aboutsummaryrefslogtreecommitdiffstats
path: root/fs/udf/file.c
blob: a1e07a13162377a0b961af4ffe3d2ffab110af92 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
/*
 * file.c
 *
 * PURPOSE
 *  File handling routines for the OSTA-UDF(tm) filesystem.
 *
 * COPYRIGHT
 *  This file is distributed under the terms of the GNU General Public
 *  License (GPL). Copies of the GPL can be obtained from:
 *    ftp://prep.ai.mit.edu/pub/gnu/GPL
 *  Each contributing author retains all rights to their own work.
 *
 *  (C) 1998-1999 Dave Boynton
 *  (C) 1998-2004 Ben Fennema
 *  (C) 1999-2000 Stelias Computing Inc
 *
 * HISTORY
 *
 *  10/02/98 dgb  Attempt to integrate into udf.o
 *  10/07/98      Switched to using generic_readpage, etc., like isofs
 *                And it works!
 *  12/06/98 blf  Added udf_file_read. uses generic_file_read for all cases but
 *                ICBTAG_FLAG_AD_IN_ICB.
 *  04/06/99      64 bit file handling on 32 bit systems taken from ext2 file.c
 *  05/12/99      Preliminary file write support
 */

#include "udfdecl.h"
#include <linux/fs.h>
#include <linux/udf_fs.h>
#include <asm/uaccess.h>
#include <linux/kernel.h>
#include <linux/string.h> /* memset */
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/smp_lock.h>
#include <linux/pagemap.h>
#include <linux/buffer_head.h>
#include <linux/aio.h>

#include "udf_i.h"
#include "udf_sb.h"

static int udf_adinicb_readpage(struct file *file, struct page *page)
{
	struct inode *inode = page->mapping->host;
	char *kaddr;

	BUG_ON(!PageLocked(page));

	kaddr = kmap(page);
	memset(kaddr, 0, PAGE_CACHE_SIZE);
	memcpy(kaddr, UDF_I(inode)->i_ext.i_data + UDF_I(inode)->i_lenEAttr,
								inode->i_size);
	flush_dcache_page(page);
	SetPageUptodate(page);
	kunmap(page);
	unlock_page(page);

	return 0;
}

static int udf_adinicb_writepage(struct page *page,
				 struct writeback_control *wbc)
{
	struct inode *inode = page->mapping->host;
	char *kaddr;

	BUG_ON(!PageLocked(page));

	kaddr = kmap(page);
	memcpy(UDF_I(inode)->i_ext.i_data + UDF_I(inode)->i_lenEAttr, kaddr,
								inode->i_size);
	mark_inode_dirty(inode);
	SetPageUptodate(page);
	kunmap(page);
	unlock_page(page);

	return 0;
}

static int udf_adinicb_write_end(struct file *file,
			struct address_space *mapping,
			loff_t pos, unsigned len, unsigned copied,
			struct page *page, void *fsdata)
{
	struct inode *inode = mapping->host;
	unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
	char *kaddr;

	kaddr = kmap_atomic(page, KM_USER0);
	memcpy(UDF_I(inode)->i_ext.i_data + UDF_I(inode)->i_lenEAttr + offset,
		kaddr + offset, copied);
	kunmap_atomic(kaddr, KM_USER0);

	return simple_write_end(file, mapping, pos, len, copied, page, fsdata);
}

const struct address_space_operations udf_adinicb_aops = {
	.readpage	= udf_adinicb_readpage,
	.writepage	= udf_adinicb_writepage,
	.sync_page	= block_sync_page,
	.write_begin = simple_write_begin,
	.write_end = udf_adinicb_write_end,
};

static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
				  unsigned long nr_segs, loff_t ppos)
{
	ssize_t retval;
	struct file *file = iocb->ki_filp;
	struct inode *inode = file->f_path.dentry->d_inode;
	int err, pos;
	size_t count = iocb->ki_left;

	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
		if (file->f_flags & O_APPEND)
			pos = inode->i_size;
		else
			pos = ppos;

		if (inode->i_sb->s_blocksize <
				(udf_file_entry_alloc_offset(inode) +
						pos + count)) {
			udf_expand_file_adinicb(inode, pos + count, &err);
			if (UDF_I(inode)->i_alloc_type ==
							ICBTAG_FLAG_AD_IN_ICB) {
				udf_debug("udf_expand_adinicb: err=%d\n", err);
				return err;
			}
		} else {
			if (pos + count > inode->i_size)
				UDF_I(inode)->i_lenAlloc = pos + count;
			else
				UDF_I(inode)->i_lenAlloc = inode->i_size;
		}
	}

	retval = generic_file_aio_write(iocb, iov, nr_segs, ppos);
	if (retval > 0)
		mark_inode_dirty(inode);

	return retval;
}

/*
 * udf_ioctl
 *
 * PURPOSE
 *	Issue an ioctl.
 *
 * DESCRIPTION
 *	Optional - sys_ioctl() will return -ENOTTY if this routine is not
 *	available, and the ioctl cannot be handled without filesystem help.
 *
 *	sys_ioctl() handles these ioctls that apply only to regular files:
 *		FIBMAP [requires udf_block_map()], FIGETBSZ, FIONREAD
 *	These ioctls are also handled by sys_ioctl():
 *		FIOCLEX, FIONCLEX, FIONBIO, FIOASYNC
 *	All other ioctls are passed to the filesystem.
 *
 *	Refer to sys_ioctl() in fs/ioctl.c
 *	sys_ioctl() -> .
 *
 * PRE-CONDITIONS
 *	inode			Pointer to inode that ioctl was issued on.
 *	filp			Pointer to file that ioctl was issued on.
 *	cmd			The ioctl command.
 *	arg			The ioctl argument [can be interpreted as a
 *				user-space pointer if desired].
 *
 * POST-CONDITIONS
 *	<return>		Success (>=0) or an error code (<=0) that
 *				sys_ioctl() will return.
 *
 * HISTORY
 *	July 1, 1997 - Andrew E. Mileski
 *	Written, tested, and released.
 */
int udf_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
	      unsigned long arg)
{
	long old_block, new_block;
	int result = -EINVAL;

	if (file_permission(filp, MAY_READ) != 0) {
		udf_debug("no permission to access inode %lu\n",
			  inode->i_ino);
		return -EPERM;
	}

	if (!arg) {
		udf_debug("invalid argument to udf_ioctl\n");
		return -EINVAL;
	}

	switch (cmd) {
	case UDF_GETVOLIDENT:
		if (copy_to_user((char __user *)arg,
				 UDF_SB(inode->i_sb)->s_volume_ident, 32))
			return -EFAULT;
		else
			return 0;
	case UDF_RELOCATE_BLOCKS:
		if (!capable(CAP_SYS_ADMIN))
			return -EACCES;
		if (get_user(old_block, (long __user *)arg))
			return -EFAULT;
		result = udf_relocate_blocks(inode->i_sb,
						old_block, &new_block);
		if (result == 0)
			result = put_user(new_block, (long __user *)arg);
		return result;
	case UDF_GETEASIZE:
		result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
		break;
	case UDF_GETEABLOCK:
		result = copy_to_user((char __user *)arg,
				      UDF_I(inode)->i_ext.i_data,
				      UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
		break;
	}

	return result;
}

/*
 * udf_release_file
 *
 * PURPOSE
 *  Called when all references to the file are closed
 *
 * DESCRIPTION
 *  Discard prealloced blocks
 *
 * HISTORY
 *
 */
static int udf_release_file(struct inode *inode, struct file *filp)
{
	if (filp->f_mode & FMODE_WRITE) {
		lock_kernel();
		udf_discard_prealloc(inode);
		unlock_kernel();
	}
	return 0;
}

const struct file_operations udf_file_operations = {
	.read			= do_sync_read,
	.aio_read		= generic_file_aio_read,
	.ioctl			= udf_ioctl,
	.open			= generic_file_open,
	.mmap			= generic_file_mmap,
	.write			= do_sync_write,
	.aio_write		= udf_file_aio_write,
	.release		= udf_release_file,
	.fsync			= udf_fsync_file,
	.splice_read		= generic_file_splice_read,
};

const struct inode_operations udf_file_inode_operations = {
	.truncate = udf_truncate,
};