1. 14 11月, 2008 3 次提交
  2. 14 10月, 2008 1 次提交
  3. 27 7月, 2008 1 次提交
  4. 25 7月, 2008 4 次提交
    • A
      hugetlbfs: per mount huge page sizes · a137e1cc
      Andi Kleen 提交于
      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
        superblock.
      - 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: NAdam Litke <agl@us.ibm.com>
      Acked-by: NNishanth Aravamudan <nacc@us.ibm.com>
      Signed-off-by: NAndi Kleen <ak@suse.de>
      Signed-off-by: NNick Piggin <npiggin@suse.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a137e1cc
    • A
      hugetlb: modular state for hugetlb page size · a5516438
      Andi Kleen 提交于
      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
      hstate.
      
      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: NAdam Litke <agl@us.ibm.com>
      Acked-by: NNishanth Aravamudan <nacc@us.ibm.com>
      Signed-off-by: NAndi Kleen <ak@suse.de>
      Signed-off-by: NNick Piggin <npiggin@suse.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a5516438
    • M
      hugetlb: guarantee that COW faults for a process that called mmap(MAP_PRIVATE)... · 04f2cbe3
      Mel Gorman 提交于
      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: NMel Gorman <mel@csn.ul.ie>
      Acked-by: NAdam 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      04f2cbe3
    • M
      hugetlb: reserve huge pages for reliable MAP_PRIVATE hugetlbfs mappings until fork() · a1e78772
      Mel Gorman 提交于
      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
      called.
      
      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: NMel Gorman <mel@csn.ul.ie>
      Acked-by: NAdam 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a1e78772
  5. 30 4月, 2008 1 次提交
  6. 28 4月, 2008 2 次提交
    • L
      mempolicy: use struct mempolicy pointer in shmem_sb_info · 71fe804b
      Lee Schermerhorn 提交于
      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: NLee 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      71fe804b
    • D
      mempolicy: support optional mode flags · 028fec41
      David Rientjes 提交于
      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
      unchanged.
      
      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: NDavid Rientjes <rientjes@google.com>
      Signed-off-by: NHugh Dickins <hugh@veritas.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      028fec41
  7. 19 3月, 2008 1 次提交
  8. 09 2月, 2008 1 次提交
  9. 06 2月, 2008 1 次提交
  10. 15 11月, 2007 2 次提交
    • A
      hugetlb: allow bulk updating in hugetlb_*_quota() · 9a119c05
      Adam Litke 提交于
      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: NAdam 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      9a119c05
    • A
      hugetlb: fix quota management for private mappings · c79fb75e
      Adam Litke 提交于
      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: NAdam 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c79fb75e
  11. 17 10月, 2007 7 次提交
  12. 31 8月, 2007 1 次提交
    • D
      hugepage: fix broken check for offset alignment in hugepage mappings · dec4ad86
      David Gibson 提交于
      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: NDavid 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      dec4ad86
  13. 20 7月, 2007 1 次提交
    • P
      mm: Remove slab destructors from kmem_cache_create(). · 20c2df83
      Paul Mundt 提交于
      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
      either.
      
      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: NPaul Mundt <lethal@linux-sh.org>
      20c2df83
  14. 17 7月, 2007 2 次提交
    • L
      hugetlbfs: handle empty options string · b4c07bce
      Lee Schermerhorn 提交于
      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:
      	hugetlbfs-use-lib-parser-fix-docs.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: NLee Schermerhorn <lee.schermerhorn@hp.com>
      Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b4c07bce
    • R
      hugetlbfs: use lib/parser, fix docs · e73a75fa
      Randy Dunlap 提交于
      Use lib/parser.c to parse hugetlbfs mount options.  Correct docs in
      hugetlbpage.txt.
      
      old size of hugetlbfs_fill_super:  675 bytes
      new size of hugetlbfs_fill_super:  686 bytes
      (hugetlbfs_parse_options() is inlined)
      Signed-off-by: NRandy 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: NWilliam Lee Irwin III <wli@holomorphy.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e73a75fa
  15. 17 6月, 2007 1 次提交
    • E
      shm: fix the filename of hugetlb sysv shared memory · 9d66586f
      Eric W. Biederman 提交于
      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: NEric 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      9d66586f
  16. 17 5月, 2007 1 次提交
    • C
      Remove SLAB_CTOR_CONSTRUCTOR · a35afb83
      Christoph Lameter 提交于
      SLAB_CTOR_CONSTRUCTOR is always specified. No point in checking it.
      Signed-off-by: NChristoph 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a35afb83
  17. 08 5月, 2007 5 次提交
  18. 13 2月, 2007 2 次提交
  19. 10 2月, 2007 1 次提交
    • K
      [PATCH] hugetlb: preserve hugetlb pte dirty state · 6649a386
      Ken Chen 提交于
      __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 >
      /proc/sys/vm/drop_caches".
      
      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
      application.
      
      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: NKen 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: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      6649a386
  20. 22 12月, 2006 1 次提交
    • L
      VM: Remove "clear_page_dirty()" and "test_clear_page_dirty()" functions · fba2591b
      Linus Torvalds 提交于
      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
      do.
      
      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: NLinus Torvalds <torvalds@osdl.org>
      fba2591b
  21. 09 12月, 2006 1 次提交