From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 99A1F329E55 for ; Tue, 16 Jun 2026 13:40:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781617213; cv=none; b=fJQ6c9C6oluVG6L64qM4LFb9ttwQlAguXBFeBYK1phVSyxa3jsBZ99twNyiJrgOFD9naL4kc3Rsmyct5o8KaTH7XiayWM7pn1Qns3aW4JqtwBzTJmweLNQOT5pI+iLQUygwSSjUH2BFH6wXRw/7XJNmUz2Kj1uDa74OY0IPU0iw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781617213; c=relaxed/simple; bh=+HQMNksOcX7c5Z4Lj1ZiFTOb9K6NNwdea51nx/nZUHY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=iCFI1fiRUU6f01mKfEpOYX0+FSbhFM7m/NR5h3kvMc5N5hrhYTlkVO+gBBJB/jpNpoGBIcXIbBAmkEXXl1oxfZLMNseB3uMxdofebuCe3MI1yO2IleyvzSzPgN4fSMFKHVPyCuZmzbsFaHSwiq6BG7XmVHocDw9bPqkHAjUlNds= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--praan.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=JbVrMOnZ; arc=none smtp.client-ip=209.85.210.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--praan.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="JbVrMOnZ" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-8421ffff8a3so5898351b3a.2 for ; Tue, 16 Jun 2026 06:40:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781617212; x=1782222012; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=f9kNSBUvswlwhXTj/UXo/ji00jjc4pWqkan8sffXzzE=; b=JbVrMOnZV3TYnAhpAL136auPzSuY84xI90VUvmpz/Y1MzPEuWUSm5yz4CGSieYr4Ld 4qN+PLFSvHZVsigatAQzqA69KA3APUbWI5J48qxs0ljxb1iO60hmJ4vbA41AWnLUDhPk ptu/mREzlHYDdrTaBwBYex6UVNTq1UMtG24GjjA5MYPMuxJcK+3318Tcchzthli36j4Z QP3PBUmhd9t5BBQjCAe2MrGaSoUZoHIbUimmkfRino0EsG7xzCR8iimPa49QNaYKCUTK hrhEQ3wWfZtGFoQFOOA+rHXw9xuFrOU/zJAP5wOXciViSFpvlZ88dlYTqP/9cK3uwKuy bDcQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781617212; x=1782222012; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=f9kNSBUvswlwhXTj/UXo/ji00jjc4pWqkan8sffXzzE=; b=IvsYJy8R3iXuR2d5CAboxSIAczSv6oueWiYx9dRdHOW5ylkDMZSHT7xbGX7tSj39Py NcGyULp84sAiBF+Ml7sVADsQ9hF6PtW4mbwiR+BHLSCCCpeEAfZ2b9P6BCCcXbjRGD8p +47rmUoCVrwZemzkOD4Nxnme7jtVu61lwwMpDpUvVqzgY1G1TJkJa8pTr/KhIJtA2c7D G2JWfPEpRu+zPsYeUpJEfrzRNh4ifBdMhWpygxTUI2KORt25qjHpIY+1h8qpLGEJYMZR sW4+G/jjwBzqvr4VzH8uY4f+iXyQ4iI/BXwhyKxZ9p6ygscwlPO9C7IFXCMn3M0WURpz M44A== X-Forwarded-Encrypted: i=1; AFNElJ8vSYj6JVx+jybFLGSP+J66/q0iKjKCQTQKjZrFwSBrL0WxbivwwuilcmpGLxmmXYtTCgTiel8novRMEmE=@vger.kernel.org X-Gm-Message-State: AOJu0YyqtbUKm4DULJMUFg9iV6pivhLPmINksbROsxYARRR1USt0PTFP c0F9QiIN8Lse6SDVnaI3aaXYec+Ecea5zk5YZHGOIXXPnuLe7tEB5mp8mq5mstmCbHJyto/zYR3 IEQ== X-Received: from pfbcd14.prod.google.com ([2002:a05:6a00:420e:b0:842:54be:af42]) (user=praan job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:3d48:b0:842:5c60:513 with SMTP id d2e1a72fcca58-8434ce84647mr20718998b3a.30.1781617211619; Tue, 16 Jun 2026 06:40:11 -0700 (PDT) Date: Tue, 16 Jun 2026 13:39:57 +0000 In-Reply-To: <20260616134000.2733403-1-praan@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260616134000.2733403-1-praan@google.com> X-Mailer: git-send-email 2.54.0.1136.gdb2ca164c4-goog Message-ID: <20260616134000.2733403-5-praan@google.com> Subject: [PATCH v2 4/7] nfs: migrate direct I/O to iov_iter_extract_pages From: Pranjal Shrivastava To: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Trond Myklebust , Anna Schumaker , Christoph Hellwig , Christoph Hellwig , Shivaji Kant , Pranjal Shrivastava Content-Type: text/plain; charset="UTF-8" Migrate the NFS Direct I/O path away from the legacy iov_iter_get_pages_alloc2() API to the modern iov_iter_extract_pages API. The transition aligns NFS with the modern VFS extraction model and serves as a preparatory step for supporting requirements such as page pinning via GUP for DMA. The migration fixes a bug in the Direct I/O loop where pages were being unpinned immediately after request creation. With the new extraction model, pins are held until the I/O is complete. Manual release in the loop is correspondingly updated to only clean up failed pages. Signed-off-by: Pranjal Shrivastava --- fs/nfs/direct.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 96995736fac2..b9ac0a67693c 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -354,16 +354,17 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq, inode_dio_begin(inode); while (iov_iter_count(iter)) { - struct page **pagevec; + struct page **pagevec = NULL; size_t bytes; size_t pgbase; unsigned npages, i; + bool pinned = iov_iter_extract_will_pin(iter); - result = iov_iter_get_pages_alloc2(iter, &pagevec, - rsize, &pgbase); + result = iov_iter_extract_pages(iter, &pagevec, + rsize, ~0U, 0, &pgbase); if (result < 0) break; - + bytes = result; npages = (result + pgbase + PAGE_SIZE - 1) / PAGE_SIZE; for (i = 0; i < npages; i++) { @@ -371,7 +372,7 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq, unsigned int req_len = min_t(size_t, bytes, PAGE_SIZE - pgbase); /* XXX do we need to do the eof zeroing found in async_filler? */ req = nfs_page_create_from_page(dreq->ctx, pagevec[i], - false, pgbase, pos, + pinned, pgbase, pos, req_len); if (IS_ERR(req)) { result = PTR_ERR(req); @@ -387,7 +388,8 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq, requested_bytes += req_len; pos += req_len; } - nfs_direct_release_pages(pagevec, npages, false); + if (i < npages) + nfs_direct_release_pages(pagevec + i, npages - i, pinned); kvfree(pagevec); if (result < 0) break; @@ -891,13 +893,14 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq, NFS_I(inode)->write_io += iov_iter_count(iter); while (iov_iter_count(iter)) { - struct page **pagevec; + struct page **pagevec = NULL; size_t bytes; size_t pgbase; unsigned npages, i; + bool pinned = iov_iter_extract_will_pin(iter); - result = iov_iter_get_pages_alloc2(iter, &pagevec, - wsize, &pgbase); + result = iov_iter_extract_pages(iter, &pagevec, + wsize, ~0U, 0, &pgbase); if (result < 0) break; @@ -908,7 +911,7 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq, unsigned int req_len = min_t(size_t, bytes, PAGE_SIZE - pgbase); req = nfs_page_create_from_page(dreq->ctx, pagevec[i], - false, pgbase, pos, + pinned, pgbase, pos, req_len); if (IS_ERR(req)) { result = PTR_ERR(req); @@ -952,7 +955,8 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq, desc.pg_error = 0; defer = true; } - nfs_direct_release_pages(pagevec, npages, false); + if (i < npages) + nfs_direct_release_pages(pagevec + i, npages - i, pinned); kvfree(pagevec); if (result < 0) break; -- 2.54.0.1136.gdb2ca164c4-goog