Hi all, Here is v9 of the RTRS (former IBTRS) RDMA Transport Library and the corresponding RNBD (former IBNBD) RDMA Network Block Device, which includes changes to address comments from the community. Introduction ------------- RTRS (RDMA Transport) is a reliable high speed transport library which allows for establishing connection between client and server machines via RDMA. It is based on RDMA-CM, so expect also to support RoCE and iWARP, but we mainly tested in IB environment. It is optimized to transfer (read/write) IO blocks in the sense that it follows the BIO semantics of providing the possibility to either write data from a scatter-gather list to the remote side or to request ("read") data transfer from the remote side into a given set of buffers. RTRS is multipath capable and provides I/O fail-over and load-balancing functionality, i.e. in RTRS terminology, an RTRS path is a set of RDMA connections and particular path is selected according to the load-balancing policy. It can be used for other components beside RNBD. Module parameter always_invalidate is introduced for the security problem discussed in LPC RDMA MC 2019. When always_invalidate=Y, on the server side we invalidate each rdma buffer before we hand it over to RNBD server and then pass it to the block layer. A new rkey is generated and registered for the buffer after it returns back from the block layer and RNBD server. The new rkey is sent back to the client along with the IO result. The procedure is the default behaviour of the driver. This invalidation and registration on each IO causes performance drop of up to 20%. A user of the driver may choose to load the modules with this mechanism switched off (always_invalidate=N), if he understands and can take the risk of a malicious client being able to corrupt memory of a server it is connected to. This might be a reasonable option in a scenario where all the clients and all the servers are located within a secure datacenter. RNBD (RDMA Network Block Device) is a pair of kernel modules (client and server) that allow for remote access of a block device on the server over RTRS protocol. After being mapped, the remote block devices can be accessed on the client side as local block devices. Internally RNBD uses RTRS as an RDMA transport library. Commits for kernel can be found here: https://github.com/ionos-enterprise/ibnbd/commits/linux-5.6-rc2-ibnbd-v9 Testing ------- All the changes have been tested with our regression testsuite in our staging environment in IONOS data center. it's around 200 testcases, for both always_invalidate=N and always_invalidate=Y configurations. Changelog --------- v9: o Rebased to linux-5.6-rc2 o Update Date/Kernel version in Documentation o Update description in Kconfig for RNBD o rtrs-clt: inline rtrs_clt_decrease_inflight o rtrs-clt: only track inflight for Min_inflight policy v8: o Rebased to linux-5.5-rc7 o Reviewed likey/unlikely usage, only keep the one in IO path suggested by Leon Romanovsky o Reviewed inline usage, remove inline for functions longer than 5 lines of code suggested by Leon o Removed 2 WARN_ON suggested by Leon o Removed 2 empty lines between copyright suggested by Leon o Makefile: remove compat include for upstream suggested by Leon o rtrs-clt: remove module parameters suggested by Leon o drop rnbd_clt_dev_is_mapped o rnbd-clt: clean up rnbd_rerun_if_needed o rtrs-srv: remove reset_all sysfs o rtrs stats: remove wc_completion stats o rtrs-clt: enhance doc for rtrs_clt_change_state o rtrs-clt: remove unused rtrs_permit_from_pdu * https://lore.kernel.org/linux-block/20200124204753.13154-1-jinpuwang@xxxxxxxxx/ v7: o Rebased to linux-5.5-rc6 o Implement code-style/readability/API/Documentation etc suggestions by Bart van Assche o Make W=1 clean o New benchmark results for Mellanox ConnectX-5 o second try adding MAINTAINERS entries in alphabetical order as Gal Pressman suggested * https://lore.kernel.org/linux-block/20200116125915.14815-1-jinpuwang@xxxxxxxxx/ v6: o Rebased to linux-5.5-rc4 o Fix typo in my email address in first patch o Cleanup copyright as suggested by Leon Romanovsky o Remove 2 redudant kobject_del in error path as suggested by Leon Romanovsky o Add MAINTAINERS entries in alphabetical order as Gal Pressman suggested * https://lore.kernel.org/linux-block/20191230102942.18395-1-jinpuwang@xxxxxxxxx/ v5: o Fix the security problem pointed out by Jason o Implement code-style/readability/API/etc suggestions by Bart van Assche o Rename IBTRS and IBNBD to RTRS and RNBD accordingly o Fileio mode support in rnbd-srv has been removed. * https://lore.kernel.org/linux-block/20191220155109.8959-1-jinpuwang@xxxxxxxxx/ v4: o Protocol extended to transport IO priorities o Support for Mellanox ConnectX-4/X-5 o Minor sysfs extentions (display access mode on server side) o Bug fixes: cleaning up sysfs folders, race on deallocation of resources o Style fixes * https://lore.kernel.org/linux-block/20190620150337.7847-1-jinpuwang@xxxxxxxxx/ v3: o Sparse fixes: - le32 -> le16 conversion - pcpu and RCU wrong declaration - sysfs: dynamically alloc array of sockaddr structures to reduce size of a stack frame o Rename sysfs folder on client and server sides to show source and destination addresses of the connection, i.e.: .../<session-name>/paths/<src@dst>/ o Remove external inclusions from Makefiles. * https://lore.kernel.org/linux-block/20180606152515.25807-1-roman.penyaev@xxxxxxxxxxxxxxxx/ v2: o IBNBD: - No legacy request IO mode, only MQ is left. o IBTRS: - No FMR registration, only FR is left. * https://lore.kernel.org/linux-block/20180518130413.16997-1-roman.penyaev@xxxxxxxxxxxxxxxx/ v1: o IBTRS: load-balancing and IO fail-over using multipath features were added. o Major parts of the code were rewritten, simplified and overall code size was reduced by a quarter. * https://lore.kernel.org/linux-block/20180202140904.2017-1-roman.penyaev@xxxxxxxxxxxxxxxx/ v0: o Initial submission * https://lore.kernel.org/linux-block/1490352343-20075-1-git-send-email-jinpu.wangl@xxxxxxxxxxxxxxxx/ As always, please review and share your comments, and consider to merge to upstream. Thanks. Jack Wang (25): sysfs: export sysfs_remove_file_self() RDMA/rtrs: public interface header to establish RDMA connections RDMA/rtrs: private headers with rtrs protocol structs and helpers RDMA/rtrs: core: lib functions shared between client and server modules RDMA/rtrs: client: private header with client structs and functions RDMA/rtrs: client: main functionality RDMA/rtrs: client: statistics functions RDMA/rtrs: client: sysfs interface functions RDMA/rtrs: server: private header with server structs and functions RDMA/rtrs: server: main functionality RDMA/rtrs: server: statistics functions RDMA/rtrs: server: sysfs interface functions RDMA/rtrs: include client and server modules into kernel compilation RDMA/rtrs: a bit of documentation block/rnbd: private headers with rnbd protocol structs and helpers block/rnbd: client: private header with client structs and functions block/rnbd: client: main functionality block/rnbd: client: sysfs interface functions block/rnbd: server: private header with server structs and functions block/rnbd: server: main functionality block/rnbd: server: functionality for IO submission to file or block dev block/rnbd: server: sysfs interface functions block/rnbd: include client and server modules into kernel compilation block/rnbd: a bit of documentation MAINTAINERS: Add maintainers for RNBD/RTRS modules Documentation/ABI/testing/sysfs-block-rnbd | 46 + .../ABI/testing/sysfs-class-rnbd-client | 111 + .../ABI/testing/sysfs-class-rnbd-server | 50 + .../ABI/testing/sysfs-class-rtrs-client | 131 + .../ABI/testing/sysfs-class-rtrs-server | 53 + MAINTAINERS | 14 + drivers/block/Kconfig | 2 + drivers/block/Makefile | 1 + drivers/block/rnbd/Kconfig | 28 + drivers/block/rnbd/Makefile | 15 + drivers/block/rnbd/README | 92 + drivers/block/rnbd/rnbd-clt-sysfs.c | 619 ++++ drivers/block/rnbd/rnbd-clt.c | 1721 ++++++++++ drivers/block/rnbd/rnbd-clt.h | 148 + drivers/block/rnbd/rnbd-common.c | 23 + drivers/block/rnbd/rnbd-log.h | 41 + drivers/block/rnbd/rnbd-proto.h | 305 ++ drivers/block/rnbd/rnbd-srv-dev.c | 142 + drivers/block/rnbd/rnbd-srv-dev.h | 110 + drivers/block/rnbd/rnbd-srv-sysfs.c | 211 ++ drivers/block/rnbd/rnbd-srv.c | 862 +++++ drivers/block/rnbd/rnbd-srv.h | 79 + drivers/infiniband/Kconfig | 1 + drivers/infiniband/ulp/Makefile | 1 + drivers/infiniband/ulp/rtrs/Kconfig | 27 + drivers/infiniband/ulp/rtrs/Makefile | 15 + drivers/infiniband/ulp/rtrs/README | 213 ++ drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c | 205 ++ drivers/infiniband/ulp/rtrs/rtrs-clt-sysfs.c | 480 +++ drivers/infiniband/ulp/rtrs/rtrs-clt.c | 2932 +++++++++++++++++ drivers/infiniband/ulp/rtrs/rtrs-clt.h | 250 ++ drivers/infiniband/ulp/rtrs/rtrs-log.h | 28 + drivers/infiniband/ulp/rtrs/rtrs-pri.h | 401 +++ drivers/infiniband/ulp/rtrs/rtrs-srv-stats.c | 47 + drivers/infiniband/ulp/rtrs/rtrs-srv-sysfs.c | 285 ++ drivers/infiniband/ulp/rtrs/rtrs-srv.c | 2164 ++++++++++++ drivers/infiniband/ulp/rtrs/rtrs-srv.h | 138 + drivers/infiniband/ulp/rtrs/rtrs.c | 594 ++++ drivers/infiniband/ulp/rtrs/rtrs.h | 310 ++ fs/sysfs/file.c | 1 + 40 files changed, 12896 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-block-rnbd create mode 100644 Documentation/ABI/testing/sysfs-class-rnbd-client create mode 100644 Documentation/ABI/testing/sysfs-class-rnbd-server create mode 100644 Documentation/ABI/testing/sysfs-class-rtrs-client create mode 100644 Documentation/ABI/testing/sysfs-class-rtrs-server create mode 100644 drivers/block/rnbd/Kconfig create mode 100644 drivers/block/rnbd/Makefile create mode 100644 drivers/block/rnbd/README create mode 100644 drivers/block/rnbd/rnbd-clt-sysfs.c create mode 100644 drivers/block/rnbd/rnbd-clt.c create mode 100644 drivers/block/rnbd/rnbd-clt.h create mode 100644 drivers/block/rnbd/rnbd-common.c create mode 100644 drivers/block/rnbd/rnbd-log.h create mode 100644 drivers/block/rnbd/rnbd-proto.h create mode 100644 drivers/block/rnbd/rnbd-srv-dev.c create mode 100644 drivers/block/rnbd/rnbd-srv-dev.h create mode 100644 drivers/block/rnbd/rnbd-srv-sysfs.c create mode 100644 drivers/block/rnbd/rnbd-srv.c create mode 100644 drivers/block/rnbd/rnbd-srv.h create mode 100644 drivers/infiniband/ulp/rtrs/Kconfig create mode 100644 drivers/infiniband/ulp/rtrs/Makefile create mode 100644 drivers/infiniband/ulp/rtrs/README create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-clt-sysfs.c create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-clt.c create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-clt.h create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-log.h create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-pri.h create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-srv-stats.c create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-srv-sysfs.c create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-srv.c create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-srv.h create mode 100644 drivers/infiniband/ulp/rtrs/rtrs.c create mode 100644 drivers/infiniband/ulp/rtrs/rtrs.h -- 2.17.1