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-rw-r--r--arch/ia64/mm/tlb.c591
1 files changed, 591 insertions, 0 deletions
diff --git a/arch/ia64/mm/tlb.c b/arch/ia64/mm/tlb.c
new file mode 100644
index 0000000000..ca060e7a2a
--- /dev/null
+++ b/arch/ia64/mm/tlb.c
@@ -0,0 +1,591 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * TLB support routines.
+ *
+ * Copyright (C) 1998-2001, 2003 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ *
+ * 08/02/00 A. Mallick <asit.k.mallick@intel.com>
+ * Modified RID allocation for SMP
+ * Goutham Rao <goutham.rao@intel.com>
+ * IPI based ptc implementation and A-step IPI implementation.
+ * Rohit Seth <rohit.seth@intel.com>
+ * Ken Chen <kenneth.w.chen@intel.com>
+ * Christophe de Dinechin <ddd@hp.com>: Avoid ptc.e on memory allocation
+ * Copyright (C) 2007 Intel Corp
+ * Fenghua Yu <fenghua.yu@intel.com>
+ * Add multiple ptc.g/ptc.ga instruction support in global tlb purge.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+#include <linux/memblock.h>
+#include <linux/slab.h>
+
+#include <asm/delay.h>
+#include <asm/mmu_context.h>
+#include <asm/pal.h>
+#include <asm/tlbflush.h>
+#include <asm/dma.h>
+#include <asm/processor.h>
+#include <asm/sal.h>
+#include <asm/tlb.h>
+
+static struct {
+ u64 mask; /* mask of supported purge page-sizes */
+ unsigned long max_bits; /* log2 of largest supported purge page-size */
+} purge;
+
+struct ia64_ctx ia64_ctx = {
+ .lock = __SPIN_LOCK_UNLOCKED(ia64_ctx.lock),
+ .next = 1,
+ .max_ctx = ~0U
+};
+
+DEFINE_PER_CPU(u8, ia64_need_tlb_flush);
+DEFINE_PER_CPU(u8, ia64_tr_num); /*Number of TR slots in current processor*/
+DEFINE_PER_CPU(u8, ia64_tr_used); /*Max Slot number used by kernel*/
+
+struct ia64_tr_entry *ia64_idtrs[NR_CPUS];
+
+/*
+ * Initializes the ia64_ctx.bitmap array based on max_ctx+1.
+ * Called after cpu_init() has setup ia64_ctx.max_ctx based on
+ * maximum RID that is supported by boot CPU.
+ */
+void __init
+mmu_context_init (void)
+{
+ ia64_ctx.bitmap = memblock_alloc((ia64_ctx.max_ctx + 1) >> 3,
+ SMP_CACHE_BYTES);
+ if (!ia64_ctx.bitmap)
+ panic("%s: Failed to allocate %u bytes\n", __func__,
+ (ia64_ctx.max_ctx + 1) >> 3);
+ ia64_ctx.flushmap = memblock_alloc((ia64_ctx.max_ctx + 1) >> 3,
+ SMP_CACHE_BYTES);
+ if (!ia64_ctx.flushmap)
+ panic("%s: Failed to allocate %u bytes\n", __func__,
+ (ia64_ctx.max_ctx + 1) >> 3);
+}
+
+/*
+ * Acquire the ia64_ctx.lock before calling this function!
+ */
+void
+wrap_mmu_context (struct mm_struct *mm)
+{
+ int i, cpu;
+ unsigned long flush_bit;
+
+ for (i=0; i <= ia64_ctx.max_ctx / BITS_PER_LONG; i++) {
+ flush_bit = xchg(&ia64_ctx.flushmap[i], 0);
+ ia64_ctx.bitmap[i] ^= flush_bit;
+ }
+
+ /* use offset at 300 to skip daemons */
+ ia64_ctx.next = find_next_zero_bit(ia64_ctx.bitmap,
+ ia64_ctx.max_ctx, 300);
+ ia64_ctx.limit = find_next_bit(ia64_ctx.bitmap,
+ ia64_ctx.max_ctx, ia64_ctx.next);
+
+ /*
+ * can't call flush_tlb_all() here because of race condition
+ * with O(1) scheduler [EF]
+ */
+ cpu = get_cpu(); /* prevent preemption/migration */
+ for_each_online_cpu(i)
+ if (i != cpu)
+ per_cpu(ia64_need_tlb_flush, i) = 1;
+ put_cpu();
+ local_flush_tlb_all();
+}
+
+/*
+ * Implement "spinaphores" ... like counting semaphores, but they
+ * spin instead of sleeping. If there are ever any other users for
+ * this primitive it can be moved up to a spinaphore.h header.
+ */
+struct spinaphore {
+ unsigned long ticket;
+ unsigned long serve;
+};
+
+static inline void spinaphore_init(struct spinaphore *ss, int val)
+{
+ ss->ticket = 0;
+ ss->serve = val;
+}
+
+static inline void down_spin(struct spinaphore *ss)
+{
+ unsigned long t = ia64_fetchadd(1, &ss->ticket, acq), serve;
+
+ if (time_before(t, ss->serve))
+ return;
+
+ ia64_invala();
+
+ for (;;) {
+ asm volatile ("ld8.c.nc %0=[%1]" : "=r"(serve) : "r"(&ss->serve) : "memory");
+ if (time_before(t, serve))
+ return;
+ cpu_relax();
+ }
+}
+
+static inline void up_spin(struct spinaphore *ss)
+{
+ ia64_fetchadd(1, &ss->serve, rel);
+}
+
+static struct spinaphore ptcg_sem;
+static u16 nptcg = 1;
+static int need_ptcg_sem = 1;
+static int toolatetochangeptcgsem = 0;
+
+/*
+ * Kernel parameter "nptcg=" overrides max number of concurrent global TLB
+ * purges which is reported from either PAL or SAL PALO.
+ *
+ * We don't have sanity checking for nptcg value. It's the user's responsibility
+ * for valid nptcg value on the platform. Otherwise, kernel may hang in some
+ * cases.
+ */
+static int __init
+set_nptcg(char *str)
+{
+ int value = 0;
+
+ get_option(&str, &value);
+ setup_ptcg_sem(value, NPTCG_FROM_KERNEL_PARAMETER);
+
+ return 1;
+}
+
+__setup("nptcg=", set_nptcg);
+
+/*
+ * Maximum number of simultaneous ptc.g purges in the system can
+ * be defined by PAL_VM_SUMMARY (in which case we should take
+ * the smallest value for any cpu in the system) or by the PAL
+ * override table (in which case we should ignore the value from
+ * PAL_VM_SUMMARY).
+ *
+ * Kernel parameter "nptcg=" overrides maximum number of simultaneous ptc.g
+ * purges defined in either PAL_VM_SUMMARY or PAL override table. In this case,
+ * we should ignore the value from either PAL_VM_SUMMARY or PAL override table.
+ *
+ * Complicating the logic here is the fact that num_possible_cpus()
+ * isn't fully setup until we start bringing cpus online.
+ */
+void
+setup_ptcg_sem(int max_purges, int nptcg_from)
+{
+ static int kp_override;
+ static int palo_override;
+ static int firstcpu = 1;
+
+ if (toolatetochangeptcgsem) {
+ if (nptcg_from == NPTCG_FROM_PAL && max_purges == 0)
+ BUG_ON(1 < nptcg);
+ else
+ BUG_ON(max_purges < nptcg);
+ return;
+ }
+
+ if (nptcg_from == NPTCG_FROM_KERNEL_PARAMETER) {
+ kp_override = 1;
+ nptcg = max_purges;
+ goto resetsema;
+ }
+ if (kp_override) {
+ need_ptcg_sem = num_possible_cpus() > nptcg;
+ return;
+ }
+
+ if (nptcg_from == NPTCG_FROM_PALO) {
+ palo_override = 1;
+
+ /* In PALO max_purges == 0 really means it! */
+ if (max_purges == 0)
+ panic("Whoa! Platform does not support global TLB purges.\n");
+ nptcg = max_purges;
+ if (nptcg == PALO_MAX_TLB_PURGES) {
+ need_ptcg_sem = 0;
+ return;
+ }
+ goto resetsema;
+ }
+ if (palo_override) {
+ if (nptcg != PALO_MAX_TLB_PURGES)
+ need_ptcg_sem = (num_possible_cpus() > nptcg);
+ return;
+ }
+
+ /* In PAL_VM_SUMMARY max_purges == 0 actually means 1 */
+ if (max_purges == 0) max_purges = 1;
+
+ if (firstcpu) {
+ nptcg = max_purges;
+ firstcpu = 0;
+ }
+ if (max_purges < nptcg)
+ nptcg = max_purges;
+ if (nptcg == PAL_MAX_PURGES) {
+ need_ptcg_sem = 0;
+ return;
+ } else
+ need_ptcg_sem = (num_possible_cpus() > nptcg);
+
+resetsema:
+ spinaphore_init(&ptcg_sem, max_purges);
+}
+
+#ifdef CONFIG_SMP
+static void
+ia64_global_tlb_purge (struct mm_struct *mm, unsigned long start,
+ unsigned long end, unsigned long nbits)
+{
+ struct mm_struct *active_mm = current->active_mm;
+
+ toolatetochangeptcgsem = 1;
+
+ if (mm != active_mm) {
+ /* Restore region IDs for mm */
+ if (mm && active_mm) {
+ activate_context(mm);
+ } else {
+ flush_tlb_all();
+ return;
+ }
+ }
+
+ if (need_ptcg_sem)
+ down_spin(&ptcg_sem);
+
+ do {
+ /*
+ * Flush ALAT entries also.
+ */
+ ia64_ptcga(start, (nbits << 2));
+ ia64_srlz_i();
+ start += (1UL << nbits);
+ } while (start < end);
+
+ if (need_ptcg_sem)
+ up_spin(&ptcg_sem);
+
+ if (mm != active_mm) {
+ activate_context(active_mm);
+ }
+}
+#endif /* CONFIG_SMP */
+
+void
+local_flush_tlb_all (void)
+{
+ unsigned long i, j, flags, count0, count1, stride0, stride1, addr;
+
+ addr = local_cpu_data->ptce_base;
+ count0 = local_cpu_data->ptce_count[0];
+ count1 = local_cpu_data->ptce_count[1];
+ stride0 = local_cpu_data->ptce_stride[0];
+ stride1 = local_cpu_data->ptce_stride[1];
+
+ local_irq_save(flags);
+ for (i = 0; i < count0; ++i) {
+ for (j = 0; j < count1; ++j) {
+ ia64_ptce(addr);
+ addr += stride1;
+ }
+ addr += stride0;
+ }
+ local_irq_restore(flags);
+ ia64_srlz_i(); /* srlz.i implies srlz.d */
+}
+
+static void
+__flush_tlb_range (struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ unsigned long size = end - start;
+ unsigned long nbits;
+
+#ifndef CONFIG_SMP
+ if (mm != current->active_mm) {
+ mm->context = 0;
+ return;
+ }
+#endif
+
+ nbits = ia64_fls(size + 0xfff);
+ while (unlikely (((1UL << nbits) & purge.mask) == 0) &&
+ (nbits < purge.max_bits))
+ ++nbits;
+ if (nbits > purge.max_bits)
+ nbits = purge.max_bits;
+ start &= ~((1UL << nbits) - 1);
+
+ preempt_disable();
+#ifdef CONFIG_SMP
+ if (mm != current->active_mm || cpumask_weight(mm_cpumask(mm)) != 1) {
+ ia64_global_tlb_purge(mm, start, end, nbits);
+ preempt_enable();
+ return;
+ }
+#endif
+ do {
+ ia64_ptcl(start, (nbits<<2));
+ start += (1UL << nbits);
+ } while (start < end);
+ preempt_enable();
+ ia64_srlz_i(); /* srlz.i implies srlz.d */
+}
+
+void flush_tlb_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ if (unlikely(end - start >= 1024*1024*1024*1024UL
+ || REGION_NUMBER(start) != REGION_NUMBER(end - 1))) {
+ /*
+ * If we flush more than a tera-byte or across regions, we're
+ * probably better off just flushing the entire TLB(s). This
+ * should be very rare and is not worth optimizing for.
+ */
+ flush_tlb_all();
+ } else {
+ /* flush the address range from the tlb */
+ __flush_tlb_range(vma, start, end);
+ /* flush the virt. page-table area mapping the addr range */
+ __flush_tlb_range(vma, ia64_thash(start), ia64_thash(end));
+ }
+}
+EXPORT_SYMBOL(flush_tlb_range);
+
+void ia64_tlb_init(void)
+{
+ ia64_ptce_info_t ptce_info;
+ u64 tr_pgbits;
+ long status;
+ pal_vm_info_1_u_t vm_info_1;
+ pal_vm_info_2_u_t vm_info_2;
+ int cpu = smp_processor_id();
+
+ if ((status = ia64_pal_vm_page_size(&tr_pgbits, &purge.mask)) != 0) {
+ printk(KERN_ERR "PAL_VM_PAGE_SIZE failed with status=%ld; "
+ "defaulting to architected purge page-sizes.\n", status);
+ purge.mask = 0x115557000UL;
+ }
+ purge.max_bits = ia64_fls(purge.mask);
+
+ ia64_get_ptce(&ptce_info);
+ local_cpu_data->ptce_base = ptce_info.base;
+ local_cpu_data->ptce_count[0] = ptce_info.count[0];
+ local_cpu_data->ptce_count[1] = ptce_info.count[1];
+ local_cpu_data->ptce_stride[0] = ptce_info.stride[0];
+ local_cpu_data->ptce_stride[1] = ptce_info.stride[1];
+
+ local_flush_tlb_all(); /* nuke left overs from bootstrapping... */
+ status = ia64_pal_vm_summary(&vm_info_1, &vm_info_2);
+
+ if (status) {
+ printk(KERN_ERR "ia64_pal_vm_summary=%ld\n", status);
+ per_cpu(ia64_tr_num, cpu) = 8;
+ return;
+ }
+ per_cpu(ia64_tr_num, cpu) = vm_info_1.pal_vm_info_1_s.max_itr_entry+1;
+ if (per_cpu(ia64_tr_num, cpu) >
+ (vm_info_1.pal_vm_info_1_s.max_dtr_entry+1))
+ per_cpu(ia64_tr_num, cpu) =
+ vm_info_1.pal_vm_info_1_s.max_dtr_entry+1;
+ if (per_cpu(ia64_tr_num, cpu) > IA64_TR_ALLOC_MAX) {
+ static int justonce = 1;
+ per_cpu(ia64_tr_num, cpu) = IA64_TR_ALLOC_MAX;
+ if (justonce) {
+ justonce = 0;
+ printk(KERN_DEBUG "TR register number exceeds "
+ "IA64_TR_ALLOC_MAX!\n");
+ }
+ }
+}
+
+/*
+ * is_tr_overlap
+ *
+ * Check overlap with inserted TRs.
+ */
+static int is_tr_overlap(struct ia64_tr_entry *p, u64 va, u64 log_size)
+{
+ u64 tr_log_size;
+ u64 tr_end;
+ u64 va_rr = ia64_get_rr(va);
+ u64 va_rid = RR_TO_RID(va_rr);
+ u64 va_end = va + (1<<log_size) - 1;
+
+ if (va_rid != RR_TO_RID(p->rr))
+ return 0;
+ tr_log_size = (p->itir & 0xff) >> 2;
+ tr_end = p->ifa + (1<<tr_log_size) - 1;
+
+ if (va > tr_end || p->ifa > va_end)
+ return 0;
+ return 1;
+
+}
+
+/*
+ * ia64_insert_tr in virtual mode. Allocate a TR slot
+ *
+ * target_mask : 0x1 : itr, 0x2 : dtr, 0x3 : idtr
+ *
+ * va : virtual address.
+ * pte : pte entries inserted.
+ * log_size: range to be covered.
+ *
+ * Return value: <0 : error No.
+ *
+ * >=0 : slot number allocated for TR.
+ * Must be called with preemption disabled.
+ */
+int ia64_itr_entry(u64 target_mask, u64 va, u64 pte, u64 log_size)
+{
+ int i, r;
+ unsigned long psr;
+ struct ia64_tr_entry *p;
+ int cpu = smp_processor_id();
+
+ if (!ia64_idtrs[cpu]) {
+ ia64_idtrs[cpu] = kmalloc_array(2 * IA64_TR_ALLOC_MAX,
+ sizeof(struct ia64_tr_entry),
+ GFP_KERNEL);
+ if (!ia64_idtrs[cpu])
+ return -ENOMEM;
+ }
+ r = -EINVAL;
+ /*Check overlap with existing TR entries*/
+ if (target_mask & 0x1) {
+ p = ia64_idtrs[cpu];
+ for (i = IA64_TR_ALLOC_BASE; i <= per_cpu(ia64_tr_used, cpu);
+ i++, p++) {
+ if (p->pte & 0x1)
+ if (is_tr_overlap(p, va, log_size)) {
+ printk(KERN_DEBUG "Overlapped Entry"
+ "Inserted for TR Register!!\n");
+ goto out;
+ }
+ }
+ }
+ if (target_mask & 0x2) {
+ p = ia64_idtrs[cpu] + IA64_TR_ALLOC_MAX;
+ for (i = IA64_TR_ALLOC_BASE; i <= per_cpu(ia64_tr_used, cpu);
+ i++, p++) {
+ if (p->pte & 0x1)
+ if (is_tr_overlap(p, va, log_size)) {
+ printk(KERN_DEBUG "Overlapped Entry"
+ "Inserted for TR Register!!\n");
+ goto out;
+ }
+ }
+ }
+
+ for (i = IA64_TR_ALLOC_BASE; i < per_cpu(ia64_tr_num, cpu); i++) {
+ switch (target_mask & 0x3) {
+ case 1:
+ if (!((ia64_idtrs[cpu] + i)->pte & 0x1))
+ goto found;
+ continue;
+ case 2:
+ if (!((ia64_idtrs[cpu] + IA64_TR_ALLOC_MAX + i)->pte & 0x1))
+ goto found;
+ continue;
+ case 3:
+ if (!((ia64_idtrs[cpu] + i)->pte & 0x1) &&
+ !((ia64_idtrs[cpu] + IA64_TR_ALLOC_MAX + i)->pte & 0x1))
+ goto found;
+ continue;
+ default:
+ r = -EINVAL;
+ goto out;
+ }
+ }
+found:
+ if (i >= per_cpu(ia64_tr_num, cpu))
+ return -EBUSY;
+
+ /*Record tr info for mca handler use!*/
+ if (i > per_cpu(ia64_tr_used, cpu))
+ per_cpu(ia64_tr_used, cpu) = i;
+
+ psr = ia64_clear_ic();
+ if (target_mask & 0x1) {
+ ia64_itr(0x1, i, va, pte, log_size);
+ ia64_srlz_i();
+ p = ia64_idtrs[cpu] + i;
+ p->ifa = va;
+ p->pte = pte;
+ p->itir = log_size << 2;
+ p->rr = ia64_get_rr(va);
+ }
+ if (target_mask & 0x2) {
+ ia64_itr(0x2, i, va, pte, log_size);
+ ia64_srlz_i();
+ p = ia64_idtrs[cpu] + IA64_TR_ALLOC_MAX + i;
+ p->ifa = va;
+ p->pte = pte;
+ p->itir = log_size << 2;
+ p->rr = ia64_get_rr(va);
+ }
+ ia64_set_psr(psr);
+ r = i;
+out:
+ return r;
+}
+EXPORT_SYMBOL_GPL(ia64_itr_entry);
+
+/*
+ * ia64_purge_tr
+ *
+ * target_mask: 0x1: purge itr, 0x2 : purge dtr, 0x3 purge idtr.
+ * slot: slot number to be freed.
+ *
+ * Must be called with preemption disabled.
+ */
+void ia64_ptr_entry(u64 target_mask, int slot)
+{
+ int cpu = smp_processor_id();
+ int i;
+ struct ia64_tr_entry *p;
+
+ if (slot < IA64_TR_ALLOC_BASE || slot >= per_cpu(ia64_tr_num, cpu))
+ return;
+
+ if (target_mask & 0x1) {
+ p = ia64_idtrs[cpu] + slot;
+ if ((p->pte&0x1) && is_tr_overlap(p, p->ifa, p->itir>>2)) {
+ p->pte = 0;
+ ia64_ptr(0x1, p->ifa, p->itir>>2);
+ ia64_srlz_i();
+ }
+ }
+
+ if (target_mask & 0x2) {
+ p = ia64_idtrs[cpu] + IA64_TR_ALLOC_MAX + slot;
+ if ((p->pte & 0x1) && is_tr_overlap(p, p->ifa, p->itir>>2)) {
+ p->pte = 0;
+ ia64_ptr(0x2, p->ifa, p->itir>>2);
+ ia64_srlz_i();
+ }
+ }
+
+ for (i = per_cpu(ia64_tr_used, cpu); i >= IA64_TR_ALLOC_BASE; i--) {
+ if (((ia64_idtrs[cpu] + i)->pte & 0x1) ||
+ ((ia64_idtrs[cpu] + IA64_TR_ALLOC_MAX + i)->pte & 0x1))
+ break;
+ }
+ per_cpu(ia64_tr_used, cpu) = i;
+}
+EXPORT_SYMBOL_GPL(ia64_ptr_entry);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-01 05:44:18 +0000