Date: Sat, 15 Mar 2014 11:18:07 +0330 From: Hooman Fazaeli <hoomanfazaeli@gmail.com> To: Rui Paulo <rpaulo@FreeBSD.org> Cc: FreeBSD Hackers <freebsd-hackers@freebsd.org> Subject: Re: mbuf question Message-ID: <532405B7.2020007@gmail.com> In-Reply-To: <BBAFAB2A-F496-46A2-8FE0-224BE562EAA7@FreeBSD.org> References: <53230214.7010501@gmail.com> <BBAFAB2A-F496-46A2-8FE0-224BE562EAA7@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On 3/15/2014 5:09 AM, Rui Paulo wrote: > On 14 Mar 2014, at 06:20, Hooman Fazaeli <hoomanfazaeli@gmail.com> wrote: > >> Hi list, >> >> Is it safe to use m->m_pktdat area to store some arbitrary data about packets allocated as mbuf+cluster pair? > No, because m_pktdat is really MH_databuf which is part of a union with MH_ext which is set when you allocate an mbuf cluster. > > -- > Rui Paulo > > > Thanks for the point. I simply overlooked the fact that MH_dat is a union, not a struct. What about the area started at (m->m_ext + 1) whose size is (MHLEN - sizeof(struct m_ext))? Is there any known uses of this area in the stack? -- Best regards. Hooman Fazaeli
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?532405B7.2020007>