Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
[sfrench/cifs-2.6.git] / fs / udf / file.c
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/quotaops.h>
38 #include <linux/buffer_head.h>
39 #include <linux/aio.h>
40
41 #include "udf_i.h"
42 #include "udf_sb.h"
43
44 static int udf_adinicb_readpage(struct file *file, struct page *page)
45 {
46         struct inode *inode = page->mapping->host;
47         char *kaddr;
48         struct udf_inode_info *iinfo = UDF_I(inode);
49
50         BUG_ON(!PageLocked(page));
51
52         kaddr = kmap(page);
53         memset(kaddr, 0, PAGE_CACHE_SIZE);
54         memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size);
55         flush_dcache_page(page);
56         SetPageUptodate(page);
57         kunmap(page);
58         unlock_page(page);
59
60         return 0;
61 }
62
63 static int udf_adinicb_writepage(struct page *page,
64                                  struct writeback_control *wbc)
65 {
66         struct inode *inode = page->mapping->host;
67         char *kaddr;
68         struct udf_inode_info *iinfo = UDF_I(inode);
69
70         BUG_ON(!PageLocked(page));
71
72         kaddr = kmap(page);
73         memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size);
74         mark_inode_dirty(inode);
75         SetPageUptodate(page);
76         kunmap(page);
77         unlock_page(page);
78
79         return 0;
80 }
81
82 static int udf_adinicb_write_end(struct file *file,
83                         struct address_space *mapping,
84                         loff_t pos, unsigned len, unsigned copied,
85                         struct page *page, void *fsdata)
86 {
87         struct inode *inode = mapping->host;
88         unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
89         char *kaddr;
90         struct udf_inode_info *iinfo = UDF_I(inode);
91
92         kaddr = kmap_atomic(page, KM_USER0);
93         memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr + offset,
94                 kaddr + offset, copied);
95         kunmap_atomic(kaddr, KM_USER0);
96
97         return simple_write_end(file, mapping, pos, len, copied, page, fsdata);
98 }
99
100 const struct address_space_operations udf_adinicb_aops = {
101         .readpage       = udf_adinicb_readpage,
102         .writepage      = udf_adinicb_writepage,
103         .sync_page      = block_sync_page,
104         .write_begin = simple_write_begin,
105         .write_end = udf_adinicb_write_end,
106 };
107
108 static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
109                                   unsigned long nr_segs, loff_t ppos)
110 {
111         ssize_t retval;
112         struct file *file = iocb->ki_filp;
113         struct inode *inode = file->f_path.dentry->d_inode;
114         int err, pos;
115         size_t count = iocb->ki_left;
116         struct udf_inode_info *iinfo = UDF_I(inode);
117
118         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
119                 if (file->f_flags & O_APPEND)
120                         pos = inode->i_size;
121                 else
122                         pos = ppos;
123
124                 if (inode->i_sb->s_blocksize <
125                                 (udf_file_entry_alloc_offset(inode) +
126                                                 pos + count)) {
127                         udf_expand_file_adinicb(inode, pos + count, &err);
128                         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
129                                 udf_debug("udf_expand_adinicb: err=%d\n", err);
130                                 return err;
131                         }
132                 } else {
133                         if (pos + count > inode->i_size)
134                                 iinfo->i_lenAlloc = pos + count;
135                         else
136                                 iinfo->i_lenAlloc = inode->i_size;
137                 }
138         }
139
140         retval = generic_file_aio_write(iocb, iov, nr_segs, ppos);
141         if (retval > 0)
142                 mark_inode_dirty(inode);
143
144         return retval;
145 }
146
147 int udf_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
148               unsigned long arg)
149 {
150         long old_block, new_block;
151         int result = -EINVAL;
152
153         if (file_permission(filp, MAY_READ) != 0) {
154                 udf_debug("no permission to access inode %lu\n",
155                           inode->i_ino);
156                 return -EPERM;
157         }
158
159         if (!arg) {
160                 udf_debug("invalid argument to udf_ioctl\n");
161                 return -EINVAL;
162         }
163
164         switch (cmd) {
165         case UDF_GETVOLIDENT:
166                 if (copy_to_user((char __user *)arg,
167                                  UDF_SB(inode->i_sb)->s_volume_ident, 32))
168                         return -EFAULT;
169                 else
170                         return 0;
171         case UDF_RELOCATE_BLOCKS:
172                 if (!capable(CAP_SYS_ADMIN))
173                         return -EACCES;
174                 if (get_user(old_block, (long __user *)arg))
175                         return -EFAULT;
176                 result = udf_relocate_blocks(inode->i_sb,
177                                                 old_block, &new_block);
178                 if (result == 0)
179                         result = put_user(new_block, (long __user *)arg);
180                 return result;
181         case UDF_GETEASIZE:
182                 result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
183                 break;
184         case UDF_GETEABLOCK:
185                 result = copy_to_user((char __user *)arg,
186                                       UDF_I(inode)->i_ext.i_data,
187                                       UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
188                 break;
189         }
190
191         return result;
192 }
193
194 static int udf_release_file(struct inode *inode, struct file *filp)
195 {
196         if (filp->f_mode & FMODE_WRITE) {
197                 mutex_lock(&inode->i_mutex);
198                 lock_kernel();
199                 udf_discard_prealloc(inode);
200                 udf_truncate_tail_extent(inode);
201                 unlock_kernel();
202                 mutex_unlock(&inode->i_mutex);
203         }
204         return 0;
205 }
206
207 const struct file_operations udf_file_operations = {
208         .read                   = do_sync_read,
209         .aio_read               = generic_file_aio_read,
210         .ioctl                  = udf_ioctl,
211         .open                   = dquot_file_open,
212         .mmap                   = generic_file_mmap,
213         .write                  = do_sync_write,
214         .aio_write              = udf_file_aio_write,
215         .release                = udf_release_file,
216         .fsync                  = simple_fsync,
217         .splice_read            = generic_file_splice_read,
218         .llseek                 = generic_file_llseek,
219 };
220
221 static int udf_setattr(struct dentry *dentry, struct iattr *iattr)
222 {
223         struct inode *inode = dentry->d_inode;
224         int error;
225
226         error = inode_change_ok(inode, iattr);
227         if (error)
228                 return error;
229
230         if (iattr->ia_valid & ATTR_SIZE)
231                 dquot_initialize(inode);
232
233         if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) ||
234             (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) {
235                 error = dquot_transfer(inode, iattr);
236                 if (error)
237                         return error;
238         }
239
240         return inode_setattr(inode, iattr);
241 }
242
243 const struct inode_operations udf_file_inode_operations = {
244         .truncate               = udf_truncate,
245         .setattr                = udf_setattr,
246 };