| 0,0 → 1,167 |
|---|
| /* |
| * Copyright (C) 2006 Jakub Jermar |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * - 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. |
| * - 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 <genarch/mm/page_ht.h> |
| #include <mm/page.h> |
| #include <mm/frame.h> |
| #include <mm/heap.h> |
| #include <mm/as.h> |
| #include <arch/mm/asid.h> |
| #include <arch/types.h> |
| #include <typedefs.h> |
| #include <arch/asm.h> |
| #include <synch/spinlock.h> |
| #include <arch.h> |
| #include <debug.h> |
| #include <memstr.h> |
| |
| /** |
| * This lock protects the page hash table. |
| */ |
| 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(as_t *as, __address page, __address frame, int flags); |
| static pte_t *ht_mapping_find(as_t *as, __address page); |
| |
| page_operations_t page_ht_operations = { |
| .mapping_insert = ht_mapping_insert, |
| .mapping_find = ht_mapping_find, |
| }; |
| |
| /** Map page to frame using page hash table. |
| * |
| * Map virtual address 'page' to physical address 'frame' |
| * using 'flags'. |
| * |
| * The address space must be locked and interruptsmust be disabled. |
| * |
| * @param as Address space to which page belongs. |
| * @param page Virtual address of the page to be mapped. |
| * @param frame Physical address of memory frame to which the mapping is done. |
| * @param flags Flags to be used for mapping. |
| */ |
| void ht_mapping_insert(as_t *as, __address page, __address frame, int flags) |
| { |
| pte_t *t, *u; |
| ipl_t ipl; |
| |
| ipl = interrupts_disable(); |
| spinlock_lock(&page_ht_lock); |
| |
| t = HT_HASH(page, as->asid); |
| if (!HT_SLOT_EMPTY(t)) { |
| |
| /* |
| * The slot is occupied. |
| * Walk through the collision chain and append the mapping to its end. |
| */ |
| |
| do { |
| u = t; |
| if (HT_COMPARE(page, as->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_RECORD(t, page, as->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. |
| * |
| * Find mapping for virtual page. |
| * |
| * The address space must be locked and interrupts must be disabled. |
| * |
| * @param as Address space to wich page belongs. |
| * @param page Virtual page. |
| * |
| * @return NULL if there is no such mapping; requested mapping otherwise. |
| */ |
| pte_t *ht_mapping_find(as_t *as, __address page) |
| { |
| pte_t *t; |
| |
| spinlock_lock(&page_ht_lock); |
| t = HT_HASH(page, as->asid); |
| if (!HT_SLOT_EMPTY(t)) { |
| while (!HT_COMPARE(page, as->asid, t) && HT_GET_NEXT(t)) |
| t = HT_GET_NEXT(t); |
| t = HT_COMPARE(page, as->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; |
| |
| 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); |
| } |