xref: /nrf52832-nimble/rt-thread/components/dfs/filesystems/jffs2/src/dir-ecos.c (revision 104654410c56c573564690304ae786df310c91fc)
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright (C) 2001-2003 Free Software Foundation, Inc.
5  *
6  * Created by David Woodhouse <[email protected]>
7  *
8  * For licensing information, see the file 'LICENCE' in this directory.
9  *
10  * $Id: dir-ecos.c,v 1.11 2005/02/08 19:36:27 lunn Exp $
11  *
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/crc32.h>
16 #include "nodelist.h"
17 
18 /***********************************************************************/
19 
20 /* Takes length argument because it can be either NUL-terminated or '/'-terminated */
jffs2_lookup(struct _inode * dir_i,const unsigned char * d_name,int namelen)21 struct _inode *jffs2_lookup(struct _inode *dir_i, const unsigned char *d_name, int namelen)
22 {
23 	struct jffs2_inode_info *dir_f;
24 	struct jffs2_full_dirent *fd = NULL, *fd_list;
25 	uint32_t ino = 0;
26 	uint32_t hash = full_name_hash(d_name, namelen);
27 	struct _inode *inode = NULL;
28 
29 	D1(printk("jffs2_lookup()\n"));
30 
31 	dir_f = JFFS2_INODE_INFO(dir_i);
32 
33 	down(&dir_f->sem);
34 
35 	/* NB: The 2.2 backport will need to explicitly check for '.' and '..' here */
36 	for (fd_list = dir_f->dents; fd_list && fd_list->nhash <= hash; fd_list = fd_list->next) {
37 		if (fd_list->nhash == hash &&
38 		    (!fd || fd_list->version > fd->version) &&
39 		    strlen((char *)fd_list->name) == namelen &&
40 		    !strncmp((char *)fd_list->name, (char *)d_name, namelen)) {
41 			fd = fd_list;
42 		}
43 	}
44 	if (fd)
45 		ino = fd->ino;
46 	up(&dir_f->sem);
47 	if (ino) {
48 		inode = jffs2_iget(dir_i->i_sb, ino);
49 		if (IS_ERR(inode)) {
50 			printk("jffs2_iget() failed for ino #%u\n", ino);
51 			return inode;
52 		}
53 	}
54 
55 	return inode;
56 }
57 
58 /***********************************************************************/
59 
60 
61 
jffs2_create(struct _inode * dir_i,const unsigned char * d_name,int mode,struct _inode ** new_i)62 int jffs2_create(struct _inode *dir_i, const unsigned char *d_name, int mode,
63                  struct _inode **new_i)
64 {
65 	struct jffs2_raw_inode *ri;
66 	struct jffs2_inode_info *f, *dir_f;
67 	struct jffs2_sb_info *c;
68 	struct _inode *inode;
69 	int ret;
70 
71 	ri = jffs2_alloc_raw_inode();
72 	if (!ri)
73 		return -ENOMEM;
74 
75 	c = JFFS2_SB_INFO(dir_i->i_sb);
76 
77 	D1(printk(KERN_DEBUG "jffs2_create()\n"));
78 
79 	inode = jffs2_new_inode(dir_i, mode, ri);
80 
81 	if (IS_ERR(inode)) {
82 		D1(printk(KERN_DEBUG "jffs2_new_inode() failed\n"));
83 		jffs2_free_raw_inode(ri);
84 		return PTR_ERR(inode);
85 	}
86 
87 	f = JFFS2_INODE_INFO(inode);
88 	dir_f = JFFS2_INODE_INFO(dir_i);
89 
90 	ret = jffs2_do_create(c, dir_f, f, ri,
91 			      (const char *)d_name,
92                               strlen((char *)d_name));
93 
94 	if (ret) {
95 		inode->i_nlink = 0;
96 		jffs2_iput(inode);
97 		jffs2_free_raw_inode(ri);
98 		return ret;
99 	}
100 
101 	jffs2_free_raw_inode(ri);
102 
103 	D1(printk(KERN_DEBUG "jffs2_create: Created ino #%lu with mode %o, nlink %d(%d)\n",
104 		  inode->i_ino, inode->i_mode, inode->i_nlink, f->inocache->nlink));
105         *new_i = inode;
106 	return 0;
107 }
108 
109 /***********************************************************************/
110 
111 
jffs2_unlink(struct _inode * dir_i,struct _inode * d_inode,const unsigned char * d_name)112 int jffs2_unlink(struct _inode *dir_i, struct _inode *d_inode, const unsigned char *d_name)
113 {
114 	struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
115 	struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
116 	struct jffs2_inode_info *dead_f = JFFS2_INODE_INFO(d_inode);
117 	int ret;
118 
119 	ret = jffs2_do_unlink(c, dir_f, (const char *)d_name,
120 			       strlen((char *)d_name), dead_f);
121 	if (dead_f->inocache)
122 		d_inode->i_nlink = dead_f->inocache->nlink;
123 	return ret;
124 }
125 /***********************************************************************/
126 
127 
jffs2_link(struct _inode * old_d_inode,struct _inode * dir_i,const unsigned char * d_name)128 int jffs2_link (struct _inode *old_d_inode, struct _inode *dir_i, const unsigned char *d_name)
129 {
130 	struct jffs2_sb_info *c = JFFS2_SB_INFO(old_d_inode->i_sb);
131 	struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_d_inode);
132 	struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
133 	int ret;
134 
135 	/* XXX: This is ugly */
136 	uint8_t type = (old_d_inode->i_mode & S_IFMT) >> 12;
137 	if (!type) type = DT_REG;
138 
139 	ret = jffs2_do_link(c, dir_f, f->inocache->ino, type,
140                             (const char * )d_name,
141                             strlen((char *)d_name));
142 
143 	if (!ret) {
144 		down(&f->sem);
145 		old_d_inode->i_nlink = ++f->inocache->nlink;
146 		up(&f->sem);
147 	}
148 	return ret;
149 }
150 
jffs2_mkdir(struct _inode * dir_i,const unsigned char * d_name,int mode)151 int jffs2_mkdir (struct _inode *dir_i, const unsigned char *d_name, int mode)
152 {
153 	struct jffs2_inode_info *f, *dir_f;
154 	struct jffs2_sb_info *c;
155 	struct _inode *inode;
156 	struct jffs2_raw_inode *ri;
157 	struct jffs2_raw_dirent *rd;
158 	struct jffs2_full_dnode *fn;
159 	struct jffs2_full_dirent *fd;
160 	int namelen;
161 	uint32_t alloclen, phys_ofs;
162 	int ret;
163 
164 	mode |= S_IFDIR;
165 
166 	ri = jffs2_alloc_raw_inode();
167 	if (!ri)
168 		return -ENOMEM;
169 
170 	c = JFFS2_SB_INFO(dir_i->i_sb);
171 
172 	/* Try to reserve enough space for both node and dirent.
173 	 * Just the node will do for now, though
174 	 */
175 	namelen = strlen((char *)d_name);
176 	ret = jffs2_reserve_space(c, sizeof(*ri), &phys_ofs, &alloclen, ALLOC_NORMAL);
177 
178 	if (ret) {
179 		jffs2_free_raw_inode(ri);
180 		return ret;
181 	}
182 
183 	inode = jffs2_new_inode(dir_i, mode, ri);
184 
185 	if (IS_ERR(inode)) {
186 		jffs2_free_raw_inode(ri);
187 		jffs2_complete_reservation(c);
188 		return PTR_ERR(inode);
189 	}
190 
191 	f = JFFS2_INODE_INFO(inode);
192 
193 	ri->data_crc = cpu_to_je32(0);
194 	ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
195 
196 	fn = jffs2_write_dnode(c, f, ri, NULL, 0, phys_ofs, ALLOC_NORMAL);
197 
198 	jffs2_free_raw_inode(ri);
199 
200 	if (IS_ERR(fn)) {
201 		/* Eeek. Wave bye bye */
202 		up(&f->sem);
203 		jffs2_complete_reservation(c);
204 		inode->i_nlink = 0;
205 		jffs2_iput(inode);
206 		return PTR_ERR(fn);
207 	}
208 	/* No data here. Only a metadata node, which will be
209 	   obsoleted by the first data write
210 	*/
211 	f->metadata = fn;
212 	up(&f->sem);
213 
214 	jffs2_complete_reservation(c);
215 	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen, ALLOC_NORMAL);
216 	if (ret) {
217 		/* Eep. */
218 		inode->i_nlink = 0;
219 		jffs2_iput(inode);
220 		return ret;
221 	}
222 
223 	rd = jffs2_alloc_raw_dirent();
224 	if (!rd) {
225 		/* Argh. Now we treat it like a normal delete */
226 		jffs2_complete_reservation(c);
227 		inode->i_nlink = 0;
228 		jffs2_iput(inode);
229 		return -ENOMEM;
230 	}
231 
232 	dir_f = JFFS2_INODE_INFO(dir_i);
233 	down(&dir_f->sem);
234 
235 	rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
236 	rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
237 	rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
238 	rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
239 
240 	rd->pino = cpu_to_je32(dir_i->i_ino);
241 	rd->version = cpu_to_je32(++dir_f->highest_version);
242 	rd->ino = cpu_to_je32(inode->i_ino);
243 	rd->mctime = cpu_to_je32(jffs2_get_timestamp());
244 	rd->nsize = namelen;
245 	rd->type = DT_DIR;
246 	rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
247 	rd->name_crc = cpu_to_je32(crc32(0, d_name, namelen));
248 
249 	fd = jffs2_write_dirent(c, dir_f, rd, d_name, namelen, phys_ofs, ALLOC_NORMAL);
250 
251 	jffs2_complete_reservation(c);
252 	jffs2_free_raw_dirent(rd);
253 
254 	if (IS_ERR(fd)) {
255 		/* dirent failed to write. Delete the inode normally
256 		   as if it were the final unlink() */
257 		up(&dir_f->sem);
258 		inode->i_nlink = 0;
259 		jffs2_iput(inode);
260 		return PTR_ERR(fd);
261 	}
262 
263 	/* Link the fd into the inode's list, obsoleting an old
264 	   one if necessary. */
265 	jffs2_add_fd_to_list(c, fd, &dir_f->dents);
266 	up(&dir_f->sem);
267 
268 	jffs2_iput(inode);
269 	return 0;
270 }
271 
jffs2_rmdir(struct _inode * dir_i,struct _inode * d_inode,const unsigned char * d_name)272 int jffs2_rmdir (struct _inode *dir_i, struct _inode *d_inode, const unsigned char *d_name)
273 {
274 	struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode);
275 	struct jffs2_full_dirent *fd;
276 
277 	for (fd = f->dents ; fd; fd = fd->next) {
278 		if (fd->ino)
279 			return EPERM; //-ENOTEMPTY;
280 	}
281 	return jffs2_unlink(dir_i, d_inode, d_name);
282 }
283 
jffs2_rename(struct _inode * old_dir_i,struct _inode * d_inode,const unsigned char * old_d_name,struct _inode * new_dir_i,const unsigned char * new_d_name)284 int jffs2_rename (struct _inode *old_dir_i, struct _inode *d_inode, const unsigned char *old_d_name,
285 		  struct _inode *new_dir_i, const unsigned char *new_d_name)
286 {
287 	int ret;
288 	struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb);
289 	struct jffs2_inode_info *victim_f = NULL;
290 	uint8_t type;
291 
292 #if 0 /* FIXME -- this really doesn't belong in individual file systems.
293 	 The fileio code ought to do this for us, or at least part of it */
294 	if (new_dentry->d_inode) {
295 		if (S_ISDIR(d_inode->i_mode) &&
296 		    !S_ISDIR(new_dentry->d_inode->i_mode)) {
297 			/* Cannot rename directory over non-directory */
298 			return -EINVAL;
299 		}
300 
301 		victim_f = JFFS2_INODE_INFO(new_dentry->d_inode);
302 
303 		if (S_ISDIR(new_dentry->d_inode->i_mode)) {
304 			struct jffs2_full_dirent *fd;
305 
306 			if (!S_ISDIR(d_inode->i_mode)) {
307 				/* Cannot rename non-directory over directory */
308 				return -EINVAL;
309 			}
310 			down(&victim_f->sem);
311 			for (fd = victim_f->dents; fd; fd = fd->next) {
312 				if (fd->ino) {
313 					up(&victim_f->sem);
314 					return -ENOTEMPTY;
315 				}
316 			}
317 			up(&victim_f->sem);
318 		}
319 	}
320 #endif
321 
322 	/* XXX: We probably ought to alloc enough space for
323 	   both nodes at the same time. Writing the new link,
324 	   then getting -ENOSPC, is quite bad :)
325 	*/
326 
327 	/* Make a hard link */
328 
329 	/* XXX: This is ugly */
330 	type = (d_inode->i_mode & S_IFMT) >> 12;
331 	if (!type) type = DT_REG;
332 
333 	ret = jffs2_do_link(c, JFFS2_INODE_INFO(new_dir_i),
334 			    d_inode->i_ino, type,
335 			    (const char *)new_d_name,
336                             strlen((char *)new_d_name));
337 
338 	if (ret)
339 		return ret;
340 
341 	if (victim_f) {
342 		/* There was a victim. Kill it off nicely */
343 		/* Don't oops if the victim was a dirent pointing to an
344 		   inode which didn't exist. */
345 		if (victim_f->inocache) {
346 			down(&victim_f->sem);
347 			victim_f->inocache->nlink--;
348 			up(&victim_f->sem);
349 		}
350 	}
351 
352 	/* Unlink the original */
353 	ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
354                               (const char *)old_d_name,
355                               strlen((char *)old_d_name), NULL);
356 
357 	if (ret) {
358 		/* Oh shit. We really ought to make a single node which can do both atomically */
359 		struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode);
360 		down(&f->sem);
361 		if (f->inocache)
362 			d_inode->i_nlink = f->inocache->nlink++;
363 		up(&f->sem);
364 
365 		printk(KERN_NOTICE "jffs2_rename(): Link succeeded, unlink failed (err %d). You now have a hard link\n", ret);
366 	}
367 	return ret;
368 }
369 
370