[JFFS2] Prevent ino cache removal for inodes in use

Don't remove inocache for inodes which are in read_inode() or
clear_inode() until they're done.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

fs/jffs2/erase.c

@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: erase.c,v 1.71 2005/02/09 09:17:40 pavlov Exp $
+ * $Id: erase.c,v 1.72 2005/02/27 23:01:32 dwmw2 Exp $
  *
  */
 
@@ -277,11 +277,8 @@ static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c,
 		printk("\n");
 	});
 
-	if (ic->nodes == (void *)ic) {
-		D1(printk(KERN_DEBUG "inocache for ino #%u is all gone now. Freeing\n", ic->ino));
+	if (ic->nodes == (void *)ic)
 		jffs2_del_ino_cache(c, ic);
-		jffs2_free_inode_cache(ic);
-	}
 }
 
 static void jffs2_free_all_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)

fs/jffs2/nodelist.c

@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: nodelist.c,v 1.92 2005/01/19 19:22:00 tpoynor Exp $
+ * $Id: nodelist.c,v 1.93 2005/02/27 23:01:32 dwmw2 Exp $
  *
  */
 
@@ -506,7 +506,7 @@ void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new
 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
 {
 	struct jffs2_inode_cache **prev;
-	D2(printk(KERN_DEBUG "jffs2_del_ino_cache: Del %p (ino #%u)\n", old, old->ino));
+	D1(printk(KERN_DEBUG "jffs2_del_ino_cache: Del %p (ino #%u)\n", old, old->ino));
 	spin_lock(&c->inocache_lock);
 	
 	prev = &c->inocache_list[old->ino % INOCACHE_HASHSIZE];
@@ -518,6 +518,14 @@ void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
 		*prev = old->next;
 	}
 
+	/* Free it now unless it's in READING or CLEARING state, which
+	   are the transitions upon read_inode() and clear_inode(). The
+	   rest of the time we know nobody else is looking at it, and 
+	   if it's held by read_inode() or clear_inode() they'll free it
+	   for themselves. */
+	if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING)
+		jffs2_free_inode_cache(old);
+
 	spin_unlock(&c->inocache_lock);
 }
 
@@ -530,7 +538,6 @@ void jffs2_free_ino_caches(struct jffs2_sb_info *c)
 		this = c->inocache_list[i];
 		while (this) {
 			next = this->next;
-			D2(printk(KERN_DEBUG "jffs2_free_ino_caches: Freeing ino #%u at %p\n", this->ino, this));
 			jffs2_free_inode_cache(this);
 			this = next;
 		}

fs/jffs2/nodelist.h

@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: nodelist.h,v 1.127 2005/02/09 09:23:53 pavlov Exp $
+ * $Id: nodelist.h,v 1.128 2005/02/27 23:01:32 dwmw2 Exp $
  *
  */
 
@@ -135,6 +135,7 @@ struct jffs2_inode_cache {
 #define INO_STATE_CHECKEDABSENT	3	/* Checked, cleared again */
 #define INO_STATE_GC		4	/* GCing a 'pristine' node */
 #define INO_STATE_READING	5	/* In read_inode() */
+#define INO_STATE_CLEARING	6	/* In clear_inode() */
 
 #define INOCACHE_HASHSIZE 128
 

fs/jffs2/nodemgmt.c

@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: nodemgmt.c,v 1.117 2005/01/25 20:11:11 hammache Exp $
+ * $Id: nodemgmt.c,v 1.118 2005/02/27 23:01:32 dwmw2 Exp $
  *
  */
 
@@ -593,11 +593,8 @@ void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref
 		*p = ref->next_in_ino;
 		ref->next_in_ino = NULL;
 
-		if (ic->nodes == (void *)ic) {
-			D1(printk(KERN_DEBUG "inocache for ino #%u is all gone now. Freeing\n", ic->ino));
+		if (ic->nodes == (void *)ic)
 			jffs2_del_ino_cache(c, ic);
-			jffs2_free_inode_cache(ic);
-		}
 
 		spin_unlock(&c->erase_completion_lock);
 	}

fs/jffs2/readinode.c

@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: readinode.c,v 1.117 2004/11/20 18:06:54 dwmw2 Exp $
+ * $Id: readinode.c,v 1.118 2005/02/27 23:01:33 dwmw2 Exp $
  *
  */
 
@@ -672,6 +672,9 @@ void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f)
 	down(&f->sem);
 	deleted = f->inocache && !f->inocache->nlink;
 
+	if (f->inocache && f->inocache->state != INO_STATE_CHECKING)
+		jffs2_set_inocache_state(c, f->inocache, INO_STATE_CLEARING);
+
 	if (f->metadata) {
 		if (deleted)
 			jffs2_mark_node_obsolete(c, f->metadata->raw);
@@ -688,8 +691,11 @@ void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f)
 		jffs2_free_full_dirent(fd);
 	}
 
-	if (f->inocache && f->inocache->state != INO_STATE_CHECKING)
+	if (f->inocache && f->inocache->state != INO_STATE_CHECKING) {
 		jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT);
+		if (f->inocache->nodes == (void *)f->inocache)
+			jffs2_del_ino_cache(c, f->inocache);
+	}
 
 	up(&f->sem);
 }