block/xen-blkback/blkback.c

56  * Maximum number of unused free pages to keep in the internal buffer.
68 "Maximum number of free pages to keep in each block backend buffer");
109  * Maximum order of pages to be used for the shared ring between front and
114 MODULE_PARM_DESC(max_ring_page_order, "Maximum order of pages to be used for the shared ring");
246 	struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST];
255 	unmap_data.pages = pages;
268 		pages[segs_to_unmap] = persistent_gnt->page;
276 			gnttab_page_cache_put(&ring->free_pages, pages,
293 	struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST];
299 	unmap_data.pages = pages;
314 		pages[segs_to_unmap] = persistent_gnt->page;
319 			gnttab_page_cache_put(&ring->free_pages, pages,
328 		gnttab_page_cache_put(&ring->free_pages, pages, segs_to_unmap);
611 		/* Shrink the free pages pool if it is too large. */
634  * Remove persistent grants and empty the pool of free pages
638 	/* Free all persistent grant pages */
641 	/* Since we are shutting down remove all pages from the buffer */
647 	struct grant_page **pages,
655 		if (pages[i]->persistent_gnt != NULL) {
656 			put_persistent_gnt(ring, pages[i]->persistent_gnt);
659 		if (pages[i]->handle == BLKBACK_INVALID_HANDLE)
661 		unmap_pages[invcount] = pages[i]->page;
662 		gnttab_set_unmap_op(&unmap_ops[invcount], vaddr(pages[i]->page),
663 				    GNTMAP_host_map, pages[i]->handle);
664 		pages[i]->handle = BLKBACK_INVALID_HANDLE;
681 	gnttab_page_cache_put(&ring->free_pages, data->pages, data->count);
707 	struct grant_page **pages = req->segments;
710 	invcount = xen_blkbk_unmap_prepare(ring, pages, req->nr_segs,
717 	work->pages = req->unmap_pages;
732                             struct grant_page *pages[],
743 		invcount = xen_blkbk_unmap_prepare(ring, pages, batch,
751 		pages += batch;
757 			 struct grant_page *pages[],
785 				pages[i]->gref);
793 			pages[i]->page = persistent_gnt->page;
794 			pages[i]->persistent_gnt = persistent_gnt;
797 						  &pages[i]->page)) {
804 			addr = vaddr(pages[i]->page);
805 			pages_to_gnt[segs_to_map] = pages[i]->page;
806 			pages[i]->persistent_gnt = NULL;
811 					  flags, pages[i]->gref,
828 		if (!pages[seg_idx]->persistent_gnt) {
834 						      &pages[seg_idx]->page, 1);
835 				pages[seg_idx]->handle = BLKBACK_INVALID_HANDLE;
839 			pages[seg_idx]->handle = map[new_map_idx].handle;
861 			persistent_gnt->page = pages[seg_idx]->page;
868 			pages[seg_idx]->persistent_gnt = persistent_gnt;
895 			pages[i]->persistent_gnt = NULL;
896 		pages[i]->handle = BLKBACK_INVALID_HANDLE;
918 	struct grant_page **pages = pending_req->indirect_pages;
928 		pages[i]->gref = req->u.indirect.indirect_grefs[i];
930 	rc = xen_blkbk_map(ring, pages, indirect_grefs, true);
941 			segments = kmap_atomic(pages[n/SEGS_PER_INDIRECT_FRAME]->page);
962 	xen_blkbk_unmap(ring, pages, indirect_grefs);
1304 	struct grant_page **pages = pending_req->segments;
1367 			pages[i]->gref = req->u.rw.seg[i].gref;
1431 				     pages[i]->page,