From: Matt Mackall <mpm@selenic.com>
Move the limit flag to the pool struct, begin process of eliminating extract
flags.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/char/random.c | 26 +++++++++-----------------
1 files changed, 9 insertions(+), 17 deletions(-)
diff -puN drivers/char/random.c~random-pt3-reservation-flag-in-pool-struct drivers/char/random.c
--- 25/drivers/char/random.c~random-pt3-reservation-flag-in-pool-struct 2005-01-26 17:39:35.404477944 -0800
+++ 25-akpm/drivers/char/random.c 2005-01-26 17:39:35.410477032 -0800
@@ -411,6 +411,7 @@ struct entropy_store {
struct poolinfo *poolinfo;
__u32 *pool;
const char *name;
+ int limit;
/* read-write data: */
spinlock_t lock ____cacheline_aligned_in_smp;
@@ -426,6 +427,7 @@ static __u32 nonblocking_pool_data[OUTPU
static struct entropy_store input_pool = {
.poolinfo = &poolinfo_table[0],
.name = "input",
+ .limit = 1,
.lock = SPIN_LOCK_UNLOCKED,
.pool = input_pool_data
};
@@ -433,6 +435,7 @@ static struct entropy_store input_pool =
static struct entropy_store blocking_pool = {
.poolinfo = &poolinfo_table[1],
.name = "blocking",
+ .limit = 1,
.lock = SPIN_LOCK_UNLOCKED,
.pool = blocking_pool_data
};
@@ -1178,7 +1181,6 @@ static void MD5Transform(__u32 buf[HASH_
#define EXTRACT_ENTROPY_USER 1
#define EXTRACT_ENTROPY_SECONDARY 2
-#define EXTRACT_ENTROPY_LIMIT 4
#define TMP_BUF_SIZE (HASH_BUFFER_SIZE + HASH_EXTRA_SIZE)
#define SEC_XFER_SIZE (TMP_BUF_SIZE*4)
@@ -1197,14 +1199,14 @@ static inline void xfer_secondary_pool(s
r->entropy_count < r->poolinfo->POOLBITS) {
int bytes = max_t(int, random_read_wakeup_thresh / 8,
min_t(int, nbytes, TMP_BUF_SIZE));
+ int rsvd = r->limit ? 0 : random_read_wakeup_thresh/4;
DEBUG_ENT("going to reseed %s with %d bits "
"(%d of %d requested)\n",
r->name, bytes * 8, nbytes * 8, r->entropy_count);
bytes=extract_entropy(&input_pool, tmp, bytes,
- random_read_wakeup_thresh / 8, 0,
- EXTRACT_ENTROPY_LIMIT);
+ random_read_wakeup_thresh / 8, rsvd, 0);
add_entropy_words(r, tmp, (bytes + 3) / 4);
credit_entropy_store(r, bytes*8);
}
@@ -1254,8 +1256,7 @@ static ssize_t extract_entropy(struct en
nbytes = 0;
} else {
/* If limited, never pull more than available */
- if (flags & EXTRACT_ENTROPY_LIMIT &&
- nbytes + reserved >= r->entropy_count / 8)
+ if (r->limit && nbytes + reserved >= r->entropy_count / 8)
nbytes = r->entropy_count/8 - reserved;
if(r->entropy_count / 8 >= nbytes + reserved)
@@ -1268,8 +1269,7 @@ static ssize_t extract_entropy(struct en
}
DEBUG_ENT("debiting %d entropy credits from %s%s\n",
- nbytes * 8, r->name,
- flags & EXTRACT_ENTROPY_LIMIT ? "" : " (unlimited)");
+ nbytes * 8, r->name, r->limit ? "" : " (unlimited)");
spin_unlock_irqrestore(&r->lock, cpuflags);
@@ -1450,7 +1450,6 @@ random_read(struct file * file, char __u
n = extract_entropy(&blocking_pool, buf, n, 0, 0,
EXTRACT_ENTROPY_USER |
- EXTRACT_ENTROPY_LIMIT |
EXTRACT_ENTROPY_SECONDARY);
DEBUG_ENT("read got %d bits (%d still needed)\n",
@@ -1502,15 +1501,8 @@ static ssize_t
urandom_read(struct file * file, char __user * buf,
size_t nbytes, loff_t *ppos)
{
- int flags = EXTRACT_ENTROPY_USER;
- unsigned long cpuflags;
-
- spin_lock_irqsave(&input_pool.lock, cpuflags);
- if (input_pool.entropy_count > input_pool.poolinfo->POOLBITS)
- flags |= EXTRACT_ENTROPY_SECONDARY;
- spin_unlock_irqrestore(&input_pool.lock, cpuflags);
-
- return extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0, flags);
+ return extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0,
+ EXTRACT_ENTROPY_USER);
}
static unsigned int
_