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path: root/net/smc/smc_core.h
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2024-04-30net/smc: {at|de}tach sndbuf to peer DMB if supportedWen Gu
If the device used by SMC-D supports merging local sndbuf to peer DMB, then create sndbuf descriptor and attach it to peer DMB once peer token is obtained, and detach and free the sndbuf descriptor when the connection is freed. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com> Reviewed-and-tested-by: Jan Karcher <jaka@linux.ibm.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-12-26net/smc: compatible with 128-bits extended GID of virtual ISM deviceWen Gu
According to virtual ISM support feature defined by SMCv2.1, GIDs of virtual ISM device are UUIDs defined by RFC4122, which are 128-bits long. So some adaptation work is required. And note that the GIDs of existing platform firmware ISM devices still remain 64-bits long. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-26net/smc: support SMCv2.x supplemental features negotiationWen Gu
This patch adds SMCv2.x supplemental features negotiation. Supported SMCv2.x supplemental features are represented by feature_mask in FCE field. The negotiation process is as follows. Server Client Proposal(features(c-mask bits)) <----------------------------------------- Accept(features(s-mask bits)) -----------------------------------------> Confirm(features(s&c-mask bits)) <----------------------------------------- Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Reviewed-and-tested-by: Wenjia Zhang <wenjia@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-19net/smc: support max links per lgr negotiation in clc handshakeGuangguan Wang
Support max links per lgr negotiation in clc handshake for SMCR v2.1, which is one of smc v2.1 features. Server makes decision for the final value of max links based on the client preferred max links and self-preferred max links. Here use the minimum value of the client preferred max links and server preferred max links. Client Server Proposal(max links(client preferred)) --------------------------------------> Accept(max links(accepted value)) accepted value=min(client preferred, server preferred) <------------------------------------- Confirm(max links(accepted value)) -------------------------------------> Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com> Reviewed-by: Jan Karcher <jaka@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-19net/smc: support max connections per lgr negotiationGuangguan Wang
Support max connections per lgr negotiation for SMCR v2.1, which is one of smc v2.1 features. Server makes decision for the final value of max conns based on the client preferred max conns and self-preferred max conns. Here use the minimum value of client preferred max conns and server preferred max conns. Client Server Proposal(max conns(client preferred)) ------------------------------------> Accept(max conns(accepted value)) accepted value=min(client preferred, server preferred) <----------------------------------- Confirm(max conns(accepted value)) -----------------------------------> Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com> Reviewed-by: Jan Karcher <jaka@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-19net/smc: support smc release version negotiation in clc handshakeGuangguan Wang
Support smc release version negotiation in clc handshake based on SMC v2, where no negotiation process for different releases, but for different versions. The latest smc release version was updated to v2.1. And currently there are two release versions of SMCv2, v2.0 and v2.1. In the release version negotiation, client sends the preferred release version by CLC Proposal Message, server makes decision for which release version to use based on the client preferred release version and self-supported release version (here choose the minimum release version of the client preferred and server latest supported), then the decision returns to client by CLC Accept Message. Client confirms the decision by CLC Confirm Message. Client Server Proposal(preferred release version) ------------------------------------> Accept(accpeted release version) min(client preferred, server latest supported) <------------------------------------ Confirm(accpeted release version) ------------------------------------> Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com> Reviewed-by: Jan Karcher <jaka@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-31net/smc: Remove unused function declarationsYue Haibing
commit f9aab6f2ce57 ("net/smc: immediate freeing in smc_lgr_cleanup_early()") left behind smc_lgr_schedule_free_work_fast() declaration. And since commit 349d43127dac ("net/smc: fix kernel panic caused by race of smc_sock") smc_ib_modify_qp_reset() is not used anymore. Signed-off-by: Yue Haibing <yuehaibing@huawei.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com> Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com> Link: https://lore.kernel.org/r/20230729121929.17180-1-yuehaibing@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-17net/smc: Use percpu ref for wr tx referenceKai Shen
The refcount wr_tx_refcnt may cause cache thrashing problems among cores and we can use percpu ref to mitigate this issue here. We gain some performance improvement with percpu ref here on our customized smc-r verion. Applying cache alignment may also mitigate this problem but it seem more reasonable to use percpu ref here. We can also replace wr_reg_refcnt with one percpu reference like wr_tx_refcnt. redis-benchmark on smc-r with atomic wr_tx_refcnt: SET: 525707.06 requests per second, p50=0.087 msec GET: 554877.38 requests per second, p50=0.087 msec redis-benchmark on the percpu_ref version: SET: 540482.06 requests per second, p50=0.087 msec GET: 570711.12 requests per second, p50=0.079 msec Cases are like "redis-benchmark -h x.x.x.x -q -t set,get -P 1 -n 5000000 -c 50 -d 10 --threads 4". Signed-off-by: Kai Shen <KaiShen@linux.alibaba.com> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-04net/smc: replace mutex rmbs_lock and sndbufs_lock with rw_semaphoreD. Wythe
It's clear that rmbs_lock and sndbufs_lock are aims to protect the rmbs list or the sndbufs list. During connection establieshment, smc_buf_get_slot() will always be invoked, and it only performs read semantics in rmbs list and sndbufs list. Based on the above considerations, we replace mutex with rw_semaphore. Only smc_buf_get_slot() use down_read() to allow smc_buf_get_slot() run concurrently, other part use down_write() to keep exclusive semantics. Signed-off-by: D. Wythe <alibuda@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-04net/smc: llc_conf_mutex refactor, replace it with rw_semaphoreD. Wythe
llc_conf_mutex was used to protect links and link related configurations in the same link group, for example, add or delete links. However, in most cases, the protected critical area has only read semantics and with no write semantics at all, such as obtaining a usable link or an available rmb_desc. This patch do simply code refactoring, replace mutex with rw_semaphore, replace mutex_lock with down_write and replace mutex_unlock with up_write. Theoretically, this replacement is equivalent, but after this patch, we can distinguish lock granularity according to different semantics of critical areas. Signed-off-by: D. Wythe <alibuda@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-09-07net/smc: Fix possible access to freed memory in link clearYacan Liu
After modifying the QP to the Error state, all RX WR would be completed with WC in IB_WC_WR_FLUSH_ERR status. Current implementation does not wait for it is done, but destroy the QP and free the link group directly. So there is a risk that accessing the freed memory in tasklet context. Here is a crash example: BUG: unable to handle page fault for address: ffffffff8f220860 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD f7300e067 P4D f7300e067 PUD f7300f063 PMD 8c4e45063 PTE 800ffff08c9df060 Oops: 0002 [#1] SMP PTI CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: G S OE 5.10.0-0607+ #23 Hardware name: Inspur NF5280M4/YZMB-00689-101, BIOS 4.1.20 07/09/2018 RIP: 0010:native_queued_spin_lock_slowpath+0x176/0x1b0 Code: f3 90 48 8b 32 48 85 f6 74 f6 eb d5 c1 ee 12 83 e0 03 83 ee 01 48 c1 e0 05 48 63 f6 48 05 00 c8 02 00 48 03 04 f5 00 09 98 8e <48> 89 10 8b 42 08 85 c0 75 09 f3 90 8b 42 08 85 c0 74 f7 48 8b 32 RSP: 0018:ffffb3b6c001ebd8 EFLAGS: 00010086 RAX: ffffffff8f220860 RBX: 0000000000000246 RCX: 0000000000080000 RDX: ffff91db1f86c800 RSI: 000000000000173c RDI: ffff91db62bace00 RBP: ffff91db62bacc00 R08: 0000000000000000 R09: c00000010000028b R10: 0000000000055198 R11: ffffb3b6c001ea58 R12: ffff91db80e05010 R13: 000000000000000a R14: 0000000000000006 R15: 0000000000000040 FS: 0000000000000000(0000) GS:ffff91db1f840000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffff8f220860 CR3: 00000001f9580004 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> _raw_spin_lock_irqsave+0x30/0x40 mlx5_ib_poll_cq+0x4c/0xc50 [mlx5_ib] smc_wr_rx_tasklet_fn+0x56/0xa0 [smc] tasklet_action_common.isra.21+0x66/0x100 __do_softirq+0xd5/0x29c asm_call_irq_on_stack+0x12/0x20 </IRQ> do_softirq_own_stack+0x37/0x40 irq_exit_rcu+0x9d/0xa0 sysvec_call_function_single+0x34/0x80 asm_sysvec_call_function_single+0x12/0x20 Fixes: bd4ad57718cc ("smc: initialize IB transport incl. PD, MR, QP, CQ, event, WR") Signed-off-by: Yacan Liu <liuyacan@corp.netease.com> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-18net/smc: Allow virtually contiguous sndbufs or RMBs for SMC-RWen Gu
On long-running enterprise production servers, high-order contiguous memory pages are usually very rare and in most cases we can only get fragmented pages. When replacing TCP with SMC-R in such production scenarios, attempting to allocate high-order physically contiguous sndbufs and RMBs may result in frequent memory compaction, which will cause unexpected hung issue and further stability risks. So this patch is aimed to allow SMC-R link group to use virtually contiguous sndbufs and RMBs to avoid potential issues mentioned above. Whether to use physically or virtually contiguous buffers can be set by sysctl smcr_buf_type. Note that using virtually contiguous buffers will bring an acceptable performance regression, which can be mainly divided into two parts: 1) regression in data path, which is brought by additional address translation of sndbuf by RNIC in Tx. But in general, translating address through MTT is fast. Taking 256KB sndbuf and RMB as an example, the comparisons in qperf latency and bandwidth test with physically and virtually contiguous buffers are as follows: - client: smc_run taskset -c <cpu> qperf <server> -oo msg_size:1:64K:*2\ -t 5 -vu tcp_{bw|lat} - server: smc_run taskset -c <cpu> qperf [latency] msgsize tcp smcr smcr-use-virt-buf 1 11.17 us 7.56 us 7.51 us (-0.67%) 2 10.65 us 7.74 us 7.56 us (-2.31%) 4 11.11 us 7.52 us 7.59 us ( 0.84%) 8 10.83 us 7.55 us 7.51 us (-0.48%) 16 11.21 us 7.46 us 7.51 us ( 0.71%) 32 10.65 us 7.53 us 7.58 us ( 0.61%) 64 10.95 us 7.74 us 7.80 us ( 0.76%) 128 11.14 us 7.83 us 7.87 us ( 0.47%) 256 10.97 us 7.94 us 7.92 us (-0.28%) 512 11.23 us 7.94 us 8.20 us ( 3.25%) 1024 11.60 us 8.12 us 8.20 us ( 0.96%) 2048 14.04 us 8.30 us 8.51 us ( 2.49%) 4096 16.88 us 9.13 us 9.07 us (-0.64%) 8192 22.50 us 10.56 us 11.22 us ( 6.26%) 16384 28.99 us 12.88 us 13.83 us ( 7.37%) 32768 40.13 us 16.76 us 16.95 us ( 1.16%) 65536 68.70 us 24.68 us 24.85 us ( 0.68%) [bandwidth] msgsize tcp smcr smcr-use-virt-buf 1 1.65 MB/s 1.59 MB/s 1.53 MB/s (-3.88%) 2 3.32 MB/s 3.17 MB/s 3.08 MB/s (-2.67%) 4 6.66 MB/s 6.33 MB/s 6.09 MB/s (-3.85%) 8 13.67 MB/s 13.45 MB/s 11.97 MB/s (-10.99%) 16 25.36 MB/s 27.15 MB/s 24.16 MB/s (-11.01%) 32 48.22 MB/s 54.24 MB/s 49.41 MB/s (-8.89%) 64 106.79 MB/s 107.32 MB/s 99.05 MB/s (-7.71%) 128 210.21 MB/s 202.46 MB/s 201.02 MB/s (-0.71%) 256 400.81 MB/s 416.81 MB/s 393.52 MB/s (-5.59%) 512 746.49 MB/s 834.12 MB/s 809.99 MB/s (-2.89%) 1024 1292.33 MB/s 1641.96 MB/s 1571.82 MB/s (-4.27%) 2048 2007.64 MB/s 2760.44 MB/s 2717.68 MB/s (-1.55%) 4096 2665.17 MB/s 4157.44 MB/s 4070.76 MB/s (-2.09%) 8192 3159.72 MB/s 4361.57 MB/s 4270.65 MB/s (-2.08%) 16384 4186.70 MB/s 4574.13 MB/s 4501.17 MB/s (-1.60%) 32768 4093.21 MB/s 4487.42 MB/s 4322.43 MB/s (-3.68%) 65536 4057.14 MB/s 4735.61 MB/s 4555.17 MB/s (-3.81%) 2) regression in buffer initialization and destruction path, which is brought by additional MR operations of sndbufs. But thanks to link group buffer reuse mechanism, the impact of this kind of regression decreases as times of buffer reuse increases. Taking 256KB sndbuf and RMB as an example, latency of some key SMC-R buffer-related function obtained by bpftrace are as follows: Function Phys-bufs Virt-bufs smcr_new_buf_create() 67154 ns 79164 ns smc_ib_buf_map_sg() 525 ns 928 ns smc_ib_get_memory_region() 162294 ns 161191 ns smc_wr_reg_send() 9957 ns 9635 ns smc_ib_put_memory_region() 203548 ns 198374 ns smc_ib_buf_unmap_sg() 508 ns 1158 ns ------------ Test environment notes: 1. Above tests run on 2 VMs within the same Host. 2. The NIC is ConnectX-4Lx, using SRIOV and passing through 2 VFs to the each VM respectively. 3. VMs' vCPUs are binded to different physical CPUs, and the binded physical CPUs are isolated by `isolcpus=xxx` cmdline. 4. NICs' queue number are set to 1. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-18net/smc: Use sysctl-specified types of buffers in new link groupWen Gu
This patch introduces a new SMC-R specific element buf_type in struct smc_link_group, for recording the value of sysctl smcr_buf_type when link group is created. New created link group will create and reuse buffers of the type specified by buf_type. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-18net/smc: Introduce a sysctl for setting SMC-R buffer typeWen Gu
This patch introduces the sysctl smcr_buf_type for setting the type of SMC-R sndbufs and RMBs. Valid values includes: - SMCR_PHYS_CONT_BUFS, which means use physically contiguous buffers for better performance and is the default value. - SMCR_VIRT_CONT_BUFS, which means use virtually contiguous buffers in case of physically contiguous memory is scarce. - SMCR_MIXED_BUFS, which means first try to use physically contiguous buffers. If not available, then use virtually contiguous buffers. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-18net/smc: optimize for smc_sndbuf_sync_sg_for_device and smc_rmb_sync_sg_for_cpuGuangguan Wang
Some CPU, such as Xeon, can guarantee DMA cache coherency. So it is no need to use dma sync APIs to flush cache on such CPUs. In order to avoid calling dma sync APIs on the IO path, use the dma_need_sync to check whether smc_buf_desc needs dma sync when creating smc_buf_desc. Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-18net/smc: remove redundant dma sync opsGuangguan Wang
smc_ib_sync_sg_for_cpu/device are the ops used for dma memory cache consistency. Smc sndbufs are dma buffers, where CPU writes data to it and PCIE device reads data from it. So for sndbufs, smc_ib_sync_sg_for_device is needed and smc_ib_sync_sg_for_cpu is redundant as PCIE device will not write the buffers. Smc rmbs are dma buffers, where PCIE device write data to it and CPU read data from it. So for rmbs, smc_ib_sync_sg_for_cpu is needed and smc_ib_sync_sg_for_device is redundant as CPU will not write the buffers. Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-13net/smc: Resolve the race between SMC-R link access and clearWen Gu
We encountered some crashes caused by the race between SMC-R link access and link clear that triggered by abnormal link group termination, such as port error. Here is an example of this kind of crashes: BUG: kernel NULL pointer dereference, address: 0000000000000000 Workqueue: smc_hs_wq smc_listen_work [smc] RIP: 0010:smc_llc_flow_initiate+0x44/0x190 [smc] Call Trace: <TASK> ? __smc_buf_create+0x75a/0x950 [smc] smcr_lgr_reg_rmbs+0x2a/0xbf [smc] smc_listen_work+0xf72/0x1230 [smc] ? process_one_work+0x25c/0x600 process_one_work+0x25c/0x600 worker_thread+0x4f/0x3a0 ? process_one_work+0x600/0x600 kthread+0x15d/0x1a0 ? set_kthread_struct+0x40/0x40 ret_from_fork+0x1f/0x30 </TASK> smc_listen_work() __smc_lgr_terminate() --------------------------------------------------------------- | smc_lgr_free() | |- smcr_link_clear() | |- memset(lnk, 0) smc_listen_rdma_reg() | |- smcr_lgr_reg_rmbs() | |- smc_llc_flow_initiate() | |- access lnk->lgr (panic) | These crashes are similarly caused by clearing SMC-R link resources when some functions is still accessing to them. This patch tries to fix the issue by introducing reference count of SMC-R links and ensuring that the sensitive resources of links won't be cleared until reference count reaches zero. The operation to the SMC-R link reference count can be concluded as follows: object [hold or initialized as 1] [put] -------------------------------------------------------------------- links smcr_link_init() smcr_link_clear() connections smc_conn_create() smc_conn_free() Through this way, the clear of SMC-R links is later than the free of all the smc connections above it, thus avoiding the unsafe reference to SMC-R links. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-13net/smc: Introduce a new conn->lgr validity check helperWen Gu
It is no longer suitable to identify whether a smc connection is registered in a link group through checking if conn->lgr is NULL, because conn->lgr won't be reset even the connection is unregistered from a link group. So this patch introduces a new helper smc_conn_lgr_valid() and replaces all the check of conn->lgr in original implementation with the new helper to judge if conn->lgr is valid to use. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-13net/smc: Resolve the race between link group access and terminationWen Gu
We encountered some crashes caused by the race between the access and the termination of link groups. Here are some of panic stacks we met: 1) Race between smc_clc_wait_msg() and __smc_lgr_terminate() BUG: kernel NULL pointer dereference, address: 00000000000002f0 Workqueue: smc_hs_wq smc_listen_work [smc] RIP: 0010:smc_clc_wait_msg+0x3eb/0x5c0 [smc] Call Trace: <TASK> ? smc_clc_send_accept+0x45/0xa0 [smc] ? smc_clc_send_accept+0x45/0xa0 [smc] smc_listen_work+0x783/0x1220 [smc] ? finish_task_switch+0xc4/0x2e0 ? process_one_work+0x1ad/0x3c0 process_one_work+0x1ad/0x3c0 worker_thread+0x4c/0x390 ? rescuer_thread+0x320/0x320 kthread+0x149/0x190 ? set_kthread_struct+0x40/0x40 ret_from_fork+0x1f/0x30 </TASK> smc_listen_work() abnormal case like port error --------------------------------------------------------------- | __smc_lgr_terminate() | |- smc_conn_kill() | |- smc_lgr_unregister_conn() | |- set conn->lgr = NULL smc_clc_wait_msg() | |- access conn->lgr (panic) | 2) Race between smc_setsockopt() and __smc_lgr_terminate() BUG: kernel NULL pointer dereference, address: 00000000000002e8 RIP: 0010:smc_setsockopt+0x17a/0x280 [smc] Call Trace: <TASK> __sys_setsockopt+0xfc/0x190 __x64_sys_setsockopt+0x20/0x30 do_syscall_64+0x34/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae </TASK> smc_setsockopt() abnormal case like port error -------------------------------------------------------------- | __smc_lgr_terminate() | |- smc_conn_kill() | |- smc_lgr_unregister_conn() | |- set conn->lgr = NULL mod_delayed_work() | |- access conn->lgr (panic) | There are some other panic places and they are caused by the similar reason as described above, which is accessing link group after termination, thus getting a NULL pointer or invalid resource. Currently, there seems to be no synchronization between the link group access and a sudden termination of it. This patch tries to fix this by introducing reference count of link group and not freeing link group until reference count is zero. Link group might be referred to by links or smc connections. So the operation to the link group reference count can be concluded as follows: object [hold or initialized as 1] [put] ------------------------------------------------------------------- link group smc_lgr_create() smc_lgr_free() connections smc_conn_create() smc_conn_free() links smcr_link_init() smcr_link_clear() Througth this way, we extend the life cycle of link group and ensure it is longer than the life cycle of connections and links above it, so that avoid invalid access to link group after its termination. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Merge in fixes directly in prep for the 5.17 merge window. No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-06net/smc: Reset conn->lgr when link group registration failsWen Gu
SMC connections might fail to be registered in a link group due to unable to find a usable link during its creation. As a result, smc_conn_create() will return a failure and most resources related to the connection won't be applied or initialized, such as conn->abort_work or conn->lnk. If smc_conn_free() is invoked later, it will try to access the uninitialized resources related to the connection, thus causing a warning or crash. This patch tries to fix this by resetting conn->lgr to NULL if an abnormal exit occurs in smc_lgr_register_conn(), thus avoiding the access to uninitialized resources in smc_conn_free(). Meanwhile, the new created link group should be terminated if smc connections can't be registered in it. So smc_lgr_cleanup_early() is modified to take care of link group only and invoked to terminate unusable link group by smc_conn_create(). The call to smc_conn_free() is moved out from smc_lgr_cleanup_early() to smc_conn_abort(). Fixes: 56bc3b2094b4 ("net/smc: assign link to a new connection") Suggested-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Wen Gu <guwen@linux.alibaba.com> Acked-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-02net/smc: add comments for smc_link_{usable|sendable}Dust Li
Add comments for both smc_link_sendable() and smc_link_usable() to help better distinguish and use them. No function changes. Signed-off-by: Dust Li <dust.li@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-02net/smc: Introduce net namespace support for linkgroupTony Lu
Currently, rdma device supports exclusive net namespace isolation, however linkgroup doesn't know and support ibdev net namespace. Applications in the containers don't want to share the nics if we enabled rdma exclusive mode. Every net namespaces should have their own linkgroups. This patch introduce a new field net for linkgroup, which is standing for the ibdev net namespace in the linkgroup. The net in linkgroup is initialized with the net namespace of link's ibdev. It compares the net of linkgroup and sock or ibdev before choose it, if no matched, create new one in current net namespace. If rdma net namespace exclusive mode is not enabled, it behaves as before. Signed-off-by: Tony Lu <tonylu@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-28net/smc: don't send CDC/LLC message if link not readyDust Li
We found smc_llc_send_link_delete_all() sometimes wait for 2s timeout when testing with RDMA link up/down. It is possible when a smc_link is in ACTIVATING state, the underlaying QP is still in RESET or RTR state, which cannot send any messages out. smc_llc_send_link_delete_all() use smc_link_usable() to checks whether the link is usable, if the QP is still in RESET or RTR state, but the smc_link is in ACTIVATING, this LLC message will always fail without any CQE entering the CQ, and we will always wait 2s before timeout. Since we cannot send any messages through the QP before the QP enter RTS. I add a wrapper smc_link_sendable() which checks the state of QP along with the link state. And replace smc_link_usable() with smc_link_sendable() in all LLC & CDC message sending routine. Fixes: 5f08318f617b ("smc: connection data control (CDC)") Signed-off-by: Dust Li <dust.li@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16net/smc: extend LLC layer for SMC-Rv2Karsten Graul
Add support for large v2 LLC control messages in smc_llc.c. The new large work request buffer allows to combine control messages into one packet that had to be spread over several packets before. Add handling of the new v2 LLC messages. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16net/smc: add v2 support to the work request layerKarsten Graul
In the work request layer define one large v2 buffer for each link group that is used to transmit and receive large LLC control messages. Add the completion queue handling for this buffer. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16net/smc: add listen processing for SMC-Rv2Karsten Graul
Implement the server side of the SMC-Rv2 processing. Process incoming CLC messages, find eligible devices and check for a valid route to the remote peer. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16net/smc: add SMC-Rv2 connection establishmentKarsten Graul
Send a CLC proposal message, and the remote side process this type of message and determine the target GID. Check for a valid route to this GID, and complete the connection establishment. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16net/smc: prepare for SMC-Rv2 connectionKarsten Graul
Prepare the connection establishment with SMC-Rv2. Detect eligible RoCE cards and indicate all supported SMC modes for the connection. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-14net/smc: add support for user defined EIDsKarsten Graul
SMC-Dv2 allows users to define EIDs which allows to create separate name spaces enabling users to cluster their SMC-Dv2 connections. Add support for user defined EIDs and extent the generic netlink interface so users can add, remove and dump EIDs. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Reviewed-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-09net/smc: Correct smc link connection counter in case of smc clientGuvenc Gulce
SMC clients may be assigned to a different link after the initial connection between two peers was established. In such a case, the connection counter was not correctly set. Update the connection counter correctly when a smc client connection is assigned to a different smc link. Fixes: 07d51580ff65 ("net/smc: Add connection counters for links") Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Tested-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-09net/smc: fix wait on already cleared linkKarsten Graul
There can be a race between the waiters for a tx work request buffer and the link down processing that finally clears the link. Although all waiters are woken up before the link is cleared there might be waiters which did not yet get back control and are still waiting. This results in an access to a cleared wait queue head. Fix this by introducing atomic reference counting around the wait calls, and wait with the link clear processing until all waiters have finished. Move the work request layer related calls into smc_wr.c and set the link state to INACTIVE before calling smcr_link_clear() in smc_llc_srv_add_link(). Fixes: 15e1b99aadfb ("net/smc: no WR buffer wait for terminating link group") Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-01net: smc: Remove repeated struct declarationWan Jiabing
struct smc_clc_msg_local is declared twice. One is declared at 301st line. The blew one is not needed. Remove the duplicate. Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Acked-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-12-01net/smc: Add support for obtaining SMCD device listGuvenc Gulce
Deliver SMCD device information via netlink based diagnostic interface. Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-01net/smc: Add SMC-D Linkgroup diagnostic supportGuvenc Gulce
Deliver SMCD Linkgroup information via netlink based diagnostic interface. Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-01net/smc: Introduce SMCR get link commandGuvenc Gulce
Introduce get link command which loops through all available links of all available link groups. It uses the SMC-R linkgroup list as entry point, not the socket list, which makes linkgroup diagnosis possible, in case linkgroup does not contain active connections anymore. Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-01net/smc: Introduce SMCR get linkgroup commandGuvenc Gulce
Introduce get linkgroup command which loops through all available SMCR linkgroups. It uses the SMC-R linkgroup list as entry point, not the socket list, which makes linkgroup diagnosis possible, in case linkgroup does not contain active connections anymore. Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-01net/smc: Add support for obtaining system informationGuvenc Gulce
Add new netlink command to obtain system information of the smc module. Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-01net/smc: Add diagnostic information to link structureGuvenc Gulce
During link creation add net-device ifindex and ib-device name to link structure. This is needed for diagnostic purposes. When diagnostic information is gathered, we need to traverse device, linkgroup and link structures, to be able to do that we need to hold a spinlock for the linkgroup list, without this diagnostic information in link structure, another device list mutex holding would be necessary to dereference the device pointer in the link structure which would be impossible when holding a spinlock already. Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-01net/smc: Add connection counters for linksGuvenc Gulce
Add connection counters to the structure of the link. Increase/decrease the counters as needed in the corresponding routines. Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-31net/smc: improve return codes for SMC-Dv2Karsten Graul
To allow better problem diagnosis the return codes for SMC-Dv2 are improved by this patch. A few more CLC DECLINE codes are defined and sent to the peer when an SMC connection cannot be established. There are now multiple SMC variations that are offered by the client and the server may encounter problems to initialize all of them. Because only one diagnosis code can be sent to the client the decision was made to send the first code that was encountered. Because the server tries the variations in the order of importance (SMC-Dv2, SMC-D, SMC-R) this makes sure that the diagnosis code of the most important variation is sent. v2: initialize rc in smc_listen_v2_check(). Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Link: https://lore.kernel.org/r/20201031181938.69903-1-kgraul@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-28net/smc: introduce CLC first contact extensionUrsula Braun
SMC Version 2 defines a first contact extension for CLC accept and CLC confirm. This patch covers sending and receiving of the CLC first contact extension. Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28net/smc: determine accepted ISM devicesUrsula Braun
SMCD Version 2 allows to propose up to 8 additional ISM devices offered to the peer as candidates for SMCD communication. This patch covers the server side, i.e. selection of an ISM device matching one of the proposed ISM devices, that will be used for CLC accept Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28net/smc: determine proposed ISM devicesUrsula Braun
SMCD Version 2 allows to propose up to 8 additional ISM devices offered to the peer as candidates for SMCD communication. This patch covers determination of the ISM devices to be proposed. ISM devices without PNETID are preferred, since ISM devices with PNETID are a V1 leftover and will disappear over the time. Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28net/smc: introduce CHID callback for ISM devicesUrsula Braun
With SMCD version 2 the CHIDs of ISM devices are needed for the CLC handshake. This patch provides the new callback to retrieve the CHID of an ISM device. Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28net/smc: prepare for more proposed ISM devicesUrsula Braun
SMCD Version 2 allows proposing of up to 8 ISM devices in addition to the native ISM device of SMCD Version 1. This patch prepares the struct smc_init_info to deal with these additional 8 ISM devices. Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-10net/smc: use separate work queues for different worker typesKarsten Graul
There are 6 types of workers which exist per smc connection. 3 of them are used for listen and handshake processing, another 2 are used for close and abort processing and 1 is the tx worker that moves calls to sleeping functions into a worker. To prevent flooding of the system work queue when many connections are opened or closed at the same time (some pattern uperf implements), move those workers to one of 3 smc-specific work queues. Two work queues are module-global and used for handshake and close workers. The third work queue is defined per link group and used by the tx workers that may sleep waiting for resources of this link group. And in smc_llc_enqueue() queue the llc_event_work work to the system prio work queue because its critical that this work is started fast. Reviewed-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-10net/smc: immediate freeing in smc_lgr_cleanup_early()Ursula Braun
smc_lgr_cleanup_early() schedules the free worker with delay. DMB unregistering occurs in this delayed worker increasing the risk to reach the SMCD SBA limit without need. Terminate the linkgroup immediately, since termination means early DMB unregistering. For SMCD the global smc_server_lgr_pending lock is given up early. A linkgroup to be given up with smc_lgr_cleanup_early() may already contain more than one connection. Using __smc_lgr_terminate() in smc_lgr_cleanup_early() covers this. And consolidate smc_ism_put_vlan() and smc_put_device() into smc_lgr_free() only. Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-10net/smc: introduce better field namesUrsula Braun
Field names "srv_first_contact" and "cln_first_contact" are misleading, since they apply to both, server and client. Rename them to "first_contact_peer" and "first_contact_local". Rename "ism_gid" by the more precise name "ism_peer_gid". Rename version constant "SMC_CLC_V1" into "SMC_V1". No functional change. Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19net/smc: do not call dma sync for unmapped memoryKarsten Graul
The dma related ...sync_sg... functions check the link state before the dma function is actually called. But the check in smc_link_usable() allows links in ACTIVATING state which are not yet mapped to dma memory. Under high load it may happen that the sync_sg functions are called for such a link which results in an debug output like DMA-API: mlx5_core 0002:00:00.0: device driver tries to sync DMA memory it has not allocated [device address=0x0000000103370000] [size=65536 bytes] To fix that introduce a helper to check for the link state ACTIVE and use it where appropriate. And move the link state update to ACTIVATING to the end of smcr_link_init() when most initial setup is done. Reviewed-by: Ursula Braun <ubraun@linux.ibm.com> Fixes: d854fcbfaeda ("net/smc: add new link state and related helpers") Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>