diff options
Diffstat (limited to 'fs/befs/io.c')
-rw-r--r-- | fs/befs/io.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/fs/befs/io.c b/fs/befs/io.c new file mode 100644 index 00000000..ddef98aa --- /dev/null +++ b/fs/befs/io.c @@ -0,0 +1,83 @@ +/* + * linux/fs/befs/io.c + * + * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com + * + * Based on portions of file.c and inode.c + * by Makoto Kato (m_kato@ga2.so-net.ne.jp) + * + * Many thanks to Dominic Giampaolo, author of Practical File System + * Design with the Be File System, for such a helpful book. + * + */ + +#include <linux/buffer_head.h> + +#include "befs.h" +#include "io.h" + +/* + * Converts befs notion of disk addr to a disk offset and uses + * linux kernel function sb_bread() to get the buffer containing + * the offset. -Will Dyson + * + */ + +struct buffer_head * +befs_bread_iaddr(struct super_block *sb, befs_inode_addr iaddr) +{ + struct buffer_head *bh = NULL; + befs_blocknr_t block = 0; + befs_sb_info *befs_sb = BEFS_SB(sb); + + befs_debug(sb, "---> Enter befs_read_iaddr() " + "[%u, %hu, %hu]", + iaddr.allocation_group, iaddr.start, iaddr.len); + + if (iaddr.allocation_group > befs_sb->num_ags) { + befs_error(sb, "BEFS: Invalid allocation group %u, max is %u", + iaddr.allocation_group, befs_sb->num_ags); + goto error; + } + + block = iaddr2blockno(sb, &iaddr); + + befs_debug(sb, "befs_read_iaddr: offset = %lu", block); + + bh = sb_bread(sb, block); + + if (bh == NULL) { + befs_error(sb, "Failed to read block %lu", block); + goto error; + } + + befs_debug(sb, "<--- befs_read_iaddr()"); + return bh; + + error: + befs_debug(sb, "<--- befs_read_iaddr() ERROR"); + return NULL; +} + +struct buffer_head * +befs_bread(struct super_block *sb, befs_blocknr_t block) +{ + struct buffer_head *bh = NULL; + + befs_debug(sb, "---> Enter befs_read() %Lu", block); + + bh = sb_bread(sb, block); + + if (bh == NULL) { + befs_error(sb, "Failed to read block %lu", block); + goto error; + } + + befs_debug(sb, "<--- befs_read()"); + + return bh; + + error: + befs_debug(sb, "<--- befs_read() ERROR"); + return NULL; +} |