xref: /freebsd/sys/powerpc/powerpc/mem.c (revision aa0a1e58)
1 /*-
2  * Copyright (c) 1988 University of Utah.
3  * Copyright (c) 1982, 1986, 1990 The Regents of the University of California.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * the Systems Programming Group of the University of Utah Computer
8  * Science Department, and code derived from software contributed to
9  * Berkeley by William Jolitz.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	from: Utah $Hdr: mem.c 1.13 89/10/08$
36  *	from: @(#)mem.c	7.2 (Berkeley) 5/9/91
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 /*
43  * Memory special file
44  */
45 
46 #include <sys/param.h>
47 #include <sys/conf.h>
48 #include <sys/fcntl.h>
49 #include <sys/kernel.h>
50 #include <sys/lock.h>
51 #include <sys/ioccom.h>
52 #include <sys/malloc.h>
53 #include <sys/memrange.h>
54 #include <sys/module.h>
55 #include <sys/mutex.h>
56 #include <sys/proc.h>
57 #include <sys/msgbuf.h>
58 #include <sys/systm.h>
59 #include <sys/signalvar.h>
60 #include <sys/uio.h>
61 
62 #include <machine/md_var.h>
63 #include <machine/vmparam.h>
64 
65 #include <vm/vm.h>
66 #include <vm/pmap.h>
67 #include <vm/vm_extern.h>
68 #include <vm/vm_page.h>
69 
70 #include <machine/memdev.h>
71 
72 static void ppc_mrinit(struct mem_range_softc *);
73 static int ppc_mrset(struct mem_range_softc *, struct mem_range_desc *, int *);
74 
75 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
76 
77 static struct mem_range_ops ppc_mem_range_ops = {
78 	ppc_mrinit,
79 	ppc_mrset,
80 	NULL,
81 	NULL
82 };
83 struct mem_range_softc mem_range_softc = {
84 	&ppc_mem_range_ops,
85 	0, 0, NULL
86 };
87 
88 /* ARGSUSED */
89 int
90 memrw(struct cdev *dev, struct uio *uio, int flags)
91 {
92 	struct iovec *iov;
93 	int error = 0;
94 	vm_offset_t va, eva, off, v;
95 	vm_prot_t prot;
96 	struct vm_page m;
97 	vm_page_t marr;
98 	vm_size_t cnt;
99 
100 	cnt = 0;
101 	error = 0;
102 
103 	GIANT_REQUIRED;
104 
105 	while (uio->uio_resid > 0 && !error) {
106 		iov = uio->uio_iov;
107 		if (iov->iov_len == 0) {
108 			uio->uio_iov++;
109 			uio->uio_iovcnt--;
110 			if (uio->uio_iovcnt < 0)
111 				panic("memrw");
112 			continue;
113 		}
114 		if (dev2unit(dev) == CDEV_MINOR_MEM) {
115 kmem_direct_mapped:	v = uio->uio_offset;
116 
117 			off = uio->uio_offset & PAGE_MASK;
118 			cnt = PAGE_SIZE - ((vm_offset_t)iov->iov_base &
119 			    PAGE_MASK);
120 			cnt = min(cnt, PAGE_SIZE - off);
121 			cnt = min(cnt, iov->iov_len);
122 
123 			if (mem_valid(v, cnt)) {
124 				error = EFAULT;
125 				break;
126 			}
127 
128 			if (!pmap_dev_direct_mapped(v, cnt)) {
129 				error = uiomove((void *)v, cnt, uio);
130 			} else {
131 				m.phys_addr = trunc_page(v);
132 				marr = &m;
133 				error = uiomove_fromphys(&marr, off, cnt, uio);
134 			}
135 		}
136 		else if (dev2unit(dev) == CDEV_MINOR_KMEM) {
137 			va = uio->uio_offset;
138 
139 			if ((va < VM_MIN_KERNEL_ADDRESS) || (va > virtual_end))
140 				goto kmem_direct_mapped;
141 
142 			va = trunc_page(uio->uio_offset);
143 			eva = round_page(uio->uio_offset
144 			    + iov->iov_len);
145 
146 			/*
147 			 * Make sure that all the pages are currently resident
148 			 * so that we don't create any zero-fill pages.
149 			 */
150 
151 			for (; va < eva; va += PAGE_SIZE)
152 				if (pmap_extract(kernel_pmap, va) == 0)
153 					return (EFAULT);
154 
155 			prot = (uio->uio_rw == UIO_READ)
156 			    ? VM_PROT_READ : VM_PROT_WRITE;
157 
158 			va = uio->uio_offset;
159 			if (kernacc((void *) va, iov->iov_len, prot)
160 			    == FALSE)
161 				return (EFAULT);
162 
163 			error = uiomove((void *)va, iov->iov_len, uio);
164 
165 			continue;
166 		}
167 	}
168 
169 	return (error);
170 }
171 
172 /*
173  * allow user processes to MMAP some memory sections
174  * instead of going through read/write
175  */
176 int
177 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
178     int prot, vm_memattr_t *memattr)
179 {
180 	int i;
181 
182 	/*
183 	 * /dev/mem is the only one that makes sense through this
184 	 * interface.  For /dev/kmem any physaddr we return here
185 	 * could be transient and hence incorrect or invalid at
186 	 * a later time.
187 	 */
188 	if (dev2unit(dev) != CDEV_MINOR_MEM)
189 		return (-1);
190 
191 	/* Only direct-mapped addresses. */
192 	if (mem_valid(offset, 0)
193 	    && pmap_dev_direct_mapped(offset, 0))
194 		return (EFAULT);
195 
196 	*paddr = offset;
197 
198 	for (i = 0; i < mem_range_softc.mr_ndesc; i++) {
199 		if (!(mem_range_softc.mr_desc[i].mr_flags & MDF_ACTIVE))
200 			continue;
201 
202 		if (offset >= mem_range_softc.mr_desc[i].mr_base &&
203 		    offset < mem_range_softc.mr_desc[i].mr_base +
204 		    mem_range_softc.mr_desc[i].mr_len) {
205 			switch (mem_range_softc.mr_desc[i].mr_flags &
206 			    MDF_ATTRMASK) {
207 			case MDF_WRITEBACK:
208 				*memattr = VM_MEMATTR_WRITE_BACK;
209 				break;
210 			case MDF_WRITECOMBINE:
211 				*memattr = VM_MEMATTR_WRITE_COMBINING;
212 				break;
213 			case MDF_UNCACHEABLE:
214 				*memattr = VM_MEMATTR_UNCACHEABLE;
215 				break;
216 			case MDF_WRITETHROUGH:
217 				*memattr = VM_MEMATTR_WRITE_THROUGH;
218 				break;
219 			}
220 
221 			break;
222 		}
223 	}
224 
225 	return (0);
226 }
227 
228 static void
229 ppc_mrinit(struct mem_range_softc *sc)
230 {
231 	sc->mr_cap = 0;
232 	sc->mr_ndesc = 8; /* XXX: Should be dynamically expandable */
233 	sc->mr_desc = malloc(sc->mr_ndesc * sizeof(struct mem_range_desc),
234 	    M_MEMDESC, M_NOWAIT | M_ZERO);
235 	if (sc->mr_desc == NULL)
236 		panic("%s: malloc returns NULL", __func__);
237 }
238 
239 static int
240 ppc_mrset(struct mem_range_softc *sc, struct mem_range_desc *desc, int *arg)
241 {
242 	int i;
243 
244 	switch(*arg) {
245 	case MEMRANGE_SET_UPDATE:
246 		for (i = 0; i < sc->mr_ndesc; i++) {
247 			if (!sc->mr_desc[i].mr_len) {
248 				sc->mr_desc[i] = *desc;
249 				sc->mr_desc[i].mr_flags |= MDF_ACTIVE;
250 				return (0);
251 			}
252 			if (sc->mr_desc[i].mr_base == desc->mr_base &&
253 			    sc->mr_desc[i].mr_len == desc->mr_len)
254 				return (EEXIST);
255 		}
256 		return (ENOSPC);
257 	case MEMRANGE_SET_REMOVE:
258 		for (i = 0; i < sc->mr_ndesc; i++)
259 			if (sc->mr_desc[i].mr_base == desc->mr_base &&
260 			    sc->mr_desc[i].mr_len == desc->mr_len) {
261 				bzero(&sc->mr_desc[i], sizeof(sc->mr_desc[i]));
262 				return (0);
263 			}
264 		return (ENOENT);
265 	default:
266 		return (EOPNOTSUPP);
267 	}
268 
269 	return (0);
270 }
271 
272 /*
273  * Operations for changing memory attributes.
274  *
275  * This is basically just an ioctl shim for mem_range_attr_get
276  * and mem_range_attr_set.
277  */
278 /* ARGSUSED */
279 int
280 memioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, int flags,
281     struct thread *td)
282 {
283 	int nd, error = 0;
284 	struct mem_range_op *mo = (struct mem_range_op *)data;
285 	struct mem_range_desc *md;
286 
287 	/* is this for us? */
288 	if ((cmd != MEMRANGE_GET) &&
289 	    (cmd != MEMRANGE_SET))
290 		return (ENOTTY);
291 
292 	/* any chance we can handle this? */
293 	if (mem_range_softc.mr_op == NULL)
294 		return (EOPNOTSUPP);
295 
296 	/* do we have any descriptors? */
297 	if (mem_range_softc.mr_ndesc == 0)
298 		return (ENXIO);
299 
300 	switch (cmd) {
301 	case MEMRANGE_GET:
302 		nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
303 		if (nd > 0) {
304 			md = (struct mem_range_desc *)
305 				malloc(nd * sizeof(struct mem_range_desc),
306 				       M_MEMDESC, M_WAITOK);
307 			error = mem_range_attr_get(md, &nd);
308 			if (!error)
309 				error = copyout(md, mo->mo_desc,
310 					nd * sizeof(struct mem_range_desc));
311 			free(md, M_MEMDESC);
312 		}
313 		else
314 			nd = mem_range_softc.mr_ndesc;
315 		mo->mo_arg[0] = nd;
316 		break;
317 
318 	case MEMRANGE_SET:
319 		md = (struct mem_range_desc *)malloc(sizeof(struct mem_range_desc),
320 						    M_MEMDESC, M_WAITOK);
321 		error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
322 		/* clamp description string */
323 		md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
324 		if (error == 0)
325 			error = mem_range_attr_set(md, &mo->mo_arg[0]);
326 		free(md, M_MEMDESC);
327 		break;
328 	}
329 	return (error);
330 }
331