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qemu/hw/s390x/s390-pci-inst.c
Matthew Rosato 4a8d21ba50 s390x/pci: RPCIT second pass when mappings exhausted 
If we encounter a new mapping while the number of available DMA entries
in vfio is 0, we are currently skipping that mapping which is a problem
if we manage to free up DMA space after that within the same RPCIT --
we will return to the guest with CC0 and have not mapped everything
within the specified range.  This issue was uncovered while testing
changes to the s390 linux kernel iommu/dma code, where a different
usage pattern was employed (new mappings start at the end of the
aperture and work back towards the front, making us far more likely
to encounter new mappings before invalidated mappings during a
global refresh).

Fix this by tracking whether any mappings were skipped due to vfio
DMA limit hitting 0; when this occurs, we still continue the range
and unmap/map anything we can - then we must re-run the range again
to pickup anything that was missed.  This must occur in a loop until
all requests are satisfied (success) or we detect that we are still
unable to complete all mappings (return ZPCI_RPCIT_ST_INSUFF_RES).

Link: https://lore.kernel.org/linux-s390/20221019144435.369902-1-schnelle@linux.ibm.com/
Fixes: 37fa32de70 ("s390x/pci: Honor DMA limits set by vfio")
Reported-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Message-Id: <20221028194758.204007-2-mjrosato@linux.ibm.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-11-06 12:27:35 +01:00

1380 lines
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/*
* s390 PCI instructions
*
* Copyright 2014 IBM Corp.
* Author(s): Frank Blaschka <frank.blaschka@de.ibm.com>
* Hong Bo Li <lihbbj@cn.ibm.com>
* Yi Min Zhao <zyimin@cn.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
* directory.
*/
#include "qemu/osdep.h"
#include "exec/memop.h"
#include "exec/memory-internal.h"
#include "qemu/error-report.h"
#include "sysemu/hw_accel.h"
#include "hw/s390x/s390-pci-inst.h"
#include "hw/s390x/s390-pci-bus.h"
#include "hw/s390x/s390-pci-kvm.h"
#include "hw/s390x/s390-pci-vfio.h"
#include "hw/s390x/tod.h"
#ifndef DEBUG_S390PCI_INST
#define DEBUG_S390PCI_INST 0
#endif
#define DPRINTF(fmt, ...) \
do { \
if (DEBUG_S390PCI_INST) { \
fprintf(stderr, "s390pci-inst: " fmt, ## __VA_ARGS__); \
} \
} while (0)
static inline void inc_dma_avail(S390PCIIOMMU *iommu)
{
if (iommu->dma_limit) {
iommu->dma_limit->avail++;
}
}
static inline void dec_dma_avail(S390PCIIOMMU *iommu)
{
if (iommu->dma_limit) {
iommu->dma_limit->avail--;
}
}
static void s390_set_status_code(CPUS390XState *env,
uint8_t r, uint64_t status_code)
{
env->regs[r] &= ~0xff000000ULL;
env->regs[r] |= (status_code & 0xff) << 24;
}
static int list_pci(ClpReqRspListPci *rrb, uint8_t *cc)
{
S390PCIBusDevice *pbdev = NULL;
S390pciState *s = s390_get_phb();
uint32_t res_code, initial_l2, g_l2;
int rc, i;
uint64_t resume_token;
rc = 0;
if (lduw_p(&rrb->request.hdr.len) != 32) {
res_code = CLP_RC_LEN;
rc = -EINVAL;
goto out;
}
if ((ldl_p(&rrb->request.fmt) & CLP_MASK_FMT) != 0) {
res_code = CLP_RC_FMT;
rc = -EINVAL;
goto out;
}
if ((ldl_p(&rrb->request.fmt) & ~CLP_MASK_FMT) != 0 ||
ldq_p(&rrb->request.reserved1) != 0) {
res_code = CLP_RC_RESNOT0;
rc = -EINVAL;
goto out;
}
resume_token = ldq_p(&rrb->request.resume_token);
if (resume_token) {
pbdev = s390_pci_find_dev_by_idx(s, resume_token);
if (!pbdev) {
res_code = CLP_RC_LISTPCI_BADRT;
rc = -EINVAL;
goto out;
}
} else {
pbdev = s390_pci_find_next_avail_dev(s, NULL);
}
if (lduw_p(&rrb->response.hdr.len) < 48) {
res_code = CLP_RC_8K;
rc = -EINVAL;
goto out;
}
initial_l2 = lduw_p(&rrb->response.hdr.len);
if ((initial_l2 - LIST_PCI_HDR_LEN) % sizeof(ClpFhListEntry)
!= 0) {
res_code = CLP_RC_LEN;
rc = -EINVAL;
*cc = 3;
goto out;
}
stl_p(&rrb->response.fmt, 0);
stq_p(&rrb->response.reserved1, 0);
stl_p(&rrb->response.mdd, FH_MASK_SHM);
stw_p(&rrb->response.max_fn, PCI_MAX_FUNCTIONS);
rrb->response.flags = UID_CHECKING_ENABLED;
rrb->response.entry_size = sizeof(ClpFhListEntry);
i = 0;
g_l2 = LIST_PCI_HDR_LEN;
while (g_l2 < initial_l2 && pbdev) {
stw_p(&rrb->response.fh_list[i].device_id,
pci_get_word(pbdev->pdev->config + PCI_DEVICE_ID));
stw_p(&rrb->response.fh_list[i].vendor_id,
pci_get_word(pbdev->pdev->config + PCI_VENDOR_ID));
/* Ignore RESERVED devices. */
stl_p(&rrb->response.fh_list[i].config,
pbdev->state == ZPCI_FS_STANDBY ? 0 : 1 << 31);
stl_p(&rrb->response.fh_list[i].fid, pbdev->fid);
stl_p(&rrb->response.fh_list[i].fh, pbdev->fh);
g_l2 += sizeof(ClpFhListEntry);
/* Add endian check for DPRINTF? */
DPRINTF("g_l2 %d vendor id 0x%x device id 0x%x fid 0x%x fh 0x%x\n",
g_l2,
lduw_p(&rrb->response.fh_list[i].vendor_id),
lduw_p(&rrb->response.fh_list[i].device_id),
ldl_p(&rrb->response.fh_list[i].fid),
ldl_p(&rrb->response.fh_list[i].fh));
pbdev = s390_pci_find_next_avail_dev(s, pbdev);
i++;
}
if (!pbdev) {
resume_token = 0;
} else {
resume_token = pbdev->fh & FH_MASK_INDEX;
}
stq_p(&rrb->response.resume_token, resume_token);
stw_p(&rrb->response.hdr.len, g_l2);
stw_p(&rrb->response.hdr.rsp, CLP_RC_OK);
out:
if (rc) {
DPRINTF("list pci failed rc 0x%x\n", rc);
stw_p(&rrb->response.hdr.rsp, res_code);
}
return rc;
}
int clp_service_call(S390CPU *cpu, uint8_t r2, uintptr_t ra)
{
ClpReqHdr *reqh;
ClpRspHdr *resh;
S390PCIBusDevice *pbdev;
uint32_t req_len;
uint32_t res_len;
uint8_t buffer[4096 * 2];
uint8_t cc = 0;
CPUS390XState *env = &cpu->env;
S390pciState *s = s390_get_phb();
int i;
if (env->psw.mask & PSW_MASK_PSTATE) {
s390_program_interrupt(env, PGM_PRIVILEGED, ra);
return 0;
}
if (s390_cpu_virt_mem_read(cpu, env->regs[r2], r2, buffer, sizeof(*reqh))) {
s390_cpu_virt_mem_handle_exc(cpu, ra);
return 0;
}
reqh = (ClpReqHdr *)buffer;
req_len = lduw_p(&reqh->len);
if (req_len < 16 || req_len > 8184 || (req_len % 8 != 0)) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
if (s390_cpu_virt_mem_read(cpu, env->regs[r2], r2, buffer,
req_len + sizeof(*resh))) {
s390_cpu_virt_mem_handle_exc(cpu, ra);
return 0;
}
resh = (ClpRspHdr *)(buffer + req_len);
res_len = lduw_p(&resh->len);
if (res_len < 8 || res_len > 8176 || (res_len % 8 != 0)) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
if ((req_len + res_len) > 8192) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
if (s390_cpu_virt_mem_read(cpu, env->regs[r2], r2, buffer,
req_len + res_len)) {
s390_cpu_virt_mem_handle_exc(cpu, ra);
return 0;
}
if (req_len != 32) {
stw_p(&resh->rsp, CLP_RC_LEN);
goto out;
}
switch (lduw_p(&reqh->cmd)) {
case CLP_LIST_PCI: {
ClpReqRspListPci *rrb = (ClpReqRspListPci *)buffer;
list_pci(rrb, &cc);
break;
}
case CLP_SET_PCI_FN: {
ClpReqSetPci *reqsetpci = (ClpReqSetPci *)reqh;
ClpRspSetPci *ressetpci = (ClpRspSetPci *)resh;
pbdev = s390_pci_find_dev_by_fh(s, ldl_p(&reqsetpci->fh));
if (!pbdev) {
stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_FH);
goto out;
}
switch (reqsetpci->oc) {
case CLP_SET_ENABLE_PCI_FN:
switch (reqsetpci->ndas) {
case 0:
stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_DMAAS);
goto out;
case 1:
break;
default:
stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_RES);
goto out;
}
if (pbdev->fh & FH_MASK_ENABLE) {
stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_FHOP);
goto out;
}
/*
* Take this opportunity to make sure we still have an accurate
* host fh. It's possible part of the handle changed while the
* device was disabled to the guest (e.g. vfio hot reset for
* ISM during plug)
*/
if (pbdev->interp) {
/* Take this opportunity to make sure we are sync'd with host */
if (!s390_pci_get_host_fh(pbdev, &pbdev->fh) ||
!(pbdev->fh & FH_MASK_ENABLE)) {
stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_FH);
goto out;
}
}
pbdev->fh |= FH_MASK_ENABLE;
pbdev->state = ZPCI_FS_ENABLED;
stl_p(&ressetpci->fh, pbdev->fh);
stw_p(&ressetpci->hdr.rsp, CLP_RC_OK);
break;
case CLP_SET_DISABLE_PCI_FN:
if (!(pbdev->fh & FH_MASK_ENABLE)) {
stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_FHOP);
goto out;
}
device_legacy_reset(DEVICE(pbdev));
pbdev->fh &= ~FH_MASK_ENABLE;
pbdev->state = ZPCI_FS_DISABLED;
stl_p(&ressetpci->fh, pbdev->fh);
stw_p(&ressetpci->hdr.rsp, CLP_RC_OK);
break;
default:
DPRINTF("unknown set pci command\n");
stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_FHOP);
break;
}
break;
}
case CLP_QUERY_PCI_FN: {
ClpReqQueryPci *reqquery = (ClpReqQueryPci *)reqh;
ClpRspQueryPci *resquery = (ClpRspQueryPci *)resh;
pbdev = s390_pci_find_dev_by_fh(s, ldl_p(&reqquery->fh));
if (!pbdev) {
DPRINTF("query pci no pci dev\n");
stw_p(&resquery->hdr.rsp, CLP_RC_SETPCIFN_FH);
goto out;
}
stq_p(&resquery->sdma, pbdev->zpci_fn.sdma);
stq_p(&resquery->edma, pbdev->zpci_fn.edma);
stw_p(&resquery->pchid, pbdev->zpci_fn.pchid);
stw_p(&resquery->vfn, pbdev->zpci_fn.vfn);
resquery->flags = pbdev->zpci_fn.flags;
resquery->pfgid = pbdev->zpci_fn.pfgid;
resquery->pft = pbdev->zpci_fn.pft;
resquery->fmbl = pbdev->zpci_fn.fmbl;
stl_p(&resquery->fid, pbdev->zpci_fn.fid);
stl_p(&resquery->uid, pbdev->zpci_fn.uid);
memcpy(resquery->pfip, pbdev->zpci_fn.pfip, CLP_PFIP_NR_SEGMENTS);
memcpy(resquery->util_str, pbdev->zpci_fn.util_str, CLP_UTIL_STR_LEN);
for (i = 0; i < PCI_BAR_COUNT; i++) {
uint32_t data = pci_get_long(pbdev->pdev->config +
PCI_BASE_ADDRESS_0 + (i * 4));
stl_p(&resquery->bar[i], data);
resquery->bar_size[i] = pbdev->pdev->io_regions[i].size ?
ctz64(pbdev->pdev->io_regions[i].size) : 0;
DPRINTF("bar %d addr 0x%x size 0x%" PRIx64 "barsize 0x%x\n", i,
ldl_p(&resquery->bar[i]),
pbdev->pdev->io_regions[i].size,
resquery->bar_size[i]);
}
stw_p(&resquery->hdr.rsp, CLP_RC_OK);
break;
}
case CLP_QUERY_PCI_FNGRP: {
ClpRspQueryPciGrp *resgrp = (ClpRspQueryPciGrp *)resh;
ClpReqQueryPciGrp *reqgrp = (ClpReqQueryPciGrp *)reqh;
S390PCIGroup *group;
group = s390_group_find(reqgrp->g);
if (!group) {
/* We do not allow access to unknown groups */
/* The group must have been obtained with a vfio device */
stw_p(&resgrp->hdr.rsp, CLP_RC_QUERYPCIFG_PFGID);
goto out;
}
resgrp->fr = group->zpci_group.fr;
stq_p(&resgrp->dasm, group->zpci_group.dasm);
stq_p(&resgrp->msia, group->zpci_group.msia);
stw_p(&resgrp->mui, group->zpci_group.mui);
stw_p(&resgrp->i, group->zpci_group.i);
stw_p(&resgrp->maxstbl, group->zpci_group.maxstbl);
resgrp->version = group->zpci_group.version;
resgrp->dtsm = group->zpci_group.dtsm;
stw_p(&resgrp->hdr.rsp, CLP_RC_OK);
break;
}
default:
DPRINTF("unknown clp command\n");
stw_p(&resh->rsp, CLP_RC_CMD);
break;
}
out:
if (s390_cpu_virt_mem_write(cpu, env->regs[r2], r2, buffer,
req_len + res_len)) {
s390_cpu_virt_mem_handle_exc(cpu, ra);
return 0;
}
setcc(cpu, cc);
return 0;
}
/**
* Swap data contained in s390x big endian registers to little endian
* PCI bars.
*
* @ptr: a pointer to a uint64_t data field
* @len: the length of the valid data, must be 1,2,4 or 8
*/
static int zpci_endian_swap(uint64_t *ptr, uint8_t len)
{
uint64_t data = *ptr;
switch (len) {
case 1:
break;
case 2:
data = bswap16(data);
break;
case 4:
data = bswap32(data);
break;
case 8:
data = bswap64(data);
break;
default:
return -EINVAL;
}
*ptr = data;
return 0;
}
static MemoryRegion *s390_get_subregion(MemoryRegion *mr, uint64_t offset,
uint8_t len)
{
MemoryRegion *subregion;
uint64_t subregion_size;
QTAILQ_FOREACH(subregion, &mr->subregions, subregions_link) {
subregion_size = int128_get64(subregion->size);
if ((offset >= subregion->addr) &&
(offset + len) <= (subregion->addr + subregion_size)) {
mr = subregion;
break;
}
}
return mr;
}
static MemTxResult zpci_read_bar(S390PCIBusDevice *pbdev, uint8_t pcias,
uint64_t offset, uint64_t *data, uint8_t len)
{
MemoryRegion *mr;
mr = pbdev->pdev->io_regions[pcias].memory;
mr = s390_get_subregion(mr, offset, len);
offset -= mr->addr;
return memory_region_dispatch_read(mr, offset, data,
size_memop(len) | MO_BE,
MEMTXATTRS_UNSPECIFIED);
}
int pcilg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2, uintptr_t ra)
{
CPUS390XState *env = &cpu->env;
S390PCIBusDevice *pbdev;
uint64_t offset;
uint64_t data;
MemTxResult result;
uint8_t len;
uint32_t fh;
uint8_t pcias;
if (env->psw.mask & PSW_MASK_PSTATE) {
s390_program_interrupt(env, PGM_PRIVILEGED, ra);
return 0;
}
if (r2 & 0x1) {
s390_program_interrupt(env, PGM_SPECIFICATION, ra);
return 0;
}
fh = env->regs[r2] >> 32;
pcias = (env->regs[r2] >> 16) & 0xf;
len = env->regs[r2] & 0xf;
offset = env->regs[r2 + 1];
if (!(fh & FH_MASK_ENABLE)) {
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
pbdev = s390_pci_find_dev_by_fh(s390_get_phb(), fh);
if (!pbdev) {
DPRINTF("pcilg no pci dev\n");
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
switch (pbdev->state) {
case ZPCI_FS_PERMANENT_ERROR:
case ZPCI_FS_ERROR:
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r2, ZPCI_PCI_ST_BLOCKED);
return 0;
default:
break;
}
switch (pcias) {
case ZPCI_IO_BAR_MIN...ZPCI_IO_BAR_MAX:
if (!len || (len > (8 - (offset & 0x7)))) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
result = zpci_read_bar(pbdev, pcias, offset, &data, len);
if (result != MEMTX_OK) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
break;
case ZPCI_CONFIG_BAR:
if (!len || (len > (4 - (offset & 0x3))) || len == 3) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
data = pci_host_config_read_common(
pbdev->pdev, offset, pci_config_size(pbdev->pdev), len);
if (zpci_endian_swap(&data, len)) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
break;
default:
DPRINTF("pcilg invalid space\n");
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r2, ZPCI_PCI_ST_INVAL_AS);
return 0;
}
pbdev->fmb.counter[ZPCI_FMB_CNT_LD]++;
env->regs[r1] = data;
setcc(cpu, ZPCI_PCI_LS_OK);
return 0;
}
static MemTxResult zpci_write_bar(S390PCIBusDevice *pbdev, uint8_t pcias,
uint64_t offset, uint64_t data, uint8_t len)
{
MemoryRegion *mr;
mr = pbdev->pdev->io_regions[pcias].memory;
mr = s390_get_subregion(mr, offset, len);
offset -= mr->addr;
return memory_region_dispatch_write(mr, offset, data,
size_memop(len) | MO_BE,
MEMTXATTRS_UNSPECIFIED);
}
int pcistg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2, uintptr_t ra)
{
CPUS390XState *env = &cpu->env;
uint64_t offset, data;
S390PCIBusDevice *pbdev;
MemTxResult result;
uint8_t len;
uint32_t fh;
uint8_t pcias;
if (env->psw.mask & PSW_MASK_PSTATE) {
s390_program_interrupt(env, PGM_PRIVILEGED, ra);
return 0;
}
if (r2 & 0x1) {
s390_program_interrupt(env, PGM_SPECIFICATION, ra);
return 0;
}
fh = env->regs[r2] >> 32;
pcias = (env->regs[r2] >> 16) & 0xf;
len = env->regs[r2] & 0xf;
offset = env->regs[r2 + 1];
data = env->regs[r1];
if (!(fh & FH_MASK_ENABLE)) {
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
pbdev = s390_pci_find_dev_by_fh(s390_get_phb(), fh);
if (!pbdev) {
DPRINTF("pcistg no pci dev\n");
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
switch (pbdev->state) {
/* ZPCI_FS_RESERVED, ZPCI_FS_STANDBY and ZPCI_FS_DISABLED
* are already covered by the FH_MASK_ENABLE check above
*/
case ZPCI_FS_PERMANENT_ERROR:
case ZPCI_FS_ERROR:
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r2, ZPCI_PCI_ST_BLOCKED);
return 0;
default:
break;
}
switch (pcias) {
/* A ZPCI PCI card may use any BAR from BAR 0 to BAR 5 */
case ZPCI_IO_BAR_MIN...ZPCI_IO_BAR_MAX:
/* Check length:
* A length of 0 is invalid and length should not cross a double word
*/
if (!len || (len > (8 - (offset & 0x7)))) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
result = zpci_write_bar(pbdev, pcias, offset, data, len);
if (result != MEMTX_OK) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
break;
case ZPCI_CONFIG_BAR:
/* ZPCI uses the pseudo BAR number 15 as configuration space */
/* possible access lengths are 1,2,4 and must not cross a word */
if (!len || (len > (4 - (offset & 0x3))) || len == 3) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
/* len = 1,2,4 so we do not need to test */
zpci_endian_swap(&data, len);
pci_host_config_write_common(pbdev->pdev, offset,
pci_config_size(pbdev->pdev),
data, len);
break;
default:
DPRINTF("pcistg invalid space\n");
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r2, ZPCI_PCI_ST_INVAL_AS);
return 0;
}
pbdev->fmb.counter[ZPCI_FMB_CNT_ST]++;
setcc(cpu, ZPCI_PCI_LS_OK);
return 0;
}
static uint32_t s390_pci_update_iotlb(S390PCIIOMMU *iommu,
S390IOTLBEntry *entry)
{
S390IOTLBEntry *cache = g_hash_table_lookup(iommu->iotlb, &entry->iova);
IOMMUTLBEvent event = {
.type = entry->perm ? IOMMU_NOTIFIER_MAP : IOMMU_NOTIFIER_UNMAP,
.entry = {
.target_as = &address_space_memory,
.iova = entry->iova,
.translated_addr = entry->translated_addr,
.perm = entry->perm,
.addr_mask = ~TARGET_PAGE_MASK,
},
};
if (event.type == IOMMU_NOTIFIER_UNMAP) {
if (!cache) {
goto out;
}
g_hash_table_remove(iommu->iotlb, &entry->iova);
inc_dma_avail(iommu);
} else {
if (cache) {
if (cache->perm == entry->perm &&
cache->translated_addr == entry->translated_addr) {
goto out;
}
event.type = IOMMU_NOTIFIER_UNMAP;
event.entry.perm = IOMMU_NONE;
memory_region_notify_iommu(&iommu->iommu_mr, 0, event);
event.type = IOMMU_NOTIFIER_MAP;
event.entry.perm = entry->perm;
}
cache = g_new(S390IOTLBEntry, 1);
cache->iova = entry->iova;
cache->translated_addr = entry->translated_addr;
cache->len = TARGET_PAGE_SIZE;
cache->perm = entry->perm;
g_hash_table_replace(iommu->iotlb, &cache->iova, cache);
dec_dma_avail(iommu);
}
memory_region_notify_iommu(&iommu->iommu_mr, 0, event);
out:
return iommu->dma_limit ? iommu->dma_limit->avail : 1;
}
int rpcit_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2, uintptr_t ra)
{
CPUS390XState *env = &cpu->env;
uint32_t fh;
uint16_t error = 0;
S390PCIBusDevice *pbdev;
S390PCIIOMMU *iommu;
S390IOTLBEntry entry;
hwaddr start, end, sstart;
uint32_t dma_avail;
bool again;
if (env->psw.mask & PSW_MASK_PSTATE) {
s390_program_interrupt(env, PGM_PRIVILEGED, ra);
return 0;
}
if (r2 & 0x1) {
s390_program_interrupt(env, PGM_SPECIFICATION, ra);
return 0;
}
fh = env->regs[r1] >> 32;
sstart = start = env->regs[r2];
end = start + env->regs[r2 + 1];
pbdev = s390_pci_find_dev_by_fh(s390_get_phb(), fh);
if (!pbdev) {
DPRINTF("rpcit no pci dev\n");
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
switch (pbdev->state) {
case ZPCI_FS_RESERVED:
case ZPCI_FS_STANDBY:
case ZPCI_FS_DISABLED:
case ZPCI_FS_PERMANENT_ERROR:
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
case ZPCI_FS_ERROR:
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r1, ZPCI_MOD_ST_ERROR_RECOVER);
return 0;
default:
break;
}
iommu = pbdev->iommu;
if (iommu->dma_limit) {
dma_avail = iommu->dma_limit->avail;
} else {
dma_avail = 1;
}
if (!iommu->g_iota) {
error = ERR_EVENT_INVALAS;
goto err;
}
if (end < iommu->pba || start > iommu->pal) {
error = ERR_EVENT_OORANGE;
goto err;
}
retry:
start = sstart;
again = false;
while (start < end) {
error = s390_guest_io_table_walk(iommu->g_iota, start, &entry);
if (error) {
break;
}
start += entry.len;
while (entry.iova < start && entry.iova < end) {
if (dma_avail > 0 || entry.perm == IOMMU_NONE) {
dma_avail = s390_pci_update_iotlb(iommu, &entry);
entry.iova += TARGET_PAGE_SIZE;
entry.translated_addr += TARGET_PAGE_SIZE;
} else {
/*
* We are unable to make a new mapping at this time, continue
* on and hopefully free up more space. Then attempt another
* pass.
*/
again = true;
break;
}
}
}
if (again && dma_avail > 0)
goto retry;
err:
if (error) {
pbdev->state = ZPCI_FS_ERROR;
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r1, ZPCI_PCI_ST_FUNC_IN_ERR);
s390_pci_generate_error_event(error, pbdev->fh, pbdev->fid, start, 0);
} else {
pbdev->fmb.counter[ZPCI_FMB_CNT_RPCIT]++;
if (dma_avail > 0) {
setcc(cpu, ZPCI_PCI_LS_OK);
} else {
/* vfio DMA mappings are exhausted, trigger a RPCIT */
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r1, ZPCI_RPCIT_ST_INSUFF_RES);
}
}
return 0;
}
int pcistb_service_call(S390CPU *cpu, uint8_t r1, uint8_t r3, uint64_t gaddr,
uint8_t ar, uintptr_t ra)
{
CPUS390XState *env = &cpu->env;
S390PCIBusDevice *pbdev;
MemoryRegion *mr;
MemTxResult result;
uint64_t offset;
int i;
uint32_t fh;
uint8_t pcias;
uint16_t len;
uint8_t buffer[128];
if (env->psw.mask & PSW_MASK_PSTATE) {
s390_program_interrupt(env, PGM_PRIVILEGED, ra);
return 0;
}
fh = env->regs[r1] >> 32;
pcias = (env->regs[r1] >> 16) & 0xf;
len = env->regs[r1] & 0x1fff;
offset = env->regs[r3];
if (!(fh & FH_MASK_ENABLE)) {
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
pbdev = s390_pci_find_dev_by_fh(s390_get_phb(), fh);
if (!pbdev) {
DPRINTF("pcistb no pci dev fh 0x%x\n", fh);
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
switch (pbdev->state) {
case ZPCI_FS_PERMANENT_ERROR:
case ZPCI_FS_ERROR:
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r1, ZPCI_PCI_ST_BLOCKED);
return 0;
default:
break;
}
if (pcias > ZPCI_IO_BAR_MAX) {
DPRINTF("pcistb invalid space\n");
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r1, ZPCI_PCI_ST_INVAL_AS);
return 0;
}
/* Verify the address, offset and length */
/* offset must be a multiple of 8 */
if (offset % 8) {
goto specification_error;
}
/* Length must be greater than 8, a multiple of 8 */
/* and not greater than maxstbl */
if ((len <= 8) || (len % 8) ||
(len > pbdev->pci_group->zpci_group.maxstbl)) {
goto specification_error;
}
/* Do not cross a 4K-byte boundary */
if (((offset & 0xfff) + len) > 0x1000) {
goto specification_error;
}
/* Guest address must be double word aligned */
if (gaddr & 0x07UL) {
goto specification_error;
}
mr = pbdev->pdev->io_regions[pcias].memory;
mr = s390_get_subregion(mr, offset, len);
offset -= mr->addr;
for (i = 0; i < len; i += 8) {
if (!memory_region_access_valid(mr, offset + i, 8, true,
MEMTXATTRS_UNSPECIFIED)) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
}
if (s390_cpu_virt_mem_read(cpu, gaddr, ar, buffer, len)) {
s390_cpu_virt_mem_handle_exc(cpu, ra);
return 0;
}
for (i = 0; i < len / 8; i++) {
result = memory_region_dispatch_write(mr, offset + i * 8,
ldq_p(buffer + i * 8),
MO_64, MEMTXATTRS_UNSPECIFIED);
if (result != MEMTX_OK) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
}
pbdev->fmb.counter[ZPCI_FMB_CNT_STB]++;
setcc(cpu, ZPCI_PCI_LS_OK);
return 0;
specification_error:
s390_program_interrupt(env, PGM_SPECIFICATION, ra);
return 0;
}
static int reg_irqs(CPUS390XState *env, S390PCIBusDevice *pbdev, ZpciFib fib)
{
int ret, len;
uint8_t isc = FIB_DATA_ISC(ldl_p(&fib.data));
pbdev->routes.adapter.adapter_id = css_get_adapter_id(
CSS_IO_ADAPTER_PCI, isc);
pbdev->summary_ind = get_indicator(ldq_p(&fib.aisb), sizeof(uint64_t));
len = BITS_TO_LONGS(FIB_DATA_NOI(ldl_p(&fib.data))) * sizeof(unsigned long);
pbdev->indicator = get_indicator(ldq_p(&fib.aibv), len);
ret = map_indicator(&pbdev->routes.adapter, pbdev->summary_ind);
if (ret) {
goto out;
}
ret = map_indicator(&pbdev->routes.adapter, pbdev->indicator);
if (ret) {
goto out;
}
pbdev->routes.adapter.summary_addr = ldq_p(&fib.aisb);
pbdev->routes.adapter.summary_offset = FIB_DATA_AISBO(ldl_p(&fib.data));
pbdev->routes.adapter.ind_addr = ldq_p(&fib.aibv);
pbdev->routes.adapter.ind_offset = FIB_DATA_AIBVO(ldl_p(&fib.data));
pbdev->isc = isc;
pbdev->noi = FIB_DATA_NOI(ldl_p(&fib.data));
pbdev->sum = FIB_DATA_SUM(ldl_p(&fib.data));
DPRINTF("reg_irqs adapter id %d\n", pbdev->routes.adapter.adapter_id);
return 0;
out:
release_indicator(&pbdev->routes.adapter, pbdev->summary_ind);
release_indicator(&pbdev->routes.adapter, pbdev->indicator);
pbdev->summary_ind = NULL;
pbdev->indicator = NULL;
return ret;
}
int pci_dereg_irqs(S390PCIBusDevice *pbdev)
{
release_indicator(&pbdev->routes.adapter, pbdev->summary_ind);
release_indicator(&pbdev->routes.adapter, pbdev->indicator);
pbdev->summary_ind = NULL;
pbdev->indicator = NULL;
pbdev->routes.adapter.summary_addr = 0;
pbdev->routes.adapter.summary_offset = 0;
pbdev->routes.adapter.ind_addr = 0;
pbdev->routes.adapter.ind_offset = 0;
pbdev->isc = 0;
pbdev->noi = 0;
pbdev->sum = 0;
DPRINTF("dereg_irqs adapter id %d\n", pbdev->routes.adapter.adapter_id);
return 0;
}
static int reg_ioat(CPUS390XState *env, S390PCIBusDevice *pbdev, ZpciFib fib,
uintptr_t ra)
{
S390PCIIOMMU *iommu = pbdev->iommu;
uint64_t pba = ldq_p(&fib.pba);
uint64_t pal = ldq_p(&fib.pal);
uint64_t g_iota = ldq_p(&fib.iota);
uint8_t dt = (g_iota >> 2) & 0x7;
uint8_t t = (g_iota >> 11) & 0x1;
pba &= ~0xfff;
pal |= 0xfff;
if (pba > pal || pba < pbdev->zpci_fn.sdma || pal > pbdev->zpci_fn.edma) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return -EINVAL;
}
/* currently we only support designation type 1 with translation */
if (!(dt == ZPCI_IOTA_RTTO && t)) {
error_report("unsupported ioat dt %d t %d", dt, t);
s390_program_interrupt(env, PGM_OPERAND, ra);
return -EINVAL;
}
iommu->pba = pba;
iommu->pal = pal;
iommu->g_iota = g_iota;
s390_pci_iommu_enable(iommu);
return 0;
}
void pci_dereg_ioat(S390PCIIOMMU *iommu)
{
s390_pci_iommu_disable(iommu);
iommu->pba = 0;
iommu->pal = 0;
iommu->g_iota = 0;
}
void fmb_timer_free(S390PCIBusDevice *pbdev)
{
if (pbdev->fmb_timer) {
timer_free(pbdev->fmb_timer);
pbdev->fmb_timer = NULL;
}
pbdev->fmb_addr = 0;
memset(&pbdev->fmb, 0, sizeof(ZpciFmb));
}
static int fmb_do_update(S390PCIBusDevice *pbdev, int offset, uint64_t val,
int len)
{
MemTxResult ret;
uint64_t dst = pbdev->fmb_addr + offset;
switch (len) {
case 8:
address_space_stq_be(&address_space_memory, dst, val,
MEMTXATTRS_UNSPECIFIED,
&ret);
break;
case 4:
address_space_stl_be(&address_space_memory, dst, val,
MEMTXATTRS_UNSPECIFIED,
&ret);
break;
case 2:
address_space_stw_be(&address_space_memory, dst, val,
MEMTXATTRS_UNSPECIFIED,
&ret);
break;
case 1:
address_space_stb(&address_space_memory, dst, val,
MEMTXATTRS_UNSPECIFIED,
&ret);
break;
default:
ret = MEMTX_ERROR;
break;
}
if (ret != MEMTX_OK) {
s390_pci_generate_error_event(ERR_EVENT_FMBA, pbdev->fh, pbdev->fid,
pbdev->fmb_addr, 0);
fmb_timer_free(pbdev);
}
return ret;
}
static void fmb_update(void *opaque)
{
S390PCIBusDevice *pbdev = opaque;
int64_t t = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
int i;
/* Update U bit */
pbdev->fmb.last_update *= 2;
pbdev->fmb.last_update |= UPDATE_U_BIT;
if (fmb_do_update(pbdev, offsetof(ZpciFmb, last_update),
pbdev->fmb.last_update,
sizeof(pbdev->fmb.last_update))) {
return;
}
/* Update FMB sample count */
if (fmb_do_update(pbdev, offsetof(ZpciFmb, sample),
pbdev->fmb.sample++,
sizeof(pbdev->fmb.sample))) {
return;
}
/* Update FMB counters */
for (i = 0; i < ZPCI_FMB_CNT_MAX; i++) {
if (fmb_do_update(pbdev, offsetof(ZpciFmb, counter[i]),
pbdev->fmb.counter[i],
sizeof(pbdev->fmb.counter[0]))) {
return;
}
}
/* Clear U bit and update the time */
pbdev->fmb.last_update = time2tod(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
pbdev->fmb.last_update *= 2;
if (fmb_do_update(pbdev, offsetof(ZpciFmb, last_update),
pbdev->fmb.last_update,
sizeof(pbdev->fmb.last_update))) {
return;
}
timer_mod(pbdev->fmb_timer, t + pbdev->pci_group->zpci_group.mui);
}
static int mpcifc_reg_int_interp(S390PCIBusDevice *pbdev, ZpciFib *fib)
{
int rc;
rc = s390_pci_kvm_aif_enable(pbdev, fib, pbdev->forwarding_assist);
if (rc) {
DPRINTF("Failed to enable interrupt forwarding\n");
return rc;
}
return 0;
}
static int mpcifc_dereg_int_interp(S390PCIBusDevice *pbdev, ZpciFib *fib)
{
int rc;
rc = s390_pci_kvm_aif_disable(pbdev);
if (rc) {
DPRINTF("Failed to disable interrupt forwarding\n");
return rc;
}
return 0;
}
int mpcifc_service_call(S390CPU *cpu, uint8_t r1, uint64_t fiba, uint8_t ar,
uintptr_t ra)
{
CPUS390XState *env = &cpu->env;
uint8_t oc, dmaas;
uint32_t fh;
ZpciFib fib;
S390PCIBusDevice *pbdev;
uint64_t cc = ZPCI_PCI_LS_OK;
if (env->psw.mask & PSW_MASK_PSTATE) {
s390_program_interrupt(env, PGM_PRIVILEGED, ra);
return 0;
}
oc = env->regs[r1] & 0xff;
dmaas = (env->regs[r1] >> 16) & 0xff;
fh = env->regs[r1] >> 32;
if (fiba & 0x7) {
s390_program_interrupt(env, PGM_SPECIFICATION, ra);
return 0;
}
pbdev = s390_pci_find_dev_by_fh(s390_get_phb(), fh);
if (!pbdev) {
DPRINTF("mpcifc no pci dev fh 0x%x\n", fh);
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
switch (pbdev->state) {
case ZPCI_FS_RESERVED:
case ZPCI_FS_STANDBY:
case ZPCI_FS_DISABLED:
case ZPCI_FS_PERMANENT_ERROR:
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
default:
break;
}
if (s390_cpu_virt_mem_read(cpu, fiba, ar, (uint8_t *)&fib, sizeof(fib))) {
s390_cpu_virt_mem_handle_exc(cpu, ra);
return 0;
}
if (fib.fmt != 0) {
s390_program_interrupt(env, PGM_OPERAND, ra);
return 0;
}
switch (oc) {
case ZPCI_MOD_FC_REG_INT:
if (pbdev->interp) {
if (mpcifc_reg_int_interp(pbdev, &fib)) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
}
} else if (pbdev->summary_ind) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
} else if (reg_irqs(env, pbdev, fib)) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_RES_NOT_AVAIL);
}
break;
case ZPCI_MOD_FC_DEREG_INT:
if (pbdev->interp) {
if (mpcifc_dereg_int_interp(pbdev, &fib)) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
}
} else if (!pbdev->summary_ind) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
} else {
pci_dereg_irqs(pbdev);
}
break;
case ZPCI_MOD_FC_REG_IOAT:
if (dmaas != 0) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_DMAAS_INVAL);
} else if (pbdev->iommu->enabled) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
} else if (reg_ioat(env, pbdev, fib, ra)) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_INSUF_RES);
}
break;
case ZPCI_MOD_FC_DEREG_IOAT:
if (dmaas != 0) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_DMAAS_INVAL);
} else if (!pbdev->iommu->enabled) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
} else {
pci_dereg_ioat(pbdev->iommu);
}
break;
case ZPCI_MOD_FC_REREG_IOAT:
if (dmaas != 0) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_DMAAS_INVAL);
} else if (!pbdev->iommu->enabled) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
} else {
pci_dereg_ioat(pbdev->iommu);
if (reg_ioat(env, pbdev, fib, ra)) {
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_INSUF_RES);
}
}
break;
case ZPCI_MOD_FC_RESET_ERROR:
switch (pbdev->state) {
case ZPCI_FS_BLOCKED:
case ZPCI_FS_ERROR:
pbdev->state = ZPCI_FS_ENABLED;
break;
default:
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
}
break;
case ZPCI_MOD_FC_RESET_BLOCK:
switch (pbdev->state) {
case ZPCI_FS_ERROR:
pbdev->state = ZPCI_FS_BLOCKED;
break;
default:
cc = ZPCI_PCI_LS_ERR;
s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
}
break;
case ZPCI_MOD_FC_SET_MEASURE: {
uint64_t fmb_addr = ldq_p(&fib.fmb_addr);
if (fmb_addr & FMBK_MASK) {
cc = ZPCI_PCI_LS_ERR;
s390_pci_generate_error_event(ERR_EVENT_FMBPRO, pbdev->fh,
pbdev->fid, fmb_addr, 0);
fmb_timer_free(pbdev);
break;
}
if (!fmb_addr) {
/* Stop updating FMB. */
fmb_timer_free(pbdev);
break;
}
if (!pbdev->fmb_timer) {
pbdev->fmb_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL,
fmb_update, pbdev);
} else if (timer_pending(pbdev->fmb_timer)) {
/* Remove pending timer to update FMB address. */
timer_del(pbdev->fmb_timer);
}
pbdev->fmb_addr = fmb_addr;
timer_mod(pbdev->fmb_timer,
qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) +
pbdev->pci_group->zpci_group.mui);
break;
}
default:
s390_program_interrupt(&cpu->env, PGM_OPERAND, ra);
cc = ZPCI_PCI_LS_ERR;
}
setcc(cpu, cc);
return 0;
}
int stpcifc_service_call(S390CPU *cpu, uint8_t r1, uint64_t fiba, uint8_t ar,
uintptr_t ra)
{
CPUS390XState *env = &cpu->env;
uint8_t dmaas;
uint32_t fh;
ZpciFib fib;
S390PCIBusDevice *pbdev;
uint32_t data;
uint64_t cc = ZPCI_PCI_LS_OK;
if (env->psw.mask & PSW_MASK_PSTATE) {
s390_program_interrupt(env, PGM_PRIVILEGED, ra);
return 0;
}
fh = env->regs[r1] >> 32;
dmaas = (env->regs[r1] >> 16) & 0xff;
if (dmaas) {
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r1, ZPCI_STPCIFC_ST_INVAL_DMAAS);
return 0;
}
if (fiba & 0x7) {
s390_program_interrupt(env, PGM_SPECIFICATION, ra);
return 0;
}
pbdev = s390_pci_find_dev_by_idx(s390_get_phb(), fh & FH_MASK_INDEX);
if (!pbdev) {
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
memset(&fib, 0, sizeof(fib));
switch (pbdev->state) {
case ZPCI_FS_RESERVED:
case ZPCI_FS_STANDBY:
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
case ZPCI_FS_DISABLED:
if (fh & FH_MASK_ENABLE) {
setcc(cpu, ZPCI_PCI_LS_INVAL_HANDLE);
return 0;
}
goto out;
/* BLOCKED bit is set to one coincident with the setting of ERROR bit.
* FH Enabled bit is set to one in states of ENABLED, BLOCKED or ERROR. */
case ZPCI_FS_ERROR:
fib.fc |= 0x20;
/* fallthrough */
case ZPCI_FS_BLOCKED:
fib.fc |= 0x40;
/* fallthrough */
case ZPCI_FS_ENABLED:
fib.fc |= 0x80;
if (pbdev->iommu->enabled) {
fib.fc |= 0x10;
}
if (!(fh & FH_MASK_ENABLE)) {
env->regs[r1] |= 1ULL << 63;
}
break;
case ZPCI_FS_PERMANENT_ERROR:
setcc(cpu, ZPCI_PCI_LS_ERR);
s390_set_status_code(env, r1, ZPCI_STPCIFC_ST_PERM_ERROR);
return 0;
}
stq_p(&fib.pba, pbdev->iommu->pba);
stq_p(&fib.pal, pbdev->iommu->pal);
stq_p(&fib.iota, pbdev->iommu->g_iota);
stq_p(&fib.aibv, pbdev->routes.adapter.ind_addr);
stq_p(&fib.aisb, pbdev->routes.adapter.summary_addr);
stq_p(&fib.fmb_addr, pbdev->fmb_addr);
data = ((uint32_t)pbdev->isc << 28) | ((uint32_t)pbdev->noi << 16) |
((uint32_t)pbdev->routes.adapter.ind_offset << 8) |
((uint32_t)pbdev->sum << 7) | pbdev->routes.adapter.summary_offset;
stl_p(&fib.data, data);
out:
if (s390_cpu_virt_mem_write(cpu, fiba, ar, (uint8_t *)&fib, sizeof(fib))) {
s390_cpu_virt_mem_handle_exc(cpu, ra);
return 0;
}
setcc(cpu, cc);
return 0;
}
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