xref: /freebsd/sys/amd64/vmm/vmm_mem.c (revision d9a447559bc04121f7c6682e64abe67efa154864)
1 /*-
2  * Copyright (c) 2011 NetApp, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/lock.h>
34 #include <sys/mutex.h>
35 #include <sys/linker.h>
36 #include <sys/systm.h>
37 #include <sys/malloc.h>
38 #include <sys/kernel.h>
39 #include <sys/sysctl.h>
40 
41 #include <vm/vm.h>
42 #include <vm/pmap.h>
43 #include <vm/vm_page.h>
44 #include <vm/vm_pageout.h>
45 
46 #include <machine/md_var.h>
47 #include <machine/metadata.h>
48 #include <machine/pc/bios.h>
49 #include <machine/vmparam.h>
50 #include <machine/pmap.h>
51 
52 #include "vmm_util.h"
53 #include "vmm_mem.h"
54 
55 SYSCTL_DECL(_hw_vmm);
56 
57 static u_long pages_allocated;
58 SYSCTL_ULONG(_hw_vmm, OID_AUTO, pages_allocated, CTLFLAG_RD,
59 	     &pages_allocated, 0, "4KB pages allocated");
60 
61 static void
62 update_pages_allocated(int howmany)
63 {
64 	pages_allocated += howmany;	/* XXX locking? */
65 }
66 
67 int
68 vmm_mem_init(void)
69 {
70 
71 	return (0);
72 }
73 
74 vm_paddr_t
75 vmm_mem_alloc(size_t size)
76 {
77 	int flags;
78 	vm_page_t m;
79 	vm_paddr_t pa;
80 
81 	if (size != PAGE_SIZE)
82 		panic("vmm_mem_alloc: invalid allocation size %lu", size);
83 
84 	flags = VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED |
85 		VM_ALLOC_ZERO;
86 
87 	while (1) {
88 		/*
89 		 * XXX need policy to determine when to back off the allocation
90 		 */
91 		m = vm_page_alloc(NULL, 0, flags);
92 		if (m == NULL)
93 			VM_WAIT;
94 		else
95 			break;
96 	}
97 
98 	pa = VM_PAGE_TO_PHYS(m);
99 
100 	if ((m->flags & PG_ZERO) == 0)
101 		pagezero((void *)PHYS_TO_DMAP(pa));
102 	m->valid = VM_PAGE_BITS_ALL;
103 
104 	update_pages_allocated(1);
105 
106 	return (pa);
107 }
108 
109 void
110 vmm_mem_free(vm_paddr_t base, size_t length)
111 {
112 	vm_page_t m;
113 
114 	if (base & PAGE_MASK) {
115 		panic("vmm_mem_free: base 0x%0lx must be aligned on a "
116 		      "0x%0x boundary\n", base, PAGE_SIZE);
117 	}
118 
119 	if (length != PAGE_SIZE)
120 		panic("vmm_mem_free: invalid length %lu", length);
121 
122 	m = PHYS_TO_VM_PAGE(base);
123 	m->wire_count--;
124 	vm_page_free(m);
125 	atomic_subtract_int(&cnt.v_wire_count, 1);
126 
127 	update_pages_allocated(-1);
128 }
129 
130 vm_paddr_t
131 vmm_mem_maxaddr(void)
132 {
133 
134 	return (ptoa(Maxmem));
135 }
136