block: remove per-queue plugging
[linux-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/pagemap.h>
36 #include <linux/buffer_head.h>
37 #include <linux/aio.h>
38
39 #include "udf_i.h"
40 #include "udf_sb.h"
41
42 static int udf_adinicb_readpage(struct file *file, struct page *page)
43 {
44         struct inode *inode = page->mapping->host;
45         char *kaddr;
46         struct udf_inode_info *iinfo = UDF_I(inode);
47
48         BUG_ON(!PageLocked(page));
49
50         kaddr = kmap(page);
51         memset(kaddr, 0, PAGE_CACHE_SIZE);
52         memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size);
53         flush_dcache_page(page);
54         SetPageUptodate(page);
55         kunmap(page);
56         unlock_page(page);
57
58         return 0;
59 }
60
61 static int udf_adinicb_writepage(struct page *page,
62                                  struct writeback_control *wbc)
63 {
64         struct inode *inode = page->mapping->host;
65         char *kaddr;
66         struct udf_inode_info *iinfo = UDF_I(inode);
67
68         BUG_ON(!PageLocked(page));
69
70         kaddr = kmap(page);
71         memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size);
72         mark_inode_dirty(inode);
73         SetPageUptodate(page);
74         kunmap(page);
75         unlock_page(page);
76
77         return 0;
78 }
79
80 static int udf_adinicb_write_end(struct file *file,
81                         struct address_space *mapping,
82                         loff_t pos, unsigned len, unsigned copied,
83                         struct page *page, void *fsdata)
84 {
85         struct inode *inode = mapping->host;
86         unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
87         char *kaddr;
88         struct udf_inode_info *iinfo = UDF_I(inode);
89
90         kaddr = kmap_atomic(page, KM_USER0);
91         memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr + offset,
92                 kaddr + offset, copied);
93         kunmap_atomic(kaddr, KM_USER0);
94
95         return simple_write_end(file, mapping, pos, len, copied, page, fsdata);
96 }
97
98 const struct address_space_operations udf_adinicb_aops = {
99         .readpage       = udf_adinicb_readpage,
100         .writepage      = udf_adinicb_writepage,
101         .write_begin = simple_write_begin,
102         .write_end = udf_adinicb_write_end,
103 };
104
105 static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
106                                   unsigned long nr_segs, loff_t ppos)
107 {
108         ssize_t retval;
109         struct file *file = iocb->ki_filp;
110         struct inode *inode = file->f_path.dentry->d_inode;
111         int err, pos;
112         size_t count = iocb->ki_left;
113         struct udf_inode_info *iinfo = UDF_I(inode);
114
115         down_write(&iinfo->i_data_sem);
116         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
117                 if (file->f_flags & O_APPEND)
118                         pos = inode->i_size;
119                 else
120                         pos = ppos;
121
122                 if (inode->i_sb->s_blocksize <
123                                 (udf_file_entry_alloc_offset(inode) +
124                                                 pos + count)) {
125                         udf_expand_file_adinicb(inode, pos + count, &err);
126                         if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
127                                 udf_debug("udf_expand_adinicb: err=%d\n", err);
128                                 up_write(&iinfo->i_data_sem);
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         up_write(&iinfo->i_data_sem);
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 long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
148 {
149         struct inode *inode = filp->f_dentry->d_inode;
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", inode->i_ino);
155                 result = -EPERM;
156                 goto out;
157         }
158
159         if (!arg) {
160                 udf_debug("invalid argument to udf_ioctl\n");
161                 result = -EINVAL;
162                 goto out;
163         }
164
165         switch (cmd) {
166         case UDF_GETVOLIDENT:
167                 if (copy_to_user((char __user *)arg,
168                                  UDF_SB(inode->i_sb)->s_volume_ident, 32))
169                         result = -EFAULT;
170                 else
171                         result = 0;
172                 goto out;
173         case UDF_RELOCATE_BLOCKS:
174                 if (!capable(CAP_SYS_ADMIN)) {
175                         result = -EACCES;
176                         goto out;
177                 }
178                 if (get_user(old_block, (long __user *)arg)) {
179                         result = -EFAULT;
180                         goto out;
181                 }
182                 result = udf_relocate_blocks(inode->i_sb,
183                                                 old_block, &new_block);
184                 if (result == 0)
185                         result = put_user(new_block, (long __user *)arg);
186                 goto out;
187         case UDF_GETEASIZE:
188                 result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
189                 goto out;
190         case UDF_GETEABLOCK:
191                 result = copy_to_user((char __user *)arg,
192                                       UDF_I(inode)->i_ext.i_data,
193                                       UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
194                 goto out;
195         }
196
197 out:
198         return result;
199 }
200
201 static int udf_release_file(struct inode *inode, struct file *filp)
202 {
203         if (filp->f_mode & FMODE_WRITE) {
204                 mutex_lock(&inode->i_mutex);
205                 down_write(&UDF_I(inode)->i_data_sem);
206                 udf_discard_prealloc(inode);
207                 udf_truncate_tail_extent(inode);
208                 up_write(&UDF_I(inode)->i_data_sem);
209                 mutex_unlock(&inode->i_mutex);
210         }
211         return 0;
212 }
213
214 const struct file_operations udf_file_operations = {
215         .read                   = do_sync_read,
216         .aio_read               = generic_file_aio_read,
217         .unlocked_ioctl         = udf_ioctl,
218         .open                   = generic_file_open,
219         .mmap                   = generic_file_mmap,
220         .write                  = do_sync_write,
221         .aio_write              = udf_file_aio_write,
222         .release                = udf_release_file,
223         .fsync                  = generic_file_fsync,
224         .splice_read            = generic_file_splice_read,
225         .llseek                 = generic_file_llseek,
226 };
227
228 static int udf_setattr(struct dentry *dentry, struct iattr *attr)
229 {
230         struct inode *inode = dentry->d_inode;
231         int error;
232
233         error = inode_change_ok(inode, attr);
234         if (error)
235                 return error;
236
237         if ((attr->ia_valid & ATTR_SIZE) &&
238             attr->ia_size != i_size_read(inode)) {
239                 error = vmtruncate(inode, attr->ia_size);
240                 if (error)
241                         return error;
242         }
243
244         setattr_copy(inode, attr);
245         mark_inode_dirty(inode);
246         return 0;
247 }
248
249 const struct inode_operations udf_file_inode_operations = {
250         .setattr                = udf_setattr,
251         .truncate               = udf_truncate,
252 };