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-rw-r--r--arch/s390/include/asm/mmu.h2
-rw-r--r--arch/s390/include/asm/mmu_context.h5
-rw-r--r--arch/s390/include/asm/pgtable.h128
-rw-r--r--arch/s390/include/asm/setup.h3
-rw-r--r--arch/s390/include/asm/tlbflush.h115
-rw-r--r--arch/s390/kernel/early.c2
-rw-r--r--arch/s390/kernel/smp.c6
-rw-r--r--arch/s390/mm/hugetlbpage.c5
-rw-r--r--arch/s390/mm/init.c7
-rw-r--r--arch/s390/mm/pgtable.c4
-rw-r--r--arch/s390/mm/vmem.c2
11 files changed, 213 insertions, 66 deletions
diff --git a/arch/s390/include/asm/mmu.h b/arch/s390/include/asm/mmu.h
index ff132ac64ddd..f77695a82f64 100644
--- a/arch/s390/include/asm/mmu.h
+++ b/arch/s390/include/asm/mmu.h
@@ -1,9 +1,11 @@
#ifndef __MMU_H
#define __MMU_H
+#include <linux/cpumask.h>
#include <linux/errno.h>
typedef struct {
+ cpumask_t cpu_attach_mask;
atomic_t attach_count;
unsigned int flush_mm;
spinlock_t list_lock;
diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h
index 7abf318b1522..71a258839039 100644
--- a/arch/s390/include/asm/mmu_context.h
+++ b/arch/s390/include/asm/mmu_context.h
@@ -15,6 +15,7 @@
static inline int init_new_context(struct task_struct *tsk,
struct mm_struct *mm)
{
+ cpumask_clear(&mm->context.cpu_attach_mask);
atomic_set(&mm->context.attach_count, 0);
mm->context.flush_mm = 0;
mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
@@ -59,6 +60,8 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
if (prev == next)
return;
+ if (MACHINE_HAS_TLB_LC)
+ cpumask_set_cpu(cpu, &next->context.cpu_attach_mask);
if (atomic_inc_return(&next->context.attach_count) >> 16) {
/* Delay update_user_asce until all TLB flushes are done. */
set_tsk_thread_flag(tsk, TIF_TLB_WAIT);
@@ -73,6 +76,8 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
}
atomic_dec(&prev->context.attach_count);
WARN_ON(atomic_read(&prev->context.attach_count) < 0);
+ if (MACHINE_HAS_TLB_LC)
+ cpumask_clear_cpu(cpu, &prev->context.cpu_attach_mask);
}
#define finish_arch_post_lock_switch finish_arch_post_lock_switch
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 1ab75eaacbd4..66d51834f2cb 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -1068,12 +1068,35 @@ static inline void __ptep_ipte(unsigned long address, pte_t *ptep)
: "=m" (*ptep) : "m" (*ptep), "a" (pto), "a" (address));
}
+static inline void __ptep_ipte_local(unsigned long address, pte_t *ptep)
+{
+ unsigned long pto = (unsigned long) ptep;
+
+#ifndef CONFIG_64BIT
+ /* pto in ESA mode must point to the start of the segment table */
+ pto &= 0x7ffffc00;
+#endif
+ /* Invalidation + local TLB flush for the pte */
+ asm volatile(
+ " .insn rrf,0xb2210000,%2,%3,0,1"
+ : "=m" (*ptep) : "m" (*ptep), "a" (pto), "a" (address));
+}
+
static inline void ptep_flush_direct(struct mm_struct *mm,
unsigned long address, pte_t *ptep)
{
+ int active, count;
+
if (pte_val(*ptep) & _PAGE_INVALID)
return;
- __ptep_ipte(address, ptep);
+ active = (mm == current->active_mm) ? 1 : 0;
+ count = atomic_add_return(0x10000, &mm->context.attach_count);
+ if (MACHINE_HAS_TLB_LC && (count & 0xffff) <= active &&
+ cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
+ __ptep_ipte_local(address, ptep);
+ else
+ __ptep_ipte(address, ptep);
+ atomic_sub(0x10000, &mm->context.attach_count);
}
static inline void ptep_flush_lazy(struct mm_struct *mm,
@@ -1382,35 +1405,6 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
#define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
#define pte_unmap(pte) do { } while (0)
-static inline void __pmd_idte(unsigned long address, pmd_t *pmdp)
-{
- unsigned long sto = (unsigned long) pmdp -
- pmd_index(address) * sizeof(pmd_t);
-
- if (!(pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID)) {
- asm volatile(
- " .insn rrf,0xb98e0000,%2,%3,0,0"
- : "=m" (*pmdp)
- : "m" (*pmdp), "a" (sto),
- "a" ((address & HPAGE_MASK))
- : "cc"
- );
- }
-}
-
-static inline void __pmd_csp(pmd_t *pmdp)
-{
- register unsigned long reg2 asm("2") = pmd_val(*pmdp);
- register unsigned long reg3 asm("3") = pmd_val(*pmdp) |
- _SEGMENT_ENTRY_INVALID;
- register unsigned long reg4 asm("4") = ((unsigned long) pmdp) + 5;
-
- asm volatile(
- " csp %1,%3"
- : "=m" (*pmdp)
- : "d" (reg2), "d" (reg3), "d" (reg4), "m" (*pmdp) : "cc");
-}
-
#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE)
static inline unsigned long massage_pgprot_pmd(pgprot_t pgprot)
{
@@ -1479,18 +1473,80 @@ static inline pmd_t pmd_mkwrite(pmd_t pmd)
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLB_PAGE */
+static inline void __pmdp_csp(pmd_t *pmdp)
+{
+ register unsigned long reg2 asm("2") = pmd_val(*pmdp);
+ register unsigned long reg3 asm("3") = pmd_val(*pmdp) |
+ _SEGMENT_ENTRY_INVALID;
+ register unsigned long reg4 asm("4") = ((unsigned long) pmdp) + 5;
+
+ asm volatile(
+ " csp %1,%3"
+ : "=m" (*pmdp)
+ : "d" (reg2), "d" (reg3), "d" (reg4), "m" (*pmdp) : "cc");
+}
+
+static inline void __pmdp_idte(unsigned long address, pmd_t *pmdp)
+{
+ unsigned long sto;
+
+ sto = (unsigned long) pmdp - pmd_index(address) * sizeof(pmd_t);
+ asm volatile(
+ " .insn rrf,0xb98e0000,%2,%3,0,0"
+ : "=m" (*pmdp)
+ : "m" (*pmdp), "a" (sto), "a" ((address & HPAGE_MASK))
+ : "cc" );
+}
+
+static inline void __pmdp_idte_local(unsigned long address, pmd_t *pmdp)
+{
+ unsigned long sto;
+
+ sto = (unsigned long) pmdp - pmd_index(address) * sizeof(pmd_t);
+ asm volatile(
+ " .insn rrf,0xb98e0000,%2,%3,0,1"
+ : "=m" (*pmdp)
+ : "m" (*pmdp), "a" (sto), "a" ((address & HPAGE_MASK))
+ : "cc" );
+}
+
+static inline void pmdp_flush_direct(struct mm_struct *mm,
+ unsigned long address, pmd_t *pmdp)
+{
+ int active, count;
+
+ if (pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID)
+ return;
+ if (!MACHINE_HAS_IDTE) {
+ __pmdp_csp(pmdp);
+ return;
+ }
+ active = (mm == current->active_mm) ? 1 : 0;
+ count = atomic_add_return(0x10000, &mm->context.attach_count);
+ if (MACHINE_HAS_TLB_LC && (count & 0xffff) <= active &&
+ cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
+ __pmdp_idte_local(address, pmdp);
+ else
+ __pmdp_idte(address, pmdp);
+ atomic_sub(0x10000, &mm->context.attach_count);
+}
+
static inline void pmdp_flush_lazy(struct mm_struct *mm,
unsigned long address, pmd_t *pmdp)
{
int active, count;
+ if (pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID)
+ return;
active = (mm == current->active_mm) ? 1 : 0;
count = atomic_add_return(0x10000, &mm->context.attach_count);
if ((count & 0xffff) <= active) {
pmd_val(*pmdp) |= _SEGMENT_ENTRY_INVALID;
mm->context.flush_mm = 1;
- } else
- __pmd_idte(address, pmdp);
+ } else if (MACHINE_HAS_IDTE)
+ __pmdp_idte(address, pmdp);
+ else
+ __pmdp_csp(pmdp);
atomic_sub(0x10000, &mm->context.attach_count);
}
@@ -1543,7 +1599,7 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
pmd_t pmd;
pmd = *pmdp;
- __pmd_idte(address, pmdp);
+ pmdp_flush_direct(vma->vm_mm, address, pmdp);
*pmdp = pmd_mkold(pmd);
return pmd_young(pmd);
}
@@ -1554,7 +1610,7 @@ static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
{
pmd_t pmd = *pmdp;
- __pmd_idte(address, pmdp);
+ pmdp_flush_direct(mm, address, pmdp);
pmd_clear(pmdp);
return pmd;
}
@@ -1570,7 +1626,7 @@ static inline pmd_t pmdp_clear_flush(struct vm_area_struct *vma,
static inline void pmdp_invalidate(struct vm_area_struct *vma,
unsigned long address, pmd_t *pmdp)
{
- __pmd_idte(address, pmdp);
+ pmdp_flush_direct(vma->vm_mm, address, pmdp);
}
#define __HAVE_ARCH_PMDP_SET_WRPROTECT
@@ -1580,7 +1636,7 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm,
pmd_t pmd = *pmdp;
if (pmd_write(pmd)) {
- __pmd_idte(address, pmdp);
+ pmdp_flush_direct(mm, address, pmdp);
set_pmd_at(mm, address, pmdp, pmd_wrprotect(pmd));
}
}
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index 406f3a1e63ef..b31b22dba948 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -68,6 +68,7 @@ void create_mem_hole(struct mem_chunk mem_chunk[], unsigned long addr,
#define MACHINE_FLAG_TOPOLOGY (1UL << 14)
#define MACHINE_FLAG_TE (1UL << 15)
#define MACHINE_FLAG_RRBM (1UL << 16)
+#define MACHINE_FLAG_TLB_LC (1UL << 17)
#define MACHINE_IS_VM (S390_lowcore.machine_flags & MACHINE_FLAG_VM)
#define MACHINE_IS_KVM (S390_lowcore.machine_flags & MACHINE_FLAG_KVM)
@@ -90,6 +91,7 @@ void create_mem_hole(struct mem_chunk mem_chunk[], unsigned long addr,
#define MACHINE_HAS_TOPOLOGY (0)
#define MACHINE_HAS_TE (0)
#define MACHINE_HAS_RRBM (0)
+#define MACHINE_HAS_TLB_LC (0)
#else /* CONFIG_64BIT */
#define MACHINE_HAS_IEEE (1)
#define MACHINE_HAS_CSP (1)
@@ -102,6 +104,7 @@ void create_mem_hole(struct mem_chunk mem_chunk[], unsigned long addr,
#define MACHINE_HAS_TOPOLOGY (S390_lowcore.machine_flags & MACHINE_FLAG_TOPOLOGY)
#define MACHINE_HAS_TE (S390_lowcore.machine_flags & MACHINE_FLAG_TE)
#define MACHINE_HAS_RRBM (S390_lowcore.machine_flags & MACHINE_FLAG_RRBM)
+#define MACHINE_HAS_TLB_LC (S390_lowcore.machine_flags & MACHINE_FLAG_TLB_LC)
#endif /* CONFIG_64BIT */
/*
diff --git a/arch/s390/include/asm/tlbflush.h b/arch/s390/include/asm/tlbflush.h
index f9fef0425fee..16c9c88658c8 100644
--- a/arch/s390/include/asm/tlbflush.h
+++ b/arch/s390/include/asm/tlbflush.h
@@ -7,19 +7,41 @@
#include <asm/pgalloc.h>
/*
- * Flush all tlb entries on the local cpu.
+ * Flush all TLB entries on the local CPU.
*/
static inline void __tlb_flush_local(void)
{
asm volatile("ptlb" : : : "memory");
}
-#ifdef CONFIG_SMP
/*
- * Flush all tlb entries on all cpus.
+ * Flush TLB entries for a specific ASCE on all CPUs
*/
+static inline void __tlb_flush_idte(unsigned long asce)
+{
+ /* Global TLB flush for the mm */
+ asm volatile(
+ " .insn rrf,0xb98e0000,0,%0,%1,0"
+ : : "a" (2048), "a" (asce) : "cc");
+}
+
+/*
+ * Flush TLB entries for a specific ASCE on the local CPU
+ */
+static inline void __tlb_flush_idte_local(unsigned long asce)
+{
+ /* Local TLB flush for the mm */
+ asm volatile(
+ " .insn rrf,0xb98e0000,0,%0,%1,1"
+ : : "a" (2048), "a" (asce) : "cc");
+}
+
+#ifdef CONFIG_SMP
void smp_ptlb_all(void);
+/*
+ * Flush all TLB entries on all CPUs.
+ */
static inline void __tlb_flush_global(void)
{
register unsigned long reg2 asm("2");
@@ -42,36 +64,89 @@ static inline void __tlb_flush_global(void)
: : "d" (reg2), "d" (reg3), "d" (reg4), "m" (dummy) : "cc" );
}
+/*
+ * Flush TLB entries for a specific mm on all CPUs (in case gmap is used
+ * this implicates multiple ASCEs!).
+ */
static inline void __tlb_flush_full(struct mm_struct *mm)
{
- cpumask_t local_cpumask;
-
preempt_disable();
- /*
- * If the process only ran on the local cpu, do a local flush.
- */
- cpumask_copy(&local_cpumask, cpumask_of(smp_processor_id()));
- if (cpumask_equal(mm_cpumask(mm), &local_cpumask))
+ atomic_add(0x10000, &mm->context.attach_count);
+ if (cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
+ /* Local TLB flush */
__tlb_flush_local();
- else
+ } else {
+ /* Global TLB flush */
__tlb_flush_global();
+ /* Reset TLB flush mask */
+ if (MACHINE_HAS_TLB_LC)
+ cpumask_copy(mm_cpumask(mm),
+ &mm->context.cpu_attach_mask);
+ }
+ atomic_sub(0x10000, &mm->context.attach_count);
preempt_enable();
}
+
+/*
+ * Flush TLB entries for a specific ASCE on all CPUs.
+ */
+static inline void __tlb_flush_asce(struct mm_struct *mm, unsigned long asce)
+{
+ int active, count;
+
+ preempt_disable();
+ active = (mm == current->active_mm) ? 1 : 0;
+ count = atomic_add_return(0x10000, &mm->context.attach_count);
+ if (MACHINE_HAS_TLB_LC && (count & 0xffff) <= active &&
+ cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
+ __tlb_flush_idte_local(asce);
+ } else {
+ if (MACHINE_HAS_IDTE)
+ __tlb_flush_idte(asce);
+ else
+ __tlb_flush_global();
+ /* Reset TLB flush mask */
+ if (MACHINE_HAS_TLB_LC)
+ cpumask_copy(mm_cpumask(mm),
+ &mm->context.cpu_attach_mask);
+ }
+ atomic_sub(0x10000, &mm->context.attach_count);
+ preempt_enable();
+}
+
+static inline void __tlb_flush_kernel(void)
+{
+ if (MACHINE_HAS_IDTE)
+ __tlb_flush_idte((unsigned long) init_mm.pgd |
+ init_mm.context.asce_bits);
+ else
+ __tlb_flush_global();
+}
#else
-#define __tlb_flush_full(mm) __tlb_flush_local()
#define __tlb_flush_global() __tlb_flush_local()
-#endif
+#define __tlb_flush_full(mm) __tlb_flush_local()
/*
- * Flush all tlb entries of a page table on all cpus.
+ * Flush TLB entries for a specific ASCE on all CPUs.
*/
-static inline void __tlb_flush_idte(unsigned long asce)
+static inline void __tlb_flush_asce(struct mm_struct *mm, unsigned long asce)
{
- asm volatile(
- " .insn rrf,0xb98e0000,0,%0,%1,0"
- : : "a" (2048), "a" (asce) : "cc" );
+ if (MACHINE_HAS_TLB_LC)
+ __tlb_flush_idte_local(asce);
+ else
+ __tlb_flush_local();
}
+static inline void __tlb_flush_kernel(void)
+{
+ if (MACHINE_HAS_TLB_LC)
+ __tlb_flush_idte_local((unsigned long) init_mm.pgd |
+ init_mm.context.asce_bits);
+ else
+ __tlb_flush_local();
+}
+#endif
+
static inline void __tlb_flush_mm(struct mm_struct * mm)
{
/*
@@ -80,7 +155,7 @@ static inline void __tlb_flush_mm(struct mm_struct * mm)
* only ran on the local cpu.
*/
if (MACHINE_HAS_IDTE && list_empty(&mm->context.gmap_list))
- __tlb_flush_idte((unsigned long) mm->pgd |
+ __tlb_flush_asce(mm, (unsigned long) mm->pgd |
mm->context.asce_bits);
else
__tlb_flush_full(mm);
@@ -130,7 +205,7 @@ static inline void flush_tlb_range(struct vm_area_struct *vma,
static inline void flush_tlb_kernel_range(unsigned long start,
unsigned long end)
{
- __tlb_flush_mm(&init_mm);
+ __tlb_flush_kernel();
}
#endif /* _S390_TLBFLUSH_H */
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 6b594439cca5..a734f3585ceb 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -386,6 +386,8 @@ static __init void detect_machine_facilities(void)
S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
if (test_facility(66))
S390_lowcore.machine_flags |= MACHINE_FLAG_RRBM;
+ if (test_facility(51))
+ S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
#endif
}
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 366d14460c2b..42a501d13a3b 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -236,6 +236,9 @@ static void pcpu_prepare_secondary(struct pcpu *pcpu, int cpu)
{
struct _lowcore *lc = pcpu->lowcore;
+ if (MACHINE_HAS_TLB_LC)
+ cpumask_set_cpu(cpu, &init_mm.context.cpu_attach_mask);
+ cpumask_set_cpu(cpu, mm_cpumask(&init_mm));
atomic_inc(&init_mm.context.attach_count);
lc->cpu_nr = cpu;
lc->percpu_offset = __per_cpu_offset[cpu];
@@ -760,6 +763,9 @@ void __cpu_die(unsigned int cpu)
cpu_relax();
pcpu_free_lowcore(pcpu);
atomic_dec(&init_mm.context.attach_count);
+ cpumask_clear_cpu(cpu, mm_cpumask(&init_mm));
+ if (MACHINE_HAS_TLB_LC)
+ cpumask_clear_cpu(cpu, &init_mm.context.cpu_attach_mask);
}
void __noreturn cpu_die(void)
diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index d261c62e40a6..0727a55d87d9 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -123,10 +123,7 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
pmd_t *pmdp = (pmd_t *) ptep;
pte_t pte = huge_ptep_get(ptep);
- if (MACHINE_HAS_IDTE)
- __pmd_idte(addr, pmdp);
- else
- __pmd_csp(pmdp);
+ pmdp_flush_direct(mm, addr, pmdp);
pmd_val(*pmdp) = _SEGMENT_ENTRY_EMPTY;
return pte;
}
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index ad446b0c55b6..0c1073ed1e84 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -124,8 +124,6 @@ void __init paging_init(void)
__ctl_load(S390_lowcore.kernel_asce, 13, 13);
arch_local_irq_restore(4UL << (BITS_PER_LONG - 8));
- atomic_set(&init_mm.context.attach_count, 1);
-
sparse_memory_present_with_active_regions(MAX_NUMNODES);
sparse_init();
memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
@@ -136,6 +134,11 @@ void __init paging_init(void)
void __init mem_init(void)
{
+ if (MACHINE_HAS_TLB_LC)
+ cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask);
+ cpumask_set_cpu(0, mm_cpumask(&init_mm));
+ atomic_set(&init_mm.context.attach_count, 1);
+
max_mapnr = max_low_pfn;
high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 24c62900b532..c57c63380184 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -200,7 +200,7 @@ static int gmap_unlink_segment(struct gmap *gmap, unsigned long *table)
static void gmap_flush_tlb(struct gmap *gmap)
{
if (MACHINE_HAS_IDTE)
- __tlb_flush_idte((unsigned long) gmap->table |
+ __tlb_flush_asce(gmap->mm, (unsigned long) gmap->table |
_ASCE_TYPE_REGION1);
else
__tlb_flush_global();
@@ -219,7 +219,7 @@ void gmap_free(struct gmap *gmap)
/* Flush tlb. */
if (MACHINE_HAS_IDTE)
- __tlb_flush_idte((unsigned long) gmap->table |
+ __tlb_flush_asce(gmap->mm, (unsigned long) gmap->table |
_ASCE_TYPE_REGION1);
else
__tlb_flush_global();
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index bcfb70b60be6..72b04de18283 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -138,7 +138,6 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
}
ret = 0;
out:
- flush_tlb_kernel_range(start, end);
return ret;
}
@@ -265,7 +264,6 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
memset((void *)start, 0, end - start);
ret = 0;
out:
- flush_tlb_kernel_range(start, end);
return ret;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-25 21:17:00 +0000