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 <asm/xive.h> 6 #include "ocxl_internal.h" 7 #include "trace.h" 8 9 struct afu_irq { 10 int id; 11 int hw_irq; 12 unsigned int virq; 13 char *name; 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 if (rc) 129 goto err_idr; 130 131 rc = setup_afu_irq(ctx, irq); 132 if (rc) 133 goto err_alloc; 134 135 trace_ocxl_afu_irq_alloc(ctx->pasid, irq->id, irq->virq, irq->hw_irq); 136 mutex_unlock(&ctx->irq_lock); 137 138 *irq_id = irq->id; 139 140 return 0; 141 142 err_alloc: 143 ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq); 144 err_idr: 145 idr_remove(&ctx->irq_idr, irq->id); 146 err_unlock: 147 mutex_unlock(&ctx->irq_lock); 148 kfree(irq); 149 return rc; 150 } 151 EXPORT_SYMBOL_GPL(ocxl_afu_irq_alloc); 152 153 static void afu_irq_free(struct afu_irq *irq, struct ocxl_context *ctx) 154 { 155 trace_ocxl_afu_irq_free(ctx->pasid, irq->id); 156 if (ctx->mapping) 157 unmap_mapping_range(ctx->mapping, 158 ocxl_irq_id_to_offset(ctx, irq->id), 159 1 << PAGE_SHIFT, 1); 160 release_afu_irq(irq); 161 if (irq->free_private) 162 irq->free_private(irq->private); 163 ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq); 164 kfree(irq); 165 } 166 167 int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id) 168 { 169 struct afu_irq *irq; 170 171 mutex_lock(&ctx->irq_lock); 172 173 irq = idr_find(&ctx->irq_idr, irq_id); 174 if (!irq) { 175 mutex_unlock(&ctx->irq_lock); 176 return -EINVAL; 177 } 178 idr_remove(&ctx->irq_idr, irq->id); 179 afu_irq_free(irq, ctx); 180 mutex_unlock(&ctx->irq_lock); 181 return 0; 182 } 183 EXPORT_SYMBOL_GPL(ocxl_afu_irq_free); 184 185 void ocxl_afu_irq_free_all(struct ocxl_context *ctx) 186 { 187 struct afu_irq *irq; 188 int id; 189 190 mutex_lock(&ctx->irq_lock); 191 idr_for_each_entry(&ctx->irq_idr, irq, id) 192 afu_irq_free(irq, ctx); 193 mutex_unlock(&ctx->irq_lock); 194 } 195 196 u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id) 197 { 198 struct xive_irq_data *xd; 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 xd = irq_get_handler_data(irq->virq); 206 addr = xd ? xd->trig_page : 0; 207 } 208 mutex_unlock(&ctx->irq_lock); 209 return addr; 210 } 211 EXPORT_SYMBOL_GPL(ocxl_afu_irq_get_addr); 212