From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1eD3K8-0006qs-NY for barebox@lists.infradead.org; Fri, 10 Nov 2017 07:02:02 +0000 Date: Fri, 10 Nov 2017 08:01:34 +0100 From: Sascha Hauer Message-ID: <20171110070134.j2ydxid2j22nakvt@pengutronix.de> References: <20171108180747.16208-1-m.grzeschik@pengutronix.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20171108180747.16208-1-m.grzeschik@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH v2] uimage: fix: add can_lseek_backward and use in uimage_open To: Michael Grzeschik Cc: barebox@lists.infradead.org On Wed, Nov 08, 2017 at 07:07:47PM +0100, Michael Grzeschik wrote: > Since commit ce0cc7fe we support forward seek on tftpfs. This feature > breaks the condition to check rather we open an uimage over tftp. Since > backward seeking is the problem here, we add the function > can_lseek_backward and check for it instead of the simple lseek. > > Signed-off-by: Michael Grzeschik > --- > v1 -> v2: - added can_lseek_backward > - also fixed check in uimagefs > - aligned comments to check > > common/uimage.c | 4 ++-- > fs/uimagefs.c | 4 ++-- > include/fs.h | 20 ++++++++++++++++++++ > 3 files changed, 24 insertions(+), 4 deletions(-) Applied, thanks Sascha > > diff --git a/common/uimage.c b/common/uimage.c > index 28a25bba2d..b6f0f109ca 100644 > --- a/common/uimage.c > +++ b/common/uimage.c > @@ -111,9 +111,9 @@ again: > /* > * Hack around tftp fs. We need lseek for uImage support, but > * this cannot be implemented in tftp fs, so we detect this > - * by doing a test lseek and copy the file to ram if it fails > + * and copy the file to ram if it fails > */ > - if (IS_BUILTIN(CONFIG_FS_TFTP) && lseek(fd, 0, SEEK_SET)) { > + if (IS_BUILTIN(CONFIG_FS_TFTP) && !can_lseek_backward(fd)) { > close(fd); > ret = copy_file(filename, uimage_tmp, 0); > if (ret) > diff --git a/fs/uimagefs.c b/fs/uimagefs.c > index 13c1fbac05..c0c5750c2c 100644 > --- a/fs/uimagefs.c > +++ b/fs/uimagefs.c > @@ -374,9 +374,9 @@ again: > /* > * Hack around tftp fs. We need lseek for uImage support, but > * this cannot be implemented in tftp fs, so we detect this > - * by doing a test lseek and copy the file to ram if it fails > + * and copy the file to ram if it fails > */ > - if (IS_BUILTIN(CONFIG_FS_TFTP) && lseek(fd, 0, SEEK_SET)) { > + if (IS_BUILTIN(CONFIG_FS_TFTP) && !can_lseek_backward(fd)) { > close(fd); > ret = copy_file(priv->filename, priv->tmp, 0); > if (ret) > diff --git a/include/fs.h b/include/fs.h > index d7fa7714b4..f8a3b8bda4 100644 > --- a/include/fs.h > +++ b/include/fs.h > @@ -100,6 +100,26 @@ struct fs_device_d { > char *linux_rootarg; > }; > > +/* > + * Some filesystems i.e. tftpfs only support lseek into one direction. > + * To detect this limited functionality we add this extra function. > + * Additionaly we also return 0 if we even can not seek forward. > + */ > +static inline int can_lseek_backward(int fd) > +{ > + int ret; > + > + ret = lseek(fd, 1, SEEK_SET); > + if (ret < 0) > + return 0; > + > + ret = lseek(fd, 0, SEEK_SET); > + if (ret < 0) > + return 0; > + > + return ret; > +} > + > #define drv_to_fs_driver(d) container_of(d, struct fs_driver_d, drv) > > int flush(int fd); > -- > 2.11.0 > > > _______________________________________________ > barebox mailing list > barebox@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/barebox > -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox