From 19fa5be1d92be3112521145bf99f77007abf6b16 Mon Sep 17 00:00:00 2001 From: Greg Price Date: Fri, 29 Nov 2013 15:50:06 -0500 Subject: [PATCH] random: fix comment on "account" This comment didn't quite keep up as extract_entropy() was split into four functions. Put each bit by the function it describes. Signed-off-by: Greg Price Signed-off-by: "Theodore Ts'o" --- drivers/char/random.c | 31 +++++++++++++++++++++---------- 1 file changed, 21 insertions(+), 10 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index fcc2bff8f887..2c532a6b0a21 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -958,17 +958,9 @@ static void push_to_pool(struct work_struct *work) } /* - * These functions extracts randomness from the "entropy pool", and - * returns it in a buffer. - * - * The min parameter specifies the minimum amount we can pull before - * failing to avoid races that defeat catastrophic reseeding while the - * reserved parameter indicates how much entropy we must leave in the - * pool after each pull to avoid starving other readers. - * - * Note: extract_entropy() assumes that .poolwords is a multiple of 16 words. + * This function decides how many bytes to actually take from the + * given pool, and also debits the entropy count accordingly. */ - static size_t account(struct entropy_store *r, size_t nbytes, int min, int reserved) { @@ -1018,6 +1010,12 @@ retry: return ibytes; } +/* + * This function does the actual extraction for extract_entropy and + * extract_entropy_user. + * + * Note: we assume that .poolwords is a multiple of 16 words. + */ static void extract_buf(struct entropy_store *r, __u8 *out) { int i; @@ -1079,6 +1077,15 @@ static void extract_buf(struct entropy_store *r, __u8 *out) memset(&hash, 0, sizeof(hash)); } +/* + * This function extracts randomness from the "entropy pool", and + * returns it in a buffer. + * + * The min parameter specifies the minimum amount we can pull before + * failing to avoid races that defeat catastrophic reseeding while the + * reserved parameter indicates how much entropy we must leave in the + * pool after each pull to avoid starving other readers. + */ static ssize_t extract_entropy(struct entropy_store *r, void *buf, size_t nbytes, int min, int reserved) { @@ -1129,6 +1136,10 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf, return ret; } +/* + * This function extracts randomness from the "entropy pool", and + * returns it in a userspace buffer. + */ static ssize_t extract_entropy_user(struct entropy_store *r, void __user *buf, size_t nbytes) { -- 2.20.1