1 files changed, 486 insertions, 0 deletions

diff --git a/fs/jffs2/erase.c b/fs/jffs2/erase.c
new file mode 100644
index 0000000000..acd32f05b5
--- /dev/null
+++ b/fs/jffs2/erase.c
@@ -0,0 +1,486 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright © 2001-2007 Red Hat, Inc.
+ * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
+ *
+ * Created by David Woodhouse <dwmw2@infradead.org>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/mtd/mtd.h>
+#include <linux/compiler.h>
+#include <linux/crc32.h>
+#include <linux/sched.h>
+#include <linux/pagemap.h>
+#include "nodelist.h"
+
+static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset);
+static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
+static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
+
+static void jffs2_erase_block(struct jffs2_sb_info *c,
+			      struct jffs2_eraseblock *jeb)
+{
+	int ret;
+	uint32_t bad_offset;
+#ifdef __ECOS
+       ret = jffs2_flash_erase(c, jeb);
+       if (!ret) {
+	       jffs2_erase_succeeded(c, jeb);
+	       return;
+       }
+       bad_offset = jeb->offset;
+#else /* Linux */
+	struct erase_info *instr;
+
+	jffs2_dbg(1, "%s(): erase block %#08x (range %#08x-%#08x)\n",
+		  __func__,
+		  jeb->offset, jeb->offset, jeb->offset + c->sector_size);
+	instr = kzalloc(sizeof(struct erase_info), GFP_KERNEL);
+	if (!instr) {
+		pr_warn("kzalloc for struct erase_info in jffs2_erase_block failed. Refiling block for later\n");
+		mutex_lock(&c->erase_free_sem);
+		spin_lock(&c->erase_completion_lock);
+		list_move(&jeb->list, &c->erase_pending_list);
+		c->erasing_size -= c->sector_size;
+		c->dirty_size += c->sector_size;
+		jeb->dirty_size = c->sector_size;
+		spin_unlock(&c->erase_completion_lock);
+		mutex_unlock(&c->erase_free_sem);
+		return;
+	}
+
+	instr->addr = jeb->offset;
+	instr->len = c->sector_size;
+
+	ret = mtd_erase(c->mtd, instr);
+	if (!ret) {
+		jffs2_erase_succeeded(c, jeb);
+		kfree(instr);
+		return;
+	}
+
+	bad_offset = instr->fail_addr;
+	kfree(instr);
+#endif /* __ECOS */
+
+	if (ret == -ENOMEM || ret == -EAGAIN) {
+		/* Erase failed immediately. Refile it on the list */
+		jffs2_dbg(1, "Erase at 0x%08x failed: %d. Refiling on erase_pending_list\n",
+			  jeb->offset, ret);
+		mutex_lock(&c->erase_free_sem);
+		spin_lock(&c->erase_completion_lock);
+		list_move(&jeb->list, &c->erase_pending_list);
+		c->erasing_size -= c->sector_size;
+		c->dirty_size += c->sector_size;
+		jeb->dirty_size = c->sector_size;
+		spin_unlock(&c->erase_completion_lock);
+		mutex_unlock(&c->erase_free_sem);
+		return;
+	}
+
+	if (ret == -EROFS)
+		pr_warn("Erase at 0x%08x failed immediately: -EROFS. Is the sector locked?\n",
+			jeb->offset);
+	else
+		pr_warn("Erase at 0x%08x failed immediately: errno %d\n",
+			jeb->offset, ret);
+
+	jffs2_erase_failed(c, jeb, bad_offset);
+}
+
+int jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count)
+{
+	struct jffs2_eraseblock *jeb;
+	int work_done = 0;
+
+	mutex_lock(&c->erase_free_sem);
+
+	spin_lock(&c->erase_completion_lock);
+
+	while (!list_empty(&c->erase_complete_list) ||
+	       !list_empty(&c->erase_pending_list)) {
+
+		if (!list_empty(&c->erase_complete_list)) {
+			jeb = list_entry(c->erase_complete_list.next, struct jffs2_eraseblock, list);
+			list_move(&jeb->list, &c->erase_checking_list);
+			spin_unlock(&c->erase_completion_lock);
+			mutex_unlock(&c->erase_free_sem);
+			jffs2_mark_erased_block(c, jeb);
+
+			work_done++;
+			if (!--count) {
+				jffs2_dbg(1, "Count reached. jffs2_erase_pending_blocks leaving\n");
+				goto done;
+			}
+
+		} else if (!list_empty(&c->erase_pending_list)) {
+			jeb = list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list);
+			jffs2_dbg(1, "Starting erase of pending block 0x%08x\n",
+				  jeb->offset);
+			list_del(&jeb->list);
+			c->erasing_size += c->sector_size;
+			c->wasted_size -= jeb->wasted_size;
+			c->free_size -= jeb->free_size;
+			c->used_size -= jeb->used_size;
+			c->dirty_size -= jeb->dirty_size;
+			jeb->wasted_size = jeb->used_size = jeb->dirty_size = jeb->free_size = 0;
+			jffs2_free_jeb_node_refs(c, jeb);
+			list_add(&jeb->list, &c->erasing_list);
+			spin_unlock(&c->erase_completion_lock);
+			mutex_unlock(&c->erase_free_sem);
+
+			jffs2_erase_block(c, jeb);
+
+		} else {
+			BUG();
+		}
+
+		/* Be nice */
+		cond_resched();
+		mutex_lock(&c->erase_free_sem);
+		spin_lock(&c->erase_completion_lock);
+	}
+
+	spin_unlock(&c->erase_completion_lock);
+	mutex_unlock(&c->erase_free_sem);
+ done:
+	jffs2_dbg(1, "jffs2_erase_pending_blocks completed\n");
+	return work_done;
+}
+
+static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
+{
+	jffs2_dbg(1, "Erase completed successfully at 0x%08x\n", jeb->offset);
+	mutex_lock(&c->erase_free_sem);
+	spin_lock(&c->erase_completion_lock);
+	list_move_tail(&jeb->list, &c->erase_complete_list);
+	/* Wake the GC thread to mark them clean */
+	jffs2_garbage_collect_trigger(c);
+	spin_unlock(&c->erase_completion_lock);
+	mutex_unlock(&c->erase_free_sem);
+	wake_up(&c->erase_wait);
+}
+
+static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset)
+{
+	/* For NAND, if the failure did not occur at the device level for a
+	   specific physical page, don't bother updating the bad block table. */
+	if (jffs2_cleanmarker_oob(c) && (bad_offset != (uint32_t)MTD_FAIL_ADDR_UNKNOWN)) {
+		/* We had a device-level failure to erase.  Let's see if we've
+		   failed too many times. */
+		if (!jffs2_write_nand_badblock(c, jeb, bad_offset)) {
+			/* We'd like to give this block another try. */
+			mutex_lock(&c->erase_free_sem);
+			spin_lock(&c->erase_completion_lock);
+			list_move(&jeb->list, &c->erase_pending_list);
+			c->erasing_size -= c->sector_size;
+			c->dirty_size += c->sector_size;
+			jeb->dirty_size = c->sector_size;
+			spin_unlock(&c->erase_completion_lock);
+			mutex_unlock(&c->erase_free_sem);
+			return;
+		}
+	}
+
+	mutex_lock(&c->erase_free_sem);
+	spin_lock(&c->erase_completion_lock);
+	c->erasing_size -= c->sector_size;
+	c->bad_size += c->sector_size;
+	list_move(&jeb->list, &c->bad_list);
+	c->nr_erasing_blocks--;
+	spin_unlock(&c->erase_completion_lock);
+	mutex_unlock(&c->erase_free_sem);
+	wake_up(&c->erase_wait);
+}
+
+/* Hmmm. Maybe we should accept the extra space it takes and make
+   this a standard doubly-linked list? */
+static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c,
+			struct jffs2_raw_node_ref *ref, struct jffs2_eraseblock *jeb)
+{
+	struct jffs2_inode_cache *ic = NULL;
+	struct jffs2_raw_node_ref **prev;
+
+	prev = &ref->next_in_ino;
+
+	/* Walk the inode's list once, removing any nodes from this eraseblock */
+	while (1) {
+		if (!(*prev)->next_in_ino) {
+			/* We're looking at the jffs2_inode_cache, which is
+			   at the end of the linked list. Stash it and continue
+			   from the beginning of the list */
+			ic = (struct jffs2_inode_cache *)(*prev);
+			prev = &ic->nodes;
+			continue;
+		}
+
+		if (SECTOR_ADDR((*prev)->flash_offset) == jeb->offset) {
+			/* It's in the block we're erasing */
+			struct jffs2_raw_node_ref *this;
+
+			this = *prev;
+			*prev = this->next_in_ino;
+			this->next_in_ino = NULL;
+
+			if (this == ref)
+				break;
+
+			continue;
+		}
+		/* Not to be deleted. Skip */
+		prev = &((*prev)->next_in_ino);
+	}
+
+	/* PARANOIA */
+	if (!ic) {
+		JFFS2_WARNING("inode_cache/xattr_datum/xattr_ref"
+			      " not found in remove_node_refs()!!\n");
+		return;
+	}
+
+	jffs2_dbg(1, "Removed nodes in range 0x%08x-0x%08x from ino #%u\n",
+		  jeb->offset, jeb->offset + c->sector_size, ic->ino);
+
+	D2({
+		int i=0;
+		struct jffs2_raw_node_ref *this;
+		printk(KERN_DEBUG "After remove_node_refs_from_ino_list: \n");
+
+		this = ic->nodes;
+
+		printk(KERN_DEBUG);
+		while(this) {
+			pr_cont("0x%08x(%d)->",
+			       ref_offset(this), ref_flags(this));
+			if (++i == 5) {
+				printk(KERN_DEBUG);
+				i=0;
+			}
+			this = this->next_in_ino;
+		}
+		pr_cont("\n");
+	});
+
+	switch (ic->class) {
+#ifdef CONFIG_JFFS2_FS_XATTR
+		case RAWNODE_CLASS_XATTR_DATUM:
+			jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic);
+			break;
+		case RAWNODE_CLASS_XATTR_REF:
+			jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic);
+			break;
+#endif
+		default:
+			if (ic->nodes == (void *)ic && ic->pino_nlink == 0)
+				jffs2_del_ino_cache(c, ic);
+	}
+}
+
+void jffs2_free_jeb_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
+{
+	struct jffs2_raw_node_ref *block, *ref;
+	jffs2_dbg(1, "Freeing all node refs for eraseblock offset 0x%08x\n",
+		  jeb->offset);
+
+	block = ref = jeb->first_node;
+
+	while (ref) {
+		if (ref->flash_offset == REF_LINK_NODE) {
+			ref = ref->next_in_ino;
+			jffs2_free_refblock(block);
+			block = ref;
+			continue;
+		}
+		if (ref->flash_offset != REF_EMPTY_NODE && ref->next_in_ino)
+			jffs2_remove_node_refs_from_ino_list(c, ref, jeb);
+		/* else it was a non-inode node or already removed, so don't bother */
+
+		ref++;
+	}
+	jeb->first_node = jeb->last_node = NULL;
+}
+
+static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t *bad_offset)
+{
+	void *ebuf;
+	uint32_t ofs;
+	size_t retlen;
+	int ret;
+	unsigned long *wordebuf;
+
+	ret = mtd_point(c->mtd, jeb->offset, c->sector_size, &retlen,
+			&ebuf, NULL);
+	if (ret != -EOPNOTSUPP) {
+		if (ret) {
+			jffs2_dbg(1, "MTD point failed %d\n", ret);
+			goto do_flash_read;
+		}
+		if (retlen < c->sector_size) {
+			/* Don't muck about if it won't let us point to the whole erase sector */
+			jffs2_dbg(1, "MTD point returned len too short: 0x%zx\n",
+				  retlen);
+			mtd_unpoint(c->mtd, jeb->offset, retlen);
+			goto do_flash_read;
+		}
+		wordebuf = ebuf-sizeof(*wordebuf);
+		retlen /= sizeof(*wordebuf);
+		do {
+		   if (*++wordebuf != ~0)
+			   break;
+		} while(--retlen);
+		mtd_unpoint(c->mtd, jeb->offset, c->sector_size);
+		if (retlen) {
+			pr_warn("Newly-erased block contained word 0x%lx at offset 0x%08tx\n",
+				*wordebuf,
+				jeb->offset +
+				c->sector_size-retlen * sizeof(*wordebuf));
+			return -EIO;
+		}
+		return 0;
+	}
+ do_flash_read:
+	ebuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!ebuf) {
+		pr_warn("Failed to allocate page buffer for verifying erase at 0x%08x. Refiling\n",
+			jeb->offset);
+		return -EAGAIN;
+	}
+
+	jffs2_dbg(1, "Verifying erase at 0x%08x\n", jeb->offset);
+
+	for (ofs = jeb->offset; ofs < jeb->offset + c->sector_size; ) {
+		uint32_t readlen = min((uint32_t)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
+		int i;
+
+		*bad_offset = ofs;
+
+		ret = mtd_read(c->mtd, ofs, readlen, &retlen, ebuf);
+		if (ret) {
+			pr_warn("Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n",
+				ofs, ret);
+			ret = -EIO;
+			goto fail;
+		}
+		if (retlen != readlen) {
+			pr_warn("Short read from newly-erased block at 0x%08x. Wanted %d, got %zd\n",
+				ofs, readlen, retlen);
+			ret = -EIO;
+			goto fail;
+		}
+		for (i=0; i<readlen; i += sizeof(unsigned long)) {
+			/* It's OK. We know it's properly aligned */
+			unsigned long *datum = ebuf + i;
+			if (*datum + 1) {
+				*bad_offset += i;
+				pr_warn("Newly-erased block contained word 0x%lx at offset 0x%08x\n",
+					*datum, *bad_offset);
+				ret = -EIO;
+				goto fail;
+			}
+		}
+		ofs += readlen;
+		cond_resched();
+	}
+	ret = 0;
+fail:
+	kfree(ebuf);
+	return ret;
+}
+
+static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
+{
+	size_t retlen;
+	int ret;
+	uint32_t bad_offset;
+
+	switch (jffs2_block_check_erase(c, jeb, &bad_offset)) {
+	case -EAGAIN:	goto refile;
+	case -EIO:	goto filebad;
+	}
+
+	/* Write the erase complete marker */
+	jffs2_dbg(1, "Writing erased marker to block at 0x%08x\n", jeb->offset);
+	bad_offset = jeb->offset;
+
+	/* Cleanmarker in oob area or no cleanmarker at all ? */
+	if (jffs2_cleanmarker_oob(c) || c->cleanmarker_size == 0) {
+
+		if (jffs2_cleanmarker_oob(c)) {
+			if (jffs2_write_nand_cleanmarker(c, jeb))
+				goto filebad;
+		}
+	} else {
+
+		struct kvec vecs[1];
+		struct jffs2_unknown_node marker = {
+			.magic =	cpu_to_je16(JFFS2_MAGIC_BITMASK),
+			.nodetype =	cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER),
+			.totlen =	cpu_to_je32(c->cleanmarker_size)
+		};
+
+		jffs2_prealloc_raw_node_refs(c, jeb, 1);
+
+		marker.hdr_crc = cpu_to_je32(crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4));
+
+		vecs[0].iov_base = (unsigned char *) &marker;
+		vecs[0].iov_len = sizeof(marker);
+		ret = jffs2_flash_direct_writev(c, vecs, 1, jeb->offset, &retlen);
+
+		if (ret || retlen != sizeof(marker)) {
+			if (ret)
+				pr_warn("Write clean marker to block at 0x%08x failed: %d\n",
+				       jeb->offset, ret);
+			else
+				pr_warn("Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
+				       jeb->offset, sizeof(marker), retlen);
+
+			goto filebad;
+		}
+	}
+	/* Everything else got zeroed before the erase */
+	jeb->free_size = c->sector_size;
+
+	mutex_lock(&c->erase_free_sem);
+	spin_lock(&c->erase_completion_lock);
+
+	c->erasing_size -= c->sector_size;
+	c->free_size += c->sector_size;
+
+	/* Account for cleanmarker now, if it's in-band */
+	if (c->cleanmarker_size && !jffs2_cleanmarker_oob(c))
+		jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
+
+	list_move_tail(&jeb->list, &c->free_list);
+	c->nr_erasing_blocks--;
+	c->nr_free_blocks++;
+
+	jffs2_dbg_acct_sanity_check_nolock(c, jeb);
+	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
+
+	spin_unlock(&c->erase_completion_lock);
+	mutex_unlock(&c->erase_free_sem);
+	wake_up(&c->erase_wait);
+	return;
+
+filebad:
+	jffs2_erase_failed(c, jeb, bad_offset);
+	return;
+
+refile:
+	/* Stick it back on the list from whence it came and come back later */
+	mutex_lock(&c->erase_free_sem);
+	spin_lock(&c->erase_completion_lock);
+	jffs2_garbage_collect_trigger(c);
+	list_move(&jeb->list, &c->erase_complete_list);
+	spin_unlock(&c->erase_completion_lock);
+	mutex_unlock(&c->erase_free_sem);
+	return;
+}