NetBSD/sys/kern/exec_subr.c

291 lines
7.4 KiB
C

/* $NetBSD: exec_subr.c,v 1.20 2000/06/27 17:41:12 mrg Exp $ */
/*
* Copyright (c) 1993, 1994, 1996 Christopher G. Demetriou
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Christopher G. Demetriou.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/filedesc.h>
#include <sys/exec.h>
#include <sys/mman.h>
#include <uvm/uvm.h>
/*
* XXX cgd 960926: this module should collect simple statistics
* (calls, extends, kills).
*/
#ifdef DEBUG
/*
* new_vmcmd():
* create a new vmcmd structure and fill in its fields based
* on function call arguments. make sure objects ref'd by
* the vmcmd are 'held'.
*
* If not debugging, this is a macro, so it's expanded inline.
*/
void
new_vmcmd(evsp, proc, len, addr, vp, offset, prot)
struct exec_vmcmd_set *evsp;
int (*proc) __P((struct proc * p, struct exec_vmcmd *));
u_long len;
u_long addr;
struct vnode *vp;
u_long offset;
u_int prot;
{
struct exec_vmcmd *vcp;
if (evsp->evs_used >= evsp->evs_cnt)
vmcmdset_extend(evsp);
vcp = &evsp->evs_cmds[evsp->evs_used++];
vcp->ev_proc = proc;
vcp->ev_len = len;
vcp->ev_addr = addr;
if ((vcp->ev_vp = vp) != NULL)
vref(vp);
vcp->ev_offset = offset;
vcp->ev_prot = prot;
}
#endif /* DEBUG */
void
vmcmdset_extend(evsp)
struct exec_vmcmd_set *evsp;
{
struct exec_vmcmd *nvcp;
u_int ocnt;
#ifdef DIAGNOSTIC
if (evsp->evs_used < evsp->evs_cnt)
panic("vmcmdset_extend: not necessary");
#endif
/* figure out number of entries in new set */
ocnt = evsp->evs_cnt;
evsp->evs_cnt += ocnt ? ocnt : EXEC_DEFAULT_VMCMD_SETSIZE;
/* allocate it */
MALLOC(nvcp, struct exec_vmcmd *,
(evsp->evs_cnt * sizeof(struct exec_vmcmd)), M_EXEC, M_WAITOK);
/* free the old struct, if there was one, and record the new one */
if (ocnt) {
memcpy(nvcp, evsp->evs_cmds, (ocnt * sizeof(struct exec_vmcmd)));
FREE(evsp->evs_cmds, M_EXEC);
}
evsp->evs_cmds = nvcp;
}
void
kill_vmcmds(evsp)
struct exec_vmcmd_set *evsp;
{
struct exec_vmcmd *vcp;
int i;
if (evsp->evs_cnt == 0)
return;
for (i = 0; i < evsp->evs_used; i++) {
vcp = &evsp->evs_cmds[i];
if (vcp->ev_vp != NULLVP)
vrele(vcp->ev_vp);
}
evsp->evs_used = evsp->evs_cnt = 0;
FREE(evsp->evs_cmds, M_EXEC);
}
/*
* vmcmd_map_pagedvn():
* handle vmcmd which specifies that a vnode should be mmap'd.
* appropriate for handling demand-paged text and data segments.
*/
int
vmcmd_map_pagedvn(p, cmd)
struct proc *p;
struct exec_vmcmd *cmd;
{
/*
* note that if you're going to map part of an process as being
* paged from a vnode, that vnode had damn well better be marked as
* VTEXT. that's handled in the routine which sets up the vmcmd to
* call this routine.
*/
struct uvm_object *uobj;
int retval;
/*
* map the vnode in using uvm_map.
*/
/* checks imported from uvm_mmap, needed? */
if (cmd->ev_len == 0)
return(0);
if (cmd->ev_offset & PAGE_MASK)
return(EINVAL);
if (cmd->ev_addr & PAGE_MASK)
return(EINVAL);
if (cmd->ev_len & PAGE_MASK)
return(EINVAL);
/*
* first, attach to the object
*/
uobj = uvn_attach((void *) cmd->ev_vp, VM_PROT_READ|VM_PROT_EXECUTE);
if (uobj == NULL)
return(ENOMEM);
/*
* do the map
*/
retval = uvm_map(&p->p_vmspace->vm_map, &cmd->ev_addr, cmd->ev_len,
uobj, cmd->ev_offset,
UVM_MAPFLAG(cmd->ev_prot, VM_PROT_ALL, UVM_INH_COPY,
UVM_ADV_NORMAL, UVM_FLAG_COPYONW|UVM_FLAG_FIXED));
/*
* check for error
*/
if (retval == KERN_SUCCESS)
return(0);
/*
* error: detach from object
*/
uobj->pgops->pgo_detach(uobj);
return (EINVAL);
}
/*
* vmcmd_map_readvn():
* handle vmcmd which specifies that a vnode should be read from.
* appropriate for non-demand-paged text/data segments, i.e. impure
* objects (a la OMAGIC and NMAGIC).
*/
int
vmcmd_map_readvn(p, cmd)
struct proc *p;
struct exec_vmcmd *cmd;
{
int error;
long diff;
if (cmd->ev_len == 0)
return(KERN_SUCCESS); /* XXXCDC: should it happen? */
diff = cmd->ev_addr - trunc_page(cmd->ev_addr);
cmd->ev_addr -= diff; /* required by uvm_map */
cmd->ev_offset -= diff;
cmd->ev_len += diff;
error = uvm_map(&p->p_vmspace->vm_map, &cmd->ev_addr,
round_page(cmd->ev_len), NULL, UVM_UNKNOWN_OFFSET,
UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
UVM_ADV_NORMAL,
UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW));
if (error)
return error;
return vmcmd_readvn(p, cmd);
}
int
vmcmd_readvn(p, cmd)
struct proc *p;
struct exec_vmcmd *cmd;
{
int error;
error = vn_rdwr(UIO_READ, cmd->ev_vp, (caddr_t)cmd->ev_addr,
cmd->ev_len, cmd->ev_offset, UIO_USERSPACE, IO_UNIT,
p->p_ucred, NULL, p);
if (error)
return error;
if (cmd->ev_prot != (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)) {
/*
* we had to map in the area at PROT_ALL so that vn_rdwr()
* could write to it. however, the caller seems to want
* it mapped read-only, so now we are going to have to call
* uvm_map_protect() to fix up the protection. ICK.
*/
return(uvm_map_protect(&p->p_vmspace->vm_map,
trunc_page(cmd->ev_addr),
round_page(cmd->ev_addr + cmd->ev_len),
cmd->ev_prot, FALSE));
} else {
return (KERN_SUCCESS);
}
}
/*
* vmcmd_map_zero():
* handle vmcmd which specifies a zero-filled address space region. The
* address range must be first allocated, then protected appropriately.
*/
int
vmcmd_map_zero(p, cmd)
struct proc *p;
struct exec_vmcmd *cmd;
{
int error;
long diff;
if (cmd->ev_len == 0)
return(KERN_SUCCESS); /* XXXCDC: should it happen? */
diff = cmd->ev_addr - trunc_page(cmd->ev_addr);
cmd->ev_addr -= diff; /* required by uvm_map */
cmd->ev_len += diff;
error = uvm_map(&p->p_vmspace->vm_map, &cmd->ev_addr,
round_page(cmd->ev_len), NULL, UVM_UNKNOWN_OFFSET,
UVM_MAPFLAG(cmd->ev_prot, UVM_PROT_ALL, UVM_INH_COPY,
UVM_ADV_NORMAL,
UVM_FLAG_FIXED|UVM_FLAG_COPYONW));
if (error)
return error;
return (KERN_SUCCESS);
}