From 6c8e6bb2a52d5e7ae5bbde21c21f6d5dfd6e9ae8 Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Tue, 7 Nov 2017 18:23:58 -0800 Subject: [PATCH] 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: Sukadev Bhattiprolu Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/powernv/vas-window.c | 56 ++++++++++++++++++--- 1 file changed, 49 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c index 82754924c2bc..2b3eb01ab110 100644 --- a/arch/powerpc/platforms/powernv/vas-window.c +++ b/arch/powerpc/platforms/powernv/vas-window.c @@ -16,7 +16,8 @@ #include #include #include - +#include +#include #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->intr_disable = true; + if (winctx->nx_win) winctx->data_stamp = true; - winctx->intr_disable = 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; -- 2.30.2