NetBSD/sys/dev/sun/bt_subr.c
chs e07f0b9362 eliminate uvm_useracc() in favor of checking the return value of
copyin() or copyout().

uvm_useracc() tells us whether the mapping permissions allow access to
the desired part of an address space, and many callers assume that
this is the same as knowing whether an attempt to access that part of
the address space will succeed.  however, access to user space can
fail for reasons other than insufficient permission, most notably that
paging in any non-resident data can fail due to i/o errors.  most of
the callers of uvm_useracc() make the above incorrect assumption.  the
rest are all misguided optimizations, which optimize for the case
where an operation will fail.  we'd rather optimize for operations
succeeding, in which case we should just attempt the access and handle
failures due to insufficient permissions the same way we handle i/o
errors.  since there appear to be no good uses of uvm_useracc(), we'll
just remove it.
2003-11-13 03:09:28 +00:00

265 lines
6.4 KiB
C

/* $NetBSD: bt_subr.c,v 1.8 2003/11/13 03:09:29 chs Exp $ */
/*
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratory.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)bt_subr.c 8.2 (Berkeley) 1/21/94
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: bt_subr.c,v 1.8 2003/11/13 03:09:29 chs Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <uvm/uvm_extern.h>
#include <dev/sun/fbio.h>
#include <dev/sun/btreg.h>
#include <dev/sun/btvar.h>
/*
* Common code for dealing with Brooktree video DACs.
* (Contains some software-only code as well, since the colormap
* ioctls are shared between the cgthree and cgsix drivers.)
*/
/*
* Implement an FBIOGETCMAP-like ioctl.
*/
int
bt_getcmap(p, cm, cmsize, uspace)
struct fbcmap *p;
union bt_cmap *cm;
int cmsize;
int uspace;
{
u_int i, start, count;
int error = 0;
u_char *cp, *r, *g, *b;
u_char *cbuf = NULL;
start = p->index;
count = p->count;
if (start >= cmsize || count > cmsize - start)
return (EINVAL);
if (uspace) {
/* Allocate temporary buffer for color values */
cbuf = malloc(3 * count * sizeof(char), M_TEMP, M_WAITOK);
r = cbuf;
g = r + count;
b = g + count;
} else {
/* Direct access in kernel space */
r = p->red;
g = p->green;
b = p->blue;
}
/* Copy colors from BT map to fbcmap */
for (cp = &cm->cm_map[start][0], i = 0; i < count; cp += 3, i++) {
r[i] = cp[0];
g[i] = cp[1];
b[i] = cp[2];
}
if (uspace) {
error = copyout(r, p->red, count);
if (error)
goto out;
error = copyout(g, p->green, count);
if (error)
goto out;
error = copyout(b, p->blue, count);
if (error)
goto out;
}
out:
if (cbuf != NULL)
free(cbuf, M_TEMP);
return (error);
}
/*
* Implement the software portion of an FBIOPUTCMAP-like ioctl.
*/
int
bt_putcmap(p, cm, cmsize, uspace)
struct fbcmap *p;
union bt_cmap *cm;
int cmsize;
int uspace;
{
u_int i, start, count;
int error = 0;
u_char *cp, *r, *g, *b;
u_char *cbuf = NULL;
start = p->index;
count = p->count;
if (start >= cmsize || count > cmsize - start)
return (EINVAL);
if (uspace) {
/* Allocate temporary buffer for color values */
cbuf = malloc(3 * count * sizeof(char), M_TEMP, M_WAITOK);
r = cbuf;
g = r + count;
b = g + count;
error = copyin(p->red, r, count);
if (error)
goto out;
error = copyin(p->green, g, count);
if (error)
goto out;
error = copyin(p->blue, b, count);
if (error)
goto out;
} else {
/* Direct access in kernel space */
r = p->red;
g = p->green;
b = p->blue;
}
/* Copy colors from fbcmap to BT map */
for (cp = &cm->cm_map[start][0], i = 0; i < count; cp += 3, i++) {
cp[0] = r[i];
cp[1] = g[i];
cp[2] = b[i];
}
out:
if (cbuf != NULL)
free(cbuf, M_TEMP);
return (error);
}
/*
* Initialize the color map to the default state:
*
* - 0 is white (PROM uses entry 0 for background)
* - all other entries are black (PROM uses entry 255 for foreground)
*/
void
bt_initcmap(cm, cmsize)
union bt_cmap *cm;
int cmsize;
{
int i;
u_char *cp;
cp = &cm->cm_map[0][0];
cp[0] = cp[1] = cp[2] = 0xff;
for (i = 1, cp = &cm->cm_map[i][0]; i < cmsize; cp += 3, i++)
cp[0] = cp[1] = cp[2] = 0;
#ifdef RASTERCONSOLE
if (cmsize > 16) {
/*
* Setup an ANSI map at offset 1, for rasops;
* see dev/fb.c for usage (XXX - this should
* be replaced by more general colormap handling)
*/
extern u_char rasops_cmap[];
bcopy(rasops_cmap, &cm->cm_map[1][0], 3*16);
}
#endif
}
#if notyet
static void
bt_loadcmap_packed256(fb, bt, start, ncolors)
struct fbdevice *fb;
volatile struct bt_regs *bt;
int start, ncolors;
{
u_int v;
int count, i;
u_char *c[3], **p;
struct cmap *cm = &fb->fb_cmap;
count = BT_D4M3(start + ncolors - 1) - BT_D4M3(start) + 3;
bt = &sc->sc_fbc->fbc_dac;
bt->bt_addr = BT_D4M4(start);
/*
* Figure out where to start in the RGB arrays
* See btreg.h for the way RGB triplets are packed into 4-byte words.
*/
c[0] = &cm->red[(4 * count) / 3)];
c[1] = &cm->green[(4 * count) / 3];
c[2] = &cm->blue[(4 * count) / 3];
p = &c[0];
i = (4 * count) % 3; /* This much of the last triplet is already in
the last packed word */
while (i--) {
c[1-i]++;
p++;
}
while (--count >= 0) {
u_int v = 0;
/*
* Retrieve four colormap entries, pack them into
* a 32-bit word and write to the hardware register.
*/
for (i = 0; i < 4; i++) {
u_char *cp = *p;
v |= *cp++ << (8 * i);
*p = cp;
if (p++ == &c[2])
/* Wrap around */
p = &c[0];
}
bt->bt_cmap = v;
}
}
#endif