1 files changed, 0 insertions, 341 deletions
diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
deleted file mode 100644
index 2c64f55cf01f..000000000000
--- a/drivers/misc/cxl/fault.c
+++ /dev/null
@@ -1,341 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright 2014 IBM Corp.
- */
-
-#include <linux/workqueue.h>
-#include <linux/sched/signal.h>
-#include <linux/sched/mm.h>
-#include <linux/pid.h>
-#include <linux/mm.h>
-#include <linux/moduleparam.h>
-
-#undef MODULE_PARAM_PREFIX
-#define MODULE_PARAM_PREFIX "cxl" "."
-#include <asm/current.h>
-#include <asm/copro.h>
-#include <asm/mmu.h>
-
-#include "cxl.h"
-#include "trace.h"
-
-static bool sste_matches(struct cxl_sste *sste, struct copro_slb *slb)
-{
-	return ((sste->vsid_data == cpu_to_be64(slb->vsid)) &&
-		(sste->esid_data == cpu_to_be64(slb->esid)));
-}
-
-/*
- * This finds a free SSTE for the given SLB, or returns NULL if it's already in
- * the segment table.
- */
-static struct cxl_sste *find_free_sste(struct cxl_context *ctx,
-				       struct copro_slb *slb)
-{
-	struct cxl_sste *primary, *sste, *ret = NULL;
-	unsigned int mask = (ctx->sst_size >> 7) - 1; /* SSTP0[SegTableSize] */
-	unsigned int entry;
-	unsigned int hash;
-
-	if (slb->vsid & SLB_VSID_B_1T)
-		hash = (slb->esid >> SID_SHIFT_1T) & mask;
-	else /* 256M */
-		hash = (slb->esid >> SID_SHIFT) & mask;
-
-	primary = ctx->sstp + (hash << 3);
-
-	for (entry = 0, sste = primary; entry < 8; entry++, sste++) {
-		if (!ret && !(be64_to_cpu(sste->esid_data) & SLB_ESID_V))
-			ret = sste;
-		if (sste_matches(sste, slb))
-			return NULL;
-	}
-	if (ret)
-		return ret;
-
-	/* Nothing free, select an entry to cast out */
-	ret = primary + ctx->sst_lru;
-	ctx->sst_lru = (ctx->sst_lru + 1) & 0x7;
-
-	return ret;
-}
-
-static void cxl_load_segment(struct cxl_context *ctx, struct copro_slb *slb)
-{
-	/* mask is the group index, we search primary and secondary here. */
-	struct cxl_sste *sste;
-	unsigned long flags;
-
-	spin_lock_irqsave(&ctx->sste_lock, flags);
-	sste = find_free_sste(ctx, slb);
-	if (!sste)
-		goto out_unlock;
-
-	pr_devel("CXL Populating SST[%li]: %#llx %#llx\n",
-			sste - ctx->sstp, slb->vsid, slb->esid);
-	trace_cxl_ste_write(ctx, sste - ctx->sstp, slb->esid, slb->vsid);
-
-	sste->vsid_data = cpu_to_be64(slb->vsid);
-	sste->esid_data = cpu_to_be64(slb->esid);
-out_unlock:
-	spin_unlock_irqrestore(&ctx->sste_lock, flags);
-}
-
-static int cxl_fault_segment(struct cxl_context *ctx, struct mm_struct *mm,
-			     u64 ea)
-{
-	struct copro_slb slb = {0,0};
-	int rc;
-
-	if (!(rc = copro_calculate_slb(mm, ea, &slb))) {
-		cxl_load_segment(ctx, &slb);
-	}
-
-	return rc;
-}
-
-static void cxl_ack_ae(struct cxl_context *ctx)
-{
-	unsigned long flags;
-
-	cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_AE, 0);
-
-	spin_lock_irqsave(&ctx->lock, flags);
-	ctx->pending_fault = true;
-	ctx->fault_addr = ctx->dar;
-	ctx->fault_dsisr = ctx->dsisr;
-	spin_unlock_irqrestore(&ctx->lock, flags);
-
-	wake_up_all(&ctx->wq);
-}
-
-static int cxl_handle_segment_miss(struct cxl_context *ctx,
-				   struct mm_struct *mm, u64 ea)
-{
-	int rc;
-
-	pr_devel("CXL interrupt: Segment fault pe: %i ea: %#llx\n", ctx->pe, ea);
-	trace_cxl_ste_miss(ctx, ea);
-
-	if ((rc = cxl_fault_segment(ctx, mm, ea)))
-		cxl_ack_ae(ctx);
-	else {
-
-		mb(); /* Order seg table write to TFC MMIO write */
-		cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_R, 0);
-	}
-
-	return IRQ_HANDLED;
-}
-
-int cxl_handle_mm_fault(struct mm_struct *mm, u64 dsisr, u64 dar)
-{
-	vm_fault_t flt = 0;
-	int result;
-	unsigned long access, flags, inv_flags = 0;
-
-	/*
-	 * Add the fault handling cpu to task mm cpumask so that we
-	 * can do a safe lockless page table walk when inserting the
-	 * hash page table entry. This function get called with a
-	 * valid mm for user space addresses. Hence using the if (mm)
-	 * check is sufficient here.
-	 */
-	if (mm && !cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm))) {
-		cpumask_set_cpu(smp_processor_id(), mm_cpumask(mm));
-		/*
-		 * We need to make sure we walk the table only after
-		 * we update the cpumask. The other side of the barrier
-		 * is explained in serialize_against_pte_lookup()
-		 */
-		smp_mb();
-	}
-	if ((result = copro_handle_mm_fault(mm, dar, dsisr, &flt))) {
-		pr_devel("copro_handle_mm_fault failed: %#x\n", result);
-		return result;
-	}
-
-	if (!radix_enabled()) {
-		/*
-		 * update_mmu_cache() will not have loaded the hash since current->trap
-		 * is not a 0x400 or 0x300, so just call hash_page_mm() here.
-		 */
-		access = _PAGE_PRESENT | _PAGE_READ;
-		if (dsisr & CXL_PSL_DSISR_An_S)
-			access |= _PAGE_WRITE;
-
-		if (!mm && (get_region_id(dar) != USER_REGION_ID))
-			access |= _PAGE_PRIVILEGED;
-
-		if (dsisr & DSISR_NOHPTE)
-			inv_flags |= HPTE_NOHPTE_UPDATE;
-
-		local_irq_save(flags);
-		hash_page_mm(mm, dar, access, 0x300, inv_flags);
-		local_irq_restore(flags);
-	}
-	return 0;
-}
-
-static void cxl_handle_page_fault(struct cxl_context *ctx,
-				  struct mm_struct *mm,
-				  u64 dsisr, u64 dar)
-{
-	trace_cxl_pte_miss(ctx, dsisr, dar);
-
-	if (cxl_handle_mm_fault(mm, dsisr, dar)) {
-		cxl_ack_ae(ctx);
-	} else {
-		pr_devel("Page fault successfully handled for pe: %i!\n", ctx->pe);
-		cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_R, 0);
-	}
-}
-
-/*
- * Returns the mm_struct corresponding to the context ctx.
- * mm_users == 0, the context may be in the process of being closed.
- */
-static struct mm_struct *get_mem_context(struct cxl_context *ctx)
-{
-	if (ctx->mm == NULL)
-		return NULL;
-
-	if (!mmget_not_zero(ctx->mm))
-		return NULL;
-
-	return ctx->mm;
-}
-
-static bool cxl_is_segment_miss(struct cxl_context *ctx, u64 dsisr)
-{
-	if ((cxl_is_power8() && (dsisr & CXL_PSL_DSISR_An_DS)))
-		return true;
-
-	return false;
-}
-
-static bool cxl_is_page_fault(struct cxl_context *ctx, u64 dsisr)
-{
-	if ((cxl_is_power8()) && (dsisr & CXL_PSL_DSISR_An_DM))
-		return true;
-
-	if (cxl_is_power9())
-		return true;
-
-	return false;
-}
-
-void cxl_handle_fault(struct work_struct *fault_work)
-{
-	struct cxl_context *ctx =
-		container_of(fault_work, struct cxl_context, fault_work);
-	u64 dsisr = ctx->dsisr;
-	u64 dar = ctx->dar;
-	struct mm_struct *mm = NULL;
-
-	if (cpu_has_feature(CPU_FTR_HVMODE)) {
-		if (cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An) != dsisr ||
-		    cxl_p2n_read(ctx->afu, CXL_PSL_DAR_An) != dar ||
-		    cxl_p2n_read(ctx->afu, CXL_PSL_PEHandle_An) != ctx->pe) {
-			/* Most likely explanation is harmless - a dedicated
-			 * process has detached and these were cleared by the
-			 * PSL purge, but warn about it just in case
-			 */
-			dev_notice(&ctx->afu->dev, "cxl_handle_fault: Translation fault regs changed\n");
-			return;
-		}
-	}
-
-	/* Early return if the context is being / has been detached */
-	if (ctx->status == CLOSED) {
-		cxl_ack_ae(ctx);
-		return;
-	}
-
-	pr_devel("CXL BOTTOM HALF handling fault for afu pe: %i. "
-		"DSISR: %#llx DAR: %#llx\n", ctx->pe, dsisr, dar);
-
-	if (!ctx->kernel) {
-
-		mm = get_mem_context(ctx);
-		if (mm == NULL) {
-			pr_devel("%s: unable to get mm for pe=%d pid=%i\n",
-				 __func__, ctx->pe, pid_nr(ctx->pid));
-			cxl_ack_ae(ctx);
-			return;
-		} else {
-			pr_devel("Handling page fault for pe=%d pid=%i\n",
-				 ctx->pe, pid_nr(ctx->pid));
-		}
-	}
-
-	if (cxl_is_segment_miss(ctx, dsisr))
-		cxl_handle_segment_miss(ctx, mm, dar);
-	else if (cxl_is_page_fault(ctx, dsisr))
-		cxl_handle_page_fault(ctx, mm, dsisr, dar);
-	else
-		WARN(1, "cxl_handle_fault has nothing to handle\n");
-
-	if (mm)
-		mmput(mm);
-}
-
-static u64 next_segment(u64 ea, u64 vsid)
-{
-	if (vsid & SLB_VSID_B_1T)
-		ea |= (1ULL << 40) - 1;
-	else
-		ea |= (1ULL << 28) - 1;
-
-	return ea + 1;
-}
-
-static void cxl_prefault_vma(struct cxl_context *ctx, struct mm_struct *mm)
-{
-	u64 ea, last_esid = 0;
-	struct copro_slb slb;
-	VMA_ITERATOR(vmi, mm, 0);
-	struct vm_area_struct *vma;
-	int rc;
-
-	mmap_read_lock(mm);
-	for_each_vma(vmi, vma) {
-		for (ea = vma->vm_start; ea < vma->vm_end;
-				ea = next_segment(ea, slb.vsid)) {
-			rc = copro_calculate_slb(mm, ea, &slb);
-			if (rc)
-				continue;
-
-			if (last_esid == slb.esid)
-				continue;
-
-			cxl_load_segment(ctx, &slb);
-			last_esid = slb.esid;
-		}
-	}
-	mmap_read_unlock(mm);
-}
-
-void cxl_prefault(struct cxl_context *ctx, u64 wed)
-{
-	struct mm_struct *mm = get_mem_context(ctx);
-
-	if (mm == NULL) {
-		pr_devel("cxl_prefault unable to get mm %i\n",
-			 pid_nr(ctx->pid));
-		return;
-	}
-
-	switch (ctx->afu->prefault_mode) {
-	case CXL_PREFAULT_WED:
-		cxl_fault_segment(ctx, mm, wed);
-		break;
-	case CXL_PREFAULT_ALL:
-		cxl_prefault_vma(ctx, mm);
-		break;
-	default:
-		break;
-	}
-
-	mmput(mm);
-}