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-rw-r--r--sys/boot/common/bcache.c262
1 files changed, 0 insertions, 262 deletions
diff --git a/sys/boot/common/bcache.c b/sys/boot/common/bcache.c
deleted file mode 100644
index fc12f578f9fa6..0000000000000
--- a/sys/boot/common/bcache.c
+++ /dev/null
@@ -1,262 +0,0 @@
-/*-
- * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * $Id: bcache.c,v 1.3 1998/11/04 00:29:01 msmith Exp $
- */
-
-/*
- * Simple LRU block cache
- */
-
-#include <stand.h>
-#include <string.h>
-#include <bitstring.h>
-
-#include "bootstrap.h"
-
-/* #define BCACHE_DEBUG */
-
-#ifdef BCACHE_DEBUG
-#define BCACHE_TIMEOUT 10
-# define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __FUNCTION__ , ## args)
-#else
-#define BCACHE_TIMEOUT 2
-# define DEBUG(fmt, args...)
-#endif
-
-
-struct bcachectl
-{
- daddr_t bc_blkno;
- time_t bc_stamp;
- int bc_count;
-};
-
-static struct bcachectl *bcache_ctl;
-static caddr_t bcache_data;
-static bitstr_t *bcache_miss;
-static int bcache_nblks;
-static int bcache_blksize;
-static int bcache_hits, bcache_misses, bcache_ops, bcache_bypasses;
-static int bcache_bcount;
-
-static void bcache_insert(caddr_t buf, daddr_t blkno);
-static int bcache_lookup(caddr_t buf, daddr_t blkno);
-
-/*
- * Initialise the cache for (nblks) of (bsize).
- */
-int
-bcache_init(int nblks, size_t bsize)
-{
- int i;
-
- /* discard any old contents */
- if (bcache_data != NULL) {
- free(bcache_data);
- bcache_data = NULL;
- free(bcache_ctl);
- }
-
- /* Allocate control structures */
- bcache_nblks = nblks;
- bcache_blksize = bsize;
- bcache_data = malloc(bcache_nblks * bcache_blksize);
- bcache_ctl = (struct bcachectl *)malloc(bcache_nblks * sizeof(struct bcachectl));
- bcache_miss = bit_alloc((bcache_nblks + 1) / 2);
- if ((bcache_data == NULL) || (bcache_ctl == NULL) || (bcache_miss == NULL)) {
- if (bcache_miss)
- free(bcache_miss);
- if (bcache_ctl)
- free(bcache_ctl);
- if (bcache_data)
- free(bcache_data);
- bcache_data = NULL;
- return(ENOMEM);
- }
-
- /* Invalidate the cache */
- for (i = 0; i < bcache_nblks; i++) {
- bcache_ctl[i].bc_count = -1;
- bcache_ctl[i].bc_blkno = -1;
- }
-
- return(0);
-}
-
-/*
- * Handle a transfer request; fill in parts of the request that can
- * be satisfied by the cache, use the supplied strategy routine to do
- * device I/O and then use the I/O results to populate the cache.
- *
- * Requests larger than 1/2 the cache size will be bypassed and go
- * directly to the disk. XXX tune this.
- */
-int
-bcache_strategy(void *devdata, int rw, daddr_t blk, size_t size, void *buf, size_t *rsize)
-{
- struct bcache_devdata *dd = (struct bcache_devdata *)devdata;
- int nblk, p_size;
- daddr_t p_blk;
- caddr_t p_buf;
- int i, j, result;
-
- bcache_ops++;
-
- /* bypass large requests, or when the cache is inactive */
- if ((bcache_data == NULL) || ((size * 2 / bcache_blksize) > bcache_nblks)) {
- DEBUG("bypass %d from %d", size / bcache_blksize, blk);
- bcache_bypasses++;
- return(dd->dv_strategy(dd->dv_devdata, rw, blk, size, buf, rsize));
- }
-
- nblk = size / bcache_blksize;
- result = 0;
-
- /* Satisfy any cache hits up front */
- for (i = 0; i < nblk; i++) {
- if (bcache_lookup(buf + (bcache_blksize * i), blk + i)) {
- bit_set(bcache_miss, i); /* cache miss */
- bcache_misses++;
- } else {
- bit_clear(bcache_miss, i); /* cache hit */
- bcache_hits++;
- }
- }
-
- /* Go back and fill in any misses XXX optimise */
- p_blk = -1;
- p_buf = NULL;
- p_size = 0;
- for (i = 0; i < nblk; i++) {
- if (bit_test(bcache_miss, i)) {
- /* miss, add to pending transfer */
- if (p_blk == -1) {
- p_blk = blk + i;
- p_buf = buf + (bcache_blksize * i);
- p_size = 1;
- } else {
- p_size++;
- }
- } else if (p_blk != -1) {
- /* hit, complete pending transfer */
- result = dd->dv_strategy(dd->dv_devdata, rw, p_blk, p_size * bcache_blksize, p_buf, NULL);
- if (result != 0)
- goto done;
- for (j = 0; j < p_size; j++)
- bcache_insert(p_buf + (j * bcache_blksize), p_blk + j);
- p_blk = -1;
- }
- }
- if (p_blk != -1) {
- /* pending transfer left */
- result = dd->dv_strategy(dd->dv_devdata, rw, p_blk, p_size * bcache_blksize, p_buf, NULL);
- if (result != 0)
- goto done;
- for (j = 0; j < p_size; j++)
- bcache_insert(p_buf + (j * bcache_blksize), p_blk + j);
- }
-
- done:
- if ((result == 0) && (rsize != NULL))
- *rsize = size;
- return(result);
-}
-
-
-/*
- * Insert a block into the cache. Retire the oldest block to do so, if required.
- *
- * XXX the LRU algorithm will fail after 2^31 blocks have been transferred.
- */
-static void
-bcache_insert(caddr_t buf, daddr_t blkno)
-{
- time_t now;
- int i, cand, ocount;
-
- time(&now);
- cand = 0; /* assume the first block */
- ocount = bcache_ctl[0].bc_count;
-
- /* find the oldest block */
- for (i = 1; i < bcache_nblks; i++) {
- if (bcache_ctl[i].bc_blkno == blkno) {
- /* reuse old entry */
- cand = i;
- break;
- }
- if (bcache_ctl[i].bc_count < ocount) {
- ocount = bcache_ctl[i].bc_count;
- cand = i;
- }
- }
-
- DEBUG("insert blk %d -> %d @ %d # %d", blkno, cand, now, bcache_bcount);
- bcopy(buf, bcache_data + (bcache_blksize * cand), bcache_blksize);
- bcache_ctl[cand].bc_blkno = blkno;
- bcache_ctl[cand].bc_stamp = now;
- bcache_ctl[cand].bc_count = bcache_bcount++;
-}
-
-/*
- * Look for a block in the cache. Blocks more than BCACHE_TIMEOUT seconds old
- * may be stale (removable media) and thus are discarded. Copy the block out
- * if successful and return zero, or return nonzero on failure.
- */
-static int
-bcache_lookup(caddr_t buf, daddr_t blkno)
-{
- time_t now;
- int i;
-
- time(&now);
-
- for (i = 0; i < bcache_nblks; i++)
- /* cache hit? */
- if ((bcache_ctl[i].bc_blkno == blkno) && ((bcache_ctl[i].bc_stamp + BCACHE_TIMEOUT) >= now)) {
- bcopy(bcache_data + (bcache_blksize * i), buf, bcache_blksize);
- DEBUG("hit blk %d <- %d (now %d then %d)", blkno, i, now, bcache_ctl[i].bc_stamp);
- return(0);
- }
- return(ENOENT);
-}
-
-COMMAND_SET(bcachestat, "bcachestat", "get disk block cache stats", command_bcache);
-
-static int
-command_bcache(int argc, char *argv[])
-{
- int i;
-
- for (i = 0; i < bcache_nblks; i++) {
- printf("%08x %04x %04x|", bcache_ctl[i].bc_blkno, bcache_ctl[i].bc_stamp & 0xffff, bcache_ctl[i].bc_count & 0xffff);
- if (((i + 1) % 4) == 0)
- printf("\n");
- }
- printf("\n%d ops %d bypasses %d hits %d misses\n", bcache_ops, bcache_bypasses, bcache_hits, bcache_misses);
- return(CMD_OK);
-}
-
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