| 1 | |
| 2 | #include <linux/buffer_head.h>
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| 3 | #include "minix.h"
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| 4 |
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| 5 | enum {DIRECT = 7, DEPTH = 4};
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| 6 |
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| 7 | typedef u32 block_t;
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| 8 |
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| 9 | static inline unsigned long block_to_cpu(block_t n)
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| 10 | {
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| 11 | return n;
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| 12 | }
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| 13 |
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| 14 | static inline block_t cpu_to_block(unsigned long n)
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| 15 | {
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| 16 | return n;
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| 17 | }
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| 18 |
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| 19 | static inline block_t *i_data(struct inode *inode)
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| 20 | {
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| 21 | return (block_t *)minix_i(inode)->u.i2_data;
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| 22 | }
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| 23 |
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| 24 | #define DIRCOUNT 7
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| 25 | #define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2))
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| 26 |
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| 27 | static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
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| 28 | {
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| 29 | int n = 0;
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| 30 | struct super_block *sb = inode->i_sb;
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| 31 |
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| 32 | if (block < 0) {
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| 33 | printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
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| 34 | block, sb->s_bdev);
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| 35 | return 0;
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| 36 | }
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| 37 | if ((u64)block * (u64)sb->s_blocksize >= sb->s_maxbytes)
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| 38 | return 0;
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| 39 |
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| 40 | if (block < DIRCOUNT) {
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| 41 | offsets[n++] = block;
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| 42 | } else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) {
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| 43 | offsets[n++] = DIRCOUNT;
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| 44 | offsets[n++] = block;
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| 45 | } else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) {
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| 46 | offsets[n++] = DIRCOUNT + 1;
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| 47 | offsets[n++] = block / INDIRCOUNT(sb);
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| 48 | offsets[n++] = block % INDIRCOUNT(sb);
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| 49 | } else {
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| 50 | block -= INDIRCOUNT(sb) * INDIRCOUNT(sb);
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| 51 | offsets[n++] = DIRCOUNT + 2;
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| 52 | offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb);
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| 53 | offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb);
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| 54 | offsets[n++] = block % INDIRCOUNT(sb);
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| 55 | }
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| 56 | return n;
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| 57 | }
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| 58 |
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| 59 | #include "itree_common.c"
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| 60 |
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| 61 | int V2_minix_get_block(struct inode * inode, long block,
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| 62 | struct buffer_head *bh_result, int create)
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| 63 | {
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| 64 | return get_block(inode, block, bh_result, create);
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| 65 | }
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| 66 |
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| 67 | void V2_minix_truncate(struct inode * inode)
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| 68 | {
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| 69 | truncate(inode);
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| 70 | }
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| 71 |
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| 72 | unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
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| 73 | {
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| 74 | return nblocks(size, sb);
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| 75 | }
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