Date: Sun, 17 Jan 2016 10:08:53 +0200 From: Konstantin Belousov <kostikbel@gmail.com> To: Bruce Evans <brde@optusnet.com.au> Cc: Rick Macklem <rmacklem@uoguelph.ca>, FreeBSD Filesystems <freebsd-fs@freebsd.org>, Kirk McKusick <mckusick@mckusick.com> Subject: Re: panic ffs_truncate3 (maybe fuse being evil) Message-ID: <20160117080853.GP3942@kib.kiev.ua> In-Reply-To: <20160117172549.C11309@besplex.bde.org> References: <1773157955.158922767.1452698181137.JavaMail.zimbra@uoguelph.ca> <1351730674.159022044.1452699617235.JavaMail.zimbra@uoguelph.ca> <20160114092934.GL72455@kib.kiev.ua> <964333498.161527381.1452827658163.JavaMail.zimbra@uoguelph.ca> <20160115095749.GC3942@kib.kiev.ua> <1817287612.162823118.1452909605928.JavaMail.zimbra@uoguelph.ca> <20160116191116.GI3942@kib.kiev.ua> <853868666.163292727.1452986431921.JavaMail.zimbra@uoguelph.ca> <20160117035858.GO3942@kib.kiev.ua> <20160117172549.C11309@besplex.bde.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sun, Jan 17, 2016 at 06:35:43PM +1100, Bruce Evans wrote:
> Setting IO_UNIT for all file types in vn_write() is not so good. Too
> many file types that can't support it go through vn_write(). It should
> be an error for them, but is just ignored. Some file types like pipes
> could reasonably try to support it if it is set. E.g., {PIPE_BUF}
> gives the normal limit of for atomic writes on pipes, bug it would
> be reasonable to use IO_UNIT to specify trying to do larger atomic
> writes and failing if this is not possible.
Pipes and most other special things, and even cdevs, do not perform
io throught {vn,VOP}_{read,write}. The vnode bypass is common and
usually that things io is routed through the file ops.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20160117080853.GP3942>