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v7fs_io_user.c revision 1.1 
      1 /*	$NetBSD: v7fs_io_user.c,v 1.1 2011/06/27 11:52:25 uch 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 #include <sys/cdefs.h>
     33 #ifndef lint
     34 __RCSID("$NetBSD: v7fs_io_user.c,v 1.1 2011/06/27 11:52:25 uch Exp $");
     35 #endif /* not lint */
     36 
     37 #include <stdio.h>
     38 #include <stdlib.h>
     39 #include <string.h>
     40 #include <errno.h>
     41 #include <unistd.h>
     42 #include <err.h>
     43 #include <sys/mman.h>
     44 #include "v7fs.h"
     45 #include "v7fs_endian.h"
     46 #include "v7fs_impl.h"
     47 
     48 #ifdef V7FS_IO_DEBUG
     49 #define	DPRINTF(fmt, args...)	printf("%s: " fmt, __func__, ##args)
     50 #else
     51 #define	DPRINTF(fmt, args...)	((void)0)
     52 #endif
     53 
     54 struct local_io {
     55 	int fd;
     56 	size_t size;
     57 	size_t blksz;
     58 	uint8_t *addr;
     59 } local;
     60 
     61 static bool read_sector(void *, uint8_t *, daddr_t);
     62 static bool write_sector(void *, uint8_t *, daddr_t);
     63 static bool read_mmap(void *, uint8_t *, daddr_t);
     64 static bool write_mmap(void *, uint8_t *, daddr_t);
     65 
     66 int
     67 v7fs_io_init(struct v7fs_self **fs, const struct v7fs_mount_device *mount,
     68     size_t block_size)
     69 {
     70 	struct v7fs_self *p;
     71 
     72 	if (!(p = (struct v7fs_self *)malloc(sizeof(*p))))
     73 		return ENOMEM;
     74 	memset(p, 0, sizeof(*p));
     75 
     76 	/* Endian */
     77 	p->endian = mount->endian;
     78 #ifdef V7FS_EI
     79 	v7fs_endian_init(p);
     80 #endif
     81 	local.blksz = block_size;
     82 	local.fd = mount->device.fd;
     83 	local.size = mount->sectors * block_size;
     84 	local.addr = mmap(NULL, local.size, PROT_READ | PROT_WRITE | PROT_NONE,
     85 	    MAP_FILE | MAP_SHARED/*writeback*/, local.fd,  0);
     86 	if (local.addr == MAP_FAILED) {
     87 		warn("mmap failed. use direct I/O.");
     88 		local.addr = 0;
     89 		p->io.read = read_sector;
     90 		p->io.write = write_sector;
     91 	} else {
     92 		DPRINTF("mmaped addr=%p\n", local.addr);
     93 		p->io.read = read_mmap;
     94 		p->io.write = write_mmap;
     95 	}
     96 
     97 	p->io.cookie = &local;
     98 	*fs = p;
     99 
    100 	return 0;
    101 }
    102 
    103 void
    104 v7fs_io_fini(struct v7fs_self *fs)
    105 {
    106 	struct local_io *lio = (struct local_io *)fs->io.cookie;
    107 
    108 	if (lio->addr) {
    109 		if (munmap(lio->addr, lio->size) != 0)
    110 			warn(0);
    111 	}
    112 	fsync(lio->fd);
    113 
    114 	free(fs);
    115 }
    116 
    117 static bool
    118 read_sector(void *ctx, uint8_t *buf, daddr_t sector)
    119 {
    120 	struct local_io *lio = (struct local_io *)ctx;
    121 	size_t blksz = lio->blksz;
    122 	int fd = lio->fd;
    123 
    124 	if ((lseek(fd, sector * blksz, SEEK_SET) < 0) ||
    125 	    (read(fd, buf, blksz) < (ssize_t)blksz)) {
    126 		warn("sector=%ld\n", (long)sector);
    127 		return false;
    128 	}
    129 
    130 	return true;
    131 }
    132 
    133 static bool
    134 write_sector(void *ctx, uint8_t *buf, daddr_t sector)
    135 {
    136 	struct local_io *lio = (struct local_io *)ctx;
    137 	size_t blksz = lio->blksz;
    138 	int fd = lio->fd;
    139 
    140 	if ((lseek(fd, sector * blksz, SEEK_SET) < 0) ||
    141 	    (write(fd, buf, blksz) < (ssize_t)blksz)) {
    142 		warn("sector=%ld\n", (long)sector);
    143 		return false;
    144 	}
    145 
    146 	return true;
    147 }
    148 
    149 static bool
    150 read_mmap(void *ctx, uint8_t *buf, daddr_t sector)
    151 {
    152 	struct local_io *lio = (struct local_io *)ctx;
    153 	size_t blksz = lio->blksz;
    154 
    155 	memcpy(buf, lio->addr + sector * blksz, blksz);
    156 
    157 	return true;
    158 }
    159 
    160 static bool
    161 write_mmap(void *ctx, uint8_t *buf, daddr_t sector)
    162 {
    163 	struct local_io *lio = (struct local_io *)ctx;
    164 	size_t blksz = lio->blksz;
    165 
    166 	memcpy(lio->addr + sector * blksz, buf, blksz);
    167 
    168 	return true;
    169 }
    170