blob: 82440b731142f0b1ec8d2e2281ca30d0087b9f3f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * dir.c
3 *
4 * PURPOSE
5 * Directory handling routines for the OSTA-UDF(tm) filesystem.
6 *
7 * CONTACTS
8 * E-mail regarding any portion of the Linux UDF file system should be
9 * directed to the development team mailing list (run by majordomo):
10 * linux_udf@hpesjro.fc.hp.com
11 *
12 * COPYRIGHT
13 * This file is distributed under the terms of the GNU General Public
14 * License (GPL). Copies of the GPL can be obtained from:
15 * ftp://prep.ai.mit.edu/pub/gnu/GPL
16 * Each contributing author retains all rights to their own work.
17 *
18 * (C) 1998-2004 Ben Fennema
19 *
20 * HISTORY
21 *
22 * 10/05/98 dgb Split directory operations into its own file
23 * Implemented directory reads via do_udf_readdir
24 * 10/06/98 Made directory operations work!
25 * 11/17/98 Rewrote directory to support ICBTAG_FLAG_AD_LONG
26 * 11/25/98 blf Rewrote directory handling (readdir+lookup) to support reading
27 * across blocks.
28 * 12/12/98 Split out the lookup code to namei.c. bulk of directory
29 * code now in directory.c:udf_fileident_read.
30 */
31
32#include "udfdecl.h"
33
34#include <linux/string.h>
35#include <linux/errno.h>
36#include <linux/mm.h>
37#include <linux/slab.h>
38#include <linux/smp_lock.h>
39#include <linux/buffer_head.h>
40
41#include "udf_i.h"
42#include "udf_sb.h"
43
44/* Prototypes for file operations */
45static int udf_readdir(struct file *, void *, filldir_t);
46static int do_udf_readdir(struct inode *, struct file *, filldir_t, void *);
47
48/* readdir and lookup functions */
49
50struct file_operations udf_dir_operations = {
51 .read = generic_read_dir,
52 .readdir = udf_readdir,
53 .ioctl = udf_ioctl,
54 .fsync = udf_fsync_file,
55};
56
57/*
58 * udf_readdir
59 *
60 * PURPOSE
61 * Read a directory entry.
62 *
63 * DESCRIPTION
64 * Optional - sys_getdents() will return -ENOTDIR if this routine is not
65 * available.
66 *
67 * Refer to sys_getdents() in fs/readdir.c
68 * sys_getdents() -> .
69 *
70 * PRE-CONDITIONS
71 * filp Pointer to directory file.
72 * buf Pointer to directory entry buffer.
73 * filldir Pointer to filldir function.
74 *
75 * POST-CONDITIONS
76 * <return> >=0 on success.
77 *
78 * HISTORY
79 * July 1, 1997 - Andrew E. Mileski
80 * Written, tested, and released.
81 */
82
83int udf_readdir(struct file *filp, void *dirent, filldir_t filldir)
84{
85 struct inode *dir = filp->f_dentry->d_inode;
86 int result;
87
88 lock_kernel();
89
90 if ( filp->f_pos == 0 )
91 {
92 if (filldir(dirent, ".", 1, filp->f_pos, dir->i_ino, DT_DIR) < 0)
93 {
94 unlock_kernel();
95 return 0;
96 }
97 filp->f_pos ++;
98 }
99
100 result = do_udf_readdir(dir, filp, filldir, dirent);
101 unlock_kernel();
102 return result;
103}
104
105static int
106do_udf_readdir(struct inode * dir, struct file *filp, filldir_t filldir, void *dirent)
107{
108 struct udf_fileident_bh fibh;
109 struct fileIdentDesc *fi=NULL;
110 struct fileIdentDesc cfi;
111 int block, iblock;
112 loff_t nf_pos = filp->f_pos - 1;
113 int flen;
114 char fname[UDF_NAME_LEN];
115 char *nameptr;
116 uint16_t liu;
117 uint8_t lfi;
118 loff_t size = (udf_ext0_offset(dir) + dir->i_size) >> 2;
119 struct buffer_head * bh = NULL, * tmp, * bha[16];
120 kernel_lb_addr bloc, eloc;
121 uint32_t extoffset, elen, offset;
122 int i, num;
123 unsigned int dt_type;
124
125 if (nf_pos >= size)
126 return 0;
127
128 if (nf_pos == 0)
129 nf_pos = (udf_ext0_offset(dir) >> 2);
130
131 fibh.soffset = fibh.eoffset = (nf_pos & ((dir->i_sb->s_blocksize - 1) >> 2)) << 2;
132 if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_IN_ICB)
133 fibh.sbh = fibh.ebh = NULL;
134 else if (inode_bmap(dir, nf_pos >> (dir->i_sb->s_blocksize_bits - 2),
135 &bloc, &extoffset, &eloc, &elen, &offset, &bh) == (EXT_RECORDED_ALLOCATED >> 30))
136 {
137 offset >>= dir->i_sb->s_blocksize_bits;
138 block = udf_get_lb_pblock(dir->i_sb, eloc, offset);
139 if ((++offset << dir->i_sb->s_blocksize_bits) < elen)
140 {
141 if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_SHORT)
142 extoffset -= sizeof(short_ad);
143 else if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_LONG)
144 extoffset -= sizeof(long_ad);
145 }
146 else
147 offset = 0;
148
149 if (!(fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block)))
150 {
151 udf_release_data(bh);
152 return -EIO;
153 }
154
155 if (!(offset & ((16 >> (dir->i_sb->s_blocksize_bits - 9))-1)))
156 {
157 i = 16 >> (dir->i_sb->s_blocksize_bits - 9);
158 if (i+offset > (elen >> dir->i_sb->s_blocksize_bits))
159 i = (elen >> dir->i_sb->s_blocksize_bits)-offset;
160 for (num=0; i>0; i--)
161 {
162 block = udf_get_lb_pblock(dir->i_sb, eloc, offset+i);
163 tmp = udf_tgetblk(dir->i_sb, block);
164 if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
165 bha[num++] = tmp;
166 else
167 brelse(tmp);
168 }
169 if (num)
170 {
171 ll_rw_block(READA, num, bha);
172 for (i=0; i<num; i++)
173 brelse(bha[i]);
174 }
175 }
176 }
177 else
178 {
179 udf_release_data(bh);
180 return -ENOENT;
181 }
182
183 while ( nf_pos < size )
184 {
185 filp->f_pos = nf_pos + 1;
186
187 fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &bloc, &extoffset, &eloc, &elen, &offset, &bh);
188
189 if (!fi)
190 {
191 if (fibh.sbh != fibh.ebh)
192 udf_release_data(fibh.ebh);
193 udf_release_data(fibh.sbh);
194 udf_release_data(bh);
195 return 0;
196 }
197
198 liu = le16_to_cpu(cfi.lengthOfImpUse);
199 lfi = cfi.lengthFileIdent;
200
201 if (fibh.sbh == fibh.ebh)
202 nameptr = fi->fileIdent + liu;
203 else
204 {
205 int poffset; /* Unpaded ending offset */
206
207 poffset = fibh.soffset + sizeof(struct fileIdentDesc) + liu + lfi;
208
209 if (poffset >= lfi)
210 nameptr = (char *)(fibh.ebh->b_data + poffset - lfi);
211 else
212 {
213 nameptr = fname;
214 memcpy(nameptr, fi->fileIdent + liu, lfi - poffset);
215 memcpy(nameptr + lfi - poffset, fibh.ebh->b_data, poffset);
216 }
217 }
218
219 if ( (cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) != 0 )
220 {
221 if ( !UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNDELETE) )
222 continue;
223 }
224
225 if ( (cfi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0 )
226 {
227 if ( !UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNHIDE) )
228 continue;
229 }
230
231 if ( cfi.fileCharacteristics & FID_FILE_CHAR_PARENT )
232 {
233 iblock = parent_ino(filp->f_dentry);
234 flen = 2;
235 memcpy(fname, "..", flen);
236 dt_type = DT_DIR;
237 }
238 else
239 {
240 kernel_lb_addr tloc = lelb_to_cpu(cfi.icb.extLocation);
241
242 iblock = udf_get_lb_pblock(dir->i_sb, tloc, 0);
243 flen = udf_get_filename(dir->i_sb, nameptr, fname, lfi);
244 dt_type = DT_UNKNOWN;
245 }
246
247 if (flen)
248 {
249 if (filldir(dirent, fname, flen, filp->f_pos, iblock, dt_type) < 0)
250 {
251 if (fibh.sbh != fibh.ebh)
252 udf_release_data(fibh.ebh);
253 udf_release_data(fibh.sbh);
254 udf_release_data(bh);
255 return 0;
256 }
257 }
258 } /* end while */
259
260 filp->f_pos = nf_pos + 1;
261
262 if (fibh.sbh != fibh.ebh)
263 udf_release_data(fibh.ebh);
264 udf_release_data(fibh.sbh);
265 udf_release_data(bh);
266
267 return 0;
268}