1/* 2 * linux/fs/befs/io.c 3 * 4 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com 5 * 6 * Based on portions of file.c and inode.c 7 * by Makoto Kato (m_kato@ga2.so-net.ne.jp) 8 * 9 * Many thanks to Dominic Giampaolo, author of Practical File System 10 * Design with the Be File System, for such a helpful book. 11 * 12 */ 13 14#include <linux/buffer_head.h> 15 16#include "befs.h" 17#include "io.h" 18 19/* 20 * Converts befs notion of disk addr to a disk offset and uses 21 * linux kernel function sb_bread() to get the buffer containing 22 * the offset. -Will Dyson 23 * 24 */ 25 26struct buffer_head * 27befs_bread_iaddr(struct super_block *sb, befs_inode_addr iaddr) 28{ 29 struct buffer_head *bh = NULL; 30 befs_blocknr_t block = 0; 31 befs_sb_info *befs_sb = BEFS_SB(sb); 32 33 befs_debug(sb, "---> Enter befs_read_iaddr() " 34 "[%u, %hu, %hu]", 35 iaddr.allocation_group, iaddr.start, iaddr.len); 36 37 if (iaddr.allocation_group > befs_sb->num_ags) { 38 befs_error(sb, "BEFS: Invalid allocation group %u, max is %u", 39 iaddr.allocation_group, befs_sb->num_ags); 40 goto error; 41 } 42 43 block = iaddr2blockno(sb, &iaddr); 44 45 befs_debug(sb, "befs_read_iaddr: offset = %lu", block); 46 47 bh = sb_bread(sb, block); 48 49 if (bh == NULL) { 50 befs_error(sb, "Failed to read block %lu", block); 51 goto error; 52 } 53 54 befs_debug(sb, "<--- befs_read_iaddr()"); 55 return bh; 56 57 error: 58 befs_debug(sb, "<--- befs_read_iaddr() ERROR"); 59 return NULL; 60} 61 62struct buffer_head * 63befs_bread(struct super_block *sb, befs_blocknr_t block) 64{ 65 struct buffer_head *bh = NULL; 66 67 befs_debug(sb, "---> Enter befs_read() %Lu", block); 68 69 bh = sb_bread(sb, block); 70 71 if (bh == NULL) { 72 befs_error(sb, "Failed to read block %lu", block); 73 goto error; 74 } 75 76 befs_debug(sb, "<--- befs_read()"); 77 78 return bh; 79 80 error: 81 befs_debug(sb, "<--- befs_read() ERROR"); 82 return NULL; 83} 84