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 10 struct 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 20 int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset) 21 { 22 return (offset - ctx->afu->irq_base_offset) >> PAGE_SHIFT; 23 } 24 25 u64 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 30 int 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 unlock 51 52 unlock: 53 mutex_unlock(&ctx->irq_lock); 54 return rc; 55 } 56 EXPORT_SYMBOL_GPL(ocxl_irq_set_handler); 57 58 static irqreturn_t afu_irq_handler(int virq, void *data) 59 { 60 struct afu_irq *irq = (struct afu_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 ground 68 } 69 70 static 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 98 static 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 } 104 105 int 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 to 116 * avoid a single process or user depleting the pool of IPIs 117 */ 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; 142 143 err_alloc: 144 ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq); 145 err_idr: 146 idr_remove(&ctx->irq_idr, irq->id); 147 err_unlock: 148 mutex_unlock(&ctx->irq_lock); 149 kfree(irq); 150 return rc; 151 } 152 EXPORT_SYMBOL_GPL(ocxl_afu_irq_alloc); 153 154 static 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 } 167 168 int 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 } 184 EXPORT_SYMBOL_GPL(ocxl_afu_irq_free); 185 186 void 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 } 196 197 u64 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 } 212 EXPORT_SYMBOL_GPL(ocxl_afu_irq_get_addr); 213