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 #include <linux/iomap.h>
13 #include <linux/fiemap.h>
14
15 #define BLOCKS(size) (((size) + 511) >> 9)
16
hpfs_file_release(struct inode * inode,struct file * file)17 static int hpfs_file_release(struct inode *inode, struct file *file)
18 {
19 hpfs_lock(inode->i_sb);
20 hpfs_write_if_changed(inode);
21 hpfs_unlock(inode->i_sb);
22 return 0;
23 }
24
hpfs_file_fsync(struct file * file,loff_t start,loff_t end,int datasync)25 int hpfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
26 {
27 struct inode *inode = file->f_mapping->host;
28 int ret;
29
30 ret = file_write_and_wait_range(file, start, end);
31 if (ret)
32 return ret;
33 return sync_blockdev(inode->i_sb->s_bdev);
34 }
35
36 /*
37 * generic_file_read often calls bmap with non-existing sector,
38 * so we must ignore such errors.
39 */
40
hpfs_bmap(struct inode * inode,unsigned file_secno,unsigned * n_secs)41 static secno hpfs_bmap(struct inode *inode, unsigned file_secno, unsigned *n_secs)
42 {
43 struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
44 unsigned n, disk_secno;
45 struct fnode *fnode;
46 struct buffer_head *bh;
47 if (BLOCKS(hpfs_i(inode)->mmu_private) <= file_secno) return 0;
48 n = file_secno - hpfs_inode->i_file_sec;
49 if (n < hpfs_inode->i_n_secs) {
50 *n_secs = hpfs_inode->i_n_secs - n;
51 return hpfs_inode->i_disk_sec + n;
52 }
53 if (!(fnode = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) return 0;
54 disk_secno = hpfs_bplus_lookup(inode->i_sb, inode, &fnode->btree, file_secno, bh);
55 if (disk_secno == -1) return 0;
56 if (hpfs_chk_sectors(inode->i_sb, disk_secno, 1, "bmap")) return 0;
57 n = file_secno - hpfs_inode->i_file_sec;
58 if (n < hpfs_inode->i_n_secs) {
59 *n_secs = hpfs_inode->i_n_secs - n;
60 return hpfs_inode->i_disk_sec + n;
61 }
62 *n_secs = 1;
63 return disk_secno;
64 }
65
hpfs_truncate(struct inode * i)66 void hpfs_truncate(struct inode *i)
67 {
68 if (IS_IMMUTABLE(i)) return /*-EPERM*/;
69 hpfs_lock_assert(i->i_sb);
70
71 hpfs_i(i)->i_n_secs = 0;
72 i->i_blocks = 1 + ((i->i_size + 511) >> 9);
73 hpfs_i(i)->mmu_private = i->i_size;
74 hpfs_truncate_btree(i->i_sb, i->i_ino, 1, ((i->i_size + 511) >> 9));
75 hpfs_write_inode(i);
76 hpfs_i(i)->i_n_secs = 0;
77 }
78
hpfs_get_block(struct inode * inode,sector_t iblock,struct buffer_head * bh_result,int create)79 static int hpfs_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
80 {
81 int r;
82 secno s;
83 unsigned n_secs;
84 hpfs_lock(inode->i_sb);
85 s = hpfs_bmap(inode, iblock, &n_secs);
86 if (s) {
87 if (bh_result->b_size >> 9 < n_secs)
88 n_secs = bh_result->b_size >> 9;
89 n_secs = hpfs_search_hotfix_map_for_range(inode->i_sb, s, n_secs);
90 if (unlikely(!n_secs)) {
91 s = hpfs_search_hotfix_map(inode->i_sb, s);
92 n_secs = 1;
93 }
94 map_bh(bh_result, inode->i_sb, s);
95 bh_result->b_size = n_secs << 9;
96 goto ret_0;
97 }
98 if (!create) goto ret_0;
99 if (iblock<<9 != hpfs_i(inode)->mmu_private) {
100 BUG();
101 r = -EIO;
102 goto ret_r;
103 }
104 if ((s = hpfs_add_sector_to_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1)) == -1) {
105 hpfs_truncate_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1);
106 r = -ENOSPC;
107 goto ret_r;
108 }
109 inode->i_blocks++;
110 hpfs_i(inode)->mmu_private += 512;
111 set_buffer_new(bh_result);
112 map_bh(bh_result, inode->i_sb, hpfs_search_hotfix_map(inode->i_sb, s));
113 ret_0:
114 r = 0;
115 ret_r:
116 hpfs_unlock(inode->i_sb);
117 return r;
118 }
119
hpfs_iomap_begin(struct inode * inode,loff_t offset,loff_t length,unsigned flags,struct iomap * iomap,struct iomap * srcmap)120 static int hpfs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
121 unsigned flags, struct iomap *iomap, struct iomap *srcmap)
122 {
123 struct super_block *sb = inode->i_sb;
124 unsigned int blkbits = inode->i_blkbits;
125 unsigned int n_secs;
126 secno s;
127
128 if (WARN_ON_ONCE(flags & (IOMAP_WRITE | IOMAP_ZERO)))
129 return -EINVAL;
130
131 iomap->bdev = inode->i_sb->s_bdev;
132 iomap->offset = offset;
133
134 hpfs_lock(sb);
135 s = hpfs_bmap(inode, offset >> blkbits, &n_secs);
136 if (s) {
137 n_secs = hpfs_search_hotfix_map_for_range(sb, s,
138 min_t(loff_t, n_secs, length));
139 if (unlikely(!n_secs)) {
140 s = hpfs_search_hotfix_map(sb, s);
141 n_secs = 1;
142 }
143 iomap->type = IOMAP_MAPPED;
144 iomap->flags = IOMAP_F_MERGED;
145 iomap->addr = (u64)s << blkbits;
146 iomap->length = (u64)n_secs << blkbits;
147 } else {
148 iomap->type = IOMAP_HOLE;
149 iomap->addr = IOMAP_NULL_ADDR;
150 iomap->length = 1 << blkbits;
151 }
152
153 hpfs_unlock(sb);
154 return 0;
155 }
156
157 static const struct iomap_ops hpfs_iomap_ops = {
158 .iomap_begin = hpfs_iomap_begin,
159 };
160
hpfs_read_folio(struct file * file,struct folio * folio)161 static int hpfs_read_folio(struct file *file, struct folio *folio)
162 {
163 return mpage_read_folio(folio, hpfs_get_block);
164 }
165
hpfs_readahead(struct readahead_control * rac)166 static void hpfs_readahead(struct readahead_control *rac)
167 {
168 mpage_readahead(rac, hpfs_get_block);
169 }
170
hpfs_writepages(struct address_space * mapping,struct writeback_control * wbc)171 static int hpfs_writepages(struct address_space *mapping,
172 struct writeback_control *wbc)
173 {
174 return mpage_writepages(mapping, wbc, hpfs_get_block);
175 }
176
hpfs_write_failed(struct address_space * mapping,loff_t to)177 static void hpfs_write_failed(struct address_space *mapping, loff_t to)
178 {
179 struct inode *inode = mapping->host;
180
181 hpfs_lock(inode->i_sb);
182
183 if (to > inode->i_size) {
184 truncate_pagecache(inode, inode->i_size);
185 hpfs_truncate(inode);
186 }
187
188 hpfs_unlock(inode->i_sb);
189 }
190
hpfs_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,struct page ** pagep,void ** fsdata)191 static int hpfs_write_begin(struct file *file, struct address_space *mapping,
192 loff_t pos, unsigned len,
193 struct page **pagep, void **fsdata)
194 {
195 int ret;
196
197 *pagep = NULL;
198 ret = cont_write_begin(file, mapping, pos, len, pagep, fsdata,
199 hpfs_get_block,
200 &hpfs_i(mapping->host)->mmu_private);
201 if (unlikely(ret))
202 hpfs_write_failed(mapping, pos + len);
203
204 return ret;
205 }
206
hpfs_write_end(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned copied,struct page * pagep,void * fsdata)207 static int hpfs_write_end(struct file *file, struct address_space *mapping,
208 loff_t pos, unsigned len, unsigned copied,
209 struct page *pagep, void *fsdata)
210 {
211 struct inode *inode = mapping->host;
212 int err;
213 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
214 if (err < len)
215 hpfs_write_failed(mapping, pos + len);
216 if (!(err < 0)) {
217 /* make sure we write it on close, if not earlier */
218 hpfs_lock(inode->i_sb);
219 hpfs_i(inode)->i_dirty = 1;
220 hpfs_unlock(inode->i_sb);
221 }
222 return err;
223 }
224
_hpfs_bmap(struct address_space * mapping,sector_t block)225 static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
226 {
227 return generic_block_bmap(mapping, block, hpfs_get_block);
228 }
229
hpfs_fiemap(struct inode * inode,struct fiemap_extent_info * fieinfo,u64 start,u64 len)230 static int hpfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 len)
231 {
232 int ret;
233
234 inode_lock(inode);
235 len = min_t(u64, len, i_size_read(inode));
236 ret = iomap_fiemap(inode, fieinfo, start, len, &hpfs_iomap_ops);
237 inode_unlock(inode);
238
239 return ret;
240 }
241
242 const struct address_space_operations hpfs_aops = {
243 .dirty_folio = block_dirty_folio,
244 .invalidate_folio = block_invalidate_folio,
245 .read_folio = hpfs_read_folio,
246 .readahead = hpfs_readahead,
247 .writepages = hpfs_writepages,
248 .write_begin = hpfs_write_begin,
249 .write_end = hpfs_write_end,
250 .bmap = _hpfs_bmap,
251 .migrate_folio = buffer_migrate_folio,
252 };
253
254 const struct file_operations hpfs_file_ops =
255 {
256 .llseek = generic_file_llseek,
257 .read_iter = generic_file_read_iter,
258 .write_iter = generic_file_write_iter,
259 .mmap = generic_file_mmap,
260 .release = hpfs_file_release,
261 .fsync = hpfs_file_fsync,
262 .splice_read = filemap_splice_read,
263 .unlocked_ioctl = hpfs_ioctl,
264 .compat_ioctl = compat_ptr_ioctl,
265 };
266
267 const struct inode_operations hpfs_file_iops =
268 {
269 .setattr = hpfs_setattr,
270 .fiemap = hpfs_fiemap,
271 };
272