Commit Graph

53 Commits

Author SHA1 Message Date
Al Viro
157cf649a7 sanitize audit_fd_pair()
* no allocations
* return void

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:41 -05:00
David Howells
da9592edeb CRED: Wrap task credential accesses in the filesystem subsystem
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.

Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:05 +11:00
Al Viro
233e70f422 saner FASYNC handling on file close
As it is, all instances of ->release() for files that have ->fasync()
need to remember to evict file from fasync lists; forgetting that
creates a hole and we actually have a bunch that *does* forget.

So let's keep our lives simple - let __fput() check FASYNC in
file->f_flags and call ->fasync() there if it's been set.  And lose that
crap in ->release() instances - leaving it there is still valid, but we
don't have to bother anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-01 09:49:46 -07:00
Denys Vlasenko
d2d9648ec6 [PATCH] reuse xxx_fifo_fops for xxx_pipe_fops
Merge fifo and pipe file_operations.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:06 -04:00
Ulrich Drepper
be61a86d72 flag parameters: NONBLOCK in pipe
This patch adds O_NONBLOCK support to pipe2.  It is minimally more involved
than the patches for eventfd et.al but still trivial.  The interfaces of the
create_write_pipe and create_read_pipe helper functions were changed and the
one other caller as well.

The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>

#ifndef __NR_pipe2
# ifdef __x86_64__
#  define __NR_pipe2 293
# elif defined __i386__
#  define __NR_pipe2 331
# else
#  error "need __NR_pipe2"
# endif
#endif

int
main (void)
{
  int fds[2];
  if (syscall (__NR_pipe2, fds, 0) == -1)
    {
      puts ("pipe2(0) failed");
      return 1;
    }
  for (int i = 0; i < 2; ++i)
    {
      int fl = fcntl (fds[i], F_GETFL);
      if (fl == -1)
        {
          puts ("fcntl failed");
          return 1;
        }
      if (fl & O_NONBLOCK)
        {
          printf ("pipe2(0) set non-blocking mode for fds[%d]\n", i);
          return 1;
        }
      close (fds[i]);
    }

  if (syscall (__NR_pipe2, fds, O_NONBLOCK) == -1)
    {
      puts ("pipe2(O_NONBLOCK) failed");
      return 1;
    }
  for (int i = 0; i < 2; ++i)
    {
      int fl = fcntl (fds[i], F_GETFL);
      if (fl == -1)
        {
          puts ("fcntl failed");
          return 1;
        }
      if ((fl & O_NONBLOCK) == 0)
        {
          printf ("pipe2(O_NONBLOCK) does not set non-blocking mode for fds[%d]\n", i);
          return 1;
        }
      close (fds[i]);
    }

  puts ("OK");

  return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:29 -07:00
Ulrich Drepper
ed8cae8ba0 flag parameters: pipe
This patch introduces the new syscall pipe2 which is like pipe but it also
takes an additional parameter which takes a flag value.  This patch implements
the handling of O_CLOEXEC for the flag.  I did not add support for the new
syscall for the architectures which have a special sys_pipe implementation.  I
think the maintainers of those archs have the chance to go with the unified
implementation but that's up to them.

The implementation introduces do_pipe_flags.  I did that instead of changing
all callers of do_pipe because some of the callers are written in assembler.
I would probably screw up changing the assembly code.  To avoid breaking code
do_pipe is now a small wrapper around do_pipe_flags.  Once all callers are
changed over to do_pipe_flags the old do_pipe function can be removed.

The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>

#ifndef __NR_pipe2
# ifdef __x86_64__
#  define __NR_pipe2 293
# elif defined __i386__
#  define __NR_pipe2 331
# else
#  error "need __NR_pipe2"
# endif
#endif

int
main (void)
{
  int fd[2];
  if (syscall (__NR_pipe2, fd, 0) != 0)
    {
      puts ("pipe2(0) failed");
      return 1;
    }
  for (int i = 0; i < 2; ++i)
    {
      int coe = fcntl (fd[i], F_GETFD);
      if (coe == -1)
        {
          puts ("fcntl failed");
          return 1;
        }
      if (coe & FD_CLOEXEC)
        {
          printf ("pipe2(0) set close-on-exit for fd[%d]\n", i);
          return 1;
        }
    }
  close (fd[0]);
  close (fd[1]);

  if (syscall (__NR_pipe2, fd, O_CLOEXEC) != 0)
    {
      puts ("pipe2(O_CLOEXEC) failed");
      return 1;
    }
  for (int i = 0; i < 2; ++i)
    {
      int coe = fcntl (fd[i], F_GETFD);
      if (coe == -1)
        {
          puts ("fcntl failed");
          return 1;
        }
      if ((coe & FD_CLOEXEC) == 0)
        {
          printf ("pipe2(O_CLOEXEC) does not set close-on-exit for fd[%d]\n", i);
          return 1;
        }
    }
  close (fd[0]);
  close (fd[1]);

  puts ("OK");

  return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:28 -07:00
Jan Blunck
c8e7f449b2 [patch 1/4] vfs: path_{get,put}() cleanups
Here are some more places where path_{get,put}() can be used instead of
dput()/mntput() pair.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 11:52:29 -04:00
Ulrich Drepper
ba719baeab sys_pipe(): fix file descriptor leaks
Remember to close the files if copy_to_user() failed.

Spotted by dm.n9107@gmail.com.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Cc: DM <dm.n9107@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-08 10:46:56 -07:00
Ulrich Drepper
d35c7b0e54 unified (weak) sys_pipe implementation
This replaces the duplicated arch-specific versions of "sys_pipe()" with
one unified implementation.  This removes almost 250 lines of duplicated
code.

It's marked __weak, so that *if* an architecture wants to override the
default implementation it can do so by simply having its own replacement
version, since many architectures use alternate calling conventions for
the 'pipe()' system call for legacy reasons (ie traditional UNIX
implementations often return the two file descriptors in registers)

I still haven't changed the cris version even though Linus says the BKL
isn't needed.  The arch maintainer can easily do it if there are really
no obstacles.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-03 13:50:33 -07:00
Al Viro
ed15243717 [PATCH] double-free of inode on alloc_file() failure exit in create_write_pipe()
Duh...  Fortunately, the bug is quite recent (post-2.6.25) and, embarrassingly,
mine ;-/

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-22 19:54:57 -04:00
Dave Hansen
430e285e08 [PATCH] fix up new filp allocators
Some new uses of get_empty_filp() have crept in; switched
to alloc_file() to make sure that pieces of initialization
won't be missing.

We really need to kill get_empty_filp().

[AV] fixed dentry leak on failure exit in anon_inode_getfd()

Cc: Erez Zadok <ezk@cs.sunysb.edu>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J Bruce Fields" <bfields@fieldses.org>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-19 06:54:05 -04:00
Randy Dunlap
b51d63c6d3 kernel-doc: fix fs/pipe.c notation
Fix several kernel-doc notation errors in fs/pipe.c.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-13 16:21:19 -08:00
Andi Kleen
d59d0b1b88 BKL-Removal: convert pipe to use unlocked_ioctl too
No BKL needed in pipe_ioctl

Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:38 -08:00
Ingo Molnar
71e20f1873 sched: affine sync wakeups
make sync wakeups affine for cache-cold tasks: if a cache-cold task
is woken up by a sync wakeup then use the opportunity to migrate it
straight away. (the two tasks are 'related' because they communicate)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-15 17:00:19 +02:00
Mike Galbraith
af92723262 sched: cleanup, remove the TASK_NONINTERACTIVE flag
Here's another piece of low hanging obsolete fruit.

Remove obsolete TASK_NONINTERACTIVE.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-15 17:00:13 +02:00
Randy Dunlap
79685b8dee docbook: add pipes, other fixes
Fix some typos in pipe.c and splice.c.
Add pipes API to kernel-api.tmpl.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-27 08:08:51 +02:00
Jens Axboe
0845718daf pipe: add documentation and comments
As per Andrew Mortons request, here's a set of documentation for
the generic pipe_buf_operations hooks, the pipe, and pipe_buffer
structures.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-10 08:04:16 +02:00
Jens Axboe
cac36bb06e pipe: change the ->pin() operation to ->confirm()
The name 'pin' was badly chosen, it doesn't pin a pipe buffer
in the most commonly used sense in the kernel. So change the
name to 'confirm', after debating this issue with Hugh
Dickins a bit.

A good return from ->confirm() means that the buffer is really
there, and that the contents are good.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-10 08:04:15 +02:00
Eric Dumazet
c23fbb6bcb VFS: delay the dentry name generation on sockets and pipes
1) Introduces a new method in 'struct dentry_operations'.  This method
   called d_dname() might be called from d_path() to build a pathname for
   special filesystems.  It is called without locks.

   Future patches (if we succeed in having one common dentry for all
   pipes/sockets) may need to change prototype of this method, but we now
   use : char *d_dname(struct dentry *dentry, char *buffer, int buflen);

2) Adds a dynamic_dname() helper function that eases d_dname() implementations

3) Defines d_dname method for sockets : No more sprintf() at socket
   creation.  This is delayed up to the moment someone does an access to
   /proc/pid/fd/...

4) Defines d_dname method for pipes : No more sprintf() at pipe
   creation.  This is delayed up to the moment someone does an access to
   /proc/pid/fd/...

A benchmark consisting of 1.000.000 calls to pipe()/close()/close() gives a
*nice* speedup on my Pentium(M) 1.6 Ghz :

3.090 s instead of 3.450 s

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:03 -07:00
Al Viro
db3495099d [PATCH] AUDIT_FD_PAIR
Provide an audit record of the descriptor pair returned by pipe() and
socketpair().  Rewritten from the original posted to linux-audit by
John D. Ramsdell <ramsdell@mitre.org>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-02-17 21:30:15 -05:00
Al Viro
5ccac88eeb [PATCH] fix leaks on pipe(2) failure exits
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-21 00:16:03 -08:00
Eric Dumazet
d4c3cca941 [PATCH] constify pipe_buf_operations
- pipe/splice should use const pipe_buf_operations and file_operations

- struct pipe_inode_info has an unused field "start" : get rid of it.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:47 -08:00
Josef "Jeff" Sipek
0f7fc9e4d0 [PATCH] VFS: change struct file to use struct path
This patch changes struct file to use struct path instead of having
independent pointers to struct dentry and struct vfsmount, and converts all
users of f_{dentry,vfsmnt} in fs/ to use f_path.{dentry,mnt}.

Additionally, it adds two #define's to make the transition easier for users of
the f_dentry and f_vfsmnt.

Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:41 -08:00
Eric Dumazet
d18de5a272 [PATCH] don't insert pipe dentries into dentry_hashtable.
We currently insert pipe dentries into the global dentry hashtable.  This
is suboptimal because there is currently no way these entries can be used
for a lookup().  (/proc/xxx/fd/xxx uses a different mechanism).  Inserting
them in dentry hashtable slows dcache lookups.

To let __dpath() still work correctly (ie not adding a " (deleted)") after
dentry name, we do :

 - Right after d_alloc(), pretend they are hashed by clearing the
   DCACHE_UNHASHED bit.

 - Call d_instantiate() instead of d_add() : dentry is not inserted in
   hash table.

__dpath() & friends work as intended during dentry lifetime.

 - At dismantle time, once dput() must clear the dentry, setting again
   DCACHE_UNHASHED bit inside the custom d_delete() function provided by
   pipe code, so that dput() can just kill_it.

This patch, combined with (avoid RCU for never hashed dentries) reduced
time of { pipe(p); close(p[0]); close(p[1]);} on my UP machine (1.6GHz
Pentium-M) from 3.23 us to 2.86 us (But this patch does not depend on other
patches, only bench results)

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:41 -08:00
Andi Kleen
d6cbd281d1 [PATCH] Some cleanup in the pipe code
Split the big and hard to read do_pipe function into smaller pieces.

This creates new create_write_pipe/free_write_pipe/create_read_pipe
functions.  These functions are made global so that they can be used by
other parts of the kernel.

The resulting code is more generic and easier to read and has cleaner error
handling and less gotos.

[akpm@osdl.org: cleanup]
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:33 -07:00
Badari Pulavarty
ee0b3e671b [PATCH] Remove readv/writev methods and use aio_read/aio_write instead
This patch removes readv() and writev() methods and replaces them with
aio_read()/aio_write() methods.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:28 -07:00
Theodore Ts'o
ba52de123d [PATCH] inode-diet: Eliminate i_blksize from the inode structure
This eliminates the i_blksize field from struct inode.  Filesystems that want
to provide a per-inode st_blksize can do so by providing their own getattr
routine instead of using the generic_fillattr() function.

Note that some filesystems were providing pretty much random (and incorrect)
values for i_blksize.

[bunk@stusta.de: cleanup]
[akpm@osdl.org: generic_fillattr() fix]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:18 -07:00
David Howells
454e2398be [PATCH] VFS: Permit filesystem to override root dentry on mount
Extend the get_sb() filesystem operation to take an extra argument that
permits the VFS to pass in the target vfsmount that defines the mountpoint.

The filesystem is then required to manually set the superblock and root dentry
pointers.  For most filesystems, this should be done with simple_set_mnt()
which will set the superblock pointer and then set the root dentry to the
superblock's s_root (as per the old default behaviour).

The get_sb() op now returns an integer as there's now no need to return the
superblock pointer.

This patch permits a superblock to be implicitly shared amongst several mount
points, such as can be done with NFS to avoid potential inode aliasing.  In
such a case, simple_set_mnt() would not be called, and instead the mnt_root
and mnt_sb would be set directly.

The patch also makes the following changes:

 (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
     pointer argument and return an integer, so most filesystems have to change
     very little.

 (*) If one of the convenience function is not used, then get_sb() should
     normally call simple_set_mnt() to instantiate the vfsmount. This will
     always return 0, and so can be tail-called from get_sb().

 (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
     dcache upon superblock destruction rather than shrink_dcache_anon().

     This is required because the superblock may now have multiple trees that
     aren't actually bound to s_root, but that still need to be cleaned up. The
     currently called functions assume that the whole tree is rooted at s_root,
     and that anonymous dentries are not the roots of trees which results in
     dentries being left unculled.

     However, with the way NFS superblock sharing are currently set to be
     implemented, these assumptions are violated: the root of the filesystem is
     simply a dummy dentry and inode (the real inode for '/' may well be
     inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
     with child trees.

     [*] Anonymous until discovered from another tree.

 (*) The documentation has been adjusted, including the additional bit of
     changing ext2_* into foo_* in the documentation.

[akpm@osdl.org: convert ipath_fs, do other stuff]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:45 -07:00
Jens Axboe
330ab71619 [PATCH] vmsplice: restrict stealing a little more
Apply the same rules as the anon pipe pages, only allow stealing
if no one else is using the page.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-05-02 15:29:57 +02:00
Jens Axboe
f6762b7ad8 [PATCH] pipe: enable atomic copying of pipe data to/from user space
The pipe ->map() method uses kmap() to virtually map the pages, which
is both slow and has known scalability issues on SMP. This patch enables
atomic copying of pipe pages, by pre-faulting data and using kmap_atomic()
instead.

lmbench bw_pipe and lat_pipe measurements agree this is a Good Thing. Here
are results from that on a UP machine with highmem (1.5GiB of RAM), running
first a UP kernel, SMP kernel, and SMP kernel patched.

Vanilla-UP:
Pipe bandwidth: 1622.28 MB/sec
Pipe bandwidth: 1610.59 MB/sec
Pipe bandwidth: 1608.30 MB/sec
Pipe latency: 7.3275 microseconds
Pipe latency: 7.2995 microseconds
Pipe latency: 7.3097 microseconds

Vanilla-SMP:
Pipe bandwidth: 1382.19 MB/sec
Pipe bandwidth: 1317.27 MB/sec
Pipe bandwidth: 1355.61 MB/sec
Pipe latency: 9.6402 microseconds
Pipe latency: 9.6696 microseconds
Pipe latency: 9.6153 microseconds

Patched-SMP:
Pipe bandwidth: 1578.70 MB/sec
Pipe bandwidth: 1579.95 MB/sec
Pipe bandwidth: 1578.63 MB/sec
Pipe latency: 9.1654 microseconds
Pipe latency: 9.2266 microseconds
Pipe latency: 9.1527 microseconds

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-05-01 20:02:05 +02:00
Jens Axboe
f84d751994 [PATCH] pipe: introduce ->pin() buffer operation
The ->map() function is really expensive on highmem machines right now,
since it has to use the slower kmap() instead of kmap_atomic(). Splice
rarely needs to access the virtual address of a page, so it's a waste
of time doing it.

Introduce ->pin() to take over the responsibility of making sure the
page data is valid. ->map() is then reduced to just kmap(). That way we
can also share a most of the pipe buffer ops between pipe.c and splice.c

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-05-01 19:59:03 +02:00
Jens Axboe
0568b409c7 [PATCH] splice: fix bugs in pipe_to_file()
Found by Oleg Nesterov <oleg@tv-sign.ru>, fixed by me.

- Only allow full pages to go to the page cache.
- Check page != buf->page instead of using PIPE_BUF_FLAG_STOLEN.
- Remember to clear 'stolen' if add_to_page_cache() fails.

And as a cleanup on that:

- Make the bottom fall-through logic a little less convoluted. Also make
  the steal path hold an extra reference to the page, so we don't have
  to differentiate between stolen and non-stolen at the end.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-05-01 19:50:48 +02:00
Jens Axboe
46e678c96b [PATCH] splice: fix bugs with stealing regular pipe pages
- Check that page has suitable count for stealing in the regular pipes.
- pipe_to_file() assumes that the page is locked on succesful steal, so
  do that in the pipe steal hook
- Missing unlock_page() in add_to_page_cache() failure.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-30 16:36:32 +02:00
Jens Axboe
70524490ee [PATCH] splice: add support for sys_tee()
Basically an in-kernel implementation of tee, which uses splice and the
pipe buffers as an intelligent way to pass data around by reference.

Where the user space tee consumes the input and produces a stdout and
file output, this syscall merely duplicates the data inside a pipe to
another pipe. No data is copied, the output just grabs a reference to the
input pipe data.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-11 15:51:17 +02:00
Ingo Molnar
341b446bc5 [PATCH] another round of fs/pipe.c cleanups
make pipe.c a bit more readable and hackable.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-11 13:57:45 +02:00
Ingo Molnar
923f4f2394 [PATCH] pipe.c/fifo.c code cleanups
more code cleanups after the macro conversion:

 - standardize on 'struct pipe_inode_info *pipe' variable names
 - introduce 'pipe' temporaries to reduce mass inode->i_pipe dereferencing

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-11 13:53:33 +02:00
Ingo Molnar
9aeedfc471 [PATCH] get rid of the PIPE_*() macros
get rid of the PIPE_*() macros. Scripted transformation.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-11 13:53:10 +02:00
Jens Axboe
b92ce55893 [PATCH] splice: add direct fd <-> fd splicing support
It's more efficient for sendfile() emulation. Basically we cache an
internal private pipe and just use that as the intermediate area for
pages. Direct splicing is not available from sys_splice(), it is only
meant to be used for sendfile() emulation.

Additional patch from Ingo Molnar to avoid the PIPE_BUFFERS loop at
exit for the normal fast path.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-11 13:52:07 +02:00
Ingo Molnar
3a326a2ce8 [PATCH] introduce a "kernel-internal pipe object" abstraction
separate out the 'internal pipe object' abstraction, and make it
usable to splice. This cleans up and fixes several aspects of the
internal splice APIs and the pipe code:

 - pipes: the allocation and freeing of pipe_inode_info is now more symmetric
   and more streamlined with existing kernel practices.

 - splice: small micro-optimization: less pointer dereferencing in splice
   methods

Signed-off-by: Ingo Molnar <mingo@elte.hu>

Update XFS for the ->splice_read/->splice_write changes.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-10 15:18:35 +02:00
Jens Axboe
3e7ee3e7b3 [PATCH] splice: fix page stealing LRU handling.
Originally from Nick Piggin, just adapted to the newer branch.

You can't check PageLRU without holding zone->lru_lock.  The page
release code can get away with it only because the page refcount is 0 at
that point. Also, you can't reliably remove pages from the LRU unless
the refcount is 0. Ever.

Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-02 23:11:04 +02:00
Jens Axboe
4f6f0bd2ff [PATCH] splice: improve writeback and clean up page stealing
By cleaning up the writeback logic (killing write_one_page() and the manual
set_page_dirty()), we can get rid of ->stolen inside the pipe_buffer and
just keep it local in pipe_to_file().

This also adds dirty page balancing logic and O_SYNC handling.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-04-02 23:04:46 +02:00
Jens Axboe
5abc97aa25 [PATCH] splice: add support for SPLICE_F_MOVE flag
This enables the caller to migrate pages from one address space page
cache to another.  In buzz word marketing, you can do zero-copy file
copies!

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-30 12:28:18 -08:00
Jens Axboe
5274f052e7 [PATCH] Introduce sys_splice() system call
This adds support for the sys_splice system call. Using a pipe as a
transport, it can connect to files or sockets (latter as output only).

From the splice.c comments:

   "splice": joining two ropes together by interweaving their strands.

   This is the "extended pipe" functionality, where a pipe is used as
   an arbitrary in-memory buffer. Think of a pipe as a small kernel
   buffer that you can use to transfer data from one end to the other.

   The traditional unix read/write is extended with a "splice()" operation
   that transfers data buffers to or from a pipe buffer.

   Named by Larry McVoy, original implementation from Linus, extended by
   Jens to support splicing to files and fixing the initial implementation
   bugs.

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-30 12:28:18 -08:00
Arjan van de Ven
4b6f5d20b0 [PATCH] Make most file operations structs in fs/ const
This is a conversion to make the various file_operations structs in fs/
const.  Basically a regexp job, with a few manual fixups

The goal is both to increase correctness (harder to accidentally write to
shared datastructures) and reducing the false sharing of cachelines with
things that get dirty in .data (while .rodata is nicely read only and thus
cache clean)

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:06 -08:00
Eric Dumazet
fa3536cc14 [PATCH] Use __read_mostly on some hot fs variables
I discovered on oprofile hunting on a SMP platform that dentry lookups were
slowed down because d_hash_mask, d_hash_shift and dentry_hashtable were in
a cache line that contained inodes_stat.  So each time inodes_stats is
changed by a cpu, other cpus have to refill their cache line.

This patch moves some variables to the __read_mostly section, in order to
avoid false sharing.  RCU dentry lookups can go full speed.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:56 -08:00
Oliver Neukum
11b0b5abb2 [PATCH] use kzalloc and kcalloc in core fs code
Signed-off-by: Oliver Neukum <oliver@neukum.name>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:23:00 -08:00
Linus Torvalds
a19cbd4bf2 Mark the pipe file operations static
They aren't used (nor even really usable) outside of pipe.c anyway

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-08 14:03:09 -08:00
Arjan van de Ven
858119e159 [PATCH] Unlinline a bunch of other functions
Remove the "inline" keyword from a bunch of big functions in the kernel with
the goal of shrinking it by 30kb to 40kb

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:06 -08:00
Christoph Hellwig
870f481793 [PATCH] replace inode_update_time with file_update_time
To allow various options to work per-mount instead of per-sb we need a
struct vfsmount when updating ctime and mtime.  This preparation patch
replaces the inode_update_time routine with a file_update_atime routine so
we can easily get at the vfsmount.  (and the file makes more sense in this
context anyway).  Also get rid of the unused second argument - we always
want to update the ctime when calling this routine.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:30 -08:00
Jes Sorensen
1b1dcc1b57 [PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-09 15:59:24 -08:00