From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761548AbcLAWE2 (ORCPT ); Thu, 1 Dec 2016 17:04:28 -0500 Received: from mail.sigma-star.at ([95.130.255.111]:45998 "EHLO mail.sigma-star.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760101AbcLAWCh (ORCPT ); Thu, 1 Dec 2016 17:02:37 -0500 From: Richard Weinberger To: linux-mtd@lists.infradead.org Cc: david@sigma-star.at, tytso@mit.edu, dedekind1@gmail.com, adrian.hunter@intel.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, adilger.kernel@dilger.ca, akpm@linux-foundation.org, linux-ext4@vger.kernel.org, Richard Weinberger Subject: [PATCH 2/6] ubifs: Provide a custom llseek for directories Date: Thu, 1 Dec 2016 23:02:17 +0100 Message-Id: <1480629741-18375-3-git-send-email-richard@nod.at> X-Mailer: git-send-email 2.7.3 In-Reply-To: <1480629741-18375-1-git-send-email-richard@nod.at> References: <1480629741-18375-1-git-send-email-richard@nod.at> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When UBIFS is using 64bit cookies for directory offsets, we have to support seeking that deep into direcoties. Since generic_file_llseek() is uses sb->s_maxbytes it will fail for use because on ubifs sb->s_maxbytes is the real maxmal file size which can be much smaller than 64bit due to limitations of the flash device. Therefore provie a custom llseek operation. Signed-off-by: Richard Weinberger --- fs/ubifs/dir.c | 12 +++++++++++- fs/ubifs/ubifs-media.h | 6 ++++++ 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 7f01f3d2ac3b..883b2fdf51df 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -1721,6 +1721,16 @@ static int ubifs_dir_open(struct inode *dir, struct file *file) return 0; } +static loff_t ubifs_dir_llseek(struct file *file, loff_t offset, int whence) +{ + struct inode *inode = file->f_mapping->host; + + return generic_file_llseek_size(file, offset, whence, + (loff_t)UBIFS_S_KEY_HASH_MASK << + UBIFS_DH_BITS | UBIFS_DH_MASK, + i_size_read(inode)); +} + const struct inode_operations ubifs_dir_inode_operations = { .lookup = ubifs_lookup, .create = ubifs_create, @@ -1741,7 +1751,7 @@ const struct inode_operations ubifs_dir_inode_operations = { }; const struct file_operations ubifs_dir_operations = { - .llseek = generic_file_llseek, + .llseek = ubifs_dir_llseek, .release = ubifs_dir_release, .read = generic_read_dir, .iterate_shared = ubifs_readdir, diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h index e8c23c9d4f4a..5939776c7359 100644 --- a/fs/ubifs/ubifs-media.h +++ b/fs/ubifs/ubifs-media.h @@ -214,6 +214,12 @@ enum { #define UBIFS_S_KEY_HASH_MASK UBIFS_S_KEY_BLOCK_MASK /* + * We use 32 bits for the double hash cookie. + */ +#define UBIFS_DH_MASK 0xffffffff +#define UBIFS_DH_BITS 32 + +/* * Key types. * * UBIFS_INO_KEY: inode node key -- 2.7.3