From: Thomas Zimmermann Date: Fri, 28 Apr 2023 12:24:51 +0000 (+0200) Subject: fbdev: Move I/O read and write code into helper functions X-Git-Tag: v6.6.17~3937^2~23^2~338 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6121cd9ef911432b14c2a17aefaf8cd2f3cfcdff;p=platform%2Fkernel%2Flinux-rpi.git fbdev: Move I/O read and write code into helper functions Move the existing I/O read and write code for I/O memory into the new helpers fb_cfb_read() and fb_cfb_write(). Make them the default fp_ops. No functional changes. In the near term, the new functions will be useful to the DRM subsystem, which currently provides it's own implementation. It can then use the shared code. In the longer term, it might make sense to revise the I/O helper's default status and make them opt-in by the driver. Systems that don't use them would not contain the code any longer. v2: * add detailed commit message (Javier) * rename fb_cfb_() to fb_io_() (Geert) * add fixes that got lost while moving the code (Geert) Signed-off-by: Thomas Zimmermann Tested-by: Sui Jingfeng Reviewed-by: Javier Martinez Canillas Acked-by: Helge Deller Reviewed-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20230428122452.4856-19-tzimmermann@suse.de --- diff --git a/drivers/video/fbdev/core/Makefile b/drivers/video/fbdev/core/Makefile index 08fabce..8f00601 100644 --- a/drivers/video/fbdev/core/Makefile +++ b/drivers/video/fbdev/core/Makefile @@ -2,7 +2,7 @@ obj-$(CONFIG_FB_NOTIFY) += fb_notify.o obj-$(CONFIG_FB) += fb.o fb-y := fbmem.o fbmon.o fbcmap.o fbsysfs.o \ - modedb.o fbcvt.o fb_cmdline.o + modedb.o fbcvt.o fb_cmdline.o fb_io_fops.o fb-$(CONFIG_FB_DEFERRED_IO) += fb_defio.o ifeq ($(CONFIG_FRAMEBUFFER_CONSOLE),y) diff --git a/drivers/video/fbdev/core/fb_io_fops.c b/drivers/video/fbdev/core/fb_io_fops.c new file mode 100644 index 0000000..f5299d50 --- /dev/null +++ b/drivers/video/fbdev/core/fb_io_fops.c @@ -0,0 +1,133 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include + +ssize_t fb_io_read(struct fb_info *info, char __user *buf, size_t count, loff_t *ppos) +{ + unsigned long p = *ppos; + u8 *buffer, *dst; + u8 __iomem *src; + int c, cnt = 0, err = 0; + unsigned long total_size, trailing; + + if (!info->screen_base) + return -ENODEV; + + total_size = info->screen_size; + + if (total_size == 0) + total_size = info->fix.smem_len; + + if (p >= total_size) + return 0; + + if (count >= total_size) + count = total_size; + + if (count + p > total_size) + count = total_size - p; + + buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count, + GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + src = (u8 __iomem *) (info->screen_base + p); + + if (info->fbops->fb_sync) + info->fbops->fb_sync(info); + + while (count) { + c = (count > PAGE_SIZE) ? PAGE_SIZE : count; + dst = buffer; + fb_memcpy_fromfb(dst, src, c); + dst += c; + src += c; + + trailing = copy_to_user(buf, buffer, c); + if (trailing == c) { + err = -EFAULT; + break; + } + c -= trailing; + + *ppos += c; + buf += c; + cnt += c; + count -= c; + } + + kfree(buffer); + + return cnt ? cnt : err; +} +EXPORT_SYMBOL(fb_io_read); + +ssize_t fb_io_write(struct fb_info *info, const char __user *buf, size_t count, loff_t *ppos) +{ + unsigned long p = *ppos; + u8 *buffer, *src; + u8 __iomem *dst; + int c, cnt = 0, err = 0; + unsigned long total_size, trailing; + + if (!info->screen_base) + return -ENODEV; + + total_size = info->screen_size; + + if (total_size == 0) + 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; + } + + buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count, + GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + dst = (u8 __iomem *) (info->screen_base + p); + + if (info->fbops->fb_sync) + info->fbops->fb_sync(info); + + while (count) { + c = (count > PAGE_SIZE) ? PAGE_SIZE : count; + src = buffer; + + trailing = copy_from_user(src, buf, c); + if (trailing == c) { + err = -EFAULT; + break; + } + c -= trailing; + + fb_memcpy_tofb(dst, src, c); + dst += c; + src += c; + *ppos += c; + buf += c; + cnt += c; + count -= c; + } + + kfree(buffer); + + return (cnt) ? cnt : err; +} +EXPORT_SYMBOL(fb_io_write); diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index bf5a078..63af408 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -761,12 +761,7 @@ static struct fb_info *file_fb_info(struct file *file) static ssize_t fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { - unsigned long p = *ppos; struct fb_info *info = file_fb_info(file); - u8 *buffer, *dst; - u8 __iomem *src; - int c, cnt = 0, err = 0; - unsigned long total_size, trailing; if (!info) return -ENODEV; @@ -777,67 +772,13 @@ fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) if (info->fbops->fb_read) return info->fbops->fb_read(info, buf, count, ppos); - if (!info->screen_base) - return -ENODEV; - - total_size = info->screen_size; - - if (total_size == 0) - total_size = info->fix.smem_len; - - if (p >= total_size) - return 0; - - if (count >= total_size) - count = total_size; - - if (count + p > total_size) - count = total_size - p; - - buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count, - GFP_KERNEL); - if (!buffer) - return -ENOMEM; - - src = (u8 __iomem *) (info->screen_base + p); - - if (info->fbops->fb_sync) - info->fbops->fb_sync(info); - - while (count) { - c = (count > PAGE_SIZE) ? PAGE_SIZE : count; - dst = buffer; - fb_memcpy_fromfb(dst, src, c); - dst += c; - src += c; - - trailing = copy_to_user(buf, buffer, c); - if (trailing == c) { - err = -EFAULT; - break; - } - c -= trailing; - - *ppos += c; - buf += c; - cnt += c; - count -= c; - } - - kfree(buffer); - - return cnt ? cnt : err; + return fb_io_read(info, buf, count, ppos); } static ssize_t fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - unsigned long p = *ppos; struct fb_info *info = file_fb_info(file); - u8 *buffer, *src; - u8 __iomem *dst; - int c, cnt = 0, err = 0; - unsigned long total_size, trailing; if (!info) return -ENODEV; @@ -848,62 +789,7 @@ fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) if (info->fbops->fb_write) return info->fbops->fb_write(info, buf, count, ppos); - if (!info->screen_base) - return -ENODEV; - - total_size = info->screen_size; - - if (total_size == 0) - 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; - } - - buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count, - GFP_KERNEL); - if (!buffer) - return -ENOMEM; - - dst = (u8 __iomem *) (info->screen_base + p); - - if (info->fbops->fb_sync) - info->fbops->fb_sync(info); - - while (count) { - c = (count > PAGE_SIZE) ? PAGE_SIZE : count; - src = buffer; - - trailing = copy_from_user(src, buf, c); - if (trailing == c) { - err = -EFAULT; - break; - } - c -= trailing; - - fb_memcpy_tofb(dst, src, c); - dst += c; - src += c; - *ppos += c; - buf += c; - cnt += c; - count -= c; - } - - kfree(buffer); - - return (cnt) ? cnt : err; + return fb_io_write(info, buf, count, ppos); } int diff --git a/include/linux/fb.h b/include/linux/fb.h index 08cb47d..ec978a49 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -576,9 +576,19 @@ struct fb_info { extern int fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var); extern int fb_pan_display(struct fb_info *info, struct fb_var_screeninfo *var); extern int fb_blank(struct fb_info *info, int blank); + +/* + * Drawing operations where framebuffer is in I/O memory + */ + extern void cfb_fillrect(struct fb_info *info, const struct fb_fillrect *rect); extern void cfb_copyarea(struct fb_info *info, const struct fb_copyarea *area); extern void cfb_imageblit(struct fb_info *info, const struct fb_image *image); +extern ssize_t fb_io_read(struct fb_info *info, char __user *buf, + size_t count, loff_t *ppos); +extern ssize_t fb_io_write(struct fb_info *info, const char __user *buf, + size_t count, loff_t *ppos); + /* * Drawing operations where framebuffer is in system RAM */