1. 14 Jun, 2018 1 commit
  2. 12 Jun, 2018 1 commit
    • Kees Cook's avatar
      treewide: kmalloc() -> kmalloc_array() · 6da2ec56
      Kees Cook authored
      The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
      patch replaces cases of:
      
              kmalloc(a * b, gfp)
      
      with:
              kmalloc_array(a * b, gfp)
      
      as well as handling cases of:
      
              kmalloc(a * b * c, gfp)
      
      with:
      
              kmalloc(array3_size(a, b, c), gfp)
      
      as it's slightly less ugly than:
      
              kmalloc_array(array_size(a, b), c, gfp)
      
      This does, however, attempt to ignore constant size factors like:
      
              kmalloc(4 * 1024, gfp)
      
      though any constants defined via macros get caught up in the conversion.
      
      Any factors with a sizeof() of "unsigned char", "char", and "u8" were
      dropped, since they're redundant.
      
      The tools/ directory was manually excluded, since it has its own
      implementation of kmalloc().
      
      The Coccinelle script used for this was:
      
      // Fix redundant parens around sizeof().
      @@
      type TYPE;
      expression THING, E;
      @@
      
      (
        kmalloc(
      -	(sizeof(TYPE)) * E
      +	sizeof(TYPE) * E
        , ...)
      |
        kmalloc(
      -	(sizeof(THING)) * E
      +	sizeof(THING) * E
        , ...)
      )
      
      // Drop single-byte sizes and redundant parens.
      @@
      expression COUNT;
      typedef u8;
      typedef __u8;
      @@
      
      (
        kmalloc(
      -	sizeof(u8) * (COUNT)
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(__u8) * (COUNT)
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(char) * (COUNT)
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(unsigned char) * (COUNT)
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(u8) * COUNT
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(__u8) * COUNT
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(char) * COUNT
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(unsigned char) * COUNT
      +	COUNT
        , ...)
      )
      
      // 2-factor product with sizeof(type/expression) and identifier or constant.
      @@
      type TYPE;
      expression THING;
      identifier COUNT_ID;
      constant COUNT_CONST;
      @@
      
      (
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * (COUNT_ID)
      +	COUNT_ID, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * COUNT_ID
      +	COUNT_ID, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * (COUNT_CONST)
      +	COUNT_CONST, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * COUNT_CONST
      +	COUNT_CONST, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * (COUNT_ID)
      +	COUNT_ID, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * COUNT_ID
      +	COUNT_ID, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * (COUNT_CONST)
      +	COUNT_CONST, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * COUNT_CONST
      +	COUNT_CONST, sizeof(THING)
        , ...)
      )
      
      // 2-factor product, only identifiers.
      @@
      identifier SIZE, COUNT;
      @@
      
      - kmalloc
      + kmalloc_array
        (
      -	SIZE * COUNT
      +	COUNT, SIZE
        , ...)
      
      // 3-factor product with 1 sizeof(type) or sizeof(expression), with
      // redundant parens removed.
      @@
      expression THING;
      identifier STRIDE, COUNT;
      type TYPE;
      @@
      
      (
        kmalloc(
      -	sizeof(TYPE) * (COUNT) * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE) * (COUNT) * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE) * COUNT * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE) * COUNT * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        kmalloc(
      -	sizeof(THING) * (COUNT) * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        kmalloc(
      -	sizeof(THING) * (COUNT) * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        kmalloc(
      -	sizeof(THING) * COUNT * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        kmalloc(
      -	sizeof(THING) * COUNT * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      )
      
      // 3-factor product with 2 sizeof(variable), with redundant parens removed.
      @@
      expression THING1, THING2;
      identifier COUNT;
      type TYPE1, TYPE2;
      @@
      
      (
        kmalloc(
      -	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
        , ...)
      |
        kmalloc(
      -	sizeof(THING1) * sizeof(THING2) * COUNT
      +	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
        , ...)
      |
        kmalloc(
      -	sizeof(THING1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * COUNT
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
        , ...)
      )
      
      // 3-factor product, only identifiers, with redundant parens removed.
      @@
      identifier STRIDE, SIZE, COUNT;
      @@
      
      (
        kmalloc(
      -	(COUNT) * STRIDE * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	COUNT * (STRIDE) * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	COUNT * STRIDE * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	(COUNT) * (STRIDE) * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	COUNT * (STRIDE) * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	(COUNT) * STRIDE * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	(COUNT) * (STRIDE) * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	COUNT * STRIDE * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      )
      
      // Any remaining multi-factor products, first at least 3-factor products,
      // when they're not all constants...
      @@
      expression E1, E2, E3;
      constant C1, C2, C3;
      @@
      
      (
        kmalloc(C1 * C2 * C3, ...)
      |
        kmalloc(
      -	(E1) * E2 * E3
      +	array3_size(E1, E2, E3)
        , ...)
      |
        kmalloc(
      -	(E1) * (E2) * E3
      +	array3_size(E1, E2, E3)
        , ...)
      |
        kmalloc(
      -	(E1) * (E2) * (E3)
      +	array3_size(E1, E2, E3)
        , ...)
      |
        kmalloc(
      -	E1 * E2 * E3
      +	array3_size(E1, E2, E3)
        , ...)
      )
      
      // And then all remaining 2 factors products when they're not all constants,
      // keeping sizeof() as the second factor argument.
      @@
      expression THING, E1, E2;
      type TYPE;
      constant C1, C2, C3;
      @@
      
      (
        kmalloc(sizeof(THING) * C2, ...)
      |
        kmalloc(sizeof(TYPE) * C2, ...)
      |
        kmalloc(C1 * C2 * C3, ...)
      |
        kmalloc(C1 * C2, ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * (E2)
      +	E2, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * E2
      +	E2, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * (E2)
      +	E2, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * E2
      +	E2, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	(E1) * E2
      +	E1, E2
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	(E1) * (E2)
      +	E1, E2
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	E1 * E2
      +	E1, E2
        , ...)
      )
      Signed-off-by: 's avatarKees Cook <keescook@chromium.org>
      6da2ec56
  3. 21 Feb, 2018 1 commit
  4. 11 Feb, 2018 1 commit
    • Linus Torvalds's avatar
      vfs: do bulk POLL* -> EPOLL* replacement · a9a08845
      Linus Torvalds authored
      This is the mindless scripted replacement of kernel use of POLL*
      variables as described by Al, done by this script:
      
          for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
              L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
              for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
          done
      
      with de-mangling cleanups yet to come.
      
      NOTE! On almost all architectures, the EPOLL* constants have the same
      values as the POLL* constants do.  But they keyword here is "almost".
      For various bad reasons they aren't the same, and epoll() doesn't
      actually work quite correctly in some cases due to this on Sparc et al.
      
      The next patch from Al will sort out the final differences, and we
      should be all done.
      Scripted-by: 's avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      a9a08845
  5. 07 Feb, 2018 1 commit
  6. 27 Nov, 2017 1 commit
  7. 28 Feb, 2017 1 commit
  8. 25 Feb, 2017 1 commit
  9. 27 Dec, 2016 1 commit
  10. 15 Dec, 2016 1 commit
  11. 11 Oct, 2016 1 commit
    • Peter Zijlstra's avatar
      relay: Use irq_work instead of plain timer for deferred wakeup · 26b5679e
      Peter Zijlstra authored
      Relay avoids calling wake_up_interruptible() for doing the wakeup of
      readers/consumers, waiting for the generation of new data, from the
      context of a process which produced the data.  This is apparently done to
      prevent the possibility of a deadlock in case Scheduler itself is is
      generating data for the relay, after acquiring rq->lock.
      
      The following patch used a timer (to be scheduled at next jiffy), for
      delegating the wakeup to another context.
      	commit 7c9cb383
      	Author: Tom Zanussi <zanussi@comcast.net>
      	Date:   Wed May 9 02:34:01 2007 -0700
      
      	relay: use plain timer instead of delayed work
      
      	relay doesn't need to use schedule_delayed_work() for waking readers
      	when a simple timer will do.
      
      Scheduling a plain timer, at next jiffies boundary, to do the wakeup
      causes a significant wakeup latency for the Userspace client, which makes
      relay less suitable for the high-frequency low-payload use cases where the
      data gets generated at a very high rate, like multiple sub buffers getting
      filled within a milli second.  Moreover the timer is re-scheduled on every
      newly produced sub buffer so the timer keeps getting pushed out if sub
      buffers are filled in a very quick succession (less than a jiffy gap
      between filling of 2 sub buffers).  As a result relay runs out of sub
      buffers to store the new data.
      
      By using irq_work it is ensured that wakeup of userspace client, blocked
      in the poll call, is done at earliest (through self IPI or next timer
      tick) enabling it to always consume the data in time.  Also this makes
      relay consistent with printk & ring buffers (trace), as they too use
      irq_work for deferred wake up of readers.
      
      [arnd@arndb.de: select CONFIG_IRQ_WORK]
       Link: http://lkml.kernel.org/r/20160912154035.3222156-1-arnd@arndb.de
      [akpm@linux-foundation.org: coding-style fixes]
      Link: http://lkml.kernel.org/r/1472906487-1559-1-git-send-email-akash.goel@intel.comSigned-off-by: 's avatarPeter Zijlstra <peterz@infradead.org>
      Signed-off-by: 's avatarAkash Goel <akash.goel@intel.com>
      Cc: Tom Zanussi <tzanussi@gmail.com>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
      Signed-off-by: 's avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      26b5679e
  12. 05 Oct, 2016 1 commit
  13. 06 Sep, 2016 2 commits
  14. 02 Aug, 2016 1 commit
    • Akash Goel's avatar
      relay: add global mode support for buffer-only channels · 59dbb2a0
      Akash Goel authored
      Commit 20d8b67c ("relay: add buffer-only channels; useful for early
      logging") added support to use channels with no associated files.
      
      This is useful when the exact location of relay file is not known or the
      the parent directory of relay file is not available, while creating the
      channel and the logging has to start right from the boot.
      
      But there was no provision to use global mode with buffer-only channels,
      which is added by this patch, without modifying the interface where
      initially there will be a dummy invocation of create_buf_file callback
      through which kernel client can convey the need of a global buffer.
      
      For the use case where drivers/kernel clients want a simple interface
      for the userspace, which enables them to capture data/logs from relay
      file inorder & without any post processing, support of Global buffer
      mode is warranted.
      
      Modules, like i915, using relay_open() in early init would have to later
      register their buffer-only relays, once debugfs is available, by calling
      relay_late_setup_files().  Hence relay_late_setup_files() symbol also
      needs to be exported.
      
      Link: http://lkml.kernel.org/r/1468404563-11653-1-git-send-email-akash.goel@intel.comSigned-off-by: 's avatarAkash Goel <akash.goel@intel.com>
      Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
      Cc: Tom Zanussi <tzanussi@gmail.com>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
      59dbb2a0
  15. 09 Jun, 2016 1 commit
  16. 22 Jan, 2016 1 commit
    • Al Viro's avatar
      wrappers for ->i_mutex access · 5955102c
      Al Viro authored
      parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
      inode_foo(inode) being mutex_foo(&inode->i_mutex).
      
      Please, use those for access to ->i_mutex; over the coming cycle
      ->i_mutex will become rwsem, with ->lookup() done with it held
      only shared.
      Signed-off-by: 's avatarAl Viro <viro@zeniv.linux.org.uk>
      5955102c
  17. 01 Jul, 2015 1 commit
  18. 15 Apr, 2015 1 commit
  19. 12 Apr, 2014 1 commit
  20. 02 Apr, 2014 1 commit
  21. 19 Feb, 2014 1 commit
  22. 14 Jul, 2013 1 commit
    • Paul Gortmaker's avatar
      kernel: delete __cpuinit usage from all core kernel files · 0db0628d
      Paul Gortmaker authored
      The __cpuinit type of throwaway sections might have made sense
      some time ago when RAM was more constrained, but now the savings
      do not offset the cost and complications.  For example, the fix in
      commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
      is a good example of the nasty type of bugs that can be created
      with improper use of the various __init prefixes.
      
      After a discussion on LKML[1] it was decided that cpuinit should go
      the way of devinit and be phased out.  Once all the users are gone,
      we can then finally remove the macros themselves from linux/init.h.
      
      This removes all the uses of the __cpuinit macros from C files in
      the core kernel directories (kernel, init, lib, mm, and include)
      that don't really have a specific maintainer.
      
      [1] https://lkml.org/lkml/2013/5/20/589Signed-off-by: 's avatarPaul Gortmaker <paul.gortmaker@windriver.com>
      0db0628d
  23. 01 May, 2013 3 commits
  24. 30 Apr, 2013 1 commit
    • Dmitry Monakhov's avatar
      relay: move remove_buf_file inside relay_close_buf · b8d4a5bf
      Dmitry Monakhov authored
      Currently remove_buf_file callback is called from from kobject
      release method. This result in follow issue:
      # blktrace -d /dev/sda1 -d /dev/sda -o test
      
      blktrace_setup()
       dir = create_dir()
       rchan = relay_open(dir,...)
       ->create_buf_file_callback
          buf_file  = debugfs_create_file(dir, )
      
      Userspace will open buf_file.
      Later we make a decision to stop tracing
      blktrace_down()
        relay_close(rhcan)  /* just decrement kobj reference  */
                            /* since it is not zero then callback not called */
        debugfs_remove(dir) /* FAIL due to non empty dir   */
      
      Later user space will close the file and file will be deleted,
      but directory still exist.
      user_space_close()
       ->file_release
         ->release_buf_file_callback
           ->debugfs_remove(buf_file
      ## TESTCASE:
      # blktrace -d /dev/sda1 -d /dev/sda -o test
      # After that blktrace infrastructure will remain broken in
      # an unusable state so: blktrace -d /dev/sda1 will not work.
      
      In fact this is general issue, blktrace is just one of examples.
      We can not reliably remove parent dir until all users close the
      buf_file.
      
      Solution: We don't have to wait that long. File should be deleted inside
      relay_close_buf().
      Signed-off-by: 's avatarDmitry Monakhov <dmonakhov@openvz.org>
      Signed-off-by: 's avatarJens Axboe <axboe@kernel.dk>
      b8d4a5bf
  25. 23 Feb, 2013 1 commit
  26. 13 Jun, 2012 1 commit
    • Eric Dumazet's avatar
      splice: fix racy pipe->buffers uses · 047fe360
      Eric Dumazet authored
      Dave Jones reported a kernel BUG at mm/slub.c:3474! triggered
      by splice_shrink_spd() called from vmsplice_to_pipe()
      
      commit 35f3d14d (pipe: add support for shrinking and growing pipes)
      added capability to adjust pipe->buffers.
      
      Problem is some paths don't hold pipe mutex and assume pipe->buffers
      doesn't change for their duration.
      
      Fix this by adding nr_pages_max field in struct splice_pipe_desc, and
      use it in place of pipe->buffers where appropriate.
      
      splice_shrink_spd() loses its struct pipe_inode_info argument.
      Reported-by: 's avatarDave Jones <davej@redhat.com>
      Signed-off-by: 's avatarEric Dumazet <edumazet@google.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Tom Herbert <therbert@google.com>
      Cc: stable <stable@vger.kernel.org> # 2.6.35
      Tested-by: 's avatarDave Jones <davej@redhat.com>
      Signed-off-by: 's avatarJens Axboe <axboe@kernel.dk>
      047fe360
  27. 10 Feb, 2012 1 commit
  28. 04 Jan, 2012 1 commit
  29. 31 Oct, 2011 1 commit
    • Paul Gortmaker's avatar
      kernel: Map most files to use export.h instead of module.h · 9984de1a
      Paul Gortmaker authored
      The changed files were only including linux/module.h for the
      EXPORT_SYMBOL infrastructure, and nothing else.  Revector them
      onto the isolated export header for faster compile times.
      
      Nothing to see here but a whole lot of instances of:
      
        -#include <linux/module.h>
        +#include <linux/export.h>
      
      This commit is only changing the kernel dir; next targets
      will probably be mm, fs, the arch dirs, etc.
      Signed-off-by: 's avatarPaul Gortmaker <paul.gortmaker@windriver.com>
      9984de1a
  30. 05 Nov, 2010 1 commit
  31. 27 May, 2010 1 commit
  32. 21 May, 2010 1 commit
  33. 06 Mar, 2010 1 commit
  34. 16 Dec, 2009 1 commit
  35. 27 Sep, 2009 1 commit
  36. 03 Apr, 2009 1 commit
  37. 18 Feb, 2009 1 commit
    • Ingo Molnar's avatar
      timers: add mod_timer_pending() · 74019224
      Ingo Molnar authored
      Impact: new timer API
      
      Based on an idea from Martin Josefsson with the help of
      Patrick McHardy and Stephen Hemminger:
      
      introduce the mod_timer_pending() API which is a mod_timer()
      offspring that is an invariant on already removed timers.
      
      (regular mod_timer() re-activates non-pending timers.)
      
      This is useful for the networking code in that it can
      allow unserialized mod_timer_pending() timer-forwarding
      calls, but a single del_timer*() will stop the timer
      from being reactivated again.
      
      Also while at it:
      
      - optimize the regular mod_timer() path some more, the
        timer-stat and a debug check was needlessly duplicated
        in __mod_timer().
      
      - make the exports come straight after the function, as
        most other exports in timer.c already did.
      
      - eliminate __mod_timer() as an external API, change the
        users to mod_timer().
      
      The regular mod_timer() code path is not impacted
      significantly, due to inlining optimizations and due to
      the simplifications.
      
      Based-on-patch-from: Stephen Hemminger <shemminger@vyatta.com>
      Acked-by: 's avatarStephen Hemminger <shemminger@vyatta.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Patrick McHardy <kaber@trash.net>
      Cc: netdev@vger.kernel.org
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Signed-off-by: 's avatarIngo Molnar <mingo@elte.hu>
      74019224