Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6c8e6bb2 authored by Sukadev Bhattiprolu's avatar Sukadev Bhattiprolu Committed by Michael Ellerman
Browse files

powerpc/vas: Add support for user receive window 



Add support for user space receive window (for the Fast thread-wakeup
coprocessor type)

Signed-off-by: default avatarSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 61f3cca8

arch/powerpc/platforms/powernv/vas-window.c

+49 −7
Original line number Diff line number Diff line
@@ -16,7 +16,8 @@ 
#include <linux/log2.h>

#include <linux/rcupdate.h>

#include <linux/cred.h>



#include <asm/switch_to.h>

#include <asm/ppc-opcode.h>

#include "vas.h"

#include "copy-paste.h"
@@ -597,6 +598,32 @@ static void put_rx_win(struct vas_window *rxwin) 
	atomic_dec(&rxwin->num_txwins);

}



/*

 * Find the user space receive window given the @pswid.

 *      - We must have a valid vasid and it must belong to this instance.

 *        (so both send and receive windows are on the same VAS instance)

 *      - The window must refer to an OPEN, FTW, RECEIVE window.

 *

 * NOTE: We access ->windows[] table and assume that vinst->mutex is held.

 */

static struct vas_window *get_user_rxwin(struct vas_instance *vinst, u32 pswid)

{

	int vasid, winid;

	struct vas_window *rxwin;



	decode_pswid(pswid, &vasid, &winid);



	if (vinst->vas_id != vasid)

		return ERR_PTR(-EINVAL);



	rxwin = vinst->windows[winid];



	if (!rxwin || rxwin->tx_win || rxwin->cop != VAS_COP_TYPE_FTW)

		return ERR_PTR(-EINVAL);



	return rxwin;

}



/*

 * Get the VAS receive window associated with NX engine identified

 * by @cop and if applicable, @pswid.
@@ -610,10 +637,10 @@ static struct vas_window *get_vinst_rxwin(struct vas_instance *vinst, 


	mutex_lock(&vinst->mutex);



	if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI)

		rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL);

	if (cop == VAS_COP_TYPE_FTW)

		rxwin = get_user_rxwin(vinst, pswid);

	else

		rxwin = ERR_PTR(-EINVAL);

		rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL);



	if (!IS_ERR(rxwin))

		atomic_inc(&rxwin->num_txwins);
@@ -937,10 +964,9 @@ static void init_winctx_for_txwin(struct vas_window *txwin, 
	winctx->tx_word_mode = txattr->tx_win_ord_mode;

	winctx->rsvd_txbuf_count = txattr->rsvd_txbuf_count;



	if (winctx->nx_win) {

		winctx->data_stamp = true;

	winctx->intr_disable = true;

	}

	if (winctx->nx_win)

		winctx->data_stamp = true;



	winctx->lpid = txattr->lpid;

	winctx->pidr = txattr->pidr;
@@ -985,6 +1011,14 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop, 
	if (!tx_win_args_valid(cop, attr))

		return ERR_PTR(-EINVAL);



	/*

	 * If caller did not specify a vasid but specified the PSWID of a

	 * receive window (applicable only to FTW windows), use the vasid

	 * from that receive window.

	 */

	if (vasid == -1 && attr->pswid)

		decode_pswid(attr->pswid, &vasid, NULL);



	vinst = find_vas_instance(vasid);

	if (!vinst) {

		pr_devel("vasid %d not found!\n", vasid);
@@ -1031,6 +1065,14 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop, 
		}

	}



	/*

	 * Now that we have a send window, ensure context switch issues

	 * CP_ABORT for this thread.

	 */

	rc = -EINVAL;

	if (set_thread_uses_vas() < 0)

		goto free_window;



	set_vinst_win(vinst, txwin);



	return txwin;