From 0ea22f072fb1b3da4307573c280ce904f0bf1589 Mon Sep 17 00:00:00 2001 From: Daniel De Graaf Date: Tue, 8 Feb 2011 09:14:06 -0500 Subject: xen-gntdev: Fix unmap notify on PV domains In paravirtualized guests, the struct page* for mappings is only a placeholder, and cannot be used to access the granted memory. Use the userspace mapping that we have set up in order to implement UNMAP_NOTIFY_CLEAR_BYTE. Signed-off-by: Daniel De Graaf Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/gntdev.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'drivers/xen/gntdev.c') diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 2aa8316..75f8037 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -289,7 +289,12 @@ static int unmap_grant_pages(struct grant_map *map, int offset, int pages) if (map->notify.flags & UNMAP_NOTIFY_CLEAR_BYTE) { int pgno = (map->notify.addr >> PAGE_SHIFT); - if (pgno >= offset && pgno < offset + pages) { + if (pgno >= offset && pgno < offset + pages && use_ptemod) { + void __user *tmp; + tmp = map->vma->vm_start + map->notify.addr; + copy_to_user(tmp, &err, 1); + map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE; + } else if (pgno >= offset && pgno < offset + pages) { uint8_t *tmp = kmap(map->pages[pgno]); tmp[map->notify.addr & (PAGE_SIZE-1)] = 0; kunmap(map->pages[pgno]); @@ -298,7 +303,7 @@ static int unmap_grant_pages(struct grant_map *map, int offset, int pages) } pr_debug("map %d+%d [%d+%d]\n", map->index, map->count, offset, pages); - err = gnttab_unmap_refs(map->unmap_ops + offset, map->pages, pages); + err = gnttab_unmap_refs(map->unmap_ops + offset, map->pages + offset, pages); if (err) return err; -- cgit v1.1