213 lines · c
1// SPDX-License-Identifier: GPL-2.0+2// Copyright 2017 IBM Corp.3#include <linux/interrupt.h>4#include <linux/irqdomain.h>5#include <asm/pnv-ocxl.h>6#include <asm/xive.h>7#include "ocxl_internal.h"8#include "trace.h"9 10struct afu_irq {11 int id;12 int hw_irq;13 unsigned int virq;14 char *name;15 irqreturn_t (*handler)(void *private);16 void (*free_private)(void *private);17 void *private;18};19 20int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset)21{22 return (offset - ctx->afu->irq_base_offset) >> PAGE_SHIFT;23}24 25u64 ocxl_irq_id_to_offset(struct ocxl_context *ctx, int irq_id)26{27 return ctx->afu->irq_base_offset + (irq_id << PAGE_SHIFT);28}29 30int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id,31 irqreturn_t (*handler)(void *private),32 void (*free_private)(void *private),33 void *private)34{35 struct afu_irq *irq;36 int rc;37 38 mutex_lock(&ctx->irq_lock);39 irq = idr_find(&ctx->irq_idr, irq_id);40 if (!irq) {41 rc = -EINVAL;42 goto unlock;43 }44 45 irq->handler = handler;46 irq->private = private;47 irq->free_private = free_private;48 49 rc = 0;50 // Fall through to unlock51 52unlock:53 mutex_unlock(&ctx->irq_lock);54 return rc;55}56EXPORT_SYMBOL_GPL(ocxl_irq_set_handler);57 58static irqreturn_t afu_irq_handler(int virq, void *data)59{60 struct afu_irq *irq = data;61 62 trace_ocxl_afu_irq_receive(virq);63 64 if (irq->handler)65 return irq->handler(irq->private);66 67 return IRQ_HANDLED; // Just drop it on the ground68}69 70static int setup_afu_irq(struct ocxl_context *ctx, struct afu_irq *irq)71{72 int rc;73 74 irq->virq = irq_create_mapping(NULL, irq->hw_irq);75 if (!irq->virq) {76 pr_err("irq_create_mapping failed\n");77 return -ENOMEM;78 }79 pr_debug("hw_irq %d mapped to virq %u\n", irq->hw_irq, irq->virq);80 81 irq->name = kasprintf(GFP_KERNEL, "ocxl-afu-%u", irq->virq);82 if (!irq->name) {83 irq_dispose_mapping(irq->virq);84 return -ENOMEM;85 }86 87 rc = request_irq(irq->virq, afu_irq_handler, 0, irq->name, irq);88 if (rc) {89 kfree(irq->name);90 irq->name = NULL;91 irq_dispose_mapping(irq->virq);92 pr_err("request_irq failed: %d\n", rc);93 return rc;94 }95 return 0;96}97 98static void release_afu_irq(struct afu_irq *irq)99{100 free_irq(irq->virq, irq);101 irq_dispose_mapping(irq->virq);102 kfree(irq->name);103}104 105int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id)106{107 struct afu_irq *irq;108 int rc;109 110 irq = kzalloc(sizeof(struct afu_irq), GFP_KERNEL);111 if (!irq)112 return -ENOMEM;113 114 /*115 * We limit the number of afu irqs per context and per link to116 * avoid a single process or user depleting the pool of IPIs117 */118 119 mutex_lock(&ctx->irq_lock);120 121 irq->id = idr_alloc(&ctx->irq_idr, irq, 0, MAX_IRQ_PER_CONTEXT,122 GFP_KERNEL);123 if (irq->id < 0) {124 rc = -ENOSPC;125 goto err_unlock;126 }127 128 rc = ocxl_link_irq_alloc(ctx->afu->fn->link, &irq->hw_irq);129 if (rc)130 goto err_idr;131 132 rc = setup_afu_irq(ctx, irq);133 if (rc)134 goto err_alloc;135 136 trace_ocxl_afu_irq_alloc(ctx->pasid, irq->id, irq->virq, irq->hw_irq);137 mutex_unlock(&ctx->irq_lock);138 139 *irq_id = irq->id;140 141 return 0;142 143err_alloc:144 ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq);145err_idr:146 idr_remove(&ctx->irq_idr, irq->id);147err_unlock:148 mutex_unlock(&ctx->irq_lock);149 kfree(irq);150 return rc;151}152EXPORT_SYMBOL_GPL(ocxl_afu_irq_alloc);153 154static void afu_irq_free(struct afu_irq *irq, struct ocxl_context *ctx)155{156 trace_ocxl_afu_irq_free(ctx->pasid, irq->id);157 if (ctx->mapping)158 unmap_mapping_range(ctx->mapping,159 ocxl_irq_id_to_offset(ctx, irq->id),160 1 << PAGE_SHIFT, 1);161 release_afu_irq(irq);162 if (irq->free_private)163 irq->free_private(irq->private);164 ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq);165 kfree(irq);166}167 168int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id)169{170 struct afu_irq *irq;171 172 mutex_lock(&ctx->irq_lock);173 174 irq = idr_find(&ctx->irq_idr, irq_id);175 if (!irq) {176 mutex_unlock(&ctx->irq_lock);177 return -EINVAL;178 }179 idr_remove(&ctx->irq_idr, irq->id);180 afu_irq_free(irq, ctx);181 mutex_unlock(&ctx->irq_lock);182 return 0;183}184EXPORT_SYMBOL_GPL(ocxl_afu_irq_free);185 186void ocxl_afu_irq_free_all(struct ocxl_context *ctx)187{188 struct afu_irq *irq;189 int id;190 191 mutex_lock(&ctx->irq_lock);192 idr_for_each_entry(&ctx->irq_idr, irq, id)193 afu_irq_free(irq, ctx);194 mutex_unlock(&ctx->irq_lock);195}196 197u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id)198{199 struct xive_irq_data *xd;200 struct afu_irq *irq;201 u64 addr = 0;202 203 mutex_lock(&ctx->irq_lock);204 irq = idr_find(&ctx->irq_idr, irq_id);205 if (irq) {206 xd = irq_get_handler_data(irq->virq);207 addr = xd ? xd->trig_page : 0;208 }209 mutex_unlock(&ctx->irq_lock);210 return addr;211}212EXPORT_SYMBOL_GPL(ocxl_afu_irq_get_addr);213