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 802DC153598 for ; Thu, 31 Jul 2025 23:06:37 +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=1754003197; cv=none; b=KJwhHDHynG+h2xSQnWcqmNH9cosCKQQf2gtvzUVUibEK9wKSbEA9n1fKn7OlFcNVTifnF9nTXe8D78MUOV9hom4QpdGuODQvyyrNbrO5DKXZDalq4fj8fXRKLpylGVdpv9FDNsD4WOE5SP10zvX6gqYD6DJklapRfx9OFdVAhvY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754003197; c=relaxed/simple; bh=eKuEixWDVq9OldXimEYZ3xtWOL3tdlqcS+iZYvaH3VM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=U1jRKvtsvy4e9QtVnJy4B5zKpPzbcVxI5n2D0ULByH8i7gispFvdYmy/8Usfi0Aqx+jmTEjpDsmd70f+o/f+YKCakWBL7i2pdn8gDQc5733F/7b7RWmRvqaPjO5arfy4EqIvB0d6kPAy7FAYmhA64BbquQ+lSe2adEG8ZHMVBS0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qutaCdFu; 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="qutaCdFu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B4A7C4CEF7; Thu, 31 Jul 2025 23:06:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1754003197; bh=eKuEixWDVq9OldXimEYZ3xtWOL3tdlqcS+iZYvaH3VM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qutaCdFuhfF90WntOS8W+zwpcJQaMS1lTyw1fR1x84eaqutAEfARr2YnjexEBXzRc vVXQW7Clk0/vIwEFcBSjWwqvlgO1DKHVgDiNGTFRN9uvGScPeQMuzGeiDpmGvYF5p2 xmFrCp9sLZ1H0fqkj5IO9Us4UC9nAxMicoyS8YkvVTna9IT/mg03mKdv7tku8MMfA2 ffcNq7UMg+HDZEu/OYnhFu5VCACQITf+jkipWPpvm1T/bLKt1AF/RV9IQ3AgIUjQGI rYCFmHmCakGFg8NfIe6Dg231WNQGFSHjYV/eqqxF3X1xbk1xkukbPn6fpkjVI04dAe fbxDLCIw8jJXg== From: Mike Snitzer To: Chuck Lever , Jeff Layton Cc: linux-nfs@vger.kernel.org Subject: [PATCH v3 2/4] NFSD: prepare nfsd_vfs_write() to use O_DIRECT on misaligned WRITEs Date: Thu, 31 Jul 2025 19:06:31 -0400 Message-ID: <20250731230633.89983-3-snitzer@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20250731230633.89983-1-snitzer@kernel.org> References: <20250731230633.89983-1-snitzer@kernel.org> Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Refactor nfsd_vfs_write() to support splitting a WRITE into parts (which will be either misaligned or DIO-aligned). Doing so in a preliminary commit just allows for indentation and slight transformation to be more easily understood and reviewed. Signed-off-by: Mike Snitzer Reviewed-by: Jeff Layton --- fs/nfsd/vfs.c | 45 +++++++++++++++++++++++++++------------------ 1 file changed, 27 insertions(+), 18 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 35c29b8ade9c3..edac73349da0f 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1341,7 +1341,6 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct super_block *sb = file_inode(file)->i_sb; struct kiocb kiocb; struct svc_export *exp; - struct iov_iter iter; errseq_t since; __be32 nfserr; int host_err; @@ -1349,6 +1348,9 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned int pflags = current->flags; bool restore_flags = false; unsigned int nvecs; + struct iov_iter iter_stack[1]; + struct iov_iter *iter = iter_stack; + unsigned int n_iters = 0; trace_nfsd_write_opened(rqstp, fhp, offset, *cnt); @@ -1378,14 +1380,15 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, kiocb.ki_flags |= IOCB_DSYNC; nvecs = xdr_buf_to_bvec(rqstp->rq_bvec, rqstp->rq_maxpages, payload); - iov_iter_bvec(&iter, ITER_SOURCE, rqstp->rq_bvec, nvecs, *cnt); + iov_iter_bvec(&iter[0], ITER_SOURCE, rqstp->rq_bvec, nvecs, *cnt); + n_iters++; switch (nfsd_io_cache_write) { case NFSD_IO_DIRECT: /* direct I/O must be aligned to device logical sector size */ if (nf->nf_dio_mem_align && nf->nf_dio_offset_align && (((offset | *cnt) & (nf->nf_dio_offset_align-1)) == 0) && - iov_iter_is_aligned(&iter, nf->nf_dio_mem_align - 1, + iov_iter_is_aligned(&iter[0], nf->nf_dio_mem_align - 1, nf->nf_dio_offset_align - 1)) kiocb.ki_flags = IOCB_DIRECT; break; @@ -1399,22 +1402,28 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, since = READ_ONCE(file->f_wb_err); if (verf) nfsd_copy_write_verifier(verf, nn); - host_err = vfs_iocb_iter_write(file, &kiocb, &iter); - if (host_err < 0) { - commit_reset_write_verifier(nn, rqstp, host_err); - goto out_nfserr; - } - *cnt = host_err; - nfsd_stats_io_write_add(nn, exp, *cnt); - fsnotify_modify(file); - host_err = filemap_check_wb_err(file->f_mapping, since); - if (host_err < 0) - goto out_nfserr; - - if (stable && fhp->fh_use_wgather) { - host_err = wait_for_concurrent_writes(file); - if (host_err < 0) + *cnt = 0; + for (int i = 0; i < n_iters; i++) { + host_err = vfs_iocb_iter_write(file, &kiocb, &iter[i]); + if (host_err < 0) { commit_reset_write_verifier(nn, rqstp, host_err); + goto out_nfserr; + } + *cnt += host_err; + nfsd_stats_io_write_add(nn, exp, host_err); + + fsnotify_modify(file); + host_err = filemap_check_wb_err(file->f_mapping, since); + if (host_err < 0) + goto out_nfserr; + + if (stable && fhp->fh_use_wgather) { + host_err = wait_for_concurrent_writes(file); + if (host_err < 0) { + commit_reset_write_verifier(nn, rqstp, host_err); + goto out_nfserr; + } + } } out_nfserr: -- 2.44.0