From 087ffecdaa1875cc683a7a5bc0695b3ebfce3bad Mon Sep 17 00:00:00 2001 From: Roger Pau Monne Date: Thu, 14 Feb 2013 11:12:09 +0100 Subject: [PATCH] xen-blkback: use balloon pages for persistent grants MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit With current persistent grants implementation we are not freeing the persistent grants after we disconnect the device. Since grant map operations change the mfn of the allocated page, and we can no longer pass it to __free_page without setting the mfn to a sane value, use balloon grant pages instead, as the gntdev device does. Signed-off-by: Roger Pau Monné Cc: stable@vger.kernel.org Cc: Konrad Rzeszutek Wilk Signed-off-by: Konrad Rzeszutek Wilk --- drivers/block/xen-blkback/blkback.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 1966a7cfd8ce..de1f319f7bd7 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -46,6 +46,7 @@ #include #include #include +#include #include "common.h" /* @@ -239,6 +240,7 @@ static void free_persistent_gnts(struct rb_root *root, unsigned int num) ret = gnttab_unmap_refs(unmap, NULL, pages, segs_to_unmap); BUG_ON(ret); + free_xenballooned_pages(segs_to_unmap, pages); segs_to_unmap = 0; } @@ -527,8 +529,8 @@ static int xen_blkbk_map(struct blkif_request *req, GFP_KERNEL); if (!persistent_gnt) return -ENOMEM; - persistent_gnt->page = alloc_page(GFP_KERNEL); - if (!persistent_gnt->page) { + if (alloc_xenballooned_pages(1, &persistent_gnt->page, + false)) { kfree(persistent_gnt); return -ENOMEM; } -- 2.20.1