fbdev/metronomefb: Generate deferred I/O ops

Use the existing generator macros to create deferred-I/O helpers
for metronomefb and set them in the fb_ops structure. Functions
for damage handling on memory ranges and areas are provided by
the driver.

Metronomefb's implementation of fb_write writes to system memory,
so the generated code can use the respective helper internally.
This also fixes a long-standing bug where fb_write returned an
errno code instead of the number of written bytes. See the commit
message of commit 921b7383f348 ("fbdev: Return number of bytes
read or written") for more details.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230706151432.20674-7-tzimmermann@suse.de

diff --git a/drivers/video/fbdev/metronomefb.c b/drivers/video/fbdev/metronomefb.c
index 3e1daca..667bef1 100644 (file)
--- a/drivers/video/fbdev/metronomefb.c
+++ b/drivers/video/fbdev/metronomefb.c
@@ -483,86 +483,28 @@ static void metronomefb_dpy_deferred_io(struct fb_info *info, struct list_head *
        metronome_display_cmd(par);
 }
 
-static void metronomefb_fillrect(struct fb_info *info,
-                                  const struct fb_fillrect *rect)
+static void metronomefb_defio_damage_range(struct fb_info *info, off_t off, size_t len)
 {
        struct metronomefb_par *par = info->par;
 
-       sys_fillrect(info, rect);
        metronomefb_dpy_update(par);
 }
 
-static void metronomefb_copyarea(struct fb_info *info,
-                                  const struct fb_copyarea *area)
+static void metronomefb_defio_damage_area(struct fb_info *info, u32 x, u32 y,
+                                         u32 width, u32 height)
 {
        struct metronomefb_par *par = info->par;
 
-       sys_copyarea(info, area);
        metronomefb_dpy_update(par);
 }
 
-static void metronomefb_imageblit(struct fb_info *info,
-                               const struct fb_image *image)
-{
-       struct metronomefb_par *par = info->par;
-
-       sys_imageblit(info, image);
-       metronomefb_dpy_update(par);
-}
-
-/*
- * this is the slow path from userspace. they can seek and write to
- * the fb. it is based on fb_sys_write
- */
-static ssize_t metronomefb_write(struct fb_info *info, const char __user *buf,
-                               size_t count, loff_t *ppos)
-{
-       struct metronomefb_par *par = info->par;
-       unsigned long p = *ppos;
-       void *dst;
-       int err = 0;
-       unsigned long total_size;
-
-       if (!info->screen_buffer)
-               return -ENODEV;
-
-       total_size = info->fix.smem_len;
-
-       if (p > total_size)
-               return -EFBIG;
-
-       if (count > total_size) {
-               err = -EFBIG;
-               count = total_size;
-       }
-
-       if (count + p > total_size) {
-               if (!err)
-                       err = -ENOSPC;
-
-               count = total_size - p;
-       }
-
-       dst = info->screen_buffer + p;
-
-       if (copy_from_user(dst, buf, count))
-               err = -EFAULT;
-
-       if  (!err)
-               *ppos += count;
-
-       metronomefb_dpy_update(par);
-
-       return (err) ? err : count;
-}
+FB_GEN_DEFAULT_DEFERRED_SYS_OPS(metronomefb,
+                               metronomefb_defio_damage_range,
+                               metronomefb_defio_damage_area)
 
 static const struct fb_ops metronomefb_ops = {
-       .owner          = THIS_MODULE,
-       .fb_write       = metronomefb_write,
-       .fb_fillrect    = metronomefb_fillrect,
-       .fb_copyarea    = metronomefb_copyarea,
-       .fb_imageblit   = metronomefb_imageblit,
-       .fb_mmap        = fb_deferred_io_mmap,
+       .owner  = THIS_MODULE,
+       FB_DEFAULT_DEFERRED_OPS(metronomefb),
 };
 
 static struct fb_deferred_io metronomefb_defio = {