This defines and implements VFIO IOMMU API required to support
Dynamic DMA windows defined in the SPAPR specification. The ioctl handlers
implement host-size part of corresponding RTAS calls:
- VFIO_IOMMU_SPAPR_TCE_QUERY - ibm,query-pe-dma-window;
- VFIO_IOMMU_SPAPR_TCE_CREATE - ibm,create-pe-dma-window;
- VFIO_IOMMU_SPAPR_TCE_REMOVE - ibm,remove-pe-dma-window;
- VFIO_IOMMU_SPAPR_TCE_RESET - ibm,reset-pe-dma-window.
The VFIO IOMMU driver does basic sanity checks and calls corresponding
SPAPR TCE functions. At the moment only IODA2 (POWER8 PCI host bridge)
implements them.
This advertises VFIO_IOMMU_SPAPR_TCE_FLAG_DDW capability via
VFIO_IOMMU_SPAPR_TCE_GET_INFO.
This calls reset() when IOMMU is being disabled (happens when VFIO stops
using it).
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
arch/powerpc/platforms/powernv/pci-ioda.c | 1 +
drivers/vfio/vfio_iommu_spapr_tce.c | 173 +++++++++++++++++++++++++++++-
include/uapi/linux/vfio.h | 37 ++++++-
3 files changed, 209 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c
b/arch/powerpc/platforms/powernv/pci-ioda.c
index 6a847b2..f51afe2 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -859,6 +859,7 @@ static long pnv_pci_ioda2_ddw_create(struct
spapr_tce_iommu_group *data,
/* Copy "invalidate" register address */
tbl64->it_index = pe->tce32.table.it_index;
+ tbl64->it_group = pe->tce32.table.it_group;
tbl64->it_type = TCE_PCI_SWINV_CREATE | TCE_PCI_SWINV_FREE |
TCE_PCI_SWINV_PAIR;
tbl64->it_map = (void *) 0xDEADBEEF; /* poison */
diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c
b/drivers/vfio/vfio_iommu_spapr_tce.c
index 48b256c..32e2804 100644
--- a/drivers/vfio/vfio_iommu_spapr_tce.c
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -45,6 +45,7 @@ struct tce_container {
struct mutex lock;
struct iommu_group *grp;
bool enabled;
+ unsigned long start64;
};
@@ -123,19 +124,36 @@ static void tce_iommu_disable(struct tce_container
*container)
container->enabled = false;
- if (!container->grp || !current->mm)
+ if (!container->grp)
return;
data = iommu_group_get_iommudata(container->grp);
if (!data || !data->iommu_owner || !data->ops->get_table)
return;
+ /* Try resetting, there might have been a 64bit window */
+ if (data->ops->reset)
+ data->ops->reset(data);
+
+ if (!current->mm)
+ return;
+
tbl = data->ops->get_table(data, TCE_DEFAULT_WINDOW);
if (!tbl)
return;
decrement_locked_vm((tbl->it_size << tbl->it_page_shift) >>
PAGE_SHIFT);
+
+ if (!container->start64)
+ return;
+
+ tbl = data->ops->get_table(data, container->start64);
+ if (!tbl)
+ return;
+
+ decrement_locked_vm((tbl->it_size << tbl->it_page_shift) >>
+ PAGE_SHIFT);
}
static void *tce_iommu_open(unsigned long arg)
@@ -210,6 +228,8 @@ static long tce_iommu_ioctl(void *iommu_data,
info.dma32_window_start = tbl->it_offset << tbl->it_page_shift;
info.dma32_window_size = tbl->it_size << tbl->it_page_shift;
info.flags = 0;
+ if (data->ops->query && data->ops->create && data->ops->remove)
+ info.flags |= VFIO_IOMMU_SPAPR_TCE_FLAG_DDW;
if (copy_to_user((void __user *)arg, &info, minsz))
return -EFAULT;
@@ -335,6 +355,157 @@ static long tce_iommu_ioctl(void *iommu_data,
tce_iommu_disable(container);
mutex_unlock(&container->lock);
return 0;
+
+ case VFIO_IOMMU_SPAPR_TCE_QUERY: {
+ struct vfio_iommu_spapr_tce_query query;
+ struct spapr_tce_iommu_group *data;
+
+ if (WARN_ON(!container->grp))
+ return -ENXIO;
+
+ data = iommu_group_get_iommudata(container->grp);
+
+ minsz = offsetofend(struct vfio_iommu_spapr_tce_query,
+ page_size_mask);
+
+ if (copy_from_user(&query, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (query.argsz < minsz)
+ return -EINVAL;
+
+ if (!data->ops->query || !data->iommu_owner)
+ return -ENOSYS;
+
+ ret = data->ops->query(data,
+ &query.windows_available,
+ &query.page_size_mask);
+
+ if (ret)
+ return ret;
+
+ if (copy_to_user((void __user *)arg, &query, minsz))
+ return -EFAULT;
+
+ return 0;
+ }
+ case VFIO_IOMMU_SPAPR_TCE_CREATE: {
+ struct vfio_iommu_spapr_tce_create create;
+ struct spapr_tce_iommu_group *data;
+ struct iommu_table *tbl;
+
+ if (WARN_ON(!container->grp))
+ return -ENXIO;
+
+ data = iommu_group_get_iommudata(container->grp);
+
+ minsz = offsetofend(struct vfio_iommu_spapr_tce_create,
+ start_addr);
+
+ if (copy_from_user(&create, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (create.argsz < minsz)
+ return -EINVAL;
+
+ if (!data->ops->create || !data->iommu_owner)
+ return -ENOSYS;
+
+ BUG_ON(!data || !data->ops || !data->ops->remove);
+
+ ret = data->ops->create(data, create.page_shift,
+ create.window_shift, &tbl);
+ if (ret)
+ return ret;
+
+ ret = try_increment_locked_vm((tbl->it_size <<
+ tbl->it_page_shift) >> PAGE_SHIFT);
+ if (ret) {
+ data->ops->remove(data, tbl);
+ return ret;
+ }
+
+ create.start_addr = tbl->it_offset << tbl->it_page_shift;
+
+ if (copy_to_user((void __user *)arg, &create, minsz)) {
+ data->ops->remove(data, tbl);
+ decrement_locked_vm((tbl->it_size <<
+ tbl->it_page_shift) >> PAGE_SHIFT);
+ return -EFAULT;
+ }
+
+ return ret;
+ }
+ case VFIO_IOMMU_SPAPR_TCE_REMOVE: {
+ struct vfio_iommu_spapr_tce_remove remove;
+ struct spapr_tce_iommu_group *data;
+ struct iommu_table *tbl;
+
+ if (WARN_ON(!container->grp))
+ return -ENXIO;
+
+ data = iommu_group_get_iommudata(container->grp);
+
+ minsz = offsetofend(struct vfio_iommu_spapr_tce_remove,
+ start_addr);
+
+ if (copy_from_user(&remove, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (remove.argsz < minsz)
+ return -EINVAL;
+
+ if (!data->ops->remove || !data->iommu_owner)
+ return -ENOSYS;
+
+ tbl = data->ops->get_table(data, remove.start_addr);
+ if (!tbl)
+ return -EINVAL;
+
+ ret = data->ops->remove(data, tbl);
+ if (ret)
+ return ret;
+
+ decrement_locked_vm((tbl->it_size << tbl->it_page_shift)
+ >> PAGE_SHIFT);
+ return 0;
+ }
+ case VFIO_IOMMU_SPAPR_TCE_RESET: {
+ struct vfio_iommu_spapr_tce_reset reset;
+ struct spapr_tce_iommu_group *data;
+
+ if (WARN_ON(!container->grp))
+ return -ENXIO;
+
+ data = iommu_group_get_iommudata(container->grp);
+
+ minsz = offsetofend(struct vfio_iommu_spapr_tce_reset, argsz);
+
+ if (copy_from_user(&reset, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (reset.argsz < minsz)
+ return -EINVAL;
+
+ if (!data->ops->reset || !data->iommu_owner)
+ return -ENOSYS;
+
+ ret = data->ops->reset(data);
+ if (ret)
+ return ret;
+
+ if (container->start64) {
+ struct iommu_table *tbl;
+
+ tbl = data->ops->get_table(data, container->start64);
+ BUG_ON(!tbl);
+
+ decrement_locked_vm((tbl->it_size << tbl->it_page_shift)
+ >> PAGE_SHIFT);
+ }
+
+ return 0;
+ }
}
return -ENOTTY;
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index cb9023d..8b03381 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -448,13 +448,48 @@ struct vfio_iommu_type1_dma_unmap {
*/
struct vfio_iommu_spapr_tce_info {
__u32 argsz;
- __u32 flags; /* reserved for future use */
+ __u32 flags;
+#define VFIO_IOMMU_SPAPR_TCE_FLAG_DDW 1 /* Support dynamic windows */
__u32 dma32_window_start; /* 32 bit window start (bytes) */
__u32 dma32_window_size; /* 32 bit window size (bytes) */
};
#define VFIO_IOMMU_SPAPR_TCE_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12)
+/*
+ * Dynamic DMA windows
+ */
+struct vfio_iommu_spapr_tce_query {
+ __u32 argsz;
+ /* out */
+ __u32 windows_available;
+ __u32 page_size_mask;
+};
+#define VFIO_IOMMU_SPAPR_TCE_QUERY _IO(VFIO_TYPE, VFIO_BASE + 17)
+
+struct vfio_iommu_spapr_tce_create {
+ __u32 argsz;
+ /* in */
+ __u32 page_shift;
+ __u32 window_shift;
+ /* out */
+ __u64 start_addr;
+
+};
+#define VFIO_IOMMU_SPAPR_TCE_CREATE _IO(VFIO_TYPE, VFIO_BASE + 18)
+
+struct vfio_iommu_spapr_tce_remove {
+ __u32 argsz;
+ /* in */
+ __u64 start_addr;
+};
+#define VFIO_IOMMU_SPAPR_TCE_REMOVE _IO(VFIO_TYPE, VFIO_BASE + 19)
+
+struct vfio_iommu_spapr_tce_reset {
+ __u32 argsz;
+};
+#define VFIO_IOMMU_SPAPR_TCE_RESET _IO(VFIO_TYPE, VFIO_BASE + 20)
+
/* ***************************************************************** */
#endif /* _UAPIVFIO_H */
--
2.0.0
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