/* $NetBSD: copyout.c,v 1.10 2022/05/22 11:27:34 andvar Exp $ */
/*-
* Copyright (c) 2010, 2011 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Raytheon BBN Technologies Corp and Defense Advanced Research Projects
* Agency and which was developed by Matt Thomas of 3am Software Foundry.
*
* This material is based upon work supported by the Defense Advanced Research
* Projects Agency and Space and Naval Warfare Systems Center, Pacific, under
* Contract No. N66001-09-C-2073.
* Approved for Public Release, Distribution Unlimited
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#define __UFETCHSTORE_PRIVATE
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: copyout.c,v 1.10 2022/05/22 11:27:34 andvar Exp $");
#include <sys/param.h>
#include <sys/lwp.h>
#include <sys/systm.h>
#include <powerpc/pcb.h>
#include <powerpc/booke/cpuvar.h>
static inline void
copyout_uint8(uint8_t *udaddr, uint8_t data, register_t ds_msr)
{
register_t msr;
__asm volatile(
"mfmsr %[msr]" /* Save MSR */
"\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */
"\n\t" "stb %[data],0(%[udaddr])" /* store user byte */
"\n\t" "mtmsr %[msr]; sync; isync" /* DS off */
: [msr] "=&r" (msr)
: [ds_msr] "r" (ds_msr), [data] "r" (data), [udaddr] "b" (udaddr));
}
static inline void
copyout_uint16(uint16_t *udaddr, uint8_t data, register_t ds_msr)
{
register_t msr;
__asm volatile(
"mfmsr %[msr]" /* Save MSR */
"\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */
"\n\t" "sth %[data],0(%[udaddr])" /* store user half */
"\n\t" "mtmsr %[msr]; sync; isync" /* DS off */
: [msr] "=&r" (msr)
: [ds_msr] "r" (ds_msr), [data] "r" (data), [udaddr] "b" (udaddr));
}
static inline void
copyout_uint32(uint32_t * const udaddr, uint32_t data, register_t ds_msr)
{
register_t msr;
__asm volatile(
"mfmsr %[msr]" /* Save MSR */
"\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */
"\n\t" "stw %[data],0(%[udaddr])" /* store user data */
"\n\t" "mtmsr %[msr]; sync; isync" /* DS off */
: [msr] "=&r" (msr)
: [ds_msr] "r" (ds_msr), [data] "r" (data), [udaddr] "b" (udaddr));
}
#if 0
static inline void
copyout_le32(uint32_t * const udaddr, uint32_t data, register_t ds_msr)
{
register_t msr;
__asm volatile(
"mfmsr %[msr]" /* Save MSR */
"\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */
"\n\t" "stwbrx %[data],0,%[udaddr]" /* store user data */
"\n\t" "mtmsr %[msr]; sync; isync" /* DS off */
: [msr] "=&r" (msr)
: [ds_msr] "r" (ds_msr), [data] "r" (data), [udaddr] "b" (udaddr));
}
static inline void
copyout_le32_with_mask(uint32_t * const udaddr, uint32_t data,
uint32_t mask, register_t ds_msr)
{
register_t msr;
uint32_t tmp;
KASSERT((data & ~mask) == 0);
__asm volatile(
"mfmsr %[msr]" /* Save MSR */
"\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */
"\n\t" "lwbrx %[tmp],0,%[udaddr]" /* fetch user data */
"\n\t" "andc %[tmp],%[tmp],%[mask]" /* mask out new data */
"\n\t" "or %[tmp],%[tmp],%[data]" /* merge new data */
"\n\t" "stwbrx %[tmp],0,%[udaddr]" /* store user data */
"\n\t" "mtmsr %[msr]; sync; isync" /* DS off */
: [msr] "=&r" (msr), [tmp] "=&r" (tmp)
: [ds_msr] "r" (ds_msr), [data] "r" (data),
[mask] "r" (mask), [udaddr] "b" (udaddr));
}
#endif
static inline void
copyout_16uint8s(const uint8_t *ksaddr8, uint8_t *udaddr8, register_t ds_msr)
{
register_t msr;
__asm volatile(
"mfmsr %[msr]" /* Save MSR */
"\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */
"\n\t" "stb %[data0],0(%[udaddr8])" /* store user data */
"\n\t" "stb %[data1],1(%[udaddr8])" /* store user data */
"\n\t" "stb %[data2],2(%[udaddr8])" /* store user data */
"\n\t" "stb %[data3],3(%[udaddr8])" /* store user data */
"\n\t" "stb %[data4],4(%[udaddr8])" /* store user data */
"\n\t" "stb %[data5],5(%[udaddr8])" /* store user data */
"\n\t" "stb %[data6],6(%[udaddr8])" /* store user data */
"\n\t" "stb %[data7],7(%[udaddr8])" /* store user data */
"\n\t" "stb %[data8],8(%[udaddr8])" /* store user data */
"\n\t" "stb %[data9],9(%[udaddr8])" /* store user data */
"\n\t" "stb %[data10],10(%[udaddr8])" /* store user data */
"\n\t" "stb %[data11],11(%[udaddr8])" /* store user data */
"\n\t" "stb %[data12],12(%[udaddr8])" /* store user data */
"\n\t" "stb %[data13],13(%[udaddr8])" /* store user data */
"\n\t" "stb %[data14],14(%[udaddr8])" /* store user data */
"\n\t" "stb %[data15],15(%[udaddr8])" /* store user data */
"\n\t" "mtmsr %[msr]; sync; isync" /* DS off */
: [msr] "=&r" (msr)
: [ds_msr] "r" (ds_msr), [udaddr8] "b" (udaddr8),
[data0] "r" (ksaddr8[0]), [data1] "r" (ksaddr8[1]),
[data2] "r" (ksaddr8[2]), [data3] "r" (ksaddr8[3]),
[data4] "r" (ksaddr8[4]), [data5] "r" (ksaddr8[5]),
[data6] "r" (ksaddr8[6]), [data7] "r" (ksaddr8[7]),
[data8] "r" (ksaddr8[8]), [data9] "r" (ksaddr8[9]),
[data10] "r" (ksaddr8[10]), [data11] "r" (ksaddr8[11]),
[data12] "r" (ksaddr8[12]), [data13] "r" (ksaddr8[13]),
[data14] "r" (ksaddr8[14]), [data15] "r" (ksaddr8[15]));
}
static inline void
copyout_8uint32s(const uint32_t * const ksaddr32, uint32_t * const udaddr32,
const register_t ds_msr, const size_t line_mask)
{
register_t msr;
register_t tmp;
__asm volatile(
"and. %[tmp],%[line_mask],%[udaddr32]"
"\n\t" "mfmsr %[msr]" /* Save MSR */
"\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */
"\n\t" "bne 0,1f"
"\n\t" "dcba 0,%[udaddr32]"
"\n" "1:"
"\n\t" "stw %[data0],0(%[udaddr32])" /* store user data */
"\n\t" "stw %[data1],4(%[udaddr32])" /* store user data */
"\n\t" "stw %[data2],8(%[udaddr32])" /* store user data */
"\n\t" "stw %[data3],12(%[udaddr32])" /* store user data */
"\n\t" "stw %[data4],16(%[udaddr32])" /* store user data */
"\n\t" "stw %[data5],20(%[udaddr32])" /* store user data */
"\n\t" "stw %[data6],24(%[udaddr32])" /* store user data */
"\n\t" "stw %[data7],28(%[udaddr32])" /* store user data */
"\n\t" "mtmsr %[msr]; sync; isync" /* DS off */
: [msr] "=&r" (msr), [tmp] "=&r" (tmp)
: [ds_msr] "r" (ds_msr), [udaddr32] "b" (udaddr32),
[line_mask] "r" (line_mask),
[data0] "r" (ksaddr32[0]), [data1] "r" (ksaddr32[1]),
[data2] "r" (ksaddr32[2]), [data3] "r" (ksaddr32[3]),
[data4] "r" (ksaddr32[4]), [data5] "r" (ksaddr32[5]),
[data6] "r" (ksaddr32[6]), [data7] "r" (ksaddr32[7])
: "cr0");
}
static inline void
copyout_16uint32s(const uint32_t * const ksaddr32, uint32_t * const udaddr32,
const register_t ds_msr, const size_t line_mask)
{
KASSERT(((uintptr_t)udaddr32 & line_mask) == 0);
register_t msr;
register_t tmp;
__asm volatile(
"and. %[tmp],%[line_mask],%[udaddr32]"
"\n\t" "cmplwi 2,%[line_size],32"
"\n\t" "mfmsr %[msr]" /* Save MSR */
"\n\t" "mtmsr %[ds_msr]; sync; isync" /* DS on */
"\n\t" "bne 0,1f"
"\n\t" "dcba 0,%[udaddr32]"
"\n\t" "bne 2,1f"
"\n\t" "dcba %[line_size],%[udaddr32]"
"\n" "1:"
"\n\t" "stw %[data0],0(%[udaddr32])" /* store user data */
"\n\t" "stw %[data1],4(%[udaddr32])" /* store user data */
"\n\t" "stw %[data2],8(%[udaddr32])" /* store user data */
"\n\t" "stw %[data3],12(%[udaddr32])" /* store user data */
"\n\t" "stw %[data4],16(%[udaddr32])" /* store user data */
"\n\t" "stw %[data5],20(%[udaddr32])" /* store user data */
"\n\t" "stw %[data6],24(%[udaddr32])" /* store user data */
"\n\t" "stw %[data7],28(%[udaddr32])" /* store user data */
"\n\t" "stw %[data8],32(%[udaddr32])" /* store user data */
"\n\t" "stw %[data9],36(%[udaddr32])" /* store user data */
"\n\t" "stw %[data10],40(%[udaddr32])" /* store user data */
"\n\t" "stw %[data11],44(%[udaddr32])" /* store user data */
"\n\t" "stw %[data12],48(%[udaddr32])" /* store user data */
"\n\t" "stw %[data13],52(%[udaddr32])" /* store user data */
"\n\t" "stw %[data14],56(%[udaddr32])" /* store user data */
"\n\t" "stw %[data15],60(%[udaddr32])" /* store user data */
"\n\t" "mtmsr %[msr]; sync; isync" /* DS off */
: [msr] "=&r" (msr), [tmp] "=&r" (tmp)
: [ds_msr] "r" (ds_msr), [udaddr32] "b" (udaddr32),
[line_size] "r" (line_mask + 1), [line_mask] "r" (line_mask),
[data0] "r" (ksaddr32[0]), [data1] "r" (ksaddr32[1]),
[data2] "r" (ksaddr32[2]), [data3] "r" (ksaddr32[3]),
[data4] "r" (ksaddr32[4]), [data5] "r" (ksaddr32[5]),
[data6] "r" (ksaddr32[6]), [data7] "r" (ksaddr32[7]),
[data8] "r" (ksaddr32[8]), [data9] "r" (ksaddr32[9]),
[data10] "r" (ksaddr32[10]), [data11] "r" (ksaddr32[11]),
[data12] "r" (ksaddr32[12]), [data13] "r" (ksaddr32[13]),
[data14] "r" (ksaddr32[14]), [data15] "r" (ksaddr32[15])
: "cr0", "cr2");
}
static inline void
copyout_uint8s(vaddr_t ksaddr, vaddr_t udaddr, size_t len, register_t ds_msr)
{
const uint8_t *ksaddr8 = (void *)ksaddr;
uint8_t *udaddr8 = (void *)udaddr;
__builtin_prefetch(ksaddr8, 0, 1);
for (; len >= 16; len -= 16, ksaddr8 += 16, udaddr8 += 16) {
__builtin_prefetch(ksaddr8 + 16, 0, 1);
copyout_16uint8s(ksaddr8, udaddr8, ds_msr);
}
while (len-- > 0) {
copyout_uint8(udaddr8++, *ksaddr8++, ds_msr);
}
}
static inline void
copyout_uint32s(vaddr_t ksaddr, vaddr_t udaddr, size_t len, register_t ds_msr)
{
const size_t line_size = curcpu()->ci_ci.dcache_line_size;
const size_t line_mask = line_size - 1;
const size_t udalignment = udaddr & line_mask;
KASSERT((ksaddr & 3) == 0);
KASSERT((udaddr & 3) == 0);
const uint32_t *ksaddr32 = (void *)ksaddr;
uint32_t *udaddr32 = (void *)udaddr;
len >>= 2;
__builtin_prefetch(ksaddr32, 0, 1);
if (udalignment != 0 && udalignment + 4*len > line_size) {
size_t slen = (line_size - udalignment) >> 2;
len -= slen;
for (; slen >= 8; ksaddr32 += 8, udaddr32 += 8, slen -= 8) {
copyout_8uint32s(ksaddr32, udaddr32, ds_msr, line_mask);
}
while (slen-- > 0) {
copyout_uint32(udaddr32++, *ksaddr32++, ds_msr);
}
if (len == 0)
return;
}
__builtin_prefetch(ksaddr32, 0, 1);
while (len >= 16) {
__builtin_prefetch(ksaddr32 + 8, 0, 1);
__builtin_prefetch(ksaddr32 + 16, 0, 1);
copyout_16uint32s(ksaddr32, udaddr32, ds_msr, line_mask);
ksaddr32 += 16, udaddr32 += 16, len -= 16;
}
KASSERT(len <= 16);
if (len >= 8) {
__builtin_prefetch(ksaddr32 + 8, 0, 1);
copyout_8uint32s(ksaddr32, udaddr32, ds_msr, line_mask);
ksaddr32 += 8, udaddr32 += 8, len -= 8;
}
while (len-- > 0) {
copyout_uint32(udaddr32++, *ksaddr32++, ds_msr);
}
}
int
_ustore_8(uint8_t *vusaddr, uint8_t val)
{
struct pcb * const pcb = lwp_getpcb(curlwp);
struct faultbuf env;
if (setfault(&env) != 0) {
pcb->pcb_onfault = NULL;
return EFAULT;
}
copyout_uint8(vusaddr, val, mfmsr() | PSL_DS);
pcb->pcb_onfault = NULL;
return 0;
}
int
_ustore_16(uint16_t *vusaddr, uint16_t val)
{
struct pcb * const pcb = lwp_getpcb(curlwp);
struct faultbuf env;
if (setfault(&env) != 0) {
pcb->pcb_onfault = NULL;
return EFAULT;
}
copyout_uint16(vusaddr, val, mfmsr() | PSL_DS);
pcb->pcb_onfault = NULL;
return 0;
}
int
_ustore_32(uint32_t *vusaddr, uint32_t val)
{
struct pcb * const pcb = lwp_getpcb(curlwp);
struct faultbuf env;
if (setfault(&env) != 0) {
pcb->pcb_onfault = NULL;
return EFAULT;
}
copyout_uint32(vusaddr, val, mfmsr() | PSL_DS);
pcb->pcb_onfault = NULL;
return 0;
}
int
copyout(const void *vksaddr, void *vudaddr, size_t len)
{
struct pcb * const pcb = lwp_getpcb(curlwp);
struct faultbuf env;
vaddr_t udaddr = (vaddr_t) vudaddr;
vaddr_t ksaddr = (vaddr_t) vksaddr;
if (__predict_false(len == 0)) {
return 0;
}
const register_t ds_msr = mfmsr() | PSL_DS;
int rv = setfault(&env);
if (rv != 0) {
pcb->pcb_onfault = NULL;
return rv;
}
if (__predict_false(len < 4)) {
copyout_uint8s(ksaddr, udaddr, len, ds_msr);
pcb->pcb_onfault = NULL;
return 0;
}
const size_t alignment = (udaddr ^ ksaddr) & 3;
if (__predict_true(alignment == 0)) {
size_t slen;
if (__predict_false(ksaddr & 3)) {
slen = 4 - (ksaddr & 3);
copyout_uint8s(ksaddr, udaddr, slen, ds_msr);
udaddr += slen, ksaddr += slen, len -= slen;
}
slen = len & ~3;
if (__predict_true(slen >= 4)) {
copyout_uint32s(ksaddr, udaddr, slen, ds_msr);
udaddr += slen, ksaddr += slen, len -= slen;
}
}
if (len > 0) {
copyout_uint8s(ksaddr, udaddr, len, ds_msr);
}
pcb->pcb_onfault = NULL;
return 0;
}
#if 1
int
copyoutstr(const void *ksaddr, void *udaddr, size_t len, size_t *done)
{
struct pcb * const pcb = lwp_getpcb(curlwp);
struct faultbuf env;
int rv;
if (__predict_false(len == 0)) {
if (done)
*done = 0;
return 0;
}
rv = setfault(&env);
if (rv != 0) {
pcb->pcb_onfault = NULL;
if (done)
*done = 0;
return rv;
}
const register_t ds_msr = mfmsr() | PSL_DS;
const uint8_t *ksaddr8 = ksaddr;
size_t copylen = 0;
uint8_t *udaddr8 = (void *)udaddr;
while (copylen++ < len) {
const uint8_t data = *ksaddr8++;
copyout_uint8(udaddr8++, data, ds_msr);
if (data == 0)
goto out;
}
rv = ENAMETOOLONG;
out:
pcb->pcb_onfault = NULL;
if (done)
*done = copylen;
return rv;
}
#else
/* XXX This version of copyoutstr(9) has never been enabled so far. */
int
copyoutstr(const void *ksaddr, void *udaddr, size_t len, size_t *lenp)
{
struct pcb * const pcb = lwp_getpcb(curlwp);
struct faultbuf env;
if (__predict_false(len == 0)) {
if (lenp)
*lenp = 0;
return 0;
}
if (setfault(&env)) {
pcb->pcb_onfault = NULL;
if (lenp)
*lenp = 0;
return EFAULT;
}
const register_t ds_msr = mfmsr() | PSL_DS;
const uint8_t *ksaddr8 = ksaddr;
size_t copylen = 0;
uint32_t *udaddr32 = (void *)((uintptr_t)udaddr & ~3);
size_t boff = (uintptr_t)udaddr & 3;
bool done = false;
size_t wlen = 0;
size_t data = 0;
/*
* If the destination buffer doesn't start on a 32-bit boundary
* try to partially fill in the first word. If we succeed we can
* finish writing it while preserving the bytes on front.
*/
if (boff > 0) {
KASSERT(len > 0);
do {
data = (data << 8) | *ksaddr8++;
wlen++;
done = ((uint8_t)data == 0 || len == wlen);
} while (!done && boff + wlen < 4);
KASSERT(wlen > 0);
data <<= 8 * boff;
if (!done || boff + wlen == 4) {
uint32_t mask = 0xffffffff << (8 * boff);
copyout_le32_with_mask(udaddr32++, data, mask, ds_msr);
boff = 0;
copylen = wlen;
wlen = 0;
data = 0;
}
}
/*
* Now we get to the heart of the routine. Build up complete words
* if possible. When we have one, write it to the user's address
* space and go for the next. If we ran out of space or we found the
* end of the string, stop building. If we managed to build a complete
* word, just write it and be happy. Otherwise we have to deal with
* the trailing bytes.
*/
KASSERT(done || boff == 0);
KASSERT(done || copylen < len);
while (!done) {
KASSERT(wlen == 0);
KASSERT(copylen < len);
do {
data = (data << 8) | *ksaddr8++;
wlen++;
done = ((uint8_t)data == 0 || copylen + wlen == len);
} while (!done && wlen < 4);
KASSERT(done || wlen == 4);
if (__predict_true(wlen == 4)) {
copyout_le32(udaddr32++, data, ds_msr);
data = 0;
copylen += wlen;
wlen = 0;
KASSERT(copylen < len || done);
}
}
KASSERT(wlen < 3);
if (wlen) {
/*
* Remember even though we are running big-endian we are using
* byte reversed load/stores so we need to deal with things as
* little endian.
*
* wlen=1 boff=0:
* (~(~0 << 8) << 0) -> (~(0xffffff00) << 0) -> 0x000000ff
* wlen=1 boff=1:
* (~(~0 << 8) << 8) -> (~(0xffffff00) << 8) -> 0x0000ff00
* wlen=1 boff=2:
* (~(~0 << 8) << 16) -> (~(0xffffff00) << 16) -> 0x00ff0000
* wlen=1 boff=3:
* (~(~0 << 8) << 24) -> (~(0xffffff00) << 24) -> 0xff000000
* wlen=2 boff=0:
* (~(~0 << 16) << 0) -> (~(0xffff0000) << 0) -> 0x0000ffff
* wlen=2 boff=1:
* (~(~0 << 16) << 8) -> (~(0xffff0000) << 8) -> 0x00ffff00
* wlen=2 boff=2:
* (~(~0 << 16) << 16) -> (~(0xffff0000) << 16) -> 0xffff0000
* wlen=3 boff=0:
* (~(~0 << 24) << 0) -> (~(0xff000000) << 0) -> 0x00ffffff
* wlen=3 boff=1:
* (~(~0 << 24) << 8) -> (~(0xff000000) << 8) -> 0xffffff00
*/
KASSERT(boff + wlen <= 4);
uint32_t mask = (~(~0 << (8 * wlen))) << (8 * boff);
KASSERT(mask != 0xffffffff);
copyout_le32_with_mask(udaddr32, data, mask, ds_msr);
copylen += wlen;
}
pcb->pcb_onfault = NULL;
if (lenp)
*lenp = copylen;
return 0;
}
#endif
