diff mbox series

[v4,03/11] iommufd: Add iommufd_verify_unfinalized_object

Message ID b48254df9ee530bedaf436e5aff279d9a882a7ca.1729553811.git.nicolinc@nvidia.com
State Superseded
Headers show
Series iommufd: Add vIOMMU infrastructure (Part-1) | expand

Commit Message

Nicolin Chen Oct. 22, 2024, 12:19 a.m. UTC 
To support driver-allocated vIOMMU objects, it's suggested to call the
allocator helper in IOMMU dirvers. However, there is no guarantee that
drivers will all use it and allocate objects properly.

Add a helper for iommufd core to verify if an unfinalized object is at
least reserved in the ictx.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
 drivers/iommu/iommufd/iommufd_private.h |  3 +++
 drivers/iommu/iommufd/main.c            | 20 ++++++++++++++++++++
 2 files changed, 23 insertions(+)

Comments

Tian, Kevin Oct. 25, 2024, 8:49 a.m. UTC | #1 
> From: Nicolin Chen <nicolinc@nvidia.com>
> Sent: Tuesday, October 22, 2024 8:19 AM
> 
> To support driver-allocated vIOMMU objects, it's suggested to call the
> allocator helper in IOMMU dirvers. However, there is no guarantee that
> drivers will all use it and allocate objects properly.
> 
> Add a helper for iommufd core to verify if an unfinalized object is at
> least reserved in the ictx.
> 
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
diff mbox series

Patch

diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 5bd41257f2ef..d53c1ca75532 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -152,6 +152,9 @@  static inline void iommufd_put_object(struct iommufd_ctx *ictx,
 		wake_up_interruptible_all(&ictx->destroy_wait);
 }
 
+int iommufd_verify_unfinalized_object(struct iommufd_ctx *ictx,
+				      struct iommufd_object *to_verify);
+
 void iommufd_object_abort(struct iommufd_ctx *ictx, struct iommufd_object *obj);
 void iommufd_object_abort_and_destroy(struct iommufd_ctx *ictx,
 				      struct iommufd_object *obj);
diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c
index 92bd075108e5..e244fed1b7ab 100644
--- a/drivers/iommu/iommufd/main.c
+++ b/drivers/iommu/iommufd/main.c
@@ -89,6 +89,26 @@  struct iommufd_object *iommufd_get_object(struct iommufd_ctx *ictx, u32 id,
 	return obj;
 }
 
+int iommufd_verify_unfinalized_object(struct iommufd_ctx *ictx,
+				      struct iommufd_object *to_verify)
+{
+	XA_STATE(xas, &ictx->objects, 0);
+	struct iommufd_object *obj;
+	int rc = 0;
+
+	if (!to_verify || !to_verify->id)
+		return -EINVAL;
+	xas.xa_index = to_verify->id;
+
+	xa_lock(&ictx->objects);
+	obj = xas_load(&xas);
+	/* Being an unfinalized object, the loaded obj is a reserved space */
+	if (obj != XA_ZERO_ENTRY)
+		rc = -ENOENT;
+	xa_unlock(&ictx->objects);
+	return rc;
+}
+
 static int iommufd_object_dec_wait_shortterm(struct iommufd_ctx *ictx,
 					     struct iommufd_object *to_destroy)
 {