| Message ID | 20210207151259.803917-1-arseny.krasnov@kaspersky.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | virtio/vsock: introduce SOCK_SEQPACKET support | expand |
On Sun, Feb 07, 2021 at 06:12:56PM +0300, Arseny Krasnov wrote: > This patchset impelements support of SOCK_SEQPACKET for virtio > transport. > As SOCK_SEQPACKET guarantees to save record boundaries, so to > do it, two new packet operations were added: first for start of record > and second to mark end of record(SEQ_BEGIN and SEQ_END later). Also, > both operations carries metadata - to maintain boundaries and payload > integrity. Metadata is introduced by adding special header with two > fields - message count and message length: > > struct virtio_vsock_seq_hdr { > __le32 msg_cnt; > __le32 msg_len; > } __attribute__((packed)); > > This header is transmitted as payload of SEQ_BEGIN and SEQ_END > packets(buffer of second virtio descriptor in chain) in the same way as > data transmitted in RW packets. Payload was chosen as buffer for this > header to avoid touching first virtio buffer which carries header of > packet, because someone could check that size of this buffer is equal > to size of packet header. To send record, packet with start marker is > sent first(it's header contains length of record and counter), then > counter is incremented and all data is sent as usual 'RW' packets and > finally SEQ_END is sent(it also carries counter of message, which is > counter of SEQ_BEGIN + 1), also after sedning SEQ_END counter is > incremented again. On receiver's side, length of record is known from > packet with start record marker. To check that no packets were dropped > by transport, counters of two sequential SEQ_BEGIN and SEQ_END are > checked(counter of SEQ_END must be bigger that counter of SEQ_BEGIN by > 1) and length of data between two markers is compared to length in > SEQ_BEGIN header. > Now as packets of one socket are not reordered neither on > vsock nor on vhost transport layers, such markers allows to restore > original record on receiver's side. If user's buffer is smaller that > record length, when all out of size data is dropped. > Maximum length of datagram is not limited as in stream socket, > because same credit logic is used. Difference with stream socket is > that user is not woken up until whole record is received or error > occurred. Implementation also supports 'MSG_EOR' and 'MSG_TRUNC' flags. > Tests also implemented. > > Arseny Krasnov (17): > af_vsock: update functions for connectible socket > af_vsock: separate wait data loop > af_vsock: separate receive data loop > af_vsock: implement SEQPACKET receive loop > af_vsock: separate wait space loop > af_vsock: implement send logic for SEQPACKET > af_vsock: rest of SEQPACKET support > af_vsock: update comments for stream sockets > virtio/vsock: dequeue callback for SOCK_SEQPACKET > virtio/vsock: fetch length for SEQPACKET record > virtio/vsock: add SEQPACKET receive logic > virtio/vsock: rest of SOCK_SEQPACKET support > virtio/vsock: setup SEQPACKET ops for transport > vhost/vsock: setup SEQPACKET ops for transport > vsock_test: add SOCK_SEQPACKET tests > loopback/vsock: setup SEQPACKET ops for transport > virtio/vsock: simplify credit update function API > > drivers/vhost/vsock.c | 8 +- > include/linux/virtio_vsock.h | 15 + > include/net/af_vsock.h | 9 + > include/uapi/linux/virtio_vsock.h | 16 + > net/vmw_vsock/af_vsock.c | 588 +++++++++++++++------- > net/vmw_vsock/virtio_transport.c | 5 + > net/vmw_vsock/virtio_transport_common.c | 316 ++++++++++-- > net/vmw_vsock/vsock_loopback.c | 5 + > tools/testing/vsock/util.c | 32 +- > tools/testing/vsock/util.h | 3 + > tools/testing/vsock/vsock_test.c | 126 +++++ > 11 files changed, 895 insertions(+), 228 deletions(-) > > TODO: > - What to do, when server doesn't support SOCK_SEQPACKET. In current > implementation RST is replied in the same way when listening port > is not found. I think that current RST is enough,because case when > server doesn't support SEQ_PACKET is same when listener missed(e.g. > no listener in both cases). - virtio spec patch > v3 -> v4: > - callbacks for loopback transport > - SEQPACKET specific metadata moved from packet header to payload > and called 'virtio_vsock_seq_hdr' > - record integrity check: > 1) SEQ_END operation was added, which marks end of record. > 2) Both SEQ_BEGIN and SEQ_END carries counter which is incremented > on every marker send. > - af_vsock.c: socket operations for STREAM and SEQPACKET call same > functions instead of having own "gates" differs only by names: > 'vsock_seqpacket/stream_getsockopt()' now replaced with > 'vsock_connectible_getsockopt()'. > - af_vsock.c: 'seqpacket_dequeue' callback returns error and flag that > record ready. There is no need to return number of copied bytes, > because case when record received successfully is checked at virtio > transport layer, when SEQ_END is processed. Also user doesn't need > number of copied bytes, because 'recv()' from SEQPACKET could return > error, length of users's buffer or length of whole record(both are > known in af_vsock.c). > - af_vsock.c: both wait loops in af_vsock.c(for data and space) moved > to separate functions because now both called from several places. > - af_vsock.c: 'vsock_assign_transport()' checks that 'new_transport' > pointer is not NULL and returns 'ESOCKTNOSUPPORT' instead of 'ENODEV' > if failed to use transport. > - tools/testing/vsock/vsock_test.c: rename tests > > v2 -> v3: > - patches reorganized: split for prepare and implementation patches > - local variables are declared in "Reverse Christmas tree" manner > - virtio_transport_common.c: valid leXX_to_cpu() for vsock header > fields access > - af_vsock.c: 'vsock_connectible_*sockopt()' added as shared code > between stream and seqpacket sockets. > - af_vsock.c: loops in '__vsock_*_recvmsg()' refactored. > - af_vsock.c: 'vsock_wait_data()' refactored. > > v1 -> v2: > - patches reordered: af_vsock.c related changes now before virtio vsock > - patches reorganized: more small patches, where +/- are not mixed > - tests for SOCK_SEQPACKET added > - all commit messages updated > - af_vsock.c: 'vsock_pre_recv_check()' inlined to > 'vsock_connectible_recvmsg()' > - af_vsock.c: 'vsock_assign_transport()' returns ENODEV if transport > was not found > - virtio_transport_common.c: transport callback for seqpacket dequeue > - virtio_transport_common.c: simplified > 'virtio_transport_recv_connected()' > - virtio_transport_common.c: send reset on socket and packet type > mismatch. > > -- > 2.25.1
On 07.02.2021 19:20, Michael S. Tsirkin wrote: > On Sun, Feb 07, 2021 at 06:12:56PM +0300, Arseny Krasnov wrote: >> This patchset impelements support of SOCK_SEQPACKET for virtio >> transport. >> As SOCK_SEQPACKET guarantees to save record boundaries, so to >> do it, two new packet operations were added: first for start of record >> and second to mark end of record(SEQ_BEGIN and SEQ_END later). Also, >> both operations carries metadata - to maintain boundaries and payload >> integrity. Metadata is introduced by adding special header with two >> fields - message count and message length: >> >> struct virtio_vsock_seq_hdr { >> __le32 msg_cnt; >> __le32 msg_len; >> } __attribute__((packed)); >> >> This header is transmitted as payload of SEQ_BEGIN and SEQ_END >> packets(buffer of second virtio descriptor in chain) in the same way as >> data transmitted in RW packets. Payload was chosen as buffer for this >> header to avoid touching first virtio buffer which carries header of >> packet, because someone could check that size of this buffer is equal >> to size of packet header. To send record, packet with start marker is >> sent first(it's header contains length of record and counter), then >> counter is incremented and all data is sent as usual 'RW' packets and >> finally SEQ_END is sent(it also carries counter of message, which is >> counter of SEQ_BEGIN + 1), also after sedning SEQ_END counter is >> incremented again. On receiver's side, length of record is known from >> packet with start record marker. To check that no packets were dropped >> by transport, counters of two sequential SEQ_BEGIN and SEQ_END are >> checked(counter of SEQ_END must be bigger that counter of SEQ_BEGIN by >> 1) and length of data between two markers is compared to length in >> SEQ_BEGIN header. >> Now as packets of one socket are not reordered neither on >> vsock nor on vhost transport layers, such markers allows to restore >> original record on receiver's side. If user's buffer is smaller that >> record length, when all out of size data is dropped. >> Maximum length of datagram is not limited as in stream socket, >> because same credit logic is used. Difference with stream socket is >> that user is not woken up until whole record is received or error >> occurred. Implementation also supports 'MSG_EOR' and 'MSG_TRUNC' flags. >> Tests also implemented. >> >> Arseny Krasnov (17): >> af_vsock: update functions for connectible socket >> af_vsock: separate wait data loop >> af_vsock: separate receive data loop >> af_vsock: implement SEQPACKET receive loop >> af_vsock: separate wait space loop >> af_vsock: implement send logic for SEQPACKET >> af_vsock: rest of SEQPACKET support >> af_vsock: update comments for stream sockets >> virtio/vsock: dequeue callback for SOCK_SEQPACKET >> virtio/vsock: fetch length for SEQPACKET record >> virtio/vsock: add SEQPACKET receive logic >> virtio/vsock: rest of SOCK_SEQPACKET support >> virtio/vsock: setup SEQPACKET ops for transport >> vhost/vsock: setup SEQPACKET ops for transport >> vsock_test: add SOCK_SEQPACKET tests >> loopback/vsock: setup SEQPACKET ops for transport >> virtio/vsock: simplify credit update function API >> >> drivers/vhost/vsock.c | 8 +- >> include/linux/virtio_vsock.h | 15 + >> include/net/af_vsock.h | 9 + >> include/uapi/linux/virtio_vsock.h | 16 + >> net/vmw_vsock/af_vsock.c | 588 +++++++++++++++------- >> net/vmw_vsock/virtio_transport.c | 5 + >> net/vmw_vsock/virtio_transport_common.c | 316 ++++++++++-- >> net/vmw_vsock/vsock_loopback.c | 5 + >> tools/testing/vsock/util.c | 32 +- >> tools/testing/vsock/util.h | 3 + >> tools/testing/vsock/vsock_test.c | 126 +++++ >> 11 files changed, 895 insertions(+), 228 deletions(-) >> >> TODO: >> - What to do, when server doesn't support SOCK_SEQPACKET. In current >> implementation RST is replied in the same way when listening port >> is not found. I think that current RST is enough,because case when >> server doesn't support SEQ_PACKET is same when listener missed(e.g. >> no listener in both cases). > - virtio spec patch Ok > >> v3 -> v4: >> - callbacks for loopback transport >> - SEQPACKET specific metadata moved from packet header to payload >> and called 'virtio_vsock_seq_hdr' >> - record integrity check: >> 1) SEQ_END operation was added, which marks end of record. >> 2) Both SEQ_BEGIN and SEQ_END carries counter which is incremented >> on every marker send. >> - af_vsock.c: socket operations for STREAM and SEQPACKET call same >> functions instead of having own "gates" differs only by names: >> 'vsock_seqpacket/stream_getsockopt()' now replaced with >> 'vsock_connectible_getsockopt()'. >> - af_vsock.c: 'seqpacket_dequeue' callback returns error and flag that >> record ready. There is no need to return number of copied bytes, >> because case when record received successfully is checked at virtio >> transport layer, when SEQ_END is processed. Also user doesn't need >> number of copied bytes, because 'recv()' from SEQPACKET could return >> error, length of users's buffer or length of whole record(both are >> known in af_vsock.c). >> - af_vsock.c: both wait loops in af_vsock.c(for data and space) moved >> to separate functions because now both called from several places. >> - af_vsock.c: 'vsock_assign_transport()' checks that 'new_transport' >> pointer is not NULL and returns 'ESOCKTNOSUPPORT' instead of 'ENODEV' >> if failed to use transport. >> - tools/testing/vsock/vsock_test.c: rename tests >> >> v2 -> v3: >> - patches reorganized: split for prepare and implementation patches >> - local variables are declared in "Reverse Christmas tree" manner >> - virtio_transport_common.c: valid leXX_to_cpu() for vsock header >> fields access >> - af_vsock.c: 'vsock_connectible_*sockopt()' added as shared code >> between stream and seqpacket sockets. >> - af_vsock.c: loops in '__vsock_*_recvmsg()' refactored. >> - af_vsock.c: 'vsock_wait_data()' refactored. >> >> v1 -> v2: >> - patches reordered: af_vsock.c related changes now before virtio vsock >> - patches reorganized: more small patches, where +/- are not mixed >> - tests for SOCK_SEQPACKET added >> - all commit messages updated >> - af_vsock.c: 'vsock_pre_recv_check()' inlined to >> 'vsock_connectible_recvmsg()' >> - af_vsock.c: 'vsock_assign_transport()' returns ENODEV if transport >> was not found >> - virtio_transport_common.c: transport callback for seqpacket dequeue >> - virtio_transport_common.c: simplified >> 'virtio_transport_recv_connected()' >> - virtio_transport_common.c: send reset on socket and packet type >> mismatch. >> >> -- >> 2.25.1 >
Hi Arseny, On Mon, Feb 08, 2021 at 09:32:59AM +0300, Arseny Krasnov wrote: > >On 07.02.2021 19:20, Michael S. Tsirkin wrote: >> On Sun, Feb 07, 2021 at 06:12:56PM +0300, Arseny Krasnov wrote: >>> This patchset impelements support of SOCK_SEQPACKET for virtio >>> transport. >>> As SOCK_SEQPACKET guarantees to save record boundaries, so to >>> do it, two new packet operations were added: first for start of record >>> and second to mark end of record(SEQ_BEGIN and SEQ_END later). Also, >>> both operations carries metadata - to maintain boundaries and payload >>> integrity. Metadata is introduced by adding special header with two >>> fields - message count and message length: >>> >>> struct virtio_vsock_seq_hdr { >>> __le32 msg_cnt; >>> __le32 msg_len; >>> } __attribute__((packed)); >>> >>> This header is transmitted as payload of SEQ_BEGIN and SEQ_END >>> packets(buffer of second virtio descriptor in chain) in the same way as >>> data transmitted in RW packets. Payload was chosen as buffer for this >>> header to avoid touching first virtio buffer which carries header of >>> packet, because someone could check that size of this buffer is equal >>> to size of packet header. To send record, packet with start marker is >>> sent first(it's header contains length of record and counter), then >>> counter is incremented and all data is sent as usual 'RW' packets and >>> finally SEQ_END is sent(it also carries counter of message, which is >>> counter of SEQ_BEGIN + 1), also after sedning SEQ_END counter is >>> incremented again. On receiver's side, length of record is known from >>> packet with start record marker. To check that no packets were dropped >>> by transport, counters of two sequential SEQ_BEGIN and SEQ_END are >>> checked(counter of SEQ_END must be bigger that counter of SEQ_BEGIN by >>> 1) and length of data between two markers is compared to length in >>> SEQ_BEGIN header. >>> Now as packets of one socket are not reordered neither on >>> vsock nor on vhost transport layers, such markers allows to restore >>> original record on receiver's side. If user's buffer is smaller that >>> record length, when all out of size data is dropped. >>> Maximum length of datagram is not limited as in stream socket, >>> because same credit logic is used. Difference with stream socket is >>> that user is not woken up until whole record is received or error >>> occurred. Implementation also supports 'MSG_EOR' and 'MSG_TRUNC' flags. >>> Tests also implemented. >>> >>> Arseny Krasnov (17): >>> af_vsock: update functions for connectible socket >>> af_vsock: separate wait data loop >>> af_vsock: separate receive data loop >>> af_vsock: implement SEQPACKET receive loop >>> af_vsock: separate wait space loop >>> af_vsock: implement send logic for SEQPACKET >>> af_vsock: rest of SEQPACKET support >>> af_vsock: update comments for stream sockets >>> virtio/vsock: dequeue callback for SOCK_SEQPACKET >>> virtio/vsock: fetch length for SEQPACKET record >>> virtio/vsock: add SEQPACKET receive logic >>> virtio/vsock: rest of SOCK_SEQPACKET support >>> virtio/vsock: setup SEQPACKET ops for transport >>> vhost/vsock: setup SEQPACKET ops for transport >>> vsock_test: add SOCK_SEQPACKET tests >>> loopback/vsock: setup SEQPACKET ops for transport >>> virtio/vsock: simplify credit update function API >>> >>> drivers/vhost/vsock.c | 8 +- >>> include/linux/virtio_vsock.h | 15 + >>> include/net/af_vsock.h | 9 + >>> include/uapi/linux/virtio_vsock.h | 16 + >>> net/vmw_vsock/af_vsock.c | 588 +++++++++++++++------- >>> net/vmw_vsock/virtio_transport.c | 5 + >>> net/vmw_vsock/virtio_transport_common.c | 316 ++++++++++-- >>> net/vmw_vsock/vsock_loopback.c | 5 + >>> tools/testing/vsock/util.c | 32 +- >>> tools/testing/vsock/util.h | 3 + >>> tools/testing/vsock/vsock_test.c | 126 +++++ >>> 11 files changed, 895 insertions(+), 228 deletions(-) >>> >>> TODO: >>> - What to do, when server doesn't support SOCK_SEQPACKET. In current >>> implementation RST is replied in the same way when listening port >>> is not found. I think that current RST is enough,because case when >>> server doesn't support SEQ_PACKET is same when listener missed(e.g. >>> no listener in both cases). I think is fine. >> - virtio spec patch >Ok Yes, please prepare a patch to discuss the VIRTIO spec changes. For example for 'virtio_vsock_seq_hdr', I left a comment about 'msg_cnt' naming that should be better to discuss with virtio guys. Anyway, I reviewed this series and I left some comments. I think we are in a good shape :-) Thanks, Stefano
On 11.02.2021 17:57, Stefano Garzarella wrote: > Hi Arseny, > > On Mon, Feb 08, 2021 at 09:32:59AM +0300, Arseny Krasnov wrote: >> On 07.02.2021 19:20, Michael S. Tsirkin wrote: >>> On Sun, Feb 07, 2021 at 06:12:56PM +0300, Arseny Krasnov wrote: >>>> This patchset impelements support of SOCK_SEQPACKET for virtio >>>> transport. >>>> As SOCK_SEQPACKET guarantees to save record boundaries, so to >>>> do it, two new packet operations were added: first for start of record >>>> and second to mark end of record(SEQ_BEGIN and SEQ_END later). Also, >>>> both operations carries metadata - to maintain boundaries and payload >>>> integrity. Metadata is introduced by adding special header with two >>>> fields - message count and message length: >>>> >>>> struct virtio_vsock_seq_hdr { >>>> __le32 msg_cnt; >>>> __le32 msg_len; >>>> } __attribute__((packed)); >>>> >>>> This header is transmitted as payload of SEQ_BEGIN and SEQ_END >>>> packets(buffer of second virtio descriptor in chain) in the same way as >>>> data transmitted in RW packets. Payload was chosen as buffer for this >>>> header to avoid touching first virtio buffer which carries header of >>>> packet, because someone could check that size of this buffer is equal >>>> to size of packet header. To send record, packet with start marker is >>>> sent first(it's header contains length of record and counter), then >>>> counter is incremented and all data is sent as usual 'RW' packets and >>>> finally SEQ_END is sent(it also carries counter of message, which is >>>> counter of SEQ_BEGIN + 1), also after sedning SEQ_END counter is >>>> incremented again. On receiver's side, length of record is known from >>>> packet with start record marker. To check that no packets were dropped >>>> by transport, counters of two sequential SEQ_BEGIN and SEQ_END are >>>> checked(counter of SEQ_END must be bigger that counter of SEQ_BEGIN by >>>> 1) and length of data between two markers is compared to length in >>>> SEQ_BEGIN header. >>>> Now as packets of one socket are not reordered neither on >>>> vsock nor on vhost transport layers, such markers allows to restore >>>> original record on receiver's side. If user's buffer is smaller that >>>> record length, when all out of size data is dropped. >>>> Maximum length of datagram is not limited as in stream socket, >>>> because same credit logic is used. Difference with stream socket is >>>> that user is not woken up until whole record is received or error >>>> occurred. Implementation also supports 'MSG_EOR' and 'MSG_TRUNC' flags. >>>> Tests also implemented. >>>> >>>> Arseny Krasnov (17): >>>> af_vsock: update functions for connectible socket >>>> af_vsock: separate wait data loop >>>> af_vsock: separate receive data loop >>>> af_vsock: implement SEQPACKET receive loop >>>> af_vsock: separate wait space loop >>>> af_vsock: implement send logic for SEQPACKET >>>> af_vsock: rest of SEQPACKET support >>>> af_vsock: update comments for stream sockets >>>> virtio/vsock: dequeue callback for SOCK_SEQPACKET >>>> virtio/vsock: fetch length for SEQPACKET record >>>> virtio/vsock: add SEQPACKET receive logic >>>> virtio/vsock: rest of SOCK_SEQPACKET support >>>> virtio/vsock: setup SEQPACKET ops for transport >>>> vhost/vsock: setup SEQPACKET ops for transport >>>> vsock_test: add SOCK_SEQPACKET tests >>>> loopback/vsock: setup SEQPACKET ops for transport >>>> virtio/vsock: simplify credit update function API >>>> >>>> drivers/vhost/vsock.c | 8 +- >>>> include/linux/virtio_vsock.h | 15 + >>>> include/net/af_vsock.h | 9 + >>>> include/uapi/linux/virtio_vsock.h | 16 + >>>> net/vmw_vsock/af_vsock.c | 588 +++++++++++++++------- >>>> net/vmw_vsock/virtio_transport.c | 5 + >>>> net/vmw_vsock/virtio_transport_common.c | 316 ++++++++++-- >>>> net/vmw_vsock/vsock_loopback.c | 5 + >>>> tools/testing/vsock/util.c | 32 +- >>>> tools/testing/vsock/util.h | 3 + >>>> tools/testing/vsock/vsock_test.c | 126 +++++ >>>> 11 files changed, 895 insertions(+), 228 deletions(-) >>>> >>>> TODO: >>>> - What to do, when server doesn't support SOCK_SEQPACKET. In current >>>> implementation RST is replied in the same way when listening port >>>> is not found. I think that current RST is enough,because case when >>>> server doesn't support SEQ_PACKET is same when listener missed(e.g. >>>> no listener in both cases). > I think is fine. > >>> - virtio spec patch >> Ok > Yes, please prepare a patch to discuss the VIRTIO spec changes. > > For example for 'virtio_vsock_seq_hdr', I left a comment about 'msg_cnt' > naming that should be better to discuss with virtio guys. Ok, i'll prepare it in v5. So I have to send it both LKML(as one of patches) and virtio mailing lists? (e.g. virtio-comment@lists.oasis-open.org) > > Anyway, I reviewed this series and I left some comments. > I think we are in a good shape :-) Great, thanks for review. I'll consider all review comments in next version. > > Thanks, > Stefano > >
On Fri, Feb 12, 2021 at 09:11:50AM +0300, Arseny Krasnov wrote: > >On 11.02.2021 17:57, Stefano Garzarella wrote: >> Hi Arseny, >> >> On Mon, Feb 08, 2021 at 09:32:59AM +0300, Arseny Krasnov wrote: >>> On 07.02.2021 19:20, Michael S. Tsirkin wrote: >>>> On Sun, Feb 07, 2021 at 06:12:56PM +0300, Arseny Krasnov wrote: >>>>> This patchset impelements support of SOCK_SEQPACKET for virtio >>>>> transport. >>>>> As SOCK_SEQPACKET guarantees to save record boundaries, so to >>>>> do it, two new packet operations were added: first for start of record >>>>> and second to mark end of record(SEQ_BEGIN and SEQ_END later). Also, >>>>> both operations carries metadata - to maintain boundaries and payload >>>>> integrity. Metadata is introduced by adding special header with two >>>>> fields - message count and message length: >>>>> >>>>> struct virtio_vsock_seq_hdr { >>>>> __le32 msg_cnt; >>>>> __le32 msg_len; >>>>> } __attribute__((packed)); >>>>> >>>>> This header is transmitted as payload of SEQ_BEGIN and SEQ_END >>>>> packets(buffer of second virtio descriptor in chain) in the same way as >>>>> data transmitted in RW packets. Payload was chosen as buffer for this >>>>> header to avoid touching first virtio buffer which carries header of >>>>> packet, because someone could check that size of this buffer is equal >>>>> to size of packet header. To send record, packet with start marker is >>>>> sent first(it's header contains length of record and counter), then >>>>> counter is incremented and all data is sent as usual 'RW' packets and >>>>> finally SEQ_END is sent(it also carries counter of message, which is >>>>> counter of SEQ_BEGIN + 1), also after sedning SEQ_END counter is >>>>> incremented again. On receiver's side, length of record is known from >>>>> packet with start record marker. To check that no packets were dropped >>>>> by transport, counters of two sequential SEQ_BEGIN and SEQ_END are >>>>> checked(counter of SEQ_END must be bigger that counter of SEQ_BEGIN by >>>>> 1) and length of data between two markers is compared to length in >>>>> SEQ_BEGIN header. >>>>> Now as packets of one socket are not reordered neither on >>>>> vsock nor on vhost transport layers, such markers allows to restore >>>>> original record on receiver's side. If user's buffer is smaller that >>>>> record length, when all out of size data is dropped. >>>>> Maximum length of datagram is not limited as in stream socket, >>>>> because same credit logic is used. Difference with stream socket is >>>>> that user is not woken up until whole record is received or error >>>>> occurred. Implementation also supports 'MSG_EOR' and 'MSG_TRUNC' flags. >>>>> Tests also implemented. >>>>> >>>>> Arseny Krasnov (17): >>>>> af_vsock: update functions for connectible socket >>>>> af_vsock: separate wait data loop >>>>> af_vsock: separate receive data loop >>>>> af_vsock: implement SEQPACKET receive loop >>>>> af_vsock: separate wait space loop >>>>> af_vsock: implement send logic for SEQPACKET >>>>> af_vsock: rest of SEQPACKET support >>>>> af_vsock: update comments for stream sockets >>>>> virtio/vsock: dequeue callback for SOCK_SEQPACKET >>>>> virtio/vsock: fetch length for SEQPACKET record >>>>> virtio/vsock: add SEQPACKET receive logic >>>>> virtio/vsock: rest of SOCK_SEQPACKET support >>>>> virtio/vsock: setup SEQPACKET ops for transport >>>>> vhost/vsock: setup SEQPACKET ops for transport >>>>> vsock_test: add SOCK_SEQPACKET tests >>>>> loopback/vsock: setup SEQPACKET ops for transport >>>>> virtio/vsock: simplify credit update function API >>>>> >>>>> drivers/vhost/vsock.c | 8 +- >>>>> include/linux/virtio_vsock.h | 15 + >>>>> include/net/af_vsock.h | 9 + >>>>> include/uapi/linux/virtio_vsock.h | 16 + >>>>> net/vmw_vsock/af_vsock.c | 588 +++++++++++++++------- >>>>> net/vmw_vsock/virtio_transport.c | 5 + >>>>> net/vmw_vsock/virtio_transport_common.c | 316 ++++++++++-- >>>>> net/vmw_vsock/vsock_loopback.c | 5 + >>>>> tools/testing/vsock/util.c | 32 +- >>>>> tools/testing/vsock/util.h | 3 + >>>>> tools/testing/vsock/vsock_test.c | 126 +++++ >>>>> 11 files changed, 895 insertions(+), 228 deletions(-) >>>>> >>>>> TODO: >>>>> - What to do, when server doesn't support SOCK_SEQPACKET. In current >>>>> implementation RST is replied in the same way when listening port >>>>> is not found. I think that current RST is enough,because case when >>>>> server doesn't support SEQ_PACKET is same when listener missed(e.g. >>>>> no listener in both cases). >> I think is fine. >> >>>> - virtio spec patch >>> Ok >> Yes, please prepare a patch to discuss the VIRTIO spec changes. >> >> For example for 'virtio_vsock_seq_hdr', I left a comment about 'msg_cnt' >> naming that should be better to discuss with virtio guys. > >Ok, i'll prepare it in v5. So I have to send it both LKML(as one of patches) and > >virtio mailing lists? (e.g. virtio-comment@lists.oasis-open.org) I think you can send the VIRTIO spec patch separately from this series to virtio-comment, maybe CCing virtualization@lists.linux-foundation.org But Michael could correct me :-) > >> >> Anyway, I reviewed this series and I left some comments. >> I think we are in a good shape :-) >Great, thanks for review. I'll consider all review comments in next >version. Great! Stefano
This patchset impelements support of SOCK_SEQPACKET for virtio transport. As SOCK_SEQPACKET guarantees to save record boundaries, so to do it, two new packet operations were added: first for start of record and second to mark end of record(SEQ_BEGIN and SEQ_END later). Also, both operations carries metadata - to maintain boundaries and payload integrity. Metadata is introduced by adding special header with two fields - message count and message length: struct virtio_vsock_seq_hdr { __le32 msg_cnt; __le32 msg_len; } __attribute__((packed)); This header is transmitted as payload of SEQ_BEGIN and SEQ_END packets(buffer of second virtio descriptor in chain) in the same way as data transmitted in RW packets. Payload was chosen as buffer for this header to avoid touching first virtio buffer which carries header of packet, because someone could check that size of this buffer is equal to size of packet header. To send record, packet with start marker is sent first(it's header contains length of record and counter), then counter is incremented and all data is sent as usual 'RW' packets and finally SEQ_END is sent(it also carries counter of message, which is counter of SEQ_BEGIN + 1), also after sedning SEQ_END counter is incremented again. On receiver's side, length of record is known from packet with start record marker. To check that no packets were dropped by transport, counters of two sequential SEQ_BEGIN and SEQ_END are checked(counter of SEQ_END must be bigger that counter of SEQ_BEGIN by 1) and length of data between two markers is compared to length in SEQ_BEGIN header. Now as packets of one socket are not reordered neither on vsock nor on vhost transport layers, such markers allows to restore original record on receiver's side. If user's buffer is smaller that record length, when all out of size data is dropped. Maximum length of datagram is not limited as in stream socket, because same credit logic is used. Difference with stream socket is that user is not woken up until whole record is received or error occurred. Implementation also supports 'MSG_EOR' and 'MSG_TRUNC' flags. Tests also implemented. Arseny Krasnov (17): af_vsock: update functions for connectible socket af_vsock: separate wait data loop af_vsock: separate receive data loop af_vsock: implement SEQPACKET receive loop af_vsock: separate wait space loop af_vsock: implement send logic for SEQPACKET af_vsock: rest of SEQPACKET support af_vsock: update comments for stream sockets virtio/vsock: dequeue callback for SOCK_SEQPACKET virtio/vsock: fetch length for SEQPACKET record virtio/vsock: add SEQPACKET receive logic virtio/vsock: rest of SOCK_SEQPACKET support virtio/vsock: setup SEQPACKET ops for transport vhost/vsock: setup SEQPACKET ops for transport vsock_test: add SOCK_SEQPACKET tests loopback/vsock: setup SEQPACKET ops for transport virtio/vsock: simplify credit update function API drivers/vhost/vsock.c | 8 +- include/linux/virtio_vsock.h | 15 + include/net/af_vsock.h | 9 + include/uapi/linux/virtio_vsock.h | 16 + net/vmw_vsock/af_vsock.c | 588 +++++++++++++++------- net/vmw_vsock/virtio_transport.c | 5 + net/vmw_vsock/virtio_transport_common.c | 316 ++++++++++-- net/vmw_vsock/vsock_loopback.c | 5 + tools/testing/vsock/util.c | 32 +- tools/testing/vsock/util.h | 3 + tools/testing/vsock/vsock_test.c | 126 +++++ 11 files changed, 895 insertions(+), 228 deletions(-) TODO: - What to do, when server doesn't support SOCK_SEQPACKET. In current implementation RST is replied in the same way when listening port is not found. I think that current RST is enough,because case when server doesn't support SEQ_PACKET is same when listener missed(e.g. no listener in both cases). v3 -> v4: - callbacks for loopback transport - SEQPACKET specific metadata moved from packet header to payload and called 'virtio_vsock_seq_hdr' - record integrity check: 1) SEQ_END operation was added, which marks end of record. 2) Both SEQ_BEGIN and SEQ_END carries counter which is incremented on every marker send. - af_vsock.c: socket operations for STREAM and SEQPACKET call same functions instead of having own "gates" differs only by names: 'vsock_seqpacket/stream_getsockopt()' now replaced with 'vsock_connectible_getsockopt()'. - af_vsock.c: 'seqpacket_dequeue' callback returns error and flag that record ready. There is no need to return number of copied bytes, because case when record received successfully is checked at virtio transport layer, when SEQ_END is processed. Also user doesn't need number of copied bytes, because 'recv()' from SEQPACKET could return error, length of users's buffer or length of whole record(both are known in af_vsock.c). - af_vsock.c: both wait loops in af_vsock.c(for data and space) moved to separate functions because now both called from several places. - af_vsock.c: 'vsock_assign_transport()' checks that 'new_transport' pointer is not NULL and returns 'ESOCKTNOSUPPORT' instead of 'ENODEV' if failed to use transport. - tools/testing/vsock/vsock_test.c: rename tests v2 -> v3: - patches reorganized: split for prepare and implementation patches - local variables are declared in "Reverse Christmas tree" manner - virtio_transport_common.c: valid leXX_to_cpu() for vsock header fields access - af_vsock.c: 'vsock_connectible_*sockopt()' added as shared code between stream and seqpacket sockets. - af_vsock.c: loops in '__vsock_*_recvmsg()' refactored. - af_vsock.c: 'vsock_wait_data()' refactored. v1 -> v2: - patches reordered: af_vsock.c related changes now before virtio vsock - patches reorganized: more small patches, where +/- are not mixed - tests for SOCK_SEQPACKET added - all commit messages updated - af_vsock.c: 'vsock_pre_recv_check()' inlined to 'vsock_connectible_recvmsg()' - af_vsock.c: 'vsock_assign_transport()' returns ENODEV if transport was not found - virtio_transport_common.c: transport callback for seqpacket dequeue - virtio_transport_common.c: simplified 'virtio_transport_recv_connected()' - virtio_transport_common.c: send reset on socket and packet type mismatch.