diff -uNr 2.4.4-mSsu/fs/proc/proc_misc.c 2.4.4-mSsua/fs/proc/proc_misc.c
--- 2.4.4-mSsu/fs/proc/proc_misc.c	Sun Apr 29 20:32:52 2001
+++ 2.4.4-mSsua/fs/proc/proc_misc.c	Mon May  7 13:38:53 2001
@@ -140,6 +140,17 @@
 {
 	struct sysinfo i;
 	int len;
+	unsigned int cached, shmem;
+
+	/*
+	 * There may be some inconsistency because shmem_nrpages
+	 * update is delayed to page_cache_size
+	 * We make sure the cached value does not get below zero 
+	 */
+	cached = atomic_read(&page_cache_size);
+	shmem  = atomic_read(&shmem_nrpages);
+	if (shmem < cached)
+		cached -= shmem;
 
 /*
  * display in kilobytes.
@@ -153,8 +164,8 @@
                 "Swap: %8lu %8lu %8lu\n",
                 B(i.totalram), B(i.totalram-i.freeram), B(i.freeram),
                 B(i.sharedram), B(i.bufferram),
-                B(atomic_read(&page_cache_size)), B(i.totalswap),
-                B(i.totalswap-i.freeswap), B(i.freeswap));
+		B(cached), B(i.totalswap),
+		B(i.totalswap-i.freeswap), B(i.freeswap));
         /*
          * Tagged format, for easy grepping and expansion.
          * The above will go away eventually, once the tools
@@ -180,7 +191,7 @@
                 K(i.freeram),
                 K(i.sharedram),
                 K(i.bufferram),
-                K(atomic_read(&page_cache_size)),
+		K(cached),
 		K(nr_active_pages),
 		K(nr_inactive_dirty_pages),
 		K(nr_inactive_clean_pages()),
diff -uNr 2.4.4-mSsu/include/linux/shmem_fs.h 2.4.4-mSsua/include/linux/shmem_fs.h
--- 2.4.4-mSsu/include/linux/shmem_fs.h	Wed May  2 18:36:05 2001
+++ 2.4.4-mSsua/include/linux/shmem_fs.h	Mon May  7 12:52:00 2001
@@ -17,6 +17,8 @@
 	unsigned long val;
 } swp_entry_t;
 
+extern atomic_t shmem_nrpages;
+
 struct shmem_inode_info {
 	spinlock_t		lock;
 	struct semaphore 	sem;
diff -uNr 2.4.4-mSsu/mm/mmap.c 2.4.4-mSsua/mm/mmap.c
--- 2.4.4-mSsu/mm/mmap.c	Sun Apr 29 20:33:01 2001
+++ 2.4.4-mSsua/mm/mmap.c	Mon May  7 13:42:03 2001
@@ -55,13 +55,24 @@
 	 */
 
 	long free;
-	
+	unsigned long cached, shmem;
+
+	/*
+	 * There may be some inconsistency because shmem_nrpages
+	 * update is delayed to the page_cache_size
+	 * We make sure the cached value does not get below zero 
+	 */
+	cached = atomic_read(&page_cache_size);
+	shmem  = atomic_read(&shmem_nrpages);
+	if (cached > shmem)
+		cached -= shmem;
+
         /* Sometimes we want to use more memory than we have. */
 	if (sysctl_overcommit_memory)
 	    return 1;
 
 	free = atomic_read(&buffermem_pages);
-	free += atomic_read(&page_cache_size);
+	free += cached;
 	free += nr_free_pages();
 	free += nr_swap_pages;
 
diff -uNr 2.4.4-mSsu/mm/shmem.c 2.4.4-mSsua/mm/shmem.c
--- 2.4.4-mSsu/mm/shmem.c	Fri May  4 21:37:34 2001
+++ 2.4.4-mSsua/mm/shmem.c	Mon May  7 11:13:27 2001
@@ -3,7 +3,8 @@
  *
  * Copyright (C) 2000 Linus Torvalds.
  *		 2000 Transmeta Corp.
- *		 2000 Christoph Rohland
+ *		 2000-2001 Christoph Rohland
+ *		 2000-2001 SAP AG
  * 
  * This file is released under the GPL.
  */
@@ -45,6 +46,7 @@
 
 LIST_HEAD (shmem_inodes);
 static spinlock_t shmem_ilock = SPIN_LOCK_UNLOCKED;
+atomic_t shmem_nrpages = ATOMIC_INIT(0);
 
 #define BLOCKS_PER_PAGE (PAGE_SIZE/512)
 
@@ -52,6 +54,7 @@
  * shmem_recalc_inode - recalculate the size of an inode
  *
  * @inode: inode to recalc
+ * @swap:  additional swap pages freed externally
  *
  * We have to calculate the free blocks since the mm can drop pages
  * behind our back
@@ -62,12 +65,14 @@
  *
  * So the mm freed 
  * inodes->i_blocks/BLOCKS_PER_PAGE - 
- *			(inode->i_mapping->nrpages + info->swapped)
+ * 			(inode->i_mapping->nrpages + info->swapped)
  *
  * It has to be called with the spinlock held.
+ *
+ * The swap parameter is a performance hack for truncate.
  */
 
-static void shmem_recalc_inode(struct inode * inode)
+static void shmem_recalc_inode(struct inode * inode, unsigned long swap)
 {
 	unsigned long freed;
 
@@ -79,6 +84,7 @@
 		spin_lock (&info->stat_lock);
 		info->free_blocks += freed;
 		spin_unlock (&info->stat_lock);
+		atomic_sub(freed-swap, &shmem_nrpages);
 	}
 }
 
@@ -195,7 +201,7 @@
 out:
 	info->max_index = index;
 	info->swapped -= freed;
-	shmem_recalc_inode(inode);
+	shmem_recalc_inode(inode, freed);
 	spin_unlock (&info->lock);
 	up(&info->sem);
 }
@@ -250,14 +256,15 @@
 	entry = shmem_swp_entry(info, page->index);
 	if (IS_ERR(entry))	/* this had been allocted on page allocation */
 		BUG();
-	shmem_recalc_inode(page->mapping->host);
+	shmem_recalc_inode(page->mapping->host, 0);
 	error = -EAGAIN;
 	if (entry->val)
 		BUG();
 
 	*entry = swap;
 	error = 0;
-	/* Remove the from the page cache */
+	/* Remove the page from the page cache */
+	atomic_dec(&shmem_nrpages);
 	lru_cache_del(page);
 	remove_inode_page(page);
 
@@ -376,6 +383,7 @@
 	}
 
 	/* We have the page */
+	atomic_inc(&shmem_nrpages);
 	SetPageUptodate(page);
 	if (info->locked)
 		page_cache_get(page);
@@ -1275,6 +1283,7 @@
 	return 0;
 found:
 	add_to_page_cache(page, info->inode->i_mapping, offset + idx);
+	atomic_inc(&shmem_nrpages);
 	set_page_dirty(page);
 	SetPageUptodate(page);
 	UnlockPage(page);