1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
|
/*
* linux/fs/hpfs/file.c
*
* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
*
* file VFS functions
*/
#include <linux/smp_lock.h>
#include "hpfs_fn.h"
#define BLOCKS(size) (((size) + 511) >> 9)
static int hpfs_file_release(struct inode *inode, struct file *file)
{
lock_kernel();
hpfs_write_if_changed(inode);
unlock_kernel();
return 0;
}
int hpfs_file_fsync(struct file *file, int datasync)
{
/*return file_fsync(file, datasync);*/
return 0; /* Don't fsync :-) */
}
/*
* generic_file_read often calls bmap with non-existing sector,
* so we must ignore such errors.
*/
static secno hpfs_bmap(struct inode *inode, unsigned file_secno)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
unsigned n, disk_secno;
struct fnode *fnode;
struct buffer_head *bh;
if (BLOCKS(hpfs_i(inode)->mmu_private) <= file_secno) return 0;
n = file_secno - hpfs_inode->i_file_sec;
if (n < hpfs_inode->i_n_secs) return hpfs_inode->i_disk_sec + n;
if (!(fnode = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) return 0;
disk_secno = hpfs_bplus_lookup(inode->i_sb, inode, &fnode->btree, file_secno, bh);
if (disk_secno == -1) return 0;
if (hpfs_chk_sectors(inode->i_sb, disk_secno, 1, "bmap")) return 0;
return disk_secno;
}
static void hpfs_truncate(struct inode *i)
{
if (IS_IMMUTABLE(i)) return /*-EPERM*/;
lock_kernel();
hpfs_i(i)->i_n_secs = 0;
i->i_blocks = 1 + ((i->i_size + 511) >> 9);
hpfs_i(i)->mmu_private = i->i_size;
hpfs_truncate_btree(i->i_sb, i->i_ino, 1, ((i->i_size + 511) >> 9));
hpfs_write_inode(i);
hpfs_i(i)->i_n_secs = 0;
unlock_kernel();
}
static int hpfs_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
{
secno s;
s = hpfs_bmap(inode, iblock);
if (s) {
map_bh(bh_result, inode->i_sb, s);
return 0;
}
if (!create) return 0;
if (iblock<<9 != hpfs_i(inode)->mmu_private) {
BUG();
return -EIO;
}
if ((s = hpfs_add_sector_to_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1)) == -1) {
hpfs_truncate_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1);
return -ENOSPC;
}
inode->i_blocks++;
hpfs_i(inode)->mmu_private += 512;
set_buffer_new(bh_result);
map_bh(bh_result, inode->i_sb, s);
return 0;
}
static int hpfs_writepage(struct page *page, struct writeback_control *wbc)
{
return block_write_full_page(page,hpfs_get_block, wbc);
}
static int hpfs_readpage(struct file *file, struct page *page)
{
return block_read_full_page(page,hpfs_get_block);
}
static int hpfs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
int ret;
*pagep = NULL;
ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
hpfs_get_block,
&hpfs_i(mapping->host)->mmu_private);
if (unlikely(ret)) {
loff_t isize = mapping->host->i_size;
if (pos + len > isize)
vmtruncate(mapping->host, isize);
}
return ret;
}
static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
{
return generic_block_bmap(mapping,block,hpfs_get_block);
}
const struct address_space_operations hpfs_aops = {
.readpage = hpfs_readpage,
.writepage = hpfs_writepage,
.write_begin = hpfs_write_begin,
.write_end = generic_write_end,
.bmap = _hpfs_bmap
};
static ssize_t hpfs_file_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
ssize_t retval;
retval = do_sync_write(file, buf, count, ppos);
if (retval > 0)
hpfs_i(file->f_path.dentry->d_inode)->i_dirty = 1;
return retval;
}
const struct file_operations hpfs_file_ops =
{
.llseek = generic_file_llseek,
.read = do_sync_read,
.aio_read = generic_file_aio_read,
.write = hpfs_file_write,
.aio_write = generic_file_aio_write,
.mmap = generic_file_mmap,
.release = hpfs_file_release,
.fsync = hpfs_file_fsync,
.splice_read = generic_file_splice_read,
};
const struct inode_operations hpfs_file_iops =
{
.truncate = hpfs_truncate,
.setattr = hpfs_setattr,
};
|
