fbdev: move fbdev core files to separate directory

Instead of having fbdev framework core files at the root fbdev
directory, mixed with random fbdev device drivers, move the fbdev core
files to a separate core directory. This makes it much clearer which of
the files are actually part of the fbdev framework, and which are part
of device drivers.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 245 insertions, 0 deletions

diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
new file mode 100644
index 000000000000..900aa4ecd617
--- /dev/null
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -0,0 +1,245 @@
+/*
+ *  linux/drivers/video/fb_defio.c
+ *
+ *  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
+ * for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/fb.h>
+#include <linux/list.h>
+
+/* to support deferred IO */
+#include <linux/rmap.h>
+#include <linux/pagemap.h>
+
+static 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 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;
+
+	offset = vmf->pgoff << PAGE_SHIFT;
+	if (offset >= info->fix.smem_len)
+		return VM_FAULT_SIGBUS;
+
+	page = fb_deferred_io_page(info, offset);
+	if (!page)
+		return VM_FAULT_SIGBUS;
+
+	get_page(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, loff_t start, loff_t end, int datasync)
+{
+	struct fb_info *info = file->private_data;
+	struct inode *inode = file_inode(file);
+	int err = filemap_write_and_wait_range(inode->i_mapping, start, end);
+	if (err)
+		return err;
+
+	/* Skip if deferred io is compiled-in but disabled on this fbdev */
+	if (!info->fbdefio)
+		return 0;
+
+	mutex_lock(&inode->i_mutex);
+	/* Kill off the delayed work */
+	cancel_delayed_work_sync(&info->deferred_work);
+
+	/* Run it immediately */
+	err = schedule_delayed_work(&info->deferred_work, 0);
+	mutex_unlock(&inode->i_mutex);
+	return err;
+}
+EXPORT_SYMBOL_GPL(fb_deferred_io_fsync);
+
+/* vm_ops->page_mkwrite handler */
+static int fb_deferred_io_mkwrite(struct vm_area_struct *vma,
+				  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
+	will eventually mkclean the touched pages and execute the
+	deferred framebuffer IO. then if userspace touches a page
+	again, we repeat the same scheme */
+
+	file_update_time(vma->vm_file);
+
+	/* protect against the workqueue changing the page list */
+	mutex_lock(&fbdefio->lock);
+
+	/* first write in this cycle, notify the driver */
+	if (fbdefio->first_io && list_empty(&fbdefio->pagelist))
+		fbdefio->first_io(info);
+
+	/*
+	 * We want the page to remain locked from ->page_mkwrite until
+	 * the PTE is marked dirty to avoid page_mkclean() being called
+	 * before the PTE is updated, which would leave the page ignored
+	 * by defio.
+	 * Do this by locking the page here and informing the caller
+	 * about it with VM_FAULT_LOCKED.
+	 */
+	lock_page(page);
+
+	/* 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 */
+	schedule_delayed_work(&info->deferred_work, fbdefio->delay);
+	return VM_FAULT_LOCKED;
+}
+
+static const struct vm_operations_struct fb_deferred_io_vm_ops = {
+	.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;
+	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
+	if (!(info->flags & FBINFO_VIRTFB))
+		vma->vm_flags |= VM_IO;
+	vma->vm_private_data = info;
+	return 0;
+}
+
+/* workqueue callback */
+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;
+
+	/* here we mkclean the pages, then do all deferred IO */
+	mutex_lock(&fbdefio->lock);
+	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, next, &fbdefio->pagelist) {
+		list_del(node);
+	}
+	mutex_unlock(&fbdefio->lock);
+}
+
+void fb_deferred_io_init(struct fb_info *info)
+{
+	struct fb_deferred_io *fbdefio = info->fbdefio;
+
+	BUG_ON(!fbdefio);
+	mutex_init(&fbdefio->lock);
+	info->fbops->fb_mmap = fb_deferred_io_mmap;
+	INIT_DELAYED_WORK(&info->deferred_work, fb_deferred_io_work);
+	INIT_LIST_HEAD(&fbdefio->pagelist);
+	if (fbdefio->delay == 0) /* set a default of 1 s */
+		fbdefio->delay = HZ;
+}
+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_sync(&info->deferred_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);
+
+MODULE_LICENSE("GPL");