xref: /freebsd/sys/fs/procfs/procfs_map.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
1 /*
2  * Copyright (c) 1993 Jan-Simon Pendry
3  * Copyright (c) 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Jan-Simon Pendry.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. 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  *	@(#)procfs_status.c	8.3 (Berkeley) 2/17/94
38  *
39  * $FreeBSD$
40  */
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/lock.h>
45 #include <sys/mutex.h>
46 #include <sys/proc.h>
47 #include <sys/uio.h>
48 
49 #include <fs/pseudofs/pseudofs.h>
50 #include <fs/procfs/procfs.h>
51 
52 #include <vm/vm.h>
53 #include <vm/pmap.h>
54 #include <vm/vm_map.h>
55 #include <vm/vm_page.h>
56 #include <vm/vm_object.h>
57 
58 
59 #define MEBUFFERSIZE 256
60 
61 /*
62  * The map entries can *almost* be read with programs like cat.  However,
63  * large maps need special programs to read.  It is not easy to implement
64  * a program that can sense the required size of the buffer, and then
65  * subsequently do a read with the appropriate size.  This operation cannot
66  * be atomic.  The best that we can do is to allow the program to do a read
67  * with an arbitrarily large buffer, and return as much as we can.  We can
68  * return an error code if the buffer is too small (EFBIG), then the program
69  * can try a bigger buffer.
70  */
71 int
72 procfs_doprocmap(PFS_FILL_ARGS)
73 {
74 	int len;
75 	int error;
76 	vm_map_t map = &p->p_vmspace->vm_map;
77 	pmap_t pmap = vmspace_pmap(p->p_vmspace);
78 	vm_map_entry_t entry;
79 	char mebuffer[MEBUFFERSIZE];
80 
81 	GIANT_REQUIRED;
82 
83 	PROC_LOCK(p);
84 	error = p_candebug(td, p);
85 	PROC_UNLOCK(p);
86 	if (error)
87 		return (error);
88 
89 	if (uio->uio_rw != UIO_READ)
90 		return (EOPNOTSUPP);
91 
92 	if (uio->uio_offset != 0)
93 		return (0);
94 
95 	error = 0;
96 	if (map != &curthread->td_proc->p_vmspace->vm_map)
97 		vm_map_lock_read(map);
98 	for (entry = map->header.next;
99 		((uio->uio_resid > 0) && (entry != &map->header));
100 		entry = entry->next) {
101 		vm_object_t obj, tobj, lobj;
102 		int ref_count, shadow_count, flags;
103 		vm_offset_t addr;
104 		int resident, privateresident;
105 		char *type;
106 
107 		if (entry->eflags & MAP_ENTRY_IS_SUB_MAP)
108 			continue;
109 
110 		obj = entry->object.vm_object;
111 		if (obj && (obj->shadow_count == 1))
112 			privateresident = obj->resident_page_count;
113 		else
114 			privateresident = 0;
115 
116 		resident = 0;
117 		addr = entry->start;
118 		while (addr < entry->end) {
119 			if (pmap_extract( pmap, addr))
120 				resident++;
121 			addr += PAGE_SIZE;
122 		}
123 
124 		for (lobj = tobj = obj; tobj; tobj = tobj->backing_object)
125 			lobj = tobj;
126 
127 		if (lobj) {
128 			switch(lobj->type) {
129 			default:
130 			case OBJT_DEFAULT:
131 				type = "default";
132 				break;
133 			case OBJT_VNODE:
134 				type = "vnode";
135 				break;
136 			case OBJT_SWAP:
137 				type = "swap";
138 				break;
139 			case OBJT_DEVICE:
140 				type = "device";
141 				break;
142 			}
143 
144 			flags = obj->flags;
145 			ref_count = obj->ref_count;
146 			shadow_count = obj->shadow_count;
147 		} else {
148 			type = "none";
149 			flags = 0;
150 			ref_count = 0;
151 			shadow_count = 0;
152 		}
153 
154 		/*
155 		 * format:
156 		 *  start, end, resident, private resident, cow, access, type.
157 		 */
158 		snprintf(mebuffer, sizeof mebuffer,
159 		    "0x%lx 0x%lx %d %d %p %s%s%s %d %d 0x%x %s %s %s\n",
160 			(u_long)entry->start, (u_long)entry->end,
161 			resident, privateresident, obj,
162 			(entry->protection & VM_PROT_READ)?"r":"-",
163 			(entry->protection & VM_PROT_WRITE)?"w":"-",
164 			(entry->protection & VM_PROT_EXECUTE)?"x":"-",
165 			ref_count, shadow_count, flags,
166 			(entry->eflags & MAP_ENTRY_COW)?"COW":"NCOW",
167 			(entry->eflags & MAP_ENTRY_NEEDS_COPY)?"NC":"NNC",
168 			type);
169 
170 		len = strlen(mebuffer);
171 		if (len > uio->uio_resid) {
172 			error = EFBIG;
173 			break;
174 		}
175 		error = uiomove(mebuffer, len, uio);
176 		if (error)
177 			break;
178 	}
179 	if (map != &curthread->td_proc->p_vmspace->vm_map)
180 		vm_map_unlock_read(map);
181 
182 	return (error);
183 }
184