From patchwork Tue Apr 30 14:00:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 793390 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 08A6B1C2324 for ; Tue, 30 Apr 2024 14:03:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714485793; cv=none; b=kVds6R6s19OemEOOhK6Y9BXvW4kyPDmdDQKKPF09Rx2ynEA19XDFTgPMds/MKhDmTqoEA2oF9pM/jdU8fwkfraJvlA5uuUq+C87Yw1WBbkS5mp4gv0KrNaFoF15i+cJtqUsIoMMb0B+LgmMdZcQpS40SkqKGwAevE57q4YKh4JA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714485793; c=relaxed/simple; bh=01uPlYp+gvlCfzslwRki94T9N2SRBI4xvdjRNvc/FwA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TaGTDCv68ACqKeSqClU7528UJG2zVqtrP/xqgA/aRyPtuvsamEevWyY+XoTN1LJQvX3y4TQvO8J59Cg5Wf63Qugi5gjOTMVrClceBpT4MA78+cbg4naPeBBTdi22jwDJANJglHuCCVI9Jmqob+ctcleZyZ6WnwFvyXGz/Zf99iU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=aeK/WMd4; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="aeK/WMd4" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1714485787; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vGCt48jeC555R9pX52pBDvHMiG4CZMcxlPULZd6gPmg=; b=aeK/WMd4WCU+TUROwzHshbSgMF5N4nxiUCRRaR9cEDmf4lyJeJSRs/CnCzYL0xAOMynwTn QsgD8peOrFi6ENtOvHhj+ugw/LvsQd1N2TU7JlR80G5NA1y2ezDRq3DnV5vI8dHG64sbdE 43pRGLNU6cKt5IqXVPlCNzyR1sOxO7M= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-118-SoCcPPCCPq6LefypiSX-qA-1; Tue, 30 Apr 2024 10:02:56 -0400 X-MC-Unique: SoCcPPCCPq6LefypiSX-qA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0ADA788294A; Tue, 30 Apr 2024 14:02:16 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.42.28.22]) by smtp.corp.redhat.com (Postfix) with ESMTP id D1AD6EC680; Tue, 30 Apr 2024 14:02:12 +0000 (UTC) From: David Howells To: Christian Brauner , Jeff Layton , Gao Xiang , Dominique Martinet Cc: David Howells , Matthew Wilcox , Steve French , Marc Dionne , Paulo Alcantara , Shyam Prasad N , Tom Talpey , Eric Van Hensbergen , Ilya Dryomov , netfs@lists.linux.dev, linux-cachefs@redhat.com, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs@lists.linux.dev, linux-erofs@lists.ozlabs.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Latchesar Ionkov , Christian Schoenebeck Subject: [PATCH v2 17/22] netfs, 9p: Implement helpers for new write code Date: Tue, 30 Apr 2024 15:00:48 +0100 Message-ID: <20240430140056.261997-18-dhowells@redhat.com> In-Reply-To: <20240430140056.261997-1-dhowells@redhat.com> References: <20240430140056.261997-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: ceph-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 Implement the helpers for the new write code in 9p. There's now an optional ->prepare_write() that allows the filesystem to set the parameters for the next write, such as maximum size and maximum segment count, and an ->issue_write() that is called to initiate an (asynchronous) write operation. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: Eric Van Hensbergen cc: Latchesar Ionkov cc: Dominique Martinet cc: Christian Schoenebeck cc: v9fs@lists.linux.dev cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org --- Notes: Changes ======= ver #2) - Use 'int len' rather than 'size_t len' because of the varargs packet formatter. fs/9p/vfs_addr.c | 48 ++++++++++++++++++++++++++++++++++++++++ include/net/9p/client.h | 2 ++ net/9p/Kconfig | 1 + net/9p/client.c | 49 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 100 insertions(+) diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c index 5a943c122d83..07d03efdd594 100644 --- a/fs/9p/vfs_addr.c +++ b/fs/9p/vfs_addr.c @@ -26,6 +26,40 @@ #include "cache.h" #include "fid.h" +/* + * Writeback calls this when it finds a folio that needs uploading. This isn't + * called if writeback only has copy-to-cache to deal with. + */ +static void v9fs_begin_writeback(struct netfs_io_request *wreq) +{ + struct p9_fid *fid; + + fid = v9fs_fid_find_inode(wreq->inode, true, INVALID_UID, true); + if (!fid) { + WARN_ONCE(1, "folio expected an open fid inode->i_ino=%lx\n", + wreq->inode->i_ino); + return; + } + + wreq->wsize = fid->clnt->msize - P9_IOHDRSZ; + if (fid->iounit) + wreq->wsize = min(wreq->wsize, fid->iounit); + wreq->netfs_priv = fid; + wreq->io_streams[0].avail = true; +} + +/* + * Issue a subrequest to write to the server. + */ +static void v9fs_issue_write(struct netfs_io_subrequest *subreq) +{ + struct p9_fid *fid = subreq->rreq->netfs_priv; + int err, len; + + len = p9_client_write(fid, subreq->start, &subreq->io_iter, &err); + netfs_write_subrequest_terminated(subreq, len ?: err, false); +} + static void v9fs_upload_to_server(struct netfs_io_subrequest *subreq) { struct p9_fid *fid = subreq->rreq->netfs_priv; @@ -92,6 +126,14 @@ static int v9fs_init_request(struct netfs_io_request *rreq, struct file *file) rreq->origin == NETFS_UNBUFFERED_WRITE || rreq->origin == NETFS_DIO_WRITE); +#if 0 // TODO: Cut over + if (rreq->origin == NETFS_WRITEBACK) + return 0; /* We don't get the write handle until we find we + * have actually dirty data and not just + * copy-to-cache data. + */ +#endif + if (file) { fid = file->private_data; if (!fid) @@ -103,6 +145,10 @@ static int v9fs_init_request(struct netfs_io_request *rreq, struct file *file) goto no_fid; } + rreq->wsize = fid->clnt->msize - P9_IOHDRSZ; + if (fid->iounit) + rreq->wsize = min(rreq->wsize, fid->iounit); + /* we might need to read from a fid that was opened write-only * for read-modify-write of page cache, use the writeback fid * for that */ @@ -131,6 +177,8 @@ const struct netfs_request_ops v9fs_req_ops = { .init_request = v9fs_init_request, .free_request = v9fs_free_request, .issue_read = v9fs_issue_read, + .begin_writeback = v9fs_begin_writeback, + .issue_write = v9fs_issue_write, .create_write_requests = v9fs_create_write_requests, }; diff --git a/include/net/9p/client.h b/include/net/9p/client.h index 78ebcf782ce5..4f785098c67a 100644 --- a/include/net/9p/client.h +++ b/include/net/9p/client.h @@ -207,6 +207,8 @@ int p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err int p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err); int p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err); +struct netfs_io_subrequest; +void p9_client_write_subreq(struct netfs_io_subrequest *subreq); int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset); int p9dirent_read(struct p9_client *clnt, char *buf, int len, struct p9_dirent *dirent); diff --git a/net/9p/Kconfig b/net/9p/Kconfig index 00ebce9e5a65..bcdab9c23b40 100644 --- a/net/9p/Kconfig +++ b/net/9p/Kconfig @@ -5,6 +5,7 @@ menuconfig NET_9P tristate "Plan 9 Resource Sharing Support (9P2000)" + select NETFS_SUPPORT help If you say Y here, you will get experimental support for Plan 9 resource sharing via the 9P2000 protocol. diff --git a/net/9p/client.c b/net/9p/client.c index f7e90b4769bb..00774656eeac 100644 --- a/net/9p/client.c +++ b/net/9p/client.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -1661,6 +1662,54 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) } EXPORT_SYMBOL(p9_client_write); +void +p9_client_write_subreq(struct netfs_io_subrequest *subreq) +{ + struct netfs_io_request *wreq = subreq->rreq; + struct p9_fid *fid = wreq->netfs_priv; + struct p9_client *clnt = fid->clnt; + struct p9_req_t *req; + unsigned long long start = subreq->start + subreq->transferred; + int written, len = subreq->len - subreq->transferred; + int err; + + p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu len %d\n", + fid->fid, start, len); + + /* Don't bother zerocopy for small IO (< 1024) */ + if (clnt->trans_mod->zc_request && len > 1024) { + req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, &subreq->io_iter, + 0, wreq->len, P9_ZC_HDR_SZ, "dqd", + fid->fid, start, len); + } else { + req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid, + start, len, &subreq->io_iter); + } + if (IS_ERR(req)) { + netfs_write_subrequest_terminated(subreq, PTR_ERR(req), false); + return; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &written); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + netfs_write_subrequest_terminated(subreq, err, false); + return; + } + + if (written > len) { + pr_err("bogus RWRITE count (%d > %u)\n", written, len); + written = len; + } + + p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", len); + + p9_req_put(clnt, req); + netfs_write_subrequest_terminated(subreq, written, false); +} +EXPORT_SYMBOL(p9_client_write_subreq); + struct p9_wstat *p9_client_stat(struct p9_fid *fid) { int err;