xref: /freebsd/sys/amd64/amd64/mem.c (revision 87569f75a91f298c52a71823c04d41cf53c88889)
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/ioccom.h>
50  #include <sys/kernel.h>
51  #include <sys/lock.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/signalvar.h>
58  #include <sys/systm.h>
59  #include <sys/uio.h>
60  
61  #include <machine/specialreg.h>
62  #include <machine/vmparam.h>
63  
64  #include <vm/vm.h>
65  #include <vm/pmap.h>
66  #include <vm/vm_extern.h>
67  
68  #include <machine/memdev.h>
69  
70  /* ARGSUSED */
71  int
72  memrw(struct cdev *dev, struct uio *uio, int flags)
73  {
74  	int o;
75  	u_long c = 0, v;
76  	struct iovec *iov;
77  	int error = 0;
78  	vm_offset_t addr, eaddr;
79  
80  	GIANT_REQUIRED;
81  
82  	while (uio->uio_resid > 0 && error == 0) {
83  		iov = uio->uio_iov;
84  		if (iov->iov_len == 0) {
85  			uio->uio_iov++;
86  			uio->uio_iovcnt--;
87  			if (uio->uio_iovcnt < 0)
88  				panic("memrw");
89  			continue;
90  		}
91  		if (minor(dev) == CDEV_MINOR_MEM) {
92  			v = uio->uio_offset;
93  kmemphys:
94  			o = v & PAGE_MASK;
95  			c = min(uio->uio_resid, (u_int)(PAGE_SIZE - o));
96  			error = uiomove((void *)PHYS_TO_DMAP(v), (int)c, uio);
97  			continue;
98  		}
99  		else if (minor(dev) == CDEV_MINOR_KMEM) {
100  			v = uio->uio_offset;
101  
102  			if (v >= DMAP_MIN_ADDRESS && v < DMAP_MAX_ADDRESS) {
103  				v = DMAP_TO_PHYS(v);
104  				goto kmemphys;
105  			}
106  
107  			c = iov->iov_len;
108  
109  			/*
110  			 * Make sure that all of the pages are currently
111  			 * resident so that we don't create any zero-fill
112  			 * pages.
113  			 */
114  			addr = trunc_page(v);
115  			eaddr = round_page(v + c);
116  
117  			if (addr < (vm_offset_t)KERNBASE)
118  				return (EFAULT);
119  			for (; addr < eaddr; addr += PAGE_SIZE)
120  				if (pmap_extract(kernel_pmap, addr) == 0)
121  					return (EFAULT);
122  
123  			if (!kernacc((caddr_t)(long)v, c,
124  			    uio->uio_rw == UIO_READ ?
125  			    VM_PROT_READ : VM_PROT_WRITE))
126  				return (EFAULT);
127  
128  			error = uiomove((caddr_t)(long)v, (int)c, uio);
129  			continue;
130  		}
131  		/* else panic! */
132  	}
133  	return (error);
134  }
135  
136  /*
137   * allow user processes to MMAP some memory sections
138   * instead of going through read/write
139   */
140  /* ARGSUSED */
141  int
142  memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr,
143      int prot __unused)
144  {
145  	if (minor(dev) == CDEV_MINOR_MEM)
146  		*paddr = offset;
147  	else if (minor(dev) == CDEV_MINOR_KMEM)
148          	*paddr = vtophys(offset);
149  	/* else panic! */
150  	return (0);
151  }
152  
153  /*
154   * Operations for changing memory attributes.
155   *
156   * This is basically just an ioctl shim for mem_range_attr_get
157   * and mem_range_attr_set.
158   */
159  /* ARGSUSED */
160  int
161  memioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, int flags,
162      struct thread *td)
163  {
164  	int nd, error = 0;
165  	struct mem_range_op *mo = (struct mem_range_op *)data;
166  	struct mem_range_desc *md;
167  
168  	/* is this for us? */
169  	if ((cmd != MEMRANGE_GET) &&
170  	    (cmd != MEMRANGE_SET))
171  		return (ENOTTY);
172  
173  	/* any chance we can handle this? */
174  	if (mem_range_softc.mr_op == NULL)
175  		return (EOPNOTSUPP);
176  
177  	/* do we have any descriptors? */
178  	if (mem_range_softc.mr_ndesc == 0)
179  		return (ENXIO);
180  
181  	switch (cmd) {
182  	case MEMRANGE_GET:
183  		nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
184  		if (nd > 0) {
185  			md = (struct mem_range_desc *)
186  				malloc(nd * sizeof(struct mem_range_desc),
187  				       M_MEMDESC, M_WAITOK);
188  			error = mem_range_attr_get(md, &nd);
189  			if (!error)
190  				error = copyout(md, mo->mo_desc,
191  					nd * sizeof(struct mem_range_desc));
192  			free(md, M_MEMDESC);
193  		}
194  		else
195  			nd = mem_range_softc.mr_ndesc;
196  		mo->mo_arg[0] = nd;
197  		break;
198  
199  	case MEMRANGE_SET:
200  		md = (struct mem_range_desc *)malloc(sizeof(struct mem_range_desc),
201  						    M_MEMDESC, M_WAITOK);
202  		error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
203  		/* clamp description string */
204  		md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
205  		if (error == 0)
206  			error = mem_range_attr_set(md, &mo->mo_arg[0]);
207  		free(md, M_MEMDESC);
208  		break;
209  	}
210  	return (error);
211  }
212  
213  void
214  dev_mem_md_init(void)
215  {
216  	if (mem_range_softc.mr_op != NULL)
217  		mem_range_softc.mr_op->init(&mem_range_softc);
218  }
219