From f87a88642e660edd8912ad39fe77848c6f9927a2 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Fri, 5 Jun 2015 16:35:10 +1000 Subject: vfio: powerpc/spapr/iommu/powernv/ioda2: Rework IOMMU ownership control This adds tce_iommu_take_ownership() and tce_iommu_release_ownership which call in a loop iommu_take_ownership()/iommu_release_ownership() for every table on the group. As there is just one now, no change in behaviour is expected. At the moment the iommu_table struct has a set_bypass() which enables/ disables DMA bypass on IODA2 PHB. This is exposed to POWERPC IOMMU code which calls this callback when external IOMMU users such as VFIO are about to get over a PHB. The set_bypass() callback is not really an iommu_table function but IOMMU/PE function. This introduces a iommu_table_group_ops struct and adds take_ownership()/release_ownership() callbacks to it which are called when an external user takes/releases control over the IOMMU. This replaces set_bypass() with ownership callbacks as it is not necessarily just bypass enabling, it can be something else/more so let's give it more generic name. The callbacks is implemented for IODA2 only. Other platforms (P5IOC2, IODA1) will use the old iommu_take_ownership/iommu_release_ownership API. The following patches will replace iommu_take_ownership/ iommu_release_ownership calls in IODA2 with full IOMMU table release/ create. As we here and touching bypass control, this removes pnv_pci_ioda2_setup_bypass_pe() as it does not do much more compared to pnv_pci_ioda2_set_bypass. This moves tce_bypass_base initialization to pnv_pci_ioda2_setup_dma_pe. Signed-off-by: Alexey Kardashevskiy [aw: for the vfio related changes] Acked-by: Alex Williamson Reviewed-by: Gavin Shan Reviewed-by: David Gibson Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/iommu.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/include/asm/iommu.h') diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h index 44a20ccf06b4..489133cf7c5e 100644 --- a/arch/powerpc/include/asm/iommu.h +++ b/arch/powerpc/include/asm/iommu.h @@ -93,7 +93,6 @@ struct iommu_table { unsigned long it_page_shift;/* table iommu page size */ struct list_head it_group_list;/* List of iommu_table_group_link */ struct iommu_table_ops *it_ops; - void (*set_bypass)(struct iommu_table *tbl, bool enable); }; /* Pure 2^n version of get_order */ @@ -126,6 +125,15 @@ extern struct iommu_table *iommu_init_table(struct iommu_table * tbl, int nid); #define IOMMU_TABLE_GROUP_MAX_TABLES 1 +struct iommu_table_group; + +struct iommu_table_group_ops { + /* Switch ownership from platform code to external user (e.g. VFIO) */ + void (*take_ownership)(struct iommu_table_group *table_group); + /* Switch ownership from external user (e.g. VFIO) back to core */ + void (*release_ownership)(struct iommu_table_group *table_group); +}; + struct iommu_table_group_link { struct list_head next; struct rcu_head rcu; @@ -135,6 +143,7 @@ struct iommu_table_group_link { struct iommu_table_group { struct iommu_group *group; struct iommu_table *tables[IOMMU_TABLE_GROUP_MAX_TABLES]; + struct iommu_table_group_ops *ops; }; #ifdef CONFIG_IOMMU_API -- cgit v1.2.3