1 /* $NetBSD: exec_subr.c,v 1.21 2000/07/13 09:34:23 mjacob Exp $ */ 2 3 /* 4 * Copyright (c) 1993, 1994, 1996 Christopher G. Demetriou 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Christopher G. Demetriou. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/proc.h> 36 #include <sys/malloc.h> 37 #include <sys/vnode.h> 38 #include <sys/filedesc.h> 39 #include <sys/exec.h> 40 #include <sys/mman.h> 41 42 #include <uvm/uvm.h> 43 44 /* 45 * XXX cgd 960926: this module should collect simple statistics 46 * (calls, extends, kills). 47 */ 48 49 #ifdef DEBUG 50 /* 51 * new_vmcmd(): 52 * create a new vmcmd structure and fill in its fields based 53 * on function call arguments. make sure objects ref'd by 54 * the vmcmd are 'held'. 55 * 56 * If not debugging, this is a macro, so it's expanded inline. 57 */ 58 59 void 60 new_vmcmd(evsp, proc, len, addr, vp, offset, prot, flags) 61 struct exec_vmcmd_set *evsp; 62 int (*proc) __P((struct proc * p, struct exec_vmcmd *)); 63 u_long len; 64 u_long addr; 65 struct vnode *vp; 66 u_long offset; 67 u_int prot; 68 int flags; 69 { 70 struct exec_vmcmd *vcp; 71 72 if (evsp->evs_used >= evsp->evs_cnt) 73 vmcmdset_extend(evsp); 74 vcp = &evsp->evs_cmds[evsp->evs_used++]; 75 vcp->ev_proc = proc; 76 vcp->ev_len = len; 77 vcp->ev_addr = addr; 78 if ((vcp->ev_vp = vp) != NULL) 79 vref(vp); 80 vcp->ev_offset = offset; 81 vcp->ev_prot = prot; 82 vcp->ev_flags = flags; 83 } 84 #endif /* DEBUG */ 85 86 void 87 vmcmdset_extend(evsp) 88 struct exec_vmcmd_set *evsp; 89 { 90 struct exec_vmcmd *nvcp; 91 u_int ocnt; 92 93 #ifdef DIAGNOSTIC 94 if (evsp->evs_used < evsp->evs_cnt) 95 panic("vmcmdset_extend: not necessary"); 96 #endif 97 98 /* figure out number of entries in new set */ 99 ocnt = evsp->evs_cnt; 100 evsp->evs_cnt += ocnt ? ocnt : EXEC_DEFAULT_VMCMD_SETSIZE; 101 102 /* allocate it */ 103 MALLOC(nvcp, struct exec_vmcmd *, 104 (evsp->evs_cnt * sizeof(struct exec_vmcmd)), M_EXEC, M_WAITOK); 105 106 /* free the old struct, if there was one, and record the new one */ 107 if (ocnt) { 108 memcpy(nvcp, evsp->evs_cmds, (ocnt * sizeof(struct exec_vmcmd))); 109 FREE(evsp->evs_cmds, M_EXEC); 110 } 111 evsp->evs_cmds = nvcp; 112 } 113 114 void 115 kill_vmcmds(evsp) 116 struct exec_vmcmd_set *evsp; 117 { 118 struct exec_vmcmd *vcp; 119 int i; 120 121 if (evsp->evs_cnt == 0) 122 return; 123 124 for (i = 0; i < evsp->evs_used; i++) { 125 vcp = &evsp->evs_cmds[i]; 126 if (vcp->ev_vp != NULLVP) 127 vrele(vcp->ev_vp); 128 } 129 evsp->evs_used = evsp->evs_cnt = 0; 130 FREE(evsp->evs_cmds, M_EXEC); 131 } 132 133 /* 134 * vmcmd_map_pagedvn(): 135 * handle vmcmd which specifies that a vnode should be mmap'd. 136 * appropriate for handling demand-paged text and data segments. 137 */ 138 139 int 140 vmcmd_map_pagedvn(p, cmd) 141 struct proc *p; 142 struct exec_vmcmd *cmd; 143 { 144 /* 145 * note that if you're going to map part of an process as being 146 * paged from a vnode, that vnode had damn well better be marked as 147 * VTEXT. that's handled in the routine which sets up the vmcmd to 148 * call this routine. 149 */ 150 struct uvm_object *uobj; 151 int retval; 152 153 /* 154 * map the vnode in using uvm_map. 155 */ 156 157 /* checks imported from uvm_mmap, needed? */ 158 if (cmd->ev_len == 0) 159 return(0); 160 if (cmd->ev_offset & PAGE_MASK) 161 return(EINVAL); 162 if (cmd->ev_addr & PAGE_MASK) 163 return(EINVAL); 164 if (cmd->ev_len & PAGE_MASK) 165 return(EINVAL); 166 167 /* 168 * first, attach to the object 169 */ 170 171 uobj = uvn_attach((void *) cmd->ev_vp, VM_PROT_READ|VM_PROT_EXECUTE); 172 if (uobj == NULL) 173 return(ENOMEM); 174 175 /* 176 * do the map 177 */ 178 179 retval = uvm_map(&p->p_vmspace->vm_map, &cmd->ev_addr, cmd->ev_len, 180 uobj, cmd->ev_offset, 181 UVM_MAPFLAG(cmd->ev_prot, VM_PROT_ALL, UVM_INH_COPY, 182 UVM_ADV_NORMAL, UVM_FLAG_COPYONW|UVM_FLAG_FIXED)); 183 184 /* 185 * check for error 186 */ 187 188 if (retval == KERN_SUCCESS) 189 return(0); 190 191 /* 192 * error: detach from object 193 */ 194 195 uobj->pgops->pgo_detach(uobj); 196 return (EINVAL); 197 } 198 199 /* 200 * vmcmd_map_readvn(): 201 * handle vmcmd which specifies that a vnode should be read from. 202 * appropriate for non-demand-paged text/data segments, i.e. impure 203 * objects (a la OMAGIC and NMAGIC). 204 */ 205 int 206 vmcmd_map_readvn(p, cmd) 207 struct proc *p; 208 struct exec_vmcmd *cmd; 209 { 210 int error; 211 long diff; 212 213 if (cmd->ev_len == 0) 214 return(KERN_SUCCESS); /* XXXCDC: should it happen? */ 215 216 diff = cmd->ev_addr - trunc_page(cmd->ev_addr); 217 cmd->ev_addr -= diff; /* required by uvm_map */ 218 cmd->ev_offset -= diff; 219 cmd->ev_len += diff; 220 221 error = uvm_map(&p->p_vmspace->vm_map, &cmd->ev_addr, 222 round_page(cmd->ev_len), NULL, UVM_UNKNOWN_OFFSET, 223 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY, 224 UVM_ADV_NORMAL, 225 UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)); 226 227 if (error) 228 return error; 229 230 return vmcmd_readvn(p, cmd); 231 } 232 233 int 234 vmcmd_readvn(p, cmd) 235 struct proc *p; 236 struct exec_vmcmd *cmd; 237 { 238 int error; 239 240 error = vn_rdwr(UIO_READ, cmd->ev_vp, (caddr_t)cmd->ev_addr, 241 cmd->ev_len, cmd->ev_offset, UIO_USERSPACE, IO_UNIT, 242 p->p_ucred, NULL, p); 243 if (error) 244 return error; 245 246 if (cmd->ev_prot != (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)) { 247 /* 248 * we had to map in the area at PROT_ALL so that vn_rdwr() 249 * could write to it. however, the caller seems to want 250 * it mapped read-only, so now we are going to have to call 251 * uvm_map_protect() to fix up the protection. ICK. 252 */ 253 return(uvm_map_protect(&p->p_vmspace->vm_map, 254 trunc_page(cmd->ev_addr), 255 round_page(cmd->ev_addr + cmd->ev_len), 256 cmd->ev_prot, FALSE)); 257 } else { 258 return (KERN_SUCCESS); 259 } 260 } 261 262 /* 263 * vmcmd_map_zero(): 264 * handle vmcmd which specifies a zero-filled address space region. The 265 * address range must be first allocated, then protected appropriately. 266 */ 267 268 int 269 vmcmd_map_zero(p, cmd) 270 struct proc *p; 271 struct exec_vmcmd *cmd; 272 { 273 int error; 274 long diff; 275 276 if (cmd->ev_len == 0) 277 return(KERN_SUCCESS); /* XXXCDC: should it happen? */ 278 279 diff = cmd->ev_addr - trunc_page(cmd->ev_addr); 280 cmd->ev_addr -= diff; /* required by uvm_map */ 281 cmd->ev_len += diff; 282 283 error = uvm_map(&p->p_vmspace->vm_map, &cmd->ev_addr, 284 round_page(cmd->ev_len), NULL, UVM_UNKNOWN_OFFSET, 285 UVM_MAPFLAG(cmd->ev_prot, UVM_PROT_ALL, UVM_INH_COPY, 286 UVM_ADV_NORMAL, 287 UVM_FLAG_FIXED|UVM_FLAG_COPYONW)); 288 289 if (error) 290 return error; 291 return (KERN_SUCCESS); 292 } 293