Home | History | Annotate | Line # | Download | only in v7fs 
      1 /*	$NetBSD: v7fs_io.c,v 1.3 2013/06/28 14:49:14 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2011 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by UCHIYAMA Yasushi.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #if HAVE_NBTOOL_CONFIG_H
     33 #include "nbtool_config.h"
     34 #endif
     35 
     36 #include <sys/cdefs.h>
     37 __KERNEL_RCSID(0, "$NetBSD: v7fs_io.c,v 1.3 2013/06/28 14:49:14 christos Exp $");
     38 #if defined _KERNEL_OPT
     39 #include "opt_v7fs.h"
     40 #endif
     41 
     42 #ifdef _KERNEL
     43 #include <sys/param.h>
     44 #else
     45 #include <stdio.h>
     46 #include <errno.h>
     47 #include <stdlib.h>
     48 #endif
     49 
     50 #include "v7fs.h"
     51 #include "v7fs_impl.h"
     52 
     53 #if defined _KERNEL
     54 #define	STATIC_BUFFER
     55 #endif
     56 
     57 #ifdef V7FS_IO_DEBUG
     58 #define	DPRINTF(fmt, args...)	printf("%s: " fmt, __func__, ##args)
     59 #else
     60 #define	DPRINTF(fmt, args...)	((void)0)
     61 #endif
     62 
     63 void *
     64 scratch_read(struct v7fs_self *fs, daddr_t blk)
     65 {
     66 #ifdef STATIC_BUFFER
     67 	int i;
     68 	MEM_LOCK(fs);
     69 	for (i = 0; i < V7FS_SELF_NSCRATCH; i++) {
     70 		if (fs->scratch_free & (1 << i)) {
     71 			fs->scratch_free &= ~(1 << i);
     72 			break;
     73 		}
     74 	}
     75 	if (i == V7FS_SELF_NSCRATCH) {
     76 		DPRINTF("No scratch area. increase V7FS_SELF_NSCRATCH\n");
     77 		assert(0);
     78 		MEM_UNLOCK(fs);
     79 		return NULL;
     80 	}
     81 
     82 	if (!fs->io.read(fs->io.cookie, fs->scratch[i], blk)) {
     83 		DPRINTF("*** I/O error block %ld\n", (long)blk);
     84 		fs->scratch_free |= (1 << i);
     85 		MEM_UNLOCK(fs);
     86 		return NULL;
     87 	}
     88 	MEM_UNLOCK(fs);
     89 	/* Statistic */
     90 	int n;
     91 	if ((n = scratch_remain(fs)) < fs->scratch_remain)
     92 		fs->scratch_remain = n;
     93 
     94 	return fs->scratch[i];
     95 #else
     96 	uint8_t *buf = malloc(V7FS_BSIZE);
     97 	if (!fs->io.read(fs->io.cookie, buf, blk)) {
     98 		DPRINTF("*** I/O error block %ld\n",(long)blk);
     99 		free(buf);
    100 		return NULL;
    101 	}
    102 	return buf;
    103 #endif
    104 }
    105 
    106 int
    107 scratch_remain(const struct v7fs_self *fs)
    108 {
    109 #ifdef STATIC_BUFFER
    110 	int nfree;
    111 	int i;
    112 	MEM_LOCK(fs);
    113 	for (i = 0, nfree = 0; i < V7FS_SELF_NSCRATCH; i++) {
    114 		if (fs->scratch_free & (1 << i)) {
    115 			nfree++;
    116 		}
    117 	}
    118 	MEM_UNLOCK(fs);
    119 	return nfree;
    120 #else
    121 	return -1;
    122 #endif
    123 }
    124 
    125 void
    126 scratch_free(struct v7fs_self *fs __unused, void *p)
    127 {
    128 #ifdef STATIC_BUFFER
    129 	int i;
    130 	MEM_LOCK(fs);
    131 	for (i = 0; i < V7FS_SELF_NSCRATCH; i++)
    132 		if (fs->scratch[i] == p) {
    133 			fs->scratch_free |= (1 << i);
    134 			break;
    135 		}
    136 	MEM_UNLOCK(fs);
    137 	assert(i != V7FS_SELF_NSCRATCH);
    138 #else
    139 	free(p);
    140 #endif
    141 }
    142