예제 #1
0
파일: scan.c 프로젝트: NieHao/Tomato-RAF
/* We're pointing at the first empty word on the flash. Scan and account for the whole dirty region */
static int jffs2_scan_empty(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, __u32 *startofs, int *noise)
{
	__u32 *buf;
	__u32 scanlen = (jeb->offset + c->sector_size) - *startofs;
	__u32 curofs = *startofs;
	
	buf = kmalloc(min((__u32)PAGE_SIZE, scanlen), GFP_KERNEL);
	if (!buf) {
		printk(KERN_WARNING "Scan buffer allocation failed\n");
		return -ENOMEM;
	}
	while(scanlen) {
		ssize_t retlen;
		int ret, i;
		
		ret = c->mtd->read(c->mtd, curofs, min((__u32)PAGE_SIZE, scanlen), &retlen, (char *)buf);
		if(ret) {
			D1(printk(KERN_WARNING "jffs2_scan_empty(): Read 0x%x bytes at 0x%08x returned %d\n", min((__u32)PAGE_SIZE, scanlen), curofs, ret));
			kfree(buf);
			return ret;
		}
		if (retlen < 4) {
			D1(printk(KERN_WARNING "Eep. too few bytes read in scan_empty()\n"));
			kfree(buf);
			return -EIO;
		}
		for (i=0; i<(retlen / 4); i++) {
			if (buf[i] != 0xffffffff) {
				curofs += i*4;

				noisy_printk(noise, "jffs2_scan_empty(): Empty block at 0x%08x ends at 0x%08x (with 0x%08x)! Marking dirty\n", *startofs, curofs, buf[i]);
				DIRTY_SPACE(curofs - (*startofs));
				*startofs = curofs;
				kfree(buf);
				return 0;
			}
		}
		scanlen -= retlen&~3;
		curofs += retlen&~3;
	}

	D1(printk(KERN_DEBUG "Empty flash detected from 0x%08x to 0x%08x\n", *startofs, curofs));
	kfree(buf);
	*startofs = curofs;
	return 0;
}
예제 #2
0
/* Called with 'buf_size == 0' if buf is in fact a pointer _directly_ into
   the flash, XIP-style */
static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
				  unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) {
	struct jffs2_unknown_node *node;
	struct jffs2_unknown_node crcnode;
	uint32_t ofs, prevofs, max_ofs;
	uint32_t hdr_crc, buf_ofs, buf_len;
	int err;
	int noise = 0;


#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
	int cleanmarkerfound = 0;
#endif

	ofs = jeb->offset;
	prevofs = jeb->offset - 1;

	D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));

#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
	if (c->mtd->type == MTD_NANDFLASH) {
		int ret;

		if (c->mtd->block_isbad(c->mtd, jeb->offset))
			return BLK_STATE_BADBLOCK;

		if (jffs2_cleanmarker_oob(c)) {
			ret = jffs2_check_nand_cleanmarker(c, jeb);
			D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n", ret));

			/* Even if it's not found, we still scan to see
			   if the block is empty. We use this information
			   to decide whether to erase it or not. */
			switch (ret) {
			case 0:		cleanmarkerfound = 1; break;
			case 1: 	break;
			default: 	return ret;
			}
		}
	}
#endif

	if (jffs2_sum_active()) {
		struct jffs2_sum_marker *sm;
		void *sumptr = NULL;
		uint32_t sumlen;
	      
		if (!buf_size) {
			/* XIP case. Just look, point at the summary if it's there */
			sm = (void *)buf + c->sector_size - sizeof(*sm);
			if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) {
				sumptr = buf + je32_to_cpu(sm->offset);
				sumlen = c->sector_size - je32_to_cpu(sm->offset);
			}
		} else {
			/* If NAND flash, read a whole page of it. Else just the end */
			if (c->wbuf_pagesize)
				buf_len = c->wbuf_pagesize;
			else
				buf_len = sizeof(*sm);

			/* Read as much as we want into the _end_ of the preallocated buffer */
			err = jffs2_fill_scan_buf(c, buf + buf_size - buf_len, 
						  jeb->offset + c->sector_size - buf_len,
						  buf_len);				
			if (err)
				return err;

			sm = (void *)buf + buf_size - sizeof(*sm);
			if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) {
				sumlen = c->sector_size - je32_to_cpu(sm->offset);
				sumptr = buf + buf_size - sumlen;

				/* Now, make sure the summary itself is available */
				if (sumlen > buf_size) {
					/* Need to kmalloc for this. */
					sumptr = kmalloc(sumlen, GFP_KERNEL);
					if (!sumptr)
						return -ENOMEM;
					memcpy(sumptr + sumlen - buf_len, buf + buf_size - buf_len, buf_len);
				}
				if (buf_len < sumlen) {
					/* Need to read more so that the entire summary node is present */
					err = jffs2_fill_scan_buf(c, sumptr, 
								  jeb->offset + c->sector_size - sumlen,
								  sumlen - buf_len);				
					if (err)
						return err;
				}
			}

		}

		if (sumptr) {
			err = jffs2_sum_scan_sumnode(c, jeb, sumptr, sumlen, &pseudo_random);

			if (buf_size && sumlen > buf_size)
				kfree(sumptr);
			/* If it returns with a real error, bail. 
			   If it returns positive, that's a block classification
			   (i.e. BLK_STATE_xxx) so return that too.
			   If it returns zero, fall through to full scan. */
			if (err)
				return err;
		}
	}

	buf_ofs = jeb->offset;

	if (!buf_size) {
		/* This is the XIP case -- we're reading _directly_ from the flash chip */
		buf_len = c->sector_size;
	} else {
		buf_len = EMPTY_SCAN_SIZE(c->sector_size);
		err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
		if (err)
			return err;
	}

	/* We temporarily use 'ofs' as a pointer into the buffer/jeb */
	ofs = 0;
	max_ofs = EMPTY_SCAN_SIZE(c->sector_size);
	/* Scan only EMPTY_SCAN_SIZE of 0xFF before declaring it's empty */
	while(ofs < max_ofs && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
		ofs += 4;

	if (ofs == max_ofs) {
#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
		if (jffs2_cleanmarker_oob(c)) {
			/* scan oob, take care of cleanmarker */
			int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound);
			D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret));
			switch (ret) {
			case 0:		return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF;
			case 1: 	return BLK_STATE_ALLDIRTY;
			default: 	return ret;
			}
		}
#endif
		D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
		if (c->cleanmarker_size == 0)
			return BLK_STATE_CLEANMARKER;	/* don't bother with re-erase */
		else
			return BLK_STATE_ALLFF;	/* OK to erase if all blocks are like this */
	}
	if (ofs) {
		D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset,
			  jeb->offset + ofs));
		if ((err = jffs2_prealloc_raw_node_refs(c, jeb, 1)))
			return err;
		if ((err = jffs2_scan_dirty_space(c, jeb, ofs)))
			return err;
	}

	/* Now ofs is a complete physical flash offset as it always was... */
	ofs += jeb->offset;

	noise = 10;

	dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset);

scan_more:
	while(ofs < jeb->offset + c->sector_size) {

		jffs2_dbg_acct_paranoia_check_nolock(c, jeb);

		/* Make sure there are node refs available for use */
		err = jffs2_prealloc_raw_node_refs(c, jeb, 2);
		if (err)
			return err;

		cond_resched();

		if (ofs & 3) {
			printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
			ofs = PAD(ofs);
			continue;
		}
		if (ofs == prevofs) {
			printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		prevofs = ofs;

		if (jeb->offset + c->sector_size < ofs + sizeof(*node)) {
			D1(printk(KERN_DEBUG "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n", sizeof(struct jffs2_unknown_node),
				  jeb->offset, c->sector_size, ofs, sizeof(*node)));
			if ((err = jffs2_scan_dirty_space(c, jeb, (jeb->offset + c->sector_size)-ofs)))
				return err;
			break;
		}

		if (buf_ofs + buf_len < ofs + sizeof(*node)) {
			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
			D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n",
				  sizeof(struct jffs2_unknown_node), buf_len, ofs));
			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
			if (err)
				return err;
			buf_ofs = ofs;
		}

		node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs];

		if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
			uint32_t inbuf_ofs;
			uint32_t empty_start, scan_end;

			empty_start = ofs;
			ofs += 4;
			scan_end = min_t(uint32_t, EMPTY_SCAN_SIZE(c->sector_size)/8, buf_len);

			D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs));
		more_empty:
			inbuf_ofs = ofs - buf_ofs;
			while (inbuf_ofs < scan_end) {
				if (unlikely(*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff)) {
					printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n",
					       empty_start, ofs);
					if ((err = jffs2_scan_dirty_space(c, jeb, ofs-empty_start)))
						return err;
					goto scan_more;
				}

				inbuf_ofs+=4;
				ofs += 4;
			}
			/* Ran off end. */
			D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs));

			/* If we're only checking the beginning of a block with a cleanmarker,
			   bail now */
			if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) &&
			    c->cleanmarker_size && !jeb->dirty_size && !ref_next(jeb->first_node)) {
				D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size)));
				return BLK_STATE_CLEANMARKER;
			}
			if (!buf_size && (scan_end != buf_len)) {/* XIP/point case */
				scan_end = buf_len;
				goto more_empty;
			}
			
			/* See how much more there is to read in this eraseblock... */
			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
			if (!buf_len) {
				/* No more to read. Break out of main loop without marking
				   this range of empty space as dirty (because it's not) */
				D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n",
					  empty_start));
				break;
			}
			/* point never reaches here */
			scan_end = buf_len;
			D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs));
			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
			if (err)
				return err;
			buf_ofs = ofs;
			goto more_empty;
		}

		if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) {
			printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) {
			D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs));
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) {
			printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
			printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) {
			/* OK. We're out of possibilities. Whinge and move on */
			noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n",
				     JFFS2_MAGIC_BITMASK, ofs,
				     je16_to_cpu(node->magic));
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		/* We seem to have a node of sorts. Check the CRC */
		crcnode.magic = node->magic;
		crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE);
		crcnode.totlen = node->totlen;
		hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4);

		if (hdr_crc != je32_to_cpu(node->hdr_crc)) {
			noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n",
				     ofs, je16_to_cpu(node->magic),
				     je16_to_cpu(node->nodetype),
				     je32_to_cpu(node->totlen),
				     je32_to_cpu(node->hdr_crc),
				     hdr_crc);
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}

		if (ofs + je32_to_cpu(node->totlen) > jeb->offset + c->sector_size) {
			/* Eep. Node goes over the end of the erase block. */
			printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
			       ofs, je32_to_cpu(node->totlen));
			printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}

		if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
			/* Wheee. This is an obsoleted node */
			D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs));
			if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
				return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			continue;
		}

		switch(je16_to_cpu(node->nodetype)) {
		case JFFS2_NODETYPE_INODE:
			if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  sizeof(struct jffs2_raw_inode), buf_len, ofs));
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s);
			if (err) return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		case JFFS2_NODETYPE_DIRENT:
			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  je32_to_cpu(node->totlen), buf_len, ofs));
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s);
			if (err) return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

#ifdef CONFIG_JFFS2_FS_XATTR
		case JFFS2_NODETYPE_XATTR:
			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				D1(printk(KERN_DEBUG "Fewer than %d bytes (xattr node)"
					  " left to end of buf. Reading 0x%x at 0x%08x\n",
					  je32_to_cpu(node->totlen), buf_len, ofs));
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_xattr_node(c, jeb, (void *)node, ofs, s);
			if (err)
				return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;
		case JFFS2_NODETYPE_XREF:
			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				D1(printk(KERN_DEBUG "Fewer than %d bytes (xref node)"
					  " left to end of buf. Reading 0x%x at 0x%08x\n",
					  je32_to_cpu(node->totlen), buf_len, ofs));
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_xref_node(c, jeb, (void *)node, ofs, s);
			if (err)
				return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;
#endif	/* CONFIG_JFFS2_FS_XATTR */

		case JFFS2_NODETYPE_CLEANMARKER:
			D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs));
			if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {
				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n",
				       ofs, je32_to_cpu(node->totlen), c->cleanmarker_size);
				if ((err = jffs2_scan_dirty_space(c, jeb, PAD(sizeof(struct jffs2_unknown_node)))))
					return err;
				ofs += PAD(sizeof(struct jffs2_unknown_node));
			} else if (jeb->first_node) {
				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
				if ((err = jffs2_scan_dirty_space(c, jeb, PAD(sizeof(struct jffs2_unknown_node)))))
					return err;
				ofs += PAD(sizeof(struct jffs2_unknown_node));
			} else {
				jffs2_link_node_ref(c, jeb, ofs | REF_NORMAL, c->cleanmarker_size, NULL);

				ofs += PAD(c->cleanmarker_size);
			}
			break;

		case JFFS2_NODETYPE_PADDING:
			if (jffs2_sum_active())
				jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen));
			if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
				return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		default:
			switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) {
			case JFFS2_FEATURE_ROCOMPAT:
				printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
				c->flags |= JFFS2_SB_FLAG_RO;
				if (!(jffs2_is_readonly(c)))
					return -EROFS;
				if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
					return err;
				ofs += PAD(je32_to_cpu(node->totlen));
				break;

			case JFFS2_FEATURE_INCOMPAT:
				printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
				return -EINVAL;

			case JFFS2_FEATURE_RWCOMPAT_DELETE:
				D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
				if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
					return err;
				ofs += PAD(je32_to_cpu(node->totlen));
				break;

			case JFFS2_FEATURE_RWCOMPAT_COPY: {
				D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));

				jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, PAD(je32_to_cpu(node->totlen)), NULL);

				/* We can't summarise nodes we don't grok */
				jffs2_sum_disable_collecting(s);
				ofs += PAD(je32_to_cpu(node->totlen));
				break;
				}
			}
		}
	}

	if (jffs2_sum_active()) {
		if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) {
			dbg_summary("There is not enough space for "
				"summary information, disabling for this jeb!\n");
			jffs2_sum_disable_collecting(s);
		}
	}

	D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x, wasted 0x%08x\n",
		  jeb->offset,jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size, jeb->wasted_size));
	
	/* mark_node_obsolete can add to wasted !! */
	if (jeb->wasted_size) {
		jeb->dirty_size += jeb->wasted_size;
		c->dirty_size += jeb->wasted_size;
		c->wasted_size -= jeb->wasted_size;
		jeb->wasted_size = 0;
	}

	return jffs2_scan_classify_jeb(c, jeb);
}
예제 #3
0
파일: scan.c 프로젝트: LucidOne/Rovio
static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
				  unsigned char *buf, uint32_t buf_size) {
	struct jffs2_unknown_node *node;
	struct jffs2_unknown_node crcnode;
	uint32_t ofs, prevofs;
	uint32_t hdr_crc, buf_ofs, buf_len;
	int err;
	int noise = 0;
	int wasempty = 0;
	uint32_t empty_start = 0;
#ifdef CONFIG_JFFS2_FS_NAND
	int cleanmarkerfound = 0;
#endif

	ofs = jeb->offset;
	prevofs = jeb->offset - 1;

	D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));

#ifdef CONFIG_JFFS2_FS_NAND
	if (jffs2_cleanmarker_oob(c)) {
		int ret = jffs2_check_nand_cleanmarker(c, jeb);
		D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret));
		/* Even if it's not found, we still scan to see
		   if the block is empty. We use this information
		   to decide whether to erase it or not. */
		switch (ret) {
		case 0:		cleanmarkerfound = 1; break;
		case 1: 	break;
		case 2: 	return BLK_STATE_BADBLOCK;
		case 3:		return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */
		default: 	return ret;
		}
	}
#endif
	buf_ofs = jeb->offset;

	if (!buf_size) {
		buf_len = c->sector_size;
	} else {
		buf_len = EMPTY_SCAN_SIZE;
		err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
		if (err)
			return err;
	}
	
	/* We temporarily use 'ofs' as a pointer into the buffer/jeb */
	ofs = 0;

	/* Scan only 4KiB of 0xFF before declaring it's empty */
	while(ofs < EMPTY_SCAN_SIZE && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
		ofs += 4;

	if (ofs == EMPTY_SCAN_SIZE) {
#ifdef CONFIG_JFFS2_FS_NAND
		if (jffs2_cleanmarker_oob(c)) {
			/* scan oob, take care of cleanmarker */
			int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound);
			D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret));
			switch (ret) {
			case 0:		return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF;
			case 1: 	return BLK_STATE_ALLDIRTY;
			case 2: 	return BLK_STATE_BADBLOCK; /* case 2/3 are paranoia checks */
			case 3:		return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */
			default: 	return ret;
			}
		}
#endif
		D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
		return BLK_STATE_ALLFF;	/* OK to erase if all blocks are like this */
	}
	if (ofs) {
		D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset,
			  jeb->offset + ofs));
		DIRTY_SPACE(ofs);
	}

	/* Now ofs is a complete physical flash offset as it always was... */
	ofs += jeb->offset;

	noise = 10;

	while(ofs < jeb->offset + c->sector_size) {

		D1(ACCT_PARANOIA_CHECK(jeb));

		cond_resched();

		if (ofs & 3) {
			printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
			ofs = (ofs+3)&~3;
			continue;
		}
		if (ofs == prevofs) {
			printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		prevofs = ofs;

		if (jeb->offset + c->sector_size < ofs + sizeof(*node)) {
			D1(printk(KERN_DEBUG "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n", sizeof(struct jffs2_unknown_node),
				  jeb->offset, c->sector_size, ofs, sizeof(*node)));
			DIRTY_SPACE((jeb->offset + c->sector_size)-ofs);
			break;
		}

		if (buf_ofs + buf_len < ofs + sizeof(*node)) {
			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
			D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n",
				  sizeof(struct jffs2_unknown_node), buf_len, ofs));
			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
			if (err)
				return err;
			buf_ofs = ofs;
		}

		node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs];

		if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
			uint32_t inbuf_ofs = ofs - buf_ofs + 4;
			uint32_t scanend;

			empty_start = ofs;
			ofs += 4;

			/* If scanning empty space after only a cleanmarker, don't
			   bother scanning the whole block */
			if (unlikely(empty_start == jeb->offset + c->cleanmarker_size &&
				     jeb->offset + EMPTY_SCAN_SIZE < buf_ofs + buf_len))
				scanend = jeb->offset + EMPTY_SCAN_SIZE - buf_ofs;
			else
				scanend = buf_len;

			D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs));
			while (inbuf_ofs < scanend) {
				if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff)
					goto emptyends;

				inbuf_ofs+=4;
				ofs += 4;
			}
			/* Ran off end. */
			D1(printk(KERN_DEBUG "Empty flash ends normally at 0x%08x\n", ofs));

			if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) && 
			    !jeb->first_node->next_in_ino && !jeb->dirty_size)
				return BLK_STATE_CLEANMARKER;
			wasempty = 1;
			continue;
		} else if (wasempty) {
		emptyends:
			printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n", empty_start, ofs);
			DIRTY_SPACE(ofs-empty_start);
			wasempty = 0;
			continue;
		}

		if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) {
			printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) {
			D1(printk(KERN_DEBUG "Empty bitmask at 0x%08x\n", ofs));
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) {
			printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
			printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) {
			/* OK. We're out of possibilities. Whinge and move on */
			noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", 
				     JFFS2_MAGIC_BITMASK, ofs, 
				     je16_to_cpu(node->magic));
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		/* We seem to have a node of sorts. Check the CRC */
		crcnode.magic = node->magic;
		crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE);
		crcnode.totlen = node->totlen;
		hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4);

		if (hdr_crc != je32_to_cpu(node->hdr_crc)) {
			noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n",
				     ofs, je16_to_cpu(node->magic),
				     je16_to_cpu(node->nodetype), 
				     je32_to_cpu(node->totlen),
				     je32_to_cpu(node->hdr_crc),
				     hdr_crc);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}

		if (ofs + je32_to_cpu(node->totlen) > 
		    jeb->offset + c->sector_size) {
			/* Eep. Node goes over the end of the erase block. */
			printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
			       ofs, je32_to_cpu(node->totlen));
			printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}

		if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
			/* Wheee. This is an obsoleted node */
			D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs));
			DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
			ofs += PAD(je32_to_cpu(node->totlen));
			continue;
		}

		switch(je16_to_cpu(node->nodetype)) {
		case JFFS2_NODETYPE_INODE:
			if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  sizeof(struct jffs2_raw_inode), buf_len, ofs));
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs);
			if (err) return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;
			
		case JFFS2_NODETYPE_DIRENT:
			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  je32_to_cpu(node->totlen), buf_len, ofs));
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs);
			if (err) return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		case JFFS2_NODETYPE_CLEANMARKER:
			D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs));
			if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {
				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", 
				       ofs, je32_to_cpu(node->totlen), c->cleanmarker_size);
				DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
				ofs += PAD(sizeof(struct jffs2_unknown_node));
			} else if (jeb->first_node) {
				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
				DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
				ofs += PAD(sizeof(struct jffs2_unknown_node));
			} else {
				struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref();
				if (!marker_ref) {
					printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n");
					return -ENOMEM;
				}
				marker_ref->next_in_ino = NULL;
				marker_ref->next_phys = NULL;
				marker_ref->flash_offset = ofs | REF_NORMAL;
				marker_ref->totlen = c->cleanmarker_size;
				jeb->first_node = jeb->last_node = marker_ref;
			     
				USED_SPACE(PAD(c->cleanmarker_size));
				ofs += PAD(c->cleanmarker_size);
			}
			break;

		case JFFS2_NODETYPE_PADDING:
			DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		default:
			switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) {
			case JFFS2_FEATURE_ROCOMPAT:
				printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
			        c->flags |= JFFS2_SB_FLAG_RO;
				if (!(jffs2_is_readonly(c)))
					return -EROFS;
				DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
				ofs += PAD(je32_to_cpu(node->totlen));
				break;

			case JFFS2_FEATURE_INCOMPAT:
				printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
				return -EINVAL;

			case JFFS2_FEATURE_RWCOMPAT_DELETE:
				D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
				DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
				ofs += PAD(je32_to_cpu(node->totlen));
				break;

			case JFFS2_FEATURE_RWCOMPAT_COPY:
				D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
				USED_SPACE(PAD(je32_to_cpu(node->totlen)));
				ofs += PAD(je32_to_cpu(node->totlen));
				break;
			}
		}
	}


	D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, 
		  jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size));

	/* mark_node_obsolete can add to wasted !! */
	if (jeb->wasted_size) {
		jeb->dirty_size += jeb->wasted_size;
		c->dirty_size += jeb->wasted_size;
		c->wasted_size -= jeb->wasted_size;
		jeb->wasted_size = 0;
	}

	if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size 
		&& (!jeb->first_node || jeb->first_node->next_in_ino) )
		return BLK_STATE_CLEANMARKER;
		
	/* move blocks with max 4 byte dirty space to cleanlist */	
	else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) {
		c->dirty_size -= jeb->dirty_size;
		c->wasted_size += jeb->dirty_size; 
		jeb->wasted_size += jeb->dirty_size;
		jeb->dirty_size = 0;
		return BLK_STATE_CLEAN;
	} else if (jeb->used_size || jeb->unchecked_size)
		return BLK_STATE_PARTDIRTY;
	else
		return BLK_STATE_ALLDIRTY;
}
예제 #4
0
파일: scan.c 프로젝트: NieHao/Tomato-RAF
static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb) {
	struct jffs2_unknown_node node;
	__u32 ofs, prevofs;
	__u32 hdr_crc, nodetype;
	int err;
	int noise = 0;

	ofs = jeb->offset;
	prevofs = jeb->offset - 1;

	D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));

	err = jffs2_scan_empty(c, jeb, &ofs, &noise);
	if (err) return err;
	if (ofs == jeb->offset + c->sector_size) {
		D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
		return 1;	/* special return code */
	}
	
	noise = 10;

	while(ofs < jeb->offset + c->sector_size) {
		ssize_t retlen;
		unsigned char *buf = (unsigned char *) &node;
		ACCT_PARANOIA_CHECK(jeb);
		
		if (ofs & 3) {
			printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
			ofs = (ofs+3)&~3;
			continue;
		}
		if (ofs == prevofs) {
			printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		prevofs = ofs;
		
		if (jeb->offset + c->sector_size < ofs + sizeof(node)) {
			D1(printk(KERN_DEBUG "Fewer than %d bytes left to end of block. Not reading\n", sizeof(struct jffs2_unknown_node)));
			DIRTY_SPACE((jeb->offset + c->sector_size)-ofs);
			break;
		}

		err = c->mtd->read(c->mtd, ofs, sizeof(node), &retlen, buf);
		if ((buf[0] == 0xde) &&
			(buf[1] == 0xad) &&
			(buf[2] == 0xc0) &&
			(buf[3] == 0xde)) {
				
			/* end of filesystem. erase everything after this point */
			c->flags |= (1 << 7);
			printk("jffs2_scan_eraseblock(): End of filesystem marker found at 0x%x\n", jeb->offset);
		
			return 1;
		}
		if (err) {
			D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", sizeof(node), ofs, err));
			return err;
		}
		if (retlen < sizeof(node)) {
			D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%x bytes\n", ofs, retlen));
			DIRTY_SPACE(retlen);
			ofs += retlen;
			continue;
		}

		if (node.magic == JFFS2_EMPTY_BITMASK && node.nodetype == JFFS2_EMPTY_BITMASK) {
			D1(printk(KERN_DEBUG "Found empty flash at 0x%x\n", ofs));
			err = jffs2_scan_empty(c, jeb, &ofs, &noise);
			if (err) return err;
			continue;
		}

		if (ofs == jeb->offset && node.magic == KSAMTIB_CIGAM_2SFFJ) {
			printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (node.magic == JFFS2_DIRTY_BITMASK) {
			D1(printk(KERN_DEBUG "Empty bitmask at 0x%08x\n", ofs));
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (node.magic == JFFS2_OLD_MAGIC_BITMASK) {
			printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
			printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (node.magic != JFFS2_MAGIC_BITMASK) {
			/* OK. We're out of possibilities. Whinge and move on */
			noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", JFFS2_MAGIC_BITMASK, ofs, node.magic);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		/* We seem to have a node of sorts. Check the CRC */
		nodetype = node.nodetype;
		node.nodetype |= JFFS2_NODE_ACCURATE;
		hdr_crc = crc32(0, &node, sizeof(node)-4);
		node.nodetype = nodetype;
		if (hdr_crc != node.hdr_crc) {
			noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n",
				     ofs, node.magic, node.nodetype, node.totlen, node.hdr_crc, hdr_crc);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}

		if (ofs + node.totlen > jeb->offset + c->sector_size) {
			/* Eep. Node goes over the end of the erase block. */
			printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
			       ofs, node.totlen);
			printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}

		switch(node.nodetype | JFFS2_NODE_ACCURATE) {
		case JFFS2_NODETYPE_INODE:
			err = jffs2_scan_inode_node(c, jeb, &ofs);
			if (err) return err;
			break;
			
		case JFFS2_NODETYPE_DIRENT:
			err = jffs2_scan_dirent_node(c, jeb, &ofs);
			if (err) return err;
			break;

		case JFFS2_NODETYPE_CLEANMARKER:
			if (node.totlen != sizeof(struct jffs2_unknown_node)) {
				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", 
				       ofs, node.totlen, sizeof(struct jffs2_unknown_node));
				DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
			} else if (jeb->first_node) {
				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
				DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
				ofs += PAD(sizeof(struct jffs2_unknown_node));
				continue;
			} else {
				struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref();
				if (!marker_ref) {
					printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n");
					return -ENOMEM;
				}
				marker_ref->next_in_ino = NULL;
				marker_ref->next_phys = NULL;
				marker_ref->flash_offset = ofs;
				marker_ref->totlen = sizeof(struct jffs2_unknown_node);
				jeb->first_node = jeb->last_node = marker_ref;
			     
				USED_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
			}
			ofs += PAD(sizeof(struct jffs2_unknown_node));
			break;

		default:
			switch (node.nodetype & JFFS2_COMPAT_MASK) {
			case JFFS2_FEATURE_ROCOMPAT:
				printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", node.nodetype, ofs);
			        c->flags |= JFFS2_SB_FLAG_RO;
				if (!(OFNI_BS_2SFFJ(c)->s_flags & MS_RDONLY))
					return -EROFS;
				DIRTY_SPACE(PAD(node.totlen));
				ofs += PAD(node.totlen);
				continue;

			case JFFS2_FEATURE_INCOMPAT:
				printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", node.nodetype, ofs);
				return -EINVAL;

			case JFFS2_FEATURE_RWCOMPAT_DELETE:
				printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", node.nodetype, ofs);
				DIRTY_SPACE(PAD(node.totlen));
				ofs += PAD(node.totlen);
				break;

			case JFFS2_FEATURE_RWCOMPAT_COPY:
				printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", node.nodetype, ofs);
				USED_SPACE(PAD(node.totlen));
				ofs += PAD(node.totlen);
				break;
			}
		}
	}
	D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, used 0x%08x\n", jeb->offset, 
		  jeb->free_size, jeb->dirty_size, jeb->used_size));
	return 0;
}
예제 #5
0
static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
				  unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) {
	struct jffs2_unknown_node *node;
	struct jffs2_unknown_node crcnode;
	uint32_t ofs, prevofs, max_ofs;
	uint32_t hdr_crc, buf_ofs, buf_len;
	int err;
	int noise = 0;


#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
	int cleanmarkerfound = 0;
#endif

	ofs = jeb->offset;
	prevofs = jeb->offset - 1;

	jffs2_dbg(1, "%s(): Scanning block at 0x%x\n", __func__, ofs);

#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
	if (jffs2_cleanmarker_oob(c)) {
		int ret;

		if (mtd_block_isbad(c->mtd, jeb->offset))
			return BLK_STATE_BADBLOCK;

		ret = jffs2_check_nand_cleanmarker(c, jeb);
		jffs2_dbg(2, "jffs_check_nand_cleanmarker returned %d\n", ret);

		switch (ret) {
		case 0:		cleanmarkerfound = 1; break;
		case 1: 	break;
		default: 	return ret;
		}
	}
#endif

	if (jffs2_sum_active()) {
		struct jffs2_sum_marker *sm;
		void *sumptr = NULL;
		uint32_t sumlen;
	      
		if (!buf_size) {
			
			sm = (void *)buf + c->sector_size - sizeof(*sm);
			if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) {
				sumptr = buf + je32_to_cpu(sm->offset);
				sumlen = c->sector_size - je32_to_cpu(sm->offset);
			}
		} else {
			
			if (c->wbuf_pagesize)
				buf_len = c->wbuf_pagesize;
			else
				buf_len = sizeof(*sm);

			
			err = jffs2_fill_scan_buf(c, buf + buf_size - buf_len, 
						  jeb->offset + c->sector_size - buf_len,
						  buf_len);				
			if (err)
				return err;

			sm = (void *)buf + buf_size - sizeof(*sm);
			if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) {
				sumlen = c->sector_size - je32_to_cpu(sm->offset);
				sumptr = buf + buf_size - sumlen;

				
				if (sumlen > buf_size) {
					
					sumptr = kmalloc(sumlen, GFP_KERNEL);
					if (!sumptr)
						return -ENOMEM;
					memcpy(sumptr + sumlen - buf_len, buf + buf_size - buf_len, buf_len);
				}
				if (buf_len < sumlen) {
					
					err = jffs2_fill_scan_buf(c, sumptr, 
								  jeb->offset + c->sector_size - sumlen,
								  sumlen - buf_len);				
					if (err)
						return err;
				}
			}

		}

		if (sumptr) {
			err = jffs2_sum_scan_sumnode(c, jeb, sumptr, sumlen, &pseudo_random);

			if (buf_size && sumlen > buf_size)
				kfree(sumptr);
			if (err)
				return err;
		}
	}

	buf_ofs = jeb->offset;

	if (!buf_size) {
		
		buf_len = c->sector_size;
	} else {
		buf_len = EMPTY_SCAN_SIZE(c->sector_size);
		err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
		if (err)
			return err;
	}

	
	ofs = 0;
	max_ofs = EMPTY_SCAN_SIZE(c->sector_size);
	
	while(ofs < max_ofs && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
		ofs += 4;

	if (ofs == max_ofs) {
#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
		if (jffs2_cleanmarker_oob(c)) {
			
			int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound);
			jffs2_dbg(2, "jffs2_check_oob_empty returned %d\n",
				  ret);
			switch (ret) {
			case 0:		return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF;
			case 1: 	return BLK_STATE_ALLDIRTY;
			default: 	return ret;
			}
		}
#endif
		jffs2_dbg(1, "Block at 0x%08x is empty (erased)\n",
			  jeb->offset);
		if (c->cleanmarker_size == 0)
			return BLK_STATE_CLEANMARKER;	
		else
			return BLK_STATE_ALLFF;	
	}
	if (ofs) {
		jffs2_dbg(1, "Free space at %08x ends at %08x\n", jeb->offset,
			  jeb->offset + ofs);
		if ((err = jffs2_prealloc_raw_node_refs(c, jeb, 1)))
			return err;
		if ((err = jffs2_scan_dirty_space(c, jeb, ofs)))
			return err;
	}

	
	ofs += jeb->offset;

	noise = 10;

	dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset);

scan_more:
	while(ofs < jeb->offset + c->sector_size) {

		jffs2_dbg_acct_paranoia_check_nolock(c, jeb);

		
		err = jffs2_prealloc_raw_node_refs(c, jeb, 2);
		if (err)
			return err;

		cond_resched();

		if (ofs & 3) {
			pr_warn("Eep. ofs 0x%08x not word-aligned!\n", ofs);
			ofs = PAD(ofs);
			continue;
		}
		if (ofs == prevofs) {
			pr_warn("ofs 0x%08x has already been seen. Skipping\n",
				ofs);
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		prevofs = ofs;

		if (jeb->offset + c->sector_size < ofs + sizeof(*node)) {
			jffs2_dbg(1, "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n",
				  sizeof(struct jffs2_unknown_node),
				  jeb->offset, c->sector_size, ofs,
				  sizeof(*node));
			if ((err = jffs2_scan_dirty_space(c, jeb, (jeb->offset + c->sector_size)-ofs)))
				return err;
			break;
		}

		if (buf_ofs + buf_len < ofs + sizeof(*node)) {
			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
			jffs2_dbg(1, "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n",
				  sizeof(struct jffs2_unknown_node),
				  buf_len, ofs);
			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
			if (err)
				return err;
			buf_ofs = ofs;
		}

		node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs];

		if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
			uint32_t inbuf_ofs;
			uint32_t empty_start, scan_end;

			empty_start = ofs;
			ofs += 4;
			scan_end = min_t(uint32_t, EMPTY_SCAN_SIZE(c->sector_size)/8, buf_len);

			jffs2_dbg(1, "Found empty flash at 0x%08x\n", ofs);
		more_empty:
			inbuf_ofs = ofs - buf_ofs;
			while (inbuf_ofs < scan_end) {
				if (unlikely(*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff)) {
					pr_warn("Empty flash at 0x%08x ends at 0x%08x\n",
						empty_start, ofs);
					if ((err = jffs2_scan_dirty_space(c, jeb, ofs-empty_start)))
						return err;
					goto scan_more;
				}

				inbuf_ofs+=4;
				ofs += 4;
			}
			
			jffs2_dbg(1, "Empty flash to end of buffer at 0x%08x\n",
				  ofs);

			if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) &&
			    c->cleanmarker_size && !jeb->dirty_size && !ref_next(jeb->first_node)) {
				jffs2_dbg(1, "%d bytes at start of block seems clean... assuming all clean\n",
					  EMPTY_SCAN_SIZE(c->sector_size));
				return BLK_STATE_CLEANMARKER;
			}
			if (!buf_size && (scan_end != buf_len)) {
				scan_end = buf_len;
				goto more_empty;
			}
			
			
			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
			if (!buf_len) {
				jffs2_dbg(1, "Empty flash at %08x runs to end of block. Treating as free_space\n",
					  empty_start);
				break;
			}
			
			scan_end = buf_len;
			jffs2_dbg(1, "Reading another 0x%x at 0x%08x\n",
				  buf_len, ofs);
			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
			if (err)
				return err;
			buf_ofs = ofs;
			goto more_empty;
		}

		if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) {
			pr_warn("Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n",
				ofs);
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) {
			jffs2_dbg(1, "Dirty bitmask at 0x%08x\n", ofs);
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) {
			pr_warn("Old JFFS2 bitmask found at 0x%08x\n", ofs);
			pr_warn("You cannot use older JFFS2 filesystems with newer kernels\n");
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) {
			
			noisy_printk(&noise, "%s(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n",
				     __func__,
				     JFFS2_MAGIC_BITMASK, ofs,
				     je16_to_cpu(node->magic));
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}
		
		crcnode.magic = node->magic;
		crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE);
		crcnode.totlen = node->totlen;
		hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4);

		if (hdr_crc != je32_to_cpu(node->hdr_crc)) {
			noisy_printk(&noise, "%s(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n",
				     __func__,
				     ofs, je16_to_cpu(node->magic),
				     je16_to_cpu(node->nodetype),
				     je32_to_cpu(node->totlen),
				     je32_to_cpu(node->hdr_crc),
				     hdr_crc);
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}

		if (ofs + je32_to_cpu(node->totlen) > jeb->offset + c->sector_size) {
			
			pr_warn("Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
				ofs, je32_to_cpu(node->totlen));
			pr_warn("Perhaps the file system was created with the wrong erase size?\n");
			if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
				return err;
			ofs += 4;
			continue;
		}

		if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
			
			jffs2_dbg(2, "Node at 0x%08x is obsolete. Skipping\n",
				  ofs);
			if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
				return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			continue;
		}

		switch(je16_to_cpu(node->nodetype)) {
		case JFFS2_NODETYPE_INODE:
			if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				jffs2_dbg(1, "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  sizeof(struct jffs2_raw_inode),
					  buf_len, ofs);
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s);
			if (err) return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		case JFFS2_NODETYPE_DIRENT:
			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				jffs2_dbg(1, "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  je32_to_cpu(node->totlen), buf_len,
					  ofs);
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s);
			if (err) return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

#ifdef CONFIG_JFFS2_FS_XATTR
		case JFFS2_NODETYPE_XATTR:
			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				jffs2_dbg(1, "Fewer than %d bytes (xattr node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  je32_to_cpu(node->totlen), buf_len,
					  ofs);
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_xattr_node(c, jeb, (void *)node, ofs, s);
			if (err)
				return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;
		case JFFS2_NODETYPE_XREF:
			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				jffs2_dbg(1, "Fewer than %d bytes (xref node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  je32_to_cpu(node->totlen), buf_len,
					  ofs);
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_xref_node(c, jeb, (void *)node, ofs, s);
			if (err)
				return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;
#endif	

		case JFFS2_NODETYPE_CLEANMARKER:
			jffs2_dbg(1, "CLEANMARKER node found at 0x%08x\n", ofs);
			if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {
				pr_notice("CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n",
					  ofs, je32_to_cpu(node->totlen),
					  c->cleanmarker_size);
				if ((err = jffs2_scan_dirty_space(c, jeb, PAD(sizeof(struct jffs2_unknown_node)))))
					return err;
				ofs += PAD(sizeof(struct jffs2_unknown_node));
			} else if (jeb->first_node) {
				pr_notice("CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n",
					  ofs, jeb->offset);
				if ((err = jffs2_scan_dirty_space(c, jeb, PAD(sizeof(struct jffs2_unknown_node)))))
					return err;
				ofs += PAD(sizeof(struct jffs2_unknown_node));
			} else {
				jffs2_link_node_ref(c, jeb, ofs | REF_NORMAL, c->cleanmarker_size, NULL);

				ofs += PAD(c->cleanmarker_size);
			}
			break;

		case JFFS2_NODETYPE_PADDING:
			if (jffs2_sum_active())
				jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen));
			if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
				return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		default:
			switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) {
			case JFFS2_FEATURE_ROCOMPAT:
				pr_notice("Read-only compatible feature node (0x%04x) found at offset 0x%08x\n",
					  je16_to_cpu(node->nodetype), ofs);
				c->flags |= JFFS2_SB_FLAG_RO;
				if (!(jffs2_is_readonly(c)))
					return -EROFS;
				if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
					return err;
				ofs += PAD(je32_to_cpu(node->totlen));
				break;

			case JFFS2_FEATURE_INCOMPAT:
				pr_notice("Incompatible feature node (0x%04x) found at offset 0x%08x\n",
					  je16_to_cpu(node->nodetype), ofs);
				return -EINVAL;

			case JFFS2_FEATURE_RWCOMPAT_DELETE:
				jffs2_dbg(1, "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n",
					  je16_to_cpu(node->nodetype), ofs);
				if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
					return err;
				ofs += PAD(je32_to_cpu(node->totlen));
				break;

			case JFFS2_FEATURE_RWCOMPAT_COPY: {
				jffs2_dbg(1, "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n",
					  je16_to_cpu(node->nodetype), ofs);

				jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, PAD(je32_to_cpu(node->totlen)), NULL);

				
				jffs2_sum_disable_collecting(s);
				ofs += PAD(je32_to_cpu(node->totlen));
				break;
				}
			}
		}
	}

	if (jffs2_sum_active()) {
		if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) {
			dbg_summary("There is not enough space for "
				"summary information, disabling for this jeb!\n");
			jffs2_sum_disable_collecting(s);
		}
	}

	jffs2_dbg(1, "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x, wasted 0x%08x\n",
		  jeb->offset, jeb->free_size, jeb->dirty_size,
		  jeb->unchecked_size, jeb->used_size, jeb->wasted_size);
	
	
	if (jeb->wasted_size) {
		jeb->dirty_size += jeb->wasted_size;
		c->dirty_size += jeb->wasted_size;
		c->wasted_size -= jeb->wasted_size;
		jeb->wasted_size = 0;
	}

	return jffs2_scan_classify_jeb(c, jeb);
}
예제 #6
0
파일: scan.c 프로젝트: mahyarmd/unifi-gpl
static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
				unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) {
	struct jffs2_unknown_node *node;
	struct jffs2_unknown_node crcnode;
	struct jffs2_sum_marker *sm;
	uint32_t ofs, prevofs;
	uint32_t hdr_crc, buf_ofs, buf_len;
	int err;
	int noise = 0;


#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
	int cleanmarkerfound = 0;
#endif

	ofs = jeb->offset;
	prevofs = jeb->offset - 1;

	D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));

#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
	if (jffs2_cleanmarker_oob(c)) {
		int ret = jffs2_check_nand_cleanmarker(c, jeb);
		D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret));
		/* Even if it's not found, we still scan to see
		   if the block is empty. We use this information
		   to decide whether to erase it or not. */
		switch (ret) {
		case 0:		cleanmarkerfound = 1; break;
		case 1: 	break;
		case 2: 	return BLK_STATE_BADBLOCK;
		case 3:		return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */
		default: 	return ret;
		}
	}
#endif

	if (jffs2_sum_active()) {
		sm = kmalloc(sizeof(struct jffs2_sum_marker), GFP_KERNEL);
		if (!sm) {
			return -ENOMEM;
		}

		err = jffs2_fill_scan_buf(c, (unsigned char *) sm, jeb->offset + c->sector_size -
					sizeof(struct jffs2_sum_marker), sizeof(struct jffs2_sum_marker));
		if (err) {
			kfree(sm);
			return err;
		}

		if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC ) {
			err = jffs2_sum_scan_sumnode(c, jeb, je32_to_cpu(sm->offset), &pseudo_random);
			if (err) {
				kfree(sm);
				return err;
			}
		}

		kfree(sm);

		ofs = jeb->offset;
		prevofs = jeb->offset - 1;
	}

	buf_ofs = jeb->offset;

	if (!buf_size) {
		buf_len = c->sector_size;

		if (jffs2_sum_active()) {
			/* must reread because of summary test */
			err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
			if (err)
				return err;
		}

	} else {
		buf_len = EMPTY_SCAN_SIZE(c->sector_size);
		err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
		if (err)
			return err;
	}

	/* We temporarily use 'ofs' as a pointer into the buffer/jeb */
	ofs = 0;

	/* Scan only 4KiB of 0xFF before declaring it's empty */
	while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
		ofs += 4;

	if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) {
#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
		if (jffs2_cleanmarker_oob(c)) {
			/* scan oob, take care of cleanmarker */
			int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound);
			D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret));
			switch (ret) {
			case 0:		return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF;
			case 1: 	return BLK_STATE_ALLDIRTY;
			default: 	return ret;
			}
		}
#endif
		D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
		if (c->cleanmarker_size == 0)
			return BLK_STATE_CLEANMARKER;	/* don't bother with re-erase */
		else
			return BLK_STATE_ALLFF;	/* OK to erase if all blocks are like this */
	}
	if (ofs) {
		D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset,
			  jeb->offset + ofs));
		DIRTY_SPACE(ofs);
	}

	/* Now ofs is a complete physical flash offset as it always was... */
	ofs += jeb->offset;

	noise = 10;

	dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset);

scan_more:
	while(ofs < jeb->offset + c->sector_size) {

		jffs2_dbg_acct_paranoia_check_nolock(c, jeb);

		cond_resched();

		if (ofs & 3) {
			printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
			ofs = PAD(ofs);
			continue;
		}
		if (ofs == prevofs) {
			printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		prevofs = ofs;

		if (jeb->offset + c->sector_size < ofs + sizeof(*node)) {
			D1(printk(KERN_DEBUG "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n", sizeof(struct jffs2_unknown_node),
				  jeb->offset, c->sector_size, ofs, sizeof(*node)));
			DIRTY_SPACE((jeb->offset + c->sector_size)-ofs);
			break;
		}

		if (buf_ofs + buf_len < ofs + sizeof(*node)) {
			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
			D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n",
				  sizeof(struct jffs2_unknown_node), buf_len, ofs));
			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
			if (err)
				return err;
			buf_ofs = ofs;
		}

		node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs];

		if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
			uint32_t inbuf_ofs;
			uint32_t empty_start;

			empty_start = ofs;
			ofs += 4;

			D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs));
		more_empty:
			inbuf_ofs = ofs - buf_ofs;
			while (inbuf_ofs < buf_len) {
				if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) {
					printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n",
					       empty_start, ofs);
					DIRTY_SPACE(ofs-empty_start);
					goto scan_more;
				}

				inbuf_ofs+=4;
				ofs += 4;
			}
			/* Ran off end. */
			D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs));

			/* If we're only checking the beginning of a block with a cleanmarker,
			   bail now */
			if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) &&
			    c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_phys) {
				D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size)));
				return BLK_STATE_CLEANMARKER;
			}

			/* See how much more there is to read in this eraseblock... */
			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
			if (!buf_len) {
				/* No more to read. Break out of main loop without marking
				   this range of empty space as dirty (because it's not) */
				D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n",
					  empty_start));
				break;
			}
			D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs));
			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
			if (err)
				return err;
			buf_ofs = ofs;
			goto more_empty;
		}

		if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) {
			printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) {
			D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs));
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) {
			printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
			printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) {
			/* OK. We're out of possibilities. Whinge and move on */
			noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n",
				     JFFS2_MAGIC_BITMASK, ofs,
				     je16_to_cpu(node->magic));
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}
		/* We seem to have a node of sorts. Check the CRC */
		crcnode.magic = node->magic;
		crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE);
		crcnode.totlen = node->totlen;
		hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4);

		if (hdr_crc != je32_to_cpu(node->hdr_crc)) {
			noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n",
				     ofs, je16_to_cpu(node->magic),
				     je16_to_cpu(node->nodetype),
				     je32_to_cpu(node->totlen),
				     je32_to_cpu(node->hdr_crc),
				     hdr_crc);
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}

		if (ofs + je32_to_cpu(node->totlen) >
		    jeb->offset + c->sector_size) {
			/* Eep. Node goes over the end of the erase block. */
			printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
			       ofs, je32_to_cpu(node->totlen));
			printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
			DIRTY_SPACE(4);
			ofs += 4;
			continue;
		}

		if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
			/* Wheee. This is an obsoleted node */
			D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs));
			DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
			ofs += PAD(je32_to_cpu(node->totlen));
			continue;
		}

		switch(je16_to_cpu(node->nodetype)) {
		case JFFS2_NODETYPE_INODE:
			if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  sizeof(struct jffs2_raw_inode), buf_len, ofs));
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s);
			if (err) return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		case JFFS2_NODETYPE_DIRENT:
			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
				D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n",
					  je32_to_cpu(node->totlen), buf_len, ofs));
				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
				if (err)
					return err;
				buf_ofs = ofs;
				node = (void *)buf;
			}
			err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s);
			if (err) return err;
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		case JFFS2_NODETYPE_CLEANMARKER:
			D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs));
			if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {
				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n",
				       ofs, je32_to_cpu(node->totlen), c->cleanmarker_size);
				DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
				ofs += PAD(sizeof(struct jffs2_unknown_node));
			} else if (jeb->first_node) {
				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
				DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
				ofs += PAD(sizeof(struct jffs2_unknown_node));
			} else {
				struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref();
				if (!marker_ref) {
					printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n");
					return -ENOMEM;
				}
				marker_ref->next_in_ino = NULL;
				marker_ref->next_phys = NULL;
				marker_ref->flash_offset = ofs | REF_NORMAL;
				marker_ref->__totlen = c->cleanmarker_size;
				jeb->first_node = jeb->last_node = marker_ref;

				USED_SPACE(PAD(c->cleanmarker_size));
				ofs += PAD(c->cleanmarker_size);
			}
			break;

		case JFFS2_NODETYPE_PADDING:
			if (jffs2_sum_active())
				jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen));
			DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
			ofs += PAD(je32_to_cpu(node->totlen));
			break;

		default:
			switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) {
			case JFFS2_FEATURE_ROCOMPAT:
				printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
			        c->flags |= JFFS2_SB_FLAG_RO;
				if (!(jffs2_is_readonly(c)))
					return -EROFS;
				DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
				ofs += PAD(je32_to_cpu(node->totlen));
				break;

			case JFFS2_FEATURE_INCOMPAT:
				printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
				return -EINVAL;

			case JFFS2_FEATURE_RWCOMPAT_DELETE:
				D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
				DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
				ofs += PAD(je32_to_cpu(node->totlen));
				break;

			case JFFS2_FEATURE_RWCOMPAT_COPY:
				D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
				USED_SPACE(PAD(je32_to_cpu(node->totlen)));
				ofs += PAD(je32_to_cpu(node->totlen));
				break;
			}
		}
	}

	if (jffs2_sum_active()) {
		if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) {
			dbg_summary("There is not enough space for "
				"summary information, disabling for this jeb!\n");
			jffs2_sum_disable_collecting(s);
		}
	}

	D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset,
		  jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size));

	/* mark_node_obsolete can add to wasted !! */
	if (jeb->wasted_size) {
		jeb->dirty_size += jeb->wasted_size;
		c->dirty_size += jeb->wasted_size;
		c->wasted_size -= jeb->wasted_size;
		jeb->wasted_size = 0;
	}

	return jffs2_scan_classify_jeb(c, jeb);
}