X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=fs%2Fbuffer.c;h=1d0852fa728bd851969e93a9f9cfcf4fea6010bc;hb=771b8dad9653d2659e0ffcc237184cb16c317788;hp=7ff6e9346faed9f149948b8756934afbf79b9af6;hpb=c827ba4cb49a30ce581201fd0ba2be77cde412c7;p=powerpc.git

diff --git a/fs/buffer.c b/fs/buffer.c
index 7ff6e9346f..1d0852fa72 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1283,11 +1283,11 @@ static void bh_lru_install(struct buffer_head *bh)
  * Look up the bh in this cpu's LRU.  If it's there, move it to the head.
  */
 static struct buffer_head *
-lookup_bh_lru(struct block_device *bdev, sector_t block, int size)
+lookup_bh_lru(struct block_device *bdev, sector_t block, unsigned size)
 {
 	struct buffer_head *ret = NULL;
 	struct bh_lru *lru;
-	int i;
+	unsigned int i;
 
 	check_irqs_on();
 	bh_lru_lock();
@@ -1319,7 +1319,7 @@ lookup_bh_lru(struct block_device *bdev, sector_t block, int size)
  * NULL
  */
 struct buffer_head *
-__find_get_block(struct block_device *bdev, sector_t block, int size)
+__find_get_block(struct block_device *bdev, sector_t block, unsigned size)
 {
 	struct buffer_head *bh = lookup_bh_lru(bdev, block, size);
 
@@ -1347,7 +1347,7 @@ EXPORT_SYMBOL(__find_get_block);
  * attempt is failing.  FIXME, perhaps?
  */
 struct buffer_head *
-__getblk(struct block_device *bdev, sector_t block, int size)
+__getblk(struct block_device *bdev, sector_t block, unsigned size)
 {
 	struct buffer_head *bh = __find_get_block(bdev, block, size);
 
@@ -1361,7 +1361,7 @@ EXPORT_SYMBOL(__getblk);
 /*
  * Do async read-ahead on a buffer..
  */
-void __breadahead(struct block_device *bdev, sector_t block, int size)
+void __breadahead(struct block_device *bdev, sector_t block, unsigned size)
 {
 	struct buffer_head *bh = __getblk(bdev, block, size);
 	if (likely(bh)) {
@@ -1381,7 +1381,7 @@ EXPORT_SYMBOL(__breadahead);
  *  It returns NULL if the block was unreadable.
  */
 struct buffer_head *
-__bread(struct block_device *bdev, sector_t block, int size)
+__bread(struct block_device *bdev, sector_t block, unsigned size)
 {
 	struct buffer_head *bh = __getblk(bdev, block, size);
 
@@ -1440,6 +1440,7 @@ static void discard_buffer(struct buffer_head * bh)
 	clear_buffer_req(bh);
 	clear_buffer_new(bh);
 	clear_buffer_delay(bh);
+	clear_buffer_unwritten(bh);
 	unlock_buffer(bh);
 }
 
@@ -1742,7 +1743,6 @@ recover:
 	SetPageError(page);
 	BUG_ON(PageWriteback(page));
 	set_page_writeback(page);
-	unlock_page(page);
 	do {
 		struct buffer_head *next = bh->b_this_page;
 		if (buffer_async_write(bh)) {
@@ -1752,6 +1752,7 @@ recover:
 		}
 		bh = next;
 	} while (bh != head);
+	unlock_page(page);
 	goto done;
 }
 
@@ -1823,6 +1824,7 @@ static int __block_prepare_write(struct inode *inode, struct page *page,
 			continue; 
 		}
 		if (!buffer_uptodate(bh) && !buffer_delay(bh) &&
+		    !buffer_unwritten(bh) &&
 		     (block_start < from || block_end > to)) {
 			ll_rw_block(READ, 1, &bh);
 			*wait_bh++=bh;
@@ -2246,7 +2248,6 @@ int nobh_prepare_write(struct page *page, unsigned from, unsigned to,
 	int i;
 	int ret = 0;
 	int is_mapped_to_disk = 1;
-	int dirtied_it = 0;
 
 	if (PageMappedToDisk(page))
 		return 0;
@@ -2283,14 +2284,10 @@ int nobh_prepare_write(struct page *page, unsigned from, unsigned to,
 			continue;
 		if (buffer_new(&map_bh) || !buffer_mapped(&map_bh)) {
 			kaddr = kmap_atomic(page, KM_USER0);
-			if (block_start < from) {
+			if (block_start < from)
 				memset(kaddr+block_start, 0, from-block_start);
-				dirtied_it = 1;
-			}
-			if (block_end > to) {
+			if (block_end > to)
 				memset(kaddr + to, 0, block_end - to);
-				dirtied_it = 1;
-			}
 			flush_dcache_page(page);
 			kunmap_atomic(kaddr, KM_USER0);
 			continue;
@@ -2345,17 +2342,6 @@ int nobh_prepare_write(struct page *page, unsigned from, unsigned to,
 
 	if (is_mapped_to_disk)
 		SetPageMappedToDisk(page);
-	SetPageUptodate(page);
-
-	/*
-	 * Setting the page dirty here isn't necessary for the prepare_write
-	 * function - commit_write will do that.  But if/when this function is
-	 * used within the pagefault handler to ensure that all mmapped pages
-	 * have backing space in the filesystem, we will need to dirty the page
-	 * if its contents were altered.
-	 */
-	if (dirtied_it)
-		set_page_dirty(page);
 
 	return 0;
 
@@ -2379,12 +2365,17 @@ failed:
 }
 EXPORT_SYMBOL(nobh_prepare_write);
 
+/*
+ * Make sure any changes to nobh_commit_write() are reflected in
+ * nobh_truncate_page(), since it doesn't call commit_write().
+ */
 int nobh_commit_write(struct file *file, struct page *page,
 		unsigned from, unsigned to)
 {
 	struct inode *inode = page->mapping->host;
 	loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
 
+	SetPageUptodate(page);
 	set_page_dirty(page);
 	if (pos > inode->i_size) {
 		i_size_write(inode, pos);
@@ -2479,6 +2470,11 @@ int nobh_truncate_page(struct address_space *mapping, loff_t from)
 		memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
 		flush_dcache_page(page);
 		kunmap_atomic(kaddr, KM_USER0);
+		/*
+		 * It would be more correct to call aops->commit_write()
+		 * here, but this is more efficient.
+		 */
+		SetPageUptodate(page);
 		set_page_dirty(page);
 	}
 	unlock_page(page);
@@ -2544,7 +2540,7 @@ int block_truncate_page(struct address_space *mapping,
 	if (PageUptodate(page))
 		set_buffer_uptodate(bh);
 
-	if (!buffer_uptodate(bh) && !buffer_delay(bh)) {
+	if (!buffer_uptodate(bh) && !buffer_delay(bh) && !buffer_unwritten(bh)) {
 		err = -EIO;
 		ll_rw_block(READ, 1, &bh);
 		wait_on_buffer(bh);