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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/hpfs/buffer.c | |
3 | * | |
4 | * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999 | |
5 | * | |
6 | * general buffer i/o | |
7 | */ | |
e8edc6e0 | 8 | #include <linux/sched.h> |
5a0e3ad6 | 9 | #include <linux/slab.h> |
1da177e4 LT |
10 | #include "hpfs_fn.h" |
11 | ||
1da177e4 LT |
12 | /* Map a sector into a buffer and return pointers to it and to the buffer. */ |
13 | ||
14 | void *hpfs_map_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp, | |
15 | int ahead) | |
16 | { | |
17 | struct buffer_head *bh; | |
18 | ||
7dd29d8d MP |
19 | hpfs_lock_assert(s); |
20 | ||
1da177e4 LT |
21 | cond_resched(); |
22 | ||
23 | *bhp = bh = sb_bread(s, secno); | |
24 | if (bh != NULL) | |
25 | return bh->b_data; | |
26 | else { | |
27 | printk("HPFS: hpfs_map_sector: read error\n"); | |
28 | return NULL; | |
29 | } | |
30 | } | |
31 | ||
32 | /* Like hpfs_map_sector but don't read anything */ | |
33 | ||
34 | void *hpfs_get_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp) | |
35 | { | |
36 | struct buffer_head *bh; | |
37 | /*return hpfs_map_sector(s, secno, bhp, 0);*/ | |
38 | ||
7dd29d8d MP |
39 | hpfs_lock_assert(s); |
40 | ||
1da177e4 LT |
41 | cond_resched(); |
42 | ||
43 | if ((*bhp = bh = sb_getblk(s, secno)) != NULL) { | |
44 | if (!buffer_uptodate(bh)) wait_on_buffer(bh); | |
45 | set_buffer_uptodate(bh); | |
46 | return bh->b_data; | |
47 | } else { | |
48 | printk("HPFS: hpfs_get_sector: getblk failed\n"); | |
49 | return NULL; | |
50 | } | |
51 | } | |
52 | ||
53 | /* Map 4 sectors into a 4buffer and return pointers to it and to the buffer. */ | |
54 | ||
55 | void *hpfs_map_4sectors(struct super_block *s, unsigned secno, struct quad_buffer_head *qbh, | |
56 | int ahead) | |
57 | { | |
58 | struct buffer_head *bh; | |
59 | char *data; | |
60 | ||
7dd29d8d MP |
61 | hpfs_lock_assert(s); |
62 | ||
1da177e4 LT |
63 | cond_resched(); |
64 | ||
65 | if (secno & 3) { | |
66 | printk("HPFS: hpfs_map_4sectors: unaligned read\n"); | |
67 | return NULL; | |
68 | } | |
69 | ||
f52720ca | 70 | qbh->data = data = kmalloc(2048, GFP_NOFS); |
1da177e4 LT |
71 | if (!data) { |
72 | printk("HPFS: hpfs_map_4sectors: out of memory\n"); | |
73 | goto bail; | |
74 | } | |
75 | ||
76 | qbh->bh[0] = bh = sb_bread(s, secno); | |
77 | if (!bh) | |
78 | goto bail0; | |
79 | memcpy(data, bh->b_data, 512); | |
80 | ||
81 | qbh->bh[1] = bh = sb_bread(s, secno + 1); | |
82 | if (!bh) | |
83 | goto bail1; | |
84 | memcpy(data + 512, bh->b_data, 512); | |
85 | ||
86 | qbh->bh[2] = bh = sb_bread(s, secno + 2); | |
87 | if (!bh) | |
88 | goto bail2; | |
89 | memcpy(data + 2 * 512, bh->b_data, 512); | |
90 | ||
91 | qbh->bh[3] = bh = sb_bread(s, secno + 3); | |
92 | if (!bh) | |
93 | goto bail3; | |
94 | memcpy(data + 3 * 512, bh->b_data, 512); | |
95 | ||
96 | return data; | |
97 | ||
98 | bail3: | |
99 | brelse(qbh->bh[2]); | |
100 | bail2: | |
101 | brelse(qbh->bh[1]); | |
102 | bail1: | |
103 | brelse(qbh->bh[0]); | |
104 | bail0: | |
105 | kfree(data); | |
106 | printk("HPFS: hpfs_map_4sectors: read error\n"); | |
107 | bail: | |
108 | return NULL; | |
109 | } | |
110 | ||
111 | /* Don't read sectors */ | |
112 | ||
113 | void *hpfs_get_4sectors(struct super_block *s, unsigned secno, | |
114 | struct quad_buffer_head *qbh) | |
115 | { | |
116 | cond_resched(); | |
117 | ||
7dd29d8d MP |
118 | hpfs_lock_assert(s); |
119 | ||
1da177e4 LT |
120 | if (secno & 3) { |
121 | printk("HPFS: hpfs_get_4sectors: unaligned read\n"); | |
122 | return NULL; | |
123 | } | |
124 | ||
125 | /*return hpfs_map_4sectors(s, secno, qbh, 0);*/ | |
126 | if (!(qbh->data = kmalloc(2048, GFP_NOFS))) { | |
127 | printk("HPFS: hpfs_get_4sectors: out of memory\n"); | |
128 | return NULL; | |
129 | } | |
130 | if (!(hpfs_get_sector(s, secno, &qbh->bh[0]))) goto bail0; | |
131 | if (!(hpfs_get_sector(s, secno + 1, &qbh->bh[1]))) goto bail1; | |
132 | if (!(hpfs_get_sector(s, secno + 2, &qbh->bh[2]))) goto bail2; | |
133 | if (!(hpfs_get_sector(s, secno + 3, &qbh->bh[3]))) goto bail3; | |
134 | memcpy(qbh->data, qbh->bh[0]->b_data, 512); | |
135 | memcpy(qbh->data + 512, qbh->bh[1]->b_data, 512); | |
136 | memcpy(qbh->data + 2*512, qbh->bh[2]->b_data, 512); | |
137 | memcpy(qbh->data + 3*512, qbh->bh[3]->b_data, 512); | |
138 | return qbh->data; | |
139 | ||
140 | bail3: brelse(qbh->bh[2]); | |
141 | bail2: brelse(qbh->bh[1]); | |
142 | bail1: brelse(qbh->bh[0]); | |
143 | bail0: | |
144 | return NULL; | |
145 | } | |
146 | ||
147 | ||
148 | void hpfs_brelse4(struct quad_buffer_head *qbh) | |
149 | { | |
150 | brelse(qbh->bh[3]); | |
151 | brelse(qbh->bh[2]); | |
152 | brelse(qbh->bh[1]); | |
153 | brelse(qbh->bh[0]); | |
154 | kfree(qbh->data); | |
155 | } | |
156 | ||
157 | void hpfs_mark_4buffers_dirty(struct quad_buffer_head *qbh) | |
158 | { | |
159 | PRINTK(("hpfs_mark_4buffers_dirty\n")); | |
160 | memcpy(qbh->bh[0]->b_data, qbh->data, 512); | |
161 | memcpy(qbh->bh[1]->b_data, qbh->data + 512, 512); | |
162 | memcpy(qbh->bh[2]->b_data, qbh->data + 2 * 512, 512); | |
163 | memcpy(qbh->bh[3]->b_data, qbh->data + 3 * 512, 512); | |
164 | mark_buffer_dirty(qbh->bh[0]); | |
165 | mark_buffer_dirty(qbh->bh[1]); | |
166 | mark_buffer_dirty(qbh->bh[2]); | |
167 | mark_buffer_dirty(qbh->bh[3]); | |
168 | } |