mirror of https://gitee.com/openkylin/linux.git
76 lines
1.7 KiB
C
76 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/buffer_head.h>
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#include "minix.h"
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enum {DIRECT = 7, DEPTH = 4}; /* Have triple indirect */
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typedef u32 block_t; /* 32 bit, host order */
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static inline unsigned long block_to_cpu(block_t n)
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{
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return n;
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}
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static inline block_t cpu_to_block(unsigned long n)
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{
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return n;
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}
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static inline block_t *i_data(struct inode *inode)
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{
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return (block_t *)minix_i(inode)->u.i2_data;
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}
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#define DIRCOUNT 7
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#define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2))
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static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
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{
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int n = 0;
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struct super_block *sb = inode->i_sb;
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if (block < 0) {
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printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
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block, sb->s_bdev);
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return 0;
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}
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if ((u64)block * (u64)sb->s_blocksize >= sb->s_maxbytes)
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return 0;
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if (block < DIRCOUNT) {
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offsets[n++] = block;
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} else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) {
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offsets[n++] = DIRCOUNT;
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offsets[n++] = block;
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} else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) {
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offsets[n++] = DIRCOUNT + 1;
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offsets[n++] = block / INDIRCOUNT(sb);
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offsets[n++] = block % INDIRCOUNT(sb);
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} else {
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block -= INDIRCOUNT(sb) * INDIRCOUNT(sb);
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offsets[n++] = DIRCOUNT + 2;
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offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb);
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offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb);
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offsets[n++] = block % INDIRCOUNT(sb);
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}
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return n;
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}
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#include "itree_common.c"
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int V2_minix_get_block(struct inode * inode, long block,
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struct buffer_head *bh_result, int create)
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{
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return get_block(inode, block, bh_result, create);
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}
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void V2_minix_truncate(struct inode * inode)
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{
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truncate(inode);
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}
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unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
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{
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return nblocks(size, sb);
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}
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