From patchwork Wed Apr 6 23:04:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12804175 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E6553C433EF for ; Wed, 6 Apr 2022 23:05:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237728AbiDFXHV (ORCPT ); Wed, 6 Apr 2022 19:07:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236876AbiDFXGu (ORCPT ); Wed, 6 Apr 2022 19:06:50 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 05F1035DC3 for ; Wed, 6 Apr 2022 16:04:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1649286289; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BjHbjuuUisNCPT/xtpNzcux3YZ1iwKXDS5qZXzwdOEE=; b=Q9Jlu/GGSRxviFnXI7aJLSep1KXbqbBclSFLEvLOeSYjp7zYfQMqKblw2qF/pjl4iPG9sv fYwwn2e0Nr/77ogZrJVkiBItUW70trjk+FP1l5OtVd114Snx5jsBYXSpY2swhSrTEFtDo/ 0znlVqaVR45CJOBmlsjZgT3bo5tZyBE= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-275-PRKxymtOMq-cIby0OiIwDQ-1; Wed, 06 Apr 2022 19:04:46 -0400 X-MC-Unique: PRKxymtOMq-cIby0OiIwDQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D1BF21C07846; Wed, 6 Apr 2022 23:04:45 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.37.45]) by smtp.corp.redhat.com (Postfix) with ESMTP id 70BFC145B973; Wed, 6 Apr 2022 23:04:44 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 11/14] cifs: Clamp length according to credits and rsize From: David Howells To: linux-cachefs@redhat.com Cc: Steve French , Shyam Prasad N , Rohith Surabattula , linux-cifs@vger.kernel.org, dhowells@redhat.com, Steve French , Shyam Prasad N , Rohith Surabattula , Jeff Layton , linux-cifs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Date: Thu, 07 Apr 2022 00:04:43 +0100 Message-ID: <164928628373.457102.3447384159737994076.stgit@warthog.procyon.org.uk> In-Reply-To: <164928615045.457102.10607899252434268982.stgit@warthog.procyon.org.uk> References: <164928615045.457102.10607899252434268982.stgit@warthog.procyon.org.uk> User-Agent: StGit/1.4 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org A read request can get expanded beyond the capacity of the available credits and rsize, so use the ->clamp_length() method to cut the request up into pieces rather than trying to do it in ->issue_read(), at which point the subrequest size is already determined. Signed-off-by: David Howells cc: Steve French cc: Shyam Prasad N cc: Rohith Surabattula cc: linux-cifs@vger.kernel.org --- fs/cifs/cifsglob.h | 2 + fs/cifs/file.c | 71 ++++++++++++++++++++++++++++++++++++---------------- fs/cifs/smb2pdu.c | 5 ++-- 3 files changed, 54 insertions(+), 24 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index e1e77225d634..2b1930a918b0 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -1328,8 +1328,10 @@ struct cifs_io_subrequest { __u64 offset; ssize_t got_bytes; unsigned int bytes; + unsigned int xid; pid_t pid; int result; + bool have_credits; struct kvec iov[2]; struct TCP_Server_Info *server; #ifdef CONFIG_CIFS_SMB_DIRECT diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 45510bd1f702..12663d9d1e51 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -3437,6 +3437,47 @@ int cifs_file_mmap(struct file *file, struct vm_area_struct *vma) return rc; } +/* + * Split the read up according to how many credits we can get for each piece. + * It's okay to sleep here if we need to wait for more credit to become + * available. + * + * We also choose the server and allocate an operation ID to be cleaned up + * later. + */ +static bool cifs_clamp_length(struct netfs_io_subrequest *subreq) +{ + struct netfs_io_request *rreq = subreq->rreq; + struct TCP_Server_Info *server; + struct cifs_io_subrequest *rdata = container_of(subreq, struct cifs_io_subrequest, subreq); + struct cifs_io_request *req = container_of(subreq->rreq, struct cifs_io_request, rreq); + struct cifs_sb_info *cifs_sb = CIFS_SB(rreq->inode->i_sb); + unsigned int rsize = 0; + int rc; + + rdata->xid = get_xid(); + + server = cifs_pick_channel(tlink_tcon(req->cfile->tlink)->ses); + rdata->server = server; + + if (cifs_sb->ctx->rsize == 0) + cifs_sb->ctx->rsize = + server->ops->negotiate_rsize(tlink_tcon(req->cfile->tlink), + cifs_sb->ctx); + + + rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize, &rsize, + &rdata->credits); + if (rc) { + subreq->error = rc; + return false; + } + + rdata->have_credits = true; + subreq->len = min_t(size_t, subreq->len, rsize); + return true; +} + /* * Issue a read operation on behalf of the netfs helper functions. We're asked * to make a read of a certain size at a point in the file. We are permitted @@ -3446,24 +3487,17 @@ int cifs_file_mmap(struct file *file, struct vm_area_struct *vma) static void cifs_req_issue_read(struct netfs_io_subrequest *subreq) { struct netfs_io_request *rreq = subreq->rreq; - struct TCP_Server_Info *server; struct cifs_io_subrequest *rdata = container_of(subreq, struct cifs_io_subrequest, subreq); struct cifs_io_request *req = container_of(subreq->rreq, struct cifs_io_request, rreq); struct cifs_sb_info *cifs_sb = CIFS_SB(rreq->inode->i_sb); - unsigned int xid; pid_t pid; int rc = 0; - unsigned int rsize; - - xid = get_xid(); if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD) pid = req->cfile->pid; else pid = current->tgid; // Ummm... This may be a workqueue - server = cifs_pick_channel(tlink_tcon(req->cfile->tlink)->ses); - cifs_dbg(FYI, "%s: op=%08x[%x] mapping=%p len=%zu/%zu\n", __func__, rreq->debug_id, subreq->debug_index, rreq->mapping, subreq->transferred, subreq->len); @@ -3476,32 +3510,20 @@ static void cifs_req_issue_read(struct netfs_io_subrequest *subreq) goto out; } - if (cifs_sb->ctx->rsize == 0) - cifs_sb->ctx->rsize = - server->ops->negotiate_rsize(tlink_tcon(req->cfile->tlink), - cifs_sb->ctx); - - rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize, &rsize, - &rdata->credits); - if (rc) - goto out; - __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags); - rdata->server = server; rdata->offset = subreq->start + subreq->transferred; rdata->bytes = subreq->len - subreq->transferred; rdata->pid = pid; - rc = adjust_credits(server, &rdata->credits, rdata->bytes); + rc = adjust_credits(rdata->server, &rdata->credits, rdata->bytes); if (!rc) { if (rdata->req->cfile->invalidHandle) rc = -EAGAIN; else - rc = server->ops->async_readv(rdata); + rc = rdata->server->ops->async_readv(rdata); } out: - free_xid(xid); if (rc) netfs_subreq_terminated(subreq, rc, false); } @@ -3580,6 +3602,7 @@ static void cifs_free_subrequest(struct netfs_io_subrequest *subreq) { struct cifs_io_subrequest *rdata = container_of(subreq, struct cifs_io_subrequest, subreq); + int rc; if (rdata->subreq.source == NETFS_DOWNLOAD_FROM_SERVER) { #ifdef CONFIG_CIFS_SMB_DIRECT @@ -3589,7 +3612,10 @@ static void cifs_free_subrequest(struct netfs_io_subrequest *subreq) } #endif - add_credits_and_wake_if(rdata->server, &rdata->credits, 0); + if (rdata->have_credits) + add_credits_and_wake_if(rdata->server, &rdata->credits, 0); + rc = subreq->error; + free_xid(rdata->xid); } } @@ -3601,6 +3627,7 @@ const struct netfs_request_ops cifs_req_ops = { .free_subrequest = cifs_free_subrequest, .begin_cache_operation = cifs_begin_cache_operation, .expand_readahead = cifs_expand_readahead, + .clamp_length = cifs_clamp_length, .issue_read = cifs_req_issue_read, .done = cifs_rreq_done, }; diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 6a8aaa003e54..952f242bee55 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -4174,7 +4174,7 @@ smb2_readv_callback(struct mid_q_entry *mid) #endif if (rdata->result && rdata->result != -ENODATA) { cifs_stats_fail_inc(tcon, SMB2_READ_HE); - trace_smb3_read_err(0 /* xid */, + trace_smb3_read_err(rdata->xid, rdata->req->cfile->fid.persistent_fid, tcon->tid, tcon->ses->Suid, rdata->offset, rdata->bytes, rdata->result); @@ -4193,6 +4193,7 @@ smb2_readv_callback(struct mid_q_entry *mid) } if (rdata->result == 0 || rdata->result == -EAGAIN) iov_iter_advance(&rdata->subreq.iter, rdata->got_bytes); + rdata->have_credits = false; netfs_subreq_terminated(&rdata->subreq, (rdata->result == 0 || rdata->result == -EAGAIN) ? rdata->got_bytes : rdata->result, true); @@ -4259,7 +4260,7 @@ smb2_async_readv(struct cifs_io_subrequest *rdata) &rdata->credits); if (rc) { cifs_stats_fail_inc(io_parms.tcon, SMB2_READ_HE); - trace_smb3_read_err(0 /* xid */, io_parms.persistent_fid, + trace_smb3_read_err(rdata->xid, io_parms.persistent_fid, io_parms.tcon->tid, io_parms.tcon->ses->Suid, io_parms.offset, io_parms.length, rc);