xref: /illumos-gate/usr/src/uts/intel/io/amdzen/zen_udf.c (revision ce01deb6d39b300af7a4301eebdd545595ae4171)
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 2025 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
zen_udf_open(dev_t * devp,int flags,int otype,cred_t * credp)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
zen_udf_ioctl(dev_t dev,int cmd,intptr_t arg,int mode,cred_t * credp,int * rvalp)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 	boolean_t bcast, do64;
80 
81 	if (cmd != ZEN_UDF_READ) {
82 		return (ENOTTY);
83 	}
84 
85 	dfno = getminor(dev);
86 	if (dfno >= zen_udf->zudf_ndfs) {
87 		return (ENXIO);
88 	}
89 
90 	if (crgetzoneid(credp) != GLOBAL_ZONEID ||
91 	    secpolicy_hwmanip(credp) != 0) {
92 		return (EPERM);
93 	}
94 
95 	if (ddi_copyin((void *)arg, &zui, sizeof (zui), mode & FKIOCTL) != 0) {
96 		return (EFAULT);
97 	}
98 
99 	if ((zui.zui_flags & ~(ZEN_UDF_F_BCAST | ZEN_UDF_F_64)) != 0) {
100 		return (EINVAL);
101 	}
102 
103 	bcast = (zui.zui_flags & ZEN_UDF_F_BCAST) != 0;
104 	do64 = (zui.zui_flags & ZEN_UDF_F_64) != 0;
105 
106 	/*
107 	 * Cons up a register definition based on the user request. We set the
108 	 * gen to our current one.
109 	 */
110 	def.drd_gens = amdzen_c_df_rev();
111 	def.drd_func = zui.zui_func;
112 	def.drd_reg = zui.zui_reg;
113 
114 	if (!do64) {
115 		int ret;
116 		uint32_t data;
117 
118 		ret = bcast ?
119 		    amdzen_c_df_read32_bcast(dfno, def, &data) :
120 		    amdzen_c_df_read32(dfno, zui.zui_inst, def, &data);
121 		if (ret != 0) {
122 			return (ret);
123 		}
124 
125 		zui.zui_data = data;
126 	} else {
127 		int ret;
128 
129 		ret = bcast ?
130 		    amdzen_c_df_read64_bcast(dfno, def, &zui.zui_data) :
131 		    amdzen_c_df_read64(dfno, zui.zui_inst, def, &zui.zui_data);
132 		if (ret != 0) {
133 			return (ret);
134 		}
135 	}
136 
137 	if (ddi_copyout(&zui, (void *)arg, sizeof (zui), mode & FKIOCTL) != 0) {
138 		return (EFAULT);
139 	}
140 
141 	return (0);
142 }
143 
144 static int
zen_udf_close(dev_t dev,int flag,int otyp,cred_t * credp)145 zen_udf_close(dev_t dev, int flag, int otyp, cred_t *credp)
146 {
147 	return (0);
148 }
149 
150 static void
zen_udf_cleanup(zen_udf_t * zen_udf)151 zen_udf_cleanup(zen_udf_t *zen_udf)
152 {
153 	ddi_remove_minor_node(zen_udf->zudf_dip, NULL);
154 	zen_udf->zudf_ndfs = 0;
155 	zen_udf->zudf_dip = NULL;
156 }
157 
158 static int
zen_udf_attach(dev_info_t * dip,ddi_attach_cmd_t cmd)159 zen_udf_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
160 {
161 	zen_udf_t *zen_udf = &zen_udf_data;
162 
163 	if (cmd == DDI_RESUME) {
164 		return (DDI_SUCCESS);
165 	} else if (cmd != DDI_ATTACH) {
166 		return (DDI_FAILURE);
167 	}
168 
169 	if (zen_udf->zudf_dip != NULL) {
170 		dev_err(dip, CE_WARN, "!zen_udf is already attached to a "
171 		    "dev_info_t: %p", zen_udf->zudf_dip);
172 		return (DDI_FAILURE);
173 	}
174 
175 	zen_udf->zudf_dip = dip;
176 	zen_udf->zudf_ndfs = amdzen_c_df_count();
177 	for (uint_t i = 0; i < zen_udf->zudf_ndfs; i++) {
178 		char buf[32];
179 
180 		(void) snprintf(buf, sizeof (buf), "zen_udf.%u", i);
181 		if (ddi_create_minor_node(dip, buf, S_IFCHR, i, DDI_PSEUDO,
182 		    0) != DDI_SUCCESS) {
183 			dev_err(dip, CE_WARN, "!failed to create minor %s",
184 			    buf);
185 			goto err;
186 		}
187 	}
188 
189 	return (DDI_SUCCESS);
190 
191 err:
192 	zen_udf_cleanup(zen_udf);
193 	return (DDI_FAILURE);
194 }
195 
196 static int
zen_udf_getinfo(dev_info_t * dip,ddi_info_cmd_t cmd,void * arg,void ** resultp)197 zen_udf_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg, void **resultp)
198 {
199 	zen_udf_t *zen_udf = &zen_udf_data;
200 	minor_t m;
201 
202 	switch (cmd) {
203 	case DDI_INFO_DEVT2DEVINFO:
204 		m = getminor((dev_t)arg);
205 		if (m >= zen_udf->zudf_ndfs) {
206 			return (DDI_FAILURE);
207 		}
208 		*resultp = (void *)zen_udf->zudf_dip;
209 		break;
210 	case DDI_INFO_DEVT2INSTANCE:
211 		m = getminor((dev_t)arg);
212 		if (m >= zen_udf->zudf_ndfs) {
213 			return (DDI_FAILURE);
214 		}
215 		*resultp = (void *)(uintptr_t)ddi_get_instance(
216 		    zen_udf->zudf_dip);
217 		break;
218 	default:
219 		return (DDI_FAILURE);
220 	}
221 	return (DDI_SUCCESS);
222 }
223 
224 static int
zen_udf_detach(dev_info_t * dip,ddi_detach_cmd_t cmd)225 zen_udf_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
226 {
227 	zen_udf_t *zen_udf = &zen_udf_data;
228 
229 	if (cmd == DDI_SUSPEND) {
230 		return (DDI_SUCCESS);
231 	} else if (cmd != DDI_DETACH) {
232 		return (DDI_FAILURE);
233 	}
234 
235 	if (zen_udf->zudf_dip != dip) {
236 		dev_err(dip, CE_WARN, "!asked to detach zen_udf, but dip "
237 		    "doesn't match");
238 		return (DDI_FAILURE);
239 	}
240 
241 	zen_udf_cleanup(zen_udf);
242 	return (DDI_SUCCESS);
243 }
244 
245 static struct cb_ops zen_udf_cb_ops = {
246 	.cb_open = zen_udf_open,
247 	.cb_close = zen_udf_close,
248 	.cb_strategy = nodev,
249 	.cb_print = nodev,
250 	.cb_dump = nodev,
251 	.cb_read = nodev,
252 	.cb_write = nodev,
253 	.cb_ioctl = zen_udf_ioctl,
254 	.cb_devmap = nodev,
255 	.cb_mmap = nodev,
256 	.cb_segmap = nodev,
257 	.cb_chpoll = nochpoll,
258 	.cb_prop_op = ddi_prop_op,
259 	.cb_flag = D_MP,
260 	.cb_rev = CB_REV,
261 	.cb_aread = nodev,
262 	.cb_awrite = nodev
263 };
264 
265 static struct dev_ops zen_udf_dev_ops = {
266 	.devo_rev = DEVO_REV,
267 	.devo_refcnt = 0,
268 	.devo_getinfo = zen_udf_getinfo,
269 	.devo_identify = nulldev,
270 	.devo_probe = nulldev,
271 	.devo_attach = zen_udf_attach,
272 	.devo_detach = zen_udf_detach,
273 	.devo_reset = nodev,
274 	.devo_quiesce = ddi_quiesce_not_needed,
275 	.devo_cb_ops = &zen_udf_cb_ops
276 };
277 
278 static struct modldrv zen_udf_modldrv = {
279 	.drv_modops = &mod_driverops,
280 	.drv_linkinfo = "AMD User DF Access",
281 	.drv_dev_ops = &zen_udf_dev_ops
282 };
283 
284 static struct modlinkage zen_udf_modlinkage = {
285 	.ml_rev = MODREV_1,
286 	.ml_linkage = { &zen_udf_modldrv, NULL }
287 };
288 
289 int
_init(void)290 _init(void)
291 {
292 	return (mod_install(&zen_udf_modlinkage));
293 }
294 
295 int
_info(struct modinfo * modinfop)296 _info(struct modinfo *modinfop)
297 {
298 	return (mod_info(&zen_udf_modlinkage, modinfop));
299 }
300 
301 int
_fini(void)302 _fini(void)
303 {
304 	return (mod_remove(&zen_udf_modlinkage));
305 }
306