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From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	Joel Becker <jlbec@evilplan.org>,
	Chris Mason <chris.mason@oracle.com>,
	David Miller <davem@davemloft.net>
Subject: Re: [RFC] killing boilerplate checks in ->link/->mkdir/->rename
Date: Fri, 3 Feb 2012 01:45:33 +0000	[thread overview]
Message-ID: <20120203014533.GT23916@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20120203011612.GS23916@ZenIV.linux.org.uk>

On Fri, Feb 03, 2012 at 01:16:12AM +0000, Al Viro wrote:

> After looking a bit more: nlink_t is a f*cking mess.  Almost any code
> using that type kernel-side is broken.  Crap galore:
> 	* sometimes it's 32 bits, sometimes 16, sometimes 64.  Essentially
> at random.
> 	* almost all have it unsigned, except for sparc32, where it's
> signed short [inherited from v7 via SunOS?  BTW, in v6 it used to be even
> funnier - char, which is where ridiculous LINK_MAX == 127 comes from]
> 
> IOW, nlink_t is an attractive nuisance - it's nearly impossible to use in
> a portable way and we are lucky that almost nobody tries to.

Incidentally, why the hell do we have
	typedef __kernel_nlink_t        nlink_t;
anyway?  It's *not* exposed to userland and it's different from the
userland nlink_t (which is unsigned int on 32bit and unsigned long on 64bit).
Why not use __kernel_nlink_t (or explicitly-sized __uNN) in
arch/*/include/asm/stat.h and declare nlink_t kernel-side as __u32?

Why do we have daddr_t, while we are at it?  There is exactly one user -
fs/freevxfs and there we definitely want a fixed-sized type.

  reply	other threads:[~2012-02-03  1:45 UTC|newest]

Thread overview: 75+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-30 21:56 sysfs regression: wrong link counts Jiri Slaby
2012-01-30 22:06 ` Greg KH
2012-01-30 22:10   ` Alan Cox
2012-01-30 22:27     ` Greg KH
2012-01-30 22:43       ` Al Viro
2012-01-30 22:56         ` Al Viro
2012-01-31  1:27       ` Eric W. Biederman
2012-01-31 10:48         ` Jiri Slaby
2012-01-31 12:44           ` Eric W. Biederman
2012-01-31 16:45             ` Linus Torvalds
2012-01-31 19:18               ` Al Viro
2012-02-01  5:06               ` Eric W. Biederman
2012-02-01 22:21                 ` [PATCH] sysfs: Optionally count subdirectories to support buggy applications Eric W. Biederman
2012-02-01 22:24                   ` Greg Kroah-Hartman
2012-02-01 22:44                     ` Eric W. Biederman
2012-02-01 22:49                       ` Greg Kroah-Hartman
2012-02-01 22:31                   ` Dave Jones
2012-02-01 22:35                   ` Jiri Slaby
2012-02-01 23:15                   ` Linus Torvalds
2012-02-01 23:18                     ` Linus Torvalds
2012-02-02  1:22                       ` Al Viro
2012-02-02 21:24                         ` [RFC] killing boilerplate checks in ->link/->mkdir/->rename Al Viro
2012-02-02 23:46                           ` Linus Torvalds
2012-02-03  1:16                             ` Al Viro
2012-02-03  1:45                               ` Al Viro [this message]
2012-02-03  2:00                                 ` Linus Torvalds
2012-02-03 14:57                               ` Chris Mason
2012-02-03 17:08                               ` Al Viro
2012-02-03 19:34                                 ` Artem Bityutskiy
2012-02-06  8:50                                 ` Artem Bityutskiy
2012-02-06 13:56                                   ` Al Viro
2012-02-06 17:05                                     ` Artem Bityutskiy
2012-02-06 17:11                                       ` Al Viro
2012-02-07  7:21                                         ` Artem Bityutskiy
2012-02-06 22:49                               ` Dave Chinner
2012-02-03  8:25                           ` Andreas Dilger
2012-02-03 17:03                             ` Al Viro
2012-02-04  7:42                               ` Andreas Dilger
2012-03-05 13:30                       ` [PATCH] sysfs: Optionally count subdirectories to support buggy applications Jiri Slaby
2012-03-05 16:09                         ` Greg Kroah-Hartman
2012-03-05 16:47                           ` Linus Torvalds
2012-03-08 21:05                             ` Greg Kroah-Hartman
2012-03-08 22:18                             ` Eric W. Biederman
2012-03-08 23:40                               ` Linus Torvalds
2012-03-08 21:28                           ` Eric W. Biederman
2012-03-08 21:34                           ` [PATCH 1/3] sysfs: Compact sysfs_dirent s_flags into a byte Eric W. Biederman
2012-03-08 21:36                             ` [PATCH 2/3] sysfs: Maintain usable nlink directory counts Eric W. Biederman
2012-03-08 21:37                               ` [PATCH 3/3] sysfs: Remove SYSFS_FLAG_REMOVED and use sd->s_nlink == 0 instead Eric W. Biederman
2012-03-09  3:40                                 ` Linus Torvalds
2012-03-08 22:28                             ` [PATCH 1/3] sysfs: Compact sysfs_dirent s_flags into a byte Greg Kroah-Hartman
2012-03-09  2:49                               ` Eric W. Biederman
2012-01-31  3:45     ` sysfs regression: wrong link counts Eric W. Biederman
2012-01-31 11:54       ` Alan Cox
2012-01-30 22:52 ` Kay Sievers
2012-01-31 10:41   ` network regression: cannot rename netdev twice Jiri Slaby
2012-01-31 10:52     ` Kay Sievers
2012-01-31 11:00       ` Jiri Slaby
2012-01-31 11:13         ` Kay Sievers
2012-01-31 11:17           ` Jiri Slaby
2012-01-31 11:58             ` Kay Sievers
2012-01-31 14:18               ` Eric W. Biederman
2012-01-31 14:40                 ` [PATCH] sysfs: Update the name hash when renaming sysfs entries Eric W. Biederman
2012-01-31 14:41                   ` Jiri Slaby
2012-01-31 14:55                   ` Greg KH
2012-02-04  2:14       ` network regression: cannot rename netdev twice Henrique de Moraes Holschuh
2012-02-06 20:03         ` Kay Sievers
2012-02-08  2:00           ` Henrique de Moraes Holschuh
2012-02-08  3:50             ` Kay Sievers
2012-02-08  6:42               ` Valdis.Kletnieks
2012-02-08 10:57                 ` Kay Sievers
2012-02-08 20:06                   ` Valdis.Kletnieks
2012-02-08 20:27                     ` Stephen Hemminger
2012-02-08 23:48                     ` Kay Sievers
2012-01-31  1:32 ` sysfs regression: wrong link counts Eric W. Biederman
2012-02-01 18:29 ` Maciej Rutecki

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