kern/122838: [devfs] devfs doesn't handle complex paths (like zvol/pool/vms) good

[Jaakko Heinonen]

The following reply was made to PR kern/122838; it has been noted by GNATS.

From: Jaakko Heinonen <jh at FreeBSD.org>
To: Dmitry Marakasov <amdmi3 at amdmi3.ru>
Cc: bug-followup at FreeBSD.org
Subject: Re: kern/122838: [devfs] devfs doesn't handle complex paths (like
 zvol/pool/vms) good
Date: Wed, 8 Dec 2010 15:39:10 +0200

 On 2008-04-17, Dmitry Marakasov wrote:
 > devfs behavior on nested paths is really unintuitive and pretty hard to tune.
 
 I agree that the behavior of rules is confusing with directories.
 
 > Suppose I have ZFS zvol under pool/vms/win2000 and I want to unhide node for it in the jail.
 > 
 > Here's what it look like unhidden:
 > 
 > % find /dev/zvol
 > /dev/zvol
 > /dev/zvol/pool
 > /dev/zvol/pool/vms
 > /dev/zvol/pool/vms/win2000
 
 Following rules should do what you want:
 
 path zvol/* hide
 path zvol/pool/vms/win2000 unhide
 
 The problem is that for directories and symbolic links, rules match
 against single component name while for device files rules match against
 full device path (si_name). This may cause unwanted effects. For
 example, the rule "devfs fd hide" hides an entry /dev/label/fd/label.
  
 -- 
 Jaakko