[src/trunk]: src/sys/dev/pci msk(4): Avoid bus_dmamap_destroy() in msk_stop()

[jakllsch <jakllsch%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/8d613e347964
branches:  trunk
changeset: 971222:8d613e347964
user:      jakllsch <jakllsch%NetBSD.org@localhost>
date:      Sat Apr 18 17:31:52 2020 +0000

description:
msk(4): Avoid bus_dmamap_destroy() in msk_stop()

bus_dmamap_destroy() can not be executed in soft interrupt context,
and msk_stop() can be called in soft interrupt context.

As such, move creation and destruction of tx dmamaps to attach() and
detach() functions.

diffstat:

 sys/dev/pci/if_msk.c |  58 ++++++++++++++++++++++++++-------------------------
 1 files changed, 30 insertions(+), 28 deletions(-)

diffs (135 lines):

diff -r 145fdb8bb479 -r 8d613e347964 sys/dev/pci/if_msk.c
--- a/sys/dev/pci/if_msk.c      Sat Apr 18 17:22:26 2020 +0000
+++ b/sys/dev/pci/if_msk.c      Sat Apr 18 17:31:52 2020 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: if_msk.c,v 1.98 2020/02/04 05:44:14 thorpej Exp $ */
+/* $NetBSD: if_msk.c,v 1.99 2020/04/18 17:31:52 jakllsch Exp $ */
 /*     $OpenBSD: if_msk.c,v 1.79 2009/10/15 17:54:56 deraadt Exp $     */
 
 /*
@@ -52,7 +52,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_msk.c,v 1.98 2020/02/04 05:44:14 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_msk.c,v 1.99 2020/04/18 17:31:52 jakllsch Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -456,17 +456,13 @@
 static int
 msk_init_tx_ring(struct sk_if_softc *sc_if)
 {
-       struct sk_softc         *sc = sc_if->sk_softc;
        struct msk_chain_data   *cd = &sc_if->sk_cdata;
        struct msk_ring_data    *rd = sc_if->sk_rdata;
        struct msk_tx_desc      *t;
-       bus_dmamap_t            dmamap;
-       struct sk_txmap_entry   *entry;
        int                     i, nexti;
 
        memset(rd->sk_tx_ring, 0, sizeof(struct msk_tx_desc) * MSK_TX_RING_CNT);
 
-       SIMPLEQ_INIT(&sc_if->sk_txmap_head);
        for (i = 0; i < MSK_TX_RING_CNT; i++) {
                cd->sk_tx_chain[i].sk_le = &rd->sk_tx_ring[i];
                if (i == (MSK_TX_RING_CNT - 1))
@@ -474,18 +470,6 @@
                else
                        nexti = i + 1;
                cd->sk_tx_chain[i].sk_next = &cd->sk_tx_chain[nexti];
-
-               if (bus_dmamap_create(sc->sc_dmatag, SK_JLEN, SK_NTXSEG,
-                  SK_JLEN, 0, BUS_DMA_NOWAIT, &dmamap))
-                       return ENOBUFS;
-
-               entry = malloc(sizeof(*entry), M_DEVBUF, M_NOWAIT);
-               if (!entry) {
-                       bus_dmamap_destroy(sc->sc_dmatag, dmamap);
-                       return ENOBUFS;
-               }
-               entry->dmamap = dmamap;
-               SIMPLEQ_INSERT_HEAD(&sc_if->sk_txmap_head, entry, link);
        }
 
        sc_if->sk_cdata.sk_tx_prod = 0;
@@ -1135,6 +1119,8 @@
        struct sk_if_softc *sc_if = device_private(self);
        struct sk_softc *sc = device_private(parent);
        struct skc_attach_args *sa = aux;
+       bus_dmamap_t dmamap;
+       struct sk_txmap_entry *entry;
        struct ifnet *ifp;
        struct mii_data * const mii = &sc_if->sk_mii;
        void *kva;
@@ -1211,6 +1197,23 @@
                aprint_error(": can't load dma map\n");
                goto fail_3;
        }
+
+       SIMPLEQ_INIT(&sc_if->sk_txmap_head);
+       for (i = 0; i < MSK_TX_RING_CNT; i++) {
+               sc_if->sk_cdata.sk_tx_chain[i].sk_mbuf = NULL;
+
+               if (bus_dmamap_create(sc->sc_dmatag, SK_JLEN, SK_NTXSEG,
+                   SK_JLEN, 0, BUS_DMA_NOWAIT, &dmamap)) {
+                       aprint_error_dev(sc_if->sk_dev,
+                           "Can't create TX dmamap\n");
+                       goto fail_3;
+               }
+
+               entry = malloc(sizeof(*entry), M_DEVBUF, M_WAITOK);
+               entry->dmamap = dmamap;
+               SIMPLEQ_INSERT_HEAD(&sc_if->sk_txmap_head, entry, link);
+       }
+
        sc_if->sk_rdata = (struct msk_ring_data *)kva;
        memset(sc_if->sk_rdata, 0, sizeof(struct msk_ring_data));
 
@@ -1312,6 +1315,7 @@
 {
        struct sk_if_softc *sc_if = device_private(self);
        struct sk_softc *sc = sc_if->sk_softc;
+       struct sk_txmap_entry *entry;
        struct ifnet *ifp = &sc_if->sk_ethercom.ec_if;
 
        if (sc->sk_if[sc_if->sk_port] == NULL)
@@ -1319,6 +1323,12 @@
 
        msk_stop(ifp, 1);
 
+       while ((entry = SIMPLEQ_FIRST(&sc_if->sk_txmap_head))) {
+               SIMPLEQ_REMOVE_HEAD(&sc_if->sk_txmap_head, link);
+               bus_dmamap_destroy(sc->sc_dmatag, entry->dmamap);
+               free(entry, M_DEVBUF);
+       }
+
        if (--sc->rnd_attached == 0)
                rnd_detach_source(&sc->rnd_source);
 
@@ -2679,23 +2689,15 @@
                            dma->dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
 
                        bus_dmamap_unload(sc->sc_dmatag, dma->dmamap);
-#if 1
+
                        SIMPLEQ_INSERT_HEAD(&sc_if->sk_txmap_head,
                            sc_if->sk_cdata.sk_tx_map[i], link);
                        sc_if->sk_cdata.sk_tx_map[i] = 0;
-#endif
+
                        m_freem(sc_if->sk_cdata.sk_tx_chain[i].sk_mbuf);
                        sc_if->sk_cdata.sk_tx_chain[i].sk_mbuf = NULL;
                }
        }
-
-#if 1
-       while ((dma = SIMPLEQ_FIRST(&sc_if->sk_txmap_head))) {
-               SIMPLEQ_REMOVE_HEAD(&sc_if->sk_txmap_head, link);
-               bus_dmamap_destroy(sc->sc_dmatag, dma->dmamap);
-               free(dma, M_DEVBUF);
-       }
-#endif
 }
 
 CFATTACH_DECL3_NEW(mskc, sizeof(struct sk_softc), mskc_probe, mskc_attach,