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 77AFD245019 for ; Thu, 31 Jul 2025 19:44:53 +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=1753991093; cv=none; b=n+mBRxeDahsGnZ8x5atF5nVdoTFzVVxbMPWSZTWPmeg4GqTLVssTCVfqqlVRnevERvSbXYvqZha24C1RXWMgeKdLreIXQwC7IPq9PYlkk8xKOi+LHf+2LjgsudvXEDQ/8y60BOtxcZ18ycLVpujGCGT/olc0IncNW+int2MN+ZI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753991093; c=relaxed/simple; bh=RhU5+Ilsb7ntVQKw6ldTMviDEBQ11kXJ01nSI5kXBiI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=n5x01kXJlzvdCnbcvxVY76qGW9X7Dm7GvJlk7kMslOf09JTui6p+iXb5iE/2nzRzBbYOyU9/pYWPiVauBG/Wb08UmM4Pt/9wSrPQ3kivfc7sh/KaZmfCucRNED0Er6nI9pz0sCcRAwYakDlnT3Zp/zFTz6b4n5aGIACHIiNjJP0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fOorJoiU; 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="fOorJoiU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B4999C4CEEF; Thu, 31 Jul 2025 19:44:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753991093; bh=RhU5+Ilsb7ntVQKw6ldTMviDEBQ11kXJ01nSI5kXBiI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fOorJoiU0sWgI6o/YEeFF1feC02trlh2ushK0Hee2x5FPBSe6Nta/uUapmu+ZH6jg ENv0Xh8hdf7pf4/stFUxJQDBuNK1kit7OPPYX168AKOT2PSasz6FPw2DA2RY9SRKOg 76kelbS58LKS3qi7I8dwZXiKpZ49x/ysIMU/KMyXgUdpZ/gde8g1N4xoKsDzTwjdpE ZfkmKQW54HFK4SckqUCXdgL0kevurLMDefti5xTsfAMfH3jkolib5BRQgRYlVL3Yn3 PUx0/vNDDCL5KwA/Xl5jMsHl6rgJU4SBpPxJqIzzr/G3aZFWYsKGlFb0iMphbz+zKg ldQB2r2qVyV4w== From: Mike Snitzer To: Chuck Lever , Jeff Layton Cc: linux-nfs@vger.kernel.org Subject: [PATCH v2 2/4] NFSD: prepare nfsd_vfs_write() to use O_DIRECT on misaligned WRITEs Date: Thu, 31 Jul 2025 15:44:46 -0400 Message-ID: <20250731194448.88816-3-snitzer@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20250731194448.88816-1-snitzer@kernel.org> References: <20250731194448.88816-1-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 --- fs/nfsd/vfs.c | 50 ++++++++++++++++++++++++++++++-------------------- 1 file changed, 30 insertions(+), 20 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 35c29b8ade9c3..e4855c32dad12 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; @@ -1396,25 +1399,32 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, break; } - 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; + *cnt = 0; + for (int i = 0; i < n_iters; i++) { + since = READ_ONCE(file->f_wb_err); + if (verf) + nfsd_copy_write_verifier(verf, nn); - if (stable && fhp->fh_use_wgather) { - host_err = wait_for_concurrent_writes(file); - if (host_err < 0) + 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