mirror of https://gitee.com/openkylin/linux.git
62 lines
1.4 KiB
C
62 lines
1.4 KiB
C
/*
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* linux/fs/befs/io.c
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*
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* Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
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*
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* Based on portions of file.c and inode.c
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* by Makoto Kato (m_kato@ga2.so-net.ne.jp)
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*
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* Many thanks to Dominic Giampaolo, author of Practical File System
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* Design with the Be File System, for such a helpful book.
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*
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*/
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#include <linux/buffer_head.h>
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#include "befs.h"
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#include "io.h"
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/*
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* Converts befs notion of disk addr to a disk offset and uses
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* linux kernel function sb_bread() to get the buffer containing
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* the offset. -Will Dyson
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*
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*/
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struct buffer_head *
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befs_bread_iaddr(struct super_block *sb, befs_inode_addr iaddr)
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{
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struct buffer_head *bh;
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befs_blocknr_t block;
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struct befs_sb_info *befs_sb = BEFS_SB(sb);
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befs_debug(sb, "---> Enter %s "
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"[%u, %hu, %hu]", __func__, iaddr.allocation_group,
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iaddr.start, iaddr.len);
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if (iaddr.allocation_group > befs_sb->num_ags) {
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befs_error(sb, "BEFS: Invalid allocation group %u, max is %u",
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iaddr.allocation_group, befs_sb->num_ags);
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goto error;
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}
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block = iaddr2blockno(sb, &iaddr);
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befs_debug(sb, "%s: offset = %lu", __func__, (unsigned long)block);
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bh = sb_bread(sb, block);
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if (bh == NULL) {
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befs_error(sb, "Failed to read block %lu",
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(unsigned long)block);
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goto error;
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}
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befs_debug(sb, "<--- %s", __func__);
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return bh;
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error:
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befs_debug(sb, "<--- %s ERROR", __func__);
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return NULL;
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}
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