Commit | Line | Data |
---|---|---|
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> |
1da177e4 LT |
9 | #include "hpfs_fn.h" |
10 | ||
11 | void hpfs_lock_creation(struct super_block *s) | |
12 | { | |
13 | #ifdef DEBUG_LOCKS | |
14 | printk("lock creation\n"); | |
15 | #endif | |
16 | down(&hpfs_sb(s)->hpfs_creation_de); | |
17 | } | |
18 | ||
19 | void hpfs_unlock_creation(struct super_block *s) | |
20 | { | |
21 | #ifdef DEBUG_LOCKS | |
22 | printk("unlock creation\n"); | |
23 | #endif | |
24 | up(&hpfs_sb(s)->hpfs_creation_de); | |
25 | } | |
26 | ||
27 | /* Map a sector into a buffer and return pointers to it and to the buffer. */ | |
28 | ||
29 | void *hpfs_map_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp, | |
30 | int ahead) | |
31 | { | |
32 | struct buffer_head *bh; | |
33 | ||
34 | cond_resched(); | |
35 | ||
36 | *bhp = bh = sb_bread(s, secno); | |
37 | if (bh != NULL) | |
38 | return bh->b_data; | |
39 | else { | |
40 | printk("HPFS: hpfs_map_sector: read error\n"); | |
41 | return NULL; | |
42 | } | |
43 | } | |
44 | ||
45 | /* Like hpfs_map_sector but don't read anything */ | |
46 | ||
47 | void *hpfs_get_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp) | |
48 | { | |
49 | struct buffer_head *bh; | |
50 | /*return hpfs_map_sector(s, secno, bhp, 0);*/ | |
51 | ||
52 | cond_resched(); | |
53 | ||
54 | if ((*bhp = bh = sb_getblk(s, secno)) != NULL) { | |
55 | if (!buffer_uptodate(bh)) wait_on_buffer(bh); | |
56 | set_buffer_uptodate(bh); | |
57 | return bh->b_data; | |
58 | } else { | |
59 | printk("HPFS: hpfs_get_sector: getblk failed\n"); | |
60 | return NULL; | |
61 | } | |
62 | } | |
63 | ||
64 | /* Map 4 sectors into a 4buffer and return pointers to it and to the buffer. */ | |
65 | ||
66 | void *hpfs_map_4sectors(struct super_block *s, unsigned secno, struct quad_buffer_head *qbh, | |
67 | int ahead) | |
68 | { | |
69 | struct buffer_head *bh; | |
70 | char *data; | |
71 | ||
72 | cond_resched(); | |
73 | ||
74 | if (secno & 3) { | |
75 | printk("HPFS: hpfs_map_4sectors: unaligned read\n"); | |
76 | return NULL; | |
77 | } | |
78 | ||
f52720ca | 79 | qbh->data = data = kmalloc(2048, GFP_NOFS); |
1da177e4 LT |
80 | if (!data) { |
81 | printk("HPFS: hpfs_map_4sectors: out of memory\n"); | |
82 | goto bail; | |
83 | } | |
84 | ||
85 | qbh->bh[0] = bh = sb_bread(s, secno); | |
86 | if (!bh) | |
87 | goto bail0; | |
88 | memcpy(data, bh->b_data, 512); | |
89 | ||
90 | qbh->bh[1] = bh = sb_bread(s, secno + 1); | |
91 | if (!bh) | |
92 | goto bail1; | |
93 | memcpy(data + 512, bh->b_data, 512); | |
94 | ||
95 | qbh->bh[2] = bh = sb_bread(s, secno + 2); | |
96 | if (!bh) | |
97 | goto bail2; | |
98 | memcpy(data + 2 * 512, bh->b_data, 512); | |
99 | ||
100 | qbh->bh[3] = bh = sb_bread(s, secno + 3); | |
101 | if (!bh) | |
102 | goto bail3; | |
103 | memcpy(data + 3 * 512, bh->b_data, 512); | |
104 | ||
105 | return data; | |
106 | ||
107 | bail3: | |
108 | brelse(qbh->bh[2]); | |
109 | bail2: | |
110 | brelse(qbh->bh[1]); | |
111 | bail1: | |
112 | brelse(qbh->bh[0]); | |
113 | bail0: | |
114 | kfree(data); | |
115 | printk("HPFS: hpfs_map_4sectors: read error\n"); | |
116 | bail: | |
117 | return NULL; | |
118 | } | |
119 | ||
120 | /* Don't read sectors */ | |
121 | ||
122 | void *hpfs_get_4sectors(struct super_block *s, unsigned secno, | |
123 | struct quad_buffer_head *qbh) | |
124 | { | |
125 | cond_resched(); | |
126 | ||
127 | if (secno & 3) { | |
128 | printk("HPFS: hpfs_get_4sectors: unaligned read\n"); | |
129 | return NULL; | |
130 | } | |
131 | ||
132 | /*return hpfs_map_4sectors(s, secno, qbh, 0);*/ | |
133 | if (!(qbh->data = kmalloc(2048, GFP_NOFS))) { | |
134 | printk("HPFS: hpfs_get_4sectors: out of memory\n"); | |
135 | return NULL; | |
136 | } | |
137 | if (!(hpfs_get_sector(s, secno, &qbh->bh[0]))) goto bail0; | |
138 | if (!(hpfs_get_sector(s, secno + 1, &qbh->bh[1]))) goto bail1; | |
139 | if (!(hpfs_get_sector(s, secno + 2, &qbh->bh[2]))) goto bail2; | |
140 | if (!(hpfs_get_sector(s, secno + 3, &qbh->bh[3]))) goto bail3; | |
141 | memcpy(qbh->data, qbh->bh[0]->b_data, 512); | |
142 | memcpy(qbh->data + 512, qbh->bh[1]->b_data, 512); | |
143 | memcpy(qbh->data + 2*512, qbh->bh[2]->b_data, 512); | |
144 | memcpy(qbh->data + 3*512, qbh->bh[3]->b_data, 512); | |
145 | return qbh->data; | |
146 | ||
147 | bail3: brelse(qbh->bh[2]); | |
148 | bail2: brelse(qbh->bh[1]); | |
149 | bail1: brelse(qbh->bh[0]); | |
150 | bail0: | |
151 | return NULL; | |
152 | } | |
153 | ||
154 | ||
155 | void hpfs_brelse4(struct quad_buffer_head *qbh) | |
156 | { | |
157 | brelse(qbh->bh[3]); | |
158 | brelse(qbh->bh[2]); | |
159 | brelse(qbh->bh[1]); | |
160 | brelse(qbh->bh[0]); | |
161 | kfree(qbh->data); | |
162 | } | |
163 | ||
164 | void hpfs_mark_4buffers_dirty(struct quad_buffer_head *qbh) | |
165 | { | |
166 | PRINTK(("hpfs_mark_4buffers_dirty\n")); | |
167 | memcpy(qbh->bh[0]->b_data, qbh->data, 512); | |
168 | memcpy(qbh->bh[1]->b_data, qbh->data + 512, 512); | |
169 | memcpy(qbh->bh[2]->b_data, qbh->data + 2 * 512, 512); | |
170 | memcpy(qbh->bh[3]->b_data, qbh->data + 3 * 512, 512); | |
171 | mark_buffer_dirty(qbh->bh[0]); | |
172 | mark_buffer_dirty(qbh->bh[1]); | |
173 | mark_buffer_dirty(qbh->bh[2]); | |
174 | mark_buffer_dirty(qbh->bh[3]); | |
175 | } |