1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright (C) 2001 Red Hat, Inc.
5  *
6  * Created by David Woodhouse <dwmw2@cambridge.redhat.com>
7  *
8  * The original JFFS, from which the design for JFFS2 was derived,
9  * was designed and implemented by Axis Communications AB.
10  *
11  * The contents of this file are subject to the Red Hat eCos Public
12  * License Version 1.1 (the "Licence"); you may not use this file
13  * except in compliance with the Licence.  You may obtain a copy of
14  * the Licence at http://www.redhat.com/
15  *
16  * Software distributed under the Licence is distributed on an "AS IS"
17  * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.
18  * See the Licence for the specific language governing rights and
19  * limitations under the Licence.
20  *
21  * The Original Code is JFFS2 - Journalling Flash File System, version 2
22  *
23  * Alternatively, the contents of this file may be used under the
24  * terms of the GNU General Public License version 2 (the "GPL"), in
25  * which case the provisions of the GPL are applicable instead of the
26  * above.  If you wish to allow the use of your version of this file
27  * only under the terms of the GPL and not to allow others to use your
28  * version of this file under the RHEPL, indicate your decision by
29  * deleting the provisions above and replace them with the notice and
30  * other provisions required by the GPL.  If you do not delete the
31  * provisions above, a recipient may use your version of this file
32  * under either the RHEPL or the GPL.
33  *
34  * $Id: erase.c,v 1.24.2.1 2003/11/02 13:51:17 dwmw2 Exp $
35  *
36  */
37 #include <linux/kernel.h>
38 #include <linux/slab.h>
39 #include <linux/mtd/mtd.h>
40 #include <linux/jffs2.h>
41 #include <linux/interrupt.h>
42 #include "nodelist.h"
43 #include <linux/crc32.h>
44 
45 struct erase_priv_struct {
46 	struct jffs2_eraseblock *jeb;
47 	struct jffs2_sb_info *c;
48 };
49 
50 static void jffs2_erase_callback(struct erase_info *);
51 static void jffs2_free_all_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
52 
jffs2_erase_block(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)53 void jffs2_erase_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
54 {
55 	struct erase_info *instr;
56 	int ret;
57 
58 	instr = kmalloc(sizeof(struct erase_info) + sizeof(struct erase_priv_struct), GFP_KERNEL);
59 	if (!instr) {
60 		printk(KERN_WARNING "kmalloc for struct erase_info in jffs2_erase_block failed. Refiling block for later\n");
61 		spin_lock_bh(&c->erase_completion_lock);
62 		list_del(&jeb->list);
63 		list_add(&jeb->list, &c->erase_pending_list);
64 		c->erasing_size -= c->sector_size;
65 		spin_unlock_bh(&c->erase_completion_lock);
66 		return;
67 	}
68 
69 	memset(instr, 0, sizeof(*instr));
70 
71 	instr->mtd = c->mtd;
72 	instr->addr = jeb->offset;
73 	instr->len = c->sector_size;
74 	instr->callback = jffs2_erase_callback;
75 	instr->priv = (unsigned long)(&instr[1]);
76 
77 	((struct erase_priv_struct *)instr->priv)->jeb = jeb;
78 	((struct erase_priv_struct *)instr->priv)->c = c;
79 
80 	ret = c->mtd->erase(c->mtd, instr);
81 	if (!ret) {
82 		return;
83 	}
84 	if (ret == -ENOMEM || ret == -EAGAIN) {
85 		/* Erase failed immediately. Refile it on the list */
86 		D1(printk(KERN_DEBUG "Erase at 0x%08x failed: %d. Refiling on erase_pending_list\n", jeb->offset, ret));
87 		spin_lock_bh(&c->erase_completion_lock);
88 		list_del(&jeb->list);
89 		list_add(&jeb->list, &c->erase_pending_list);
90 		c->erasing_size -= c->sector_size;
91 		spin_unlock_bh(&c->erase_completion_lock);
92 		kfree(instr);
93 		return;
94 	}
95 
96 	if (ret == -EROFS)
97 		printk(KERN_WARNING "Erase at 0x%08x failed immediately: -EROFS. Is the sector locked?\n", jeb->offset);
98 	else
99 		printk(KERN_WARNING "Erase at 0x%08x failed immediately: errno %d\n", jeb->offset, ret);
100 	spin_lock_bh(&c->erase_completion_lock);
101 	list_del(&jeb->list);
102 	list_add(&jeb->list, &c->bad_list);
103 	c->nr_erasing_blocks--;
104 	c->bad_size += c->sector_size;
105 	c->erasing_size -= c->sector_size;
106 	spin_unlock_bh(&c->erase_completion_lock);
107 	wake_up(&c->erase_wait);
108 	kfree(instr);
109 }
110 
jffs2_erase_pending_blocks(struct jffs2_sb_info * c)111 void jffs2_erase_pending_blocks(struct jffs2_sb_info *c)
112 {
113 	struct jffs2_eraseblock *jeb;
114 
115 	spin_lock_bh(&c->erase_completion_lock);
116 	while (!list_empty(&c->erase_pending_list)) {
117 
118 		jeb = list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list);
119 
120 		D1(printk(KERN_DEBUG "Starting erase of pending block 0x%08x\n", jeb->offset));
121 
122 		list_del(&jeb->list);
123 		c->erasing_size += c->sector_size;
124 		c->free_size -= jeb->free_size;
125 		c->used_size -= jeb->used_size;
126 		c->dirty_size -= jeb->dirty_size;
127 		jeb->used_size = jeb->dirty_size = jeb->free_size = 0;
128 		jffs2_free_all_node_refs(c, jeb);
129 		list_add(&jeb->list, &c->erasing_list);
130 		spin_unlock_bh(&c->erase_completion_lock);
131 
132 		jffs2_erase_block(c, jeb);
133 		/* Be nice */
134 		if (current->need_resched)
135 			schedule();
136 		spin_lock_bh(&c->erase_completion_lock);
137 	}
138 	spin_unlock_bh(&c->erase_completion_lock);
139 	D1(printk(KERN_DEBUG "jffs2_erase_pending_blocks completed\n"));
140 }
141 
142 
jffs2_erase_callback(struct erase_info * instr)143 static void jffs2_erase_callback(struct erase_info *instr)
144 {
145 	struct erase_priv_struct *priv = (void *)instr->priv;
146 
147 	if(instr->state != MTD_ERASE_DONE) {
148 		printk(KERN_WARNING "Erase at 0x%08x finished, but state != MTD_ERASE_DONE. State is 0x%x instead.\n", instr->addr, instr->state);
149 		spin_lock(&priv->c->erase_completion_lock);
150 		priv->c->erasing_size -= priv->c->sector_size;
151 		priv->c->bad_size += priv->c->sector_size;
152 		list_del(&priv->jeb->list);
153 		list_add(&priv->jeb->list, &priv->c->bad_list);
154 		priv->c->nr_erasing_blocks--;
155 		spin_unlock(&priv->c->erase_completion_lock);
156 		wake_up(&priv->c->erase_wait);
157 	} else {
158 		D1(printk(KERN_DEBUG "Erase completed successfully at 0x%08x\n", instr->addr));
159 		spin_lock(&priv->c->erase_completion_lock);
160 		list_del(&priv->jeb->list);
161 		list_add_tail(&priv->jeb->list, &priv->c->erase_complete_list);
162 		spin_unlock(&priv->c->erase_completion_lock);
163 	}
164 	/* Make sure someone picks up the block off the erase_complete list */
165 	OFNI_BS_2SFFJ(priv->c)->s_dirt = 1;
166 	kfree(instr);
167 }
168 
169 /* Hmmm. Maybe we should accept the extra space it takes and make
170    this a standard doubly-linked list? */
jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info * c,struct jffs2_raw_node_ref * ref,struct jffs2_eraseblock * jeb)171 static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c,
172 			struct jffs2_raw_node_ref *ref, struct jffs2_eraseblock *jeb)
173 {
174 	struct jffs2_inode_cache *ic = NULL;
175 	struct jffs2_raw_node_ref **prev;
176 
177 	prev = &ref->next_in_ino;
178 
179 	/* Walk the inode's list once, removing any nodes from this eraseblock */
180 	while (1) {
181 		if (!(*prev)->next_in_ino) {
182 			/* We're looking at the jffs2_inode_cache, which is
183 			   at the end of the linked list. Stash it and continue
184 			   from the beginning of the list */
185 			ic = (struct jffs2_inode_cache *)(*prev);
186 			prev = &ic->nodes;
187 			continue;
188 		}
189 
190 		if (((*prev)->flash_offset & ~(c->sector_size -1)) == jeb->offset) {
191 			/* It's in the block we're erasing */
192 			struct jffs2_raw_node_ref *this;
193 
194 			this = *prev;
195 			*prev = this->next_in_ino;
196 			this->next_in_ino = NULL;
197 
198 			if (this == ref)
199 				break;
200 
201 			continue;
202 		}
203 		/* Not to be deleted. Skip */
204 		prev = &((*prev)->next_in_ino);
205 	}
206 
207 	/* PARANOIA */
208 	if (!ic) {
209 		printk(KERN_WARNING "inode_cache not found in remove_node_refs()!!\n");
210 		return;
211 	}
212 
213 	D1(printk(KERN_DEBUG "Removed nodes in range 0x%08x-0x%08x from ino #%u\n",
214 		  jeb->offset, jeb->offset + c->sector_size, ic->ino));
215 
216 	D2({
217 		int i=0;
218 		struct jffs2_raw_node_ref *this;
219 		printk(KERN_DEBUG "After remove_node_refs_from_ino_list: \n" KERN_DEBUG);
220 
221 		this = ic->nodes;
222 
223 		while(this) {
224 			printk( "0x%08x(%d)->", this->flash_offset & ~3, this->flash_offset &3);
225 			if (++i == 5) {
226 				printk("\n" KERN_DEBUG);
227 				i=0;
228 			}
229 			this = this->next_in_ino;
230 		}
231 		printk("\n");
232 	});
233 
234 	if (ic->nodes == (void *)ic) {
235 		D1(printk(KERN_DEBUG "inocache for ino #%u is all gone now. Freeing\n", ic->ino));
236 		jffs2_del_ino_cache(c, ic);
237 		jffs2_free_inode_cache(ic);
238 	}
239 }
240 
jffs2_free_all_node_refs(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)241 static void jffs2_free_all_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
242 {
243 	struct jffs2_raw_node_ref *ref;
244 	D1(printk(KERN_DEBUG "Freeing all node refs for eraseblock offset 0x%08x\n", jeb->offset));
245 	while(jeb->first_node) {
246 		ref = jeb->first_node;
247 		jeb->first_node = ref->next_phys;
248 
249 		/* Remove from the inode-list */
250 		if (ref->next_in_ino)
251 			jffs2_remove_node_refs_from_ino_list(c, ref, jeb);
252 		/* else it was a non-inode node or already removed, so don't bother */
253 
254 		jffs2_free_raw_node_ref(ref);
255 	}
256 	jeb->last_node = NULL;
257 }
258 
jffs2_erase_pending_trigger(struct jffs2_sb_info * c)259 void jffs2_erase_pending_trigger(struct jffs2_sb_info *c)
260 {
261 	OFNI_BS_2SFFJ(c)->s_dirt = 1;
262 }
263 
jffs2_mark_erased_blocks(struct jffs2_sb_info * c)264 void jffs2_mark_erased_blocks(struct jffs2_sb_info *c)
265 {
266 	static struct jffs2_unknown_node marker = {JFFS2_MAGIC_BITMASK, JFFS2_NODETYPE_CLEANMARKER, sizeof(struct jffs2_unknown_node)};
267 	struct jffs2_eraseblock *jeb;
268 	struct jffs2_raw_node_ref *marker_ref;
269 	unsigned char *ebuf;
270 	ssize_t retlen;
271 	int ret;
272 
273 	marker.hdr_crc = crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4);
274 
275 	spin_lock_bh(&c->erase_completion_lock);
276 	while (!list_empty(&c->erase_complete_list)) {
277 		jeb = list_entry(c->erase_complete_list.next, struct jffs2_eraseblock, list);
278 		list_del(&jeb->list);
279 		spin_unlock_bh(&c->erase_completion_lock);
280 
281 		marker_ref = jffs2_alloc_raw_node_ref();
282 		if (!marker_ref) {
283 			printk(KERN_WARNING "Failed to allocate raw node ref for clean marker\n");
284 			/* Come back later */
285 			jffs2_erase_pending_trigger(c);
286 			return;
287 		}
288 
289 		ebuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
290 		if (!ebuf) {
291 			printk(KERN_WARNING "Failed to allocate page buffer for verifying erase at 0x%08x. Assuming it worked\n", jeb->offset);
292 		} else {
293 			__u32 ofs = jeb->offset;
294 
295 			D1(printk(KERN_DEBUG "Verifying erase at 0x%08x\n", jeb->offset));
296 			while(ofs < jeb->offset + c->sector_size) {
297 				__u32 readlen = min((__u32)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
298 				int i;
299 
300 				ret = c->mtd->read(c->mtd, ofs, readlen, &retlen, ebuf);
301 				if (ret < 0) {
302 					printk(KERN_WARNING "Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n", ofs, ret);
303 					goto bad;
304 				}
305 				if (retlen != readlen) {
306 					printk(KERN_WARNING "Short read from newly-erased block at 0x%08x. Wanted %d, got %d\n", ofs, readlen, retlen);
307 					goto bad;
308 				}
309 				for (i=0; i<readlen; i += sizeof(unsigned long)) {
310 					/* It's OK. We know it's properly aligned */
311 					unsigned long datum = *(unsigned long *)(&ebuf[i]);
312 					if (datum + 1) {
313 						printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08x\n", datum, ofs + i);
314 					bad:
315 						jffs2_free_raw_node_ref(marker_ref);
316 						kfree(ebuf);
317 					bad2:
318 						spin_lock_bh(&c->erase_completion_lock);
319 						c->erasing_size -= c->sector_size;
320 						c->bad_size += c->sector_size;
321 
322 						list_add_tail(&jeb->list, &c->bad_list);
323 						c->nr_erasing_blocks--;
324 						spin_unlock_bh(&c->erase_completion_lock);
325 						wake_up(&c->erase_wait);
326 						return;
327 					}
328 				}
329 				ofs += readlen;
330 			}
331 			kfree(ebuf);
332 		}
333 
334 		/* Write the erase complete marker */
335 		D1(printk(KERN_DEBUG "Writing erased marker to block at 0x%08x\n", jeb->offset));
336 		ret = c->mtd->write(c->mtd, jeb->offset, sizeof(marker), &retlen, (char *)&marker);
337 		if (ret) {
338 			printk(KERN_WARNING "Write clean marker to block at 0x%08x failed: %d\n",
339 			       jeb->offset, ret);
340 			goto bad2;
341 		}
342 		if (retlen != sizeof(marker)) {
343 			printk(KERN_WARNING "Short write to newly-erased block at 0x%08x: Wanted %d, got %d\n",
344 			       jeb->offset, sizeof(marker), retlen);
345 			goto bad2;
346 		}
347 
348 		marker_ref->next_in_ino = NULL;
349 		marker_ref->next_phys = NULL;
350 		marker_ref->flash_offset = jeb->offset;
351 		marker_ref->totlen = PAD(sizeof(marker));
352 
353 		jeb->first_node = jeb->last_node = marker_ref;
354 
355 		jeb->free_size = c->sector_size - marker_ref->totlen;
356 		jeb->used_size = marker_ref->totlen;
357 		jeb->dirty_size = 0;
358 
359 		spin_lock_bh(&c->erase_completion_lock);
360 		c->erasing_size -= c->sector_size;
361 		c->free_size += jeb->free_size;
362 		c->used_size += jeb->used_size;
363 
364 		ACCT_SANITY_CHECK(c,jeb);
365 		ACCT_PARANOIA_CHECK(jeb);
366 
367 		list_add_tail(&jeb->list, &c->free_list);
368 		c->nr_erasing_blocks--;
369 		c->nr_free_blocks++;
370 		wake_up(&c->erase_wait);
371 	}
372 	spin_unlock_bh(&c->erase_completion_lock);
373 }
374