVAL; } - if (nbd_read(client->ioc, &option, - sizeof(option), errp) < 0) { - error_prepend(errp, "read failed: "); + if (nbd_read32(client->ioc, &option, "option", errp) < 0) { return -EINVAL; } - option = be32_to_cpu(option); client->opt = option; - if (nbd_read(client->ioc, &length, sizeof(length), errp) < 0) { - error_prepend(errp, "read failed: "); + if (nbd_read32(client->ioc, &length, "option length", errp) < 0) { return -EINVAL; } - length = be32_to_cpu(length); assert(!client->optlen); client->optlen = length; @@ -1306,7 +1296,7 @@ static int nbd_receive_request(QIOChannel *ioc, NBDRequest *request, uint32_t magic; int ret; - ret = nbd_read(ioc, buf, sizeof(buf), errp); + ret = nbd_read(ioc, buf, sizeof(buf), "request", errp); if (ret < 0) { return ret; } @@ -2111,8 +2101,9 @@ static int nbd_co_receive_request(NBDRequestData *req, NBDRequest *request, } } if (request->type == NBD_CMD_WRITE) { - if (nbd_read(client->ioc, req->data, request->len, errp) < 0) { - error_prepend(errp, "reading from socket failed: "); + if (nbd_read(client->ioc, req->data, request->len, "CMD_WRITE data", + errp) < 0) + { return -EIO; } req->complete = true; From 7f86068dc1aceec8f6151a3a713e57e680f73b45 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Fri, 1 Feb 2019 16:01:33 +0300 Subject: [PATCH 3/8] block/nbd-client: split channel errors from export errors To implement nbd reconnect in further patches, we need to distinguish error codes, returned by nbd server, from channel errors, to reconnect only in the latter case. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake Message-Id: <20190201130138.94525-2-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake --- block/nbd-client.c | 83 ++++++++++++++++++++++++++-------------------- 1 file changed, 47 insertions(+), 36 deletions(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index 57f679ad4d..fd58cda2f1 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -504,11 +504,11 @@ static coroutine_fn int nbd_co_do_receive_one_chunk( */ static coroutine_fn int nbd_co_receive_one_chunk( NBDClientSession *s, uint64_t handle, bool only_structured, - QEMUIOVector *qiov, NBDReply *reply, void **payload, Error **errp) + int *request_ret, QEMUIOVector *qiov, NBDReply *reply, void **payload, + Error **errp) { - int request_ret; int ret = nbd_co_do_receive_one_chunk(s, handle, only_structured, - &request_ret, qiov, payload, errp); + request_ret, qiov, payload, errp); if (ret < 0) { s->quit = true; @@ -518,7 +518,6 @@ static coroutine_fn int nbd_co_receive_one_chunk( *reply = s->reply; } s->reply.handle = 0; - ret = request_ret; } if (s->read_reply_co) { @@ -530,22 +529,17 @@ static coroutine_fn int nbd_co_receive_one_chunk( typedef struct NBDReplyChunkIter { int ret; - bool fatal; + int request_ret; Error *err; bool done, only_structured; } NBDReplyChunkIter; -static void nbd_iter_error(NBDReplyChunkIter *iter, bool fatal, - int ret, Error **local_err) +static void nbd_iter_channel_error(NBDReplyChunkIter *iter, + int ret, Error **local_err) { assert(ret < 0); - if ((fatal && !iter->fatal) || iter->ret == 0) { - if (iter->ret != 0) { - error_free(iter->err); - iter->err = NULL; - } - iter->fatal = fatal; + if (!iter->ret) { iter->ret = ret; error_propagate(&iter->err, *local_err); } else { @@ -555,6 +549,15 @@ static void nbd_iter_error(NBDReplyChunkIter *iter, bool fatal, *local_err = NULL; } +static void nbd_iter_request_error(NBDReplyChunkIter *iter, int ret) +{ + assert(ret < 0); + + if (!iter->request_ret) { + iter->request_ret = ret; + } +} + /* NBD_FOREACH_REPLY_CHUNK */ #define NBD_FOREACH_REPLY_CHUNK(s, iter, handle, structured, \ @@ -570,13 +573,13 @@ static bool nbd_reply_chunk_iter_receive(NBDClientSession *s, QEMUIOVector *qiov, NBDReply *reply, void **payload) { - int ret; + int ret, request_ret; NBDReply local_reply; NBDStructuredReplyChunk *chunk; Error *local_err = NULL; if (s->quit) { error_setg(&local_err, "Connection closed"); - nbd_iter_error(iter, true, -EIO, &local_err); + nbd_iter_channel_error(iter, -EIO, &local_err); goto break_loop; } @@ -590,10 +593,12 @@ static bool nbd_reply_chunk_iter_receive(NBDClientSession *s, } ret = nbd_co_receive_one_chunk(s, handle, iter->only_structured, - qiov, reply, payload, &local_err); + &request_ret, qiov, reply, payload, + &local_err); if (ret < 0) { - /* If it is a fatal error s->quit is set by nbd_co_receive_one_chunk */ - nbd_iter_error(iter, s->quit, ret, &local_err); + nbd_iter_channel_error(iter, ret, &local_err); + } else if (request_ret < 0) { + nbd_iter_request_error(iter, request_ret); } /* Do not execute the body of NBD_FOREACH_REPLY_CHUNK for simple reply. */ @@ -630,7 +635,7 @@ break_loop: } static int nbd_co_receive_return_code(NBDClientSession *s, uint64_t handle, - Error **errp) + int *request_ret, Error **errp) { NBDReplyChunkIter iter; @@ -639,12 +644,13 @@ static int nbd_co_receive_return_code(NBDClientSession *s, uint64_t handle, } error_propagate(errp, iter.err); + *request_ret = iter.request_ret; return iter.ret; } static int nbd_co_receive_cmdread_reply(NBDClientSession *s, uint64_t handle, uint64_t offset, QEMUIOVector *qiov, - Error **errp) + int *request_ret, Error **errp) { NBDReplyChunkIter iter; NBDReply reply; @@ -669,7 +675,7 @@ static int nbd_co_receive_cmdread_reply(NBDClientSession *s, uint64_t handle, offset, qiov, &local_err); if (ret < 0) { s->quit = true; - nbd_iter_error(&iter, true, ret, &local_err); + nbd_iter_channel_error(&iter, ret, &local_err); } break; default: @@ -679,7 +685,7 @@ static int nbd_co_receive_cmdread_reply(NBDClientSession *s, uint64_t handle, error_setg(&local_err, "Unexpected reply type: %d (%s) for CMD_READ", chunk->type, nbd_reply_type_lookup(chunk->type)); - nbd_iter_error(&iter, true, -EINVAL, &local_err); + nbd_iter_channel_error(&iter, -EINVAL, &local_err); } } @@ -688,12 +694,14 @@ static int nbd_co_receive_cmdread_reply(NBDClientSession *s, uint64_t handle, } error_propagate(errp, iter.err); + *request_ret = iter.request_ret; return iter.ret; } static int nbd_co_receive_blockstatus_reply(NBDClientSession *s, uint64_t handle, uint64_t length, - NBDExtent *extent, Error **errp) + NBDExtent *extent, + int *request_ret, Error **errp) { NBDReplyChunkIter iter; NBDReply reply; @@ -715,7 +723,7 @@ static int nbd_co_receive_blockstatus_reply(NBDClientSession *s, if (received) { s->quit = true; error_setg(&local_err, "Several BLOCK_STATUS chunks in reply"); - nbd_iter_error(&iter, true, -EINVAL, &local_err); + nbd_iter_channel_error(&iter, -EINVAL, &local_err); } received = true; @@ -724,7 +732,7 @@ static int nbd_co_receive_blockstatus_reply(NBDClientSession *s, &local_err); if (ret < 0) { s->quit = true; - nbd_iter_error(&iter, true, ret, &local_err); + nbd_iter_channel_error(&iter, ret, &local_err); } break; default: @@ -734,7 +742,7 @@ static int nbd_co_receive_blockstatus_reply(NBDClientSession *s, "Unexpected reply type: %d (%s) " "for CMD_BLOCK_STATUS", chunk->type, nbd_reply_type_lookup(chunk->type)); - nbd_iter_error(&iter, true, -EINVAL, &local_err); + nbd_iter_channel_error(&iter, -EINVAL, &local_err); } } @@ -749,14 +757,16 @@ static int nbd_co_receive_blockstatus_reply(NBDClientSession *s, iter.ret = -EIO; } } + error_propagate(errp, iter.err); + *request_ret = iter.request_ret; return iter.ret; } static int nbd_co_request(BlockDriverState *bs, NBDRequest *request, QEMUIOVector *write_qiov) { - int ret; + int ret, request_ret; Error *local_err = NULL; NBDClientSession *client = nbd_get_client_session(bs); @@ -772,7 +782,8 @@ static int nbd_co_request(BlockDriverState *bs, NBDRequest *request, return ret; } - ret = nbd_co_receive_return_code(client, request->handle, &local_err); + ret = nbd_co_receive_return_code(client, request->handle, + &request_ret, &local_err); if (local_err) { trace_nbd_co_request_fail(request->from, request->len, request->handle, request->flags, request->type, @@ -780,13 +791,13 @@ static int nbd_co_request(BlockDriverState *bs, NBDRequest *request, ret, error_get_pretty(local_err)); error_free(local_err); } - return ret; + return ret ? ret : request_ret; } int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags) { - int ret; + int ret, request_ret; Error *local_err = NULL; NBDClientSession *client = nbd_get_client_session(bs); NBDRequest request = { @@ -807,7 +818,7 @@ int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset, } ret = nbd_co_receive_cmdread_reply(client, request.handle, offset, qiov, - &local_err); + &request_ret, &local_err); if (local_err) { trace_nbd_co_request_fail(request.from, request.len, request.handle, request.flags, request.type, @@ -815,7 +826,7 @@ int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset, ret, error_get_pretty(local_err)); error_free(local_err); } - return ret; + return ret ? ret : request_ret; } int nbd_client_co_pwritev(BlockDriverState *bs, uint64_t offset, @@ -909,7 +920,7 @@ int coroutine_fn nbd_client_co_block_status(BlockDriverState *bs, int64_t *pnum, int64_t *map, BlockDriverState **file) { - int64_t ret; + int ret, request_ret; NBDExtent extent = { 0 }; NBDClientSession *client = nbd_get_client_session(bs); Error *local_err = NULL; @@ -934,7 +945,7 @@ int coroutine_fn nbd_client_co_block_status(BlockDriverState *bs, } ret = nbd_co_receive_blockstatus_reply(client, request.handle, bytes, - &extent, &local_err); + &extent, &request_ret, &local_err); if (local_err) { trace_nbd_co_request_fail(request.from, request.len, request.handle, request.flags, request.type, @@ -942,8 +953,8 @@ int coroutine_fn nbd_client_co_block_status(BlockDriverState *bs, ret, error_get_pretty(local_err)); error_free(local_err); } - if (ret < 0) { - return ret; + if (ret < 0 || request_ret < 0) { + return ret ? ret : request_ret; } assert(extent.length); From d42f78e9400c51f1ae30dadd52995e4d6b052d89 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Fri, 1 Feb 2019 16:01:34 +0300 Subject: [PATCH 4/8] block/nbd: move connection code from block/nbd to block/nbd-client Keep all connection code in one file, to be able to implement reconnect in further patches. Signed-off-by: Vladimir Sementsov-Ogievskiy Message-Id: <20190201130138.94525-3-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake [eblake: format tweak] Signed-off-by: Eric Blake --- block/nbd-client.c | 38 ++++++++++++++++++++++++++++++++++++-- block/nbd-client.h | 2 +- block/nbd.c | 40 ++-------------------------------------- 3 files changed, 39 insertions(+), 41 deletions(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index fd58cda2f1..80dc8cff47 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -991,8 +991,29 @@ void nbd_client_close(BlockDriverState *bs) nbd_teardown_connection(bs); } +static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr, + Error **errp) +{ + QIOChannelSocket *sioc; + Error *local_err = NULL; + + sioc = qio_channel_socket_new(); + qio_channel_set_name(QIO_CHANNEL(sioc), "nbd-client"); + + qio_channel_socket_connect_sync(sioc, saddr, &local_err); + if (local_err) { + object_unref(OBJECT(sioc)); + error_propagate(errp, local_err); + return NULL; + } + + qio_channel_set_delay(QIO_CHANNEL(sioc), false); + + return sioc; +} + int nbd_client_init(BlockDriverState *bs, - QIOChannelSocket *sioc, + SocketAddress *saddr, const char *export, QCryptoTLSCreds *tlscreds, const char *hostname, @@ -1002,6 +1023,16 @@ int nbd_client_init(BlockDriverState *bs, NBDClientSession *client = nbd_get_client_session(bs); int ret; + /* + * establish TCP connection, return error if it fails + * TODO: Configurable retry-until-timeout behaviour. + */ + QIOChannelSocket *sioc = nbd_establish_connection(saddr, errp); + + if (!sioc) { + return -ECONNREFUSED; + } + /* NBD handshake */ logout("session init %s\n", export); qio_channel_set_blocking(QIO_CHANNEL(sioc), true, NULL); @@ -1017,6 +1048,7 @@ int nbd_client_init(BlockDriverState *bs, g_free(client->info.name); if (ret < 0) { logout("Failed to negotiate with the NBD server\n"); + object_unref(OBJECT(sioc)); return ret; } if (x_dirty_bitmap && !client->info.base_allocation) { @@ -1042,7 +1074,6 @@ int nbd_client_init(BlockDriverState *bs, qemu_co_mutex_init(&client->send_mutex); qemu_co_queue_init(&client->free_sema); client->sioc = sioc; - object_ref(OBJECT(client->sioc)); if (!client->ioc) { client->ioc = QIO_CHANNEL(sioc); @@ -1068,6 +1099,9 @@ int nbd_client_init(BlockDriverState *bs, NBDRequest request = { .type = NBD_CMD_DISC }; nbd_send_request(client->ioc ?: QIO_CHANNEL(sioc), &request); + + object_unref(OBJECT(sioc)); + return ret; } } diff --git a/block/nbd-client.h b/block/nbd-client.h index cfc90550b9..2f047ba614 100644 --- a/block/nbd-client.h +++ b/block/nbd-client.h @@ -41,7 +41,7 @@ typedef struct NBDClientSession { NBDClientSession *nbd_get_client_session(BlockDriverState *bs); int nbd_client_init(BlockDriverState *bs, - QIOChannelSocket *sock, + SocketAddress *saddr, const char *export_name, QCryptoTLSCreds *tlscreds, const char *hostname, diff --git a/block/nbd.c b/block/nbd.c index e87699fb73..9db5eded89 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -295,30 +295,6 @@ NBDClientSession *nbd_get_client_session(BlockDriverState *bs) return &s->client; } -static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr, - Error **errp) -{ - QIOChannelSocket *sioc; - Error *local_err = NULL; - - sioc = qio_channel_socket_new(); - qio_channel_set_name(QIO_CHANNEL(sioc), "nbd-client"); - - qio_channel_socket_connect_sync(sioc, - saddr, - &local_err); - if (local_err) { - object_unref(OBJECT(sioc)); - error_propagate(errp, local_err); - return NULL; - } - - qio_channel_set_delay(QIO_CHANNEL(sioc), false); - - return sioc; -} - - static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp) { Object *obj; @@ -394,7 +370,6 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags, BDRVNBDState *s = bs->opaque; QemuOpts *opts = NULL; Error *local_err = NULL; - QIOChannelSocket *sioc = NULL; QCryptoTLSCreds *tlscreds = NULL; const char *hostname = NULL; int ret = -EINVAL; @@ -434,22 +409,11 @@ static int nbd_open(BlockDriverState *bs, QDict *options, int flags, hostname = s->saddr->u.inet.host; } - /* establish TCP connection, return error if it fails - * TODO: Configurable retry-until-timeout behaviour. - */ - sioc = nbd_establish_connection(s->saddr, errp); - if (!sioc) { - ret = -ECONNREFUSED; - goto error; - } - /* NBD handshake */ - ret = nbd_client_init(bs, sioc, s->export, tlscreds, hostname, + ret = nbd_client_init(bs, s->saddr, s->export, tlscreds, hostname, qemu_opt_get(opts, "x-dirty-bitmap"), errp); + error: - if (sioc) { - object_unref(OBJECT(sioc)); - } if (tlscreds) { object_unref(OBJECT(tlscreds)); } From b0e4b5a58fde6c0ed9edb9b683cfbbd8ab45c35d Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Fri, 1 Feb 2019 16:01:35 +0300 Subject: [PATCH 5/8] block/nbd-client: split connection from initialization Split connection code to reuse it for reconnect. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake Message-Id: <20190201130138.94525-4-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake --- block/nbd-client.c | 33 ++++++++++++++++++++++++--------- 1 file changed, 24 insertions(+), 9 deletions(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index 80dc8cff47..d7d8829769 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -1012,13 +1012,13 @@ static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr, return sioc; } -int nbd_client_init(BlockDriverState *bs, - SocketAddress *saddr, - const char *export, - QCryptoTLSCreds *tlscreds, - const char *hostname, - const char *x_dirty_bitmap, - Error **errp) +static int nbd_client_connect(BlockDriverState *bs, + SocketAddress *saddr, + const char *export, + QCryptoTLSCreds *tlscreds, + const char *hostname, + const char *x_dirty_bitmap, + Error **errp) { NBDClientSession *client = nbd_get_client_session(bs); int ret; @@ -1071,8 +1071,6 @@ int nbd_client_init(BlockDriverState *bs, bs->supported_zero_flags |= BDRV_REQ_MAY_UNMAP; } - qemu_co_mutex_init(&client->send_mutex); - qemu_co_queue_init(&client->free_sema); client->sioc = sioc; if (!client->ioc) { @@ -1105,3 +1103,20 @@ int nbd_client_init(BlockDriverState *bs, return ret; } } + +int nbd_client_init(BlockDriverState *bs, + SocketAddress *saddr, + const char *export, + QCryptoTLSCreds *tlscreds, + const char *hostname, + const char *x_dirty_bitmap, + Error **errp) +{ + NBDClientSession *client = nbd_get_client_session(bs); + + qemu_co_mutex_init(&client->send_mutex); + qemu_co_queue_init(&client->free_sema); + + return nbd_client_connect(bs, saddr, export, tlscreds, hostname, + x_dirty_bitmap, errp); +} From 65e01d47653eb127fa917bd9d2f1824a00ab2de6 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Fri, 1 Feb 2019 16:01:36 +0300 Subject: [PATCH 6/8] block/nbd-client: fix nbd_reply_chunk_iter_receive Use exported report, not the variable to be reused (should not really matter). Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake Message-Id: <20190201130138.94525-5-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake --- block/nbd-client.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index d7d8829769..65e5600068 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -602,7 +602,7 @@ static bool nbd_reply_chunk_iter_receive(NBDClientSession *s, } /* Do not execute the body of NBD_FOREACH_REPLY_CHUNK for simple reply. */ - if (nbd_reply_is_simple(&s->reply) || s->quit) { + if (nbd_reply_is_simple(reply) || s->quit) { goto break_loop; } From 88ed4e1bf0c7017c04fac2166ec9a7687aa21f97 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Fri, 1 Feb 2019 16:01:37 +0300 Subject: [PATCH 7/8] block/nbd-client: don't check ioc We have several paranoid checks for ioc != NULL. But ioc may become NULL only on close, which should not happen during requests handling. Also, we check ioc only sometimes, not after each yield, which is inconsistent. Let's drop these checks. However, for safety, let's leave asserts instead. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake Message-Id: <20190201130138.94525-6-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake --- block/nbd-client.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index 65e5600068..386c3feb14 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -53,9 +53,7 @@ static void nbd_teardown_connection(BlockDriverState *bs) { NBDClientSession *client = nbd_get_client_session(bs); - if (!client->ioc) { /* Already closed */ - return; - } + assert(client->ioc); /* finish any pending coroutines */ qio_channel_shutdown(client->ioc, @@ -154,10 +152,7 @@ static int nbd_co_send_request(BlockDriverState *bs, rc = -EIO; goto err; } - if (!s->ioc) { - rc = -EPIPE; - goto err; - } + assert(s->ioc); if (qiov) { qio_channel_set_cork(s->ioc, true); @@ -429,10 +424,11 @@ static coroutine_fn int nbd_co_do_receive_one_chunk( s->requests[i].receiving = true; qemu_coroutine_yield(); s->requests[i].receiving = false; - if (!s->ioc || s->quit) { + if (s->quit) { error_setg(errp, "Connection closed"); return -EIO; } + assert(s->ioc); assert(s->reply.handle == handle); @@ -982,9 +978,7 @@ void nbd_client_close(BlockDriverState *bs) NBDClientSession *client = nbd_get_client_session(bs); NBDRequest request = { .type = NBD_CMD_DISC }; - if (client->ioc == NULL) { - return; - } + assert(client->ioc); nbd_send_request(client->ioc, &request); From bc5a03350c220698229e7d6929dd242d5d358345 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Fri, 1 Feb 2019 16:01:38 +0300 Subject: [PATCH 8/8] block/nbd-client: rename read_reply_co to connection_co This coroutine will serve nbd reconnects, so, rename it to be something more generic. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake Message-Id: <20190201130138.94525-7-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake --- block/nbd-client.c | 24 ++++++++++++------------ block/nbd-client.h | 4 ++-- 2 files changed, 14 insertions(+), 14 deletions(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index 386c3feb14..f0ad54ce21 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -59,7 +59,7 @@ static void nbd_teardown_connection(BlockDriverState *bs) qio_channel_shutdown(client->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL); - BDRV_POLL_WHILE(bs, client->read_reply_co); + BDRV_POLL_WHILE(bs, client->connection_co); nbd_client_detach_aio_context(bs); object_unref(OBJECT(client->sioc)); @@ -68,7 +68,7 @@ static void nbd_teardown_connection(BlockDriverState *bs) client->ioc = NULL; } -static coroutine_fn void nbd_read_reply_entry(void *opaque) +static coroutine_fn void nbd_connection_entry(void *opaque) { NBDClientSession *s = opaque; uint64_t i; @@ -100,14 +100,14 @@ static coroutine_fn void nbd_read_reply_entry(void *opaque) } /* We're woken up again by the request itself. Note that there - * is no race between yielding and reentering read_reply_co. This + * is no race between yielding and reentering connection_co. This * is because: * * - if the request runs on the same AioContext, it is only * entered after we yield * * - if the request runs on a different AioContext, reentering - * read_reply_co happens through a bottom half, which can only + * connection_co happens through a bottom half, which can only * run after we yield. */ aio_co_wake(s->requests[i].coroutine); @@ -116,7 +116,7 @@ static coroutine_fn void nbd_read_reply_entry(void *opaque) s->quit = true; nbd_recv_coroutines_wake_all(s); - s->read_reply_co = NULL; + s->connection_co = NULL; aio_wait_kick(); } @@ -420,7 +420,7 @@ static coroutine_fn int nbd_co_do_receive_one_chunk( } *request_ret = 0; - /* Wait until we're woken up by nbd_read_reply_entry. */ + /* Wait until we're woken up by nbd_connection_entry. */ s->requests[i].receiving = true; qemu_coroutine_yield(); s->requests[i].receiving = false; @@ -495,7 +495,7 @@ static coroutine_fn int nbd_co_do_receive_one_chunk( } /* nbd_co_receive_one_chunk - * Read reply, wake up read_reply_co and set s->quit if needed. + * Read reply, wake up connection_co and set s->quit if needed. * Return value is a fatal error code or normal nbd reply error code */ static coroutine_fn int nbd_co_receive_one_chunk( @@ -509,15 +509,15 @@ static coroutine_fn int nbd_co_receive_one_chunk( if (ret < 0) { s->quit = true; } else { - /* For assert at loop start in nbd_read_reply_entry */ + /* For assert at loop start in nbd_connection_entry */ if (reply) { *reply = s->reply; } s->reply.handle = 0; } - if (s->read_reply_co) { - aio_co_wake(s->read_reply_co); + if (s->connection_co) { + aio_co_wake(s->connection_co); } return ret; @@ -970,7 +970,7 @@ void nbd_client_attach_aio_context(BlockDriverState *bs, { NBDClientSession *client = nbd_get_client_session(bs); qio_channel_attach_aio_context(QIO_CHANNEL(client->ioc), new_context); - aio_co_schedule(new_context, client->read_reply_co); + aio_co_schedule(new_context, client->connection_co); } void nbd_client_close(BlockDriverState *bs) @@ -1075,7 +1075,7 @@ static int nbd_client_connect(BlockDriverState *bs, /* Now that we're connected, set the socket to be non-blocking and * kick the reply mechanism. */ qio_channel_set_blocking(QIO_CHANNEL(sioc), false, NULL); - client->read_reply_co = qemu_coroutine_create(nbd_read_reply_entry, client); + client->connection_co = qemu_coroutine_create(nbd_connection_entry, client); nbd_client_attach_aio_context(bs, bdrv_get_aio_context(bs)); logout("Established connection with NBD server\n"); diff --git a/block/nbd-client.h b/block/nbd-client.h index 2f047ba614..d990207a5c 100644 --- a/block/nbd-client.h +++ b/block/nbd-client.h @@ -20,7 +20,7 @@ typedef struct { Coroutine *coroutine; uint64_t offset; /* original offset of the request */ - bool receiving; /* waiting for read_reply_co? */ + bool receiving; /* waiting for connection_co? */ } NBDClientRequest; typedef struct NBDClientSession { @@ -30,7 +30,7 @@ typedef struct NBDClientSession { CoMutex send_mutex; CoQueue free_sema; - Coroutine *read_reply_co; + Coroutine *connection_co; int in_flight; NBDClientRequest requests[MAX_NBD_REQUESTS];