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/*
* Copyright (c) 1996, 1998, 1999 University of Utah and the Flux Group.
* All rights reserved.
*
* This file is part of the Flux OSKit. The OSKit is free software, also known
* as "open source;" you can redistribute it and/or modify it under the terms
* of the GNU General Public License (GPL), version 2, as published by the Free
* Software Foundation (FSF). To explore alternate licensing terms, contact
* the University of Utah at csl-dist@cs.utah.edu or +1-801-585-3271.
*
* The OSKit is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GPL for more details. You should have
* received a copy of the GPL along with the OSKit; see the file COPYING. If
* not, write to the FSF, 59 Temple Place #330, Boston, MA 02111-1307, USA.
*/
#include "svm_internal.h"
/*
* Allocate a region. Allow the caller to request a specific location,
* but fail if that location is not available.
*
* Address and len must be page aligned.
*/
int
svm_alloc(oskit_addr_t *addrp, oskit_size_t len, int prot, int flags)
{
oskit_addr_t base = *addrp;
oskit_error_t error = 0;
oskit_addr_t vaddr;
oskit_size_t tmp = len;
unsigned int mbits;
/*
* Check for page alignment of both address and length.
*/
if ((base && !page_aligned(base)) || !page_aligned(len))
return OSKIT_E_INVALIDARG;
/*
* Allow READ or READ/WRITE only.
*/
if ((prot & SVM_PROT_READ) == 0)
return OSKIT_E_INVALIDARG;
SVM_LOCK();
/*
* Now try to allocate the region from the AMM, checking first
* if the request is "fixed."
*/
if (base && (flags & SVM_ALLOC_FIXED)) {
struct amm_entry *entry;
entry = amm_find_gen(&svm_amm, &base,
len, AMM_FREE, -1, 0, 0, AMM_EXACT_ADDR);
if (entry == 0) {
SVM_UNLOCK();
return OSKIT_E_OUTOFMEMORY;
}
}
if ((error = amm_allocate(&svm_amm, &base, len, prot)) != 0) {
SVM_UNLOCK();
return error;
}
#ifdef DEBUG_SVM
printf("svm_alloc: 0x%x\n", base);
#endif
/*
* Don't bother to allocate memory. That will happen when the
* page is first referenced. Just set up the mappings and mark
* them as zfill so they fault.
*/
mbits = PTE_MBITS_ZFILL |
((prot & SVM_PROT_WIRED) ? PTE_MBITS_WIRED : 0) |
((prot & SVM_PROT_WRITE) ? PTE_MBITS_RW : PTE_MBITS_R);
if (svm_map_range(base, 0, len, mbits))
panic("svm_alloc: Can't map physical memory");
SVM_UNLOCK();
/*
* Well, if the region was created as wired, go through faulting
* in the pages.
*/
if (prot & SVM_PROT_WIRED) {
vaddr = (oskit_addr_t) base;
tmp = len;
while (tmp > 0) {
svm_fault(vaddr, 0);
tmp -= PAGE_SIZE;
vaddr += PAGE_SIZE;
}
}
*addrp = base;
return 0;
}
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