Merge tag 'rds-odp-for-5.5' into rdma.git for-next

From https://git.kernel.org/pub/scm/linux/kernel/git/leon/linux-rdma

Leon Romanovsky says:

====================
Use ODP MRs for kernel ULPs

The following series extends MR creation routines to allow creation of
user MRs through kernel ULPs as a proxy. The immediate use case is to
allow RDS to work over FS-DAX, which requires ODP (on-demand-paging)
MRs to be created and such MRs were not possible to create prior this
series.

The first part of this patchset extends RDMA to have special verb
ib_reg_user_mr(). The common use case that uses this function is a
userspace application that allocates memory for HCA access but the
responsibility to register the memory at the HCA is on an kernel ULP.
This ULP acts as an agent for the userspace application.

The second part provides advise MR functionality for ULPs. This is
integral part of ODP flows and used to trigger pagefaults in advance
to prepare memory before running working set.

The third part is actual user of those in-kernel APIs.
====================

* tag 'rds-odp-for-5.5':
  net/rds: Use prefetch for On-Demand-Paging MR
  net/rds: Handle ODP mr registration/unregistration
  net/rds: Detect need of On-Demand-Paging memory registration
  RDMA/mlx5: Fix handling of IOVA != user_va in ODP paths
  IB/mlx5: Mask out unsupported ODP capabilities for kernel QPs
  RDMA/mlx5: Don't fake udata for kernel path
  IB/mlx5: Add ODP WQE handlers for kernel QPs
  IB/core: Add interface to advise_mr for kernel users
  IB/core: Introduce ib_reg_user_mr
  IB: Allow calls to ib_umem_get from kernel ULPs

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 7 insertions, 22 deletions

diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
index b9baf7d0a5cb..cb3b17a7b9b0 100644
--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -110,15 +110,12 @@ out_page_list:
  * They exist only to hold the per_mm reference to help the driver create
  * children umems.
  *
- * @udata: udata from the syscall being used to create the umem
+ * @device: IB device to create UMEM
  * @access: ib_reg_mr access flags
  */
-struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_udata *udata,
+struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_device *device,
 					       int access)
 {
-	struct ib_ucontext *context =
-		container_of(udata, struct uverbs_attr_bundle, driver_udata)
-			->context;
 	struct ib_umem *umem;
 	struct ib_umem_odp *umem_odp;
 	int ret;
@@ -126,14 +123,11 @@ struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_udata *udata,
 	if (access & IB_ACCESS_HUGETLB)
 		return ERR_PTR(-EINVAL);
 
-	if (!context)
-		return ERR_PTR(-EIO);
-
 	umem_odp = kzalloc(sizeof(*umem_odp), GFP_KERNEL);
 	if (!umem_odp)
 		return ERR_PTR(-ENOMEM);
 	umem = &umem_odp->umem;
-	umem->ibdev = context->device;
+	umem->ibdev = device;
 	umem->writable = ib_access_writable(access);
 	umem->owning_mm = current->mm;
 	umem_odp->is_implicit_odp = 1;
@@ -201,7 +195,7 @@ EXPORT_SYMBOL(ib_umem_odp_alloc_child);
 /**
  * ib_umem_odp_get - Create a umem_odp for a userspace va
  *
- * @udata: userspace context to pin memory for
+ * @device: IB device struct to get UMEM
  * @addr: userspace virtual address to start at
  * @size: length of region to pin
  * @access: IB_ACCESS_xxx flags for memory being pinned
@@ -210,23 +204,14 @@ EXPORT_SYMBOL(ib_umem_odp_alloc_child);
  * pinning, instead, stores the mm for future page fault handling in
  * conjunction with MMU notifiers.
  */
-struct ib_umem_odp *ib_umem_odp_get(struct ib_udata *udata, unsigned long addr,
-				    size_t size, int access,
+struct ib_umem_odp *ib_umem_odp_get(struct ib_device *device,
+				    unsigned long addr, size_t size, int access,
 				    const struct mmu_interval_notifier_ops *ops)
 {
 	struct ib_umem_odp *umem_odp;
-	struct ib_ucontext *context;
 	struct mm_struct *mm;
 	int ret;
 
-	if (!udata)
-		return ERR_PTR(-EIO);
-
-	context = container_of(udata, struct uverbs_attr_bundle, driver_udata)
-			  ->context;
-	if (!context)
-		return ERR_PTR(-EIO);
-
 	if (WARN_ON_ONCE(!(access & IB_ACCESS_ON_DEMAND)))
 		return ERR_PTR(-EINVAL);
 
@@ -234,7 +219,7 @@ struct ib_umem_odp *ib_umem_odp_get(struct ib_udata *udata, unsigned long addr,
 	if (!umem_odp)
 		return ERR_PTR(-ENOMEM);
 
-	umem_odp->umem.ibdev = context->device;
+	umem_odp->umem.ibdev = device;
 	umem_odp->umem.length = size;
 	umem_odp->umem.address = addr;
 	umem_odp->umem.writable = ib_access_writable(access);