1 /* $NetBSD: nouveau_nvif_notify.c,v 1.5 2021/12/19 10:51:57 riastradh Exp $ */
2
3 /*
4 * Copyright 2014 Red Hat Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 *
24 * Authors: Ben Skeggs <bskeggs@redhat.com>
25 */
26
27 #include <sys/cdefs.h>
28 __KERNEL_RCSID(0, "$NetBSD: nouveau_nvif_notify.c,v 1.5 2021/12/19 10:51:57 riastradh Exp $");
29
30 #include <nvif/client.h>
31 #include <nvif/driver.h>
32 #include <nvif/notify.h>
33 #include <nvif/object.h>
34 #include <nvif/ioctl.h>
35 #include <nvif/event.h>
36
37 static inline int
nvif_notify_put_(struct nvif_notify * notify)38 nvif_notify_put_(struct nvif_notify *notify)
39 {
40 struct nvif_object *object = notify->object;
41 struct {
42 struct nvif_ioctl_v0 ioctl;
43 struct nvif_ioctl_ntfy_put_v0 ntfy;
44 } args = {
45 .ioctl.type = NVIF_IOCTL_V0_NTFY_PUT,
46 .ntfy.index = notify->index,
47 };
48
49 if (atomic_inc_return(¬ify->putcnt) != 1)
50 return 0;
51
52 return nvif_object_ioctl(object, &args, sizeof(args), NULL);
53 }
54
55 int
nvif_notify_put(struct nvif_notify * notify)56 nvif_notify_put(struct nvif_notify *notify)
57 {
58 if (likely(notify->object) &&
59 test_and_clear_bit(NVIF_NOTIFY_USER, ¬ify->flags)) {
60 int ret = nvif_notify_put_(notify);
61 if (test_bit(NVIF_NOTIFY_WORK, ¬ify->flags))
62 flush_work(¬ify->work);
63 return ret;
64 }
65 return 0;
66 }
67
68 static inline int
nvif_notify_get_(struct nvif_notify * notify)69 nvif_notify_get_(struct nvif_notify *notify)
70 {
71 struct nvif_object *object = notify->object;
72 struct {
73 struct nvif_ioctl_v0 ioctl;
74 struct nvif_ioctl_ntfy_get_v0 ntfy;
75 } args = {
76 .ioctl.type = NVIF_IOCTL_V0_NTFY_GET,
77 .ntfy.index = notify->index,
78 };
79
80 if (atomic_dec_return(¬ify->putcnt) != 0)
81 return 0;
82
83 return nvif_object_ioctl(object, &args, sizeof(args), NULL);
84 }
85
86 int
nvif_notify_get(struct nvif_notify * notify)87 nvif_notify_get(struct nvif_notify *notify)
88 {
89 if (likely(notify->object) &&
90 !test_and_set_bit(NVIF_NOTIFY_USER, ¬ify->flags))
91 return nvif_notify_get_(notify);
92 return 0;
93 }
94
95 static inline int
nvif_notify_func(struct nvif_notify * notify,bool keep)96 nvif_notify_func(struct nvif_notify *notify, bool keep)
97 {
98 int ret = notify->func(notify);
99 if (ret == NVIF_NOTIFY_KEEP ||
100 !test_and_clear_bit(NVIF_NOTIFY_USER, ¬ify->flags)) {
101 if (!keep)
102 atomic_dec(¬ify->putcnt);
103 else
104 nvif_notify_get_(notify);
105 }
106 return ret;
107 }
108
109 static void
nvif_notify_work(struct work_struct * work)110 nvif_notify_work(struct work_struct *work)
111 {
112 struct nvif_notify *notify = container_of(work, typeof(*notify), work);
113 nvif_notify_func(notify, true);
114 }
115
116 int
nvif_notify(const void * header,u32 length,const void * data,u32 size)117 nvif_notify(const void *header, u32 length, const void *data, u32 size)
118 {
119 struct nvif_notify *notify = NULL;
120 const union {
121 struct nvif_notify_rep_v0 v0;
122 } *args = header;
123 int ret = NVIF_NOTIFY_DROP;
124
125 if (length == sizeof(args->v0) && args->v0.version == 0) {
126 if (WARN_ON(args->v0.route))
127 return NVIF_NOTIFY_DROP;
128 notify = (void *)(unsigned long)args->v0.token;
129 }
130
131 if (!WARN_ON(notify == NULL)) {
132 struct nvif_client *client = notify->object->client;
133 if (!WARN_ON(notify->size != size)) {
134 atomic_inc(¬ify->putcnt);
135 if (test_bit(NVIF_NOTIFY_WORK, ¬ify->flags)) {
136 memcpy(__UNCONST(notify->data), data, size);
137 schedule_work(¬ify->work);
138 return NVIF_NOTIFY_DROP;
139 }
140 notify->data = data;
141 ret = nvif_notify_func(notify, client->driver->keep);
142 notify->data = NULL;
143 }
144 }
145
146 return ret;
147 }
148
149 int
nvif_notify_fini(struct nvif_notify * notify)150 nvif_notify_fini(struct nvif_notify *notify)
151 {
152 struct nvif_object *object = notify->object;
153 struct {
154 struct nvif_ioctl_v0 ioctl;
155 struct nvif_ioctl_ntfy_del_v0 ntfy;
156 } args = {
157 .ioctl.type = NVIF_IOCTL_V0_NTFY_DEL,
158 .ntfy.index = notify->index,
159 };
160 int ret = nvif_notify_put(notify);
161 if (ret >= 0 && object) {
162 ret = nvif_object_ioctl(object, &args, sizeof(args), NULL);
163 notify->object = NULL;
164 kfree(__UNCONST(notify->data));
165 }
166 return ret;
167 }
168
169 int
nvif_notify_init(struct nvif_object * object,int (* func)(struct nvif_notify *),bool work,u8 event,void * data,u32 size,u32 reply,struct nvif_notify * notify)170 nvif_notify_init(struct nvif_object *object, int (*func)(struct nvif_notify *),
171 bool work, u8 event, void *data, u32 size, u32 reply,
172 struct nvif_notify *notify)
173 {
174 struct {
175 struct nvif_ioctl_v0 ioctl;
176 struct nvif_ioctl_ntfy_new_v0 ntfy;
177 struct nvif_notify_req_v0 req;
178 } *args;
179 int ret = -ENOMEM;
180
181 notify->object = object;
182 notify->flags = 0;
183 atomic_set(¬ify->putcnt, 1);
184 notify->func = func;
185 notify->data = NULL;
186 notify->size = reply;
187 if (work) {
188 INIT_WORK(¬ify->work, nvif_notify_work);
189 set_bit(NVIF_NOTIFY_WORK, ¬ify->flags);
190 notify->data = kmalloc(notify->size, GFP_KERNEL);
191 if (!notify->data)
192 goto done;
193 }
194
195 if (!(args = kmalloc(sizeof(*args) + size, GFP_KERNEL)))
196 goto done;
197 args->ioctl.version = 0;
198 args->ioctl.type = NVIF_IOCTL_V0_NTFY_NEW;
199 args->ntfy.version = 0;
200 args->ntfy.event = event;
201 args->req.version = 0;
202 args->req.reply = notify->size;
203 args->req.route = 0;
204 args->req.token = (unsigned long)(void *)notify;
205
206 memcpy(args->req.data, data, size);
207 ret = nvif_object_ioctl(object, args, sizeof(*args) + size, NULL);
208 notify->index = args->ntfy.index;
209 kfree(args);
210 done:
211 if (ret)
212 nvif_notify_fini(notify);
213 return ret;
214 }
215