From e5afdf9dd515a9446c009f44f99f9bc2f91b89a7 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Wed, 22 Mar 2017 15:21:50 +1100 Subject: powerpc/vfio_spapr_tce: Add reference counting to iommu_table So far iommu_table obejcts were only used in virtual mode and had a single owner. We are going to change this by implementing in-kernel acceleration of DMA mapping requests. The proposed acceleration will handle requests in real mode and KVM will keep references to tables. This adds a kref to iommu_table and defines new helpers to update it. This replaces iommu_free_table() with iommu_tce_table_put() and makes iommu_free_table() static. iommu_tce_table_get() is not used in this patch but it will be in the following patch. Since this touches prototypes, this also removes @node_name parameter as it has never been really useful on powernv and carrying it for the pseries platform code to iommu_free_table() seems to be quite useless as well. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Acked-by: Alex Williamson Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/pseries/iommu.c | 3 ++- arch/powerpc/platforms/pseries/vio.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/platforms/pseries') diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index 4d757eaa46bf..7ce5db209abf 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -74,6 +74,7 @@ static struct iommu_table_group *iommu_pseries_alloc_group(int node) goto fail_exit; INIT_LIST_HEAD_RCU(&tbl->it_group_list); + kref_init(&tbl->it_kref); tgl->table_group = table_group; list_add_rcu(&tgl->next, &tbl->it_group_list); @@ -115,7 +116,7 @@ static void iommu_pseries_free_group(struct iommu_table_group *table_group, BUG_ON(table_group->group); } #endif - iommu_free_table(tbl, node_name); + iommu_tce_table_put(tbl); kfree(table_group); } diff --git a/arch/powerpc/platforms/pseries/vio.c b/arch/powerpc/platforms/pseries/vio.c index 720493932486..28b09fd797ec 100644 --- a/arch/powerpc/platforms/pseries/vio.c +++ b/arch/powerpc/platforms/pseries/vio.c @@ -1318,7 +1318,7 @@ static void vio_dev_release(struct device *dev) struct iommu_table *tbl = get_iommu_table_base(dev); if (tbl) - iommu_free_table(tbl, of_node_full_name(dev->of_node)); + iommu_tce_table_put(tbl); of_node_put(dev->of_node); kfree(to_vio_dev(dev)); } -- cgit v1.2.3