- don't read the page if we're just about to completely overwrite it

- fixed one of the page invariant BUGs

diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c
index aa1d9e3..12814a4 100644 (file)
--- a/lustre/llite/rw.c
+++ b/lustre/llite/rw.c
@@ -241,12 +241,19 @@ static int ll_prepare_write(struct file *file, struct page *page, unsigned from,
                goto prepare_done;
         }
 
-        if ( offset + from >= inode->i_size ) {
-               memset(addr, 0, PAGE_SIZE); 
+        if (offset + from >= inode->i_size) {
+               memset(addr, 0, PAGE_SIZE);
                 EXIT;
                 goto prepare_done;
         }
-        
+
+       /* We're completely overwriting an existing page, so _don't_ set it up
+        * to date until commit_write */
+       if (from == 0 && to == PAGE_SIZE) {
+               memset(addr, 0, PAGE_SIZE);
+               RETURN(0);
+       }
+
         rc = ll_brw(OBD_BRW_READ, inode, page, 0);
 
  prepare_done:
@@ -299,14 +306,13 @@ static int ll_commit_write(struct file *file, struct page *page,
 
         ENTRY;
         oa = ll_oa_from_inode(inode, OBD_MD_FLNOTOBD);
-       if (! oa ) { 
-               return -ENOMEM;
-       }
+       if (! oa )
+               RETURN(-ENOMEM);
+
+       SetPageUptodate(page);
 
         if (!PageLocked(page))
                 BUG();
-        if (!Page_Uptodate(page))
-                BUG(); 
 
        CDEBUG(D_INODE, "commit_page writing (at %d) to %d, count %Ld\n", 
               from, to, count);