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 26 struct buffer_head * 27 befs_bread_iaddr(struct super_block *sb, befs_inode_addr iaddr) 28 { 29 struct buffer_head *bh = NULL; 30 befs_blocknr_t block = 0; 31 struct befs_sb_info *befs_sb = BEFS_SB(sb); 32 33 befs_debug(sb, "---> Enter %s " 34 "[%u, %hu, %hu]", __func__, iaddr.allocation_group, 35 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, "%s: offset = %lu", __func__, (unsigned long)block); 46 47 bh = sb_bread(sb, block); 48 49 if (bh == NULL) { 50 befs_error(sb, "Failed to read block %lu", 51 (unsigned long)block); 52 goto error; 53 } 54 55 befs_debug(sb, "<--- %s", __func__); 56 return bh; 57 58 error: 59 befs_debug(sb, "<--- %s ERROR", __func__); 60 return NULL; 61 } 62 63 struct buffer_head * 64 befs_bread(struct super_block *sb, befs_blocknr_t block) 65 { 66 struct buffer_head *bh = NULL; 67 68 befs_debug(sb, "---> Enter %s %lu", __func__, (unsigned long)block); 69 70 bh = sb_bread(sb, block); 71 72 if (bh == NULL) { 73 befs_error(sb, "Failed to read block %lu", 74 (unsigned long)block); 75 goto error; 76 } 77 78 befs_debug(sb, "<--- %s", __func__); 79 80 return bh; 81 82 error: 83 befs_debug(sb, "<--- %s ERROR", __func__); 84 return NULL; 85 } 86