1. 01 Nov, 2008 1 commit
    • Al Viro's avatar
      saner FASYNC handling on file close · 233e70f4
      Al Viro authored
      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: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      233e70f4
  2. 27 Jul, 2008 1 commit
  3. 24 Jul, 2008 2 commits
    • Ulrich Drepper's avatar
      flag parameters: NONBLOCK in pipe · be61a86d
      Ulrich Drepper authored
      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: default avatarUlrich Drepper <drepper@redhat.com>
      Acked-by: default avatarDavide Libenzi <davidel@xmailserver.org>
      Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      be61a86d
    • Ulrich Drepper's avatar
      flag parameters: pipe · ed8cae8b
      Ulrich Drepper authored
      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: default avatarUlrich Drepper <drepper@redhat.com>
      Acked-by: default avatarDavide Libenzi <davidel@xmailserver.org>
      Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
      Cc: <linux-arch@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ed8cae8b
  4. 23 Jun, 2008 1 commit
  5. 08 May, 2008 1 commit
  6. 03 May, 2008 1 commit
    • Ulrich Drepper's avatar
      unified (weak) sys_pipe implementation · d35c7b0e
      Ulrich Drepper authored
      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: default avatarUlrich Drepper <drepper@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d35c7b0e
  7. 22 Apr, 2008 1 commit
  8. 19 Mar, 2008 1 commit
  9. 14 Feb, 2008 1 commit
  10. 08 Feb, 2008 1 commit
  11. 15 Oct, 2007 2 commits
  12. 27 Jul, 2007 1 commit
  13. 10 Jul, 2007 2 commits
  14. 08 May, 2007 1 commit
    • Eric Dumazet's avatar
      VFS: delay the dentry name generation on sockets and pipes · c23fbb6b
      Eric Dumazet authored
      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: default avatarEric Dumazet <dada1@cosmosbay.com>
      Acked-by: default avatarChristoph Hellwig <hch@infradead.org>
      Acked-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c23fbb6b
  15. 18 Feb, 2007 1 commit
    • Al Viro's avatar
      [PATCH] AUDIT_FD_PAIR · db349509
      Al Viro authored
      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: default avatarAl Viro <viro@zeniv.linux.org.uk>
      db349509
  16. 21 Dec, 2006 1 commit
  17. 13 Dec, 2006 1 commit
  18. 08 Dec, 2006 1 commit
  19. 07 Dec, 2006 1 commit
    • Eric Dumazet's avatar
      [PATCH] don't insert pipe dentries into dentry_hashtable. · d18de5a2
      Eric Dumazet authored
      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: default avatarEric Dumazet <dada1@cosmosbay.com>
      Acked-by: default avatarDavid Miller <davem@davemloft.net>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      d18de5a2
  20. 01 Oct, 2006 2 commits
  21. 27 Sep, 2006 1 commit
  22. 23 Jun, 2006 1 commit
    • David Howells's avatar
      [PATCH] VFS: Permit filesystem to override root dentry on mount · 454e2398
      David Howells authored
      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: default avatarDavid Howells <dhowells@redhat.com>
      Acked-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Cc: Nathan Scott <nathans@sgi.com>
      Cc: Roland Dreier <rolandd@cisco.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      454e2398
  23. 02 May, 2006 1 commit
  24. 01 May, 2006 3 commits
    • Jens Axboe's avatar
      [PATCH] pipe: enable atomic copying of pipe data to/from user space · f6762b7a
      Jens Axboe authored
      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: default avatarJens Axboe <axboe@suse.de>
      f6762b7a
    • Jens Axboe's avatar
      [PATCH] pipe: introduce ->pin() buffer operation · f84d7519
      Jens Axboe authored
      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: default avatarJens Axboe <axboe@suse.de>
      f84d7519
    • Jens Axboe's avatar
      [PATCH] splice: fix bugs in pipe_to_file() · 0568b409
      Jens Axboe authored
      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: default avatarJens Axboe <axboe@suse.de>
      0568b409
  25. 30 Apr, 2006 1 commit
  26. 11 Apr, 2006 5 commits
  27. 10 Apr, 2006 1 commit
    • Ingo Molnar's avatar
      [PATCH] introduce a "kernel-internal pipe object" abstraction · 3a326a2c
      Ingo Molnar authored
      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: default avatarIngo Molnar <mingo@elte.hu>
      
      Update XFS for the ->splice_read/->splice_write changes.
      Signed-off-by: default avatarJens Axboe <axboe@suse.de>
      3a326a2c
  28. 02 Apr, 2006 2 commits
  29. 30 Mar, 2006 1 commit