Re: [PATCH] hostfs: Use noop_fsync for directories

2015-01-17 Thread Daniel Gröber
From: Richard Weinberger Subject: Re: [PATCH] hostfs: Use noop_fsync for directories Date: Wed, 14 Jan 2015 09:43:53 +0100 > Daniel, are you interested in a small kernel project? Sure, I'm just pretty busy with university right now, I'll probably pick this back up after exams are

Re: [PATCH] hostfs: Use noop_fsync for directories

2015-01-14 Thread Richard Weinberger
Am 14.01.2015 um 09:39 schrieb Christoph Hellwig: > On Tue, Jan 13, 2015 at 11:26:38PM +0100, Richard Weinberger wrote: >> hostfs tries do reduce the amount of syscall between guest and host as much >> as possible. For file operations it passes everything down to the host but >> for directory opera

Re: [PATCH] hostfs: Use noop_fsync for directories

2015-01-14 Thread Christoph Hellwig
On Tue, Jan 13, 2015 at 11:26:38PM +0100, Richard Weinberger wrote: > hostfs tries do reduce the amount of syscall between guest and host as much > as possible. For file operations it passes everything down to the host but > for directory operations only ->iterate() does. > > It is already horribl

Re: [PATCH] hostfs: Use noop_fsync for directories

2015-01-13 Thread Richard Weinberger
Am 13.01.2015 um 23:19 schrieb Christoph Hellwig: > On Tue, Jan 13, 2015 at 11:15:58PM +0100, Richard Weinberger wrote: >> Daniel reported that dpkg(1) dies if the root filesystem is a hostfs >> because it does not expect fsync(2) to fail with EINVAL on directories. >> While fsync(2) is allowed to

Re: [PATCH] hostfs: Use noop_fsync for directories

2015-01-13 Thread Christoph Hellwig
On Tue, Jan 13, 2015 at 11:15:58PM +0100, Richard Weinberger wrote: > Daniel reported that dpkg(1) dies if the root filesystem is a hostfs > because it does not expect fsync(2) to fail with EINVAL on directories. > While fsync(2) is allowed to fail with EINVAL if the filesystem does not > support i

[PATCH] hostfs: Use noop_fsync for directories

2015-01-13 Thread Richard Weinberger
Daniel reported that dpkg(1) dies if the root filesystem is a hostfs because it does not expect fsync(2) to fail with EINVAL on directories. While fsync(2) is allowed to fail with EINVAL if the filesystem does not support it we can do better and use noop_fsync() to not confuse userspace further. C