From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 364711E32CF for ; Mon, 13 Oct 2025 19:01:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760382077; cv=none; b=RBj1F/yykVyoAJarxGUyyeKx5QZ5KuZ1BY4EpuWX9mAnGBDLD3aatauwKUfdmitboTevZVAJAHMs6wRzfSsFYxfggUHTDeFv5WbOukwYWLP6WM+buP3wYx9nWsD2h9sra79tOwixZ3rZydEoALKFmtzdE8OC6SJdcsfzthPetO4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760382077; c=relaxed/simple; bh=AuDMUQ0BNrafK3DDOfhsEOrVuDWS8YnzeFfX4WL/FGM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=rAk1klrX4gXBKuqYXBEIQRA5C0WVqvuXXN3ptlJFPL6pxYu3/88MDt8CzRhBuV+iRBPxXgBvXbUthf1NjXkBI+hlsoz8wuCLCLPzLhN4gtBTbVCrzq0B/DZnyPhdNh2Fm9owtWeKtEsqeaIC7T65WpnjlppUqPrvrGkyhvJSvso= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=u5hj6Lca; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="u5hj6Lca" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16DF6C4CEE7; Mon, 13 Oct 2025 19:01:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760382076; bh=AuDMUQ0BNrafK3DDOfhsEOrVuDWS8YnzeFfX4WL/FGM=; h=From:To:Cc:Subject:Date:From; b=u5hj6LcaqDiK6c3YqIK6cE4xW4363tIPnR4hb0pfGzvyZzgGrdvgWwL0KApYR50A8 90ZJHEFZx8DuTh2jAmYdCkleBQ+03RRxYuSQwegHMh2xBh6GmY0K6dFiAU8UIy1s9Z 6c0hU04tDBw0umpyf7cO0nPLd26vwGB/9pFlcb6END+E/05PxsSEgaWoXUv7Gsosk/ CbS9Rt8cIuOJ8lknhkFEjXKUWAWR6jpS0HRqyFFc+jzAAcUqc0h8BbeNelSnkgM9IW /8R1tofpe4RTBbFCuuutxg2sXRx/d7hjZdrr92aTiz/RTcVrp9J0VQx1E8wyE9tM84 4b3LaLWYLDMzQ== From: Chuck Lever To: NeilBrown , Jeff Layton , Olga Kornievskaia , Dai Ngo , Tom Talpey Cc: , Mike Snitzer , Chuck Lever Subject: [PATCH v1] NFSD: Enable return of an updated stable_how to NFS clients Date: Mon, 13 Oct 2025 15:01:13 -0400 Message-ID: <20251013190113.252097-1-cel@kernel.org> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Chuck Lever In a subsequent patch, nfsd_vfs_write() will promote an UNSTABLE WRITE to be a FILE_SYNC WRITE. This indicates that the client does not need a subsequent COMMIT operation, saving a round trip and allowing the client to dispense with cached dirty data as soon as it receives the server's WRITE response. This patch refactors nfsd_vfs_write() to return a possibly modified stable_how value to its callers. No behavior change is expected. Signed-off-by: Chuck Lever --- fs/nfsd/nfs3proc.c | 2 +- fs/nfsd/nfs4proc.c | 2 +- fs/nfsd/nfsproc.c | 3 ++- fs/nfsd/vfs.c | 11 ++++++----- fs/nfsd/vfs.h | 6 ++++-- fs/nfsd/xdr3.h | 2 +- 6 files changed, 15 insertions(+), 11 deletions(-) Here's what I had in mind, based on a patch I did a year ago but never posted. If nfsd_vfs_write() promotes an NFS_UNSTABLE write to NFS_FILE_SYNC, it can now set *stable_how and the WRITE encoders will return the updated value to the client. diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index b6d03e1ef5f7..ad14b34583bb 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -236,7 +236,7 @@ nfsd3_proc_write(struct svc_rqst *rqstp) resp->committed = argp->stable; resp->status = nfsd_write(rqstp, &resp->fh, argp->offset, &argp->payload, &cnt, - resp->committed, resp->verf); + &resp->committed, resp->verf); resp->count = cnt; resp->status = nfsd3_map_status(resp->status); return rpc_success; diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 7f7e6bb23a90..2222bb283baf 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1285,7 +1285,7 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, write->wr_how_written = write->wr_stable_how; status = nfsd_vfs_write(rqstp, &cstate->current_fh, nf, write->wr_offset, &write->wr_payload, - &cnt, write->wr_how_written, + &cnt, &write->wr_how_written, (__be32 *)write->wr_verifier.data); nfsd_file_put(nf); diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c index 8f71f5748c75..706401ed6f8d 100644 --- a/fs/nfsd/nfsproc.c +++ b/fs/nfsd/nfsproc.c @@ -251,6 +251,7 @@ nfsd_proc_write(struct svc_rqst *rqstp) struct nfsd_writeargs *argp = rqstp->rq_argp; struct nfsd_attrstat *resp = rqstp->rq_resp; unsigned long cnt = argp->len; + u32 committed = NFS_DATA_SYNC; dprintk("nfsd: WRITE %s %u bytes at %d\n", SVCFH_fmt(&argp->fh), @@ -258,7 +259,7 @@ nfsd_proc_write(struct svc_rqst *rqstp) fh_copy(&resp->fh, &argp->fh); resp->status = nfsd_write(rqstp, &resp->fh, argp->offset, - &argp->payload, &cnt, NFS_DATA_SYNC, NULL); + &argp->payload, &cnt, &committed, NULL); if (resp->status == nfs_ok) resp->status = fh_getattr(&resp->fh, &resp->stat); else if (resp->status == nfserr_jukebox) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index f537a7b4ee01..8b2dc7a88aab 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1262,7 +1262,7 @@ static int wait_for_concurrent_writes(struct file *file) * @offset: Byte offset of start * @payload: xdr_buf containing the write payload * @cnt: IN: number of bytes to write, OUT: number of bytes actually written - * @stable: An NFS stable_how value + * @stable_how: IN: Client's requested stable_how, OUT: Actual stable_how * @verf: NFS WRITE verifier * * Upon return, caller must invoke fh_put on @fhp. @@ -1274,11 +1274,12 @@ __be32 nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf, loff_t offset, const struct xdr_buf *payload, unsigned long *cnt, - int stable, __be32 *verf) + u32 *stable_how, __be32 *verf) { struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); struct file *file = nf->nf_file; struct super_block *sb = file_inode(file)->i_sb; + u32 stable = *stable_how; struct kiocb kiocb; struct svc_export *exp; struct iov_iter iter; @@ -1434,7 +1435,7 @@ __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, * @offset: Byte offset of start * @payload: xdr_buf containing the write payload * @cnt: IN: number of bytes to write, OUT: number of bytes actually written - * @stable: An NFS stable_how value + * @stable_how: IN: Client's requested stable_how, OUT: Actual stable_how * @verf: NFS WRITE verifier * * Upon return, caller must invoke fh_put on @fhp. @@ -1444,7 +1445,7 @@ __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, */ __be32 nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset, - const struct xdr_buf *payload, unsigned long *cnt, int stable, + const struct xdr_buf *payload, unsigned long *cnt, u32 *stable_how, __be32 *verf) { struct nfsd_file *nf; @@ -1457,7 +1458,7 @@ nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset, goto out; err = nfsd_vfs_write(rqstp, fhp, nf, offset, payload, cnt, - stable, verf); + stable_how, verf); nfsd_file_put(nf); out: trace_nfsd_write_done(rqstp, fhp, offset, *cnt); diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h index fa46f8b5f132..c713ed0b04e0 100644 --- a/fs/nfsd/vfs.h +++ b/fs/nfsd/vfs.h @@ -130,11 +130,13 @@ __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *eof); __be32 nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset, const struct xdr_buf *payload, - unsigned long *cnt, int stable, __be32 *verf); + unsigned long *cnt, u32 *stable_how, + __be32 *verf); __be32 nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf, loff_t offset, const struct xdr_buf *payload, - unsigned long *cnt, int stable, __be32 *verf); + unsigned long *cnt, u32 *stable_how, + __be32 *verf); __be32 nfsd_readlink(struct svc_rqst *, struct svc_fh *, char *, int *); __be32 nfsd_symlink(struct svc_rqst *, struct svc_fh *, diff --git a/fs/nfsd/xdr3.h b/fs/nfsd/xdr3.h index 522067b7fd75..c0e443ef3a6b 100644 --- a/fs/nfsd/xdr3.h +++ b/fs/nfsd/xdr3.h @@ -152,7 +152,7 @@ struct nfsd3_writeres { __be32 status; struct svc_fh fh; unsigned long count; - int committed; + u32 committed; __be32 verf[2]; }; -- 2.51.0