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. 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: src/sys/miscfs/procfs/procfs_map.c,v 1.24.2.1 2001/08/04 13:12:24 rwatson Exp $ 36 * $DragonFly: src/sys/vfs/procfs/procfs_map.c,v 1.7 2007/02/19 01:14:24 corecode Exp $ 37 */ 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/proc.h> 42 #include <sys/vnode.h> 43 #include <vfs/procfs/procfs.h> 44 45 #include <vm/vm.h> 46 #include <sys/lock.h> 47 #include <vm/pmap.h> 48 #include <vm/vm_map.h> 49 #include <vm/vm_page.h> 50 #include <vm/vm_object.h> 51 52 #include <machine/limits.h> 53 54 #define MEBUFFERSIZE 256 55 56 /* 57 * The map entries can *almost* be read with programs like cat. However, 58 * large maps need special programs to read. It is not easy to implement 59 * a program that can sense the required size of the buffer, and then 60 * subsequently do a read with the appropriate size. This operation cannot 61 * be atomic. The best that we can do is to allow the program to do a read 62 * with an arbitrarily large buffer, and return as much as we can. We can 63 * return an error code if the buffer is too small (EFBIG), then the program 64 * can try a bigger buffer. 65 */ 66 int 67 procfs_domap(struct proc *curp, struct lwp *lp, struct pfsnode *pfs, 68 struct uio *uio) 69 { 70 struct proc *p = lp->lwp_proc; 71 int len; 72 struct vnode *vp; 73 char *fullpath, *freepath; 74 int error; 75 vm_map_t map = &p->p_vmspace->vm_map; 76 pmap_t pmap = vmspace_pmap(p->p_vmspace); 77 vm_map_entry_t entry; 78 char mebuffer[MEBUFFERSIZE]; 79 80 if (uio->uio_rw != UIO_READ) 81 return (EOPNOTSUPP); 82 83 if (uio->uio_offset != 0) 84 return (0); 85 86 error = 0; 87 vm_map_lock_read(map); 88 for (entry = map->header.next; 89 ((uio->uio_resid > 0) && (entry != &map->header)); 90 entry = entry->next) { 91 vm_object_t obj, tobj, lobj; 92 int ref_count, shadow_count, flags; 93 vm_offset_t addr; 94 vm_offset_t ostart; 95 int resident, privateresident; 96 char *type; 97 98 if (entry->maptype != VM_MAPTYPE_NORMAL && 99 entry->maptype != VM_MAPTYPE_VPAGETABLE) { 100 continue; 101 } 102 103 obj = entry->object.vm_object; 104 if (obj) 105 vm_object_hold(obj); 106 107 if (obj && (obj->shadow_count == 1)) 108 privateresident = obj->resident_page_count; 109 else 110 privateresident = 0; 111 112 /* 113 * Use map->hint as a poor man's ripout detector. 114 */ 115 map->hint = entry; 116 ostart = entry->start; 117 118 /* 119 * Count resident pages (XXX can be horrible on 64-bit) 120 */ 121 resident = 0; 122 addr = entry->start; 123 while (addr < entry->end) { 124 if (pmap_extract(pmap, addr)) 125 resident++; 126 addr += PAGE_SIZE; 127 } 128 if (obj) { 129 lobj = obj; 130 while ((tobj = lobj->backing_object) != NULL) { 131 KKASSERT(tobj != obj); 132 vm_object_hold(tobj); 133 if (tobj == lobj->backing_object) { 134 if (lobj != obj) { 135 vm_object_lock_swap(); 136 vm_object_drop(lobj); 137 } 138 lobj = tobj; 139 } else { 140 vm_object_drop(tobj); 141 } 142 } 143 } else { 144 lobj = NULL; 145 } 146 147 freepath = NULL; 148 fullpath = "-"; 149 if (lobj) { 150 switch(lobj->type) { 151 default: 152 case OBJT_DEFAULT: 153 type = "default"; 154 vp = NULL; 155 break; 156 case OBJT_VNODE: 157 type = "vnode"; 158 vp = lobj->handle; 159 vref(vp); 160 break; 161 case OBJT_SWAP: 162 type = "swap"; 163 vp = NULL; 164 break; 165 case OBJT_DEVICE: 166 type = "device"; 167 vp = NULL; 168 break; 169 case OBJT_MGTDEVICE: 170 type = "mgtdevice"; 171 vp = NULL; 172 break; 173 } 174 175 flags = obj->flags; 176 ref_count = obj->ref_count; 177 shadow_count = obj->shadow_count; 178 if (vp != NULL) { 179 vn_fullpath(p, vp, &fullpath, &freepath, 1); 180 vrele(vp); 181 } 182 if (lobj != obj) 183 vm_object_drop(lobj); 184 } else { 185 type = "none"; 186 flags = 0; 187 ref_count = 0; 188 shadow_count = 0; 189 } 190 191 /* 192 * format: 193 * start, end, res, priv res, cow, access, type, (fullpath). 194 */ 195 ksnprintf(mebuffer, sizeof(mebuffer), 196 #if LONG_BIT == 64 197 "0x%016lx 0x%016lx %d %d %p %s%s%s %d %d " 198 #else 199 "0x%08lx 0x%08lx %d %d %p %s%s%s %d %d " 200 #endif 201 "0x%04x %s %s %s %s\n", 202 (u_long)entry->start, (u_long)entry->end, 203 resident, privateresident, obj, 204 (entry->protection & VM_PROT_READ)?"r":"-", 205 (entry->protection & VM_PROT_WRITE)?"w":"-", 206 (entry->protection & VM_PROT_EXECUTE)?"x":"-", 207 ref_count, shadow_count, flags, 208 (entry->eflags & MAP_ENTRY_COW)?"COW":"NCOW", 209 (entry->eflags & MAP_ENTRY_NEEDS_COPY)?"NC":"NNC", 210 type, fullpath); 211 212 if (obj) 213 vm_object_drop(obj); 214 215 if (freepath != NULL) { 216 kfree(freepath, M_TEMP); 217 freepath = NULL; 218 } 219 220 len = strlen(mebuffer); 221 if (len > uio->uio_resid) { 222 error = EFBIG; 223 break; 224 } 225 226 /* 227 * We cannot safely hold the map locked while accessing 228 * userspace as a VM fault might recurse the locked map. 229 */ 230 vm_map_unlock_read(map); 231 error = uiomove(mebuffer, len, uio); 232 vm_map_lock_read(map); 233 if (error) 234 break; 235 236 /* 237 * We use map->hint as a poor man's ripout detector. If 238 * it does not match the entry we set it to prior to 239 * unlocking the map the entry MIGHT now be stale. In 240 * this case we do an expensive lookup to find our place 241 * in the iteration again. 242 */ 243 if (map->hint != entry) { 244 vm_map_entry_t reentry; 245 246 vm_map_lookup_entry(map, ostart, &reentry); 247 entry = reentry; 248 } 249 } 250 vm_map_unlock_read(map); 251 252 return error; 253 } 254 255 int 256 procfs_validmap(struct lwp *lp) 257 { 258 return ((lp->lwp_proc->p_flags & P_SYSTEM) == 0); 259 } 260