linux_dsm_epyc7002/include/linux/hw_random.h
Torsten Duwe 0f734e6e76 hwrng: add per-device entropy derating
This patch introduces a derating factor to struct hwrng for
the random bits going into the kernel input pool, and a common
default derating for drivers which do not specify one.

Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
2014-07-15 04:49:40 -04:00

57 lines
1.8 KiB
C

/*
Hardware Random Number Generator
Please read Documentation/hw_random.txt for details on use.
----------------------------------------------------------
This software may be used and distributed according to the terms
of the GNU General Public License, incorporated herein by reference.
*/
#ifndef LINUX_HWRANDOM_H_
#define LINUX_HWRANDOM_H_
#include <linux/types.h>
#include <linux/list.h>
/**
* struct hwrng - Hardware Random Number Generator driver
* @name: Unique RNG name.
* @init: Initialization callback (can be NULL).
* @cleanup: Cleanup callback (can be NULL).
* @data_present: Callback to determine if data is available
* on the RNG. If NULL, it is assumed that
* there is always data available. *OBSOLETE*
* @data_read: Read data from the RNG device.
* Returns the number of lower random bytes in "data".
* Must not be NULL. *OBSOLETE*
* @read: New API. drivers can fill up to max bytes of data
* into the buffer. The buffer is aligned for any type.
* @priv: Private data, for use by the RNG driver.
* @quality: Estimation of true entropy in RNG's bitstream
* (per mill).
*/
struct hwrng {
const char *name;
int (*init)(struct hwrng *rng);
void (*cleanup)(struct hwrng *rng);
int (*data_present)(struct hwrng *rng, int wait);
int (*data_read)(struct hwrng *rng, u32 *data);
int (*read)(struct hwrng *rng, void *data, size_t max, bool wait);
unsigned long priv;
unsigned short quality;
/* internal. */
struct list_head list;
};
/** Register a new Hardware Random Number Generator driver. */
extern int hwrng_register(struct hwrng *rng);
/** Unregister a Hardware Random Number Generator driver. */
extern void hwrng_unregister(struct hwrng *rng);
/** Feed random bits into the pool. */
extern void add_hwgenerator_randomness(const char *buffer, size_t count, size_t entropy);
#endif /* LINUX_HWRANDOM_H_ */