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 <asm/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/smp_lock.h>
36 #include <linux/pagemap.h>
37 #include <linux/buffer_head.h>
38 #include <linux/aio.h>
39
40 #include "udf_i.h"
41 #include "udf_sb.h"
42
43 static int udf_adinicb_readpage(struct file *file, struct page *page)
44 {
45 struct inode *inode = page->mapping->host;
46 char *kaddr;
47 struct udf_inode_info *iinfo = UDF_I(inode);
48
49 BUG_ON(!PageLocked(page));
50
51 kaddr = kmap(page);
52 memset(kaddr, 0, PAGE_CACHE_SIZE);
53 memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size);
54 flush_dcache_page(page);
55 SetPageUptodate(page);
56 kunmap(page);
57 unlock_page(page);
58
59 return 0;
60 }
61
62 static int udf_adinicb_writepage(struct page *page,
63 struct writeback_control *wbc)
64 {
65 struct inode *inode = page->mapping->host;
66 char *kaddr;
67 struct udf_inode_info *iinfo = UDF_I(inode);
68
69 BUG_ON(!PageLocked(page));
70
71 kaddr = kmap(page);
72 memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size);
73 mark_inode_dirty(inode);
74 SetPageUptodate(page);
75 kunmap(page);
76 unlock_page(page);
77
78 return 0;
79 }
80
81 static int udf_adinicb_write_end(struct file *file,
82 struct address_space *mapping,
83 loff_t pos, unsigned len, unsigned copied,
84 struct page *page, void *fsdata)
85 {
86 struct inode *inode = mapping->host;
87 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
88 char *kaddr;
89 struct udf_inode_info *iinfo = UDF_I(inode);
90
91 kaddr = kmap_atomic(page, KM_USER0);
92 memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr + offset,
93 kaddr + offset, copied);
94 kunmap_atomic(kaddr, KM_USER0);
95
96 return simple_write_end(file, mapping, pos, len, copied, page, fsdata);
97 }
98
99 const struct address_space_operations udf_adinicb_aops = {
100 .readpage = udf_adinicb_readpage,
101 .writepage = udf_adinicb_writepage,
102 .sync_page = block_sync_page,
103 .write_begin = simple_write_begin,
104 .write_end = udf_adinicb_write_end,
105 };
106
107 static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
108 unsigned long nr_segs, loff_t ppos)
109 {
110 ssize_t retval;
111 struct file *file = iocb->ki_filp;
112 struct inode *inode = file->f_path.dentry->d_inode;
113 int err, pos;
114 size_t count = iocb->ki_left;
115 struct udf_inode_info *iinfo = UDF_I(inode);
116
117 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
118 if (file->f_flags & O_APPEND)
119 pos = inode->i_size;
120 else
121 pos = ppos;
122
123 if (inode->i_sb->s_blocksize <
124 (udf_file_entry_alloc_offset(inode) +
125 pos + count)) {
126 udf_expand_file_adinicb(inode, pos + count, &err);
127 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
128 udf_debug("udf_expand_adinicb: err=%d\n", err);
129 return err;
130 }
131 } else {
132 if (pos + count > inode->i_size)
133 iinfo->i_lenAlloc = pos + count;
134 else
135 iinfo->i_lenAlloc = inode->i_size;
136 }
137 }
138
139 retval = generic_file_aio_write(iocb, iov, nr_segs, ppos);
140 if (retval > 0)
141 mark_inode_dirty(inode);
142
143 return retval;
144 }
145
146 int udf_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
147 unsigned long arg)
148 {
149 long old_block, new_block;
150 int result = -EINVAL;
151
152 if (file_permission(filp, MAY_READ) != 0) {
153 udf_debug("no permission to access inode %lu\n",
154 inode->i_ino);
155 return -EPERM;
156 }
157
158 if (!arg) {
159 udf_debug("invalid argument to udf_ioctl\n");
160 return -EINVAL;
161 }
162
163 switch (cmd) {
164 case UDF_GETVOLIDENT:
165 if (copy_to_user((char __user *)arg,
166 UDF_SB(inode->i_sb)->s_volume_ident, 32))
167 return -EFAULT;
168 else
169 return 0;
170 case UDF_RELOCATE_BLOCKS:
171 if (!capable(CAP_SYS_ADMIN))
172 return -EACCES;
173 if (get_user(old_block, (long __user *)arg))
174 return -EFAULT;
175 result = udf_relocate_blocks(inode->i_sb,
176 old_block, &new_block);
177 if (result == 0)
178 result = put_user(new_block, (long __user *)arg);
179 return result;
180 case UDF_GETEASIZE:
181 result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
182 break;
183 case UDF_GETEABLOCK:
184 result = copy_to_user((char __user *)arg,
185 UDF_I(inode)->i_ext.i_data,
186 UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
187 break;
188 }
189
190 return result;
191 }
192
193 static int udf_release_file(struct inode *inode, struct file *filp)
194 {
195 if (filp->f_mode & FMODE_WRITE) {
196 lock_kernel();
197 udf_discard_prealloc(inode);
198 unlock_kernel();
199 }
200 return 0;
201 }
202
203 const struct file_operations udf_file_operations = {
204 .read = do_sync_read,
205 .aio_read = generic_file_aio_read,
206 .ioctl = udf_ioctl,
207 .open = generic_file_open,
208 .mmap = generic_file_mmap,
209 .write = do_sync_write,
210 .aio_write = udf_file_aio_write,
211 .release = udf_release_file,
212 .fsync = simple_fsync,
213 .splice_read = generic_file_splice_read,
214 .llseek = generic_file_llseek,
215 };
216
217 const struct inode_operations udf_file_inode_operations = {
218 .truncate = udf_truncate,
219 };
220
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