From 8da7633f168b5428e2cfb7342408b2c44088f5df Mon Sep 17 00:00:00 2001 From: Jennifer Herbert Date: Wed, 24 Dec 2014 14:17:06 +0000 Subject: xen: mark grant mapped pages as foreign Use the "foreign" page flag to mark pages that have a grant map. Use page->private to store information of the grant (the granting domain and the grant reference). Signed-off-by: Jennifer Herbert Reviewed-by: Stefano Stabellini Signed-off-by: David Vrabel --- drivers/xen/grant-table.c | 43 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 41 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index b4f93c490f83..89dcca448bb6 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -679,12 +679,27 @@ EXPORT_SYMBOL_GPL(gnttab_free_auto_xlat_frames); */ int gnttab_alloc_pages(int nr_pages, struct page **pages) { + int i; int ret; ret = alloc_xenballooned_pages(nr_pages, pages, false); if (ret < 0) return ret; + for (i = 0; i < nr_pages; i++) { +#if BITS_PER_LONG < 64 + struct xen_page_foreign *foreign; + + foreign = kzalloc(sizeof(*foreign), GFP_KERNEL); + if (!foreign) { + gnttab_free_pages(nr_pages, pages); + return -ENOMEM; + } + set_page_private(pages[i], (unsigned long)foreign); +#endif + SetPagePrivate(pages[i]); + } + return 0; } EXPORT_SYMBOL(gnttab_alloc_pages); @@ -696,6 +711,16 @@ EXPORT_SYMBOL(gnttab_alloc_pages); */ void gnttab_free_pages(int nr_pages, struct page **pages) { + int i; + + for (i = 0; i < nr_pages; i++) { + if (PagePrivate(pages[i])) { +#if BITS_PER_LONG < 64 + kfree((void *)page_private(pages[i])); +#endif + ClearPagePrivate(pages[i]); + } + } free_xenballooned_pages(nr_pages, pages); } EXPORT_SYMBOL(gnttab_free_pages); @@ -756,12 +781,22 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, if (ret) return ret; - /* Retry eagain maps */ - for (i = 0; i < count; i++) + for (i = 0; i < count; i++) { + /* Retry eagain maps */ if (map_ops[i].status == GNTST_eagain) gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, map_ops + i, &map_ops[i].status, __func__); + if (map_ops[i].status == GNTST_okay) { + struct xen_page_foreign *foreign; + + SetPageForeign(pages[i]); + foreign = xen_page_foreign(pages[i]); + foreign->domid = map_ops[i].dom; + foreign->gref = map_ops[i].ref; + } + } + return set_foreign_p2m_mapping(map_ops, kmap_ops, pages, count); } EXPORT_SYMBOL_GPL(gnttab_map_refs); @@ -770,12 +805,16 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, struct gnttab_unmap_grant_ref *kunmap_ops, struct page **pages, unsigned int count) { + unsigned int i; int ret; ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap_ops, count); if (ret) return ret; + for (i = 0; i < count; i++) + ClearPageForeign(pages[i]); + return clear_foreign_p2m_mapping(unmap_ops, kunmap_ops, pages, count); } EXPORT_SYMBOL_GPL(gnttab_unmap_refs); -- cgit v1.2.3