xref: /illumos-gate/usr/src/uts/intel/io/amdzen/zen_udf.c (revision dd72704bd9e794056c558153663c739e2012d721)
1 /*
2  * This file and its contents are supplied under the terms of the
3  * Common Development and Distribution License ("CDDL"), version 1.0.
4  * You may only use this file in accordance with the terms of version
5  * 1.0 of the CDDL.
6  *
7  * A full copy of the text of the CDDL should have accompanied this
8  * source.  A copy of the CDDL is also available via the Internet at
9  * http://www.illumos.org/license/CDDL.
10  */
11 
12 /*
13  * Copyright 2022 Oxide Computer Company
14  */
15 
16 /*
17  * A companion to zen_udf(4D) that allows user access to read the data fabric
18  * for development purposes.
19  */
20 
21 #include <sys/types.h>
22 #include <sys/file.h>
23 #include <sys/errno.h>
24 #include <sys/open.h>
25 #include <sys/cred.h>
26 #include <sys/ddi.h>
27 #include <sys/sunddi.h>
28 #include <sys/stat.h>
29 #include <sys/conf.h>
30 #include <sys/devops.h>
31 #include <sys/cmn_err.h>
32 #include <sys/policy.h>
33 #include <amdzen_client.h>
34 
35 #include <zen_udf.h>
36 
37 typedef struct zen_udf {
38 	dev_info_t *zudf_dip;
39 	uint_t zudf_ndfs;
40 } zen_udf_t;
41 
42 static zen_udf_t zen_udf_data;
43 
44 static int
45 zen_udf_open(dev_t *devp, int flags, int otype, cred_t *credp)
46 {
47 	minor_t m;
48 	zen_udf_t *zen_udf = &zen_udf_data;
49 
50 	if (crgetzoneid(credp) != GLOBAL_ZONEID ||
51 	    secpolicy_hwmanip(credp) != 0) {
52 		return (EPERM);
53 	}
54 
55 	if ((flags & (FEXCL | FNDELAY | FNONBLOCK)) != 0) {
56 		return (EINVAL);
57 	}
58 
59 	if (otype != OTYP_CHR) {
60 		return (EINVAL);
61 	}
62 
63 	m = getminor(*devp);
64 	if (m >= zen_udf->zudf_ndfs) {
65 		return (ENXIO);
66 	}
67 
68 	return (0);
69 }
70 
71 static int
72 zen_udf_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *credp,
73     int *rvalp)
74 {
75 	uint_t dfno;
76 	zen_udf_t *zen_udf = &zen_udf_data;
77 	zen_udf_io_t zui;
78 	df_reg_def_t def;
79 
80 	if (cmd != ZEN_UDF_READ32 && cmd != ZEN_UDF_READ64) {
81 		return (ENOTTY);
82 	}
83 
84 	dfno = getminor(dev);
85 	if (dfno >= zen_udf->zudf_ndfs) {
86 		return (ENXIO);
87 	}
88 
89 	if (crgetzoneid(credp) != GLOBAL_ZONEID ||
90 	    secpolicy_hwmanip(credp) != 0) {
91 		return (EPERM);
92 	}
93 
94 	if (ddi_copyin((void *)arg, &zui, sizeof (zui), mode & FKIOCTL) != 0) {
95 		return (EFAULT);
96 	}
97 
98 	/*
99 	 * Cons up a register definition based on the user request. We set the
100 	 * gen to our current one.
101 	 */
102 	def.drd_gens = amdzen_c_df_rev();
103 	def.drd_func = zui.zui_func;
104 	def.drd_reg = zui.zui_reg;
105 
106 	if (cmd == ZEN_UDF_READ32) {
107 		int ret;
108 		uint32_t data;
109 
110 		ret = amdzen_c_df_read32(dfno, zui.zui_inst, def, &data);
111 		if (ret != 0) {
112 			return (ret);
113 		}
114 
115 		zui.zui_data = data;
116 	} else {
117 		int ret;
118 
119 		ret = amdzen_c_df_read64(dfno, zui.zui_inst, def,
120 		    &zui.zui_data);
121 		if (ret != 0) {
122 			return (ret);
123 		}
124 	}
125 
126 	if (ddi_copyout(&zui, (void *)arg, sizeof (zui), mode & FKIOCTL) != 0) {
127 		return (EFAULT);
128 	}
129 
130 	return (0);
131 }
132 
133 static int
134 zen_udf_close(dev_t dev, int flag, int otyp, cred_t *credp)
135 {
136 	return (0);
137 }
138 
139 static void
140 zen_udf_cleanup(zen_udf_t *zen_udf)
141 {
142 	ddi_remove_minor_node(zen_udf->zudf_dip, NULL);
143 	zen_udf->zudf_ndfs = 0;
144 	zen_udf->zudf_dip = NULL;
145 }
146 
147 static int
148 zen_udf_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
149 {
150 	zen_udf_t *zen_udf = &zen_udf_data;
151 
152 	if (cmd == DDI_RESUME) {
153 		return (DDI_SUCCESS);
154 	} else if (cmd != DDI_ATTACH) {
155 		return (DDI_FAILURE);
156 	}
157 
158 	if (zen_udf->zudf_dip != NULL) {
159 		dev_err(dip, CE_WARN, "!zen_udf is already attached to a "
160 		    "dev_info_t: %p", zen_udf->zudf_dip);
161 		return (DDI_FAILURE);
162 	}
163 
164 	zen_udf->zudf_dip = dip;
165 	zen_udf->zudf_ndfs = amdzen_c_df_count();
166 	for (uint_t i = 0; i < zen_udf->zudf_ndfs; i++) {
167 		char buf[32];
168 
169 		(void) snprintf(buf, sizeof (buf), "zen_udf.%u", i);
170 		if (ddi_create_minor_node(dip, buf, S_IFCHR, i, DDI_PSEUDO,
171 		    0) != DDI_SUCCESS) {
172 			dev_err(dip, CE_WARN, "!failed to create minor %s",
173 			    buf);
174 			goto err;
175 		}
176 	}
177 
178 	return (DDI_SUCCESS);
179 
180 err:
181 	zen_udf_cleanup(zen_udf);
182 	return (DDI_FAILURE);
183 }
184 
185 static int
186 zen_udf_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg, void **resultp)
187 {
188 	zen_udf_t *zen_udf = &zen_udf_data;
189 	minor_t m;
190 
191 	switch (cmd) {
192 	case DDI_INFO_DEVT2DEVINFO:
193 		m = getminor((dev_t)arg);
194 		if (m >= zen_udf->zudf_ndfs) {
195 			return (DDI_FAILURE);
196 		}
197 		*resultp = (void *)zen_udf->zudf_dip;
198 		break;
199 	case DDI_INFO_DEVT2INSTANCE:
200 		m = getminor((dev_t)arg);
201 		if (m >= zen_udf->zudf_ndfs) {
202 			return (DDI_FAILURE);
203 		}
204 		*resultp = (void *)(uintptr_t)ddi_get_instance(
205 		    zen_udf->zudf_dip);
206 		break;
207 	default:
208 		return (DDI_FAILURE);
209 	}
210 	return (DDI_SUCCESS);
211 }
212 
213 static int
214 zen_udf_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
215 {
216 	zen_udf_t *zen_udf = &zen_udf_data;
217 
218 	if (cmd == DDI_SUSPEND) {
219 		return (DDI_SUCCESS);
220 	} else if (cmd != DDI_DETACH) {
221 		return (DDI_FAILURE);
222 	}
223 
224 	if (zen_udf->zudf_dip != dip) {
225 		dev_err(dip, CE_WARN, "!asked to detach zen_udf, but dip "
226 		    "doesn't match");
227 		return (DDI_FAILURE);
228 	}
229 
230 	zen_udf_cleanup(zen_udf);
231 	return (DDI_SUCCESS);
232 }
233 
234 static struct cb_ops zen_udf_cb_ops = {
235 	.cb_open = zen_udf_open,
236 	.cb_close = zen_udf_close,
237 	.cb_strategy = nodev,
238 	.cb_print = nodev,
239 	.cb_dump = nodev,
240 	.cb_read = nodev,
241 	.cb_write = nodev,
242 	.cb_ioctl = zen_udf_ioctl,
243 	.cb_devmap = nodev,
244 	.cb_mmap = nodev,
245 	.cb_segmap = nodev,
246 	.cb_chpoll = nochpoll,
247 	.cb_prop_op = ddi_prop_op,
248 	.cb_flag = D_MP,
249 	.cb_rev = CB_REV,
250 	.cb_aread = nodev,
251 	.cb_awrite = nodev
252 };
253 
254 static struct dev_ops zen_udf_dev_ops = {
255 	.devo_rev = DEVO_REV,
256 	.devo_refcnt = 0,
257 	.devo_getinfo = zen_udf_getinfo,
258 	.devo_identify = nulldev,
259 	.devo_probe = nulldev,
260 	.devo_attach = zen_udf_attach,
261 	.devo_detach = zen_udf_detach,
262 	.devo_reset = nodev,
263 	.devo_quiesce = ddi_quiesce_not_needed,
264 	.devo_cb_ops = &zen_udf_cb_ops
265 };
266 
267 static struct modldrv zen_udf_modldrv = {
268 	.drv_modops = &mod_driverops,
269 	.drv_linkinfo = "AMD User DF Access",
270 	.drv_dev_ops = &zen_udf_dev_ops
271 };
272 
273 static struct modlinkage zen_udf_modlinkage = {
274 	.ml_rev = MODREV_1,
275 	.ml_linkage = { &zen_udf_modldrv, NULL }
276 };
277 
278 int
279 _init(void)
280 {
281 	return (mod_install(&zen_udf_modlinkage));
282 }
283 
284 int
285 _info(struct modinfo *modinfop)
286 {
287 	return (mod_info(&zen_udf_modlinkage, modinfop));
288 }
289 
290 int
291 _fini(void)
292 {
293 	return (mod_remove(&zen_udf_modlinkage));
294 }
295