add mmap maple tree for vfio_device_file, this allows vfio devices to
create per mmap request options. the vfio device needs to
insert/allocate the region range offset & size and make it accessible
for the user, probably when the user is calling
DEVICE_GET_REGION_INFO, and then vfio uses the maple_tree to find the
entry (vfio_mmap) needed for mmap op, this adds the vfio_mmap_init &
vfio_mmap_free for initialization and freeing the entry, the freeing
is done through the free callback in the vfio_mmap_ops, which
vfio_devices should implement if they are allocating an entry.
Signed-off-by: Mahmoud Adam <mngyadam@xxxxxxxxx>
---
I didn't find a situation where we would need to use ref counting for
now, so I didn't implement it, I think most cases are already handled
by file ref counting, but maybe I'm overlooking something here.
drivers/vfio/vfio.h | 1 +
drivers/vfio/vfio_main.c | 29 +++++++++++++++++++++++++++++
include/linux/vfio.h | 17 +++++++++++++++++
3 files changed, 47 insertions(+)
diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
index 50128da18bcaf..3f0cf2dd41116 100644
--- a/drivers/vfio/vfio.h
+++ b/drivers/vfio/vfio.h
@@ -19,6 +19,7 @@ struct vfio_container;
struct vfio_device_file {
struct vfio_device *device;
struct vfio_group *group;
+ struct maple_tree mmap_mt;
u8 access_granted;
u32 devid; /* only valid when iommufd is valid */
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 1fd261efc582d..4c4af4de60d12 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -39,6 +39,7 @@
#include <linux/interval_tree.h>
#include <linux/iova_bitmap.h>
#include <linux/iommufd.h>
+#include <linux/maple_tree.h>
#include "vfio.h"
#define DRIVER_VERSION "0.3"
@@ -498,6 +499,7 @@ vfio_allocate_device_file(struct vfio_device *device)
df->device = device;
spin_lock_init(&df->kvm_ref_lock);
+ mt_init_flags(&df->mmap_mt, MT_FLAGS_ALLOC_RANGE);
return df;
}
@@ -622,6 +624,25 @@ static inline void vfio_device_pm_runtime_put(struct vfio_device *device)
pm_runtime_put(dev);
}
+void vfio_mmap_init(struct vfio_device *vdev, struct vfio_mmap *vmmap,
+ u32 region_flags, u64 offset, u64 size,
+ struct vfio_mmap_ops *ops)
+{
+ vmmap->owner = vdev;
+ vmmap->offset = offset;
+ vmmap->ops = ops;
+ vmmap->size = size;
+ vmmap->region_flags = region_flags;
+}
+EXPORT_SYMBOL_GPL(vfio_mmap_init);
+
+void vfio_mmap_free(struct vfio_mmap *vmmap)
+{
+ if (vmmap->ops && vmmap->ops->free)
+ vmmap->ops->free(vmmap);
+}
+EXPORT_SYMBOL_GPL(vfio_mmap_free);
+
/*
* VFIO Device fd
*/
@@ -629,14 +650,22 @@ static int vfio_device_fops_release(struct inode *inode, struct file *filep)
{
struct vfio_device_file *df = filep->private_data;
struct vfio_device *device = df->device;
+ struct vfio_mmap *vmmap;
+ unsigned long index = 0;
if (df->group)
vfio_df_group_close(df);
else
vfio_df_unbind_iommufd(df);
+ mt_for_each(&df->mmap_mt, vmmap, index, ULONG_MAX) {
+ mtree_erase(&df->mmap_mt, index);
+ vfio_mmap_free(vmmap);
+ }
+
vfio_device_put_registration(device);
+ mtree_destroy(&df->mmap_mt);
kfree(df);
return 0;
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 707b00772ce1f..6e0aca05aa406 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -80,6 +80,19 @@ struct vfio_device {
#endif
};
+struct vfio_mmap {
+ struct vfio_device *owner;
+ u64 offset;
+ u64 size;
+ u32 region_flags;
+ struct vfio_mmap_ops *ops;
+};
+
+struct vfio_mmap_ops {
+ void (*free)(struct vfio_mmap *vmmap);
+};
+
+
/**
* struct vfio_device_ops - VFIO bus driver device callbacks
*
@@ -338,6 +351,10 @@ int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova,
void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage);
int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova,
void *data, size_t len, bool write);
+void vfio_mmap_init(struct vfio_device *vdev, struct vfio_mmap *vmmap,
+ u32 region_flags, u64 offset, u64 size,
+ struct vfio_mmap_ops *ops);
+void vfio_mmap_free(struct vfio_mmap *vmmap);
/*
* Sub-module helpers
--
2.47.3
Amazon Web Services Development Center Germany GmbH
Tamara-Danz-Str. 13
10243 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B
Sitz: Berlin
Ust-ID: DE 365 538 597
