1. 05 Feb, 2008 1 commit
    • Christoph Lameter's avatar
      Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user · eebd2aa3
      Christoph Lameter authored
      Simplify page cache zeroing of segments of pages through 3 functions
      
      zero_user_segments(page, start1, end1, start2, end2)
      
              Zeros two segments of the page. It takes the position where to
              start and end the zeroing which avoids length calculations and
      	makes code clearer.
      
      zero_user_segment(page, start, end)
      
              Same for a single segment.
      
      zero_user(page, start, length)
      
              Length variant for the case where we know the length.
      
      We remove the zero_user_page macro. Issues:
      
      1. Its a macro. Inline functions are preferable.
      
      2. The KM_USER0 macro is only defined for HIGHMEM.
      
         Having to treat this special case everywhere makes the
         code needlessly complex. The parameter for zeroing is always
         KM_USER0 except in one single case that we open code.
      
      Avoiding KM_USER0 makes a lot of code not having to be dealing
      with the special casing for HIGHMEM anymore. Dealing with
      kmap is only necessary for HIGHMEM configurations. In those
      configurations we use KM_USER0 like we do for a series of other
      functions defined in highmem.h.
      
      Since KM_USER0 is depends on HIGHMEM the existing zero_user_page
      function could not be a macro. zero_user_* functions introduced
      here can be be inline because that constant is not used when these
      functions are called.
      
      Also extract the flushing of the caches to be outside of the kmap.
      
      [akpm@linux-foundation.org: fix nfs and ntfs build]
      [akpm@linux-foundation.org: fix ntfs build some more]
      Signed-off-by: default avatarChristoph Lameter <clameter@sgi.com>
      Cc: Steven French <sfrench@us.ibm.com>
      Cc: Michael Halcrow <mhalcrow@us.ibm.com>
      Cc: <linux-ext4@vger.kernel.org>
      Cc: Steven Whitehouse <swhiteho@redhat.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: David Chinner <dgc@sgi.com>
      Cc: Michael Halcrow <mhalcrow@us.ibm.com>
      Cc: Steven French <sfrench@us.ibm.com>
      Cc: Steven Whitehouse <swhiteho@redhat.com>
      Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      eebd2aa3
  2. 30 Jan, 2008 5 commits
  3. 06 Dec, 2007 1 commit
  4. 09 Oct, 2007 2 commits
  5. 19 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
      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: default avatarPaul Mundt <lethal@linux-sh.org>
      20c2df83
  6. 10 Jul, 2007 2 commits
  7. 14 May, 2007 1 commit
  8. 30 Apr, 2007 4 commits
  9. 03 Feb, 2007 2 commits
  10. 07 Dec, 2006 2 commits
  11. 06 Dec, 2006 5 commits
  12. 27 Sep, 2006 1 commit
  13. 22 Sep, 2006 2 commits
    • Trond Myklebust's avatar
      NFS: Make read() return an ESTALE if the file has been deleted · 5f004cf2
      Trond Myklebust authored
      Currently, a read() request will return EIO even if the file has been
      deleted on the server, simply because that is what the VM will return
      if the call to readpage() fails to update the page.
      
      Ensure that readpage() marks the inode as stale if it receives an ESTALE.
      Then return that error to userland.
      Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
      5f004cf2
    • David Howells's avatar
      NFS: Share NFS superblocks per-protocol per-server per-FSID · 54ceac45
      David Howells authored
      The attached patch makes NFS share superblocks between mounts from the same
      server and FSID over the same protocol.
      
      It does this by creating each superblock with a false root and returning the
      real root dentry in the vfsmount presented by get_sb(). The root dentry set
      starts off as an anonymous dentry if we don't already have the dentry for its
      inode, otherwise it simply returns the dentry we already have.
      
      We may thus end up with several trees of dentries in the superblock, and if at
      some later point one of anonymous tree roots is discovered by normal filesystem
      activity to be located in another tree within the superblock, the anonymous
      root is named and materialises attached to the second tree at the appropriate
      point.
      
      Why do it this way? Why not pass an extra argument to the mount() syscall to
      indicate the subpath and then pathwalk from the server root to the desired
      directory? You can't guarantee this will work for two reasons:
      
       (1) The root and intervening nodes may not be accessible to the client.
      
           With NFS2 and NFS3, for instance, mountd is called on the server to get
           the filehandle for the tip of a path. mountd won't give us handles for
           anything we don't have permission to access, and so we can't set up NFS
           inodes for such nodes, and so can't easily set up dentries (we'd have to
           have ghost inodes or something).
      
           With this patch we don't actually create dentries until we get handles
           from the server that we can use to set up their inodes, and we don't
           actually bind them into the tree until we know for sure where they go.
      
       (2) Inaccessible symbolic links.
      
           If we're asked to mount two exports from the server, eg:
      
      	mount warthog:/warthog/aaa/xxx /mmm
      	mount warthog:/warthog/bbb/yyy /nnn
      
           We may not be able to access anything nearer the root than xxx and yyy,
           but we may find out later that /mmm/www/yyy, say, is actually the same
           directory as the one mounted on /nnn. What we might then find out, for
           example, is that /warthog/bbb was actually a symbolic link to
           /warthog/aaa/xxx/www, but we can't actually determine that by talking to
           the server until /warthog is made available by NFS.
      
           This would lead to having constructed an errneous dentry tree which we
           can't easily fix. We can end up with a dentry marked as a directory when
           it should actually be a symlink, or we could end up with an apparently
           hardlinked directory.
      
           With this patch we need not make assumptions about the type of a dentry
           for which we can't retrieve information, nor need we assume we know its
           place in the grand scheme of things until we actually see that place.
      
      This patch reduces the possibility of aliasing in the inode and page caches for
      inodes that may be accessed by more than one NFS export. It also reduces the
      number of superblocks required for NFS where there are many NFS exports being
      used from a server (home directory server + autofs for example).
      
      This in turn makes it simpler to do local caching of network filesystems, as it
      can then be guaranteed that there won't be links from multiple inodes in
      separate superblocks to the same cache file.
      
      Obviously, cache aliasing between different levels of NFS protocol could still
      be a problem, but at least that gives us another key to use when indexing the
      cache.
      
      This patch makes the following changes:
      
       (1) The server record construction/destruction has been abstracted out into
           its own set of functions to make things easier to get right.  These have
           been moved into fs/nfs/client.c.
      
           All the code in fs/nfs/client.c has to do with the management of
           connections to servers, and doesn't touch superblocks in any way; the
           remaining code in fs/nfs/super.c has to do with VFS superblock management.
      
       (2) The sequence of events undertaken by NFS mount is now reordered:
      
           (a) A volume representation (struct nfs_server) is allocated.
      
           (b) A server representation (struct nfs_client) is acquired.  This may be
           	 allocated or shared, and is keyed on server address, port and NFS
           	 version.
      
           (c) If allocated, the client representation is initialised.  The state
           	 member variable of nfs_client is used to prevent a race during
           	 initialisation from two mounts.
      
           (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find
           	 the root filehandle for the mount (fs/nfs/getroot.c).  For NFS2/3 we
           	 are given the root FH in advance.
      
           (e) The volume FSID is probed for on the root FH.
      
           (f) The volume representation is initialised from the FSINFO record
           	 retrieved on the root FH.
      
           (g) sget() is called to acquire a superblock.  This may be allocated or
           	 shared, keyed on client pointer and FSID.
      
           (h) If allocated, the superblock is initialised.
      
           (i) If the superblock is shared, then the new nfs_server record is
           	 discarded.
      
           (j) The root dentry for this mount is looked up from the root FH.
      
           (k) The root dentry for this mount is assigned to the vfsmount.
      
       (3) nfs_readdir_lookup() creates dentries for each of the entries readdir()
           returns; this function now attaches disconnected trees from alternate
           roots that happen to be discovered attached to a directory being read (in
           the same way nfs_lookup() is made to do for lookup ops).
      
           The new d_materialise_unique() function is now used to do this, thus
           permitting the whole thing to be done under one set of locks, and thus
           avoiding any race between mount and lookup operations on the same
           directory.
      
       (4) The client management code uses a new debug facility: NFSDBG_CLIENT which
           is set by echoing 1024 to /proc/net/sunrpc/nfs_debug.
      
       (5) Clone mounts are now called xdev mounts.
      
       (6) Use the dentry passed to the statfs() op as the handle for retrieving fs
           statistics rather than the root dentry of the superblock (which is now a
           dummy).
      Signed-Off-By: default avatarDavid Howells <dhowells@redhat.com>
      Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
      54ceac45
  14. 19 Sep, 2006 1 commit
  15. 08 Sep, 2006 1 commit
  16. 24 Aug, 2006 1 commit
    • Trond Myklebust's avatar
      NFS: Fix issue with EIO on NFS read · 79558f36
      Trond Myklebust authored
      The problem is that we may be caching writes that would extend the file and
      create a hole in the region that we are reading. In this case, we need to
      detect the eof from the server, ensure that we zero out the pages that
      are part of the hole and mark them as up to date.
      Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
      (cherry picked from 856b603b01b99146918c093969b6cb1b1b0f1c01 commit)
      79558f36
  17. 03 Aug, 2006 1 commit
  18. 30 Jun, 2006 1 commit
  19. 27 Jun, 2006 1 commit
  20. 09 Jun, 2006 3 commits
    • David Howells's avatar
      NFS: Split fs/nfs/inode.c · f7b422b1
      David Howells authored
      As fs/nfs/inode.c is rather large, heterogenous and unwieldy, the attached
      patch splits it up into a number of files:
      
       (*) fs/nfs/inode.c
      
           Strictly inode specific functions.
      
       (*) fs/nfs/super.c
      
           Superblock management functions for NFS and NFS4, normal access, clones
           and referrals.  The NFS4 superblock functions _could_ move out into a
           separate conditionally compiled file, but it's probably not worth it as
           there're so many common bits.
      
       (*) fs/nfs/namespace.c
      
           Some namespace-specific functions have been moved here.
      
       (*) fs/nfs/nfs4namespace.c
      
           NFS4-specific namespace functions (this could be merged into the previous
           file).  This file is conditionally compiled.
      
       (*) fs/nfs/internal.h
      
           Inter-file declarations, plus a few simple utility functions moved from
           fs/nfs/inode.c.
      
           Additionally, all the in-.c-file externs have been moved here, and those
           files they were moved from now includes this file.
      
      For the most part, the functions have not been changed, only some multiplexor
      functions have changed significantly.
      
      I've also:
      
       (*) Added some extra banner comments above some functions.
      
       (*) Rearranged the function order within the files to be more logical and
           better grouped (IMO), though someone may prefer a different order.
      
       (*) Reduced the number of #ifdefs in .c files.
      
       (*) Added missing __init and __exit directives.
      Signed-Off-By: default avatarDavid Howells <dhowells@redhat.com>
      f7b422b1
    • Chuck Lever's avatar
      NFS: Optimize allocation of nfs_read/write_data structures · 0d0b5cb3
      Chuck Lever authored
      Clean up use of page_array, and fix an off-by-one error noticed by Tom
      Talpey which causes kmalloc calls in cases where using the page_array
      is sufficient.
      
      Test plan:
      Normal client functional testing with r/wsize=32768.
      Signed-off-by: default avatarChuck Lever <cel@netapp.com>
      Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
      0d0b5cb3
    • Trond Myklebust's avatar
      NFS: Clean up and fix page zeroing when we have short reads · 1de3fc12
      Trond Myklebust authored
      The code that is supposed to zero the uninitialised partial pages when the
      server returns a short read is currently broken: it looks at the nfs_page
      wb_pgbase and wb_bytes fields instead of the equivalent nfs_read_data
      values when deciding where to start truncating the page.
      
      Also ensure that we are more careful about setting PG_uptodate
      before retrying a short read: the retry will change the nfs_read_data
      args.pgbase and args.count.
      Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
      1de3fc12
  21. 26 Mar, 2006 1 commit
  22. 20 Mar, 2006 1 commit