fb: fsync() method for deferred I/O flush.

There are cases when we do not want to wait on the delay for automatically
updating the "real" framebuffer, this implements a simple ->fsync() hook
for explicitly flushing the deferred I/O work.  The ->page_mkwrite()
handler will rearm the work queue normally.

(akpm: nuke unneeded ifdefs, forward-delcare struct dentry)

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: Jaya Kumar <jayakumar.lkml@gmail.com>
Acked-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Paul Mundt 2007-05-08 00:37:41 -07:00 committed by Linus Torvalds
parent 7bf1ea33ad
commit 5e841b88d2
3 changed files with 19 additions and 2 deletions

View File

@ -47,6 +47,18 @@ static struct page* fb_deferred_io_nopage(struct vm_area_struct *vma,
return page;
}
int fb_deferred_io_fsync(struct file *file, struct dentry *dentry, int datasync)
{
struct fb_info *info = file->private_data;
/* Kill off the delayed work */
cancel_rearming_delayed_work(&info->deferred_work);
/* Run it immediately */
return schedule_delayed_work(&info->deferred_work, 0);
}
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)

View File

@ -1266,6 +1266,9 @@ static const struct file_operations fb_fops = {
#ifdef HAVE_ARCH_FB_UNMAPPED_AREA
.get_unmapped_area = get_fb_unmapped_area,
#endif
#ifdef CONFIG_FB_DEFERRED_IO
.fsync = fb_deferred_io_fsync,
#endif
};
struct class *fb_class;

View File

@ -4,6 +4,8 @@
#include <asm/types.h>
#include <linux/i2c.h>
struct dentry;
/* Definitions of frame buffers */
#define FB_MAJOR 29
@ -927,11 +929,11 @@ static inline void __fb_pad_aligned_buffer(u8 *dst, u32 d_pitch,
}
}
#ifdef CONFIG_FB_DEFERRED_IO
/* drivers/video/fb_defio.c */
extern void fb_deferred_io_init(struct fb_info *info);
extern void fb_deferred_io_cleanup(struct fb_info *info);
#endif
extern int fb_deferred_io_fsync(struct file *file, struct dentry *dentry,
int datasync);
/* drivers/video/fbsysfs.c */
extern struct fb_info *framebuffer_alloc(size_t size, struct device *dev);