From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:53481 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965902AbbD1P6W (ORCPT ); Tue, 28 Apr 2015 11:58:22 -0400 From: Kalle Valo To: Andreas Fenkart Cc: linux-wireless@vger.kernel.org, Amitkumar Karwar , Avinash Patil Subject: Re: [PATCH 1/2] mwifiex: sdio: create global list of adapters References: <1428916704-9635-1-git-send-email-afenkart@gmail.com> Date: Tue, 28 Apr 2015 18:58:15 +0300 In-Reply-To: <1428916704-9635-1-git-send-email-afenkart@gmail.com> (Andreas Fenkart's message of "Mon, 13 Apr 2015 11:18:23 +0200") Message-ID: <87mw1s5joo.fsf@kamboji.qca.qualcomm.com> (sfid-20150428_175825_861454_85AA7C51) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-wireless-owner@vger.kernel.org List-ID: Andreas Fenkart writes: > we need to verify that a an adapter pointer, still points to a > valid adapter. this is not possible through other global structures, > such as net_namespace_list. the problem with the net_namespace_list > is that an adapter can have multiple interfaces, hence we had to > de-reference the maybe invalid pointer to get the interface struct. > > Signed-off-by: Andreas Fenkart > --- > drivers/net/wireless/mwifiex/sdio.c | 14 ++++++++++++++ > drivers/net/wireless/mwifiex/sdio.h | 1 + > 2 files changed, 15 insertions(+) > > diff --git a/drivers/net/wireless/mwifiex/sdio.c b/drivers/net/wireless/mwifiex/sdio.c > index 91e36cd..a70e114 100644 > --- a/drivers/net/wireless/mwifiex/sdio.c > +++ b/drivers/net/wireless/mwifiex/sdio.c > @@ -69,6 +69,12 @@ static struct memory_type_mapping mem_type_mapping_tbl[] = { > }; > > /* > + * list of active cards > + */ > +static LIST_HEAD(cards); > +static DEFINE_MUTEX(cards_mutex); > + > +/* > * SDIO probe. > * > * This function probes an mwifiex device and registers it. It allocates > @@ -130,6 +136,10 @@ mwifiex_sdio_probe(struct sdio_func *func, const struct sdio_device_id *id) > ret = -1; > } > > + mutex_lock(&cards_mutex); > + list_add(&card->next, &cards); > + mutex_unlock(&cards_mutex); > + > return ret; > } > > @@ -196,6 +206,10 @@ mwifiex_sdio_remove(struct sdio_func *func) > if (!card) > return; > > + mutex_lock(&cards_mutex); > + list_del(&card->next); > + mutex_unlock(&cards_mutex); This is extremely ugly and the commit log doesn't even tell anything about the issue you trying to fix so it's difficult to even suggest anything else. For starters can you provide more information, please? There has to be a better way to solve it. -- Kalle Valo