Date: Mon, 7 May 2012 13:38:12 -0400 From: John Baldwin <jhb@freebsd.org> To: Andriy Gapon <avg@freebsd.org> Cc: freebsd-fs@freebsd.org, freebsd-hackers@freebsd.org, Bruce Evans <brde@optusnet.com.au> Subject: Re: [review request] zfsboot/zfsloader: support accessing filesystems within a pool Message-ID: <201205071338.12807.jhb@freebsd.org> In-Reply-To: <4FA7E729.4000308@FreeBSD.org> References: <4F8999D2.1080902@FreeBSD.org> <4FA7E069.8020208@FreeBSD.org> <4FA7E729.4000308@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Monday, May 07, 2012 11:15:53 am Andriy Gapon wrote: > on 07/05/2012 17:47 Andriy Gapon said the following: > > on 07/05/2012 16:53 John Baldwin said the following: > >> Ok. Maybe add one comment to the bootargs.h head to explain that the 'bootargs' > >> struct starts at ARGOFF and can grow up, while struct bootinfo is copied such that > >> it's end is at the top of the argument area and grows down. > > > > Will do. > > Could you please check the wording and correct it or suggest alternatives? > Thank you. > > diff --git a/sys/boot/i386/common/bootargs.h b/sys/boot/i386/common/bootargs.h > index 510efdd..8bc1b32 100644 > --- a/sys/boot/i386/common/bootargs.h > +++ b/sys/boot/i386/common/bootargs.h > @@ -29,6 +29,15 @@ > #define BF_OFF 8 /* offsetof(struct bootargs, bootflags) */ > #define BI_OFF 20 /* offsetof(struct bootargs, bootinfo) */ > > +/* > + * We reserve some space above BTX allocated stack for the arguments > + * and certain data that could hang off them. Currently only struct bootinfo > + * is supported in that category. The bootinfo is placed at the top > + * of the arguments area and the actual arguments are placed at ARGOFF offset > + * from the top and grow towards the top. Hopefully we have enough space > + * for bootinfo and the arguments to not run into each other. > + * Arguments area below ARGOFF is reserved for future use. > + */ > #define ARGSPACE 0x1000 /* total size of the BTX args area */ > #define ARGOFF 0x800 /* actual args offset within the args area */ > #define ARGADJ (ARGSPACE - ARGOFF) I think this is good, thanks! -- John Baldwin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201205071338.12807.jhb>