linux/drivers/base/firmware_loader/fallback.h
Luis R. Rodriguez ceb1813224 firmware: enable run time change of forcing fallback loader
Currently one requires to test four kernel configurations to test the
firmware API completely:

0)
  CONFIG_FW_LOADER=y

1)
  o CONFIG_FW_LOADER=y
  o CONFIG_FW_LOADER_USER_HELPER=y

2)
  o CONFIG_FW_LOADER=y
  o CONFIG_FW_LOADER_USER_HELPER=y
  o CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y

3) When CONFIG_FW_LOADER=m the built-in stuff is disabled, we have
   no current tests for this.

We can reduce the requirements to three kernel configurations by making
fw_config.force_sysfs_fallback a proc knob we flip on off. For kernels that
disable CONFIG_IKCONFIG_PROC this can also enable one to inspect if
CONFIG_FW_LOADER_USER_HELPER_FALLBACK was enabled at build time by checking
the proc value at boot time.

Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-20 09:28:47 +01:00

64 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __FIRMWARE_FALLBACK_H
#define __FIRMWARE_FALLBACK_H
#include <linux/firmware.h>
#include <linux/device.h>
/**
* struct firmware_fallback_config - firmware fallback configuratioon settings
*
* Helps describe and fine tune the fallback mechanism.
*
* @force_sysfs_fallback: force the sysfs fallback mechanism to be used
* as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y.
* Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
* functionality on a kernel where that config entry has been disabled.
* @old_timeout: for internal use
* @loading_timeout: the timeout to wait for the fallback mechanism before
* giving up, in seconds.
*/
struct firmware_fallback_config {
unsigned int force_sysfs_fallback;
int old_timeout;
int loading_timeout;
};
#ifdef CONFIG_FW_LOADER_USER_HELPER
int fw_sysfs_fallback(struct firmware *fw, const char *name,
struct device *device,
unsigned int opt_flags,
int ret);
void kill_pending_fw_fallback_reqs(bool only_kill_custom);
void fw_fallback_set_cache_timeout(void);
void fw_fallback_set_default_timeout(void);
int register_sysfs_loader(void);
void unregister_sysfs_loader(void);
#else /* CONFIG_FW_LOADER_USER_HELPER */
static inline int fw_sysfs_fallback(struct firmware *fw, const char *name,
struct device *device,
unsigned int opt_flags,
int ret)
{
/* Keep carrying over the same error */
return ret;
}
static inline void kill_pending_fw_fallback_reqs(bool only_kill_custom) { }
static inline void fw_fallback_set_cache_timeout(void) { }
static inline void fw_fallback_set_default_timeout(void) { }
static inline int register_sysfs_loader(void)
{
return 0;
}
static inline void unregister_sysfs_loader(void)
{
}
#endif /* CONFIG_FW_LOADER_USER_HELPER */
#endif /* __FIRMWARE_FALLBACK_H */