Commit 4a4f1073 authored by Bob Pearson's avatar Bob Pearson Committed by Jason Gunthorpe
Browse files

RDMA/rxe: Collect mca init code in a subroutine 

Collect initialization code for struct rxe_mca into a subroutine,
__rxe_init_mca(), to cleanup rxe_attach_mcg() in rxe_mcast.c. Check
limit on total number of attached qp's.

Link: https://lore.kernel.org/r/20220223230706.50332-3-rpearsonhpe@gmail.com


Signed-off-by: default avatarBob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 6a8a2e47

drivers/infiniband/sw/rxe/rxe_mcast.c

+43 −15
Original line number Diff line number Diff line
@@ -259,6 +259,46 @@ static void rxe_destroy_mcg(struct rxe_mcg *mcg) 
	spin_unlock_irqrestore(&mcg->rxe->mcg_lock, flags);

}



/**

 * __rxe_init_mca - initialize a new mca holding lock

 * @qp: qp object

 * @mcg: mcg object

 * @mca: empty space for new mca

 *

 * Context: caller must hold references on qp and mcg, rxe->mcg_lock

 * and pass memory for new mca

 *

 * Returns: 0 on success else an error

 */

static int __rxe_init_mca(struct rxe_qp *qp, struct rxe_mcg *mcg,

			  struct rxe_mca *mca)

{

	struct rxe_dev *rxe = to_rdev(qp->ibqp.device);

	int n;



	n = atomic_inc_return(&rxe->mcg_attach);

	if (n > rxe->attr.max_total_mcast_qp_attach) {

		atomic_dec(&rxe->mcg_attach);

		return -ENOMEM;

	}



	n = atomic_inc_return(&mcg->qp_num);

	if (n > rxe->attr.max_mcast_qp_attach) {

		atomic_dec(&mcg->qp_num);

		atomic_dec(&rxe->mcg_attach);

		return -ENOMEM;

	}



	atomic_inc(&qp->mcg_num);



	rxe_add_ref(qp);

	mca->qp = qp;



	list_add_tail(&mca->qp_list, &mcg->qp_list);



	return 0;

}



static int rxe_attach_mcg(struct rxe_dev *rxe, struct rxe_qp *qp,

				  struct rxe_mcg *mcg)

{
@@ -291,22 +331,9 @@ static int rxe_attach_mcg(struct rxe_dev *rxe, struct rxe_qp *qp, 
		}

	}



	/* check limits after checking if already attached */

	if (atomic_inc_return(&mcg->qp_num) > rxe->attr.max_mcast_qp_attach) {

		atomic_dec(&mcg->qp_num);

	err = __rxe_init_mca(qp, mcg, mca);

	if (err)

		kfree(mca);

		err = -ENOMEM;

		goto out;

	}



	/* protect pointer to qp in mca */

	rxe_add_ref(qp);

	mca->qp = qp;



	atomic_inc(&qp->mcg_num);

	list_add(&mca->qp_list, &mcg->qp_list);



	err = 0;

out:

	spin_unlock_irqrestore(&rxe->mcg_lock, flags);

	return err;
@@ -329,6 +356,7 @@ static int rxe_detach_mcg(struct rxe_dev *rxe, struct rxe_qp *qp, 
		if (mca->qp == qp) {

			list_del(&mca->qp_list);

			atomic_dec(&qp->mcg_num);

			atomic_dec(&rxe->mcg_attach);

			rxe_drop_ref(qp);



			/* if the number of qp's attached to the

drivers/infiniband/sw/rxe/rxe_verbs.h

+1 −0
Original line number Diff line number Diff line
@@ -401,6 +401,7 @@ struct rxe_dev { 
	spinlock_t		mcg_lock;

	struct rb_root		mcg_tree;

	atomic_t		mcg_num;

	atomic_t		mcg_attach;



	spinlock_t		pending_lock; /* guard pending_mmaps */

	struct list_head	pending_mmaps;