Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751856AbaJZP77 (ORCPT ); Sun, 26 Oct 2014 11:59:59 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:45038 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751533AbaJZP75 (ORCPT ); Sun, 26 Oct 2014 11:59:57 -0400 MIME-Version: 1.0 In-Reply-To: <1414131502-13886-2-git-send-email-hock.leong.kweh@intel.com> References: <1414131502-13886-1-git-send-email-hock.leong.kweh@intel.com> <1414131502-13886-2-git-send-email-hock.leong.kweh@intel.com> Date: Sun, 26 Oct 2014 23:59:55 +0800 Message-ID: Subject: Re: [PATCH v1 1/3] firmware loader: Introduce new API - request_firmware_abort() From: Ming Lei To: Kweh Hock Leong Cc: Matt Fleming , Sam Protsenko , Greg Kroah-Hartman , LKML , linux-efi@vger.kernel.org, Ong Boon Leong Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 24, 2014 at 2:18 PM, Kweh Hock Leong wrote: > From: "Kweh, Hock Leong" > > Besides aborting through user helper interface, a new API > request_firmware_abort() allows kernel driver module to abort the > request_firmware() / request_firmware_nowait() when they are no > longer needed. It is useful for cancelling an outstanding firmware > load if initiated from inside a module where that module is in the > process of being unloaded, since the unload function may not have > a handle to the struct firmware_buf. > > Note for people who use request_firmware_nowait(): > You are required to do your own synchronization after you call > request_firmware_abort() in order to continue unloading the > module. The example synchronization code shows below: > > while (THIS_MODULE && module_refcount(THIS_MODULE)) > msleep(20); > > Cc: Matt Fleming > Signed-off-by: Kweh, Hock Leong > --- > drivers/base/firmware_class.c | 30 ++++++++++++++++++++++++++++++ > include/linux/firmware.h | 4 ++++ > 2 files changed, 34 insertions(+) > > diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c > index d276e33..b2fe40b 100644 > --- a/drivers/base/firmware_class.c > +++ b/drivers/base/firmware_class.c > @@ -1291,6 +1291,36 @@ request_firmware_nowait( > } > EXPORT_SYMBOL(request_firmware_nowait); > > +/** > + * request_firmware_abort - abort the waiting of firmware request > + * @fw_name: name of firmware file > + * > + * @fw_name is the same name string while calling to request_firmware() > + * or request_firmware_nowait(). > + **/ > +int request_firmware_abort(const char *fw_name) > +{ > + struct firmware_buf *buf; > + struct firmware_buf *entry; > + > + spin_lock(&fw_cache.lock); > + buf = __fw_lookup_buf(fw_name); > + spin_unlock(&fw_cache.lock); You can call fw_lookup_buf() directly, otherwise feel free to add: Acked-by: Ming Lei > + if (!buf) > + return -ENOENT; > + > + mutex_lock(&fw_lock); > + list_for_each_entry(entry, &pending_fw_head, pending_list) { > + if (entry == buf) { > + __fw_load_abort(buf); > + break; > + } > + } > + mutex_unlock(&fw_lock); > + return 0; > +} > +EXPORT_SYMBOL(request_firmware_abort); > + > #ifdef CONFIG_PM_SLEEP > static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain); > > diff --git a/include/linux/firmware.h b/include/linux/firmware.h > index 5952933..ed90c8b 100644 > --- a/include/linux/firmware.h > +++ b/include/linux/firmware.h > @@ -47,6 +47,7 @@ int request_firmware_nowait( > void (*cont)(const struct firmware *fw, void *context)); > > void release_firmware(const struct firmware *fw); > +int request_firmware_abort(const char *fw_name); > #else > static inline int request_firmware(const struct firmware **fw, > const char *name, > @@ -66,6 +67,9 @@ static inline void release_firmware(const struct firmware *fw) > { > } > > +static inline int request_firmware_abort(const char *fw_name) > +{ > +} > #endif > > #ifdef CONFIG_FW_LOADER_USER_HELPER > -- > 1.7.9.5 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/