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Subject[PATCH 5/9] 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.

Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Price <price@mit.edu>
---
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 cf1357b..fe7ecdd 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -962,17 +962,9 @@ 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)
{
@@ -1022,6 +1014,12 @@ 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;
@@ -1083,6 +1081,15 @@ 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)
{
@@ -1133,6 +1140,10 @@ 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)
{
--
1.8.3.2


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