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1/*
2 * file.c
3 *
4 * PURPOSE
5 * File handling routines for the OSTA-UDF(tm) filesystem.
6 *
7 * COPYRIGHT
8 * This file is distributed under the terms of the GNU General Public
9 * License (GPL). Copies of the GPL can be obtained from:
10 * ftp://prep.ai.mit.edu/pub/gnu/GPL
11 * Each contributing author retains all rights to their own work.
12 *
13 * (C) 1998-1999 Dave Boynton
14 * (C) 1998-2004 Ben Fennema
15 * (C) 1999-2000 Stelias Computing Inc
16 *
17 * HISTORY
18 *
19 * 10/02/98 dgb Attempt to integrate into udf.o
20 * 10/07/98 Switched to using generic_readpage, etc., like isofs
21 * And it works!
22 * 12/06/98 blf Added udf_file_read. uses generic_file_read for all cases but
23 * ICBTAG_FLAG_AD_IN_ICB.
24 * 04/06/99 64 bit file handling on 32 bit systems taken from ext2 file.c
25 * 05/12/99 Preliminary file write support
26 */
27
28#include "udfdecl.h"
29#include <linux/fs.h>
30#include <linux/uaccess.h>
31#include <linux/kernel.h>
32#include <linux/string.h> /* memset */
33#include <linux/capability.h>
34#include <linux/errno.h>
35#include <linux/pagemap.h>
36#include <linux/uio.h>
37
38#include "udf_i.h"
39#include "udf_sb.h"
40
41static void __udf_adinicb_readpage(struct page *page)
42{
43 struct inode *inode = page->mapping->host;
44 char *kaddr;
45 struct udf_inode_info *iinfo = UDF_I(inode);
46 loff_t isize = i_size_read(inode);
47
48 /*
49 * We have to be careful here as truncate can change i_size under us.
50 * So just sample it once and use the same value everywhere.
51 */
52 kaddr = kmap_atomic(page);
53 memcpy(kaddr, iinfo->i_data + iinfo->i_lenEAttr, isize);
54 memset(kaddr + isize, 0, PAGE_SIZE - isize);
55 flush_dcache_page(page);
56 SetPageUptodate(page);
57 kunmap_atomic(kaddr);
58}
59
60static int udf_adinicb_read_folio(struct file *file, struct folio *folio)
61{
62 BUG_ON(!folio_test_locked(folio));
63 __udf_adinicb_readpage(&folio->page);
64 folio_unlock(folio);
65
66 return 0;
67}
68
69static int udf_adinicb_writepage(struct page *page,
70 struct writeback_control *wbc)
71{
72 struct inode *inode = page->mapping->host;
73 char *kaddr;
74 struct udf_inode_info *iinfo = UDF_I(inode);
75
76 BUG_ON(!PageLocked(page));
77
78 kaddr = kmap_atomic(page);
79 memcpy(iinfo->i_data + iinfo->i_lenEAttr, kaddr, i_size_read(inode));
80 SetPageUptodate(page);
81 kunmap_atomic(kaddr);
82 mark_inode_dirty(inode);
83 unlock_page(page);
84
85 return 0;
86}
87
88static int udf_adinicb_write_begin(struct file *file,
89 struct address_space *mapping, loff_t pos,
90 unsigned len, struct page **pagep,
91 void **fsdata)
92{
93 struct page *page;
94
95 if (WARN_ON_ONCE(pos >= PAGE_SIZE))
96 return -EIO;
97 page = grab_cache_page_write_begin(mapping, 0);
98 if (!page)
99 return -ENOMEM;
100 *pagep = page;
101
102 if (!PageUptodate(page))
103 __udf_adinicb_readpage(page);
104 return 0;
105}
106
107static ssize_t udf_adinicb_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
108{
109 /* Fallback to buffered I/O. */
110 return 0;
111}
112
113static int udf_adinicb_write_end(struct file *file, struct address_space *mapping,
114 loff_t pos, unsigned len, unsigned copied,
115 struct page *page, void *fsdata)
116{
117 struct inode *inode = page->mapping->host;
118 loff_t last_pos = pos + copied;
119 if (last_pos > inode->i_size)
120 i_size_write(inode, last_pos);
121 set_page_dirty(page);
122 unlock_page(page);
123 put_page(page);
124 return copied;
125}
126
127const struct address_space_operations udf_adinicb_aops = {
128 .dirty_folio = block_dirty_folio,
129 .invalidate_folio = block_invalidate_folio,
130 .read_folio = udf_adinicb_read_folio,
131 .writepage = udf_adinicb_writepage,
132 .write_begin = udf_adinicb_write_begin,
133 .write_end = udf_adinicb_write_end,
134 .direct_IO = udf_adinicb_direct_IO,
135};
136
137static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
138{
139 ssize_t retval;
140 struct file *file = iocb->ki_filp;
141 struct inode *inode = file_inode(file);
142 struct udf_inode_info *iinfo = UDF_I(inode);
143 int err;
144
145 inode_lock(inode);
146
147 retval = generic_write_checks(iocb, from);
148 if (retval <= 0)
149 goto out;
150
151 down_write(&iinfo->i_data_sem);
152 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
153 loff_t end = iocb->ki_pos + iov_iter_count(from);
154
155 if (inode->i_sb->s_blocksize <
156 (udf_file_entry_alloc_offset(inode) + end)) {
157 err = udf_expand_file_adinicb(inode);
158 if (err) {
159 inode_unlock(inode);
160 udf_debug("udf_expand_adinicb: err=%d\n", err);
161 return err;
162 }
163 } else {
164 iinfo->i_lenAlloc = max(end, inode->i_size);
165 up_write(&iinfo->i_data_sem);
166 }
167 } else
168 up_write(&iinfo->i_data_sem);
169
170 retval = __generic_file_write_iter(iocb, from);
171out:
172 inode_unlock(inode);
173
174 if (retval > 0) {
175 mark_inode_dirty(inode);
176 retval = generic_write_sync(iocb, retval);
177 }
178
179 return retval;
180}
181
182long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
183{
184 struct inode *inode = file_inode(filp);
185 long old_block, new_block;
186 int result;
187
188 if (file_permission(filp, MAY_READ) != 0) {
189 udf_debug("no permission to access inode %lu\n", inode->i_ino);
190 return -EPERM;
191 }
192
193 if (!arg && ((cmd == UDF_GETVOLIDENT) || (cmd == UDF_GETEASIZE) ||
194 (cmd == UDF_RELOCATE_BLOCKS) || (cmd == UDF_GETEABLOCK))) {
195 udf_debug("invalid argument to udf_ioctl\n");
196 return -EINVAL;
197 }
198
199 switch (cmd) {
200 case UDF_GETVOLIDENT:
201 if (copy_to_user((char __user *)arg,
202 UDF_SB(inode->i_sb)->s_volume_ident, 32))
203 return -EFAULT;
204 return 0;
205 case UDF_RELOCATE_BLOCKS:
206 if (!capable(CAP_SYS_ADMIN))
207 return -EPERM;
208 if (get_user(old_block, (long __user *)arg))
209 return -EFAULT;
210 result = udf_relocate_blocks(inode->i_sb,
211 old_block, &new_block);
212 if (result == 0)
213 result = put_user(new_block, (long __user *)arg);
214 return result;
215 case UDF_GETEASIZE:
216 return put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
217 case UDF_GETEABLOCK:
218 return copy_to_user((char __user *)arg,
219 UDF_I(inode)->i_data,
220 UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
221 default:
222 return -ENOIOCTLCMD;
223 }
224
225 return 0;
226}
227
228static int udf_release_file(struct inode *inode, struct file *filp)
229{
230 if (filp->f_mode & FMODE_WRITE &&
231 atomic_read(&inode->i_writecount) == 1) {
232 /*
233 * Grab i_mutex to avoid races with writes changing i_size
234 * while we are running.
235 */
236 inode_lock(inode);
237 down_write(&UDF_I(inode)->i_data_sem);
238 udf_discard_prealloc(inode);
239 udf_truncate_tail_extent(inode);
240 up_write(&UDF_I(inode)->i_data_sem);
241 inode_unlock(inode);
242 }
243 return 0;
244}
245
246const struct file_operations udf_file_operations = {
247 .read_iter = generic_file_read_iter,
248 .unlocked_ioctl = udf_ioctl,
249 .open = generic_file_open,
250 .mmap = generic_file_mmap,
251 .write_iter = udf_file_write_iter,
252 .release = udf_release_file,
253 .fsync = generic_file_fsync,
254 .splice_read = generic_file_splice_read,
255 .splice_write = iter_file_splice_write,
256 .llseek = generic_file_llseek,
257};
258
259static int udf_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
260 struct iattr *attr)
261{
262 struct inode *inode = d_inode(dentry);
263 struct super_block *sb = inode->i_sb;
264 int error;
265
266 error = setattr_prepare(&init_user_ns, dentry, attr);
267 if (error)
268 return error;
269
270 if ((attr->ia_valid & ATTR_UID) &&
271 UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET) &&
272 !uid_eq(attr->ia_uid, UDF_SB(sb)->s_uid))
273 return -EPERM;
274 if ((attr->ia_valid & ATTR_GID) &&
275 UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET) &&
276 !gid_eq(attr->ia_gid, UDF_SB(sb)->s_gid))
277 return -EPERM;
278
279 if ((attr->ia_valid & ATTR_SIZE) &&
280 attr->ia_size != i_size_read(inode)) {
281 error = udf_setsize(inode, attr->ia_size);
282 if (error)
283 return error;
284 }
285
286 if (attr->ia_valid & ATTR_MODE)
287 udf_update_extra_perms(inode, attr->ia_mode);
288
289 setattr_copy(&init_user_ns, inode, attr);
290 mark_inode_dirty(inode);
291 return 0;
292}
293
294const struct inode_operations udf_file_inode_operations = {
295 .setattr = udf_setattr,
296};
1/*
2 * file.c
3 *
4 * PURPOSE
5 * File handling routines for the OSTA-UDF(tm) filesystem.
6 *
7 * COPYRIGHT
8 * This file is distributed under the terms of the GNU General Public
9 * License (GPL). Copies of the GPL can be obtained from:
10 * ftp://prep.ai.mit.edu/pub/gnu/GPL
11 * Each contributing author retains all rights to their own work.
12 *
13 * (C) 1998-1999 Dave Boynton
14 * (C) 1998-2004 Ben Fennema
15 * (C) 1999-2000 Stelias Computing Inc
16 *
17 * HISTORY
18 *
19 * 10/02/98 dgb Attempt to integrate into udf.o
20 * 10/07/98 Switched to using generic_readpage, etc., like isofs
21 * And it works!
22 * 12/06/98 blf Added udf_file_read. uses generic_file_read for all cases but
23 * ICBTAG_FLAG_AD_IN_ICB.
24 * 04/06/99 64 bit file handling on 32 bit systems taken from ext2 file.c
25 * 05/12/99 Preliminary file write support
26 */
27
28#include "udfdecl.h"
29#include <linux/fs.h>
30#include <linux/uaccess.h>
31#include <linux/kernel.h>
32#include <linux/string.h> /* memset */
33#include <linux/capability.h>
34#include <linux/errno.h>
35#include <linux/pagemap.h>
36#include <linux/uio.h>
37
38#include "udf_i.h"
39#include "udf_sb.h"
40
41static void __udf_adinicb_readpage(struct page *page)
42{
43 struct inode *inode = page->mapping->host;
44 char *kaddr;
45 struct udf_inode_info *iinfo = UDF_I(inode);
46
47 kaddr = kmap(page);
48 memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size);
49 memset(kaddr + inode->i_size, 0, PAGE_SIZE - inode->i_size);
50 flush_dcache_page(page);
51 SetPageUptodate(page);
52 kunmap(page);
53}
54
55static int udf_adinicb_readpage(struct file *file, struct page *page)
56{
57 BUG_ON(!PageLocked(page));
58 __udf_adinicb_readpage(page);
59 unlock_page(page);
60
61 return 0;
62}
63
64static int udf_adinicb_writepage(struct page *page,
65 struct writeback_control *wbc)
66{
67 struct inode *inode = page->mapping->host;
68 char *kaddr;
69 struct udf_inode_info *iinfo = UDF_I(inode);
70
71 BUG_ON(!PageLocked(page));
72
73 kaddr = kmap(page);
74 memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size);
75 mark_inode_dirty(inode);
76 SetPageUptodate(page);
77 kunmap(page);
78 unlock_page(page);
79
80 return 0;
81}
82
83static int udf_adinicb_write_begin(struct file *file,
84 struct address_space *mapping, loff_t pos,
85 unsigned len, unsigned flags, struct page **pagep,
86 void **fsdata)
87{
88 struct page *page;
89
90 if (WARN_ON_ONCE(pos >= PAGE_SIZE))
91 return -EIO;
92 page = grab_cache_page_write_begin(mapping, 0, flags);
93 if (!page)
94 return -ENOMEM;
95 *pagep = page;
96
97 if (!PageUptodate(page) && len != PAGE_SIZE)
98 __udf_adinicb_readpage(page);
99 return 0;
100}
101
102static ssize_t udf_adinicb_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
103 loff_t offset)
104{
105 /* Fallback to buffered I/O. */
106 return 0;
107}
108
109const struct address_space_operations udf_adinicb_aops = {
110 .readpage = udf_adinicb_readpage,
111 .writepage = udf_adinicb_writepage,
112 .write_begin = udf_adinicb_write_begin,
113 .write_end = simple_write_end,
114 .direct_IO = udf_adinicb_direct_IO,
115};
116
117static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
118{
119 ssize_t retval;
120 struct file *file = iocb->ki_filp;
121 struct inode *inode = file_inode(file);
122 struct udf_inode_info *iinfo = UDF_I(inode);
123 int err;
124
125 inode_lock(inode);
126
127 retval = generic_write_checks(iocb, from);
128 if (retval <= 0)
129 goto out;
130
131 down_write(&iinfo->i_data_sem);
132 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
133 loff_t end = iocb->ki_pos + iov_iter_count(from);
134
135 if (inode->i_sb->s_blocksize <
136 (udf_file_entry_alloc_offset(inode) + end)) {
137 err = udf_expand_file_adinicb(inode);
138 if (err) {
139 inode_unlock(inode);
140 udf_debug("udf_expand_adinicb: err=%d\n", err);
141 return err;
142 }
143 } else {
144 iinfo->i_lenAlloc = max(end, inode->i_size);
145 up_write(&iinfo->i_data_sem);
146 }
147 } else
148 up_write(&iinfo->i_data_sem);
149
150 retval = __generic_file_write_iter(iocb, from);
151out:
152 inode_unlock(inode);
153
154 if (retval > 0) {
155 mark_inode_dirty(inode);
156 err = generic_write_sync(file, iocb->ki_pos - retval, retval);
157 if (err < 0)
158 retval = err;
159 }
160
161 return retval;
162}
163
164long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
165{
166 struct inode *inode = file_inode(filp);
167 long old_block, new_block;
168 int result = -EINVAL;
169
170 if (inode_permission(inode, MAY_READ) != 0) {
171 udf_debug("no permission to access inode %lu\n", inode->i_ino);
172 result = -EPERM;
173 goto out;
174 }
175
176 if (!arg) {
177 udf_debug("invalid argument to udf_ioctl\n");
178 result = -EINVAL;
179 goto out;
180 }
181
182 switch (cmd) {
183 case UDF_GETVOLIDENT:
184 if (copy_to_user((char __user *)arg,
185 UDF_SB(inode->i_sb)->s_volume_ident, 32))
186 result = -EFAULT;
187 else
188 result = 0;
189 goto out;
190 case UDF_RELOCATE_BLOCKS:
191 if (!capable(CAP_SYS_ADMIN)) {
192 result = -EPERM;
193 goto out;
194 }
195 if (get_user(old_block, (long __user *)arg)) {
196 result = -EFAULT;
197 goto out;
198 }
199 result = udf_relocate_blocks(inode->i_sb,
200 old_block, &new_block);
201 if (result == 0)
202 result = put_user(new_block, (long __user *)arg);
203 goto out;
204 case UDF_GETEASIZE:
205 result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
206 goto out;
207 case UDF_GETEABLOCK:
208 result = copy_to_user((char __user *)arg,
209 UDF_I(inode)->i_ext.i_data,
210 UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
211 goto out;
212 }
213
214out:
215 return result;
216}
217
218static int udf_release_file(struct inode *inode, struct file *filp)
219{
220 if (filp->f_mode & FMODE_WRITE &&
221 atomic_read(&inode->i_writecount) == 1) {
222 /*
223 * Grab i_mutex to avoid races with writes changing i_size
224 * while we are running.
225 */
226 inode_lock(inode);
227 down_write(&UDF_I(inode)->i_data_sem);
228 udf_discard_prealloc(inode);
229 udf_truncate_tail_extent(inode);
230 up_write(&UDF_I(inode)->i_data_sem);
231 inode_unlock(inode);
232 }
233 return 0;
234}
235
236const struct file_operations udf_file_operations = {
237 .read_iter = generic_file_read_iter,
238 .unlocked_ioctl = udf_ioctl,
239 .open = generic_file_open,
240 .mmap = generic_file_mmap,
241 .write_iter = udf_file_write_iter,
242 .release = udf_release_file,
243 .fsync = generic_file_fsync,
244 .splice_read = generic_file_splice_read,
245 .llseek = generic_file_llseek,
246};
247
248static int udf_setattr(struct dentry *dentry, struct iattr *attr)
249{
250 struct inode *inode = d_inode(dentry);
251 int error;
252
253 error = inode_change_ok(inode, attr);
254 if (error)
255 return error;
256
257 if ((attr->ia_valid & ATTR_SIZE) &&
258 attr->ia_size != i_size_read(inode)) {
259 error = udf_setsize(inode, attr->ia_size);
260 if (error)
261 return error;
262 }
263
264 setattr_copy(inode, attr);
265 mark_inode_dirty(inode);
266 return 0;
267}
268
269const struct inode_operations udf_file_inode_operations = {
270 .setattr = udf_setattr,
271};