packagefs/package/CachedDataReader.cpp

34 	PagesDataOutput(vm_page** pages, size_t pageCount)
36 		fPages(pages),
172 	// check whether there are pages of the cache line and the mark them used
175 	vm_page* pages[kPagesPerCacheLine] = {};
184 	VMCachePagesTree::Iterator it = fCache->pages.GetIterator(pageOffset, true,
197 			// pages are missing
204 				pages[pageOffset - firstPageOffset] = NULL;
208 			pages[pageOffset++ - firstPageOffset] = page;
218 // TODO: If the missing pages range doesn't intersect with the request, just
220 		// There are pages of the cache line missing. We have to allocate fresh
227 			_DiscardPages(pages, firstMissing - firstPageOffset, missingPages);
234 		// Allocate the missing pages and remove the already existing pages in
240 			if (pages[index] == NULL) {
241 				pages[index] = vm_page_allocate_page(&reservation,
243 				DEBUG_PAGE_ACCESS_END(pages[index]);
246 				fCache->RemovePage(pages[index]);
253 		// add the pages to the cache
259 			fCache->InsertPage(pages[index], (off_t)pageOffset * B_PAGE_SIZE);
264 		// read in the missing pages
265 		status_t error = _ReadIntoPages(pages, firstMissing - firstPageOffset,
275 			_DiscardPages(pages, firstMissing - firstPageOffset, missingPages);
284 	status_t error = _WritePages(pages, requestOffset - lineOffset,
286 	_CachePages(pages, 0, linePageCount);
291 /*!	Frees all pages in given range of the \a pages array.
293 	to pages with \c PAGE_STATE_UNUSED. The pages may belong to \c fCache or
298 CachedDataReader::_DiscardPages(vm_page** pages, size_t firstPage,
307 		vm_page* page = pages[i];
324 /*!	Marks all pages in the given range of the \a pages array cached.
325 	There must not be any \c NULL entries in the given array range. All pages
330 CachedDataReader::_CachePages(vm_page** pages, size_t firstPage,
339 		vm_page* page = pages[i];
352 /*!	Writes the contents of pages in \c pages to \a output.
353 	\param pages The pages array.
354 	\param pagesRelativeOffset The offset relative to \a pages[0] where to
361 CachedDataReader::_WritePages(vm_page** pages, size_t pagesRelativeOffset,
371 	// fallback to copying individual pages
378 			pages[i]->physical_page_number * B_PAGE_SIZE, &address,
402 CachedDataReader::_ReadIntoPages(vm_page** pages, size_t firstPage,
405 	PagesDataOutput output(pages + firstPage, pageCount);
407 	off_t firstPageOffset = (off_t)pages[firstPage]->cache_offset