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Ignore whitespace Rev 741 → Rev 746

/kernel/trunk/genarch/include/mm/page_ht.h
36,7 → 36,11
#define __PAGE_HT_H__
 
#include <mm/page.h>
#include <typedefs.h>
 
/** Number of slots in page hash table. */
#define HT_ENTRIES HT_ENTRIES_ARCH
 
/** Hash function.
*
* @param page Virtual address. Only vpn bits will be used.
56,7 → 60,7
*/
#define HT_COMPARE(page, asid, t) HT_COMPARE_ARCH(page, asid, t)
 
/** Identify empty hash table slots.
/** Identify empty page hash table slots.
*
* @param t Pointer ro hash table typed pte_t *.
*
64,6 → 68,12
*/
#define HT_SLOT_EMPTY(t) HT_SLOT_EMPTY_ARCH(t)
 
/** Invalidate/empty page hash table slot.
*
* @param t Address of the slot to be invalidated.
*/
#define HT_INVALIDATE_SLOT(t) HT_INVALIDATE_SLOT_ARCH(t)
 
/** Return next record in collision chain.
*
* @param t PTE.
89,6 → 99,12
*/
#define HT_SET_RECORD(t, page, asid, frame, flags) HT_SET_RECORD_ARCH(t, page, asid, frame, flags)
 
 
extern page_operations_t page_ht_operations;
extern spinlock_t page_ht_lock;
 
extern pte_t *page_ht;
 
extern void ht_invalidate_all(void);
 
#endif
/kernel/trunk/genarch/src/mm/page_ht.c
34,8 → 34,24
#include <arch/types.h>
#include <typedefs.h>
#include <arch/asm.h>
#include <synch/spinlock.h>
#include <arch.h>
#include <debug.h>
 
/**
* This lock protects the page hash table. Note that software must
* be still careful about ordering of writes to ensure consistent
* view of the page hash table for hardware helpers such as VHPT
* walker on ia64.
*/
SPINLOCK_INITIALIZE(page_ht_lock);
 
/**
* Page hash table pointer.
* The page hash table may be accessed only when page_ht_lock is held.
*/
pte_t *page_ht = NULL;
 
static void ht_mapping_insert(__address page, asid_t asid, __address frame, int flags, __address root);
static pte_t *ht_mapping_find(__address page, asid_t asid, __address root);
 
47,7 → 63,9
/** Map page to frame using page hash table.
*
* Map virtual address 'page' to physical address 'frame'
* using 'flags'.
* using 'flags'. In order not to disturb hardware searching,
* new mappings are appended to the end of the collision
* chain.
*
* @param page Virtual address of the page to be mapped.
* @param asid Address space to which page belongs.
57,17 → 75,45
*/
void ht_mapping_insert(__address page, asid_t asid, __address frame, int flags, __address root)
{
pte_t *t, *u = NULL;
pte_t *t, *u;
ipl_t ipl;
ipl = interrupts_disable();
spinlock_lock(&page_ht_lock);
t = HT_HASH(page, asid);
if (!HT_SLOT_EMPTY(t)) {
u = (pte_t *) malloc(sizeof(pte_t)); /* FIXME: use slab allocator for this */
if (!u)
panic("could not allocate memory for hash table\n");
*u = *t;
/*
* The slot is occupied.
* Walk through the collision chain and append the mapping to its end.
*/
do {
u = t;
if (HT_COMPARE(page, asid, t)) {
/*
* Nothing to do,
* the record is already there.
*/
spinlock_unlock(&page_ht_lock);
interrupts_restore(ipl);
return;
}
} while ((t = HT_GET_NEXT(t)));
t = (pte_t *) malloc(sizeof(pte_t)); /* FIXME: use slab allocator for this */
if (!t)
panic("could not allocate memory\n");
 
HT_SET_NEXT(u, t);
}
HT_SET_NEXT(t, u);
HT_SET_RECORD(t, page, asid, frame, flags);
HT_SET_NEXT(t, NULL);
spinlock_unlock(&page_ht_lock);
interrupts_restore(ipl);
}
 
/** Find mapping for virtual page in page hash table.
74,6 → 120,8
*
* Find mapping for virtual page.
*
* Interrupts must be disabled.
*
* @param page Virtual page.
* @param asid Address space to wich page belongs.
* @param root Ignored.
84,9 → 132,39
{
pte_t *t;
spinlock_lock(&page_ht_lock);
t = HT_HASH(page, asid);
while (!HT_COMPARE(page, asid, t) && HT_GET_NEXT(t))
t = HT_GET_NEXT(t);
if (!HT_SLOT_EMPTY(t)) {
while (!HT_COMPARE(page, asid, t) && HT_GET_NEXT(t))
t = HT_GET_NEXT(t);
t = HT_COMPARE(page, asid, t) ? t : NULL;
} else {
t = NULL;
}
spinlock_unlock(&page_ht_lock);
return t;
}
 
/** Invalidate page hash table.
*
* Interrupts must be disabled.
*/
void ht_invalidate_all(void)
{
pte_t *t, *u;
int i;
return HT_COMPARE(page, asid, t) ? t : NULL;
spinlock_lock(&page_ht_lock);
for (i = 0; i < HT_ENTRIES; i++) {
if (!HT_SLOT_EMPTY(&page_ht[i])) {
t = HT_GET_NEXT(&page_ht[i]);
while (t) {
u = t;
t = HT_GET_NEXT(t);
free(u); /* FIXME: use slab allocator for this */
}
HT_INVALIDATE_SLOT(&page_ht[i]);
}
}
spinlock_unlock(&page_ht_lock);
}