Index: kernel/generic/src/mm/as.c =================================================================== --- kernel/generic/src/mm/as.c (revision 49eb6818bdc4c8415ca4893642646cd5a99d5555) +++ kernel/generic/src/mm/as.c (revision cefb126edea34b0dd89c1d23a3945eba732448c8) @@ -116,9 +116,4 @@ as_t *AS_KERNEL = NULL; -static unsigned int area_flags_to_page_flags(unsigned int); -static as_area_t *find_area_and_lock(as_t *, uintptr_t); -static bool check_area_conflicts(as_t *, uintptr_t, size_t, as_area_t *); -static void sh_info_remove_reference(share_info_t *); - static int as_constructor(void *obj, unsigned int flags) { @@ -296,4 +291,104 @@ if (atomic_predec(&as->refcount) == 0) as_destroy(as); +} + +/** Check area conflicts with other areas. + * + * @param as Address space. + * @param va Starting virtual address of the area being tested. + * @param size Size of the area being tested. + * @param avoid_area Do not touch this area. + * + * @return True if there is no conflict, false otherwise. + * + */ +static bool check_area_conflicts(as_t *as, uintptr_t va, size_t size, + as_area_t *avoid_area) +{ + ASSERT(mutex_locked(&as->lock)); + + /* + * We don't want any area to have conflicts with NULL page. + * + */ + if (overlaps(va, size, NULL, PAGE_SIZE)) + return false; + + /* + * The leaf node is found in O(log n), where n is proportional to + * the number of address space areas belonging to as. + * The check for conflicts is then attempted on the rightmost + * record in the left neighbour, the leftmost record in the right + * neighbour and all records in the leaf node itself. + * + */ + btree_node_t *leaf; + as_area_t *area = + (as_area_t *) btree_search(&as->as_area_btree, va, &leaf); + if (area) { + if (area != avoid_area) + return false; + } + + /* First, check the two border cases. */ + btree_node_t *node = + btree_leaf_node_left_neighbour(&as->as_area_btree, leaf); + if (node) { + area = (as_area_t *) node->value[node->keys - 1]; + + mutex_lock(&area->lock); + + if (overlaps(va, size, area->base, area->pages * PAGE_SIZE)) { + mutex_unlock(&area->lock); + return false; + } + + mutex_unlock(&area->lock); + } + + node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf); + if (node) { + area = (as_area_t *) node->value[0]; + + mutex_lock(&area->lock); + + if (overlaps(va, size, area->base, area->pages * PAGE_SIZE)) { + mutex_unlock(&area->lock); + return false; + } + + mutex_unlock(&area->lock); + } + + /* Second, check the leaf node. */ + btree_key_t i; + for (i = 0; i < leaf->keys; i++) { + area = (as_area_t *) leaf->value[i]; + + if (area == avoid_area) + continue; + + mutex_lock(&area->lock); + + if (overlaps(va, size, area->base, area->pages * PAGE_SIZE)) { + mutex_unlock(&area->lock); + return false; + } + + mutex_unlock(&area->lock); + } + + /* + * So far, the area does not conflict with other areas. + * Check if it doesn't conflict with kernel address space. + * + */ + if (!KERNEL_ADDRESS_SPACE_SHADOWED) { + return !overlaps(va, size, + KERNEL_ADDRESS_SPACE_START, + KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START); + } + + return true; } @@ -357,4 +452,66 @@ return area; +} + +/** Find address space area and lock it. + * + * @param as Address space. + * @param va Virtual address. + * + * @return Locked address space area containing va on success or + * NULL on failure. + * + */ +static as_area_t *find_area_and_lock(as_t *as, uintptr_t va) +{ + ASSERT(mutex_locked(&as->lock)); + + btree_node_t *leaf; + as_area_t *area = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf); + if (area) { + /* va is the base address of an address space area */ + mutex_lock(&area->lock); + return area; + } + + /* + * Search the leaf node and the righmost record of its left neighbour + * to find out whether this is a miss or va belongs to an address + * space area found there. + * + */ + + /* First, search the leaf node itself. */ + btree_key_t i; + + for (i = 0; i < leaf->keys; i++) { + area = (as_area_t *) leaf->value[i]; + + mutex_lock(&area->lock); + + if ((area->base <= va) && (va < area->base + area->pages * PAGE_SIZE)) + return area; + + mutex_unlock(&area->lock); + } + + /* + * Second, locate the left neighbour and test its last record. + * Because of its position in the B+tree, it must have base < va. + * + */ + btree_node_t *lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf); + if (lnode) { + area = (as_area_t *) lnode->value[lnode->keys - 1]; + + mutex_lock(&area->lock); + + if (va < area->base + area->pages * PAGE_SIZE) + return area; + + mutex_unlock(&area->lock); + } + + return NULL; } @@ -553,4 +710,45 @@ } +/** Remove reference to address space area share info. + * + * If the reference count drops to 0, the sh_info is deallocated. + * + * @param sh_info Pointer to address space area share info. + * + */ +static void sh_info_remove_reference(share_info_t *sh_info) +{ + bool dealloc = false; + + mutex_lock(&sh_info->lock); + ASSERT(sh_info->refcount); + + if (--sh_info->refcount == 0) { + dealloc = true; + link_t *cur; + + /* + * Now walk carefully the pagemap B+tree and free/remove + * reference from all frames found there. + */ + for (cur = sh_info->pagemap.leaf_head.next; + cur != &sh_info->pagemap.leaf_head; cur = cur->next) { + btree_node_t *node + = list_get_instance(cur, btree_node_t, leaf_link); + btree_key_t i; + + for (i = 0; i < node->keys; i++) + frame_free((uintptr_t) node->value[i]); + } + + } + mutex_unlock(&sh_info->lock); + + if (dealloc) { + btree_destroy(&sh_info->pagemap); + free(sh_info); + } +} + /** Destroy address space area. * @@ -805,4 +1003,30 @@ } +/** Convert address space area flags to page flags. + * + * @param aflags Flags of some address space area. + * + * @return Flags to be passed to page_mapping_insert(). + * + */ +static unsigned int area_flags_to_page_flags(unsigned int aflags) +{ + unsigned int flags = PAGE_USER | PAGE_PRESENT; + + if (aflags & AS_AREA_READ) + flags |= PAGE_READ; + + if (aflags & AS_AREA_WRITE) + flags |= PAGE_WRITE; + + if (aflags & AS_AREA_EXEC) + flags |= PAGE_EXEC; + + if (aflags & AS_AREA_CACHEABLE) + flags |= PAGE_CACHEABLE; + + return flags; +} + /** Change adress space area flags. * @@ -1161,29 +1385,5 @@ } -/** Convert address space area flags to page flags. - * - * @param aflags Flags of some address space area. - * - * @return Flags to be passed to page_mapping_insert(). - * - */ -unsigned int area_flags_to_page_flags(unsigned int aflags) -{ - unsigned int flags = PAGE_USER | PAGE_PRESENT; - - if (aflags & AS_AREA_READ) - flags |= PAGE_READ; - - if (aflags & AS_AREA_WRITE) - flags |= PAGE_WRITE; - - if (aflags & AS_AREA_EXEC) - flags |= PAGE_EXEC; - - if (aflags & AS_AREA_CACHEABLE) - flags |= PAGE_CACHEABLE; - - return flags; -} + /** Compute flags for virtual address translation subsytem. @@ -1272,8 +1472,8 @@ /** Test whether page tables are locked. * - * @param as Address space where the page tables belong. - * - * @return True if the page tables belonging to the address soace - * are locked, otherwise false. + * @param as Address space where the page tables belong. + * + * @return True if the page tables belonging to the address soace + * are locked, otherwise false. */ bool page_table_locked(as_t *as) @@ -1283,167 +1483,4 @@ return as_operations->page_table_locked(as); -} - - -/** Find address space area and lock it. - * - * @param as Address space. - * @param va Virtual address. - * - * @return Locked address space area containing va on success or - * NULL on failure. - * - */ -as_area_t *find_area_and_lock(as_t *as, uintptr_t va) -{ - ASSERT(mutex_locked(&as->lock)); - - btree_node_t *leaf; - as_area_t *area = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf); - if (area) { - /* va is the base address of an address space area */ - mutex_lock(&area->lock); - return area; - } - - /* - * Search the leaf node and the righmost record of its left neighbour - * to find out whether this is a miss or va belongs to an address - * space area found there. - * - */ - - /* First, search the leaf node itself. */ - btree_key_t i; - - for (i = 0; i < leaf->keys; i++) { - area = (as_area_t *) leaf->value[i]; - - mutex_lock(&area->lock); - - if ((area->base <= va) && (va < area->base + area->pages * PAGE_SIZE)) - return area; - - mutex_unlock(&area->lock); - } - - /* - * Second, locate the left neighbour and test its last record. - * Because of its position in the B+tree, it must have base < va. - * - */ - btree_node_t *lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf); - if (lnode) { - area = (as_area_t *) lnode->value[lnode->keys - 1]; - - mutex_lock(&area->lock); - - if (va < area->base + area->pages * PAGE_SIZE) - return area; - - mutex_unlock(&area->lock); - } - - return NULL; -} - -/** Check area conflicts with other areas. - * - * @param as Address space. - * @param va Starting virtual address of the area being tested. - * @param size Size of the area being tested. - * @param avoid_area Do not touch this area. - * - * @return True if there is no conflict, false otherwise. - * - */ -bool check_area_conflicts(as_t *as, uintptr_t va, size_t size, - as_area_t *avoid_area) -{ - ASSERT(mutex_locked(&as->lock)); - - /* - * We don't want any area to have conflicts with NULL page. - * - */ - if (overlaps(va, size, NULL, PAGE_SIZE)) - return false; - - /* - * The leaf node is found in O(log n), where n is proportional to - * the number of address space areas belonging to as. - * The check for conflicts is then attempted on the rightmost - * record in the left neighbour, the leftmost record in the right - * neighbour and all records in the leaf node itself. - * - */ - btree_node_t *leaf; - as_area_t *area = - (as_area_t *) btree_search(&as->as_area_btree, va, &leaf); - if (area) { - if (area != avoid_area) - return false; - } - - /* First, check the two border cases. */ - btree_node_t *node = - btree_leaf_node_left_neighbour(&as->as_area_btree, leaf); - if (node) { - area = (as_area_t *) node->value[node->keys - 1]; - - mutex_lock(&area->lock); - - if (overlaps(va, size, area->base, area->pages * PAGE_SIZE)) { - mutex_unlock(&area->lock); - return false; - } - - mutex_unlock(&area->lock); - } - - node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf); - if (node) { - area = (as_area_t *) node->value[0]; - - mutex_lock(&area->lock); - - if (overlaps(va, size, area->base, area->pages * PAGE_SIZE)) { - mutex_unlock(&area->lock); - return false; - } - - mutex_unlock(&area->lock); - } - - /* Second, check the leaf node. */ - btree_key_t i; - for (i = 0; i < leaf->keys; i++) { - area = (as_area_t *) leaf->value[i]; - - if (area == avoid_area) - continue; - - mutex_lock(&area->lock); - - if (overlaps(va, size, area->base, area->pages * PAGE_SIZE)) { - mutex_unlock(&area->lock); - return false; - } - - mutex_unlock(&area->lock); - } - - /* - * So far, the area does not conflict with other areas. - * Check if it doesn't conflict with kernel address space. - * - */ - if (!KERNEL_ADDRESS_SPACE_SHADOWED) { - return !overlaps(va, size, - KERNEL_ADDRESS_SPACE_START, - KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START); - } - - return true; } @@ -1960,45 +1997,4 @@ } -/** Remove reference to address space area share info. - * - * If the reference count drops to 0, the sh_info is deallocated. - * - * @param sh_info Pointer to address space area share info. - * - */ -void sh_info_remove_reference(share_info_t *sh_info) -{ - bool dealloc = false; - - mutex_lock(&sh_info->lock); - ASSERT(sh_info->refcount); - - if (--sh_info->refcount == 0) { - dealloc = true; - link_t *cur; - - /* - * Now walk carefully the pagemap B+tree and free/remove - * reference from all frames found there. - */ - for (cur = sh_info->pagemap.leaf_head.next; - cur != &sh_info->pagemap.leaf_head; cur = cur->next) { - btree_node_t *node - = list_get_instance(cur, btree_node_t, leaf_link); - btree_key_t i; - - for (i = 0; i < node->keys; i++) - frame_free((uintptr_t) node->value[i]); - } - - } - mutex_unlock(&sh_info->lock); - - if (dealloc) { - btree_destroy(&sh_info->pagemap); - free(sh_info); - } -} - /* * Address space related syscalls. Index: kernel/generic/src/mm/page.c =================================================================== --- kernel/generic/src/mm/page.c (revision 49eb6818bdc4c8415ca4893642646cd5a99d5555) +++ kernel/generic/src/mm/page.c (revision cefb126edea34b0dd89c1d23a3945eba732448c8) @@ -38,5 +38,5 @@ * mappings between virtual addresses and physical addresses. * Functions here are mere wrappers that call the real implementation. - * They however, define the single interface. + * They however, define the single interface. * */