Since there is now a mapping of granted pages in kernel address space in both PV and HVM, use it for UNMAP_NOTIFY_CLEAR_BYTE instead of accessing memory via copy_to_user and triggering sleep-in-atomic warnings.
Signed-off-by: Daniel De Graaf <[email protected]> --- drivers/xen/gntdev.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 9be3e5e..3c8803f 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -312,17 +312,10 @@ 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 && use_ptemod) { - void __user *tmp = (void __user *) - map->vma->vm_start + map->notify.addr; - err = copy_to_user(tmp, &err, 1); - if (err) - return -EFAULT; - map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE; - } else if (pgno >= offset && pgno < offset + pages) { - uint8_t *tmp = kmap(map->pages[pgno]); + if (pgno >= offset && pgno < offset + pages) { + /* No need for kmap, pages are in lowmem */ + uint8_t *tmp = pfn_to_kaddr(page_to_pfn(map->pages[pgno])); tmp[map->notify.addr & (PAGE_SIZE-1)] = 0; - kunmap(map->pages[pgno]); map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE; } } -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
