qemu-e2k/hw/ppc/spapr_ovec.c

245 lines
6.3 KiB
C

/*
* QEMU SPAPR Architecture Option Vector Helper Functions
*
* Copyright IBM Corp. 2016
*
* Authors:
* Bharata B Rao <bharata@linux.vnet.ibm.com>
* Michael Roth <mdroth@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "hw/ppc/spapr_ovec.h"
#include "migration/vmstate.h"
#include "qemu/bitmap.h"
#include "exec/address-spaces.h"
#include "qemu/error-report.h"
#include "trace.h"
#include <libfdt.h>
#define OV_MAXBYTES 256 /* not including length byte */
#define OV_MAXBITS (OV_MAXBYTES * BITS_PER_BYTE)
/* we *could* work with bitmaps directly, but handling the bitmap privately
* allows us to more safely make assumptions about the bitmap size and
* simplify the calling code somewhat
*/
struct SpaprOptionVector {
unsigned long *bitmap;
int32_t bitmap_size; /* only used for migration */
};
const VMStateDescription vmstate_spapr_ovec = {
.name = "spapr_option_vector",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_BITMAP(bitmap, SpaprOptionVector, 1, bitmap_size),
VMSTATE_END_OF_LIST()
}
};
SpaprOptionVector *spapr_ovec_new(void)
{
SpaprOptionVector *ov;
ov = g_new0(SpaprOptionVector, 1);
ov->bitmap = bitmap_new(OV_MAXBITS);
ov->bitmap_size = OV_MAXBITS;
return ov;
}
SpaprOptionVector *spapr_ovec_clone(SpaprOptionVector *ov_orig)
{
SpaprOptionVector *ov;
g_assert(ov_orig);
ov = spapr_ovec_new();
bitmap_copy(ov->bitmap, ov_orig->bitmap, OV_MAXBITS);
return ov;
}
void spapr_ovec_intersect(SpaprOptionVector *ov,
SpaprOptionVector *ov1,
SpaprOptionVector *ov2)
{
g_assert(ov);
g_assert(ov1);
g_assert(ov2);
bitmap_and(ov->bitmap, ov1->bitmap, ov2->bitmap, OV_MAXBITS);
}
/* returns true if options bits were removed, false otherwise */
bool spapr_ovec_diff(SpaprOptionVector *ov,
SpaprOptionVector *ov_old,
SpaprOptionVector *ov_new)
{
unsigned long *change_mask = bitmap_new(OV_MAXBITS);
unsigned long *removed_bits = bitmap_new(OV_MAXBITS);
bool bits_were_removed = false;
g_assert(ov);
g_assert(ov_old);
g_assert(ov_new);
bitmap_xor(change_mask, ov_old->bitmap, ov_new->bitmap, OV_MAXBITS);
bitmap_and(ov->bitmap, ov_new->bitmap, change_mask, OV_MAXBITS);
bitmap_and(removed_bits, ov_old->bitmap, change_mask, OV_MAXBITS);
if (!bitmap_empty(removed_bits, OV_MAXBITS)) {
bits_were_removed = true;
}
g_free(change_mask);
g_free(removed_bits);
return bits_were_removed;
}
void spapr_ovec_cleanup(SpaprOptionVector *ov)
{
if (ov) {
g_free(ov->bitmap);
g_free(ov);
}
}
void spapr_ovec_set(SpaprOptionVector *ov, long bitnr)
{
g_assert(ov);
g_assert(bitnr < OV_MAXBITS);
set_bit(bitnr, ov->bitmap);
}
void spapr_ovec_clear(SpaprOptionVector *ov, long bitnr)
{
g_assert(ov);
g_assert(bitnr < OV_MAXBITS);
clear_bit(bitnr, ov->bitmap);
}
bool spapr_ovec_test(SpaprOptionVector *ov, long bitnr)
{
g_assert(ov);
g_assert(bitnr < OV_MAXBITS);
return test_bit(bitnr, ov->bitmap) ? true : false;
}
static void guest_byte_to_bitmap(uint8_t entry, unsigned long *bitmap,
long bitmap_offset)
{
int i;
for (i = 0; i < BITS_PER_BYTE; i++) {
if (entry & (1 << (BITS_PER_BYTE - 1 - i))) {
bitmap_set(bitmap, bitmap_offset + i, 1);
}
}
}
static uint8_t guest_byte_from_bitmap(unsigned long *bitmap, long bitmap_offset)
{
uint8_t entry = 0;
int i;
for (i = 0; i < BITS_PER_BYTE; i++) {
if (test_bit(bitmap_offset + i, bitmap)) {
entry |= (1 << (BITS_PER_BYTE - 1 - i));
}
}
return entry;
}
static target_ulong vector_addr(target_ulong table_addr, int vector)
{
uint16_t vector_count, vector_len;
int i;
vector_count = ldub_phys(&address_space_memory, table_addr) + 1;
if (vector > vector_count) {
return 0;
}
table_addr++; /* skip nr option vectors */
for (i = 0; i < vector - 1; i++) {
vector_len = ldub_phys(&address_space_memory, table_addr) + 1;
table_addr += vector_len + 1; /* bit-vector + length byte */
}
return table_addr;
}
SpaprOptionVector *spapr_ovec_parse_vector(target_ulong table_addr, int vector)
{
SpaprOptionVector *ov;
target_ulong addr;
uint16_t vector_len;
int i;
g_assert(table_addr);
g_assert(vector >= 1); /* vector numbering starts at 1 */
addr = vector_addr(table_addr, vector);
if (!addr) {
/* specified vector isn't present */
return NULL;
}
vector_len = ldub_phys(&address_space_memory, addr++) + 1;
g_assert(vector_len <= OV_MAXBYTES);
ov = spapr_ovec_new();
for (i = 0; i < vector_len; i++) {
uint8_t entry = ldub_phys(&address_space_memory, addr + i);
if (entry) {
trace_spapr_ovec_parse_vector(vector, i + 1, vector_len, entry);
guest_byte_to_bitmap(entry, ov->bitmap, i * BITS_PER_BYTE);
}
}
return ov;
}
int spapr_ovec_populate_dt(void *fdt, int fdt_offset,
SpaprOptionVector *ov, const char *name)
{
uint8_t vec[OV_MAXBYTES + 1];
uint16_t vec_len;
unsigned long lastbit;
int i;
g_assert(ov);
lastbit = find_last_bit(ov->bitmap, OV_MAXBITS);
/* if no bits are set, include at least 1 byte of the vector so we can
* still encoded this in the device tree while abiding by the same
* encoding/sizing expected in ibm,client-architecture-support
*/
vec_len = (lastbit == OV_MAXBITS) ? 1 : lastbit / BITS_PER_BYTE + 1;
g_assert(vec_len <= OV_MAXBYTES);
/* guest expects vector len encoded as vec_len - 1, since the length byte
* is assumed and not included, and the first byte of the vector
* is assumed as well
*/
vec[0] = vec_len - 1;
for (i = 1; i < vec_len + 1; i++) {
vec[i] = guest_byte_from_bitmap(ov->bitmap, (i - 1) * BITS_PER_BYTE);
if (vec[i]) {
trace_spapr_ovec_populate_dt(i, vec_len, vec[i]);
}
}
return fdt_setprop(fdt, fdt_offset, name, vec, vec_len + 1);
}