From: jon ernst Subject: Re: [PATCH 10/31] libext2fs: Allow callers to punch a single block Date: Tue, 1 Oct 2013 15:09:44 -0400 Message-ID: References: <20131001012642.28415.89353.stgit@birch.djwong.org> <20131001012746.28415.15964.stgit@birch.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: "Theodore Ts'o" , linux-ext4@vger.kernel.org To: "Darrick J. Wong" Return-path: Received: from mail-oa0-f46.google.com ([209.85.219.46]:38655 "EHLO mail-oa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751251Ab3JATJp (ORCPT ); Tue, 1 Oct 2013 15:09:45 -0400 Received: by mail-oa0-f46.google.com with SMTP id k14so5207074oag.5 for ; Tue, 01 Oct 2013 12:09:44 -0700 (PDT) In-Reply-To: <20131001012746.28415.15964.stgit@birch.djwong.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Mon, Sep 30, 2013 at 9:27 PM, Darrick J. Wong wrote: > The range of blocks to punch is treated as an inclusive range on both ends, > i.e. if start=1 and end=2, both blocks 1 and 2 are punched out. Thus, start == > end means that the caller wishes to punch a single block. Remove the check > that prevents us from punching a single block. > > Signed-off-by: Darrick J. Wong > --- > lib/ext2fs/ext2fs.h | 4 ++++ > lib/ext2fs/punch.c | 5 +---- > 2 files changed, 5 insertions(+), 4 deletions(-) > > > diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h > index 311ceda..c37e00b 100644 > --- a/lib/ext2fs/ext2fs.h > +++ b/lib/ext2fs/ext2fs.h > @@ -1385,6 +1385,10 @@ extern errcode_t ext2fs_check_mount_point(const char *device, int *mount_flags, > char *mtpt, int mtlen); > > /* punch.c */ > +/* > + * NOTE: This function removes from an inode the blocks "start", "end", and > + * every block in between. > + */ > extern errcode_t ext2fs_punch(ext2_filsys fs, ext2_ino_t ino, > struct ext2_inode *inode, > char *block_buf, blk64_t start, > diff --git a/lib/ext2fs/punch.c b/lib/ext2fs/punch.c > index 11c7668..aac1942 100644 > --- a/lib/ext2fs/punch.c > +++ b/lib/ext2fs/punch.c > @@ -315,9 +315,6 @@ extern errcode_t ext2fs_punch(ext2_filsys fs, ext2_ino_t ino, > if (start > end) > return EINVAL; > > - if (start == end) > - return 0; > - > /* Read inode structure if necessary */ > if (!inode) { > retval = ext2fs_read_inode(fs, ino, &inode_buf); > @@ -332,7 +329,7 @@ extern errcode_t ext2fs_punch(ext2_filsys fs, ext2_ino_t ino, > > if (start > ~0U) > return 0; > - count = ((end - start) < ~0U) ? (end - start) : ~0U; > + count = ((end - start + 1) < ~0U) ? (end - start + 1) : ~0U; can you simply put "count = end - start + 1;" since you have checked start > end case earlier. > retval = ext2fs_punch_ind(fs, inode, block_buf, > (blk_t) start, count); > } > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html