xref: /freebsd/sys/powerpc/powerpc/mem.c (revision c697fb7f)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1988 University of Utah.
5  * Copyright (c) 1982, 1986, 1990 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * the Systems Programming Group of the University of Utah Computer
10  * Science Department, and code derived from software contributed to
11  * Berkeley by William Jolitz.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  *	from: Utah $Hdr: mem.c 1.13 89/10/08$
38  *	from: @(#)mem.c	7.2 (Berkeley) 5/9/91
39  */
40 
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 /*
45  * Memory special file
46  */
47 
48 #include <sys/param.h>
49 #include <sys/conf.h>
50 #include <sys/fcntl.h>
51 #include <sys/kernel.h>
52 #include <sys/lock.h>
53 #include <sys/ioccom.h>
54 #include <sys/malloc.h>
55 #include <sys/memrange.h>
56 #include <sys/module.h>
57 #include <sys/mutex.h>
58 #include <sys/proc.h>
59 #include <sys/msgbuf.h>
60 #include <sys/systm.h>
61 #include <sys/signalvar.h>
62 #include <sys/uio.h>
63 
64 #include <machine/md_var.h>
65 #include <machine/vmparam.h>
66 
67 #include <vm/vm.h>
68 #include <vm/pmap.h>
69 #include <vm/vm_extern.h>
70 #include <vm/vm_page.h>
71 
72 #include <machine/memdev.h>
73 
74 static void ppc_mrinit(struct mem_range_softc *);
75 static int ppc_mrset(struct mem_range_softc *, struct mem_range_desc *, int *);
76 
77 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
78 
79 static struct mem_range_ops ppc_mem_range_ops = {
80 	ppc_mrinit,
81 	ppc_mrset,
82 	NULL,
83 	NULL
84 };
85 struct mem_range_softc mem_range_softc = {
86 	&ppc_mem_range_ops,
87 	0, 0, NULL
88 };
89 
90 /* ARGSUSED */
91 int
92 memrw(struct cdev *dev, struct uio *uio, int flags)
93 {
94 	struct iovec *iov;
95 	int error = 0;
96 	vm_offset_t va, eva, off, v;
97 	vm_prot_t prot;
98 	struct vm_page m;
99 	vm_page_t marr;
100 	vm_size_t cnt;
101 	ssize_t orig_resid;
102 
103 	cnt = 0;
104 	error = 0;
105 	orig_resid = uio->uio_resid;
106 
107 	while (uio->uio_resid > 0 && !error) {
108 		iov = uio->uio_iov;
109 		if (iov->iov_len == 0) {
110 			uio->uio_iov++;
111 			uio->uio_iovcnt--;
112 			if (uio->uio_iovcnt < 0)
113 				panic("memrw");
114 			continue;
115 		}
116 		if (dev2unit(dev) == CDEV_MINOR_MEM) {
117 			v = uio->uio_offset;
118 
119 kmem_direct_mapped:	off = v & PAGE_MASK;
120 			cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base &
121 			    PAGE_MASK);
122 			cnt = min(cnt, PAGE_SIZE - off);
123 			cnt = min(cnt, iov->iov_len);
124 
125 			if (mem_valid(v, cnt)) {
126 				error = EFAULT;
127 				break;
128 			}
129 
130 			if (hw_direct_map && !pmap_dev_direct_mapped(v, cnt)) {
131 				error = uiomove((void *)PHYS_TO_DMAP(v), cnt,
132 				    uio);
133 			} else {
134 				m.phys_addr = trunc_page(v);
135 				marr = &m;
136 				error = uiomove_fromphys(&marr, off, cnt, uio);
137 			}
138 		}
139 		else if (dev2unit(dev) == CDEV_MINOR_KMEM) {
140 			va = uio->uio_offset;
141 
142 			if (hw_direct_map &&
143 			    ((va < VM_MIN_KERNEL_ADDRESS) || (va > virtual_end))) {
144 				v = DMAP_TO_PHYS(va);
145 				goto kmem_direct_mapped;
146 			}
147 
148 			va = trunc_page(uio->uio_offset);
149 			eva = round_page(uio->uio_offset
150 			    + iov->iov_len);
151 
152 			/*
153 			 * Make sure that all the pages are currently resident
154 			 * so that we don't create any zero-fill pages.
155 			 */
156 
157 			for (; va < eva; va += PAGE_SIZE) {
158 				if (pmap_extract(kernel_pmap, va) == 0) {
159 					error = EFAULT;
160 					break;
161 				}
162 			}
163 			if (error != 0)
164 				break;
165 
166 			prot = (uio->uio_rw == UIO_READ)
167 			    ? VM_PROT_READ : VM_PROT_WRITE;
168 
169 			va = uio->uio_offset;
170 			if (((va >= VM_MIN_KERNEL_ADDRESS) && (va <= virtual_end)) &&
171 			    !kernacc((void *) va, iov->iov_len, prot)) {
172 				error = EFAULT;
173 				break;
174 			}
175 
176 			error = uiomove((void *)va, iov->iov_len, uio);
177 		}
178 	}
179 	/*
180 	 * Don't return error if any byte was written.  Read and write
181 	 * can return error only if no i/o was performed.
182 	 */
183 	if (uio->uio_resid != orig_resid)
184 		error = 0;
185 	return (error);
186 }
187 
188 /*
189  * allow user processes to MMAP some memory sections
190  * instead of going through read/write
191  */
192 int
193 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
194     int prot, vm_memattr_t *memattr)
195 {
196 	int i;
197 
198 	if (dev2unit(dev) == CDEV_MINOR_MEM)
199 		*paddr = offset;
200 	else
201 		return (EFAULT);
202 
203 	for (i = 0; i < mem_range_softc.mr_ndesc; i++) {
204 		if (!(mem_range_softc.mr_desc[i].mr_flags & MDF_ACTIVE))
205 			continue;
206 
207 		if (offset >= mem_range_softc.mr_desc[i].mr_base &&
208 		    offset < mem_range_softc.mr_desc[i].mr_base +
209 		    mem_range_softc.mr_desc[i].mr_len) {
210 			switch (mem_range_softc.mr_desc[i].mr_flags &
211 			    MDF_ATTRMASK) {
212 			case MDF_WRITEBACK:
213 				*memattr = VM_MEMATTR_WRITE_BACK;
214 				break;
215 			case MDF_WRITECOMBINE:
216 				*memattr = VM_MEMATTR_WRITE_COMBINING;
217 				break;
218 			case MDF_UNCACHEABLE:
219 				*memattr = VM_MEMATTR_UNCACHEABLE;
220 				break;
221 			case MDF_WRITETHROUGH:
222 				*memattr = VM_MEMATTR_WRITE_THROUGH;
223 				break;
224 			}
225 
226 			break;
227 		}
228 	}
229 
230 	return (0);
231 }
232 
233 static void
234 ppc_mrinit(struct mem_range_softc *sc)
235 {
236 	sc->mr_cap = 0;
237 	sc->mr_ndesc = 8; /* XXX: Should be dynamically expandable */
238 	sc->mr_desc = malloc(sc->mr_ndesc * sizeof(struct mem_range_desc),
239 	    M_MEMDESC, M_WAITOK | M_ZERO);
240 }
241 
242 static int
243 ppc_mrset(struct mem_range_softc *sc, struct mem_range_desc *desc, int *arg)
244 {
245 	int i;
246 
247 	switch(*arg) {
248 	case MEMRANGE_SET_UPDATE:
249 		for (i = 0; i < sc->mr_ndesc; i++) {
250 			if (!sc->mr_desc[i].mr_len) {
251 				sc->mr_desc[i] = *desc;
252 				sc->mr_desc[i].mr_flags |= MDF_ACTIVE;
253 				return (0);
254 			}
255 			if (sc->mr_desc[i].mr_base == desc->mr_base &&
256 			    sc->mr_desc[i].mr_len == desc->mr_len)
257 				return (EEXIST);
258 		}
259 		return (ENOSPC);
260 	case MEMRANGE_SET_REMOVE:
261 		for (i = 0; i < sc->mr_ndesc; i++)
262 			if (sc->mr_desc[i].mr_base == desc->mr_base &&
263 			    sc->mr_desc[i].mr_len == desc->mr_len) {
264 				bzero(&sc->mr_desc[i], sizeof(sc->mr_desc[i]));
265 				return (0);
266 			}
267 		return (ENOENT);
268 	default:
269 		return (EOPNOTSUPP);
270 	}
271 
272 	return (0);
273 }
274 
275 /*
276  * Operations for changing memory attributes.
277  *
278  * This is basically just an ioctl shim for mem_range_attr_get
279  * and mem_range_attr_set.
280  */
281 /* ARGSUSED */
282 int
283 memioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, int flags,
284     struct thread *td)
285 {
286 	int nd, error = 0;
287 	struct mem_range_op *mo = (struct mem_range_op *)data;
288 	struct mem_range_desc *md;
289 
290 	/* is this for us? */
291 	if ((cmd != MEMRANGE_GET) &&
292 	    (cmd != MEMRANGE_SET))
293 		return (ENOTTY);
294 
295 	/* any chance we can handle this? */
296 	if (mem_range_softc.mr_op == NULL)
297 		return (EOPNOTSUPP);
298 
299 	/* do we have any descriptors? */
300 	if (mem_range_softc.mr_ndesc == 0)
301 		return (ENXIO);
302 
303 	switch (cmd) {
304 	case MEMRANGE_GET:
305 		nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
306 		if (nd > 0) {
307 			md = (struct mem_range_desc *)
308 				malloc(nd * sizeof(struct mem_range_desc),
309 				       M_MEMDESC, M_WAITOK);
310 			error = mem_range_attr_get(md, &nd);
311 			if (!error)
312 				error = copyout(md, mo->mo_desc,
313 					nd * sizeof(struct mem_range_desc));
314 			free(md, M_MEMDESC);
315 		}
316 		else
317 			nd = mem_range_softc.mr_ndesc;
318 		mo->mo_arg[0] = nd;
319 		break;
320 
321 	case MEMRANGE_SET:
322 		md = (struct mem_range_desc *)malloc(sizeof(struct mem_range_desc),
323 						    M_MEMDESC, M_WAITOK);
324 		error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
325 		/* clamp description string */
326 		md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
327 		if (error == 0)
328 			error = mem_range_attr_set(md, &mo->mo_arg[0]);
329 		free(md, M_MEMDESC);
330 		break;
331 	}
332 	return (error);
333 }
334 
335