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, id: 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(lock: &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 = 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, hwirq: 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, fmt: "ocxl-afu-%u" , irq->virq); |
82 | if (!irq->name) { |
83 | irq_dispose_mapping(virq: irq->virq); |
84 | return -ENOMEM; |
85 | } |
86 | |
87 | rc = request_irq(irq: irq->virq, handler: afu_irq_handler, flags: 0, name: irq->name, dev: irq); |
88 | if (rc) { |
89 | kfree(objp: irq->name); |
90 | irq->name = NULL; |
91 | irq_dispose_mapping(virq: 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(virq: irq->virq); |
102 | kfree(objp: 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(size: 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, ptr: irq, start: 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(link_handle: ctx->afu->fn->link, hw_irq: &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(pasid: ctx->pasid, irq_id: irq->id, virq: irq->virq, hw_irq: irq->hw_irq); |
137 | mutex_unlock(lock: &ctx->irq_lock); |
138 | |
139 | *irq_id = irq->id; |
140 | |
141 | return 0; |
142 | |
143 | err_alloc: |
144 | ocxl_link_free_irq(link_handle: ctx->afu->fn->link, hw_irq: irq->hw_irq); |
145 | err_idr: |
146 | idr_remove(&ctx->irq_idr, id: irq->id); |
147 | err_unlock: |
148 | mutex_unlock(lock: &ctx->irq_lock); |
149 | kfree(objp: 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(pasid: ctx->pasid, irq_id: irq->id); |
157 | if (ctx->mapping) |
158 | unmap_mapping_range(mapping: ctx->mapping, |
159 | holebegin: ocxl_irq_id_to_offset(ctx, irq_id: irq->id), |
160 | holelen: 1 << PAGE_SHIFT, even_cows: 1); |
161 | release_afu_irq(irq); |
162 | if (irq->free_private) |
163 | irq->free_private(irq->private); |
164 | ocxl_link_free_irq(link_handle: ctx->afu->fn->link, hw_irq: irq->hw_irq); |
165 | kfree(objp: 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, id: irq_id); |
175 | if (!irq) { |
176 | mutex_unlock(lock: &ctx->irq_lock); |
177 | return -EINVAL; |
178 | } |
179 | idr_remove(&ctx->irq_idr, id: irq->id); |
180 | afu_irq_free(irq, ctx); |
181 | mutex_unlock(lock: &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(lock: &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, id: irq_id); |
205 | if (irq) { |
206 | xd = irq_get_handler_data(irq->virq); |
207 | addr = xd ? xd->trig_page : 0; |
208 | } |
209 | mutex_unlock(lock: &ctx->irq_lock); |
210 | return addr; |
211 | } |
212 | EXPORT_SYMBOL_GPL(ocxl_afu_irq_get_addr); |
213 | |