--- 2.2.12-final/fs/buffer.c	Tue Aug 17 22:42:50 1999
+++ /tmp/buffer.c	Wed Aug 18 11:29:56 1999
@@ -395,31 +395,6 @@
 	return err;
 }
 
-void invalidate_buffers(kdev_t dev)
-{
-	int i;
-	int nlist;
-	struct buffer_head * bh;
-
-	for(nlist = 0; nlist < NR_LIST; nlist++) {
-		bh = lru_list[nlist];
-		for (i = nr_buffers_type[nlist]*2 ; --i > 0 ; bh = bh->b_next_free) {
-			if (bh->b_dev != dev)
-				continue;
-			wait_on_buffer(bh);
-			if (bh->b_dev != dev)
-				continue;
-			if (bh->b_count)
-				continue;
-			bh->b_flushtime = 0;
-			clear_bit(BH_Protected, &bh->b_state);
-			clear_bit(BH_Uptodate, &bh->b_state);
-			clear_bit(BH_Dirty, &bh->b_state);
-			clear_bit(BH_Req, &bh->b_state);
-		}
-	}
-}
-
 #define _hashfn(dev,block) (((unsigned)(HASHDEV(dev)^block)) & bh_hash_mask)
 #define hash(dev,block) hash_table[_hashfn(dev,block)]
 
@@ -486,11 +461,14 @@
 	remove_from_lru_list(bh);
 }
 
-static inline void put_last_free(struct buffer_head * bh)
+static void put_last_free(struct buffer_head * bh)
 {
 	if (bh) {
 		struct buffer_head **bhp = &free_list[BUFSIZE_INDEX(bh->b_size)];
 
+		bh->b_count = 0;
+		bh->b_state = 0;
+		remove_from_queues(bh);
 		bh->b_dev = B_FREE;  /* So it is obvious we are on the free list. */
 
 		/* Add to back of free list. */
@@ -510,7 +488,7 @@
 {
 	/* put at end of free list */
 	if(bh->b_dev == B_FREE) {
-		put_last_free(bh);
+		panic("B_FREE inserted into queues");
 	} else {
 		struct buffer_head **bhp = &lru_list[bh->b_list];
 
@@ -600,64 +578,46 @@
 	return 0;
 }
 
-#if 0
-void set_blocksize(kdev_t dev, int size)
+void invalidate_buffers(kdev_t dev)
 {
-	extern int *blksize_size[];
-	int i, nlist;
-	struct buffer_head * bh, *bhnext;
-
-	if (!blksize_size[MAJOR(dev)])
-		return;
+	int i, nlist, slept;
+	struct buffer_head * bh, * bhnext;
 
-	/* Size must be a power of two, and between 512 and PAGE_SIZE */
-	if (size > PAGE_SIZE || size < 512 || (size & (size-1)))
-		panic("Invalid blocksize passed to set_blocksize");
-
-	if (blksize_size[MAJOR(dev)][MINOR(dev)] == 0 && size == BLOCK_SIZE) {
-		blksize_size[MAJOR(dev)][MINOR(dev)] = size;
-		return;
-	}
-	if (blksize_size[MAJOR(dev)][MINOR(dev)] == size)
-		return;
-	sync_buffers(dev, 2);
-	blksize_size[MAJOR(dev)][MINOR(dev)] = size;
-
-	/* We need to be quite careful how we do this - we are moving entries
-	 * around on the free list, and we can get in a loop if we are not careful.
-	 */
+ again:
+	slept = 0;
 	for(nlist = 0; nlist < NR_LIST; nlist++) {
 		bh = lru_list[nlist];
-		for (i = nr_buffers_type[nlist]*2 ; --i > 0 ; bh = bhnext) {
-			if(!bh)
-				break;
-
-			bhnext = bh->b_next_free; 
+		if (!bh)
+			continue;
+		for (i = nr_buffers_type[nlist] ; i > 0 ;
+		     bh = bhnext, i--)
+		{
+			bhnext = bh->b_next_free;
 			if (bh->b_dev != dev)
-				 continue;
-			if (bh->b_size == size)
-				 continue;
-			bhnext->b_count++;
-			wait_on_buffer(bh);
-			bhnext->b_count--;
-			if (bh->b_dev == dev && bh->b_size != size) {
-				clear_bit(BH_Dirty, &bh->b_state);
-				clear_bit(BH_Uptodate, &bh->b_state);
-				clear_bit(BH_Req, &bh->b_state);
-				bh->b_flushtime = 0;
+				continue;
+			if (buffer_locked(bh))
+			{
+				slept = 1;
+				wait_on_buffer(bh);
 			}
-			remove_from_queues(bh);
-			bh->b_dev=B_FREE;
-			insert_into_queues(bh);
+			if (bh->b_dev != dev)
+				goto panic_changed;
+			if (!bh->b_count)
+				put_last_free(bh);
+			if (slept)
+				goto again;
 		}
 	}
+	return;
+
+ panic_changed:
+	panic("invalidate_buffers: buffer changed under us");
 }
 
-#else
 void set_blocksize(kdev_t dev, int size)
 {
 	extern int *blksize_size[];
-	int i, nlist;
+	int i, nlist, slept;
 	struct buffer_head * bh, *bhnext;
 
 	if (!blksize_size[MAJOR(dev)])
@@ -679,52 +639,42 @@
 	/* We need to be quite careful how we do this - we are moving entries
 	 * around on the free list, and we can get in a loop if we are not careful.
 	 */
+ again:
+	slept = 0;
 	for(nlist = 0; nlist < NR_LIST; nlist++) {
 		bh = lru_list[nlist];
-		for (i = nr_buffers_type[nlist]*2 ; --i > 0 ; bh = bhnext) {
-			if(!bh)
-				break;
-
-			bhnext = bh->b_next_free; 
-			if (bh->b_dev != dev)
-				 continue;
-			if (bh->b_size == size)
+		if (!bh)
+			continue;
+		for (i = nr_buffers_type[nlist] ; i > 0 ;
+		     bh = bhnext, i--)
+		{
+			bhnext = bh->b_next_free;
+			if (bh->b_dev != dev || bh->b_size == size)
 				 continue;
-			if (bhnext)
-				bhnext->b_count++;
-			wait_on_buffer(bh);
-			if (bh->b_dev == dev && bh->b_size != size) {
-				clear_bit(BH_Dirty, &bh->b_state);
-				clear_bit(BH_Uptodate, &bh->b_state);
-				clear_bit(BH_Req, &bh->b_state);
-				bh->b_flushtime = 0;
+			if (buffer_locked(bh))
+			{
+				slept = 1;
+				wait_on_buffer(bh);
 			}
-
-			/*
-			 * lets be mega-conservative about what to free:
-			 */
-			if (!(bh->b_dev != dev) && 
-				!(bh->b_size == size) &&
-				!bh->b_count &&
-				!buffer_protected(bh) &&
-				!buffer_dirty(bh) &&
-				!buffer_locked(bh) &&
-				!waitqueue_active(&bh->b_wait)) {
-					remove_from_hash_queue(bh);
-					bh->b_dev = NODEV;
-					refile_buffer(bh);
-					try_to_free_buffers(buffer_page(bh));
-			} else {
-				remove_from_queues(bh);
-				bh->b_dev=B_FREE;
-				insert_into_queues(bh);
-			}
-			if (bhnext)
-				bhnext->b_count--;
+			if (bh->b_dev != dev || bh->b_size == size)
+				goto panic_changed;
+			if (!bh->b_count)
+				put_last_free(bh);
+			else
+				printk(KERN_ERR
+				       "set_blocksize: "
+				       "b_count %d, dev %s, block %lu!\n",
+				       bh->b_count, bdevname(bh->b_dev),
+				       bh->b_blocknr);
+			if (slept)
+				goto again;
 		}
 	}
+	return;
+
+ panic_changed:
+	panic("set_blocksize: buffer changed under us");
 }
-#endif
 
 /*
 * This function knows that we do a linear pass over the whole array,
@@ -741,17 +691,11 @@
 	/*
 	 * We are up to something dangerous ... rather be careful
 	 */
-	if ((bh->b_count != 1) || buffer_protected(bh) ||
-			buffer_dirty(bh) || buffer_locked(bh) ||
-			!buffer_lowprio(bh) || waitqueue_active(&bh->b_wait)) {
-		brelse(bh);
-	} else {
-		bh->b_count--;
-		remove_from_hash_queue(bh);
-		bh->b_dev = NODEV;
-		refile_buffer(bh);
-		try_to_free_buffers(buffer_page(bh));
-	}
+	if (buffer_protected(bh) || buffer_dirty(bh) ||
+	    !buffer_lowprio(bh))
+		__brelse(bh);
+	else
+		__bforget(bh);
 }
 
 /*
@@ -929,9 +873,6 @@
 		__brelse(buf);
 		return;
 	}
-	buf->b_count = 0;
-	buf->b_state = 0;
-	remove_from_queues(buf);
 	put_last_free(buf);
 }