ia64/linux-2.6.18-xen.hg

view fs/udf/dir.c @ 524:7f8b544237bf

netfront: Allow netfront in domain 0.

This is useful if your physical network device is in a utility domain.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:18:58 2008 +0100 (2008-04-15)
parents 831230e53067
children
line source
1 /*
2 * dir.c
3 *
4 * PURPOSE
5 * Directory 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) 1998-2004 Ben Fennema
14 *
15 * HISTORY
16 *
17 * 10/05/98 dgb Split directory operations into its own file
18 * Implemented directory reads via do_udf_readdir
19 * 10/06/98 Made directory operations work!
20 * 11/17/98 Rewrote directory to support ICBTAG_FLAG_AD_LONG
21 * 11/25/98 blf Rewrote directory handling (readdir+lookup) to support reading
22 * across blocks.
23 * 12/12/98 Split out the lookup code to namei.c. bulk of directory
24 * code now in directory.c:udf_fileident_read.
25 */
27 #include "udfdecl.h"
29 #include <linux/string.h>
30 #include <linux/errno.h>
31 #include <linux/mm.h>
32 #include <linux/slab.h>
33 #include <linux/smp_lock.h>
34 #include <linux/buffer_head.h>
36 #include "udf_i.h"
37 #include "udf_sb.h"
39 /* Prototypes for file operations */
40 static int udf_readdir(struct file *, void *, filldir_t);
41 static int do_udf_readdir(struct inode *, struct file *, filldir_t, void *);
43 /* readdir and lookup functions */
45 const struct file_operations udf_dir_operations = {
46 .read = generic_read_dir,
47 .readdir = udf_readdir,
48 .ioctl = udf_ioctl,
49 .fsync = udf_fsync_file,
50 };
52 /*
53 * udf_readdir
54 *
55 * PURPOSE
56 * Read a directory entry.
57 *
58 * DESCRIPTION
59 * Optional - sys_getdents() will return -ENOTDIR if this routine is not
60 * available.
61 *
62 * Refer to sys_getdents() in fs/readdir.c
63 * sys_getdents() -> .
64 *
65 * PRE-CONDITIONS
66 * filp Pointer to directory file.
67 * buf Pointer to directory entry buffer.
68 * filldir Pointer to filldir function.
69 *
70 * POST-CONDITIONS
71 * <return> >=0 on success.
72 *
73 * HISTORY
74 * July 1, 1997 - Andrew E. Mileski
75 * Written, tested, and released.
76 */
78 int udf_readdir(struct file *filp, void *dirent, filldir_t filldir)
79 {
80 struct inode *dir = filp->f_dentry->d_inode;
81 int result;
83 lock_kernel();
85 if ( filp->f_pos == 0 )
86 {
87 if (filldir(dirent, ".", 1, filp->f_pos, dir->i_ino, DT_DIR) < 0)
88 {
89 unlock_kernel();
90 return 0;
91 }
92 filp->f_pos ++;
93 }
95 result = do_udf_readdir(dir, filp, filldir, dirent);
96 unlock_kernel();
97 return result;
98 }
100 static int
101 do_udf_readdir(struct inode * dir, struct file *filp, filldir_t filldir, void *dirent)
102 {
103 struct udf_fileident_bh fibh;
104 struct fileIdentDesc *fi=NULL;
105 struct fileIdentDesc cfi;
106 int block, iblock;
107 loff_t nf_pos = filp->f_pos - 1;
108 int flen;
109 char fname[UDF_NAME_LEN];
110 char *nameptr;
111 uint16_t liu;
112 uint8_t lfi;
113 loff_t size = (udf_ext0_offset(dir) + dir->i_size) >> 2;
114 struct buffer_head * bh = NULL, * tmp, * bha[16];
115 kernel_lb_addr bloc, eloc;
116 uint32_t extoffset, elen, offset;
117 int i, num;
118 unsigned int dt_type;
120 if (nf_pos >= size)
121 return 0;
123 if (nf_pos == 0)
124 nf_pos = (udf_ext0_offset(dir) >> 2);
126 fibh.soffset = fibh.eoffset = (nf_pos & ((dir->i_sb->s_blocksize - 1) >> 2)) << 2;
127 if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_IN_ICB)
128 fibh.sbh = fibh.ebh = NULL;
129 else if (inode_bmap(dir, nf_pos >> (dir->i_sb->s_blocksize_bits - 2),
130 &bloc, &extoffset, &eloc, &elen, &offset, &bh) == (EXT_RECORDED_ALLOCATED >> 30))
131 {
132 offset >>= dir->i_sb->s_blocksize_bits;
133 block = udf_get_lb_pblock(dir->i_sb, eloc, offset);
134 if ((++offset << dir->i_sb->s_blocksize_bits) < elen)
135 {
136 if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_SHORT)
137 extoffset -= sizeof(short_ad);
138 else if (UDF_I_ALLOCTYPE(dir) == ICBTAG_FLAG_AD_LONG)
139 extoffset -= sizeof(long_ad);
140 }
141 else
142 offset = 0;
144 if (!(fibh.sbh = fibh.ebh = udf_tread(dir->i_sb, block)))
145 {
146 udf_release_data(bh);
147 return -EIO;
148 }
150 if (!(offset & ((16 >> (dir->i_sb->s_blocksize_bits - 9))-1)))
151 {
152 i = 16 >> (dir->i_sb->s_blocksize_bits - 9);
153 if (i+offset > (elen >> dir->i_sb->s_blocksize_bits))
154 i = (elen >> dir->i_sb->s_blocksize_bits)-offset;
155 for (num=0; i>0; i--)
156 {
157 block = udf_get_lb_pblock(dir->i_sb, eloc, offset+i);
158 tmp = udf_tgetblk(dir->i_sb, block);
159 if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
160 bha[num++] = tmp;
161 else
162 brelse(tmp);
163 }
164 if (num)
165 {
166 ll_rw_block(READA, num, bha);
167 for (i=0; i<num; i++)
168 brelse(bha[i]);
169 }
170 }
171 }
172 else
173 {
174 udf_release_data(bh);
175 return -ENOENT;
176 }
178 while ( nf_pos < size )
179 {
180 filp->f_pos = nf_pos + 1;
182 fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &bloc, &extoffset, &eloc, &elen, &offset, &bh);
184 if (!fi)
185 {
186 if (fibh.sbh != fibh.ebh)
187 udf_release_data(fibh.ebh);
188 udf_release_data(fibh.sbh);
189 udf_release_data(bh);
190 return 0;
191 }
193 liu = le16_to_cpu(cfi.lengthOfImpUse);
194 lfi = cfi.lengthFileIdent;
196 if (fibh.sbh == fibh.ebh)
197 nameptr = fi->fileIdent + liu;
198 else
199 {
200 int poffset; /* Unpaded ending offset */
202 poffset = fibh.soffset + sizeof(struct fileIdentDesc) + liu + lfi;
204 if (poffset >= lfi)
205 nameptr = (char *)(fibh.ebh->b_data + poffset - lfi);
206 else
207 {
208 nameptr = fname;
209 memcpy(nameptr, fi->fileIdent + liu, lfi - poffset);
210 memcpy(nameptr + lfi - poffset, fibh.ebh->b_data, poffset);
211 }
212 }
214 if ( (cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) != 0 )
215 {
216 if ( !UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNDELETE) )
217 continue;
218 }
220 if ( (cfi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0 )
221 {
222 if ( !UDF_QUERY_FLAG(dir->i_sb, UDF_FLAG_UNHIDE) )
223 continue;
224 }
226 if ( cfi.fileCharacteristics & FID_FILE_CHAR_PARENT )
227 {
228 iblock = parent_ino(filp->f_dentry);
229 flen = 2;
230 memcpy(fname, "..", flen);
231 dt_type = DT_DIR;
232 }
233 else
234 {
235 kernel_lb_addr tloc = lelb_to_cpu(cfi.icb.extLocation);
237 iblock = udf_get_lb_pblock(dir->i_sb, tloc, 0);
238 flen = udf_get_filename(dir->i_sb, nameptr, fname, lfi);
239 dt_type = DT_UNKNOWN;
240 }
242 if (flen)
243 {
244 if (filldir(dirent, fname, flen, filp->f_pos, iblock, dt_type) < 0)
245 {
246 if (fibh.sbh != fibh.ebh)
247 udf_release_data(fibh.ebh);
248 udf_release_data(fibh.sbh);
249 udf_release_data(bh);
250 return 0;
251 }
252 }
253 } /* end while */
255 filp->f_pos = nf_pos + 1;
257 if (fibh.sbh != fibh.ebh)
258 udf_release_data(fibh.ebh);
259 udf_release_data(fibh.sbh);
260 udf_release_data(bh);
262 return 0;
263 }