Commit bba3a87e authored by Takashi Iwai's avatar Takashi Iwai Committed by Greg Kroah-Hartman
Browse files

firmware: Introduce request_firmware_direct() 



When CONFIG_FW_LOADER_USER_HELPER is set, request_firmware() falls
back to the usermode helper for loading via udev when the direct
loading fails.  But the recent udev takes way too long timeout (60
seconds) for non-existing firmware.  This is unacceptable for the
drivers like microcode loader where they load firmwares optionally,
i.e. it's no error even if no requested file exists.

This patch provides a new helper function, request_firmware_direct().
It behaves as same as request_firmware() except for that it doesn't
fall back to usermode helper but returns an error immediately if the
f/w can't be loaded directly in kernel.

Without CONFIG_FW_LOADER_USER_HELPER=y, request_firmware_direct() is
just an alias of request_firmware(), due to obvious reason.

Tested-by: default avatarPrarit Bhargava <prarit@redhat.com>
Acked-by: default avatarMing Lei <ming.lei@canonical.com>
Acked-by: default avatarBorislav Petkov <bp@suse.de>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 020d30f1

drivers/base/firmware_class.c

+34 −7
Original line number Diff line number Diff line
@@ -1061,7 +1061,7 @@ static int assign_firmware_buf(struct firmware *fw, struct device *device, 
/* called from request_firmware() and request_firmware_work_func() */

static int

_request_firmware(const struct firmware **firmware_p, const char *name,

		  struct device *device, bool uevent, bool nowait)

		  struct device *device, bool uevent, bool nowait, bool fallback)

{

	struct firmware *fw;

	long timeout;
@@ -1095,12 +1095,15 @@ _request_firmware(const struct firmware **firmware_p, const char *name, 


	ret = fw_get_filesystem_firmware(device, fw->priv);

	if (ret) {

		dev_warn(device, "Direct firmware load failed with error %d\n",

		if (fallback) {

			dev_warn(device,

				 "Direct firmware load failed with error %d\n",

				 ret);

			dev_warn(device, "Falling back to user helper\n");

			ret = fw_load_from_user_helper(fw, name, device,

					       uevent, nowait, timeout);

		}

	}



	/* don't cache firmware handled without uevent */

	if (!ret)
@@ -1146,12 +1149,36 @@ request_firmware(const struct firmware **firmware_p, const char *name, 


	/* Need to pin this module until return */

	__module_get(THIS_MODULE);

	ret = _request_firmware(firmware_p, name, device, true, false);

	ret = _request_firmware(firmware_p, name, device, true, false, true);

	module_put(THIS_MODULE);

	return ret;

}

EXPORT_SYMBOL(request_firmware);



#ifdef CONFIG_FW_LOADER_USER_HELPER

/**

 * request_firmware: - load firmware directly without usermode helper

 * @firmware_p: pointer to firmware image

 * @name: name of firmware file

 * @device: device for which firmware is being loaded

 *

 * This function works pretty much like request_firmware(), but this doesn't

 * fall back to usermode helper even if the firmware couldn't be loaded

 * directly from fs.  Hence it's useful for loading optional firmwares, which

 * aren't always present, without extra long timeouts of udev.

 **/

int request_firmware_direct(const struct firmware **firmware_p,

			    const char *name, struct device *device)

{

	int ret;

	__module_get(THIS_MODULE);

	ret = _request_firmware(firmware_p, name, device, true, false, false);

	module_put(THIS_MODULE);

	return ret;

}

EXPORT_SYMBOL_GPL(request_firmware_direct);

#endif



/**

 * release_firmware: - release the resource associated with a firmware image

 * @fw: firmware resource to release
@@ -1185,7 +1212,7 @@ static void request_firmware_work_func(struct work_struct *work) 
	fw_work = container_of(work, struct firmware_work, work);



	_request_firmware(&fw, fw_work->name, fw_work->device,

			  fw_work->uevent, true);

			  fw_work->uevent, true, true);

	fw_work->cont(fw, fw_work->context);

	put_device(fw_work->device); /* taken in request_firmware_nowait() */

include/linux/firmware.h

+7 −0
Original line number Diff line number Diff line
@@ -68,4 +68,11 @@ static inline void release_firmware(const struct firmware *fw) 


#endif



#ifdef CONFIG_FW_LOADER_USER_HELPER

int request_firmware_direct(const struct firmware **fw, const char *name,

			    struct device *device);

#else

#define request_firmware_direct	request_firmware

#endif



#endif

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