Date: Mon, 1 Oct 2001 13:04:55 -0700 (PDT) From: Matthew Jacob <mjacob@feral.com> To: freebsd-net@freebsd.org Subject: review of minor clarifying comments Message-ID: <Pine.BSF.4.21.0110011302130.99893-100000@beppo>
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This bit me in the butt yet again about FreeBSD and some assumptions about how a NIC's softc is laid out- I don't really it stated elsewhere, so a couple source file comments seem in order.. Frankly, this kind of assumption is dangerous and unnecessary with methods, but at the very least it ought to be commented, no? -matt Index: net/if_var.h =================================================================== RCS file: /home/ncvs/src/sys/net/if_var.h,v retrieving revision 1.37 diff -u -r1.37 if_var.h --- net/if_var.h 2001/09/18 17:41:42 1.37 +++ net/if_var.h 2001/10/01 20:00:08 @@ -105,6 +105,11 @@ * * (Would like to call this struct ``if'', but C isn't PL/1.) */ + +/* + * NB: For FreeBSD, it is assumed that each NIC driver's softc starts with + * one of these structures, typically held within an arpcom structure. + */ struct ifnet { void *if_softc; /* pointer to driver state */ char *if_name; /* name, e.g. ``en'' or ``lo'' */ Index: dev/mii/mii.c =================================================================== RCS file: /home/ncvs/src/sys/dev/mii/mii.c,v retrieving revision 1.9 diff -u -r1.9 mii.c --- dev/mii/mii.c 2001/09/29 18:40:06 1.9 +++ dev/mii/mii.c 2001/10/01 20:00:09 @@ -167,6 +167,9 @@ struct mii_data *mii; mii = device_get_softc(dev); + /* + * Note that each NIC's softc must start with an ifnet structure. + */ mii->mii_ifp = device_get_softc(device_get_parent(dev)); v = device_get_ivars(dev); ifmedia_upd = v[0]; @@ -233,6 +236,9 @@ MIIBUS_LINKCHG(parent); mii = device_get_softc(dev); + /* + * Note that each NIC's softc must start with an ifnet structure. + */ ifp = device_get_softc(parent); if (mii->mii_media_status & IFM_AVALID) { To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message
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