summaryrefslogtreecommitdiff
path: root/drivers/char/random.c
diff options
context:
space:
mode:
authorJason A. Donenfeld <Jason@zx2c4.com>2017-01-22 16:34:08 +0100
committerTheodore Ts'o <tytso@mit.edu>2017-01-27 14:25:06 -0500
commitc440408cf6901eeb2c09563397e24a9097907078 (patch)
tree0b6333b3529b2d1608649fdbb2fa9217cdb020d7 /drivers/char/random.c
parentf5b98461cb8167ba362ad9f74c41d126b7becea7 (diff)
random: convert get_random_int/long into get_random_u32/u64
Many times, when a user wants a random number, he wants a random number of a guaranteed size. So, thinking of get_random_int and get_random_long in terms of get_random_u32 and get_random_u64 makes it much easier to achieve this. It also makes the code simpler. On 32-bit platforms, get_random_int and get_random_long are both aliased to get_random_u32. On 64-bit platforms, int->u32 and long->u64. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'drivers/char/random.c')
-rw-r--r--drivers/char/random.c55
1 files changed, 27 insertions, 28 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c
index b800e5479b7d..066ae125f2c8 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -2018,8 +2018,8 @@ struct ctl_table random_table[] = {
struct batched_entropy {
union {
- unsigned long entropy_long[CHACHA20_BLOCK_SIZE / sizeof(unsigned long)];
- unsigned int entropy_int[CHACHA20_BLOCK_SIZE / sizeof(unsigned int)];
+ u64 entropy_u64[CHACHA20_BLOCK_SIZE / sizeof(u64)];
+ u32 entropy_u32[CHACHA20_BLOCK_SIZE / sizeof(u32)];
};
unsigned int position;
};
@@ -2029,52 +2029,51 @@ struct batched_entropy {
* number is either as good as RDRAND or as good as /dev/urandom, with the
* goal of being quite fast and not depleting entropy.
*/
-static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_long);
-unsigned long get_random_long(void)
+static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_u64);
+u64 get_random_u64(void)
{
- unsigned long ret;
+ u64 ret;
struct batched_entropy *batch;
- if (arch_get_random_long(&ret))
+#if BITS_PER_LONG == 64
+ if (arch_get_random_long((unsigned long *)&ret))
return ret;
+#else
+ if (arch_get_random_long((unsigned long *)&ret) &&
+ arch_get_random_long((unsigned long *)&ret + 1))
+ return ret;
+#endif
- batch = &get_cpu_var(batched_entropy_long);
- if (batch->position % ARRAY_SIZE(batch->entropy_long) == 0) {
- extract_crng((u8 *)batch->entropy_long);
+ batch = &get_cpu_var(batched_entropy_u64);
+ if (batch->position % ARRAY_SIZE(batch->entropy_u64) == 0) {
+ extract_crng((u8 *)batch->entropy_u64);
batch->position = 0;
}
- ret = batch->entropy_long[batch->position++];
- put_cpu_var(batched_entropy_long);
+ ret = batch->entropy_u64[batch->position++];
+ put_cpu_var(batched_entropy_u64);
return ret;
}
-EXPORT_SYMBOL(get_random_long);
+EXPORT_SYMBOL(get_random_u64);
-#if BITS_PER_LONG == 32
-unsigned int get_random_int(void)
-{
- return get_random_long();
-}
-#else
-static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_int);
-unsigned int get_random_int(void)
+static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_u32);
+u32 get_random_u32(void)
{
- unsigned int ret;
+ u32 ret;
struct batched_entropy *batch;
if (arch_get_random_int(&ret))
return ret;
- batch = &get_cpu_var(batched_entropy_int);
- if (batch->position % ARRAY_SIZE(batch->entropy_int) == 0) {
- extract_crng((u8 *)batch->entropy_int);
+ batch = &get_cpu_var(batched_entropy_u32);
+ if (batch->position % ARRAY_SIZE(batch->entropy_u32) == 0) {
+ extract_crng((u8 *)batch->entropy_u32);
batch->position = 0;
}
- ret = batch->entropy_int[batch->position++];
- put_cpu_var(batched_entropy_int);
+ ret = batch->entropy_u32[batch->position++];
+ put_cpu_var(batched_entropy_u32);
return ret;
}
-#endif
-EXPORT_SYMBOL(get_random_int);
+EXPORT_SYMBOL(get_random_u32);
/**
* randomize_page - Generate a random, page aligned address