lkml.org 
[lkml]   [2012]   [Aug]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 1/9] procfs: Move /proc/pid/fd[info] handling code to fd.[ch]
On Sat, Aug 25, 2012 at 06:16:05PM +0100, Al Viro wrote:
> On Thu, Aug 23, 2012 at 02:43:24PM +0400, Cyrill Gorcunov wrote:
> > This patch prepares the ground for further extension of
> > /proc/pid/fd[info] handling code by moving fdinfo handling
> > code into fs/proc/fd.c.
> >
> > I think such move makes both fs/proc/base.c and fs/proc/fd.c
> > easier to read.
>
> BTW, looking at the other stuff in fs/proc/base.c, why the hell is
> struct file * grabbed in proc_map_files_readdir()? All we do with
> it is passing it to proc_fill_cache(), which passes it to
> proc_map_files_instantiate(), which looks at two sodding bits
> in file->f_mode. Then we go and fput() all those struct file
> references we'd been putting into the array... What for?

Another thing:
f_flags = fd_file->f_flags & ~O_CLOEXEC;
in there is really wrong; we shouldn't leak that bit into ->f_flags
at all (which is properly fixed in fs/open.c). Close-on-exec is
a property of descriptor, not of file...

tid_fd_revalidate(): these dances with get_files_struct()/put_files_struct()
are pointless. We really only need "is it opened" + f_mode if it is.
Extracting that information is cheap enough to have it done right under
task_lock() (see what get_files_struct() is doing); no need to mess with
files_struct refcount, etc.

proc_fd_link() and seq_fd_open(): ditto.

As the matter of fact, the only place in there where get_files_struct() is
warranted is proc_readfd_common().

intantiate callback: sodding atrocity; as the absolute minimum it should
lose its "dir" argument. dentry->d_parent->d_inode is stable (we are
holding ->i_mutex on parent in all callers) and it's equal to dir in all
cases.


\
 
 \ /
  Last update: 2012-08-26 02:01    [W:0.068 / U:0.332 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site