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 --- drivers/vfio/vfio_iommu_spapr_tce.c | 70 ++++++++++++++++++++++++++++++++++--- 1 file changed, 65 insertions(+), 5 deletions(-) (limited to 'drivers/vfio/vfio_iommu_spapr_tce.c') diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c index ffc634a75dba..9c720de46c33 100644 --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -486,6 +486,61 @@ static long tce_iommu_ioctl(void *iommu_data, return -ENOTTY; } +static void tce_iommu_release_ownership(struct tce_container *container, + struct iommu_table_group *table_group) +{ + int i; + + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { + struct iommu_table *tbl = table_group->tables[i]; + + if (!tbl) + continue; + + tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); + if (tbl->it_map) + iommu_release_ownership(tbl); + } +} + +static int tce_iommu_take_ownership(struct tce_container *container, + struct iommu_table_group *table_group) +{ + int i, j, rc = 0; + + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { + struct iommu_table *tbl = table_group->tables[i]; + + if (!tbl || !tbl->it_map) + continue; + + rc = iommu_take_ownership(tbl); + if (rc) { + for (j = 0; j < i; ++j) + iommu_release_ownership( + table_group->tables[j]); + + return rc; + } + } + + return 0; +} + +static void tce_iommu_release_ownership_ddw(struct tce_container *container, + struct iommu_table_group *table_group) +{ + table_group->ops->release_ownership(table_group); +} + +static long tce_iommu_take_ownership_ddw(struct tce_container *container, + struct iommu_table_group *table_group) +{ + table_group->ops->take_ownership(table_group); + + return 0; +} + static int tce_iommu_attach_group(void *iommu_data, struct iommu_group *iommu_group) { @@ -518,7 +573,12 @@ static int tce_iommu_attach_group(void *iommu_data, goto unlock_exit; } - ret = iommu_take_ownership(table_group->tables[0]); + if (!table_group->ops || !table_group->ops->take_ownership || + !table_group->ops->release_ownership) + ret = tce_iommu_take_ownership(container, table_group); + else + ret = tce_iommu_take_ownership_ddw(container, table_group); + if (!ret) container->grp = iommu_group; @@ -533,7 +593,6 @@ static void tce_iommu_detach_group(void *iommu_data, { struct tce_container *container = iommu_data; struct iommu_table_group *table_group; - struct iommu_table *tbl; mutex_lock(&container->lock); if (iommu_group != container->grp) { @@ -556,9 +615,10 @@ static void tce_iommu_detach_group(void *iommu_data, table_group = iommu_group_get_iommudata(iommu_group); BUG_ON(!table_group); - tbl = table_group->tables[0]; - tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); - iommu_release_ownership(tbl); + if (!table_group->ops || !table_group->ops->release_ownership) + tce_iommu_release_ownership(container, table_group); + else + tce_iommu_release_ownership_ddw(container, table_group); unlock_exit: mutex_unlock(&container->lock); -- cgit