From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D73F4C433DF for ; Fri, 21 Aug 2020 17:27:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2C3D22BF3 for ; Fri, 21 Aug 2020 17:27:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Bj9wRRg+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728230AbgHUR1M (ORCPT ); Fri, 21 Aug 2020 13:27:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43626 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727807AbgHUR1C (ORCPT ); Fri, 21 Aug 2020 13:27:02 -0400 Received: from mail-vs1-xe42.google.com (mail-vs1-xe42.google.com [IPv6:2607:f8b0:4864:20::e42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C799C061573; Fri, 21 Aug 2020 10:27:02 -0700 (PDT) Received: by mail-vs1-xe42.google.com with SMTP id b16so868089vsl.6; Fri, 21 Aug 2020 10:27:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:reply-to:from:date:message-id :subject:to:cc:content-transfer-encoding; bh=ZJ/SgEY6vmZqsnENuzbboQsYNBFC3MlqyIs3liaUOz8=; b=Bj9wRRg+SAtCbnx135wzg9FnaNwBTJ58EScRtp5mP0abu16VpY5abDpT5pp4FW7rAQ 9hunUys45Fc95kO3MZvknCnrk+s7/KHhteSHYQDpyYB0wVVobDkWFW/2BrKKeTlUbzVq Jw2or6oMghzyYyqadV1S6ftgUcWXy0F3gsGXcZQ6O8KfS/TGgpWpPdxI2WfKVbcEcmzX NhGiC5f3b6cM38dCqCvO4NH9QuFQias+hAzGoLZPazd5USkt5LZ1cK+y0bLqUJHPKQqN WMOlc2w5jxIOkINcQ9cBhJsX6VzjwJ1RG5fbhb7Xk8jrwnOMbmn24bDJKWJ67xHRDCUH iCqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:reply-to :from:date:message-id:subject:to:cc:content-transfer-encoding; bh=ZJ/SgEY6vmZqsnENuzbboQsYNBFC3MlqyIs3liaUOz8=; b=micMsIuOf+KTKHi4MGjEJBt914qwStFXtOg/29zAO8TYm0NEIlmnDwiLVVPtpf8Xit ctGg9m0faojrupEGdJKHV0MX7QNBVG9Pw7IygPZvb1+507WShGDodTm3gJ0SDhG9e/0m jYV0wKU9Zx7zGmFZM7uVAgUvg7Fy1jGq7aA+6d1ZoHL3QQOd06cVyMnIltppLc6VDkkq 3Zj5JG3ndKkg8qEZl3Nn+tUOem9vdrLkfxeLNFz7ndvezfBKbzcmrTzAdoixeddu4A9q pGmr2OLd0oR0bCchipRW5t9m6qWnGOJKSoFSR/LaSNj+9bcCCmAziLrOVRZ8Sf4uC+Bu e53Q== X-Gm-Message-State: AOAM532z1YCVI0KL8xzErBI37SlMv9fc9GZufVwGTDkCwITN9zm7/iTh dbyszYHMTTFLG2N7Imea7zXOmCMWxNRSNaC7dmYbF6Vg X-Google-Smtp-Source: ABdhPJz0Pt0psYREaz5GhuMS21n5We/1CfqmYgv9fuo64R0BNMnEBfjOZnwffpQgSNcFQIB8eGSbX1Lf7MCt/qp4rXY= X-Received: by 2002:a67:3015:: with SMTP id w21mr2359672vsw.99.1598030821256; Fri, 21 Aug 2020 10:27:01 -0700 (PDT) MIME-Version: 1.0 References: <16f28691ff66e8aeb280532cc146c8ee49d6cda4.1597994106.git.osandov@osandov.com> In-Reply-To: <16f28691ff66e8aeb280532cc146c8ee49d6cda4.1597994106.git.osandov@osandov.com> Reply-To: fdmanana@gmail.com From: Filipe Manana Date: Fri, 21 Aug 2020 18:26:50 +0100 Message-ID: Subject: Re: [PATCH 1/9] btrfs: send: get rid of i_size logic in send_write() To: Omar Sandoval Cc: linux-btrfs , linux-fsdevel Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, Aug 21, 2020 at 8:42 AM Omar Sandoval wrote: > > From: Omar Sandoval > > send_write()/fill_read_buf() have some logic for avoiding reading past > i_size. However, everywhere that we call > send_write()/send_extent_data(), we've already clamped the length down > to i_size. Get rid of the i_size handling, which simplifies the next > change. > > Signed-off-by: Omar Sandoval Reviewed-by: Filipe Manana Looks good, and it passed some long duration tests with both full and incremental sends here (with and without compression, no-holes, etc). Thanks. > --- > fs/btrfs/send.c | 37 ++++++++++--------------------------- > 1 file changed, 10 insertions(+), 27 deletions(-) > > diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c > index 7c7c09fc65e8..8af5e867e4ca 100644 > --- a/fs/btrfs/send.c > +++ b/fs/btrfs/send.c > @@ -4794,7 +4794,7 @@ static int process_all_new_xattrs(struct send_ctx *= sctx) > return ret; > } > > -static ssize_t fill_read_buf(struct send_ctx *sctx, u64 offset, u32 len) > +static int fill_read_buf(struct send_ctx *sctx, u64 offset, u32 len) > { > struct btrfs_root *root =3D sctx->send_root; > struct btrfs_fs_info *fs_info =3D root->fs_info; > @@ -4804,21 +4804,13 @@ static ssize_t fill_read_buf(struct send_ctx *sct= x, u64 offset, u32 len) > pgoff_t index =3D offset >> PAGE_SHIFT; > pgoff_t last_index; > unsigned pg_offset =3D offset_in_page(offset); > - ssize_t ret =3D 0; > + int ret =3D 0; > + size_t read =3D 0; > > inode =3D btrfs_iget(fs_info->sb, sctx->cur_ino, root); > if (IS_ERR(inode)) > return PTR_ERR(inode); > > - if (offset + len > i_size_read(inode)) { > - if (offset > i_size_read(inode)) > - len =3D 0; > - else > - len =3D offset - i_size_read(inode); > - } > - if (len =3D=3D 0) > - goto out; > - > last_index =3D (offset + len - 1) >> PAGE_SHIFT; > > /* initial readahead */ > @@ -4859,16 +4851,15 @@ static ssize_t fill_read_buf(struct send_ctx *sct= x, u64 offset, u32 len) > } > > addr =3D kmap(page); > - memcpy(sctx->read_buf + ret, addr + pg_offset, cur_len); > + memcpy(sctx->read_buf + read, addr + pg_offset, cur_len); > kunmap(page); > unlock_page(page); > put_page(page); > index++; > pg_offset =3D 0; > len -=3D cur_len; > - ret +=3D cur_len; > + read +=3D cur_len; > } > -out: > iput(inode); > return ret; > } > @@ -4882,7 +4873,6 @@ static int send_write(struct send_ctx *sctx, u64 of= fset, u32 len) > struct btrfs_fs_info *fs_info =3D sctx->send_root->fs_info; > int ret =3D 0; > struct fs_path *p; > - ssize_t num_read =3D 0; > > p =3D fs_path_alloc(); > if (!p) > @@ -4890,12 +4880,9 @@ static int send_write(struct send_ctx *sctx, u64 o= ffset, u32 len) > > btrfs_debug(fs_info, "send_write offset=3D%llu, len=3D%d", offset= , len); > > - num_read =3D fill_read_buf(sctx, offset, len); > - if (num_read <=3D 0) { > - if (num_read < 0) > - ret =3D num_read; > + ret =3D fill_read_buf(sctx, offset, len); > + if (ret < 0) > goto out; > - } > > ret =3D begin_cmd(sctx, BTRFS_SEND_C_WRITE); > if (ret < 0) > @@ -4907,16 +4894,14 @@ static int send_write(struct send_ctx *sctx, u64 = offset, u32 len) > > TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p); > TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset); > - TLV_PUT(sctx, BTRFS_SEND_A_DATA, sctx->read_buf, num_read); > + TLV_PUT(sctx, BTRFS_SEND_A_DATA, sctx->read_buf, len); > > ret =3D send_cmd(sctx); > > tlv_put_failure: > out: > fs_path_free(p); > - if (ret < 0) > - return ret; > - return num_read; > + return ret; > } > > /* > @@ -5095,9 +5080,7 @@ static int send_extent_data(struct send_ctx *sctx, > ret =3D send_write(sctx, offset + sent, size); > if (ret < 0) > return ret; > - if (!ret) > - break; > - sent +=3D ret; > + sent +=3D size; > } > return 0; > } > -- > 2.28.0 > --=20 Filipe David Manana, =E2=80=9CWhether you think you can, or you think you can't =E2=80=94 you're= right.=E2=80=9D