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qemu/hw/ppc/spapr_hcall.c
David Gibson dffdaf6162 mmu-hash*: Add hash pte load/store helpers 
On real hardware the ppc hash page table is stored in memory; accordingly
our mmu emulation code can read a hash page table in guest memory.  But,
when paravirtualized under PAPR, the real hash page table is in host
memory, accessible to the guest only via hypercalls.  We model this by
also allowing the MMU emulation code to access a specially allocated hash
page table outside the guest's memory image. At present these two options
are implemented with some ugly conditionals at each access point in the mmu
emulation code.  In the implementation of the PAPR hypercalls, we assume
the external hash table.

This patch cleans things up by adding helpers to load and store from the
hash table for both 32-bit and 64-bit hash mmus.  The 64-bit versions
handle both the in-guest-memory and outside guest memory cases.  The 32-bit
versions only handle the in-guest-memory case since no 32-bit systems can
have an external hash table at present.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-03-22 15:28:48 +01:00

740 lines
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#include "sysemu/sysemu.h"
#include "cpu.h"
#include "sysemu/sysemu.h"
#include "helper_regs.h"
#include "hw/spapr.h"
#include "mmu-hash64.h"
static target_ulong compute_tlbie_rb(target_ulong v, target_ulong r,
target_ulong pte_index)
{
target_ulong rb, va_low;
rb = (v & ~0x7fULL) << 16; /* AVA field */
va_low = pte_index >> 3;
if (v & HPTE64_V_SECONDARY) {
va_low = ~va_low;
}
/* xor vsid from AVA */
if (!(v & HPTE64_V_1TB_SEG)) {
va_low ^= v >> 12;
} else {
va_low ^= v >> 24;
}
va_low &= 0x7ff;
if (v & HPTE64_V_LARGE) {
rb |= 1; /* L field */
#if 0 /* Disable that P7 specific bit for now */
if (r & 0xff000) {
/* non-16MB large page, must be 64k */
/* (masks depend on page size) */
rb |= 0x1000; /* page encoding in LP field */
rb |= (va_low & 0x7f) << 16; /* 7b of VA in AVA/LP field */
rb |= (va_low & 0xfe); /* AVAL field */
}
#endif
} else {
/* 4kB page */
rb |= (va_low & 0x7ff) << 12; /* remaining 11b of AVA */
}
rb |= (v >> 54) & 0x300; /* B field */
return rb;
}
static target_ulong h_enter(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
CPUPPCState *env = &cpu->env;
target_ulong flags = args[0];
target_ulong pte_index = args[1];
target_ulong pteh = args[2];
target_ulong ptel = args[3];
target_ulong page_shift = 12;
target_ulong raddr;
target_ulong i;
hwaddr hpte;
/* only handle 4k and 16M pages for now */
if (pteh & HPTE64_V_LARGE) {
#if 0 /* We don't support 64k pages yet */
if ((ptel & 0xf000) == 0x1000) {
/* 64k page */
} else
#endif
if ((ptel & 0xff000) == 0) {
/* 16M page */
page_shift = 24;
/* lowest AVA bit must be 0 for 16M pages */
if (pteh & 0x80) {
return H_PARAMETER;
}
} else {
return H_PARAMETER;
}
}
raddr = (ptel & HPTE64_R_RPN) & ~((1ULL << page_shift) - 1);
if (raddr < spapr->ram_limit) {
/* Regular RAM - should have WIMG=0010 */
if ((ptel & HPTE64_R_WIMG) != HPTE64_R_M) {
return H_PARAMETER;
}
} else {
/* Looks like an IO address */
/* FIXME: What WIMG combinations could be sensible for IO?
* For now we allow WIMG=010x, but are there others? */
/* FIXME: Should we check against registered IO addresses? */
if ((ptel & (HPTE64_R_W | HPTE64_R_I | HPTE64_R_M)) != HPTE64_R_I) {
return H_PARAMETER;
}
}
pteh &= ~0x60ULL;
if ((pte_index * HASH_PTE_SIZE_64) & ~env->htab_mask) {
return H_PARAMETER;
}
if (likely((flags & H_EXACT) == 0)) {
pte_index &= ~7ULL;
hpte = pte_index * HASH_PTE_SIZE_64;
for (i = 0; ; ++i) {
if (i == 8) {
return H_PTEG_FULL;
}
if ((ppc_hash64_load_hpte0(env, hpte) & HPTE64_V_VALID) == 0) {
break;
}
hpte += HASH_PTE_SIZE_64;
}
} else {
i = 0;
hpte = pte_index * HASH_PTE_SIZE_64;
if (ppc_hash64_load_hpte0(env, hpte) & HPTE64_V_VALID) {
return H_PTEG_FULL;
}
}
ppc_hash64_store_hpte1(env, hpte, ptel);
/* eieio(); FIXME: need some sort of barrier for smp? */
ppc_hash64_store_hpte0(env, hpte, pteh);
args[0] = pte_index + i;
return H_SUCCESS;
}
enum {
REMOVE_SUCCESS = 0,
REMOVE_NOT_FOUND = 1,
REMOVE_PARM = 2,
REMOVE_HW = 3,
};
static target_ulong remove_hpte(CPUPPCState *env, target_ulong ptex,
target_ulong avpn,
target_ulong flags,
target_ulong *vp, target_ulong *rp)
{
hwaddr hpte;
target_ulong v, r, rb;
if ((ptex * HASH_PTE_SIZE_64) & ~env->htab_mask) {
return REMOVE_PARM;
}
hpte = ptex * HASH_PTE_SIZE_64;
v = ppc_hash64_load_hpte0(env, hpte);
r = ppc_hash64_load_hpte1(env, hpte);
if ((v & HPTE64_V_VALID) == 0 ||
((flags & H_AVPN) && (v & ~0x7fULL) != avpn) ||
((flags & H_ANDCOND) && (v & avpn) != 0)) {
return REMOVE_NOT_FOUND;
}
*vp = v;
*rp = r;
ppc_hash64_store_hpte0(env, hpte, 0);
rb = compute_tlbie_rb(v, r, ptex);
ppc_tlb_invalidate_one(env, rb);
return REMOVE_SUCCESS;
}
static target_ulong h_remove(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
CPUPPCState *env = &cpu->env;
target_ulong flags = args[0];
target_ulong pte_index = args[1];
target_ulong avpn = args[2];
int ret;
ret = remove_hpte(env, pte_index, avpn, flags,
&args[0], &args[1]);
switch (ret) {
case REMOVE_SUCCESS:
return H_SUCCESS;
case REMOVE_NOT_FOUND:
return H_NOT_FOUND;
case REMOVE_PARM:
return H_PARAMETER;
case REMOVE_HW:
return H_HARDWARE;
}
assert(0);
}
#define H_BULK_REMOVE_TYPE 0xc000000000000000ULL
#define H_BULK_REMOVE_REQUEST 0x4000000000000000ULL
#define H_BULK_REMOVE_RESPONSE 0x8000000000000000ULL
#define H_BULK_REMOVE_END 0xc000000000000000ULL
#define H_BULK_REMOVE_CODE 0x3000000000000000ULL
#define H_BULK_REMOVE_SUCCESS 0x0000000000000000ULL
#define H_BULK_REMOVE_NOT_FOUND 0x1000000000000000ULL
#define H_BULK_REMOVE_PARM 0x2000000000000000ULL
#define H_BULK_REMOVE_HW 0x3000000000000000ULL
#define H_BULK_REMOVE_RC 0x0c00000000000000ULL
#define H_BULK_REMOVE_FLAGS 0x0300000000000000ULL
#define H_BULK_REMOVE_ABSOLUTE 0x0000000000000000ULL
#define H_BULK_REMOVE_ANDCOND 0x0100000000000000ULL
#define H_BULK_REMOVE_AVPN 0x0200000000000000ULL
#define H_BULK_REMOVE_PTEX 0x00ffffffffffffffULL
#define H_BULK_REMOVE_MAX_BATCH 4
static target_ulong h_bulk_remove(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
CPUPPCState *env = &cpu->env;
int i;
for (i = 0; i < H_BULK_REMOVE_MAX_BATCH; i++) {
target_ulong *tsh = &args[i*2];
target_ulong tsl = args[i*2 + 1];
target_ulong v, r, ret;
if ((*tsh & H_BULK_REMOVE_TYPE) == H_BULK_REMOVE_END) {
break;
} else if ((*tsh & H_BULK_REMOVE_TYPE) != H_BULK_REMOVE_REQUEST) {
return H_PARAMETER;
}
*tsh &= H_BULK_REMOVE_PTEX | H_BULK_REMOVE_FLAGS;
*tsh |= H_BULK_REMOVE_RESPONSE;
if ((*tsh & H_BULK_REMOVE_ANDCOND) && (*tsh & H_BULK_REMOVE_AVPN)) {
*tsh |= H_BULK_REMOVE_PARM;
return H_PARAMETER;
}
ret = remove_hpte(env, *tsh & H_BULK_REMOVE_PTEX, tsl,
(*tsh & H_BULK_REMOVE_FLAGS) >> 26,
&v, &r);
*tsh |= ret << 60;
switch (ret) {
case REMOVE_SUCCESS:
*tsh |= (r & (HPTE64_R_C | HPTE64_R_R)) << 43;
break;
case REMOVE_PARM:
return H_PARAMETER;
case REMOVE_HW:
return H_HARDWARE;
}
}
return H_SUCCESS;
}
static target_ulong h_protect(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
CPUPPCState *env = &cpu->env;
target_ulong flags = args[0];
target_ulong pte_index = args[1];
target_ulong avpn = args[2];
hwaddr hpte;
target_ulong v, r, rb;
if ((pte_index * HASH_PTE_SIZE_64) & ~env->htab_mask) {
return H_PARAMETER;
}
hpte = pte_index * HASH_PTE_SIZE_64;
v = ppc_hash64_load_hpte0(env, hpte);
r = ppc_hash64_load_hpte1(env, hpte);
if ((v & HPTE64_V_VALID) == 0 ||
((flags & H_AVPN) && (v & ~0x7fULL) != avpn)) {
return H_NOT_FOUND;
}
r &= ~(HPTE64_R_PP0 | HPTE64_R_PP | HPTE64_R_N |
HPTE64_R_KEY_HI | HPTE64_R_KEY_LO);
r |= (flags << 55) & HPTE64_R_PP0;
r |= (flags << 48) & HPTE64_R_KEY_HI;
r |= flags & (HPTE64_R_PP | HPTE64_R_N | HPTE64_R_KEY_LO);
rb = compute_tlbie_rb(v, r, pte_index);
ppc_hash64_store_hpte0(env, hpte, v & ~HPTE64_V_VALID);
ppc_tlb_invalidate_one(env, rb);
ppc_hash64_store_hpte1(env, hpte, r);
/* Don't need a memory barrier, due to qemu's global lock */
ppc_hash64_store_hpte0(env, hpte, v);
return H_SUCCESS;
}
static target_ulong h_read(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
CPUPPCState *env = &cpu->env;
target_ulong flags = args[0];
target_ulong pte_index = args[1];
uint8_t *hpte;
int i, ridx, n_entries = 1;
if ((pte_index * HASH_PTE_SIZE_64) & ~env->htab_mask) {
return H_PARAMETER;
}
if (flags & H_READ_4) {
/* Clear the two low order bits */
pte_index &= ~(3ULL);
n_entries = 4;
}
hpte = env->external_htab + (pte_index * HASH_PTE_SIZE_64);
for (i = 0, ridx = 0; i < n_entries; i++) {
args[ridx++] = ldq_p(hpte);
args[ridx++] = ldq_p(hpte + (HASH_PTE_SIZE_64/2));
hpte += HASH_PTE_SIZE_64;
}
return H_SUCCESS;
}
static target_ulong h_set_dabr(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
/* FIXME: actually implement this */
return H_HARDWARE;
}
#define FLAGS_REGISTER_VPA 0x0000200000000000ULL
#define FLAGS_REGISTER_DTL 0x0000400000000000ULL
#define FLAGS_REGISTER_SLBSHADOW 0x0000600000000000ULL
#define FLAGS_DEREGISTER_VPA 0x0000a00000000000ULL
#define FLAGS_DEREGISTER_DTL 0x0000c00000000000ULL
#define FLAGS_DEREGISTER_SLBSHADOW 0x0000e00000000000ULL
#define VPA_MIN_SIZE 640
#define VPA_SIZE_OFFSET 0x4
#define VPA_SHARED_PROC_OFFSET 0x9
#define VPA_SHARED_PROC_VAL 0x2
static target_ulong register_vpa(CPUPPCState *env, target_ulong vpa)
{
uint16_t size;
uint8_t tmp;
if (vpa == 0) {
hcall_dprintf("Can't cope with registering a VPA at logical 0\n");
return H_HARDWARE;
}
if (vpa % env->dcache_line_size) {
return H_PARAMETER;
}
/* FIXME: bounds check the address */
size = lduw_be_phys(vpa + 0x4);
if (size < VPA_MIN_SIZE) {
return H_PARAMETER;
}
/* VPA is not allowed to cross a page boundary */
if ((vpa / 4096) != ((vpa + size - 1) / 4096)) {
return H_PARAMETER;
}
env->vpa_addr = vpa;
tmp = ldub_phys(env->vpa_addr + VPA_SHARED_PROC_OFFSET);
tmp |= VPA_SHARED_PROC_VAL;
stb_phys(env->vpa_addr + VPA_SHARED_PROC_OFFSET, tmp);
return H_SUCCESS;
}
static target_ulong deregister_vpa(CPUPPCState *env, target_ulong vpa)
{
if (env->slb_shadow_addr) {
return H_RESOURCE;
}
if (env->dtl_addr) {
return H_RESOURCE;
}
env->vpa_addr = 0;
return H_SUCCESS;
}
static target_ulong register_slb_shadow(CPUPPCState *env, target_ulong addr)
{
uint32_t size;
if (addr == 0) {
hcall_dprintf("Can't cope with SLB shadow at logical 0\n");
return H_HARDWARE;
}
size = ldl_be_phys(addr + 0x4);
if (size < 0x8) {
return H_PARAMETER;
}
if ((addr / 4096) != ((addr + size - 1) / 4096)) {
return H_PARAMETER;
}
if (!env->vpa_addr) {
return H_RESOURCE;
}
env->slb_shadow_addr = addr;
env->slb_shadow_size = size;
return H_SUCCESS;
}
static target_ulong deregister_slb_shadow(CPUPPCState *env, target_ulong addr)
{
env->slb_shadow_addr = 0;
env->slb_shadow_size = 0;
return H_SUCCESS;
}
static target_ulong register_dtl(CPUPPCState *env, target_ulong addr)
{
uint32_t size;
if (addr == 0) {
hcall_dprintf("Can't cope with DTL at logical 0\n");
return H_HARDWARE;
}
size = ldl_be_phys(addr + 0x4);
if (size < 48) {
return H_PARAMETER;
}
if (!env->vpa_addr) {
return H_RESOURCE;
}
env->dtl_addr = addr;
env->dtl_size = size;
return H_SUCCESS;
}
static target_ulong deregister_dtl(CPUPPCState *env, target_ulong addr)
{
env->dtl_addr = 0;
env->dtl_size = 0;
return H_SUCCESS;
}
static target_ulong h_register_vpa(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong flags = args[0];
target_ulong procno = args[1];
target_ulong vpa = args[2];
target_ulong ret = H_PARAMETER;
CPUPPCState *tenv;
CPUState *tcpu;
tcpu = qemu_get_cpu(procno);
if (!tcpu) {
return H_PARAMETER;
}
tenv = tcpu->env_ptr;
switch (flags) {
case FLAGS_REGISTER_VPA:
ret = register_vpa(tenv, vpa);
break;
case FLAGS_DEREGISTER_VPA:
ret = deregister_vpa(tenv, vpa);
break;
case FLAGS_REGISTER_SLBSHADOW:
ret = register_slb_shadow(tenv, vpa);
break;
case FLAGS_DEREGISTER_SLBSHADOW:
ret = deregister_slb_shadow(tenv, vpa);
break;
case FLAGS_REGISTER_DTL:
ret = register_dtl(tenv, vpa);
break;
case FLAGS_DEREGISTER_DTL:
ret = deregister_dtl(tenv, vpa);
break;
}
return ret;
}
static target_ulong h_cede(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
CPUPPCState *env = &cpu->env;
CPUState *cs = CPU(cpu);
env->msr |= (1ULL << MSR_EE);
hreg_compute_hflags(env);
if (!cpu_has_work(cs)) {
cs->halted = 1;
env->exception_index = EXCP_HLT;
cs->exit_request = 1;
}
return H_SUCCESS;
}
static target_ulong h_rtas(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong rtas_r3 = args[0];
uint32_t token = ldl_be_phys(rtas_r3);
uint32_t nargs = ldl_be_phys(rtas_r3 + 4);
uint32_t nret = ldl_be_phys(rtas_r3 + 8);
return spapr_rtas_call(spapr, token, nargs, rtas_r3 + 12,
nret, rtas_r3 + 12 + 4*nargs);
}
static target_ulong h_logical_load(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong size = args[0];
target_ulong addr = args[1];
switch (size) {
case 1:
args[0] = ldub_phys(addr);
return H_SUCCESS;
case 2:
args[0] = lduw_phys(addr);
return H_SUCCESS;
case 4:
args[0] = ldl_phys(addr);
return H_SUCCESS;
case 8:
args[0] = ldq_phys(addr);
return H_SUCCESS;
}
return H_PARAMETER;
}
static target_ulong h_logical_store(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong size = args[0];
target_ulong addr = args[1];
target_ulong val = args[2];
switch (size) {
case 1:
stb_phys(addr, val);
return H_SUCCESS;
case 2:
stw_phys(addr, val);
return H_SUCCESS;
case 4:
stl_phys(addr, val);
return H_SUCCESS;
case 8:
stq_phys(addr, val);
return H_SUCCESS;
}
return H_PARAMETER;
}
static target_ulong h_logical_memop(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong dst = args[0]; /* Destination address */
target_ulong src = args[1]; /* Source address */
target_ulong esize = args[2]; /* Element size (0=1,1=2,2=4,3=8) */
target_ulong count = args[3]; /* Element count */
target_ulong op = args[4]; /* 0 = copy, 1 = invert */
uint64_t tmp;
unsigned int mask = (1 << esize) - 1;
int step = 1 << esize;
if (count > 0x80000000) {
return H_PARAMETER;
}
if ((dst & mask) || (src & mask) || (op > 1)) {
return H_PARAMETER;
}
if (dst >= src && dst < (src + (count << esize))) {
dst = dst + ((count - 1) << esize);
src = src + ((count - 1) << esize);
step = -step;
}
while (count--) {
switch (esize) {
case 0:
tmp = ldub_phys(src);
break;
case 1:
tmp = lduw_phys(src);
break;
case 2:
tmp = ldl_phys(src);
break;
case 3:
tmp = ldq_phys(src);
break;
default:
return H_PARAMETER;
}
if (op == 1) {
tmp = ~tmp;
}
switch (esize) {
case 0:
stb_phys(dst, tmp);
break;
case 1:
stw_phys(dst, tmp);
break;
case 2:
stl_phys(dst, tmp);
break;
case 3:
stq_phys(dst, tmp);
break;
}
dst = dst + step;
src = src + step;
}
return H_SUCCESS;
}
static target_ulong h_logical_icbi(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
/* Nothing to do on emulation, KVM will trap this in the kernel */
return H_SUCCESS;
}
static target_ulong h_logical_dcbf(PowerPCCPU *cpu, sPAPREnvironment *spapr,
target_ulong opcode, target_ulong *args)
{
/* Nothing to do on emulation, KVM will trap this in the kernel */
return H_SUCCESS;
}
static spapr_hcall_fn papr_hypercall_table[(MAX_HCALL_OPCODE / 4) + 1];
static spapr_hcall_fn kvmppc_hypercall_table[KVMPPC_HCALL_MAX - KVMPPC_HCALL_BASE + 1];
void spapr_register_hypercall(target_ulong opcode, spapr_hcall_fn fn)
{
spapr_hcall_fn *slot;
if (opcode <= MAX_HCALL_OPCODE) {
assert((opcode & 0x3) == 0);
slot = &papr_hypercall_table[opcode / 4];
} else {
assert((opcode >= KVMPPC_HCALL_BASE) && (opcode <= KVMPPC_HCALL_MAX));
slot = &kvmppc_hypercall_table[opcode - KVMPPC_HCALL_BASE];
}
assert(!(*slot));
*slot = fn;
}
target_ulong spapr_hypercall(PowerPCCPU *cpu, target_ulong opcode,
target_ulong *args)
{
if ((opcode <= MAX_HCALL_OPCODE)
&& ((opcode & 0x3) == 0)) {
spapr_hcall_fn fn = papr_hypercall_table[opcode / 4];
if (fn) {
return fn(cpu, spapr, opcode, args);
}
} else if ((opcode >= KVMPPC_HCALL_BASE) &&
(opcode <= KVMPPC_HCALL_MAX)) {
spapr_hcall_fn fn = kvmppc_hypercall_table[opcode - KVMPPC_HCALL_BASE];
if (fn) {
return fn(cpu, spapr, opcode, args);
}
}
hcall_dprintf("Unimplemented hcall 0x" TARGET_FMT_lx "\n", opcode);
return H_FUNCTION;
}
static void hypercall_register_types(void)
{
/* hcall-pft */
spapr_register_hypercall(H_ENTER, h_enter);
spapr_register_hypercall(H_REMOVE, h_remove);
spapr_register_hypercall(H_PROTECT, h_protect);
spapr_register_hypercall(H_READ, h_read);
/* hcall-bulk */
spapr_register_hypercall(H_BULK_REMOVE, h_bulk_remove);
/* hcall-dabr */
spapr_register_hypercall(H_SET_DABR, h_set_dabr);
/* hcall-splpar */
spapr_register_hypercall(H_REGISTER_VPA, h_register_vpa);
spapr_register_hypercall(H_CEDE, h_cede);
/* "debugger" hcalls (also used by SLOF). Note: We do -not- differenciate
* here between the "CI" and the "CACHE" variants, they will use whatever
* mapping attributes qemu is using. When using KVM, the kernel will
* enforce the attributes more strongly
*/
spapr_register_hypercall(H_LOGICAL_CI_LOAD, h_logical_load);
spapr_register_hypercall(H_LOGICAL_CI_STORE, h_logical_store);
spapr_register_hypercall(H_LOGICAL_CACHE_LOAD, h_logical_load);
spapr_register_hypercall(H_LOGICAL_CACHE_STORE, h_logical_store);
spapr_register_hypercall(H_LOGICAL_ICBI, h_logical_icbi);
spapr_register_hypercall(H_LOGICAL_DCBF, h_logical_dcbf);
spapr_register_hypercall(KVMPPC_H_LOGICAL_MEMOP, h_logical_memop);
/* qemu/KVM-PPC specific hcalls */
spapr_register_hypercall(KVMPPC_H_RTAS, h_rtas);
}
type_init(hypercall_register_types)
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