[PATCH v2] video: fbdev: fix sys_copyarea
From: Mans Rullgard <hidden>
Date: 2015-01-22 01:20:05
The sys_copyarea() function performs the same operation as
cfb_copyarea() but using normal memory access instead of I/O
accessors. Since the introduction of sys_copyarea(), there
have been two fixes to cfb_copyarea():
- 00a9d699 ("framebuffer: fix cfb_copyarea")
- 5b789da8 ("framebuffer: fix screen corruption when copying")
This patch incorporates the fixes into sys_copyarea() as well.
Signed-off-by: Mans Rullgard <redacted>
---
Changed in v2:
- Fixed wrong first/last calculation in bitcpy_rev()
---
drivers/video/fbdev/core/syscopyarea.c | 137 ++++++++++++++++-----------------
1 file changed, 65 insertions(+), 72 deletions(-)
diff --git a/drivers/video/fbdev/core/syscopyarea.c b/drivers/video/fbdev/core/syscopyarea.c
index 844a32f..c1eda31 100644
--- a/drivers/video/fbdev/core/syscopyarea.c
+++ b/drivers/video/fbdev/core/syscopyarea.c@@ -25,8 +25,8 @@ */ static void -bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx, - const unsigned long *src, int src_idx, int bits, unsigned n) +bitcpy(struct fb_info *p, unsigned long *dst, unsigned dst_idx, + const unsigned long *src, unsigned src_idx, int bits, unsigned n) { unsigned long first, last; int const shift = dst_idx-src_idx;
@@ -86,15 +86,15 @@ bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx, first &= last; if (shift > 0) { /* Single source word */ - *dst = comp(*src >> right, *dst, first); + *dst = comp(*src << left, *dst, first); } else if (src_idx+n <= bits) { /* Single source word */ - *dst = comp(*src << left, *dst, first); + *dst = comp(*src >> right, *dst, first); } else { /* 2 source words */ d0 = *src++; d1 = *src; - *dst = comp(d0 << left | d1 >> right, *dst, + *dst = comp(d0 >> right | d1 << left, *dst, first); } } else {
@@ -109,13 +109,14 @@ bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx, /* Leading bits */ if (shift > 0) { /* Single source word */ - *dst = comp(d0 >> right, *dst, first); + *dst = comp(d0 << left, *dst, first); dst++; n -= bits - dst_idx; } else { /* 2 source words */ d1 = *src++; - *dst = comp(d0 << left | *dst >> right, *dst, first); + *dst = comp(d0 >> right | d1 << left, *dst, + first); d0 = d1; dst++; n -= bits - dst_idx;
@@ -126,36 +127,36 @@ bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx, n /= bits; while (n >= 4) { d1 = *src++; - *dst++ = d0 << left | d1 >> right; + *dst++ = d0 >> right | d1 << left; d0 = d1; d1 = *src++; - *dst++ = d0 << left | d1 >> right; + *dst++ = d0 >> right | d1 << left; d0 = d1; d1 = *src++; - *dst++ = d0 << left | d1 >> right; + *dst++ = d0 >> right | d1 << left; d0 = d1; d1 = *src++; - *dst++ = d0 << left | d1 >> right; + *dst++ = d0 >> right | d1 << left; d0 = d1; n -= 4; } while (n--) { d1 = *src++; - *dst++ = d0 << left | d1 >> right; + *dst++ = d0 >> right | d1 << left; d0 = d1; } /* Trailing bits */ - if (last) { - if (m <= right) { + if (m) { + if (m <= bits - right) { /* Single source word */ - *dst = comp(d0 << left, *dst, last); + d0 >>= right; } else { /* 2 source words */ d1 = *src; - *dst = comp(d0 << left | d1 >> right, - *dst, last); + d0 = d0 >> right | d1 << left; } + *dst = comp(d0, *dst, last); } } }
@@ -166,40 +167,35 @@ bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx, */ static void -bitcpy_rev(struct fb_info *p, unsigned long *dst, int dst_idx, - const unsigned long *src, int src_idx, int bits, unsigned n) +bitcpy_rev(struct fb_info *p, unsigned long *dst, unsigned dst_idx, + const unsigned long *src, unsigned src_idx, unsigned bits, + unsigned n) { unsigned long first, last; int shift; - dst += (n-1)/bits; - src += (n-1)/bits; - if ((n-1) % bits) { - dst_idx += (n-1) % bits; - dst += dst_idx >> (ffs(bits) - 1); - dst_idx &= bits - 1; - src_idx += (n-1) % bits; - src += src_idx >> (ffs(bits) - 1); - src_idx &= bits - 1; - } + dst += (dst_idx + n - 1) / bits; + src += (src_idx + n - 1) / bits; + dst_idx = (dst_idx + n - 1) % bits; + src_idx = (src_idx + n - 1) % bits; shift = dst_idx-src_idx; - first = FB_SHIFT_LOW(p, ~0UL, bits - 1 - dst_idx); - last = ~(FB_SHIFT_LOW(p, ~0UL, bits - 1 - ((dst_idx-n) % bits))); + first = ~FB_SHIFT_HIGH(p, ~0UL, (dst_idx + 1) % bits); + last = FB_SHIFT_HIGH(p, ~0UL, (bits + dst_idx + 1 - n) % bits); if (!shift) { /* Same alignment for source and dest */ if ((unsigned long)dst_idx+1 >= n) { /* Single word */ - if (last) - first &= last; - *dst = comp(*src, *dst, first); + if (first) + last &= first; + *dst = comp(*src, *dst, last); } else { /* Multiple destination words */ /* Leading bits */ - if (first != ~0UL) { + if (first) { *dst = comp(*src, *dst, first); dst--; src--;
@@ -222,29 +218,29 @@ bitcpy_rev(struct fb_info *p, unsigned long *dst, int dst_idx, while (n--) *dst-- = *src--; /* Trailing bits */ - if (last) + if (last != -1UL) *dst = comp(*src, *dst, last); } } else { /* Different alignment for source and dest */ - int const left = -shift & (bits-1); - int const right = shift & (bits-1); + int const left = shift & (bits-1); + int const right = -shift & (bits-1); if ((unsigned long)dst_idx+1 >= n) { /* Single destination word */ - if (last) - first &= last; + if (first) + last &= first; if (shift < 0) { /* Single source word */ - *dst = comp(*src << left, *dst, first); + *dst = comp(*src >> right, *dst, last); } else if (1+(unsigned long)src_idx >= n) { /* Single source word */ - *dst = comp(*src >> right, *dst, first); + *dst = comp(*src << left, *dst, last); } else { /* 2 source words */ - *dst = comp(*src >> right | *(src-1) << left, - *dst, first); + *dst = comp(*src << left | *(src-1) >> right, + *dst, last); } } else { /* Multiple destination words */
@@ -261,14 +257,18 @@ bitcpy_rev(struct fb_info *p, unsigned long *dst, int dst_idx, /* Leading bits */ if (shift < 0) { /* Single source word */ - *dst = comp(d0 << left, *dst, first); + d1 = d0; + d0 >>= right; } else { /* 2 source words */ d1 = *src--; - *dst = comp(d0 >> right | d1 << left, *dst, - first); - d0 = d1; + d0 = d0 << left | d1 >> right; } + if (!first) + *dst = d0; + else + *dst = comp(d0, *dst, first); + d0 = d1; dst--; n -= dst_idx+1;
@@ -277,36 +277,36 @@ bitcpy_rev(struct fb_info *p, unsigned long *dst, int dst_idx, n /= bits; while (n >= 4) { d1 = *src--; - *dst-- = d0 >> right | d1 << left; + *dst-- = d0 << left | d1 >> right; d0 = d1; d1 = *src--; - *dst-- = d0 >> right | d1 << left; + *dst-- = d0 << left | d1 >> right; d0 = d1; d1 = *src--; - *dst-- = d0 >> right | d1 << left; + *dst-- = d0 << left | d1 >> right; d0 = d1; d1 = *src--; - *dst-- = d0 >> right | d1 << left; + *dst-- = d0 << left | d1 >> right; d0 = d1; n -= 4; } while (n--) { d1 = *src--; - *dst-- = d0 >> right | d1 << left; + *dst-- = d0 << left | d1 >> right; d0 = d1; } /* Trailing bits */ - if (last) { - if (m <= left) { + if (m) { + if (m <= bits - left) { /* Single source word */ - *dst = comp(d0 >> right, *dst, last); + d0 <<= left; } else { /* 2 source words */ d1 = *src; - *dst = comp(d0 >> right | d1 << left, - *dst, last); + d0 = d0 << left | d1 >> right; } + *dst = comp(d0, *dst, last); } } }
@@ -317,9 +317,9 @@ void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area) u32 dx = area->dx, dy = area->dy, sx = area->sx, sy = area->sy; u32 height = area->height, width = area->width; unsigned long const bits_per_line = p->fix.line_length*8u; - unsigned long *dst = NULL, *src = NULL; + unsigned long *base = NULL; int bits = BITS_PER_LONG, bytes = bits >> 3; - int dst_idx = 0, src_idx = 0, rev_copy = 0; + unsigned dst_idx = 0, src_idx = 0, rev_copy = 0; if (p->state != FBINFO_STATE_RUNNING) return;
@@ -334,8 +334,7 @@ void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area) /* split the base of the framebuffer into a long-aligned address and the index of the first bit */ - dst = src = (unsigned long *)((unsigned long)p->screen_base & - ~(bytes-1)); + base = (unsigned long *)((unsigned long)p->screen_base & ~(bytes-1)); dst_idx = src_idx = 8*((unsigned long)p->screen_base & (bytes-1)); /* add offset of source and target area */ dst_idx += dy*bits_per_line + dx*p->var.bits_per_pixel;
@@ -348,20 +347,14 @@ void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area) while (height--) { dst_idx -= bits_per_line; src_idx -= bits_per_line; - dst += dst_idx >> (ffs(bits) - 1); - dst_idx &= (bytes - 1); - src += src_idx >> (ffs(bits) - 1); - src_idx &= (bytes - 1); - bitcpy_rev(p, dst, dst_idx, src, src_idx, bits, + bitcpy_rev(p, base + (dst_idx / bits), dst_idx % bits, + base + (src_idx / bits), src_idx % bits, bits, width*p->var.bits_per_pixel); } } else { while (height--) { - dst += dst_idx >> (ffs(bits) - 1); - dst_idx &= (bytes - 1); - src += src_idx >> (ffs(bits) - 1); - src_idx &= (bytes - 1); - bitcpy(p, dst, dst_idx, src, src_idx, bits, + bitcpy(p, base + (dst_idx / bits), dst_idx % bits, + base + (src_idx / bits), src_idx % bits, bits, width*p->var.bits_per_pixel); dst_idx += bits_per_line; src_idx += bits_per_line;
--
2.0.5