X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=mm%2Ffilemap.c;h=876bc595d0f8b3b3e4f626bf1ad7acbb657bdc66;hb=2075eb8d95612cadde91ef5be82691d97a2ea6c5;hp=42bbc6909ba4852ac41506b175584ba4d00e32eb;hpb=8ab22b9abb5c55413802e4adc9aa6223324547c3;p=linux-2.6-omap-h63xx.git

diff --git a/mm/filemap.c b/mm/filemap.c
index 42bbc6909ba..876bc595d0f 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -558,14 +558,14 @@ EXPORT_SYMBOL(wait_on_page_bit);
  * But that's OK - sleepers in wait_on_page_writeback() just go back to sleep.
  *
  * The first mb is necessary to safely close the critical section opened by the
- * TestSetPageLocked(), the second mb is necessary to enforce ordering between
- * the clear_bit and the read of the waitqueue (to avoid SMP races with a
- * parallel wait_on_page_locked()).
+ * test_and_set_bit() to lock the page; the second mb is necessary to enforce
+ * ordering between the clear_bit and the read of the waitqueue (to avoid SMP
+ * races with a parallel wait_on_page_locked()).
  */
 void unlock_page(struct page *page)
 {
 	smp_mb__before_clear_bit();
-	if (!TestClearPageLocked(page))
+	if (!test_and_clear_bit(PG_locked, &page->flags))
 		BUG();
 	smp_mb__after_clear_bit(); 
 	wake_up_page(page, PG_locked);
@@ -931,7 +931,7 @@ grab_cache_page_nowait(struct address_space *mapping, pgoff_t index)
 	struct page *page = find_get_page(mapping, index);
 
 	if (page) {
-		if (!TestSetPageLocked(page))
+		if (trylock_page(page))
 			return page;
 		page_cache_release(page);
 		return NULL;
@@ -1027,7 +1027,7 @@ find_page:
 			if (inode->i_blkbits == PAGE_CACHE_SHIFT ||
 					!mapping->a_ops->is_partially_uptodate)
 				goto page_not_up_to_date;
-			if (TestSetPageLocked(page))
+			if (!trylock_page(page))
 				goto page_not_up_to_date;
 			if (!mapping->a_ops->is_partially_uptodate(page,
 								desc, offset))
@@ -1879,7 +1879,7 @@ void iov_iter_advance(struct iov_iter *i, size_t bytes)
 		 * The !iov->iov_len check ensures we skip over unlikely
 		 * zero-length segments (without overruning the iovec).
 		 */
-		while (bytes || unlikely(!iov->iov_len && i->count)) {
+		while (bytes || unlikely(i->count && !iov->iov_len)) {
 			int copy;
 
 			copy = min(bytes, iov->iov_len - base);
@@ -2129,13 +2129,20 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
 	 * After a write we want buffered reads to be sure to go to disk to get
 	 * the new data.  We invalidate clean cached page from the region we're
 	 * about to write.  We do this *before* the write so that we can return
-	 * -EIO without clobbering -EIOCBQUEUED from ->direct_IO().
+	 * without clobbering -EIOCBQUEUED from ->direct_IO().
 	 */
 	if (mapping->nrpages) {
 		written = invalidate_inode_pages2_range(mapping,
 					pos >> PAGE_CACHE_SHIFT, end);
-		if (written)
+		/*
+		 * If a page can not be invalidated, return 0 to fall back
+		 * to buffered write.
+		 */
+		if (written) {
+			if (written == -EBUSY)
+				return 0;
 			goto out;
+		}
 	}
 
 	written = mapping->a_ops->direct_IO(WRITE, iocb, iov, pos, *nr_segs);