X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=drivers%2Fvideo%2Ffb_defio.c;h=0a7a6679ee6eb05e2be754ff816ba3547a0f7fdb;hb=8259cf4342029aad37660e524178c8858f48b0ab;hp=a0c5d9d90d741499e5cdb6087d138337c494b3e9;hpb=84902b7af642c86a518c17629c0dbe705a4b6d14;p=safe%2Fjmp%2Flinux-2.6

diff --git a/drivers/video/fb_defio.c b/drivers/video/fb_defio.c
index a0c5d9d..0a7a667 100644
--- a/drivers/video/fb_defio.c
+++ b/drivers/video/fb_defio.c
@@ -4,7 +4,7 @@
  *  Copyright (C) 2006 Jaya Kumar
  *
  * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file COPYING in the main directory of this archive
+ * License. See the file COPYING in the main directory of this archive
  * for more details.
  */
 
@@ -24,34 +24,57 @@
 #include <linux/rmap.h>
 #include <linux/pagemap.h>
 
+struct page *fb_deferred_io_page(struct fb_info *info, unsigned long offs)
+{
+	void *screen_base = (void __force *) info->screen_base;
+	struct page *page;
+
+	if (is_vmalloc_addr(screen_base + offs))
+		page = vmalloc_to_page(screen_base + offs);
+	else
+		page = pfn_to_page((info->fix.smem_start + offs) >> PAGE_SHIFT);
+
+	return page;
+}
+
 /* this is to find and return the vmalloc-ed fb pages */
-static struct page* fb_deferred_io_nopage(struct vm_area_struct *vma,
-					unsigned long vaddr, int *type)
+static int fb_deferred_io_fault(struct vm_area_struct *vma,
+				struct vm_fault *vmf)
 {
 	unsigned long offset;
 	struct page *page;
 	struct fb_info *info = vma->vm_private_data;
-	/* info->screen_base is in System RAM */
-	void *screen_base = (void __force *) info->screen_base;
 
-	offset = (vaddr - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT);
+	offset = vmf->pgoff << PAGE_SHIFT;
 	if (offset >= info->fix.smem_len)
-		return NOPAGE_SIGBUS;
+		return VM_FAULT_SIGBUS;
 
-	page = vmalloc_to_page(screen_base + offset);
+	page = fb_deferred_io_page(info, offset);
 	if (!page)
-		return NOPAGE_OOM;
+		return VM_FAULT_SIGBUS;
 
 	get_page(page);
-	if (type)
-		*type = VM_FAULT_MINOR;
-	return page;
+
+	if (vma->vm_file)
+		page->mapping = vma->vm_file->f_mapping;
+	else
+		printk(KERN_ERR "no mapping available\n");
+
+	BUG_ON(!page->mapping);
+	page->index = vmf->pgoff;
+
+	vmf->page = page;
+	return 0;
 }
 
 int fb_deferred_io_fsync(struct file *file, struct dentry *dentry, int datasync)
 {
 	struct fb_info *info = file->private_data;
 
+	/* Skip if deferred io is complied-in but disabled on this fbdev */
+	if (!info->fbdefio)
+		return 0;
+
 	/* Kill off the delayed work */
 	cancel_rearming_delayed_work(&info->deferred_work);
 
@@ -62,10 +85,12 @@ EXPORT_SYMBOL_GPL(fb_deferred_io_fsync);
 
 /* vm_ops->page_mkwrite handler */
 static int fb_deferred_io_mkwrite(struct vm_area_struct *vma,
-				  struct page *page)
+				  struct vm_fault *vmf)
 {
+	struct page *page = vmf->page;
 	struct fb_info *info = vma->vm_private_data;
 	struct fb_deferred_io *fbdefio = info->fbdefio;
+	struct page *cur;
 
 	/* this is a callback we get when userspace first tries to
 	write to the page. we schedule a workqueue. that workqueue
@@ -75,7 +100,24 @@ static int fb_deferred_io_mkwrite(struct vm_area_struct *vma,
 
 	/* protect against the workqueue changing the page list */
 	mutex_lock(&fbdefio->lock);
-	list_add(&page->lru, &fbdefio->pagelist);
+
+	/* we loop through the pagelist before adding in order
+	to keep the pagelist sorted */
+	list_for_each_entry(cur, &fbdefio->pagelist, lru) {
+		/* this check is to catch the case where a new
+		process could start writing to the same page
+		through a new pte. this new access can cause the
+		mkwrite even when the original ps's pte is marked
+		writable */
+		if (unlikely(cur == page))
+			goto page_already_added;
+		else if (cur->index > page->index)
+			break;
+	}
+
+	list_add_tail(&page->lru, &cur->lru);
+
+page_already_added:
 	mutex_unlock(&fbdefio->lock);
 
 	/* come back after delay to process the deferred IO */
@@ -84,10 +126,21 @@ static int fb_deferred_io_mkwrite(struct vm_area_struct *vma,
 }
 
 static struct vm_operations_struct fb_deferred_io_vm_ops = {
-	.nopage   	= fb_deferred_io_nopage,
+	.fault		= fb_deferred_io_fault,
 	.page_mkwrite	= fb_deferred_io_mkwrite,
 };
 
+static int fb_deferred_io_set_page_dirty(struct page *page)
+{
+	if (!PageDirty(page))
+		SetPageDirty(page);
+	return 0;
+}
+
+static const struct address_space_operations fb_deferred_io_aops = {
+	.set_page_dirty = fb_deferred_io_set_page_dirty,
+};
+
 static int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
 	vma->vm_ops = &fb_deferred_io_vm_ops;
@@ -137,13 +190,32 @@ void fb_deferred_io_init(struct fb_info *info)
 }
 EXPORT_SYMBOL_GPL(fb_deferred_io_init);
 
+void fb_deferred_io_open(struct fb_info *info,
+			 struct inode *inode,
+			 struct file *file)
+{
+	file->f_mapping->a_ops = &fb_deferred_io_aops;
+}
+EXPORT_SYMBOL_GPL(fb_deferred_io_open);
+
 void fb_deferred_io_cleanup(struct fb_info *info)
 {
 	struct fb_deferred_io *fbdefio = info->fbdefio;
+	struct page *page;
+	int i;
 
 	BUG_ON(!fbdefio);
 	cancel_delayed_work(&info->deferred_work);
 	flush_scheduled_work();
+
+	/* 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);
+		page->mapping = NULL;
+	}
+
+	info->fbops->fb_mmap = NULL;
+	mutex_destroy(&fbdefio->lock);
 }
 EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);