Revert "fb_defio: fix for non-dirty ptes"

[pandora-kernel.git] / drivers / video / fb_defio.c

diff --git a/drivers/video/fb_defio.c b/drivers/video/fb_defio.c
index 1105a59..137100e 100644 (file)
--- a/drivers/video/fb_defio.c
+++ b/drivers/video/fb_defio.c
@@ -66,7 +66,7 @@ static int fb_deferred_io_fault(struct vm_area_struct *vma,
        return 0;
 }
 
-int fb_deferred_io_fsync(struct file *file, struct dentry *dentry, int datasync)
+int fb_deferred_io_fsync(struct file *file, int datasync)
 {
        struct fb_info *info = file->private_data;
 
@@ -155,41 +155,25 @@ static void fb_deferred_io_work(struct work_struct *work)
 {
        struct fb_info *info = container_of(work, struct fb_info,
                                                deferred_work.work);
+       struct list_head *node, *next;
+       struct page *cur;
        struct fb_deferred_io *fbdefio = info->fbdefio;
-       struct page *page, *tmp_page;
-       struct list_head *node, *tmp_node;
-       struct list_head non_dirty;
-
-       INIT_LIST_HEAD(&non_dirty);
 
        /* here we mkclean the pages, then do all deferred IO */
        mutex_lock(&fbdefio->lock);
-       list_for_each_entry_safe(page, tmp_page, &fbdefio->pagelist, lru) {
-               lock_page(page);
-               /*
-                * The workqueue callback can be triggered after a
-                * ->page_mkwrite() call but before the PTE has been marked
-                * dirty. In this case page_mkclean() won't "rearm" the page.
-                *
-                * To avoid this, remove those "non-dirty" pages from the
-                * pagelist before calling the driver's callback, then add
-                * them back to get processed on the next work iteration.
-                * At that time, their PTEs will hopefully be dirty for real.
-                */
-               if (!page_mkclean(page))
-                       list_move_tail(&page->lru, &non_dirty);
-               unlock_page(page);
+       list_for_each_entry(cur, &fbdefio->pagelist, lru) {
+               lock_page(cur);
+               page_mkclean(cur);
+               unlock_page(cur);
        }
 
        /* driver's callback with pagelist */
        fbdefio->deferred_io(info, &fbdefio->pagelist);
 
-       /* clear the list... */
-       list_for_each_safe(node, tmp_node, &fbdefio->pagelist) {
+       /* clear the list */
+       list_for_each_safe(node, next, &fbdefio->pagelist) {
                list_del(node);
        }
-       /* ... and add back the "non-dirty" pages to the list */
-       list_splice_tail(&non_dirty, &fbdefio->pagelist);
        mutex_unlock(&fbdefio->lock);
 }
 
@@ -218,7 +202,6 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_open);
 void fb_deferred_io_cleanup(struct fb_info *info)
 {
        struct fb_deferred_io *fbdefio = info->fbdefio;
-       struct list_head *node, *tmp_node;
        struct page *page;
        int i;
 
@@ -226,13 +209,6 @@ void fb_deferred_io_cleanup(struct fb_info *info)
        cancel_delayed_work(&info->deferred_work);
        flush_scheduled_work();
 
-       /*  the list may have still some non-dirty pages at this point */
-       mutex_lock(&fbdefio->lock);
-       list_for_each_safe(node, tmp_node, &fbdefio->pagelist) {
-               list_del(node);
-       }
-       mutex_unlock(&fbdefio->lock);
-
        /* clear out the mapping that we setup */
        for (i = 0 ; i < info->fix.smem_len; i += PAGE_SIZE) {
                page = fb_deferred_io_page(info, i);