1 files changed, 289 insertions, 188 deletions

diff --git a/linux-2.4.x/fs/jffs2/build.c b/linux-2.4.x/fs/jffs2/build.c
index 57a3c09..e77ddfd 100644
--- a/linux-2.4.x/fs/jffs2/build.c
+++ b/linux-2.4.x/fs/jffs2/build.c
@@ -1,265 +1,366 @@
 /*
  * JFFS2 -- Journalling Flash File System, Version 2.
  *
- * Copyright (C) 2001 Red Hat, Inc.
+ * Copyright (C) 2001-2003 Red Hat, Inc.
  *
- * Created by David Woodhouse <dwmw2@cambridge.redhat.com>
+ * Created by David Woodhouse <dwmw2@infradead.org>
  *
- * The original JFFS, from which the design for JFFS2 was derived,
- * was designed and implemented by Axis Communications AB.
+ * For licensing information, see the file 'LICENCE' in this directory.
  *
- * The contents of this file are subject to the Red Hat eCos Public
- * License Version 1.1 (the "Licence"); you may not use this file
- * except in compliance with the Licence.  You may obtain a copy of
- * the Licence at http://www.redhat.com/
- *
- * Software distributed under the Licence is distributed on an "AS IS"
- * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.
- * See the Licence for the specific language governing rights and
- * limitations under the Licence.
- *
- * The Original Code is JFFS2 - Journalling Flash File System, version 2
- *
- * Alternatively, the contents of this file may be used under the
- * terms of the GNU General Public License version 2 (the "GPL"), in
- * which case the provisions of the GPL are applicable instead of the
- * above.  If you wish to allow the use of your version of this file
- * only under the terms of the GPL and not to allow others to use your
- * version of this file under the RHEPL, indicate your decision by
- * deleting the provisions above and replace them with the notice and
- * other provisions required by the GPL.  If you do not delete the
- * provisions above, a recipient may use your version of this file
- * under either the RHEPL or the GPL.
- *
- * $Id: build.c,v 1.16.2.2 2002/03/12 15:36:43 dwmw2 Exp $
+ * $Id: build.c,v 1.87 2005/11/18 07:27:45 forrest Exp $
  *
  */
 
 #include <linux/kernel.h>
-#include <linux/jffs2.h>
+#include <linux/sched.h>
 #include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mtd/mtd.h>
 #include "nodelist.h"
 
-int jffs2_build_inode_pass1(struct jffs2_sb_info *, struct jffs2_inode_cache *);
-int jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *, struct jffs2_inode_cache *);
+static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *,
+		struct jffs2_inode_cache *, struct jffs2_full_dirent **);
+
+static inline struct jffs2_inode_cache *
+first_inode_chain(int *i, struct jffs2_sb_info *c)
+{
+	for (; *i < INOCACHE_HASHSIZE; (*i)++) {
+		if (c->inocache_list[*i])
+			return c->inocache_list[*i];
+	}
+	return NULL;
+}
+
+static inline struct jffs2_inode_cache *
+next_inode(int *i, struct jffs2_inode_cache *ic, struct jffs2_sb_info *c)
+{
+	/* More in this chain? */
+	if (ic->next)
+		return ic->next;
+	(*i)++;
+	return first_inode_chain(i, c);
+}
+
+#define for_each_inode(i, c, ic)			\
+	for (i = 0, ic = first_inode_chain(&i, (c));	\
+	     ic;					\
+	     ic = next_inode(&i, ic, (c)))
+
+
+static inline void jffs2_build_inode_pass1(struct jffs2_sb_info *c,
+					struct jffs2_inode_cache *ic)
+{
+	struct jffs2_full_dirent *fd;
+
+	dbg_fsbuild("building directory inode #%u\n", ic->ino);
+
+	/* For each child, increase nlink */
+	for(fd = ic->scan_dents; fd; fd = fd->next) {
+		struct jffs2_inode_cache *child_ic;
+		if (!fd->ino)
+			continue;
+
+		/* we can get high latency here with huge directories */
 
+		child_ic = jffs2_get_ino_cache(c, fd->ino);
+		if (!child_ic) {
+			dbg_fsbuild("child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n",
+				  fd->name, fd->ino, ic->ino);
+			jffs2_mark_node_obsolete(c, fd->raw);
+			continue;
+		}
 
-#define for_each_inode(i, c, ic) for (i=0; i<INOCACHE_HASHSIZE; i++) for (ic=c->inocache_list[i]; ic; ic=ic->next) 
+		if (child_ic->nlink++ && fd->type == DT_DIR) {
+			JFFS2_ERROR("child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n",
+				fd->name, fd->ino, ic->ino);
+			/* TODO: What do we do about it? */
+		}
+		dbg_fsbuild("increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino);
+		/* Can't free scan_dents so far. We might need them in pass 2 */
+	}
+}
 
 /* Scan plan:
  - Scan physical nodes. Build map of inodes/dirents. Allocate inocaches as we go
  - Scan directory tree from top down, setting nlink in inocaches
  - Scan inocaches for inodes with nlink==0
 */
-int jffs2_build_filesystem(struct jffs2_sb_info *c)
+static int jffs2_build_filesystem(struct jffs2_sb_info *c)
 {
 	int ret;
 	int i;
 	struct jffs2_inode_cache *ic;
+	struct jffs2_full_dirent *fd;
+	struct jffs2_full_dirent *dead_fds = NULL;
+
+	dbg_fsbuild("build FS data structures\n");
 
 	/* First, scan the medium and build all the inode caches with
 	   lists of physical nodes */
 
-	c->flags |= JFFS2_SB_FLAG_MOUNTING;
+	c->flags |= JFFS2_SB_FLAG_SCANNING;
 	ret = jffs2_scan_medium(c);
-	c->flags &= ~JFFS2_SB_FLAG_MOUNTING;
-
+	c->flags &= ~JFFS2_SB_FLAG_SCANNING;
 	if (ret)
-		return ret;
+		goto exit;
+
+	dbg_fsbuild("scanned flash completely\n");
+	jffs2_dbg_dump_block_lists_nolock(c);
 
-	D1(printk(KERN_DEBUG "Scanned flash completely\n"));
-	/* Now build the data map for each inode, marking obsoleted nodes
-	   as such, and also increase nlink of any children. */
+	dbg_fsbuild("pass 1 starting\n");
+	c->flags |= JFFS2_SB_FLAG_BUILDING;
+	/* Now scan the directory tree, increasing nlink according to every dirent found. */
 	for_each_inode(i, c, ic) {
-		D1(printk(KERN_DEBUG "Pass 1: ino #%u\n", ic->ino));
-		ret = jffs2_build_inode_pass1(c, ic);
-		if (ret) {
-			D1(printk(KERN_WARNING "Eep. jffs2_build_inode_pass1 for ino %d returned %d\n", ic->ino, ret));
-			return ret;
+		if (ic->scan_dents) {
+			jffs2_build_inode_pass1(c, ic);
+			cond_resched();
 		}
 	}
-	D1(printk(KERN_DEBUG "Pass 1 complete\n"));
+
+	dbg_fsbuild("pass 1 complete\n");
 
 	/* Next, scan for inodes with nlink == 0 and remove them. If
 	   they were directories, then decrement the nlink of their
 	   children too, and repeat the scan. As that's going to be
 	   a fairly uncommon occurrence, it's not so evil to do it this
 	   way. Recursion bad. */
-	do { 
-		D1(printk(KERN_DEBUG "Pass 2 (re)starting\n"));
-		ret = 0;
-		for_each_inode(i, c, ic) {
-			D1(printk(KERN_DEBUG "Pass 2: ino #%u, nlink %d, ic %p, nodes %p\n", ic->ino, ic->nlink, ic, ic->nodes));
-			if (ic->nlink)
-				continue;
-			
-			ret = jffs2_build_remove_unlinked_inode(c, ic);
-			if (ret)
-				break;
-		/* -EAGAIN means the inode's nlink was zero, so we deleted it,
-		   and furthermore that it had children and their nlink has now
-		   gone to zero too. So we have to restart the scan. */
-		} 
-	} while(ret == -EAGAIN);
-	
-	D1(printk(KERN_DEBUG "Pass 2 complete\n"));
-	
-	/* Finally, we can scan again and free the dirent nodes and scan_info structs */
+	dbg_fsbuild("pass 2 starting\n");
+
 	for_each_inode(i, c, ic) {
-		struct jffs2_scan_info *scan = ic->scan;
-		struct jffs2_full_dirent *fd;
-		D1(printk(KERN_DEBUG "Pass 3: ino #%u, ic %p, nodes %p\n", ic->ino, ic, ic->nodes));
-		if (!scan) {
-			if (ic->nlink) {
-				D1(printk(KERN_WARNING "Why no scan struct for ino #%u which has nlink %d?\n", ic->ino, ic->nlink));
-			}
+		if (ic->nlink)
 			continue;
-		}
-		ic->scan = NULL;
-		while(scan->dents) {
-			fd = scan->dents;
-			scan->dents = fd->next;
-			jffs2_free_full_dirent(fd);
-		}
-		kfree(scan);
+
+		jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
+		cond_resched();
 	}
-	D1(printk(KERN_DEBUG "Pass 3 complete\n"));
 
-	return ret;
-}
-	
-int jffs2_build_inode_pass1(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
-{
-	struct jffs2_tmp_dnode_info *tn;
-	struct jffs2_full_dirent *fd;
-	struct jffs2_node_frag *fraglist = NULL;
-	struct jffs2_tmp_dnode_info *metadata = NULL;
+	dbg_fsbuild("pass 2a starting\n");
 
-	D1(printk(KERN_DEBUG "jffs2_build_inode building inode #%u\n", ic->ino));
-	if (ic->ino > c->highest_ino)
-		c->highest_ino = ic->ino;
+	while (dead_fds) {
+		fd = dead_fds;
+		dead_fds = fd->next;
 
-	if (!ic->scan->tmpnodes && ic->ino != 1) {
-		D1(printk(KERN_DEBUG "jffs2_build_inode: ino #%u has no data nodes!\n", ic->ino));
-	}
-	/* Build the list to make sure any obsolete nodes are marked as such */
-	while(ic->scan->tmpnodes) {
-		tn = ic->scan->tmpnodes;
-		ic->scan->tmpnodes = tn->next;
-		
-		if (metadata && tn->version > metadata->version) {
-			D1(printk(KERN_DEBUG "jffs2_build_inode_pass1 ignoring old metadata at 0x%08x\n",
-				  metadata->fn->raw->flash_offset &~3));
-			
-			jffs2_free_full_dnode(metadata->fn);
-			jffs2_free_tmp_dnode_info(metadata);
-			metadata = NULL;
-		}
-			
-		if (tn->fn->size) {
-			jffs2_add_full_dnode_to_fraglist (c, &fraglist, tn->fn);
-			jffs2_free_tmp_dnode_info(tn);
-		} else {
-			if (!metadata) {
-				metadata = tn;
-			} else {
-				D1(printk(KERN_DEBUG "jffs2_build_inode_pass1 ignoring new metadata at 0x%08x\n",
-					  tn->fn->raw->flash_offset &~3));
-				
-				jffs2_free_full_dnode(tn->fn);
-				jffs2_free_tmp_dnode_info(tn);
-			}
-		}
-	}
-		
-	/* OK. Now clear up */
-	if (metadata) {
-		jffs2_free_full_dnode(metadata->fn);
-		jffs2_free_tmp_dnode_info(metadata);
+		ic = jffs2_get_ino_cache(c, fd->ino);
+
+		if (ic)
+			jffs2_build_remove_unlinked_inode(c, ic, &dead_fds);
+		jffs2_free_full_dirent(fd);
 	}
-	metadata = NULL;
-	
-	while (fraglist) {
-		struct jffs2_node_frag *frag;
-		frag = fraglist;
-		fraglist = fraglist->next;
-		
-		if (frag->node && !(--frag->node->frags)) {
-			jffs2_free_full_dnode(frag->node);
+
+	dbg_fsbuild("pass 2a complete\n");
+	dbg_fsbuild("freeing temporary data structures\n");
+
+	/* Finally, we can scan again and free the dirent structs */
+	for_each_inode(i, c, ic) {
+		while(ic->scan_dents) {
+			fd = ic->scan_dents;
+			ic->scan_dents = fd->next;
+			jffs2_free_full_dirent(fd);
 		}
-		jffs2_free_node_frag(frag);
+		ic->scan_dents = NULL;
+		cond_resched();
 	}
+	c->flags &= ~JFFS2_SB_FLAG_BUILDING;
 
-	/* Now for each child, increase nlink */
-	for(fd=ic->scan->dents; fd; fd = fd->next) {
-		struct jffs2_inode_cache *child_ic;
-		if (!fd->ino)
-			continue;
+	dbg_fsbuild("FS build complete\n");
 
-		child_ic = jffs2_get_ino_cache(c, fd->ino);
-		if (!child_ic) {
-			printk(KERN_NOTICE "Eep. Child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n",
-				  fd->name, fd->ino, ic->ino);
-			continue;
-		}
+	/* Rotate the lists by some number to ensure wear levelling */
+	jffs2_rotate_lists(c);
 
-		if (child_ic->nlink++ && fd->type == DT_DIR) {
-			printk(KERN_NOTICE "Child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n", fd->name, fd->ino, ic->ino);
-			if (fd->ino == 1 && ic->ino == 1) {
-				printk(KERN_NOTICE "This is mostly harmless, and probably caused by creating a JFFS2 image\n");
-				printk(KERN_NOTICE "using a buggy version of mkfs.jffs2. Use at least v1.17.\n");
+	ret = 0;
+
+exit:
+	if (ret) {
+		for_each_inode(i, c, ic) {
+			while(ic->scan_dents) {
+				fd = ic->scan_dents;
+				ic->scan_dents = fd->next;
+				jffs2_free_full_dirent(fd);
 			}
-			/* What do we do about it? */
 		}
-		D1(printk(KERN_DEBUG "Increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino));
-		/* Can't free them. We might need them in pass 2 */
 	}
-	return 0;
+
+	return ret;
 }
 
-int jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
+static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c,
+					struct jffs2_inode_cache *ic,
+					struct jffs2_full_dirent **dead_fds)
 {
 	struct jffs2_raw_node_ref *raw;
 	struct jffs2_full_dirent *fd;
-	int ret = 0;
 
-	if(!ic->scan) {
-		D1(printk(KERN_DEBUG "ino #%u was already removed\n", ic->ino));
-		return 0;
-	}
+	dbg_fsbuild("removing ino #%u with nlink == zero.\n", ic->ino);
 
-	D1(printk(KERN_DEBUG "JFFS2: Removing ino #%u with nlink == zero.\n", ic->ino));
-	
-	for (raw = ic->nodes; raw != (void *)ic; raw = raw->next_in_ino) {
-		D1(printk(KERN_DEBUG "obsoleting node at 0x%08x\n", raw->flash_offset&~3));
+	raw = ic->nodes;
+	while (raw != (void *)ic) {
+		struct jffs2_raw_node_ref *next = raw->next_in_ino;
+		dbg_fsbuild("obsoleting node at 0x%08x\n", ref_offset(raw));
 		jffs2_mark_node_obsolete(c, raw);
+		raw = next;
 	}
 
-	if (ic->scan->dents) {
-		printk(KERN_NOTICE "Inode #%u was a directory with children - removing those too...\n", ic->ino);
-	
-		while(ic->scan->dents) {
+	if (ic->scan_dents) {
+		int whinged = 0;
+		dbg_fsbuild("inode #%u was a directory which may have children...\n", ic->ino);
+
+		while(ic->scan_dents) {
 			struct jffs2_inode_cache *child_ic;
 
-			fd = ic->scan->dents;
-			ic->scan->dents = fd->next;
+			fd = ic->scan_dents;
+			ic->scan_dents = fd->next;
+
+			if (!fd->ino) {
+				/* It's a deletion dirent. Ignore it */
+				dbg_fsbuild("child \"%s\" is a deletion dirent, skipping...\n", fd->name);
+				jffs2_free_full_dirent(fd);
+				continue;
+			}
+			if (!whinged)
+				whinged = 1;
+
+			dbg_fsbuild("removing child \"%s\", ino #%u\n", fd->name, fd->ino);
 
-			D1(printk(KERN_DEBUG "Removing child \"%s\", ino #%u\n",
-				  fd->name, fd->ino));
-			
 			child_ic = jffs2_get_ino_cache(c, fd->ino);
 			if (!child_ic) {
-				printk(KERN_NOTICE "Cannot remove child \"%s\", ino #%u, because it doesn't exist\n", fd->name, fd->ino);
+				dbg_fsbuild("cannot remove child \"%s\", ino #%u, because it doesn't exist\n",
+						fd->name, fd->ino);
+				jffs2_free_full_dirent(fd);
 				continue;
 			}
-			jffs2_free_full_dirent(fd);
+
+			/* Reduce nlink of the child. If it's now zero, stick it on the
+			   dead_fds list to be cleaned up later. Else just free the fd */
+
 			child_ic->nlink--;
+
+			if (!child_ic->nlink) {
+				dbg_fsbuild("inode #%u (\"%s\") has now got zero nlink, adding to dead_fds list.\n",
+					  fd->ino, fd->name);
+				fd->next = *dead_fds;
+				*dead_fds = fd;
+			} else {
+				dbg_fsbuild("inode #%u (\"%s\") has now got nlink %d. Ignoring.\n",
+					  fd->ino, fd->name, child_ic->nlink);
+				jffs2_free_full_dirent(fd);
+			}
 		}
-		ret = -EAGAIN;
 	}
-	kfree(ic->scan);
-	ic->scan = NULL;
-	//	jffs2_del_ino_cache(c, ic);
-	//	jffs2_free_inode_cache(ic);
-	return ret;
+
+	/*
+	   We don't delete the inocache from the hash list and free it yet.
+	   The erase code will do that, when all the nodes are completely gone.
+	*/
+}
+
+static void jffs2_calc_trigger_levels(struct jffs2_sb_info *c)
+{
+	uint32_t size;
+
+	/* Deletion should almost _always_ be allowed. We're fairly
+	   buggered once we stop allowing people to delete stuff
+	   because there's not enough free space... */
+	c->resv_blocks_deletion = 2;
+
+	/* Be conservative about how much space we need before we allow writes.
+	   On top of that which is required for deletia, require an extra 2%
+	   of the medium to be available, for overhead caused by nodes being
+	   split across blocks, etc. */
+
+	size = c->flash_size / 50; /* 2% of flash size */
+	size += c->nr_blocks * 100; /* And 100 bytes per eraseblock */
+	size += c->sector_size - 1; /* ... and round up */
+
+	c->resv_blocks_write = c->resv_blocks_deletion + (size / c->sector_size);
+
+	/* When do we let the GC thread run in the background */
+
+	c->resv_blocks_gctrigger = c->resv_blocks_write + 1;
+
+	/* When do we allow garbage collection to merge nodes to make
+	   long-term progress at the expense of short-term space exhaustion? */
+	c->resv_blocks_gcmerge = c->resv_blocks_deletion + 1;
+
+	/* When do we allow garbage collection to eat from bad blocks rather
+	   than actually making progress? */
+	c->resv_blocks_gcbad = 0;//c->resv_blocks_deletion + 2;
+
+	/* If there's less than this amount of dirty space, don't bother
+	   trying to GC to make more space. It'll be a fruitless task */
+	c->nospc_dirty_size = c->sector_size + (c->flash_size / 100);
+
+	dbg_fsbuild("JFFS2 trigger levels (size %d KiB, block size %d KiB, %d blocks)\n",
+		  c->flash_size / 1024, c->sector_size / 1024, c->nr_blocks);
+	dbg_fsbuild("Blocks required to allow deletion:    %d (%d KiB)\n",
+		  c->resv_blocks_deletion, c->resv_blocks_deletion*c->sector_size/1024);
+	dbg_fsbuild("Blocks required to allow writes:      %d (%d KiB)\n",
+		  c->resv_blocks_write, c->resv_blocks_write*c->sector_size/1024);
+	dbg_fsbuild("Blocks required to quiesce GC thread: %d (%d KiB)\n",
+		  c->resv_blocks_gctrigger, c->resv_blocks_gctrigger*c->sector_size/1024);
+	dbg_fsbuild("Blocks required to allow GC merges:   %d (%d KiB)\n",
+		  c->resv_blocks_gcmerge, c->resv_blocks_gcmerge*c->sector_size/1024);
+	dbg_fsbuild("Blocks required to GC bad blocks:     %d (%d KiB)\n",
+		  c->resv_blocks_gcbad, c->resv_blocks_gcbad*c->sector_size/1024);
+	dbg_fsbuild("Amount of dirty space required to GC: %d bytes\n",
+		  c->nospc_dirty_size);
+}
+
+static void jffs2_init_hash_tables(struct jffs2_sb_info *c)
+{
+	int i;
+
+	for (i=0; i<HASH_SIZE; i++) {
+		INIT_LIST_HEAD(&(c->used_blocks[i].chain));
+		INIT_LIST_HEAD(&(c->free_blocks[i].chain));
+	}
+	c->used_blocks_current_index = HASH_SIZE;
+	c->free_blocks_current_index = HASH_SIZE;
+	return;
+}
+
+int jffs2_do_mount_fs(struct jffs2_sb_info *c)
+{
+	int ret;
+
+	c->free_size = c->flash_size;
+	c->nr_blocks = c->flash_size / c->sector_size;
+
+	ret = jffs2_alloc_eraseblocks(c);
+	if (ret)
+		return ret;
+
+	INIT_LIST_HEAD(&c->clean_list);
+	INIT_LIST_HEAD(&c->very_dirty_list);
+	INIT_LIST_HEAD(&c->dirty_list);
+	INIT_LIST_HEAD(&c->erasable_list);
+	INIT_LIST_HEAD(&c->erasing_list);
+	INIT_LIST_HEAD(&c->erase_pending_list);
+	INIT_LIST_HEAD(&c->erasable_pending_wbuf_list);
+	INIT_LIST_HEAD(&c->erase_complete_list);
+	INIT_LIST_HEAD(&c->free_list);
+	INIT_LIST_HEAD(&c->bad_list);
+	INIT_LIST_HEAD(&c->bad_used_list);
+	c->highest_ino = 1;
+	c->summary = NULL;
+
+	jffs2_init_hash_tables(c);
+
+	ret = jffs2_sum_init(c);
+	if (ret) {
+		jffs2_free_eraseblocks(c);
+		return ret;
+
+	}
+
+	if (jffs2_build_filesystem(c)) {
+		dbg_fsbuild("build_fs failed\n");
+		jffs2_free_ino_caches(c);
+		jffs2_free_raw_node_refs(c);
+		jffs2_free_eraseblocks(c);
+		return -EIO;
+	}
+
+	jffs2_calc_trigger_levels(c);
+
+	return 0;
 }