From: Al Viro <viro@ZenIV.linux.org.uk>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Kernel development list <linux-kernel@vger.kernel.org>
Subject: Re: How to tell whether a struct file is held by a process?
Date: Thu, 21 May 2009 10:52:17 +0100 [thread overview]
Message-ID: <20090521095217.GU8633@ZenIV.linux.org.uk> (raw)
In-Reply-To: <Pine.LNX.4.44L0.0905191251170.10557-100000@iolanthe.rowland.org>
On Tue, May 19, 2009 at 12:57:21PM -0400, Alan Stern wrote:
> What's the best way to tell whether the current process has a
> particular struct file among its open files? Is there any better way
> to find out than blindly calling fget() for each possible fd?
>
> Is this a totally insane thing to do?
It is insane. You might lock fdtable and scan it, but as soon as you
drop the spinlock your return value is worthless.
What are you trying to do? If the process is cooperating, you don't really
need that in the kernel, if it's not, the check is not usable...
next prev parent reply other threads:[~2009-05-21 9:52 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-19 16:57 How to tell whether a struct file is held by a process? Alan Stern
2009-05-21 9:52 ` Al Viro [this message]
2009-05-21 14:06 ` Alan Stern
2009-05-21 21:07 ` Kay Sievers
2009-05-21 21:27 ` Alan Stern
2009-05-22 13:30 ` Pantelis Koukousoulas
2009-05-22 13:38 ` Oliver Neukum
2009-05-22 13:43 ` Alan Cox
2009-05-22 13:52 ` Pantelis Koukousoulas
2009-05-22 14:12 ` Alan Cox
2009-05-22 14:29 ` Pantelis Koukousoulas
2009-05-21 22:14 ` Alan Cox
2009-05-22 1:28 ` Kyle Moffett
2009-05-22 9:53 ` Alan Cox
2009-05-22 15:12 ` Alan Stern
2009-05-22 15:20 ` Alan Cox
2009-05-22 16:04 ` Alan Stern
2009-05-22 16:23 ` Pantelis Koukousoulas
2009-05-22 18:19 ` Alan Stern
2009-05-22 15:21 ` Kay Sievers
2009-05-22 15:54 ` Alan Stern
2009-05-22 18:24 ` Kay Sievers
2009-05-22 18:48 ` Pantelis Koukousoulas
2009-05-22 19:31 ` Alan Stern
2009-05-22 21:54 ` Kay Sievers
2009-05-22 22:07 ` Alan Stern
2009-05-23 22:47 ` Kay Sievers
2009-05-22 8:36 ` Oliver Neukum
2009-05-21 22:22 ` Alan Cox
2009-05-22 12:26 ` Oliver Neukum
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