Files
kernel_google_b1c1/include/linux/random.h
Linus Torvalds 82461648c6 random32: move the pseudo-random 32-bit definitions to prandom.h
commit c0842fbc1b18c7a044e6ff3e8fa78bfa822c7d1a upstream.

The addition of percpu.h to the list of includes in random.h revealed
some circular dependencies on arm64 and possibly other platforms.  This
include was added solely for the pseudo-random definitions, which have
nothing to do with the rest of the definitions in this file but are
still there for legacy reasons.

This patch moves the pseudo-random parts to linux/prandom.h and the
percpu.h include with it, which is now guarded by _LINUX_PRANDOM_H and
protected against recursive inclusion.

A further cleanup step would be to remove this from <linux/random.h>
entirely, and make people who use the prandom infrastructure include
just the new header file.  That's a bit of a churn patch, but grepping
for "prandom_" and "next_pseudo_random32" "struct rnd_state" should
catch most users.

But it turns out that that nice cleanup step is fairly painful, because
a _lot_ of code currently seems to depend on the implicit include of
<linux/random.h>, which can currently come in a lot of ways, including
such fairly core headfers as <linux/net.h>.

So the "nice cleanup" part may or may never happen.

Fixes: 1c9df907da83 ("random: fix circular include dependency on arm64 after addition of percpu.h")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 11:01:52 +02:00

86 lines
2.0 KiB
C

/*
* include/linux/random.h
*
* Include file for the random number generator.
*/
#ifndef _LINUX_RANDOM_H
#define _LINUX_RANDOM_H
#include <linux/list.h>
#include <linux/once.h>
#include <uapi/linux/random.h>
struct random_ready_callback {
struct list_head list;
void (*func)(struct random_ready_callback *rdy);
struct module *owner;
};
extern void add_device_randomness(const void *, unsigned int);
#if defined(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) && !defined(__CHECKER__)
static inline void add_latent_entropy(void)
{
add_device_randomness((const void *)&latent_entropy,
sizeof(latent_entropy));
}
#else
static inline void add_latent_entropy(void) {}
#endif
extern void add_input_randomness(unsigned int type, unsigned int code,
unsigned int value) __latent_entropy;
extern void add_interrupt_randomness(int irq, int irq_flags) __latent_entropy;
extern void get_random_bytes(void *buf, int nbytes);
extern int add_random_ready_callback(struct random_ready_callback *rdy);
extern void del_random_ready_callback(struct random_ready_callback *rdy);
extern void get_random_bytes_arch(void *buf, int nbytes);
#ifndef MODULE
extern const struct file_operations random_fops, urandom_fops;
#endif
unsigned int get_random_int(void);
unsigned long get_random_long(void);
unsigned long randomize_page(unsigned long start, unsigned long range);
/*
* This is designed to be standalone for just prandom
* users, but for now we include it from <linux/random.h>
* for legacy reasons.
*/
#include <linux/prandom.h>
#ifdef CONFIG_ARCH_RANDOM
# include <asm/archrandom.h>
#else
static inline bool arch_get_random_long(unsigned long *v)
{
return 0;
}
static inline bool arch_get_random_int(unsigned int *v)
{
return 0;
}
static inline bool arch_has_random(void)
{
return 0;
}
static inline bool arch_get_random_seed_long(unsigned long *v)
{
return 0;
}
static inline bool arch_get_random_seed_int(unsigned int *v)
{
return 0;
}
static inline bool arch_has_random_seed(void)
{
return 0;
}
#endif
#endif /* _LINUX_RANDOM_H */