312 lines
8.0 KiB
C
312 lines
8.0 KiB
C
/*
|
|
* Copyright (c) 1992 William F. Jolitz, TeleMuse
|
|
* 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 software is a component of "386BSD" developed by
|
|
William F. Jolitz, TeleMuse.
|
|
* 4. Neither the name of the developer nor the name "386BSD"
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS A COMPONENT OF 386BSD DEVELOPED BY WILLIAM F. JOLITZ
|
|
* AND IS INTENDED FOR RESEARCH AND EDUCATIONAL PURPOSES ONLY. THIS
|
|
* SOFTWARE SHOULD NOT BE CONSIDERED TO BE A COMMERCIAL PRODUCT.
|
|
* THE DEVELOPER URGES THAT USERS WHO REQUIRE A COMMERCIAL PRODUCT
|
|
* NOT MAKE USE THIS WORK.
|
|
*
|
|
* FOR USERS WHO WISH TO UNDERSTAND THE 386BSD SYSTEM DEVELOPED
|
|
* BY WILLIAM F. JOLITZ, WE RECOMMEND THE USER STUDY WRITTEN
|
|
* REFERENCES SUCH AS THE "PORTING UNIX TO THE 386" SERIES
|
|
* (BEGINNING JANUARY 1991 "DR. DOBBS JOURNAL", USA AND BEGINNING
|
|
* JUNE 1991 "UNIX MAGAZIN", GERMANY) BY WILLIAM F. JOLITZ AND
|
|
* LYNNE GREER JOLITZ, AS WELL AS OTHER BOOKS ON UNIX AND THE
|
|
* ON-LINE 386BSD USER MANUAL BEFORE USE. A BOOK DISCUSSING THE INTERNALS
|
|
* OF 386BSD ENTITLED "386BSD FROM THE INSIDE OUT" WILL BE AVAILABLE LATE 1992.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE DEVELOPER ``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 DEVELOPER 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.
|
|
*
|
|
*/
|
|
/*
|
|
* Changes Copyright (C) 1995, David Greenman & John Dyson; This software may
|
|
* be used, modified, copied, distributed, and sold, in both source and
|
|
* binary form provided that the above copyright and these terms are
|
|
* retained. Under no circumstances is the author responsible for the proper
|
|
* functioning of this software, nor does the author assume any responsibility
|
|
* for damages incurred with its use.
|
|
*
|
|
* $Id$
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/rlist.h>
|
|
#include <sys/proc.h>
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_param.h>
|
|
#include <vm/vm_kern.h>
|
|
#include <vm/vm_extern.h>
|
|
|
|
/*
|
|
* Resource lists.
|
|
*/
|
|
|
|
#define RLIST_MIN 128
|
|
static int rlist_count=0;
|
|
static struct rlist *rlfree;
|
|
|
|
static struct rlist *rlist_malloc __P((void));
|
|
|
|
static struct rlist *
|
|
rlist_malloc()
|
|
{
|
|
struct rlist *rl;
|
|
int i;
|
|
while( rlist_count < RLIST_MIN) {
|
|
int s = splhigh();
|
|
rl = (struct rlist *)kmem_alloc(kernel_map, PAGE_SIZE);
|
|
splx(s);
|
|
if( !rl)
|
|
break;
|
|
|
|
for(i=0;i<(PAGE_SIZE/(sizeof *rl));i++) {
|
|
rl->rl_next = rlfree;
|
|
rlfree = rl;
|
|
rlist_count++;
|
|
rl++;
|
|
}
|
|
}
|
|
|
|
if( (rl = rlfree) == 0 )
|
|
panic("Cannot get an rlist entry");
|
|
|
|
--rlist_count;
|
|
rlfree = rl->rl_next;
|
|
return rl;
|
|
}
|
|
|
|
inline static void
|
|
rlist_mfree( struct rlist *rl)
|
|
{
|
|
rl->rl_next = rlfree;
|
|
rlfree = rl;
|
|
++rlist_count;
|
|
}
|
|
|
|
void
|
|
rlist_free(rlh, start, end)
|
|
struct rlisthdr *rlh;
|
|
u_int start, end;
|
|
{
|
|
struct rlist **rlp = &rlh->rlh_list;
|
|
struct rlist *prev_rlp = NULL, *cur_rlp = *rlp, *next_rlp = NULL;
|
|
int s;
|
|
|
|
s = splhigh();
|
|
while (rlh->rlh_lock & RLH_LOCKED) {
|
|
rlh->rlh_lock |= RLH_DESIRED;
|
|
tsleep(rlh, PSWP, "rlistf", 0);
|
|
}
|
|
rlh->rlh_lock |= RLH_LOCKED;
|
|
splx(s);
|
|
|
|
/*
|
|
* Traverse the list looking for an entry after the one we want
|
|
* to insert.
|
|
*/
|
|
while (cur_rlp != NULL) {
|
|
if (start < cur_rlp->rl_start)
|
|
break;
|
|
#ifdef DIAGNOSTIC
|
|
if (prev_rlp) {
|
|
if (prev_rlp->rl_end + 1 == cur_rlp->rl_start)
|
|
panic("rlist_free: missed coalesce opportunity");
|
|
if (prev_rlp->rl_end == cur_rlp->rl_start)
|
|
panic("rlist_free: entries overlap");
|
|
if (prev_rlp->rl_end > cur_rlp->rl_start)
|
|
panic("entries out of order");
|
|
}
|
|
#endif
|
|
prev_rlp = cur_rlp;
|
|
cur_rlp = cur_rlp->rl_next;
|
|
}
|
|
|
|
if (cur_rlp != NULL) {
|
|
|
|
if (end >= cur_rlp->rl_start)
|
|
panic("rlist_free: free end overlaps already freed area");
|
|
|
|
if (prev_rlp) {
|
|
if (start <= prev_rlp->rl_end)
|
|
panic("rlist_free: free start overlaps already freed area");
|
|
/*
|
|
* Attempt to append
|
|
*/
|
|
if (prev_rlp->rl_end + 1 == start) {
|
|
prev_rlp->rl_end = end;
|
|
/*
|
|
* Attempt to prepend and coalesce
|
|
*/
|
|
if (end + 1 == cur_rlp->rl_start) {
|
|
prev_rlp->rl_end = cur_rlp->rl_end;
|
|
prev_rlp->rl_next = cur_rlp->rl_next;
|
|
rlist_mfree(cur_rlp);
|
|
}
|
|
goto done;
|
|
}
|
|
}
|
|
/*
|
|
* Attempt to prepend
|
|
*/
|
|
if (end + 1 == cur_rlp->rl_start) {
|
|
cur_rlp->rl_start = start;
|
|
goto done;
|
|
}
|
|
}
|
|
/*
|
|
* Reached the end of the list without finding a larger entry.
|
|
* Append to last entry if there is one and it's adjacent.
|
|
*/
|
|
if (prev_rlp) {
|
|
if (start <= prev_rlp->rl_end)
|
|
panic("rlist_free: free start overlaps already freed area at list tail");
|
|
/*
|
|
* Attempt to append
|
|
*/
|
|
if (prev_rlp->rl_end + 1 == start) {
|
|
prev_rlp->rl_end = end;
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Could neither append nor prepend; allocate a new entry.
|
|
*/
|
|
next_rlp = cur_rlp;
|
|
cur_rlp = rlist_malloc();
|
|
cur_rlp->rl_start = start;
|
|
cur_rlp->rl_end = end;
|
|
cur_rlp->rl_next = next_rlp;
|
|
if (prev_rlp) {
|
|
prev_rlp->rl_next = cur_rlp;
|
|
} else {
|
|
/*
|
|
* No previous - this entry is the new list head.
|
|
*/
|
|
*rlp = cur_rlp;
|
|
}
|
|
|
|
done:
|
|
rlh->rlh_lock &= ~RLH_LOCKED;
|
|
if (rlh->rlh_lock & RLH_DESIRED) {
|
|
wakeup(rlh);
|
|
rlh->rlh_lock &= ~RLH_DESIRED;
|
|
}
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Obtain a region of desired size from a resource list.
|
|
* If nothing available of that size, return 0. Otherwise,
|
|
* return a value of 1 and set resource start location with
|
|
* "*loc". (Note: loc can be zero if we don't wish the value)
|
|
*/
|
|
int
|
|
rlist_alloc (rlh, size, loc)
|
|
struct rlisthdr *rlh;
|
|
unsigned size, *loc;
|
|
{
|
|
struct rlist **rlp = &rlh->rlh_list;
|
|
register struct rlist *lp;
|
|
int s;
|
|
register struct rlist *olp = 0;
|
|
|
|
s = splhigh();
|
|
while (rlh->rlh_lock & RLH_LOCKED) {
|
|
rlh->rlh_lock |= RLH_DESIRED;
|
|
tsleep(rlh, PSWP, "rlistf", 0);
|
|
}
|
|
rlh->rlh_lock |= RLH_LOCKED;
|
|
splx(s);
|
|
|
|
/* walk list, allocating first thing that's big enough (first fit) */
|
|
for (; *rlp; rlp = &((*rlp)->rl_next))
|
|
if(size <= (*rlp)->rl_end - (*rlp)->rl_start + 1) {
|
|
|
|
/* hand it to the caller */
|
|
if (loc) *loc = (*rlp)->rl_start;
|
|
(*rlp)->rl_start += size;
|
|
|
|
/* did we eat this element entirely? */
|
|
if ((*rlp)->rl_start > (*rlp)->rl_end) {
|
|
lp = (*rlp)->rl_next;
|
|
rlist_mfree(*rlp);
|
|
/*
|
|
* if the deleted element was in fromt
|
|
* of the list, adjust *rlp, else don't.
|
|
*/
|
|
if (olp) {
|
|
olp->rl_next = lp;
|
|
} else {
|
|
*rlp = lp;
|
|
}
|
|
}
|
|
|
|
rlh->rlh_lock &= ~RLH_LOCKED;
|
|
if (rlh->rlh_lock & RLH_DESIRED) {
|
|
wakeup(rlh);
|
|
rlh->rlh_lock &= ~RLH_DESIRED;
|
|
}
|
|
return (1);
|
|
} else {
|
|
olp = *rlp;
|
|
}
|
|
|
|
rlh->rlh_lock &= ~RLH_LOCKED;
|
|
if (rlh->rlh_lock & RLH_DESIRED) {
|
|
wakeup(rlh);
|
|
rlh->rlh_lock &= ~RLH_DESIRED;
|
|
}
|
|
/* nothing in list that's big enough */
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Finished with this resource list, reclaim all space and
|
|
* mark it as being empty.
|
|
*/
|
|
void
|
|
rlist_destroy (rlh)
|
|
struct rlisthdr *rlh;
|
|
{
|
|
struct rlist **rlp = &rlh->rlh_list;
|
|
struct rlist *lp, *nlp;
|
|
|
|
lp = *rlp;
|
|
*rlp = 0;
|
|
for (; lp; lp = nlp) {
|
|
nlp = lp->rl_next;
|
|
rlist_mfree(lp);
|
|
}
|
|
}
|