1. 16 12月, 2009 9 次提交
  2. 11 12月, 2009 1 次提交
  3. 04 12月, 2009 1 次提交
  4. 12 11月, 2009 1 次提交
  5. 28 9月, 2009 1 次提交
  6. 24 9月, 2009 1 次提交
  7. 23 9月, 2009 1 次提交
  8. 22 9月, 2009 2 次提交
    • E
      hugetlbfs: allow the creation of files suitable for MAP_PRIVATE on the vfs internal mount · 6bfde05b
      Eric B Munson 提交于
      This patchset adds a flag to mmap that allows the user to request that an
      anonymous mapping be backed with huge pages.  This mapping will borrow
      functionality from the huge page shm code to create a file on the kernel
      internal mount and use it to approximate an anonymous mapping.  The
      MAP_HUGETLB flag is a modifier to MAP_ANONYMOUS and will not work without
      both flags being preset.
      
      A new flag is necessary because there is no other way to hook into huge
      pages without creating a file on a hugetlbfs mount which wouldn't be
      MAP_ANONYMOUS.
      
      To userspace, this mapping will behave just like an anonymous mapping
      because the file is not accessible outside of the kernel.
      
      This patchset is meant to simplify the programming model.  Presently there
      is a large chunk of boiler platecode, contained in libhugetlbfs, required
      to create private, hugepage backed mappings.  This patch set would allow
      use of hugepages without linking to libhugetlbfs or having hugetblfs
      mounted.
      
      Unification of the VM code would provide these same benefits, but it has
      been resisted each time that it has been suggested for several reasons: it
      would break PAGE_SIZE assumptions across the kernel, it makes page-table
      abstractions really expensive, and it does not provide any benefit on
      architectures that do not support huge pages, incurring fast path
      penalties without providing any benefit on these architectures.
      
      This patch:
      
      There are two means of creating mappings backed by huge pages:
      
              1. mmap() a file created on hugetlbfs
              2. Use shm which creates a file on an internal mount which essentially
                 maps it MAP_SHARED
      
      The internal mount is only used for shared mappings but there is very
      little that stops it being used for private mappings. This patch extends
      hugetlbfs_file_setup() to deal with the creation of files that will be
      mapped MAP_PRIVATE on the internal hugetlbfs mount. This extended API is
      used in a subsequent patch to implement the MAP_HUGETLB mmap() flag.
      Signed-off-by: NEric Munson <ebmunson@us.ibm.com>
      Acked-by: NDavid Rientjes <rientjes@google.com>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Adam Litke <agl@us.ibm.com>
      Cc: David Gibson <david@gibson.dropbear.id.au>
      Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
      Cc: Nick Piggin <nickpiggin@yahoo.com.au>
      Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      6bfde05b
    • A
  9. 15 9月, 2009 1 次提交
  10. 25 8月, 2009 1 次提交
    • H
      mm: fix hugetlb bug due to user_shm_unlock call · 353d5c30
      Hugh Dickins 提交于
      2.6.30's commit 8a0bdec1 removed
      user_shm_lock() calls in hugetlb_file_setup() but left the
      user_shm_unlock call in shm_destroy().
      
      In detail:
      Assume that can_do_hugetlb_shm() returns true and hence user_shm_lock()
      is not called in hugetlb_file_setup(). However, user_shm_unlock() is
      called in any case in shm_destroy() and in the following
      atomic_dec_and_lock(&up->__count) in free_uid() is executed and if
      up->__count gets zero, also cleanup_user_struct() is scheduled.
      
      Note that sched_destroy_user() is empty if CONFIG_USER_SCHED is not set.
      However, the ref counter up->__count gets unexpectedly non-positive and
      the corresponding structs are freed even though there are live
      references to them, resulting in a kernel oops after a lots of
      shmget(SHM_HUGETLB)/shmctl(IPC_RMID) cycles and CONFIG_USER_SCHED set.
      
      Hugh changed Stefan's suggested patch: can_do_hugetlb_shm() at the
      time of shm_destroy() may give a different answer from at the time
      of hugetlb_file_setup().  And fixed newseg()'s no_id error path,
      which has missed user_shm_unlock() ever since it came in 2.6.9.
      Reported-by: NStefan Huber <shuber2@gmail.com>
      Signed-off-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
      Tested-by: NStefan Huber <shuber2@gmail.com>
      Cc: stable@kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      353d5c30
  11. 29 6月, 2009 1 次提交
  12. 22 6月, 2009 1 次提交
  13. 19 6月, 2009 5 次提交
  14. 10 6月, 2009 1 次提交
  15. 22 5月, 2009 2 次提交
  16. 15 4月, 2009 1 次提交
  17. 14 4月, 2009 1 次提交
  18. 07 4月, 2009 3 次提交
  19. 03 4月, 2009 2 次提交
  20. 01 4月, 2009 1 次提交
  21. 16 3月, 2009 1 次提交
    • J
      Use f_lock to protect f_flags · db1dd4d3
      Jonathan Corbet 提交于
      Traditionally, changes to struct file->f_flags have been done under BKL
      protection, or with no protection at all.  This patch causes all f_flags
      changes after file open/creation time to be done under protection of
      f_lock.  This allows the removal of some BKL usage and fixes a number of
      longstanding (if microscopic) races.
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Cc: Al Viro <viro@ZenIV.linux.org.uk>
      Signed-off-by: NJonathan Corbet <corbet@lwn.net>
      db1dd4d3
  22. 11 2月, 2009 1 次提交
    • M
      Do not account for the address space used by hugetlbfs using VM_ACCOUNT · 5a6fe125
      Mel Gorman 提交于
      When overcommit is disabled, the core VM accounts for pages used by anonymous
      shared, private mappings and special mappings. It keeps track of VMAs that
      should be accounted for with VM_ACCOUNT and VMAs that never had a reserve
      with VM_NORESERVE.
      
      Overcommit for hugetlbfs is much riskier than overcommit for base pages
      due to contiguity requirements. It avoids overcommiting on both shared and
      private mappings using reservation counters that are checked and updated
      during mmap(). This ensures (within limits) that hugepages exist in the
      future when faults occurs or it is too easy to applications to be SIGKILLed.
      
      As hugetlbfs makes its own reservations of a different unit to the base page
      size, VM_ACCOUNT should never be set. Even if the units were correct, we would
      double account for the usage in the core VM and hugetlbfs. VM_NORESERVE may
      be set because an application can request no reserves be made for hugetlbfs
      at the risk of getting killed later.
      
      With commit fc8744ad, VM_NORESERVE and
      VM_ACCOUNT are getting unconditionally set for hugetlbfs-backed mappings. This
      breaks the accounting for both the core VM and hugetlbfs, can trigger an
      OOM storm when hugepage pools are too small lockups and corrupted counters
      otherwise are used. This patch brings hugetlbfs more in line with how the
      core VM treats VM_NORESERVE but prevents VM_ACCOUNT being set.
      Signed-off-by: NMel Gorman <mel@csn.ul.ie>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5a6fe125
  23. 06 2月, 2009 1 次提交
    • M
      Integrity: IMA file free imbalance · 1df9f0a7
      Mimi Zohar 提交于
      The number of calls to ima_path_check()/ima_file_free()
      should be balanced.  An extra call to fput(), indicates
      the file could have been accessed without first being
      measured.
      
      Although f_count is incremented/decremented in places other
      than fget/fput, like fget_light/fput_light and get_file, the
      current task must already hold a file refcnt.  The call to
      __fput() is delayed until the refcnt becomes 0, resulting
      in ima_file_free() flagging any changes.
      
      - add hook to increment opencount for IPC shared memory(SYSV),
        shmat files, and /dev/zero
      - moved NULL iint test in opencount_get()
      Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      1df9f0a7
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