Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * file.c
4 *
5 * PURPOSE
6 * File handling routines for the OSTA-UDF(tm) filesystem.
7 *
8 * COPYRIGHT
9 * (C) 1998-1999 Dave Boynton
10 * (C) 1998-2004 Ben Fennema
11 * (C) 1999-2000 Stelias Computing Inc
12 *
13 * HISTORY
14 *
15 * 10/02/98 dgb Attempt to integrate into udf.o
16 * 10/07/98 Switched to using generic_readpage, etc., like isofs
17 * And it works!
18 * 12/06/98 blf Added udf_file_read. uses generic_file_read for all cases but
19 * ICBTAG_FLAG_AD_IN_ICB.
20 * 04/06/99 64 bit file handling on 32 bit systems taken from ext2 file.c
21 * 05/12/99 Preliminary file write support
22 */
23
24#include "udfdecl.h"
25#include <linux/fs.h>
26#include <linux/uaccess.h>
27#include <linux/kernel.h>
28#include <linux/string.h> /* memset */
29#include <linux/capability.h>
30#include <linux/errno.h>
31#include <linux/pagemap.h>
32#include <linux/uio.h>
33
34#include "udf_i.h"
35#include "udf_sb.h"
36
37static vm_fault_t udf_page_mkwrite(struct vm_fault *vmf)
38{
39 struct vm_area_struct *vma = vmf->vma;
40 struct inode *inode = file_inode(vma->vm_file);
41 struct address_space *mapping = inode->i_mapping;
42 struct folio *folio = page_folio(vmf->page);
43 loff_t size;
44 unsigned int end;
45 vm_fault_t ret = VM_FAULT_LOCKED;
46 int err;
47
48 sb_start_pagefault(inode->i_sb);
49 file_update_time(vma->vm_file);
50 filemap_invalidate_lock_shared(mapping);
51 folio_lock(folio);
52 size = i_size_read(inode);
53 if (folio->mapping != inode->i_mapping || folio_pos(folio) >= size) {
54 folio_unlock(folio);
55 ret = VM_FAULT_NOPAGE;
56 goto out_unlock;
57 }
58 /* Space is already allocated for in-ICB file */
59 if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
60 goto out_dirty;
61 if (folio->index == size >> PAGE_SHIFT)
62 end = size & ~PAGE_MASK;
63 else
64 end = PAGE_SIZE;
65 err = __block_write_begin(folio, 0, end, udf_get_block);
66 if (err) {
67 folio_unlock(folio);
68 ret = vmf_fs_error(err);
69 goto out_unlock;
70 }
71
72 block_commit_write(&folio->page, 0, end);
73out_dirty:
74 folio_mark_dirty(folio);
75 folio_wait_stable(folio);
76out_unlock:
77 filemap_invalidate_unlock_shared(mapping);
78 sb_end_pagefault(inode->i_sb);
79 return ret;
80}
81
82static const struct vm_operations_struct udf_file_vm_ops = {
83 .fault = filemap_fault,
84 .map_pages = filemap_map_pages,
85 .page_mkwrite = udf_page_mkwrite,
86};
87
88static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
89{
90 ssize_t retval;
91 struct file *file = iocb->ki_filp;
92 struct inode *inode = file_inode(file);
93 struct udf_inode_info *iinfo = UDF_I(inode);
94
95 inode_lock(inode);
96
97 retval = generic_write_checks(iocb, from);
98 if (retval <= 0)
99 goto out;
100
101 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&
102 inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) +
103 iocb->ki_pos + iov_iter_count(from))) {
104 filemap_invalidate_lock(inode->i_mapping);
105 retval = udf_expand_file_adinicb(inode);
106 filemap_invalidate_unlock(inode->i_mapping);
107 if (retval)
108 goto out;
109 }
110
111 retval = __generic_file_write_iter(iocb, from);
112out:
113 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB && retval > 0) {
114 down_write(&iinfo->i_data_sem);
115 iinfo->i_lenAlloc = inode->i_size;
116 up_write(&iinfo->i_data_sem);
117 }
118 inode_unlock(inode);
119
120 if (retval > 0) {
121 mark_inode_dirty(inode);
122 retval = generic_write_sync(iocb, retval);
123 }
124
125 return retval;
126}
127
128long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
129{
130 struct inode *inode = file_inode(filp);
131 long old_block, new_block;
132 int result;
133
134 if (file_permission(filp, MAY_READ) != 0) {
135 udf_debug("no permission to access inode %lu\n", inode->i_ino);
136 return -EPERM;
137 }
138
139 if (!arg && ((cmd == UDF_GETVOLIDENT) || (cmd == UDF_GETEASIZE) ||
140 (cmd == UDF_RELOCATE_BLOCKS) || (cmd == UDF_GETEABLOCK))) {
141 udf_debug("invalid argument to udf_ioctl\n");
142 return -EINVAL;
143 }
144
145 switch (cmd) {
146 case UDF_GETVOLIDENT:
147 if (copy_to_user((char __user *)arg,
148 UDF_SB(inode->i_sb)->s_volume_ident, 32))
149 return -EFAULT;
150 return 0;
151 case UDF_RELOCATE_BLOCKS:
152 if (!capable(CAP_SYS_ADMIN))
153 return -EPERM;
154 if (get_user(old_block, (long __user *)arg))
155 return -EFAULT;
156 result = udf_relocate_blocks(inode->i_sb,
157 old_block, &new_block);
158 if (result == 0)
159 result = put_user(new_block, (long __user *)arg);
160 return result;
161 case UDF_GETEASIZE:
162 return put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
163 case UDF_GETEABLOCK:
164 return copy_to_user((char __user *)arg,
165 UDF_I(inode)->i_data,
166 UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
167 default:
168 return -ENOIOCTLCMD;
169 }
170
171 return 0;
172}
173
174static int udf_release_file(struct inode *inode, struct file *filp)
175{
176 if (filp->f_mode & FMODE_WRITE &&
177 atomic_read(&inode->i_writecount) == 1) {
178 /*
179 * Grab i_mutex to avoid races with writes changing i_size
180 * while we are running.
181 */
182 inode_lock(inode);
183 down_write(&UDF_I(inode)->i_data_sem);
184 udf_discard_prealloc(inode);
185 udf_truncate_tail_extent(inode);
186 up_write(&UDF_I(inode)->i_data_sem);
187 inode_unlock(inode);
188 }
189 return 0;
190}
191
192static int udf_file_mmap(struct file *file, struct vm_area_struct *vma)
193{
194 file_accessed(file);
195 vma->vm_ops = &udf_file_vm_ops;
196
197 return 0;
198}
199
200const struct file_operations udf_file_operations = {
201 .read_iter = generic_file_read_iter,
202 .unlocked_ioctl = udf_ioctl,
203 .open = generic_file_open,
204 .mmap = udf_file_mmap,
205 .write_iter = udf_file_write_iter,
206 .release = udf_release_file,
207 .fsync = generic_file_fsync,
208 .splice_read = filemap_splice_read,
209 .splice_write = iter_file_splice_write,
210 .llseek = generic_file_llseek,
211};
212
213static int udf_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
214 struct iattr *attr)
215{
216 struct inode *inode = d_inode(dentry);
217 struct super_block *sb = inode->i_sb;
218 int error;
219
220 error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
221 if (error)
222 return error;
223
224 if ((attr->ia_valid & ATTR_UID) &&
225 UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET) &&
226 !uid_eq(attr->ia_uid, UDF_SB(sb)->s_uid))
227 return -EPERM;
228 if ((attr->ia_valid & ATTR_GID) &&
229 UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET) &&
230 !gid_eq(attr->ia_gid, UDF_SB(sb)->s_gid))
231 return -EPERM;
232
233 if ((attr->ia_valid & ATTR_SIZE) &&
234 attr->ia_size != i_size_read(inode)) {
235 filemap_invalidate_lock(inode->i_mapping);
236 error = udf_setsize(inode, attr->ia_size);
237 filemap_invalidate_unlock(inode->i_mapping);
238 if (error)
239 return error;
240 }
241
242 if (attr->ia_valid & ATTR_MODE)
243 udf_update_extra_perms(inode, attr->ia_mode);
244
245 setattr_copy(&nop_mnt_idmap, inode, attr);
246 mark_inode_dirty(inode);
247 return 0;
248}
249
250const struct inode_operations udf_file_inode_operations = {
251 .setattr = udf_setattr,
252};
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};