procfs_map.c revision 168968
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 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)procfs_status.c 8.3 (Berkeley) 2/17/94 34 * 35 * $FreeBSD: head/sys/fs/procfs/procfs_map.c 168968 2007-04-23 06:12:24Z alc $ 36 */ 37 38#include "opt_compat.h" 39 40#include <sys/param.h> 41#include <sys/systm.h> 42#include <sys/lock.h> 43#include <sys/filedesc.h> 44#include <sys/malloc.h> 45#include <sys/mount.h> 46#include <sys/mutex.h> 47#include <sys/proc.h> 48#include <sys/uio.h> 49#include <sys/vnode.h> 50 51#include <fs/pseudofs/pseudofs.h> 52#include <fs/procfs/procfs.h> 53 54#include <vm/vm.h> 55#include <vm/pmap.h> 56#include <vm/vm_map.h> 57#include <vm/vm_page.h> 58#include <vm/vm_object.h> 59 60#ifdef COMPAT_IA32 61#include <sys/procfs.h> 62#include <machine/fpu.h> 63#include <compat/ia32/ia32_reg.h> 64 65extern struct sysentvec ia32_freebsd_sysvec; 66#endif 67 68 69#define MEBUFFERSIZE 256 70 71/* 72 * The map entries can *almost* be read with programs like cat. However, 73 * large maps need special programs to read. It is not easy to implement 74 * a program that can sense the required size of the buffer, and then 75 * subsequently do a read with the appropriate size. This operation cannot 76 * be atomic. The best that we can do is to allow the program to do a read 77 * with an arbitrarily large buffer, and return as much as we can. We can 78 * return an error code if the buffer is too small (EFBIG), then the program 79 * can try a bigger buffer. 80 */ 81int 82procfs_doprocmap(PFS_FILL_ARGS) 83{ 84 int len; 85 int error, vfslocked; 86 vm_map_t map = &p->p_vmspace->vm_map; 87 vm_map_entry_t entry, tmp_entry; 88 struct vnode *vp; 89 char mebuffer[MEBUFFERSIZE]; 90 char *fullpath, *freepath; 91 unsigned int last_timestamp; 92#ifdef COMPAT_IA32 93 int wrap32 = 0; 94#endif 95 96 PROC_LOCK(p); 97 error = p_candebug(td, p); 98 PROC_UNLOCK(p); 99 if (error) 100 return (error); 101 102 if (uio->uio_rw != UIO_READ) 103 return (EOPNOTSUPP); 104 105 if (uio->uio_offset != 0) 106 return (0); 107 108#ifdef COMPAT_IA32 109 if (curthread->td_proc->p_sysent == &ia32_freebsd_sysvec) { 110 if (p->p_sysent != &ia32_freebsd_sysvec) 111 return (EOPNOTSUPP); 112 wrap32 = 1; 113 } 114#endif 115 116 vm_map_lock_read(map); 117 for (entry = map->header.next; 118 ((uio->uio_resid > 0) && (entry != &map->header)); 119 entry = entry->next) { 120 vm_object_t obj, tobj, lobj; 121 int ref_count, shadow_count, flags; 122 vm_offset_t addr; 123 int resident, privateresident; 124 char *type; 125 126 if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) 127 continue; 128 129 privateresident = 0; 130 obj = entry->object.vm_object; 131 if (obj != NULL) { 132 VM_OBJECT_LOCK(obj); 133 if (obj->shadow_count == 1) 134 privateresident = obj->resident_page_count; 135 } 136 137 resident = 0; 138 addr = entry->start; 139 while (addr < entry->end) { 140 if (pmap_extract(map->pmap, addr)) 141 resident++; 142 addr += PAGE_SIZE; 143 } 144 145 for (lobj = tobj = obj; tobj; tobj = tobj->backing_object) { 146 if (tobj != obj) 147 VM_OBJECT_LOCK(tobj); 148 if (lobj != obj) 149 VM_OBJECT_UNLOCK(lobj); 150 lobj = tobj; 151 } 152 153 freepath = NULL; 154 fullpath = "-"; 155 if (lobj) { 156 switch(lobj->type) { 157 default: 158 case OBJT_DEFAULT: 159 type = "default"; 160 vp = NULL; 161 break; 162 case OBJT_VNODE: 163 type = "vnode"; 164 vp = lobj->handle; 165 vref(vp); 166 break; 167 case OBJT_SWAP: 168 type = "swap"; 169 vp = NULL; 170 break; 171 case OBJT_DEVICE: 172 type = "device"; 173 vp = NULL; 174 break; 175 } 176 if (lobj != obj) 177 VM_OBJECT_UNLOCK(lobj); 178 179 flags = obj->flags; 180 ref_count = obj->ref_count; 181 shadow_count = obj->shadow_count; 182 VM_OBJECT_UNLOCK(obj); 183 if (vp != NULL) { 184 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 185 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 186 vn_fullpath(td, vp, &fullpath, &freepath); 187 vput(vp); 188 VFS_UNLOCK_GIANT(vfslocked); 189 } 190 } else { 191 type = "none"; 192 flags = 0; 193 ref_count = 0; 194 shadow_count = 0; 195 } 196 197 /* 198 * format: 199 * start, end, resident, private resident, cow, access, type. 200 */ 201 snprintf(mebuffer, sizeof mebuffer, 202 "0x%lx 0x%lx %d %d %p %s%s%s %d %d 0x%x %s %s %s %s\n", 203 (u_long)entry->start, (u_long)entry->end, 204 resident, privateresident, 205#ifdef COMPAT_IA32 206 wrap32 ? NULL : obj, /* Hide 64 bit value */ 207#else 208 obj, 209#endif 210 (entry->protection & VM_PROT_READ)?"r":"-", 211 (entry->protection & VM_PROT_WRITE)?"w":"-", 212 (entry->protection & VM_PROT_EXECUTE)?"x":"-", 213 ref_count, shadow_count, flags, 214 (entry->eflags & MAP_ENTRY_COW)?"COW":"NCOW", 215 (entry->eflags & MAP_ENTRY_NEEDS_COPY)?"NC":"NNC", 216 type, fullpath); 217 218 if (freepath != NULL) 219 free(freepath, M_TEMP); 220 221 len = strlen(mebuffer); 222 if (len > uio->uio_resid) { 223 error = EFBIG; 224 break; 225 } 226 last_timestamp = map->timestamp; 227 vm_map_unlock_read(map); 228 error = uiomove(mebuffer, len, uio); 229 vm_map_lock_read(map); 230 if (error) 231 break; 232 if (last_timestamp + 1 != map->timestamp) { 233 /* 234 * Look again for the entry because the map was 235 * modified while it was unlocked. Specifically, 236 * the entry may have been clipped, merged, or deleted. 237 */ 238 vm_map_lookup_entry(map, addr - 1, &tmp_entry); 239 entry = tmp_entry; 240 } 241 } 242 vm_map_unlock_read(map); 243 return (error); 244} 245