From fd30f6fd77b232b2da9b9bbecfcf92b8973d15f5 Mon Sep 17 00:00:00 2001
From: adilger <adilger>
Date: Tue, 7 Mar 2000 20:58:16 +0000
Subject: [PATCH] obdfs/flushd.c: added constant for nr_free_buffer_pages()
 function call as     this isn't available from the kernel.  Will figure out
 later. obdfs/rw.c: added bit on page flags to indicate if page is in obdfs
 page     cache, to avoid searching list when inserting pages to page cache

---
 lustre/include/linux/obdfs.h | 18 ++++++++++++++++++
 lustre/obdclass/obdcontrol   |  2 +-
 lustre/obdfs/flushd.c        |  8 +++++---
 lustre/obdfs/rw.c            | 17 ++++++++++-------
 4 files changed, 34 insertions(+), 11 deletions(-)

diff --git a/lustre/include/linux/obdfs.h b/lustre/include/linux/obdfs.h
index 0ce8157..2359995 100644
--- a/lustre/include/linux/obdfs.h
+++ b/lustre/include/linux/obdfs.h
@@ -145,6 +145,14 @@ static inline struct list_head *obdfs_slist(struct inode *inode)
 	/* CDEBUG(D_INFO, "free lock\n"); */ \
 }
 
+/* We track if a page has been added to the OBD page cache by stting a
+ * flag on the page.  We have chosen a bit that will hopefully not be
+ * used for a while.
+ */
+#define PG_obdcache 29
+#define OBDAddCachePage(page)	test_and_set_bit(PG_obdcache, &(page)->flags)
+#define OBDClearCachePage(page)	clear_bit(PG_obdcache, &(page)->flags)
+
 static inline void obdfs_print_plist(struct inode *inode) 
 {
 	struct list_head *page_list = obdfs_iplist(inode);
@@ -194,6 +202,16 @@ static void inline obdfs_to_inode(struct inode *inode, struct obdo *oa)
 
 	CDEBUG(D_INFO, "src obdo %ld valid 0x%08x, dst inode %ld\n",
 	       (long)oa->o_id, oa->o_valid, inode->i_ino);
+	/* If the inode is dirty, we won't overwrite the data there, as it
+	 * is newer than the data on the disk.  The ext2obd side only will
+	 * change the block count, so we are guaranteed that is safe.
+	 */
+	if (inode->i_state & I_DIRTY) {
+		CDEBUG(D_INODE, "dirty inode %ld, only copying blocks\n",
+		       inode->i_ino);
+		oa->o_valid = OBD_MD_FLBLOCKS;
+	}
+
 	obdo_to_inode(inode, oa);
 
 	if (obdo_has_inline(oa)) {
diff --git a/lustre/obdclass/obdcontrol b/lustre/obdclass/obdcontrol
index 0e11f78..59dda5a 100755
--- a/lustre/obdclass/obdcontrol
+++ b/lustre/obdclass/obdcontrol
@@ -1290,7 +1290,7 @@ sub Punch {
 	return;
     }
 
-    print("Punching $count bytes starting at byte $start in object $id...\n");
+    print("Punching $count bytes starting at byte $start from object $id...\n");
 
     my $obdo;
     $obdo->{id} = $id;
diff --git a/lustre/obdfs/flushd.c b/lustre/obdfs/flushd.c
index f13952c..638dd54 100644
--- a/lustre/obdfs/flushd.c
+++ b/lustre/obdfs/flushd.c
@@ -17,6 +17,11 @@
 #include <linux/obdfs.h>
 
 
+/* XXX temporary until the real function is available from kernel
+ * XXX set this to memory size in pages for max page cache size
+ */
+#define nr_free_buffer_pages() 32768
+
 struct {
 	int nfract;  /* Percentage of buffer cache dirty to 
 			activate bdflush */
@@ -366,10 +371,7 @@ static int pupdate(void *unused)
 		/* asynchronous setattr etc for the future ...
 		obdfs_flush_dirty_inodes(jiffies - pupd_prm.age_super);
 		 */
-		/* XXX for debugging
 		dirty_limit = nr_free_buffer_pages() * pupd_prm.nfract / 100;
-		 * XXX */
-		dirty_limit = 16384 * pupd_prm.nfract / 100;
 		CDEBUG(D_CACHE, "dirty_limit %ld, cache_count %ld, wrote %d\n",
 		       dirty_limit, obdfs_cache_count, wrote);
 
diff --git a/lustre/obdfs/rw.c b/lustre/obdfs/rw.c
index be52f79..7a2dab7 100644
--- a/lustre/obdfs/rw.c
+++ b/lustre/obdfs/rw.c
@@ -121,6 +121,7 @@ inline void obdfs_pgrq_del(struct obdfs_pgrq *pgrq)
 	--obdfs_cache_count;
 	CDEBUG(D_INFO, "deleting page %p from list [count %ld]\n",
 	       pgrq->rq_page, obdfs_cache_count);
+	OBDClearCachePage(pgrq->rq_page);
 	list_del(&pgrq->rq_plist);
 	kmem_cache_free(obdfs_pgrq_cachep, pgrq);
 }
@@ -143,12 +144,13 @@ void obdfs_cleanup_pgrqcache(void)
 
 
 /*
- * Find a specific page in the page cache.  If it is found, we return
- * the write request struct associated with it, if not found return NULL.
+ * See whether a specific page in the page cache.
  * Called with the list lock held.
  */
-static struct obdfs_pgrq *
-obdfs_find_in_page_list(struct inode *inode, struct page *page)
+#ifdef PG_obdcache
+#define obdfs_find_in_page_list(inode, page) OBDAddCachePage(page)
+#else
+static int obdfs_find_in_page_list(struct inode *inode, struct page *page)
 {
 	struct list_head *page_list = obdfs_iplist(inode);
 	struct list_head *tmp;
@@ -161,7 +163,7 @@ obdfs_find_in_page_list(struct inode *inode, struct page *page)
 	if (list_empty(page_list)) {
 		CDEBUG(D_INFO, "empty list\n");
 		EXIT;
-		return NULL;
+		return 0;
 	}
 	tmp = page_list;
 	while ( (tmp = tmp->next) != page_list ) {
@@ -171,13 +173,14 @@ obdfs_find_in_page_list(struct inode *inode, struct page *page)
 		if (pgrq->rq_page == page) {
 			CDEBUG(D_INFO, "found page %p in list\n", page);
 			EXIT;
-			return pgrq;
+			return 1;
 		}
 	} 
 
 	EXIT;
-	return NULL;
+	return 0;
 } /* obdfs_find_in_page_list */
+#endif
 
 
 /* called with the list lock held */
-- 
1.8.3.1