1 // SPDX-License-Identifier: GPL-2.0+ 2 // Copyright 2017 IBM Corp. 3 #include <linux/interrupt.h> 4 #include <asm/pnv-ocxl.h> 5 #include "ocxl_internal.h" 6 #include "trace.h" 7 8 struct afu_irq { 9 int id; 10 int hw_irq; 11 unsigned int virq; 12 char *name; 13 u64 trigger_page; 14 irqreturn_t (*handler)(void *private); 15 void (*free_private)(void *private); 16 void *private; 17 }; 18 19 int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset) 20 { 21 return (offset - ctx->afu->irq_base_offset) >> PAGE_SHIFT; 22 } 23 24 u64 ocxl_irq_id_to_offset(struct ocxl_context *ctx, int irq_id) 25 { 26 return ctx->afu->irq_base_offset + (irq_id << PAGE_SHIFT); 27 } 28 29 int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id, 30 irqreturn_t (*handler)(void *private), 31 void (*free_private)(void *private), 32 void *private) 33 { 34 struct afu_irq *irq; 35 int rc; 36 37 mutex_lock(&ctx->irq_lock); 38 irq = idr_find(&ctx->irq_idr, irq_id); 39 if (!irq) { 40 rc = -EINVAL; 41 goto unlock; 42 } 43 44 irq->handler = handler; 45 irq->private = private; 46 irq->free_private = free_private; 47 48 rc = 0; 49 // Fall through to unlock 50 51 unlock: 52 mutex_unlock(&ctx->irq_lock); 53 return rc; 54 } 55 EXPORT_SYMBOL_GPL(ocxl_irq_set_handler); 56 57 static irqreturn_t afu_irq_handler(int virq, void *data) 58 { 59 struct afu_irq *irq = (struct afu_irq *) data; 60 61 trace_ocxl_afu_irq_receive(virq); 62 63 if (irq->handler) 64 return irq->handler(irq->private); 65 66 return IRQ_HANDLED; // Just drop it on the ground 67 } 68 69 static int setup_afu_irq(struct ocxl_context *ctx, struct afu_irq *irq) 70 { 71 int rc; 72 73 irq->virq = irq_create_mapping(NULL, irq->hw_irq); 74 if (!irq->virq) { 75 pr_err("irq_create_mapping failed\n"); 76 return -ENOMEM; 77 } 78 pr_debug("hw_irq %d mapped to virq %u\n", irq->hw_irq, irq->virq); 79 80 irq->name = kasprintf(GFP_KERNEL, "ocxl-afu-%u", irq->virq); 81 if (!irq->name) { 82 irq_dispose_mapping(irq->virq); 83 return -ENOMEM; 84 } 85 86 rc = request_irq(irq->virq, afu_irq_handler, 0, irq->name, irq); 87 if (rc) { 88 kfree(irq->name); 89 irq->name = NULL; 90 irq_dispose_mapping(irq->virq); 91 pr_err("request_irq failed: %d\n", rc); 92 return rc; 93 } 94 return 0; 95 } 96 97 static void release_afu_irq(struct afu_irq *irq) 98 { 99 free_irq(irq->virq, irq); 100 irq_dispose_mapping(irq->virq); 101 kfree(irq->name); 102 } 103 104 int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id) 105 { 106 struct afu_irq *irq; 107 int rc; 108 109 irq = kzalloc(sizeof(struct afu_irq), GFP_KERNEL); 110 if (!irq) 111 return -ENOMEM; 112 113 /* 114 * We limit the number of afu irqs per context and per link to 115 * avoid a single process or user depleting the pool of IPIs 116 */ 117 118 mutex_lock(&ctx->irq_lock); 119 120 irq->id = idr_alloc(&ctx->irq_idr, irq, 0, MAX_IRQ_PER_CONTEXT, 121 GFP_KERNEL); 122 if (irq->id < 0) { 123 rc = -ENOSPC; 124 goto err_unlock; 125 } 126 127 rc = ocxl_link_irq_alloc(ctx->afu->fn->link, &irq->hw_irq, 128 &irq->trigger_page); 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 afu_irq *irq; 200 u64 addr = 0; 201 202 mutex_lock(&ctx->irq_lock); 203 irq = idr_find(&ctx->irq_idr, irq_id); 204 if (irq) 205 addr = irq->trigger_page; 206 mutex_unlock(&ctx->irq_lock); 207 return addr; 208 } 209 EXPORT_SYMBOL_GPL(ocxl_afu_irq_get_addr); 210