1. 13 Oct, 2008 1 commit
  2. 26 Jul, 2008 1 commit
  3. 24 Jul, 2008 4 commits
    • Andi Kleen's avatar
      hugetlbfs: per mount huge page sizes · a137e1cc
      Andi Kleen authored
      Add the ability to configure the hugetlb hstate used on a per mount basis.
      - Add a new pagesize= option to the hugetlbfs mount that allows setting
        the page size
      - This option causes the mount code to find the hstate corresponding to the
        specified size, and sets up a pointer to the hstate in the mount's
      - Change the hstate accessors to use this information rather than the
        global_hstate they were using (requires a slight change in mm/memory.c
        so we don't NULL deref in the error-unmap path -- see comments).
      [np: take hstate out of hugetlbfs inode and vma->vm_private_data]
      Acked-by: default avatarAdam Litke <agl@us.ibm.com>
      Acked-by: default avatarNishanth Aravamudan <nacc@us.ibm.com>
      Signed-off-by: default avatarAndi Kleen <ak@suse.de>
      Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Andi Kleen's avatar
      hugetlb: modular state for hugetlb page size · a5516438
      Andi Kleen authored
      The goal of this patchset is to support multiple hugetlb page sizes.  This
      is achieved by introducing a new struct hstate structure, which
      encapsulates the important hugetlb state and constants (eg.  huge page
      size, number of huge pages currently allocated, etc).
      The hstate structure is then passed around the code which requires these
      fields, they will do the right thing regardless of the exact hstate they
      are operating on.
      This patch adds the hstate structure, with a single global instance of it
      (default_hstate), and does the basic work of converting hugetlb to use the
      Future patches will add more hstate structures to allow for different
      hugetlbfs mounts to have different page sizes.
      [akpm@linux-foundation.org: coding-style fixes]
      Acked-by: default avatarAdam Litke <agl@us.ibm.com>
      Acked-by: default avatarNishanth Aravamudan <nacc@us.ibm.com>
      Signed-off-by: default avatarAndi Kleen <ak@suse.de>
      Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Mel Gorman's avatar
      hugetlb: guarantee that COW faults for a process that called mmap(MAP_PRIVATE)... · 04f2cbe3
      Mel Gorman authored
      hugetlb: guarantee that COW faults for a process that called mmap(MAP_PRIVATE) on hugetlbfs will succeed
      After patch 2 in this series, a process that successfully calls mmap() for
      a MAP_PRIVATE mapping will be guaranteed to successfully fault until a
      process calls fork().  At that point, the next write fault from the parent
      could fail due to COW if the child still has a reference.
      We only reserve pages for the parent but a copy must be made to avoid
      leaking data from the parent to the child after fork().  Reserves could be
      taken for both parent and child at fork time to guarantee faults but if
      the mapping is large it is highly likely we will not have sufficient pages
      for the reservation, and it is common to fork only to exec() immediatly
      after.  A failure here would be very undesirable.
      Note that the current behaviour of mainline with MAP_PRIVATE pages is
      pretty bad.  The following situation is allowed to occur today.
      1. Process calls mmap(MAP_PRIVATE)
      2. Process calls mlock() to fault all pages and makes sure it succeeds
      3. Process forks()
      4. Process writes to MAP_PRIVATE mapping while child still exists
      5. If the COW fails at this point, the process gets SIGKILLed even though it
         had taken care to ensure the pages existed
      This patch improves the situation by guaranteeing the reliability of the
      process that successfully calls mmap().  When the parent performs COW, it
      will try to satisfy the allocation without using reserves.  If that fails
      the parent will steal the page leaving any children without a page.
      Faults from the child after that point will result in failure.  If the
      child COW happens first, an attempt will be made to allocate the page
      without reserves and the child will get SIGKILLed on failure.
      To summarise the new behaviour:
      1. If the original mapper performs COW on a private mapping with multiple
         references, it will attempt to allocate a hugepage from the pool or
         the buddy allocator without using the existing reserves. On fail, VMAs
         mapping the same area are traversed and the page being COW'd is unmapped
         where found. It will then steal the original page as the last mapper in
         the normal way.
      2. The VMAs the pages were unmapped from are flagged to note that pages
         with data no longer exist. Future no-page faults on those VMAs will
         terminate the process as otherwise it would appear that data was corrupted.
         A warning is printed to the console that this situation occured.
      2. If the child performs COW first, it will attempt to satisfy the COW
         from the pool if there are enough pages or via the buddy allocator if
         overcommit is allowed and the buddy allocator can satisfy the request. If
         it fails, the child will be killed.
      If the pool is large enough, existing applications will not notice that
      the reserves were a factor.  Existing applications depending on the
      no-reserves been set are unlikely to exist as for much of the history of
      hugetlbfs, pages were prefaulted at mmap(), allocating the pages at that
      point or failing the mmap().
      [npiggin@suse.de: fix CONFIG_HUGETLB=n build]
      Signed-off-by: default avatarMel Gorman <mel@csn.ul.ie>
      Acked-by: default avatarAdam Litke <agl@us.ibm.com>
      Cc: Andy Whitcroft <apw@shadowen.org>
      Cc: William Lee Irwin III <wli@holomorphy.com>
      Cc: Hugh Dickins <hugh@veritas.com>
      Cc: Nick Piggin <npiggin@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Mel Gorman's avatar
      hugetlb: reserve huge pages for reliable MAP_PRIVATE hugetlbfs mappings until fork() · a1e78772
      Mel Gorman authored
      This patch reserves huge pages at mmap() time for MAP_PRIVATE mappings in
      a similar manner to the reservations taken for MAP_SHARED mappings.  The
      reserve count is accounted both globally and on a per-VMA basis for
      private mappings.  This guarantees that a process that successfully calls
      mmap() will successfully fault all pages in the future unless fork() is
      The characteristics of private mappings of hugetlbfs files behaviour after
      this patch are;
      1. The process calling mmap() is guaranteed to succeed all future faults until
         it forks().
      2. On fork(), the parent may die due to SIGKILL on writes to the private
         mapping if enough pages are not available for the COW. For reasonably
         reliable behaviour in the face of a small huge page pool, children of
         hugepage-aware processes should not reference the mappings; such as
         might occur when fork()ing to exec().
      3. On fork(), the child VMAs inherit no reserves. Reads on pages already
         faulted by the parent will succeed. Successful writes will depend on enough
         huge pages being free in the pool.
      4. Quotas of the hugetlbfs mount are checked at reserve time for the mapper
         and at fault time otherwise.
      Before this patch, all reads or writes in the child potentially needs page
      allocations that can later lead to the death of the parent.  This applies
      to reads and writes of uninstantiated pages as well as COW.  After the
      patch it is only a write to an instantiated page that causes problems.
      Signed-off-by: default avatarMel Gorman <mel@csn.ul.ie>
      Acked-by: default avatarAdam Litke <agl@us.ibm.com>
      Cc: Andy Whitcroft <apw@shadowen.org>
      Cc: William Lee Irwin III <wli@holomorphy.com>
      Cc: Hugh Dickins <hugh@veritas.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  4. 30 Apr, 2008 1 commit
  5. 28 Apr, 2008 2 commits
    • Lee Schermerhorn's avatar
      mempolicy: use struct mempolicy pointer in shmem_sb_info · 71fe804b
      Lee Schermerhorn authored
      This patch replaces the mempolicy mode, mode_flags, and nodemask in the
      shmem_sb_info struct with a struct mempolicy pointer, initialized to NULL.
      This removes dependency on the details of mempolicy from shmem.c and hugetlbfs
      inode.c and simplifies the interfaces.
      mpol_parse_str() in mempolicy.c is changed to return, via a pointer to a
      pointer arg, a struct mempolicy pointer on success.  For MPOL_DEFAULT, the
      returned pointer is NULL.  Further, mpol_parse_str() now takes a 'no_context'
      argument that causes the input nodemask to be stored in the w.user_nodemask of
      the created mempolicy for use when the mempolicy is installed in a tmpfs inode
      shared policy tree.  At that time, any cpuset contextualization is applied to
      the original input nodemask.  This preserves the previous behavior where the
      input nodemask was stored in the superblock.  We can think of the returned
      mempolicy as "context free".
      Because mpol_parse_str() is now calling mpol_new(), we can remove from
      mpol_to_str() the semantic checks that mpol_new() already performs.
      Add 'no_context' parameter to mpol_to_str() to specify that it should format
      the nodemask in w.user_nodemask for 'bind' and 'interleave' policies.
      Change mpol_shared_policy_init() to take a pointer to a "context free" struct
      mempolicy and to create a new, "contextualized" mempolicy using the mode,
      mode_flags and user_nodemask from the input mempolicy.
        Note: we know that the mempolicy passed to mpol_to_str() or
        mpol_shared_policy_init() from a tmpfs superblock is "context free".  This
        is currently the only instance thereof.  However, if we found more uses for
        this concept, and introduced any ambiguity as to whether a mempolicy was
        context free or not, we could add another internal mode flag to identify
        context free mempolicies.  Then, we could remove the 'no_context' argument
        from mpol_to_str().
      Added shmem_get_sbmpol() to return a reference counted superblock mempolicy,
      if one exists, to pass to mpol_shared_policy_init().  We must add the
      reference under the sb stat_lock to prevent races with replacement of the mpol
      by remount.  This reference is removed in mpol_shared_policy_init().
      [akpm@linux-foundation.org: build fix]
      [akpm@linux-foundation.org: another build fix]
      [akpm@linux-foundation.org: yet another build fix]
      Signed-off-by: default avatarLee Schermerhorn <lee.schermerhorn@hp.com>
      Cc: Christoph Lameter <clameter@sgi.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Andi Kleen <ak@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • David Rientjes's avatar
      mempolicy: support optional mode flags · 028fec41
      David Rientjes authored
      With the evolution of mempolicies, it is necessary to support mempolicy mode
      flags that specify how the policy shall behave in certain circumstances.  The
      most immediate need for mode flag support is to suppress remapping the
      nodemask of a policy at the time of rebind.
      Both the mempolicy mode and flags are passed by the user in the 'int policy'
      formal of either the set_mempolicy() or mbind() syscall.  A new constant,
      MPOL_MODE_FLAGS, represents the union of legal optional flags that may be
      passed as part of this int.  Mempolicies that include illegal flags as part of
      their policy are rejected as invalid.
      An additional member to struct mempolicy is added to support the mode flags:
      	struct mempolicy {
      		unsigned short policy;
      		unsigned short flags;
      The splitting of the 'int' actual passed by the user is done in
      sys_set_mempolicy() and sys_mbind() for their respective syscalls.  This is
      done by intersecting the actual with MPOL_MODE_FLAGS, rejecting the syscall of
      there are additional flags, and storing it in the new 'flags' member of struct
      mempolicy.  The intersection of the actual with ~MPOL_MODE_FLAGS is stored in
      the 'policy' member of the struct and all current users of pol->policy remain
      The union of the policy mode and optional mode flags is passed back to the
      user in get_mempolicy().
      This combination of mode and flags within the same actual does not break
      userspace code that relies on get_mempolicy(&policy, ...) and either
      	switch (policy) {
      	case MPOL_BIND:
      	case MPOL_INTERLEAVE:
      statements or
      	if (policy == MPOL_INTERLEAVE) {
      statements.  Such applications would need to use optional mode flags when
      calling set_mempolicy() or mbind() for these previously implemented statements
      to stop working.  If an application does start using optional mode flags, it
      will need to mask the optional flags off the policy in switch and conditional
      statements that only test mode.
      An additional member is also added to struct shmem_sb_info to store the
      optional mode flags.
      [hugh@veritas.com: shmem mpol: fix build warning]
      Cc: Paul Jackson <pj@sgi.com>
      Cc: Christoph Lameter <clameter@sgi.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      Cc: Andi Kleen <ak@suse.de>
      Signed-off-by: default avatarDavid Rientjes <rientjes@google.com>
      Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  6. 19 Mar, 2008 1 commit
  7. 08 Feb, 2008 1 commit
  8. 05 Feb, 2008 1 commit
  9. 15 Nov, 2007 2 commits
    • Adam Litke's avatar
      hugetlb: allow bulk updating in hugetlb_*_quota() · 9a119c05
      Adam Litke authored
      Add a second parameter 'delta' to hugetlb_get_quota and hugetlb_put_quota to
      allow bulk updating of the sbinfo->free_blocks counter.  This will be used by
      the next patch in the series.
      Signed-off-by: default avatarAdam Litke <agl@us.ibm.com>
      Cc: Ken Chen <kenchen@google.com>
      Cc: Andy Whitcroft <apw@shadowen.org>
      Cc: Dave Hansen <haveblue@us.ibm.com>
      Cc: David Gibson <hermes@gibson.dropbear.id.au>
      Cc: William Lee Irwin III <wli@holomorphy.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Adam Litke's avatar
      hugetlb: fix quota management for private mappings · c79fb75e
      Adam Litke authored
      The hugetlbfs quota management system was never taught to handle MAP_PRIVATE
      mappings when that support was added.  Currently, quota is debited at page
      instantiation and credited at file truncation.  This approach works correctly
      for shared pages but is incomplete for private pages.  In addition to
      hugetlb_no_page(), private pages can be instantiated by hugetlb_cow(); but
      this function does not respect quotas.
      Private huge pages are treated very much like normal, anonymous pages.  They
      are not "backed" by the hugetlbfs file and are not stored in the mapping's
      radix tree.  This means that private pages are invisible to
      truncate_hugepages() so that function will not credit the quota.
      This patch (based on a prototype provided by Ken Chen) moves quota crediting
      for all pages into free_huge_page().  page->private is used to store a pointer
      to the mapping to which this page belongs.  This is used to credit quota on
      the appropriate hugetlbfs instance.
      Signed-off-by: default avatarAdam Litke <agl@us.ibm.com>
      Cc: Ken Chen <kenchen@google.com>
      Cc: Ken Chen <kenchen@google.com>
      Cc: Andy Whitcroft <apw@shadowen.org>
      Cc: Dave Hansen <haveblue@us.ibm.com>
      Cc: David Gibson <hermes@gibson.dropbear.id.au>
      Cc: William Lee Irwin III <wli@holomorphy.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  10. 17 Oct, 2007 4 commits
    • Dave Hansen's avatar
      r/o bind mounts: filesystem helpers for custom 'struct file's · ce8d2cdf
      Dave Hansen authored
      Why do we need r/o bind mounts?
      This feature allows a read-only view into a read-write filesystem.  In the
      process of doing that, it also provides infrastructure for keeping track of
      the number of writers to any given mount.
      This has a number of uses.  It allows chroots to have parts of filesystems
      writable.  It will be useful for containers in the future because users may
      have root inside a container, but should not be allowed to write to
      somefilesystems.  This also replaces patches that vserver has had out of the
      tree for several years.
      It allows security enhancement by making sure that parts of your filesystem
      read-only (such as when you don't trust your FTP server), when you don't want
      to have entire new filesystems mounted, or when you want atime selectively
      updated.  I've been using the following script to test that the feature is
      working as desired.  It takes a directory and makes a regular bind and a r/o
      bind mount of it.  It then performs some normal filesystem operations on the
      three directories, including ones that are expected to fail, like creating a
      file on the r/o mount.
      This patch:
      Some filesystems forego the vfs and may_open() and create their own 'struct
      This patch creates a couple of helper functions which can be used by these
      filesystems, and will provide a unified place which the r/o bind mount code
      may patch.
      Also, rename an existing, static-scope init_file() to a less generic name.
      Signed-off-by: default avatarDave Hansen <haveblue@us.ibm.com>
      Cc: Christoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Joern Engel's avatar
      introduce I_SYNC · 1c0eeaf5
      Joern Engel authored
      I_LOCK was used for several unrelated purposes, which caused deadlock
      situations in certain filesystems as a side effect.  One of the purposes
      now uses the new I_SYNC bit.
      Also document the various bits and change their order from historical to
      [bunk@stusta.de: make fs/inode.c:wake_up_inode() static]
      Signed-off-by: default avatarJoern Engel <joern@wohnheim.fh-wedel.de>
      Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
      Cc: David Chinner <dgc@sgi.com>
      Cc: Anton Altaparmakov <aia21@cam.ac.uk>
      Cc: Al Viro <viro@ftp.linux.org.uk>
      Cc: Christoph Hellwig <hch@infradead.org>
      Signed-off-by: default avatarAdrian Bunk <bunk@stusta.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Christoph Lameter's avatar
      Slab API: remove useless ctor parameter and reorder parameters · 4ba9b9d0
      Christoph Lameter authored
      Slab constructors currently have a flags parameter that is never used.  And
      the order of the arguments is opposite to other slab functions.  The object
      pointer is placed before the kmem_cache pointer.
              ctor(void *object, struct kmem_cache *s, unsigned long flags)
              ctor(struct kmem_cache *s, void *object)
      throughout the kernel
      [akpm@linux-foundation.org: coupla fixes]
      Signed-off-by: default avatarChristoph Lameter <clameter@sgi.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Peter Zijlstra's avatar
      mm: bdi init hooks · e0bf68dd
      Peter Zijlstra authored
      provide BDI constructor/destructor hooks
      [akpm@linux-foundation.org: compile fix]
      Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  11. 16 Oct, 2007 3 commits
  12. 31 Aug, 2007 1 commit
    • David Gibson's avatar
      hugepage: fix broken check for offset alignment in hugepage mappings · dec4ad86
      David Gibson authored
      For hugepage mappings, the file offset, like the address and size, needs to
      be aligned to the size of a hugepage.
      In commit 68589bc3, the check for this was
      moved into prepare_hugepage_range() along with the address and size checks.
       But since BenH's rework of the get_unmapped_area() paths leading up to
      commit 4b1d8929, prepare_hugepage_range()
      is only called for MAP_FIXED mappings, not for other mappings.  This means
      we're no longer ever checking for an aligned offset - I've confirmed that
      mmap() will (apparently) succeed with a misaligned offset on both powerpc
      and i386 at least.
      This patch restores the check, removing it from prepare_hugepage_range()
      and putting it back into hugetlbfs_file_mmap().  I'm putting it there,
      rather than in the get_unmapped_area() path so it only needs to go in one
      place, than separately in the half-dozen or so arch-specific
      implementations of hugetlb_get_unmapped_area().
      Signed-off-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
      Cc: Adam Litke <agl@us.ibm.com>
      Cc: Andi Kleen <ak@suse.de>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  13. 20 Jul, 2007 1 commit
    • Paul Mundt's avatar
      mm: Remove slab destructors from kmem_cache_create(). · 20c2df83
      Paul Mundt authored
      Slab destructors were no longer supported after Christoph's
      c59def9f change. They've been
      BUGs for both slab and slub, and slob never supported them
      This rips out support for the dtor pointer from kmem_cache_create()
      completely and fixes up every single callsite in the kernel (there were
      about 224, not including the slab allocator definitions themselves,
      or the documentation references).
      Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
  14. 16 Jul, 2007 2 commits
    • Lee Schermerhorn's avatar
      hugetlbfs: handle empty options string · b4c07bce
      Lee Schermerhorn authored
      I was seeing a null pointer deref in fs/super.c:vfs_kern_mount().
      Some file system get_sb() handler was returning NULL mnt_sb with
      a non-negative return value.  I also noticed a "hugetlbfs: Bad
      mount option:" message in the log.
      Turns out that hugetlbfs_parse_options() was not checking for an
      empty option string after call to strsep().  On failure,
      hugetlbfs_parse_options() returns 1.  hugetlbfs_fill_super() just
      passed this return code back up the call stack where
      vfs_kern_mount() missed the error and proceeded with a NULL mnt_sb.
      Apparently introduced by patch:
      The problem was exposed by this line in my fstab:
      none        /huge       hugetlbfs   defaults    0 0
      It can also be demonstrated by invoking mount of hugetlbfs
      directly with no options or a bogus option.
      This patch:
      1) adds the check for empty option to hugetlbfs_parse_options(),
      2) enhances the error message to bracket any unrecognized
         option with quotes ,
      3) modifies hugetlbfs_parse_options() to return -EINVAL on any
         unrecognized option,
      4) adds a BUG_ON() to vfs_kern_mount() to catch any get_sb()
         handler that returns a NULL mnt->mnt_sb with a return value
         >= 0.
      Signed-off-by: default avatarLee Schermerhorn <lee.schermerhorn@hp.com>
      Acked-by: default avatarRandy Dunlap <randy.dunlap@oracle.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Randy Dunlap's avatar
      hugetlbfs: use lib/parser, fix docs · e73a75fa
      Randy Dunlap authored
      Use lib/parser.c to parse hugetlbfs mount options.  Correct docs in
      old size of hugetlbfs_fill_super:  675 bytes
      new size of hugetlbfs_fill_super:  686 bytes
      (hugetlbfs_parse_options() is inlined)
      Signed-off-by: default avatarRandy Dunlap <randy.dunlap@oracle.com>
      Cc: Hugh Dickins <hugh@veritas.com>
      Cc: David Gibson <david@gibson.dropbear.id.au>
      Cc: Adam Litke <agl@us.ibm.com>
      Acked-by: default avatarWilliam Lee Irwin III <wli@holomorphy.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  15. 16 Jun, 2007 1 commit
    • Eric W. Biederman's avatar
      shm: fix the filename of hugetlb sysv shared memory · 9d66586f
      Eric W. Biederman authored
      Some user space tools need to identify SYSV shared memory when examining
      /proc/<pid>/maps.  To do so they look for a block device with major zero, a
      dentry named SYSV<sysv key>, and having the minor of the internal sysv
      shared memory kernel mount.
      To help these tools and to make it easier for people just browsing
      /proc/<pid>/maps this patch modifies hugetlb sysv shared memory to use the
      SYSV<key> dentry naming convention.
      User space tools will still have to be aware that hugetlb sysv shared
      memory lives on a different internal kernel mount and so has a different
      block device minor number from the rest of sysv shared memory.
      Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
      Cc: "Serge E. Hallyn" <serge@hallyn.com>
      Cc: Albert Cahalan <acahalan@gmail.com>
      Cc: Badari Pulavarty <pbadari@us.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  16. 17 May, 2007 1 commit
    • Christoph Lameter's avatar
      Remove SLAB_CTOR_CONSTRUCTOR · a35afb83
      Christoph Lameter authored
      SLAB_CTOR_CONSTRUCTOR is always specified. No point in checking it.
      Signed-off-by: default avatarChristoph Lameter <clameter@sgi.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Jens Axboe <jens.axboe@oracle.com>
      Cc: Steven French <sfrench@us.ibm.com>
      Cc: Michael Halcrow <mhalcrow@us.ibm.com>
      Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
      Cc: Miklos Szeredi <miklos@szeredi.hu>
      Cc: Steven Whitehouse <swhiteho@redhat.com>
      Cc: Roman Zippel <zippel@linux-m68k.org>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Dave Kleikamp <shaggy@austin.ibm.com>
      Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
      Cc: "J. Bruce Fields" <bfields@fieldses.org>
      Cc: Anton Altaparmakov <aia21@cantab.net>
      Cc: Mark Fasheh <mark.fasheh@oracle.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Jan Kara <jack@ucw.cz>
      Cc: David Chinner <dgc@sgi.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  17. 07 May, 2007 5 commits
  18. 12 Feb, 2007 2 commits
  19. 09 Feb, 2007 1 commit
    • Ken Chen's avatar
      [PATCH] hugetlb: preserve hugetlb pte dirty state · 6649a386
      Ken Chen authored
      __unmap_hugepage_range() is buggy that it does not preserve dirty state of
      huge_pte when unmapping hugepage range.  It causes data corruption in the
      event of dop_caches being used by sys admin.  For example, an application
      creates a hugetlb file, modify pages, then unmap it.  While leaving the
      hugetlb file alive, comes along sys admin doing a "echo 3 >
      drop_pagecache_sb() will happily free all pages that aren't marked dirty if
      there are no active mapping.  Later when application remaps the hugetlb
      file back and all data are gone, triggering catastrophic flip over on
      Not only that, the internal resv_huge_pages count will also get all messed
      up.  Fix it up by marking page dirty appropriately.
      Signed-off-by: default avatarKen Chen <kenchen@google.com>
      Cc: "Nish Aravamudan" <nish.aravamudan@gmail.com>
      Cc: Adam Litke <agl@us.ibm.com>
      Cc: David Gibson <david@gibson.dropbear.id.au>
      Cc: William Lee Irwin III <wli@holomorphy.com>
      Cc: <stable@kernel.org>
      Cc: Hugh Dickins <hugh@veritas.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  20. 21 Dec, 2006 1 commit
    • Linus Torvalds's avatar
      VM: Remove "clear_page_dirty()" and "test_clear_page_dirty()" functions · fba2591b
      Linus Torvalds authored
      They were horribly easy to mis-use because of their tempting naming, and
      they also did way more than any users of them generally wanted them to
      A dirty page can become clean under two circumstances:
       (a) when we write it out.  We have "clear_page_dirty_for_io()" for
           this, and that function remains unchanged.
           In the "for IO" case it is not sufficient to just clear the dirty
           bit, you also have to mark the page as being under writeback etc.
       (b) when we actually remove a page due to it becoming inaccessible to
           users, notably because it was truncate()'d away or the file (or
           metadata) no longer exists, and we thus want to cancel any
           outstanding dirty state.
      For the (b) case, we now introduce "cancel_dirty_page()", which only
      touches the page state itself, and verifies that the page is not mapped
      (since cancelling writes on a mapped page would be actively wrong as it
      is still accessible to users).
      Some filesystems need to be fixed up for this: CIFS, FUSE, JFS,
      ReiserFS, XFS all use the old confusing functions, and will be fixed
      separately in subsequent commits (with some of them just removing the
      offending logic, and others using clear_page_dirty_for_io()).
      This was confirmed by Martin Michlmayr to fix the apt database
      corruption on ARM.
      Cc: Martin Michlmayr <tbm@cyrius.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Hugh Dickins <hugh@veritas.com>
      Cc: Nick Piggin <nickpiggin@yahoo.com.au>
      Cc: Arjan van de Ven <arjan@infradead.org>
      Cc: Andrei Popa <andrei.popa@i-neo.ro>
      Cc: Andrew Morton <akpm@osdl.org>
      Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
      Cc: Gordon Farquharson <gordonfarquharson@gmail.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
  21. 08 Dec, 2006 1 commit
  22. 07 Dec, 2006 2 commits
  23. 14 Nov, 2006 1 commit
    • Hugh Dickins's avatar
      [PATCH] hugetlb: prepare_hugepage_range check offset too · 68589bc3
      Hugh Dickins authored
      If hugetlbfs_file_mmap() returns a failure to do_mmap_pgoff() - for example,
      because the given file offset is not hugepage aligned - then do_mmap_pgoff
      will go to the unmap_and_free_vma backout path.
      But at this stage the vma hasn't been marked as hugepage, and the backout path
      will call unmap_region() on it.  That will eventually call down to the
      non-hugepage version of unmap_page_range().  On ppc64, at least, that will
      cause serious problems if there are any existing hugepage pagetable entries in
      the vicinity - for example if there are any other hugepage mappings under the
      same PUD.  unmap_page_range() will trigger a bad_pud() on the hugepage pud
      entries.  I suspect this will also cause bad problems on ia64, though I don't
      have a machine to test it on.
      prepare_hugepage_range() should check file offset alignment when it checks
      virtual address and length, to stop MAP_FIXED with a bad huge offset from
      unmapping before it fails further down.  PowerPC should apply the same
      prepare_hugepage_range alignment checks as ia64 and all the others do.
      Then none of the alignment checks in hugetlbfs_file_mmap are required (nor
      is the check for too small a mapping); but even so, move up setting of
      VM_HUGETLB and add a comment to warn of what David Gibson discovered - if
      hugetlbfs_file_mmap fails before setting it, do_mmap_pgoff's unmap_region
      when unwinding from error will go the non-huge way, which may cause bad
      behaviour on architectures (powerpc and ia64) which segregate their huge
      mappings into a separate region of the address space.
      Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Acked-by: default avatarAdam Litke <agl@us.ibm.com>
      Acked-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>