- Nov 29, 2016
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Chuck Lever authored
When the inline threshold size is set to large values (say, 32KB) any NFSv4.1 CB request from the server gets a reply with status NFS4ERR_RESOURCE. Looks like there are some upper layer assumptions about the maximum size of a reply (for example, in process_op). Cap the size of the NFSv4 client's reply resources at a page. Signed-off-by:
Chuck Lever <chuck.lever@oracle.com> Signed-off-by:
Anna Schumaker <Anna.Schumaker@Netapp.com>
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- Nov 14, 2016
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Scott Mayhew authored
This fixes the following panic that can occur with NFSoRDMA. general protection fault: 0000 [#1] SMP Modules linked in: rpcrdma ib_isert iscsi_target_mod ib_iser libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp scsi_tgt ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm mlx5_ib ib_core intel_powerclamp coretemp kvm_intel kvm sg ioatdma ipmi_devintf ipmi_ssif dcdbas iTCO_wdt iTCO_vendor_support pcspkr irqbypass sb_edac shpchp dca crc32_pclmul ghash_clmulni_intel edac_core lpc_ich aesni_intel lrw gf128mul glue_helper ablk_helper mei_me mei ipmi_si cryptd wmi ipmi_msghandler acpi_pad acpi_power_meter nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod crc_t10dif crct10dif_generic mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt ahci fb_sys_fops ttm libahci mlx5_core tg3 crct10dif_pclmul drm crct10dif_common ptp i2c_core libata crc32c_intel pps_core fjes dm_mirror dm_region_hash dm_log dm_mod CPU: 1 PID: 120 Comm: kworker/1:1 Not tainted 3.10.0-514.el7.x86_64 #1 Hardware name: Dell Inc. PowerEdge R320/0KM5PX, BIOS 2.4.2 01/29/2015 Workqueue: events check_lifetime task: ffff88031f506dd0 ti: ffff88031f584000 task.ti: ffff88031f584000 RIP: 0010:[<ffffffff8168d847>] [<ffffffff8168d847>] _raw_spin_lock_bh+0x17/0x50 RSP: 0018:ffff88031f587ba8 EFLAGS: 00010206 RAX: 0000000000020000 RBX: 20041fac02080072 RCX: ffff88031f587fd8 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 20041fac02080072 RBP: ffff88031f587bb0 R08: 0000000000000008 R09: ffffffff8155be77 R10: ffff880322a59b00 R11: ffffea000bf39f00 R12: 20041fac02080072 R13: 000000000000000d R14: ffff8800c4fbd800 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff880322a40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3c52d4547e CR3: 00000000019ba000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: 20041fac02080002 ffff88031f587bd0 ffffffff81557830 20041fac02080002 ffff88031f587c78 ffff88031f587c40 ffffffff8155ae08 000000010157df32 0000000800000001 ffff88031f587c20 ffffffff81096acb ffffffff81aa37d0 Call Trace: [<ffffffff81557830>] lock_sock_nested+0x20/0x50 [<ffffffff8155ae08>] sock_setsockopt+0x78/0x940 [<ffffffff81096acb>] ? lock_timer_base.isra.33+0x2b/0x50 [<ffffffff8155397d>] kernel_setsockopt+0x4d/0x50 [<ffffffffa0386284>] svc_age_temp_xprts_now+0x174/0x1e0 [sunrpc] [<ffffffffa03b681d>] nfsd_inetaddr_event+0x9d/0xd0 [nfsd] [<ffffffff81691ebc>] notifier_call_chain+0x4c/0x70 [<ffffffff810b687d>] __blocking_notifier_call_chain+0x4d/0x70 [<ffffffff810b68b6>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff815e8538>] __inet_del_ifa+0x168/0x2d0 [<ffffffff815e8cef>] check_lifetime+0x25f/0x270 [<ffffffff810a7f3b>] process_one_work+0x17b/0x470 [<ffffffff810a8d76>] worker_thread+0x126/0x410 [<ffffffff810a8c50>] ? rescuer_thread+0x460/0x460 [<ffffffff810b052f>] kthread+0xcf/0xe0 [<ffffffff810b0460>] ? kthread_create_on_node+0x140/0x140 [<ffffffff81696418>] ret_from_fork+0x58/0x90 [<ffffffff810b0460>] ? kthread_create_on_node+0x140/0x140 Code: ca 75 f1 5d c3 0f 1f 80 00 00 00 00 eb d9 66 0f 1f 44 00 00 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb e8 7e 04 a0 ff b8 00 00 02 00 <f0> 0f c1 03 89 c2 c1 ea 10 66 39 c2 75 03 5b 5d c3 83 e2 fe 0f RIP [<ffffffff8168d847>] _raw_spin_lock_bh+0x17/0x50 RSP <ffff88031f587ba8> Signed-off-by:
Scott Mayhew <smayhew@redhat.com> Fixes: c3d4879e ("sunrpc: Add a function to close temporary transports immediately") Reviewed-by:
J. Bruce Fields <bfields@redhat.com>
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- Nov 10, 2016
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Chuck Lever authored
When a LOCALINV WR is flushed, the frmr is marked STALE, then frwr_op_unmap_sync DMA-unmaps the frmr's SGL. These STALE frmrs are then recovered when frwr_op_map hunts for an INVALID frmr to use. All other cases that need frmr recovery leave that SGL DMA-mapped. The FRMR recovery path unconditionally DMA-unmaps the frmr's SGL. To avoid DMA unmapping the SGL twice for flushed LOCAL_INV WRs, alter the recovery logic (rather than the hot frwr_op_unmap_sync path) to distinguish among these cases. This solution also takes care of the case where multiple LOCAL_INV WRs are issued for the same rpcrdma_req, some complete successfully, but some are flushed. Reported-by:
Vasco Steinmetz <linux@kyberraum.net> Signed-off-by:
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- Nov 07, 2016
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Anna Schumaker authored
We need to hold the rcu_read_lock() when calling rcu_dereference(), otherwise we can't guarantee that the object being dereferenced still exists. Fixes: 39e5d2df ("SUNRPC search xprt switch for sockaddr") Signed-off-by:
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- Nov 01, 2016
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Chuck Lever authored
The underlying transport releases the page pointed to by rq_buffer during xprt_rdma_bc_send_request. When the backchannel reply arrives, rq_rbuffer then points to freed memory. Fixes: 68778945 ('SUNRPC: Separate buffer pointers for RPC ...') Signed-off-by:
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- Oct 28, 2016
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Jeff Layton authored
We've been seeing some crashes in testing that look like this: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8135ce99>] memcpy_orig+0x29/0x110 PGD 212ca2067 PUD 212ca3067 PMD 0 Oops: 0002 [#1] SMP Modules linked in: rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache ppdev parport_pc i2c_piix4 sg parport i2c_core virtio_balloon pcspkr acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod ata_generic pata_acpi virtio_scsi 8139too ata_piix libata 8139cp mii virtio_pci floppy virtio_ring serio_raw virtio CPU: 1 PID: 1540 Comm: nfsd Not tainted 4.9.0-rc1 #39 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2007 task: ffff88020d7ed200 task.stack: ffff880211838000 RIP: 0010:[<ffffffff8135ce99>] [<ffffffff8135ce99>] memcpy_orig+0x29/0x110 RSP: 0018:ffff88021183bdd0 EFLAGS: 00010206 RAX: 0000000000000000 RBX: ffff88020d7fa000 RCX: 000000f400000000 RDX: 0000000000000014 RSI: ffff880212927020 RDI: 0000000000000000 RBP: ffff88021183be30 R08: 01000000ef896996 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff880211704ca8 R13: ffff88021473f000 R14: 00000000ef896996 R15: ffff880211704800 FS: 0000000000000000(0000) GS:ffff88021fc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000212ca1000 CR4: 00000000000006e0 Stack: ffffffffa01ea087 ffffffff63400001 ffff880215145e00 ffff880211bacd00 ffff88021473f2b8 0000000000000004 00000000d0679d67 ffff880211bacd00 ffff88020d7fa000 ffff88021473f000 0000000000000000 ffff88020d7faa30 Call Trace: [<ffffffffa01ea087>] ? svc_tcp_recvfrom+0x5a7/0x790 [sunrpc] [<ffffffffa01f84d8>] svc_recv+0xad8/0xbd0 [sunrpc] [<ffffffffa0262d5e>] nfsd+0xde/0x160 [nfsd] [<ffffffffa0262c80>] ? nfsd_destroy+0x60/0x60 [nfsd] [<ffffffff810a9418>] kthread+0xd8/0xf0 [<ffffffff816dbdbf>] ret_from_fork+0x1f/0x40 [<ffffffff810a9340>] ? kthread_park+0x60/0x60 Code: 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe 7c 35 48 83 ea 20 48 83 ea 20 4c 8b 06 4c 8b 4e 08 4c 8b 56 10 4c 8b 5e 18 48 8d 76 20 <4c> 89 07 4c 89 4f 08 4c 89 57 10 4c 89 5f 18 48 8d 7f 20 73 d4 RIP [<ffffffff8135ce99>] memcpy_orig+0x29/0x110 RSP <ffff88021183bdd0> CR2: 0000000000000000 Both Bruce and Eryu ran a bisect here and found that the problematic patch was 68778945 (SUNRPC: Separate buffer pointers for RPC Call and Reply messages). That patch changed rpc_xdr_encode to use a new rq_rbuffer pointer to set up the receive buffer, but didn't change all of the necessary codepaths to set it properly. In particular the backchannel setup was missing. We need to set rq_rbuffer whenever rq_buffer is set. Ensure that it is. Reviewed-by:
Eryu Guan <guaneryu@gmail.com> Tested-by:
J. Bruce Fields <bfields@fieldses.org> Signed-off-by:
Jeff Layton <jlayton@redhat.com> Signed-off-by:
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- Oct 26, 2016
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J. Bruce Fields authored
As of ac4e97ab "scatterlist: sg_set_buf() argument must be in linear mapping", sg_set_buf hits a BUG when make_checksum_v2->xdr_process_buf, among other callers, passes it memory on the stack. We only need a scatterlist to pass this to the crypto code, and it seems like overkill to require kmalloc'd memory just to encrypt a few bytes, but for now this seems the best fix. Many of these callers are in the NFS write paths, so we allocate with GFP_NOFS. It might be possible to do without allocations here entirely, but that would probably be a bigger project. Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by:
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- Oct 08, 2016
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Alexey Dobriyan authored
Current supplementary groups code can massively overallocate memory and is implemented in a way so that access to individual gid is done via 2D array. If number of gids is <= 32, memory allocation is more or less tolerable (140/148 bytes). But if it is not, code allocates full page (!) regardless and, what's even more fun, doesn't reuse small 32-entry array. 2D array means dependent shifts, loads and LEAs without possibility to optimize them (gid is never known at compile time). All of the above is unnecessary. Switch to the usual trailing-zero-len-array scheme. Memory is allocated with kmalloc/vmalloc() and only as much as needed. Accesses become simpler (LEA 8(gi,idx,4) or even without displacement). Maximum number of gids is 65536 which translates to 256KB+8 bytes. I think kernel can handle such allocation. On my usual desktop system with whole 9 (nine) aux groups, struct group_info shrinks from 148 bytes to 44 bytes, yay! Nice side effects: - "gi->gid[i]" is shorter than "GROUP_AT(gi, i)", less typing, - fix little mess in net/ipv4/ping.c should have been using GROUP_AT macro but this point becomes moot, - aux group allocation is persistent and should be accounted as such. Link: http://lkml.kernel.org/r/20160817201927.GA2096@p183.telecom.by Signed-off-by:
Alexey Dobriyan <adobriyan@gmail.com> Cc: Vasily Kulikov <segoon@openwall.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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- Sep 30, 2016
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Frank Sorenson authored
Replace the generic code to hash the auth_cred with the call to the auth-specific hash function in the rpc_authops struct. Signed-off-by:
Frank Sorenson <sorenson@redhat.com> Signed-off-by:
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Frank Sorenson authored
Add a hash_cred() function for RPCSEC_GSS, using only the uid from the auth_cred. Signed-off-by:
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Frank Sorenson authored
Add a hash_cred() function for auth_unix, using both the uid and gid from the auth_cred. Signed-off-by:
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Frank Sorenson authored
Add a hash_cred() function for generic_auth, using both the uid and gid from the auth_cred. Signed-off-by:
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- Sep 28, 2016
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Deepa Dinamani authored
CURRENT_TIME macro is not appropriate for filesystems as it doesn't use the right granularity for filesystem timestamps. Use current_time() instead. CURRENT_TIME is also not y2038 safe. This is also in preparation for the patch that transitions vfs timestamps to use 64 bit time and hence make them y2038 safe. As part of the effort current_time() will be extended to do range checks. Hence, it is necessary for all file system timestamps to use current_time(). Also, current_time() will be transitioned along with vfs to be y2038 safe. Note that whenever a single call to current_time() is used to change timestamps in different inodes, it is because they share the same time granularity. Signed-off-by:
Deepa Dinamani <deepa.kernel@gmail.com> Reviewed-by:
Arnd Bergmann <arnd@arndb.de> Acked-by:
Felipe Balbi <balbi@kernel.org> Acked-by:
Steven Whitehouse <swhiteho@redhat.com> Acked-by:
Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Acked-by:
David Sterba <dsterba@suse.com> Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk>
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- Sep 27, 2016
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Ke Wang authored
sunrpc uses workqueue to clean cache regulary. There is no real dependency of executing work on the cpu which queueing it. On a idle system, especially for a heterogeneous systems like big.LITTLE, it is observed that the big idle cpu was woke up many times just to service this work, which against the principle of power saving. It would be better if we can schedule it on a cpu which the scheduler believes to be the most appropriate one. After apply this patch, system_wq will be replaced by system_power_efficient_wq for sunrpc. This functionality is enabled when CONFIG_WQ_POWER_EFFICIENT is selected. Signed-off-by:
Ke Wang <ke.wang@spreadtrum.com> Signed-off-by:
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- Sep 23, 2016
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Christoph Hellwig authored
Instead of exposing ib_get_dma_mr to ULPs and letting them use it more or less unchecked, this moves the capability of creating a global rkey into the RDMA core, where it can be easily audited. It also prints a warning everytime this feature is used as well. Signed-off-by:
Christoph Hellwig <hch@lst.de> Reviewed-by:
Sagi Grimberg <sagi@grimberg.me> Reviewed-by:
Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Reviewed-by:
Steve Wise <swise@opengridcomputing.com> Signed-off-by:
Doug Ledford <dledford@redhat.com>
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Chuck Lever authored
Support Remote Invalidation. A private message is exchanged with the client upon RDMA transport connect that indicates whether Send With Invalidation may be used by the server to send RPC replies. The invalidate_rkey is arbitrarily chosen from among rkeys present in the RPC-over-RDMA header's chunk lists. Send With Invalidate improves performance only when clients can recognize, while processing an RPC reply, that an rkey has already been invalidated. That has been submitted as a separate change. In the future, the RPC-over-RDMA protocol might support Remote Invalidation properly. The protocol needs to enable signaling between peers to indicate when Remote Invalidation can be used for each individual RPC. Signed-off-by:
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Chuck Lever authored
Prepare to receive an RDMA-CM private message when handling a new connection attempt, and send a similar message as part of connection acceptance. Both sides can communicate their various implementation limits. Implementations that don't support this sideband protocol ignore it. Signed-off-by:
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Chuck Lever authored
Message from syslogd@klimt at Aug 18 17:00:37 ... kernel:page:ffffea0020639b00 count:0 mapcount:0 mapping: (null) index:0x0 Aug 18 17:00:37 klimt kernel: flags: 0x2fffff80000000() Aug 18 17:00:37 klimt kernel: page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) Aug 18 17:00:37 klimt kernel: kernel BUG at /home/cel/src/linux/linux-2.6/include/linux/mm.h:445! Aug 18 17:00:37 klimt kernel: RIP: 0010:[<ffffffffa05c21c1>] svc_rdma_sendto+0x641/0x820 [rpcrdma] send_reply() assigns its page argument as the first page of ctxt. On error, send_reply() already invokes svc_rdma_put_context(ctxt, 1); which does a put_page() on that very page. No need to do that again as svc_rdma_sendto exits. Fixes: 3e1eeb98 ("svcrdma: Close connection when a send error occurs") Signed-off-by:
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Chuck Lever authored
The ctxt's count field is overloaded to mean the number of pages in the ctxt->page array and the number of SGEs in the ctxt->sge array. Typically these two numbers are the same. However, when an inline RPC reply is constructed from an xdr_buf with a tail iovec, the head and tail often occupy the same page, but each are DMA mapped independently. In that case, ->count equals the number of pages, but it does not equal the number of SGEs. There's one more SGE, for the tail iovec. Hence there is one more DMA mapping than there are pages in the ctxt->page array. This isn't a real problem until the server's iommu is enabled. Then each RPC reply that has content in that iovec orphans a DMA mapping that consists of real resources. krb5i and krb5p always populate that tail iovec. After a couple million sent krb5i/p RPC replies, the NFS server starts behaving erratically. Reboot is needed to clear the problem. Fixes: 9d11b51c ("svcrdma: Fix send_reply() scatter/gather set-up") Signed-off-by:
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Daniel Wagner authored
There is only one waiter for the completion, therefore there is no need to use complete_all(). Let's make that clear by using complete() instead of complete_all(). The usage pattern of the completion is: waiter context waker context frwr_op_unmap_sync() reinit_completion() ib_post_send() wait_for_completion() frwr_wc_localinv_wake() complete() Signed-off-by:
Daniel Wagner <daniel.wagner@bmw-carit.de> Cc: Anna Schumaker <Anna.Schumaker@Netapp.com> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: linux-nfs@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by:
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- Sep 22, 2016
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Trond Myklebust authored
Use xdr->nwords to tell us how much buffer remains. Signed-off-by:
Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by:
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Trond Myklebust authored
When we copy the first part of the data, we need to ensure that value of xdr->nwords is updated as well. Do so by calling __xdr_inline_decode() Signed-off-by:
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- Sep 19, 2016
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David Vrabel authored
Write space becoming available may race with putting the task to sleep in xprt_wait_for_buffer_space(). The existing mechanism to avoid the race does not work. This (edited) partial trace illustrates the problem: [1] rpc_task_run_action: task:43546@5 ... action=call_transmit [2] xs_write_space <-xs_tcp_write_space [3] xprt_write_space <-xs_write_space [4] rpc_task_sleep: task:43546@5 ... [5] xs_write_space <-xs_tcp_write_space [1] Task 43546 runs but is out of write space. [2] Space becomes available, xs_write_space() clears the SOCKWQ_ASYNC_NOSPACE bit. [3] xprt_write_space() attemts to wake xprt->snd_task (== 43546), but this has not yet been queued and the wake up is lost. [4] xs_nospace() is called which calls xprt_wait_for_buffer_space() which queues task 43546. [5] The call to sk->sk_write_space() at the end of xs_nospace() (which is supposed to handle the above race) does not call xprt_write_space() as the SOCKWQ_ASYNC_NOSPACE bit is clear and thus the task is not woken. Fix the race by resetting the SOCKWQ_ASYNC_NOSPACE bit in xs_nospace() so the second call to sk->sk_write_space() calls xprt_write_space(). Suggested-by:Trond Myklebust <trondmy@primarydata.com> Signed-off-by:
David Vrabel <david.vrabel@citrix.com> cc: stable@vger.kernel.org # 4.4 Signed-off-by:
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Chuck Lever authored
Clean up: the extra layer of indirection doesn't add value. Signed-off-by:
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Chuck Lever authored
Clean up: When converting xprtrdma to use the new CQ API, I missed a spot. The naming convention elsewhere is: {svc_rdma,rpcrdma}_wc_{operation} Signed-off-by: -
Chuck Lever authored
Tie frwr debugging messages together by always reporting the address of the frwr. Signed-off-by:
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Chuck Lever authored
The Version One default inline threshold is still 1KB. But allow testing with thresholds up to 64KB. This maximum is somewhat arbitrary. There's no fundamental architectural limit I'm aware of, but it's good to keep the size of Receive buffers reasonable. Now that Send can use a s/g list, a Send buffer is only as large as each RPC requires. Receive buffers are always the size of the inline threshold, however. Signed-off-by:
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Chuck Lever authored
An RPC Call message that is sent inline but that has a data payload (ie, one or more items in rq_snd_buf's page list) must be "pulled up:" - call_allocate has to reserve enough RPC Call buffer space to accommodate the data payload - call_transmit has to memcopy the rq_snd_buf's page list and tail into its head iovec before it is sent As the inline threshold is increased beyond its current 1KB default, however, this means data payloads of more than a few KB are copied by the host CPU. For example, if the inline threshold is increased just to 4KB, then NFS WRITE requests up to 4KB would involve a memcpy of the NFS WRITE's payload data into the RPC Call buffer. This is an undesirable amount of participation by the host CPU. The inline threshold may be much larger than 4KB in the future, after negotiation with a peer server. Instead of copying the components of rq_snd_buf into its head iovec, construct a gather list of these components, and send them all in place. The same approach is already used in the Linux server's RPC-over-RDMA reply path. This mechanism also eliminates the need for rpcrdma_tail_pullup, which is used to manage the XDR pad and trailing inline content when a Read list is present. This requires that the pages in rq_snd_buf's page list be DMA-mapped during marshaling, and unmapped when a data-bearing RPC is completed. This is slightly less efficient for very small I/O payloads, but significantly more efficient as data payload size and inline threshold increase past a kilobyte. Signed-off-by:
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Chuck Lever authored
Have frwr's ro_unmap_sync recognize an invalidated rkey that appears as part of a Receive completion. Local invalidation can be skipped for that rkey. Use an out-of-band signaling mechanism to indicate to the server that the client is prepared to receive RDMA Send With Invalidate. Signed-off-by:
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Chuck Lever authored
Send an RDMA-CM private message on connect, and look for one during a connection-established event. Both sides can communicate their various implementation limits. Implementations that don't support this sideband protocol ignore it. Once the client knows the server's inline threshold maxima, it can adjust the use of Reply chunks, and eliminate most use of Position Zero Read chunks. Moderately-sized I/O can be done using a pure inline RDMA Send instead of RDMA operations that require memory registration. Signed-off-by:
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Chuck Lever authored
Clean up: The fields in the recv_wr do not vary. There is no need to initialize them before each ib_post_recv(). This removes a large-ish data structure from the stack. Signed-off-by:
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Chuck Lever authored
Clean up: Most of the fields in each send_wr do not vary. There is no need to initialize them before each ib_post_send(). This removes a large-ish data structure from the stack. Signed-off-by:
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Chuck Lever authored
Clean up. Since commit fc664485 ("xprtrdma: Split the completion queue"), rpcrdma_ep_post_recv() no longer uses the "ep" argument. Signed-off-by:
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Chuck Lever authored
Clean up. The "ia" argument is no longer used. Signed-off-by:
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Chuck Lever authored
Currently, each regbuf is allocated and DMA mapped at the same time. This is done during transport creation. When a device driver is unloaded, every DMA-mapped buffer in use by a transport has to be unmapped, and then remapped to the new device if the driver is loaded again. Remapping will have to be done _after_ the connect worker has set up the new device. But there's an ordering problem: call_allocate, which invokes xprt_rdma_allocate which calls rpcrdma_alloc_regbuf to allocate Send buffers, happens _before_ the connect worker can run to set up the new device. Instead, at transport creation, allocate each buffer, but leave it unmapped. Once the RPC carries these buffers into ->send_request, by which time a transport connection should have been established, check to see that the RPC's buffers have been DMA mapped. If not, map them there. When device driver unplug support is added, it will simply unmap all the transport's regbufs, but it doesn't have to deallocate the underlying memory. Signed-off-by:
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Chuck Lever authored
The use of DMA_BIDIRECTIONAL is discouraged by DMA-API.txt. Fortunately, xprtrdma now knows which direction I/O is going as soon as it allocates each regbuf. The RPC Call and Reply buffers are no longer the same regbuf. They can each be labeled correctly now. The RPC Reply buffer is never part of either a Send or Receive WR, but it can be part of Reply chunk, which is mapped and registered via ->ro_map . So it is not DMA mapped when it is allocated (DMA_NONE), to avoid a double- mapping. Since Receive buffers are no longer DMA_BIDIRECTIONAL and their contents are never modified by the host CPU, DMA-API-HOWTO.txt suggests that a DMA sync before posting each buffer should be unnecessary. (See my_card_interrupt_handler). Signed-off-by:
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Chuck Lever authored
Commit 94931746 ("xprtrdma: Limit number of RDMA segments in RPC-over-RDMA headers") capped the number of chunks that may appear in RPC-over-RDMA headers. The maximum header size can be estimated and fixed to avoid allocating buffer space that is never used. Signed-off-by:
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Chuck Lever authored
RPC-over-RDMA needs to separate its RPC call and reply buffers. o When an RPC Call is sent, rq_snd_buf is DMA mapped for an RDMA Send operation using DMA_TO_DEVICE o If the client expects a large RPC reply, it DMA maps rq_rcv_buf as part of a Reply chunk using DMA_FROM_DEVICE The two mappings are for data movement in opposite directions. DMA-API.txt suggests that if these mappings share a DMA cacheline, bad things can happen. This could occur in the final bytes of rq_snd_buf and the first bytes of rq_rcv_buf if the two buffers happen to share a DMA cacheline. On x86_64 the cacheline size is typically 8 bytes, and RPC call messages are usually much smaller than the send buffer, so this hasn't been a noticeable problem. But the DMA cacheline size can be larger on other platforms. Also, often rq_rcv_buf starts most of the way into a page, thus an additional RDMA segment is needed to map and register the end of that buffer. Try to avoid that scenario to reduce the cost of registering and invalidating Reply chunks. Instead of carrying a single regbuf that covers both rq_snd_buf and rq_rcv_buf, each struct rpcrdma_req now carries one regbuf for rq_snd_buf and one regbuf for rq_rcv_buf. Some incidental changes worth noting: - To clear out some spaghetti, refactor xprt_rdma_allocate. - The value stored in rg_size is the same as the value stored in the iov.length field, so eliminate rg_size Signed-off-by:
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Chuck Lever authored
Currently there's a hidden and indirect mechanism for finding the rpcrdma_req that goes with an rpc_rqst. It depends on getting from the rq_buffer pointer in struct rpc_rqst to the struct rpcrdma_regbuf that controls that buffer, and then to the struct rpcrdma_req it goes with. This was done back in the day to avoid the need to add a per-rqst pointer or to alter the buf_free API when support for RPC-over-RDMA was introduced. I'm about to change the way regbuf's work to support larger inline thresholds. Now is a good time to replace this indirect mechanism with something that is more straightforward. I guess this should be considered a clean up. Signed-off-by:
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Chuck Lever authored
For xprtrdma, the RPC Call and Reply buffers are involved in real I/O operations. To start with, the DMA direction of the I/O for a Call is opposite that of a Reply. In the current arrangement, the Reply buffer address is on a four-byte alignment just past the call buffer. Would be friendlier on some platforms if that was at a DMA cache alignment instead. Because the current arrangement allocates a single memory region which contains both buffers, the RPC Reply buffer often contains a page boundary in it when the Call buffer is large enough (which is frequent). It would be a little nicer for setting up DMA operations (and possible registration of the Reply buffer) if the two buffers were separated, well-aligned, and contained as few page boundaries as possible. Now, I could just pad out the single memory region used for the pair of buffers. But frequently that would mean a lot of unused space to ensure the Reply buffer did not have a page boundary. Add a separate pointer to rpc_rqst that points right to the RPC Reply buffer. This makes no difference to xprtsock, but it will help xprtrdma in subsequent patches. Signed-off-by:
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