From 7dcc01343e483efda0882456f8361f061a5f416d Mon Sep 17 00:00:00 2001 From: Andres Rodriguez Date: Thu, 10 May 2018 13:08:45 -0700 Subject: [PATCH] firmware: add firmware_request_nowarn() - load firmware without warnings Currently the firmware loader only exposes one silent path for querying optional firmware, and that is firmware_request_direct(). This function also disables the sysfs fallback mechanism, which might not always be the desired behaviour [0]. This patch introduces a variations of request_firmware() that enable the caller to disable the undesired warning messages but enables the sysfs fallback mechanism. This is equivalent to adding FW_OPT_NO_WARN to the old behaviour. [0]: https://git.kernel.org/linus/c0cc00f250e1 Signed-off-by: Andres Rodriguez Reviewed-by: Kees Cook Acked-by: Luis R. Rodriguez [mcgrof: used the old API calls as the full rename is not done yet, and add the caller for when FW_LOADER is disabled, enhance documentation ] Signed-off-by: Luis R. Rodriguez Signed-off-by: Greg Kroah-Hartman --- .../driver-api/firmware/request_firmware.rst | 5 ++++ drivers/base/firmware_loader/main.c | 27 +++++++++++++++++++ include/linux/firmware.h | 10 +++++++ 3 files changed, 42 insertions(+) diff --git a/Documentation/driver-api/firmware/request_firmware.rst b/Documentation/driver-api/firmware/request_firmware.rst index d5ec95a7195b..f62bdcbfed5b 100644 --- a/Documentation/driver-api/firmware/request_firmware.rst +++ b/Documentation/driver-api/firmware/request_firmware.rst @@ -20,6 +20,11 @@ request_firmware .. kernel-doc:: drivers/base/firmware_loader/main.c :functions: request_firmware +firmware_request_nowarn +----------------------- +.. kernel-doc:: drivers/base/firmware_loader/main.c + :functions: firmware_request_nowarn + request_firmware_direct ----------------------- .. kernel-doc:: drivers/base/firmware_loader/main.c diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index abdc4e4d55f1..0943e7065e0e 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -631,6 +631,33 @@ request_firmware(const struct firmware **firmware_p, const char *name, } EXPORT_SYMBOL(request_firmware); +/** + * firmware_request_nowarn() - request for an optional fw module + * @firmware: pointer to firmware image + * @name: name of firmware file + * @device: device for which firmware is being loaded + * + * This function is similar in behaviour to request_firmware(), except + * it doesn't produce warning messages when the file is not found. + * The sysfs fallback mechanism is enabled if direct filesystem lookup fails, + * however, however failures to find the firmware file with it are still + * suppressed. It is therefore up to the driver to check for the return value + * of this call and to decide when to inform the users of errors. + **/ +int firmware_request_nowarn(const struct firmware **firmware, const char *name, + struct device *device) +{ + int ret; + + /* Need to pin this module until return */ + __module_get(THIS_MODULE); + ret = _request_firmware(firmware, name, device, NULL, 0, + FW_OPT_UEVENT | FW_OPT_NO_WARN); + module_put(THIS_MODULE); + return ret; +} +EXPORT_SYMBOL_GPL(firmware_request_nowarn); + /** * request_firmware_direct() - load firmware directly without usermode helper * @firmware_p: pointer to firmware image diff --git a/include/linux/firmware.h b/include/linux/firmware.h index 41050417cafb..2dd566c91d44 100644 --- a/include/linux/firmware.h +++ b/include/linux/firmware.h @@ -42,6 +42,8 @@ struct builtin_fw { #if defined(CONFIG_FW_LOADER) || (defined(CONFIG_FW_LOADER_MODULE) && defined(MODULE)) int request_firmware(const struct firmware **fw, const char *name, struct device *device); +int firmware_request_nowarn(const struct firmware **fw, const char *name, + struct device *device); int request_firmware_nowait( struct module *module, bool uevent, const char *name, struct device *device, gfp_t gfp, void *context, @@ -59,6 +61,14 @@ static inline int request_firmware(const struct firmware **fw, { return -EINVAL; } + +static inline int firmware_request_nowarn(const struct firmware **fw, + const char *name, + struct device *device) +{ + return -EINVAL; +} + static inline int request_firmware_nowait( struct module *module, bool uevent, const char *name, struct device *device, gfp_t gfp, void *context,