xref: /netbsd/sys/miscfs/procfs/procfs_map.c (revision bf9ec67e)
1 /*	$NetBSD: procfs_map.c,v 1.15 2001/11/10 13:33:43 lukem 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/cdefs.h>
45 __KERNEL_RCSID(0, "$NetBSD: procfs_map.c,v 1.15 2001/11/10 13:33:43 lukem Exp $");
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/proc.h>
50 #include <sys/vnode.h>
51 #include <sys/malloc.h>
52 #include <sys/namei.h>
53 #include <miscfs/procfs/procfs.h>
54 
55 #include <sys/lock.h>
56 
57 #include <uvm/uvm.h>
58 
59 #define MEBUFFERSIZE 256
60 
61 extern int getcwd_common __P((struct vnode *, struct vnode *,
62 			      char **, char *, int, int, struct proc *));
63 
64 static int procfs_vnode_to_path(struct vnode *vp, char *path, int len,
65 				struct proc *curp, struct proc *p);
66 
67 /*
68  * The map entries can *almost* be read with programs like cat.  However,
69  * large maps need special programs to read.  It is not easy to implement
70  * a program that can sense the required size of the buffer, and then
71  * subsequently do a read with the appropriate size.  This operation cannot
72  * be atomic.  The best that we can do is to allow the program to do a read
73  * with an arbitrarily large buffer, and return as much as we can.  We can
74  * return an error code if the buffer is too small (EFBIG), then the program
75  * can try a bigger buffer.
76  */
77 int
78 procfs_domap(struct proc *curp, struct proc *p, struct pfsnode *pfs,
79 	     struct uio *uio, int linuxmode)
80 {
81 	int len;
82 	int error;
83 	struct vm_map *map = &p->p_vmspace->vm_map;
84 	struct vm_map_entry *entry;
85 	char mebuffer[MEBUFFERSIZE];
86 	char *path;
87 	struct vnode *vp;
88 	struct vattr va;
89 	dev_t dev;
90 	long fileid;
91 
92 	if (uio->uio_rw != UIO_READ)
93 		return (EOPNOTSUPP);
94 
95 	if (uio->uio_offset != 0)
96 		return (0);
97 
98 	error = 0;
99 	if (map != &curproc->p_vmspace->vm_map)
100 		vm_map_lock_read(map);
101 	for (entry = map->header.next;
102 		((uio->uio_resid > 0) && (entry != &map->header));
103 		entry = entry->next) {
104 
105 		if (UVM_ET_ISSUBMAP(entry))
106 			continue;
107 
108 		if (linuxmode != 0) {
109 			path = (char *)malloc(MAXPATHLEN * 4, M_TEMP, M_WAITOK);
110 			if (path == NULL) {
111 				error = ENOMEM;
112 				break;
113 			}
114 			*path = 0;
115 
116 			dev = (dev_t)0;
117 			fileid = 0;
118 			if (UVM_ET_ISOBJ(entry) &&
119 			    UVM_OBJ_IS_VNODE(entry->object.uvm_obj)) {
120 				vp = (struct vnode *)entry->object.uvm_obj;
121 				error = VOP_GETATTR(vp, &va, curp->p_ucred,
122 				    curp);
123 				if (error == 0 && vp != pfs->pfs_vnode) {
124 					fileid = va.va_fileid;
125 					dev = va.va_fsid;
126 					error = procfs_vnode_to_path(vp, path,
127 					    MAXPATHLEN * 4, curp, p);
128 				}
129 			}
130 			snprintf(mebuffer, sizeof(mebuffer),
131 			    "%0*lx-%0*lx %c%c%c%c %0*lx %02x:%02x %ld     %s\n",
132 			    (int)sizeof(void *) * 2,(unsigned long)entry->start,
133 			    (int)sizeof(void *) * 2,(unsigned long)entry->end,
134 			    (entry->protection & VM_PROT_READ) ? 'r' : '-',
135 			    (entry->protection & VM_PROT_WRITE) ? 'w' : '-',
136 			    (entry->protection & VM_PROT_EXECUTE) ? 'x' : '-',
137 			    (entry->etype & UVM_ET_COPYONWRITE) ? 'p' : 's',
138 			    (int)sizeof(void *) * 2,
139 			    (unsigned long)entry->offset,
140 			    major(dev), minor(dev), fileid, path);
141 			free(path, M_TEMP);
142 		} else {
143 			snprintf(mebuffer, sizeof(mebuffer),
144 			    "0x%lx 0x%lx %c%c%c %c%c%c %s %s %d %d %d\n",
145 			    entry->start, entry->end,
146 			    (entry->protection & VM_PROT_READ) ? 'r' : '-',
147 			    (entry->protection & VM_PROT_WRITE) ? 'w' : '-',
148 			    (entry->protection & VM_PROT_EXECUTE) ? 'x' : '-',
149 			    (entry->max_protection & VM_PROT_READ) ? 'r' : '-',
150 			    (entry->max_protection & VM_PROT_WRITE) ? 'w' : '-',
151 			    (entry->max_protection & VM_PROT_EXECUTE) ?
152 				'x' : '-',
153 			    (entry->etype & UVM_ET_COPYONWRITE) ?
154 				"COW" : "NCOW",
155 			    (entry->etype & UVM_ET_NEEDSCOPY) ? "NC" : "NNC",
156 			    entry->inheritance, entry->wired_count,
157 			    entry->advice);
158 		}
159 
160 		len = strlen(mebuffer);
161 		if (len > uio->uio_resid) {
162 			error = EFBIG;
163 			break;
164 		}
165 		error = uiomove(mebuffer, len, uio);
166 		if (error)
167 			break;
168 	}
169 	if (map != &curproc->p_vmspace->vm_map)
170 		vm_map_unlock_read(map);
171 	return error;
172 }
173 
174 int
175 procfs_validmap(struct proc *p, struct mount *mp)
176 {
177 	return ((p->p_flag & P_SYSTEM) == 0);
178 }
179 
180 /*
181  * Try to find a pathname for a vnode. Since there is no mapping
182  * vnode -> parent directory, this needs the NAMECACHE_ENTER_REVERSE
183  * option to work (to make cache_revlookup succeed).
184  */
185 static int procfs_vnode_to_path(struct vnode *vp, char *path, int len,
186 				struct proc *curp, struct proc *p)
187 {
188 	int error, lenused, elen;
189 	char *bp, *bend;
190 	struct vnode *dvp;
191 
192 	bp = bend = &path[len];
193 	*(--bp) = '\0';
194 
195 	error = vget(vp, LK_EXCLUSIVE | LK_RETRY);
196 	if (error != 0)
197 		return error;
198 	error = cache_revlookup(vp, &dvp, &bp, path);
199 	vput(vp);
200 	if (error != 0)
201 		return (error == -1 ? ENOENT : error);
202 
203 	error = vget(dvp, 0);
204 	if (error != 0)
205 		return error;
206 	*(--bp) = '/';
207 	/* XXX GETCWD_CHECK_ACCESS == 0x0001 */
208 	error = getcwd_common(dvp, NULL, &bp, path, len / 2, 1, curp);
209 
210 	/*
211 	 * Strip off emulation path for emulated processes looking at
212 	 * the maps file of a process of the same emulation. (Won't
213 	 * work if /emul/xxx is a symlink..)
214 	 */
215 	if (curp->p_emul == p->p_emul && curp->p_emul->e_path != NULL) {
216 		elen = strlen(curp->p_emul->e_path);
217 		if (!strncmp(bp, curp->p_emul->e_path, elen))
218 			bp = &bp[elen];
219 	}
220 
221 	lenused = bend - bp;
222 
223 	memcpy(path, bp, lenused);
224 	path[lenused] = 0;
225 
226 	return 0;
227 }
228