Rev 2363 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
2435 | jelen | 1 | /* |
2 | * Copyright (c) 1987,1997, Prentice Hall |
||
3 | * All rights reserved. |
||
4 | * |
||
5 | * Redistribution and use of the MINIX operating system in source and |
||
6 | * binary forms, with or without modification, are permitted provided |
||
7 | * that the following conditions are met: |
||
2363 | konopa | 8 | |
2435 | jelen | 9 | * - Redistributions of source code must retain the above copyright |
10 | * notice, this list of conditions and the following disclaimer. |
||
11 | |||
12 | * - Redistributions in binary form must reproduce the above |
||
13 | * copyright notice, this list of conditions and the following |
||
14 | * disclaimer in the documentation and/or other materials provided |
||
15 | * with the distribution. |
||
16 | |||
17 | * - Neither the name of Prentice Hall nor the names of the software |
||
18 | * authors or contributors may be used to endorse or promote |
||
19 | * products derived from this software without specific prior |
||
20 | * written permission. |
||
21 | |||
22 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS, AUTHORS, AND |
||
23 | * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||
24 | * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
||
25 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
26 | * IN NO EVENT SHALL PRENTICE HALL OR ANY AUTHORS OR CONTRIBUTORS BE |
||
27 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
||
28 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
||
29 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
||
30 | * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
||
31 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE |
||
32 | * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, |
||
33 | * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
2363 | konopa | 34 | */ |
2435 | jelen | 35 | |
36 | /** @addtogroup FileSystemImpl |
||
37 | * @{ |
||
38 | */ |
||
2363 | konopa | 39 | |
2435 | jelen | 40 | /** |
41 | * @file block.c |
||
42 | * @brief Basic methods for reading blocks. |
||
43 | */ |
||
2363 | konopa | 44 | |
45 | #include <stdio.h> |
||
46 | #include <async.h> |
||
47 | #include <sysinfo.h> |
||
48 | #include "fs.h" |
||
49 | #include "block.h" |
||
50 | #include "super.h" |
||
51 | #include "../rd/rd.h" |
||
52 | |||
2435 | jelen | 53 | block_t* work_block; /**< A temporary variable for storing the working block */ |
2363 | konopa | 54 | |
2435 | jelen | 55 | /** |
56 | * Allocates memory for working block |
||
57 | */ |
||
2363 | konopa | 58 | int init_block() |
59 | { |
||
60 | |||
61 | /* Allocating free space for working block. */ |
||
62 | work_block = (block_t*)malloc(sizeof(block_t)); |
||
63 | if (work_block != NULL) |
||
64 | return TRUE; |
||
65 | |||
66 | return FALSE; |
||
67 | } |
||
68 | |||
2435 | jelen | 69 | /** |
70 | * Returns requested block according its number |
||
71 | */ |
||
2363 | konopa | 72 | block_t *get_block(register block_num_t block_nr) |
73 | { |
||
74 | |||
75 | if (block_nr == NO_BLOCK) |
||
76 | return (get_zero_block()); |
||
77 | |||
78 | work_block->b_blocknr = block_nr; |
||
79 | read_block(work_block); |
||
80 | |||
81 | return work_block; |
||
82 | } |
||
83 | |||
2435 | jelen | 84 | /** |
85 | * Return a block filled with zeroes |
||
86 | */ |
||
2363 | konopa | 87 | block_t *get_zero_block() |
88 | { |
||
89 | |||
90 | /* Setting all bytes inside block to 0 */ |
||
91 | memset(work_block->b.b__data, 0, BLOCK_SIZE); |
||
92 | |||
93 | return work_block; |
||
94 | } |
||
95 | |||
2435 | jelen | 96 | /** |
97 | * Process reading of requested block |
||
98 | */ |
||
2363 | konopa | 99 | void read_block(register block_t *bp) |
100 | { |
||
101 | |||
102 | int r; |
||
103 | offset_t pos, header_size; |
||
104 | |||
105 | header_size = sysinfo_value("rd.header_size"); |
||
106 | pos = header_size + (offset_t)bp->b_blocknr * BLOCK_SIZE; |
||
107 | |||
108 | /* Reading a block with specified number from ramdisk into shared buffer. */ |
||
109 | r = async_req_2(rd_phone, RD_READ_BLOCK, pos, BLOCK_SIZE, NULL, NULL); |
||
110 | if (r < 0) { |
||
111 | print_console_int("Unrecoverable disk error on RAMDISK, block: %d\n", bp->b_blocknr); |
||
112 | print_console_int("Error number: %d\n", r); |
||
113 | status = FS_EIO; |
||
114 | return; |
||
115 | } |
||
116 | |||
117 | /* Copy retrieved data from buffer into work block. */ |
||
118 | memcpy((void *)(bp->b.b__data), (void *)buffer, BLOCK_SIZE); |
||
119 | status = BLOCK_SIZE; |
||
120 | } |
||
121 | |||
122 | |||
2435 | jelen | 123 | /** |
124 | * } |
||
125 | */ |
||
126 |