Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux...
[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 #include <linux/smp_lock.h>
41
42 #include "udf_i.h"
43 #include "udf_sb.h"
44
45 static int udf_adinicb_readpage(struct file *file, struct page *page)
46 {
47         struct inode *inode = page->mapping->host;
48         char *kaddr;
49         struct udf_inode_info *iinfo = UDF_I(inode);
50
51         BUG_ON(!PageLocked(page));
52
53         kaddr = kmap(page);
54         memset(kaddr, 0, PAGE_CACHE_SIZE);
55         memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size);
56         flush_dcache_page(page);
57         SetPageUptodate(page);
58         kunmap(page);
59         unlock_page(page);
60
61         return 0;
62 }
63
64 static 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
83 static int udf_adinicb_write_end(struct file *file,
84                         struct address_space *mapping,
85                         loff_t pos, unsigned len, unsigned copied,
86                         struct page *page, void *fsdata)
87 {
88         struct inode *inode = mapping->host;
89         unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
90         char *kaddr;
91         struct udf_inode_info *iinfo = UDF_I(inode);
92
93         kaddr = kmap_atomic(page, KM_USER0);
94         memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr + offset,
95                 kaddr + offset, copied);
96         kunmap_atomic(kaddr, KM_USER0);
97
98         return simple_write_end(file, mapping, pos, len, copied, page, fsdata);
99 }
100
101 const struct address_space_operations udf_adinicb_aops = {
102         .readpage       = udf_adinicb_readpage,
103         .writepage      = udf_adinicb_writepage,
104         .sync_page      = block_sync_page,
105         .write_begin = simple_write_begin,
106         .write_end = udf_adinicb_write_end,
107 };
108
109 static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
110                                   unsigned long nr_segs, loff_t ppos)
111 {
112         ssize_t retval;
113         struct file *file = iocb->ki_filp;
114         struct inode *inode = file->f_path.dentry->d_inode;
115         int err, pos;
116         size_t count = iocb->ki_left;
117         struct udf_inode_info *iinfo = UDF_I(inode);
118
119         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
120                 if (file->f_flags & O_APPEND)
121                         pos = inode->i_size;
122                 else
123                         pos = ppos;
124
125                 if (inode->i_sb->s_blocksize <
126                                 (udf_file_entry_alloc_offset(inode) +
127                                                 pos + count)) {
128                         udf_expand_file_adinicb(inode, pos + count, &err);
129                         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
130                                 udf_debug("udf_expand_adinicb: err=%d\n", err);
131                                 return err;
132                         }
133                 } else {
134                         if (pos + count > inode->i_size)
135                                 iinfo->i_lenAlloc = pos + count;
136                         else
137                                 iinfo->i_lenAlloc = inode->i_size;
138                 }
139         }
140
141         retval = generic_file_aio_write(iocb, iov, nr_segs, ppos);
142         if (retval > 0)
143                 mark_inode_dirty(inode);
144
145         return retval;
146 }
147
148 long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
149 {
150         struct inode *inode = filp->f_dentry->d_inode;
151         long old_block, new_block;
152         int result = -EINVAL;
153
154         lock_kernel();
155
156         if (file_permission(filp, MAY_READ) != 0) {
157                 udf_debug("no permission to access inode %lu\n", inode->i_ino);
158                 result = -EPERM;
159                 goto out;
160         }
161
162         if (!arg) {
163                 udf_debug("invalid argument to udf_ioctl\n");
164                 result = -EINVAL;
165                 goto out;
166         }
167
168         switch (cmd) {
169         case UDF_GETVOLIDENT:
170                 if (copy_to_user((char __user *)arg,
171                                  UDF_SB(inode->i_sb)->s_volume_ident, 32))
172                         result = -EFAULT;
173                 else
174                         result = 0;
175                 goto out;
176         case UDF_RELOCATE_BLOCKS:
177                 if (!capable(CAP_SYS_ADMIN)) {
178                         result = -EACCES;
179                         goto out;
180                 }
181                 if (get_user(old_block, (long __user *)arg)) {
182                         result = -EFAULT;
183                         goto out;
184                 }
185                 result = udf_relocate_blocks(inode->i_sb,
186                                                 old_block, &new_block);
187                 if (result == 0)
188                         result = put_user(new_block, (long __user *)arg);
189                 goto out;
190         case UDF_GETEASIZE:
191                 result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
192                 goto out;
193         case UDF_GETEABLOCK:
194                 result = copy_to_user((char __user *)arg,
195                                       UDF_I(inode)->i_ext.i_data,
196                                       UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
197                 goto out;
198         }
199
200 out:
201         unlock_kernel();
202         return result;
203 }
204
205 static int udf_release_file(struct inode *inode, struct file *filp)
206 {
207         if (filp->f_mode & FMODE_WRITE) {
208                 mutex_lock(&inode->i_mutex);
209                 lock_kernel();
210                 udf_discard_prealloc(inode);
211                 udf_truncate_tail_extent(inode);
212                 unlock_kernel();
213                 mutex_unlock(&inode->i_mutex);
214         }
215         return 0;
216 }
217
218 const struct file_operations udf_file_operations = {
219         .read                   = do_sync_read,
220         .aio_read               = generic_file_aio_read,
221         .unlocked_ioctl         = udf_ioctl,
222         .open                   = dquot_file_open,
223         .mmap                   = generic_file_mmap,
224         .write                  = do_sync_write,
225         .aio_write              = udf_file_aio_write,
226         .release                = udf_release_file,
227         .fsync                  = simple_fsync,
228         .splice_read            = generic_file_splice_read,
229         .llseek                 = generic_file_llseek,
230 };
231
232 int udf_setattr(struct dentry *dentry, struct iattr *iattr)
233 {
234         struct inode *inode = dentry->d_inode;
235         int error;
236
237         error = inode_change_ok(inode, iattr);
238         if (error)
239                 return error;
240
241         if (is_quota_modification(inode, iattr))
242                 dquot_initialize(inode);
243
244         if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) ||
245             (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) {
246                 error = dquot_transfer(inode, iattr);
247                 if (error)
248                         return error;
249         }
250
251         return inode_setattr(inode, iattr);
252 }
253
254 const struct inode_operations udf_file_inode_operations = {
255         .truncate               = udf_truncate,
256         .setattr                = udf_setattr,
257 };