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