1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/hpfs/file.c
4 *
5 * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
6 *
7 * file VFS functions
8 */
9
10 #include "hpfs_fn.h"
11 #include <linux/mpage.h>
12
13 #define BLOCKS(size) (((size) + 511) >> 9)
14
hpfs_file_release(struct inode * inode,struct file * file)15 static int hpfs_file_release(struct inode *inode, struct file *file)
16 {
17 hpfs_lock(inode->i_sb);
18 hpfs_write_if_changed(inode);
19 hpfs_unlock(inode->i_sb);
20 return 0;
21 }
22
hpfs_file_fsync(struct file * file,loff_t start,loff_t end,int datasync)23 int hpfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
24 {
25 struct inode *inode = file->f_mapping->host;
26 int ret;
27
28 ret = file_write_and_wait_range(file, start, end);
29 if (ret)
30 return ret;
31 return sync_blockdev(inode->i_sb->s_bdev);
32 }
33
34 /*
35 * generic_file_read often calls bmap with non-existing sector,
36 * so we must ignore such errors.
37 */
38
hpfs_bmap(struct inode * inode,unsigned file_secno,unsigned * n_secs)39 static secno hpfs_bmap(struct inode *inode, unsigned file_secno, unsigned *n_secs)
40 {
41 struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
42 unsigned n, disk_secno;
43 struct fnode *fnode;
44 struct buffer_head *bh;
45 if (BLOCKS(hpfs_i(inode)->mmu_private) <= file_secno) return 0;
46 n = file_secno - hpfs_inode->i_file_sec;
47 if (n < hpfs_inode->i_n_secs) {
48 *n_secs = hpfs_inode->i_n_secs - n;
49 return hpfs_inode->i_disk_sec + n;
50 }
51 if (!(fnode = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) return 0;
52 disk_secno = hpfs_bplus_lookup(inode->i_sb, inode, &fnode->btree, file_secno, bh);
53 if (disk_secno == -1) return 0;
54 if (hpfs_chk_sectors(inode->i_sb, disk_secno, 1, "bmap")) return 0;
55 n = file_secno - hpfs_inode->i_file_sec;
56 if (n < hpfs_inode->i_n_secs) {
57 *n_secs = hpfs_inode->i_n_secs - n;
58 return hpfs_inode->i_disk_sec + n;
59 }
60 *n_secs = 1;
61 return disk_secno;
62 }
63
hpfs_truncate(struct inode * i)64 void hpfs_truncate(struct inode *i)
65 {
66 if (IS_IMMUTABLE(i)) return /*-EPERM*/;
67 hpfs_lock_assert(i->i_sb);
68
69 hpfs_i(i)->i_n_secs = 0;
70 i->i_blocks = 1 + ((i->i_size + 511) >> 9);
71 hpfs_i(i)->mmu_private = i->i_size;
72 hpfs_truncate_btree(i->i_sb, i->i_ino, 1, ((i->i_size + 511) >> 9));
73 hpfs_write_inode(i);
74 hpfs_i(i)->i_n_secs = 0;
75 }
76
hpfs_get_block(struct inode * inode,sector_t iblock,struct buffer_head * bh_result,int create)77 static int hpfs_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
78 {
79 int r;
80 secno s;
81 unsigned n_secs;
82 hpfs_lock(inode->i_sb);
83 s = hpfs_bmap(inode, iblock, &n_secs);
84 if (s) {
85 if (bh_result->b_size >> 9 < n_secs)
86 n_secs = bh_result->b_size >> 9;
87 n_secs = hpfs_search_hotfix_map_for_range(inode->i_sb, s, n_secs);
88 if (unlikely(!n_secs)) {
89 s = hpfs_search_hotfix_map(inode->i_sb, s);
90 n_secs = 1;
91 }
92 map_bh(bh_result, inode->i_sb, s);
93 bh_result->b_size = n_secs << 9;
94 goto ret_0;
95 }
96 if (!create) goto ret_0;
97 if (iblock<<9 != hpfs_i(inode)->mmu_private) {
98 BUG();
99 r = -EIO;
100 goto ret_r;
101 }
102 if ((s = hpfs_add_sector_to_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1)) == -1) {
103 hpfs_truncate_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1);
104 r = -ENOSPC;
105 goto ret_r;
106 }
107 inode->i_blocks++;
108 hpfs_i(inode)->mmu_private += 512;
109 set_buffer_new(bh_result);
110 map_bh(bh_result, inode->i_sb, hpfs_search_hotfix_map(inode->i_sb, s));
111 ret_0:
112 r = 0;
113 ret_r:
114 hpfs_unlock(inode->i_sb);
115 return r;
116 }
117
hpfs_readpage(struct file * file,struct page * page)118 static int hpfs_readpage(struct file *file, struct page *page)
119 {
120 return mpage_readpage(page, hpfs_get_block);
121 }
122
hpfs_writepage(struct page * page,struct writeback_control * wbc)123 static int hpfs_writepage(struct page *page, struct writeback_control *wbc)
124 {
125 return block_write_full_page(page, hpfs_get_block, wbc);
126 }
127
hpfs_readpages(struct file * file,struct address_space * mapping,struct list_head * pages,unsigned nr_pages)128 static int hpfs_readpages(struct file *file, struct address_space *mapping,
129 struct list_head *pages, unsigned nr_pages)
130 {
131 return mpage_readpages(mapping, pages, nr_pages, hpfs_get_block);
132 }
133
hpfs_writepages(struct address_space * mapping,struct writeback_control * wbc)134 static int hpfs_writepages(struct address_space *mapping,
135 struct writeback_control *wbc)
136 {
137 return mpage_writepages(mapping, wbc, hpfs_get_block);
138 }
139
hpfs_write_failed(struct address_space * mapping,loff_t to)140 static void hpfs_write_failed(struct address_space *mapping, loff_t to)
141 {
142 struct inode *inode = mapping->host;
143
144 hpfs_lock(inode->i_sb);
145
146 if (to > inode->i_size) {
147 truncate_pagecache(inode, inode->i_size);
148 hpfs_truncate(inode);
149 }
150
151 hpfs_unlock(inode->i_sb);
152 }
153
hpfs_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned flags,struct page ** pagep,void ** fsdata)154 static int hpfs_write_begin(struct file *file, struct address_space *mapping,
155 loff_t pos, unsigned len, unsigned flags,
156 struct page **pagep, void **fsdata)
157 {
158 int ret;
159
160 *pagep = NULL;
161 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
162 hpfs_get_block,
163 &hpfs_i(mapping->host)->mmu_private);
164 if (unlikely(ret))
165 hpfs_write_failed(mapping, pos + len);
166
167 return ret;
168 }
169
hpfs_write_end(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned copied,struct page * pagep,void * fsdata)170 static int hpfs_write_end(struct file *file, struct address_space *mapping,
171 loff_t pos, unsigned len, unsigned copied,
172 struct page *pagep, void *fsdata)
173 {
174 struct inode *inode = mapping->host;
175 int err;
176 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
177 if (err < len)
178 hpfs_write_failed(mapping, pos + len);
179 if (!(err < 0)) {
180 /* make sure we write it on close, if not earlier */
181 hpfs_lock(inode->i_sb);
182 hpfs_i(inode)->i_dirty = 1;
183 hpfs_unlock(inode->i_sb);
184 }
185 return err;
186 }
187
_hpfs_bmap(struct address_space * mapping,sector_t block)188 static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
189 {
190 return generic_block_bmap(mapping, block, hpfs_get_block);
191 }
192
hpfs_fiemap(struct inode * inode,struct fiemap_extent_info * fieinfo,u64 start,u64 len)193 static int hpfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 len)
194 {
195 return generic_block_fiemap(inode, fieinfo, start, len, hpfs_get_block);
196 }
197
198 const struct address_space_operations hpfs_aops = {
199 .readpage = hpfs_readpage,
200 .writepage = hpfs_writepage,
201 .readpages = hpfs_readpages,
202 .writepages = hpfs_writepages,
203 .write_begin = hpfs_write_begin,
204 .write_end = hpfs_write_end,
205 .bmap = _hpfs_bmap
206 };
207
208 const struct file_operations hpfs_file_ops =
209 {
210 .llseek = generic_file_llseek,
211 .read_iter = generic_file_read_iter,
212 .write_iter = generic_file_write_iter,
213 .mmap = generic_file_mmap,
214 .release = hpfs_file_release,
215 .fsync = hpfs_file_fsync,
216 .splice_read = generic_file_splice_read,
217 .unlocked_ioctl = hpfs_ioctl,
218 };
219
220 const struct inode_operations hpfs_file_iops =
221 {
222 .setattr = hpfs_setattr,
223 .fiemap = hpfs_fiemap,
224 };
225