diff options
| author | James Hogan <james@albanarts.com> | 2010-10-28 02:33:28 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-28 05:03:08 +0400 |
| commit | f11b478d461b7113eb4603b3914aaf15b7788e87 (patch) | |
| tree | 84e673927a071c64658d8b24ae423de86948b573 /drivers/video/fbmem.c | |
| parent | c9c62dce35e7fc54beebafb071393a0008989e49 (diff) | |
| download | linux-f11b478d461b7113eb4603b3914aaf15b7788e87.tar.xz | |
fbmem: fix fb_read, fb_write unaligned accesses
fb_{read,write} access the framebuffer using lots of fb_{read,write}l's
but don't check that the file position is aligned which can cause problems
on some architectures which do not support unaligned accesses.
Since the operations are essentially memcpy_{from,to}io, new
fb_memcpy_{from,to}fb macros have been defined and these are used instead.
For Sparc, fb_{read,write} macros use sbus_{read,write}, so this defines
new sbus_memcpy_{from,to}io functions the same as memcpy_{from,to}io but
using sbus_{read,write}b instead of {read,write}b.
Signed-off-by: James Hogan <james@albanarts.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/video/fbmem.c')
| -rw-r--r-- | drivers/video/fbmem.c | 46 |
1 files changed, 14 insertions, 32 deletions
diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index a43442341ddd..0e6aa3d96a42 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -697,9 +697,9 @@ fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) struct inode *inode = file->f_path.dentry->d_inode; int fbidx = iminor(inode); struct fb_info *info = registered_fb[fbidx]; - u32 *buffer, *dst; - u32 __iomem *src; - int c, i, cnt = 0, err = 0; + u8 *buffer, *dst; + u8 __iomem *src; + int c, cnt = 0, err = 0; unsigned long total_size; if (!info || ! info->screen_base) @@ -730,7 +730,7 @@ fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) if (!buffer) return -ENOMEM; - src = (u32 __iomem *) (info->screen_base + p); + src = (u8 __iomem *) (info->screen_base + p); if (info->fbops->fb_sync) info->fbops->fb_sync(info); @@ -738,17 +738,9 @@ fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) while (count) { c = (count > PAGE_SIZE) ? PAGE_SIZE : count; dst = buffer; - for (i = c >> 2; i--; ) - *dst++ = fb_readl(src++); - if (c & 3) { - u8 *dst8 = (u8 *) dst; - u8 __iomem *src8 = (u8 __iomem *) src; - - for (i = c & 3; i--;) - *dst8++ = fb_readb(src8++); - - src = (u32 __iomem *) src8; - } + fb_memcpy_fromfb(dst, src, c); + dst += c; + src += c; if (copy_to_user(buf, buffer, c)) { err = -EFAULT; @@ -772,9 +764,9 @@ fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) struct inode *inode = file->f_path.dentry->d_inode; int fbidx = iminor(inode); struct fb_info *info = registered_fb[fbidx]; - u32 *buffer, *src; - u32 __iomem *dst; - int c, i, cnt = 0, err = 0; + u8 *buffer, *src; + u8 __iomem *dst; + int c, cnt = 0, err = 0; unsigned long total_size; if (!info || !info->screen_base) @@ -811,7 +803,7 @@ fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) if (!buffer) return -ENOMEM; - dst = (u32 __iomem *) (info->screen_base + p); + dst = (u8 __iomem *) (info->screen_base + p); if (info->fbops->fb_sync) info->fbops->fb_sync(info); @@ -825,19 +817,9 @@ fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) break; } - for (i = c >> 2; i--; ) - fb_writel(*src++, dst++); - - if (c & 3) { - u8 *src8 = (u8 *) src; - u8 __iomem *dst8 = (u8 __iomem *) dst; - - for (i = c & 3; i--; ) - fb_writeb(*src8++, dst8++); - - dst = (u32 __iomem *) dst8; - } - + fb_memcpy_tofb(dst, src, c); + dst += c; + src += c; *ppos += c; buf += c; cnt += c; |