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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2363 | konopa | 1 | /* Basic methods for reading blocks. */ |
| 2 | |||
| 3 | /* Methods: |
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| 4 | * init_block: Allocates memory for working block |
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| 5 | * get_block: Returns requested block according its number |
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| 6 | * read_block: Process reading of requested block |
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| 7 | */ |
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| 8 | |||
| 9 | |||
| 10 | #include <stdio.h> |
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| 11 | #include <async.h> |
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| 12 | #include <sysinfo.h> |
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| 13 | #include "fs.h" |
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| 14 | #include "block.h" |
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| 15 | #include "super.h" |
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| 16 | #include "../rd/rd.h" |
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| 17 | |||
| 18 | |||
| 19 | block_t* work_block; |
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| 20 | |||
| 21 | int init_block() |
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| 22 | { |
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| 23 | |||
| 24 | /* Allocating free space for working block. */ |
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| 25 | work_block = (block_t*)malloc(sizeof(block_t)); |
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| 26 | if (work_block != NULL) |
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| 27 | return TRUE; |
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| 28 | |||
| 29 | return FALSE; |
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| 30 | } |
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| 31 | |||
| 32 | block_t *get_block(register block_num_t block_nr) |
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| 33 | { |
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| 34 | |||
| 35 | if (block_nr == NO_BLOCK) |
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| 36 | return (get_zero_block()); |
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| 37 | |||
| 38 | work_block->b_blocknr = block_nr; |
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| 39 | read_block(work_block); |
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| 40 | |||
| 41 | return work_block; |
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| 42 | } |
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| 43 | |||
| 44 | block_t *get_zero_block() |
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| 45 | { |
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| 46 | |||
| 47 | /* Setting all bytes inside block to 0 */ |
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| 48 | memset(work_block->b.b__data, 0, BLOCK_SIZE); |
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| 49 | |||
| 50 | return work_block; |
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| 51 | } |
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| 52 | |||
| 53 | void read_block(register block_t *bp) |
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| 54 | { |
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| 55 | |||
| 56 | int r; |
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| 57 | offset_t pos, header_size; |
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| 58 | |||
| 59 | header_size = sysinfo_value("rd.header_size"); |
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| 60 | pos = header_size + (offset_t)bp->b_blocknr * BLOCK_SIZE; |
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| 61 | |||
| 62 | /* Reading a block with specified number from ramdisk into shared buffer. */ |
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| 63 | r = async_req_2(rd_phone, RD_READ_BLOCK, pos, BLOCK_SIZE, NULL, NULL); |
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| 64 | if (r < 0) { |
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| 65 | print_console_int("Unrecoverable disk error on RAMDISK, block: %d\n", bp->b_blocknr); |
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| 66 | print_console_int("Error number: %d\n", r); |
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| 67 | status = FS_EIO; |
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| 68 | return; |
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| 69 | } |
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| 70 | |||
| 71 | /* Copy retrieved data from buffer into work block. */ |
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| 72 | memcpy((void *)(bp->b.b__data), (void *)buffer, BLOCK_SIZE); |
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| 73 | status = BLOCK_SIZE; |
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| 74 | } |
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| 75 | |||
| 76 |