[src/trunk]: src/sys/dev/pci Make descriptor_num in ixl(4) readonly

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

details:   https://anonhg.NetBSD.org/src/rev/3712ffae107e
branches:  trunk
changeset: 1013025:3712ffae107e
user:      yamaguchi <yamaguchi%NetBSD.org@localhost>
date:      Wed Aug 19 09:22:05 2020 +0000

description:
Make descriptor_num in ixl(4) readonly
because ixl(4) does not support reallocating related resources

pointed out by knakahara@, thanks.

diffstat:

 sys/dev/pci/if_ixl.c |  54 +++++----------------------------------------------
 1 files changed, 6 insertions(+), 48 deletions(-)

diffs (98 lines):

diff -r 1ce5369deba6 -r 3712ffae107e sys/dev/pci/if_ixl.c
--- a/sys/dev/pci/if_ixl.c      Wed Aug 19 09:07:57 2020 +0000
+++ b/sys/dev/pci/if_ixl.c      Wed Aug 19 09:22:05 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_ixl.c,v 1.73 2020/08/19 09:07:57 yamaguchi Exp $    */
+/*     $NetBSD: if_ixl.c,v 1.74 2020/08/19 09:22:05 yamaguchi Exp $    */
 
 /*
  * Copyright (c) 2013-2015, Intel Corporation
@@ -74,7 +74,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_ixl.c,v 1.73 2020/08/19 09:07:57 yamaguchi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_ixl.c,v 1.74 2020/08/19 09:22:05 yamaguchi Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_net_mpsafe.h"
@@ -907,7 +907,6 @@
 static int     ixl_setup_sysctls(struct ixl_softc *);
 static void    ixl_teardown_sysctls(struct ixl_softc *);
 static int     ixl_sysctl_itr_handler(SYSCTLFN_PROTO);
-static int     ixl_sysctl_ndescs_handler(SYSCTLFN_PROTO);
 static int     ixl_queue_pairs_alloc(struct ixl_softc *);
 static void    ixl_queue_pairs_free(struct ixl_softc *);
 
@@ -6656,10 +6655,9 @@
                goto out;
 
        error = sysctl_createv(log, 0, &rxnode, NULL,
-           CTLFLAG_READWRITE, CTLTYPE_INT, "descriptor_num",
+           CTLFLAG_READONLY, CTLTYPE_INT, "descriptor_num",
            SYSCTL_DESCR("the number of rx descriptors"),
-           ixl_sysctl_ndescs_handler, 0,
-           (void *)sc, 0, CTL_CREATE, CTL_EOL);
+           NULL, 0, &sc->sc_rx_ring_ndescs, 0, CTL_CREATE, CTL_EOL);
        if (error)
                goto out;
 
@@ -6695,10 +6693,9 @@
                goto out;
 
        error = sysctl_createv(log, 0, &txnode, NULL,
-           CTLFLAG_READWRITE, CTLTYPE_INT, "descriptor_num",
+           CTLFLAG_READONLY, CTLTYPE_INT, "descriptor_num",
            SYSCTL_DESCR("the number of tx descriptors"),
-           ixl_sysctl_ndescs_handler, 0,
-           (void *)sc, 0, CTL_CREATE, CTL_EOL);
+           NULL, 0, &sc->sc_tx_ring_ndescs, 0, CTL_CREATE, CTL_EOL);
        if (error)
                goto out;
 
@@ -6781,45 +6778,6 @@
        return 0;
 }
 
-static int
-ixl_sysctl_ndescs_handler(SYSCTLFN_ARGS)
-{
-       struct sysctlnode node = *rnode;
-       struct ixl_softc *sc = (struct ixl_softc *)node.sysctl_data;
-       struct ifnet *ifp = &sc->sc_ec.ec_if;
-       unsigned int *ndescs_ptr, ndescs, n;
-       int error;
-
-       if (ixl_sysctlnode_is_rx(&node)) {
-               ndescs_ptr = &sc->sc_rx_ring_ndescs;
-       } else {
-               ndescs_ptr = &sc->sc_tx_ring_ndescs;
-       }
-
-       ndescs = *ndescs_ptr;
-       node.sysctl_data = &ndescs;
-       node.sysctl_size = sizeof(ndescs);
-
-       error = sysctl_lookup(SYSCTLFN_CALL(&node));
-
-       if (error || newp == NULL)
-               return error;
-
-       if (ISSET(ifp->if_flags, IFF_RUNNING))
-               return EBUSY;
-
-       if (ndescs < 8 || 0xffff < ndescs)
-               return EINVAL;
-
-       n = 1U << (fls32(ndescs) - 1);
-       if (n != ndescs)
-               return EINVAL;
-
-       *ndescs_ptr = ndescs;
-
-       return 0;
-}
-
 static struct workqueue *
 ixl_workq_create(const char *name, pri_t prio, int ipl, int flags)
 {