xref: /netbsd-src/sys/miscfs/procfs/procfs_map.c (revision cf63a6b052194ad67336cf0ca9e74806eddd6bfa)
1 /*	$NetBSD: procfs_map.c,v 1.14 2001/11/06 07:20:37 simonb Exp $	*/
2 
3 /*
4  * Copyright (c) 1993 Jan-Simon Pendry
5  * Copyright (c) 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Jan-Simon Pendry.
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  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  *	@(#)procfs_status.c	8.3 (Berkeley) 2/17/94
40  *
41  *	$FreeBSD: procfs_map.c,v 1.18 1998/12/04 22:54:51 archie Exp $
42  */
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/proc.h>
47 #include <sys/vnode.h>
48 #include <sys/malloc.h>
49 #include <sys/namei.h>
50 #include <miscfs/procfs/procfs.h>
51 
52 #include <sys/lock.h>
53 
54 #include <uvm/uvm.h>
55 
56 #define MEBUFFERSIZE 256
57 
58 extern int getcwd_common __P((struct vnode *, struct vnode *,
59 			      char **, char *, int, int, struct proc *));
60 
61 static int procfs_vnode_to_path(struct vnode *vp, char *path, int len,
62 				struct proc *curp, struct proc *p);
63 
64 /*
65  * The map entries can *almost* be read with programs like cat.  However,
66  * large maps need special programs to read.  It is not easy to implement
67  * a program that can sense the required size of the buffer, and then
68  * subsequently do a read with the appropriate size.  This operation cannot
69  * be atomic.  The best that we can do is to allow the program to do a read
70  * with an arbitrarily large buffer, and return as much as we can.  We can
71  * return an error code if the buffer is too small (EFBIG), then the program
72  * can try a bigger buffer.
73  */
74 int
75 procfs_domap(struct proc *curp, struct proc *p, struct pfsnode *pfs,
76 	     struct uio *uio, int linuxmode)
77 {
78 	int len;
79 	int error;
80 	struct vm_map *map = &p->p_vmspace->vm_map;
81 	struct vm_map_entry *entry;
82 	char mebuffer[MEBUFFERSIZE];
83 	char *path;
84 	struct vnode *vp;
85 	struct vattr va;
86 	dev_t dev;
87 	long fileid;
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 != &curproc->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 
102 		if (UVM_ET_ISSUBMAP(entry))
103 			continue;
104 
105 		if (linuxmode != 0) {
106 			path = (char *)malloc(MAXPATHLEN * 4, M_TEMP, M_WAITOK);
107 			if (path == NULL) {
108 				error = ENOMEM;
109 				break;
110 			}
111 			*path = 0;
112 
113 			dev = (dev_t)0;
114 			fileid = 0;
115 			if (UVM_ET_ISOBJ(entry) &&
116 			    UVM_OBJ_IS_VNODE(entry->object.uvm_obj)) {
117 				vp = (struct vnode *)entry->object.uvm_obj;
118 				error = VOP_GETATTR(vp, &va, curp->p_ucred,
119 				    curp);
120 				if (error == 0 && vp != pfs->pfs_vnode) {
121 					fileid = va.va_fileid;
122 					dev = va.va_fsid;
123 					error = procfs_vnode_to_path(vp, path,
124 					    MAXPATHLEN * 4, curp, p);
125 				}
126 			}
127 			snprintf(mebuffer, sizeof(mebuffer),
128 			    "%0*lx-%0*lx %c%c%c%c %0*lx %02x:%02x %ld     %s\n",
129 			    (int)sizeof(void *) * 2,(unsigned long)entry->start,
130 			    (int)sizeof(void *) * 2,(unsigned long)entry->end,
131 			    (entry->protection & VM_PROT_READ) ? 'r' : '-',
132 			    (entry->protection & VM_PROT_WRITE) ? 'w' : '-',
133 			    (entry->protection & VM_PROT_EXECUTE) ? 'x' : '-',
134 			    (entry->etype & UVM_ET_COPYONWRITE) ? 'p' : 's',
135 			    (int)sizeof(void *) * 2,
136 			    (unsigned long)entry->offset,
137 			    major(dev), minor(dev), fileid, path);
138 			free(path, M_TEMP);
139 		} else {
140 			snprintf(mebuffer, sizeof(mebuffer),
141 			    "0x%lx 0x%lx %c%c%c %c%c%c %s %s %d %d %d\n",
142 			    entry->start, entry->end,
143 			    (entry->protection & VM_PROT_READ) ? 'r' : '-',
144 			    (entry->protection & VM_PROT_WRITE) ? 'w' : '-',
145 			    (entry->protection & VM_PROT_EXECUTE) ? 'x' : '-',
146 			    (entry->max_protection & VM_PROT_READ) ? 'r' : '-',
147 			    (entry->max_protection & VM_PROT_WRITE) ? 'w' : '-',
148 			    (entry->max_protection & VM_PROT_EXECUTE) ?
149 				'x' : '-',
150 			    (entry->etype & UVM_ET_COPYONWRITE) ?
151 				"COW" : "NCOW",
152 			    (entry->etype & UVM_ET_NEEDSCOPY) ? "NC" : "NNC",
153 			    entry->inheritance, entry->wired_count,
154 			    entry->advice);
155 		}
156 
157 		len = strlen(mebuffer);
158 		if (len > uio->uio_resid) {
159 			error = EFBIG;
160 			break;
161 		}
162 		error = uiomove(mebuffer, len, uio);
163 		if (error)
164 			break;
165 	}
166 	if (map != &curproc->p_vmspace->vm_map)
167 		vm_map_unlock_read(map);
168 	return error;
169 }
170 
171 int
172 procfs_validmap(struct proc *p, struct mount *mp)
173 {
174 	return ((p->p_flag & P_SYSTEM) == 0);
175 }
176 
177 /*
178  * Try to find a pathname for a vnode. Since there is no mapping
179  * vnode -> parent directory, this needs the NAMECACHE_ENTER_REVERSE
180  * option to work (to make cache_revlookup succeed).
181  */
182 static int procfs_vnode_to_path(struct vnode *vp, char *path, int len,
183 				struct proc *curp, struct proc *p)
184 {
185 	int error, lenused, elen;
186 	char *bp, *bend;
187 	struct vnode *dvp;
188 
189 	bp = bend = &path[len];
190 	*(--bp) = '\0';
191 
192 	error = vget(vp, LK_EXCLUSIVE | LK_RETRY);
193 	if (error != 0)
194 		return error;
195 	error = cache_revlookup(vp, &dvp, &bp, path);
196 	vput(vp);
197 	if (error != 0)
198 		return (error == -1 ? ENOENT : error);
199 
200 	error = vget(dvp, 0);
201 	if (error != 0)
202 		return error;
203 	*(--bp) = '/';
204 	/* XXX GETCWD_CHECK_ACCESS == 0x0001 */
205 	error = getcwd_common(dvp, NULL, &bp, path, len / 2, 1, curp);
206 
207 	/*
208 	 * Strip off emulation path for emulated processes looking at
209 	 * the maps file of a process of the same emulation. (Won't
210 	 * work if /emul/xxx is a symlink..)
211 	 */
212 	if (curp->p_emul == p->p_emul && curp->p_emul->e_path != NULL) {
213 		elen = strlen(curp->p_emul->e_path);
214 		if (!strncmp(bp, curp->p_emul->e_path, elen))
215 			bp = &bp[elen];
216 	}
217 
218 	lenused = bend - bp;
219 
220 	memcpy(path, bp, lenused);
221 	path[lenused] = 0;
222 
223 	return 0;
224 }
225