1 /*
2 * linux/fs/hpfs/file.c
3 *
4 * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5 *
6 * file VFS functions
7 */
8
9 #include "hpfs_fn.h"
10
11 #define BLOCKS(size) (((size) + 511) >> 9)
12
hpfs_file_release(struct inode * inode,struct file * file)13 static int hpfs_file_release(struct inode *inode, struct file *file)
14 {
15 hpfs_lock(inode->i_sb);
16 hpfs_write_if_changed(inode);
17 hpfs_unlock(inode->i_sb);
18 return 0;
19 }
20
hpfs_file_fsync(struct file * file,int datasync)21 int hpfs_file_fsync(struct file *file, int datasync)
22 {
23 struct inode *inode = file->f_mapping->host;
24 return sync_blockdev(inode->i_sb->s_bdev);
25 }
26
27 /*
28 * generic_file_read often calls bmap with non-existing sector,
29 * so we must ignore such errors.
30 */
31
hpfs_bmap(struct inode * inode,unsigned file_secno)32 static secno hpfs_bmap(struct inode *inode, unsigned file_secno)
33 {
34 struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
35 unsigned n, disk_secno;
36 struct fnode *fnode;
37 struct buffer_head *bh;
38 if (BLOCKS(hpfs_i(inode)->mmu_private) <= file_secno) return 0;
39 n = file_secno - hpfs_inode->i_file_sec;
40 if (n < hpfs_inode->i_n_secs) return hpfs_inode->i_disk_sec + n;
41 if (!(fnode = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) return 0;
42 disk_secno = hpfs_bplus_lookup(inode->i_sb, inode, &fnode->btree, file_secno, bh);
43 if (disk_secno == -1) return 0;
44 if (hpfs_chk_sectors(inode->i_sb, disk_secno, 1, "bmap")) return 0;
45 return disk_secno;
46 }
47
hpfs_truncate(struct inode * i)48 static void hpfs_truncate(struct inode *i)
49 {
50 if (IS_IMMUTABLE(i)) return /*-EPERM*/;
51 hpfs_lock_assert(i->i_sb);
52
53 hpfs_i(i)->i_n_secs = 0;
54 i->i_blocks = 1 + ((i->i_size + 511) >> 9);
55 hpfs_i(i)->mmu_private = i->i_size;
56 hpfs_truncate_btree(i->i_sb, i->i_ino, 1, ((i->i_size + 511) >> 9));
57 hpfs_write_inode(i);
58 hpfs_i(i)->i_n_secs = 0;
59 }
60
hpfs_get_block(struct inode * inode,sector_t iblock,struct buffer_head * bh_result,int create)61 static int hpfs_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
62 {
63 int r;
64 secno s;
65 hpfs_lock(inode->i_sb);
66 s = hpfs_bmap(inode, iblock);
67 if (s) {
68 map_bh(bh_result, inode->i_sb, s);
69 goto ret_0;
70 }
71 if (!create) goto ret_0;
72 if (iblock<<9 != hpfs_i(inode)->mmu_private) {
73 BUG();
74 r = -EIO;
75 goto ret_r;
76 }
77 if ((s = hpfs_add_sector_to_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1)) == -1) {
78 hpfs_truncate_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1);
79 r = -ENOSPC;
80 goto ret_r;
81 }
82 inode->i_blocks++;
83 hpfs_i(inode)->mmu_private += 512;
84 set_buffer_new(bh_result);
85 map_bh(bh_result, inode->i_sb, s);
86 ret_0:
87 r = 0;
88 ret_r:
89 hpfs_unlock(inode->i_sb);
90 return r;
91 }
92
hpfs_writepage(struct page * page,struct writeback_control * wbc)93 static int hpfs_writepage(struct page *page, struct writeback_control *wbc)
94 {
95 return block_write_full_page(page,hpfs_get_block, wbc);
96 }
97
hpfs_readpage(struct file * file,struct page * page)98 static int hpfs_readpage(struct file *file, struct page *page)
99 {
100 return block_read_full_page(page,hpfs_get_block);
101 }
102
hpfs_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned flags,struct page ** pagep,void ** fsdata)103 static int hpfs_write_begin(struct file *file, struct address_space *mapping,
104 loff_t pos, unsigned len, unsigned flags,
105 struct page **pagep, void **fsdata)
106 {
107 int ret;
108
109 *pagep = NULL;
110 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
111 hpfs_get_block,
112 &hpfs_i(mapping->host)->mmu_private);
113 if (unlikely(ret)) {
114 loff_t isize = mapping->host->i_size;
115 if (pos + len > isize)
116 vmtruncate(mapping->host, isize);
117 }
118
119 return ret;
120 }
121
_hpfs_bmap(struct address_space * mapping,sector_t block)122 static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
123 {
124 return generic_block_bmap(mapping,block,hpfs_get_block);
125 }
126
127 const struct address_space_operations hpfs_aops = {
128 .readpage = hpfs_readpage,
129 .writepage = hpfs_writepage,
130 .write_begin = hpfs_write_begin,
131 .write_end = generic_write_end,
132 .bmap = _hpfs_bmap
133 };
134
hpfs_file_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)135 static ssize_t hpfs_file_write(struct file *file, const char __user *buf,
136 size_t count, loff_t *ppos)
137 {
138 ssize_t retval;
139
140 retval = do_sync_write(file, buf, count, ppos);
141 if (retval > 0) {
142 hpfs_lock(file->f_path.dentry->d_sb);
143 hpfs_i(file->f_path.dentry->d_inode)->i_dirty = 1;
144 hpfs_unlock(file->f_path.dentry->d_sb);
145 }
146 return retval;
147 }
148
149 const struct file_operations hpfs_file_ops =
150 {
151 .llseek = generic_file_llseek,
152 .read = do_sync_read,
153 .aio_read = generic_file_aio_read,
154 .write = hpfs_file_write,
155 .aio_write = generic_file_aio_write,
156 .mmap = generic_file_mmap,
157 .release = hpfs_file_release,
158 .fsync = hpfs_file_fsync,
159 .splice_read = generic_file_splice_read,
160 };
161
162 const struct inode_operations hpfs_file_iops =
163 {
164 .truncate = hpfs_truncate,
165 .setattr = hpfs_setattr,
166 };
167