vm_page_allocate_page_run(): Added parameter "limit", specifying the upper

physical address limit for the page run to allocate.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37086 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/vm/vm_page.h

@@ -61,7 +61,7 @@ bool vm_page_try_reserve_pages(vm_page_reservation* reservation, uint32 count,
 struct vm_page *vm_page_allocate_page(vm_page_reservation* reservation,
 	uint32 flags);
 struct vm_page *vm_page_allocate_page_run(uint32 flags, phys_addr_t base,
-	page_num_t length, int priority);
+	phys_addr_t limit, page_num_t length, int priority);
 struct vm_page *vm_page_at_index(int32 index);
 struct vm_page *vm_lookup_page(page_num_t pageNumber);
 bool vm_page_is_dummy(struct vm_page *page);

src/add-ons/kernel/bus_managers/agp_gart/agp_gart.cpp

@@ -540,7 +540,7 @@ Aperture::AllocateMemory(aperture_memory *memory, uint32 flags)
 
 	if ((flags & B_APERTURE_NEED_PHYSICAL) != 0) {
 		memory->page = vm_page_allocate_page_run(
-			PAGE_STATE_WIRED | VM_PAGE_ALLOC_CLEAR, 0, count,
+			PAGE_STATE_WIRED | VM_PAGE_ALLOC_CLEAR, 0, 0, count,
 			VM_PRIORITY_SYSTEM);
 		if (memory->page == NULL)
 			return B_NO_MEMORY;

src/system/kernel/vm/vm.cpp

@@ -1181,7 +1181,7 @@ vm_create_anonymous_area(team_id team, const char* name, void** address,
 		// we try to allocate the page run here upfront as this may easily
 		// fail for obvious reasons
 		page = vm_page_allocate_page_run(PAGE_STATE_WIRED | pageAllocFlags,
-			physicalAddress, size / B_PAGE_SIZE, priority);
+			physicalAddress, 0, size / B_PAGE_SIZE, priority);
 		if (page == NULL) {
 			status = B_NO_MEMORY;
 			goto err0;

src/system/kernel/vm/vm_page.cpp

@@ -3319,11 +3319,30 @@ allocate_page_run(page_num_t start, page_num_t length, uint32 flags,
 }
 
 
-vm_page *
-vm_page_allocate_page_run(uint32 flags, phys_addr_t base, page_num_t length,
-	int priority)
+/*! Allocate a physically contiguous range of pages.
+
+	\param flags Page allocation flags. Encodes the state the function shall
+		set the allocated pages to, whether the pages shall be marked busy
+		(VM_PAGE_ALLOC_BUSY), and whether the pages shall be cleared
+		(VM_PAGE_ALLOC_CLEAR).
+	\param base The first acceptable physical address where the page run may
+		start.
+	\param limit The last acceptable physical address where the page run may
+		end (i.e. it must hold runStartAddress + runSize <= limit). If \c 0,
+		the limit is ignored.
+	\param length The number of contiguous pages to allocate.
+	\param priority The page reservation priority (as passed to
+		vm_page_reserve_pages()).
+	\return The first page of the allocated page run on success; \c NULL
+		when the allocation failed.
+*/
+vm_page*
+vm_page_allocate_page_run(uint32 flags, phys_addr_t base, phys_addr_t limit,
+	page_num_t length, int priority)
 {
-	page_num_t start = base >> PAGE_SHIFT;
+	page_num_t start = base / B_PAGE_SIZE;
+	page_num_t end = std::min(limit > 0 ? limit / B_PAGE_SIZE : sNumPages,
+		sNumPages);
 
 	vm_page_reservation reservation;
 	vm_page_reserve_pages(&reservation, length, priority);
@@ -3338,8 +3357,7 @@ vm_page_allocate_page_run(uint32 flags, phys_addr_t base, page_num_t length,
 	int useCached = freePages > 0 && (page_num_t)freePages > 2 * length ? 0 : 1;
 
 	for (;;) {
-		bool foundRun = true;
-		if (start + length > sNumPages) {
+		if (start + length > end) {
 			if (useCached == 0) {
 				// The first iteration with free pages only was unsuccessful.
 				// Try again also considering cached pages.
@@ -3356,6 +3374,7 @@ vm_page_allocate_page_run(uint32 flags, phys_addr_t base, page_num_t length,
 			return NULL;
 		}
 
+		bool foundRun = true;
 		page_num_t i;
 		for (i = 0; i < length; i++) {
 			uint32 pageState = sPages[start + i].State();