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,loff_t start,loff_t end,int datasync)21 int hpfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
22 {
23 struct inode *inode = file->f_mapping->host;
24 int ret;
25
26 ret = filemap_write_and_wait_range(file->f_mapping, start, end);
27 if (ret)
28 return ret;
29 return sync_blockdev(inode->i_sb->s_bdev);
30 }
31
32 /*
33 * generic_file_read often calls bmap with non-existing sector,
34 * so we must ignore such errors.
35 */
36
hpfs_bmap(struct inode * inode,unsigned file_secno)37 static secno hpfs_bmap(struct inode *inode, unsigned file_secno)
38 {
39 struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
40 unsigned n, disk_secno;
41 struct fnode *fnode;
42 struct buffer_head *bh;
43 if (BLOCKS(hpfs_i(inode)->mmu_private) <= file_secno) return 0;
44 n = file_secno - hpfs_inode->i_file_sec;
45 if (n < hpfs_inode->i_n_secs) return hpfs_inode->i_disk_sec + n;
46 if (!(fnode = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) return 0;
47 disk_secno = hpfs_bplus_lookup(inode->i_sb, inode, &fnode->btree, file_secno, bh);
48 if (disk_secno == -1) return 0;
49 if (hpfs_chk_sectors(inode->i_sb, disk_secno, 1, "bmap")) return 0;
50 return disk_secno;
51 }
52
hpfs_truncate(struct inode * i)53 static void hpfs_truncate(struct inode *i)
54 {
55 if (IS_IMMUTABLE(i)) return /*-EPERM*/;
56 hpfs_lock_assert(i->i_sb);
57
58 hpfs_i(i)->i_n_secs = 0;
59 i->i_blocks = 1 + ((i->i_size + 511) >> 9);
60 hpfs_i(i)->mmu_private = i->i_size;
61 hpfs_truncate_btree(i->i_sb, i->i_ino, 1, ((i->i_size + 511) >> 9));
62 hpfs_write_inode(i);
63 hpfs_i(i)->i_n_secs = 0;
64 }
65
hpfs_get_block(struct inode * inode,sector_t iblock,struct buffer_head * bh_result,int create)66 static int hpfs_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
67 {
68 int r;
69 secno s;
70 hpfs_lock(inode->i_sb);
71 s = hpfs_bmap(inode, iblock);
72 if (s) {
73 map_bh(bh_result, inode->i_sb, s);
74 goto ret_0;
75 }
76 if (!create) goto ret_0;
77 if (iblock<<9 != hpfs_i(inode)->mmu_private) {
78 BUG();
79 r = -EIO;
80 goto ret_r;
81 }
82 if ((s = hpfs_add_sector_to_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1)) == -1) {
83 hpfs_truncate_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1);
84 r = -ENOSPC;
85 goto ret_r;
86 }
87 inode->i_blocks++;
88 hpfs_i(inode)->mmu_private += 512;
89 set_buffer_new(bh_result);
90 map_bh(bh_result, inode->i_sb, s);
91 ret_0:
92 r = 0;
93 ret_r:
94 hpfs_unlock(inode->i_sb);
95 return r;
96 }
97
hpfs_writepage(struct page * page,struct writeback_control * wbc)98 static int hpfs_writepage(struct page *page, struct writeback_control *wbc)
99 {
100 return block_write_full_page(page,hpfs_get_block, wbc);
101 }
102
hpfs_readpage(struct file * file,struct page * page)103 static int hpfs_readpage(struct file *file, struct page *page)
104 {
105 return block_read_full_page(page,hpfs_get_block);
106 }
107
hpfs_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned flags,struct page ** pagep,void ** fsdata)108 static int hpfs_write_begin(struct file *file, struct address_space *mapping,
109 loff_t pos, unsigned len, unsigned flags,
110 struct page **pagep, void **fsdata)
111 {
112 int ret;
113
114 *pagep = NULL;
115 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
116 hpfs_get_block,
117 &hpfs_i(mapping->host)->mmu_private);
118 if (unlikely(ret)) {
119 loff_t isize;
120 hpfs_lock(mapping->host->i_sb);
121 isize = mapping->host->i_size;
122 if (pos + len > isize)
123 vmtruncate(mapping->host, isize);
124 hpfs_unlock(mapping->host->i_sb);
125 }
126
127 return ret;
128 }
129
_hpfs_bmap(struct address_space * mapping,sector_t block)130 static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
131 {
132 return generic_block_bmap(mapping,block,hpfs_get_block);
133 }
134
135 const struct address_space_operations hpfs_aops = {
136 .readpage = hpfs_readpage,
137 .writepage = hpfs_writepage,
138 .write_begin = hpfs_write_begin,
139 .write_end = generic_write_end,
140 .bmap = _hpfs_bmap
141 };
142
hpfs_file_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)143 static ssize_t hpfs_file_write(struct file *file, const char __user *buf,
144 size_t count, loff_t *ppos)
145 {
146 ssize_t retval;
147
148 retval = do_sync_write(file, buf, count, ppos);
149 if (retval > 0) {
150 hpfs_lock(file->f_path.dentry->d_sb);
151 hpfs_i(file->f_path.dentry->d_inode)->i_dirty = 1;
152 hpfs_unlock(file->f_path.dentry->d_sb);
153 }
154 return retval;
155 }
156
157 const struct file_operations hpfs_file_ops =
158 {
159 .llseek = generic_file_llseek,
160 .read = do_sync_read,
161 .aio_read = generic_file_aio_read,
162 .write = hpfs_file_write,
163 .aio_write = generic_file_aio_write,
164 .mmap = generic_file_mmap,
165 .release = hpfs_file_release,
166 .fsync = hpfs_file_fsync,
167 .splice_read = generic_file_splice_read,
168 };
169
170 const struct inode_operations hpfs_file_iops =
171 {
172 .truncate = hpfs_truncate,
173 .setattr = hpfs_setattr,
174 };
175