Eric Lee / smarc-fsl-linux-kernel

25 Mar, 2011

1 commit

23 Mar, 2011

1 commit

  • 4667058b7   nfs4: Fix NULL dereference at d_alloc_and_lookup() ... Browse Code »

    d_alloc_and_lookup() calls i_op->lookup method due to
    rootfh changes his fsid.

    During mount i_op of NFS root inode is set to
    nfs_mountpoint_inode_operations, if rpc_ops->getroot()
    and rpc_ops->getattr() return different fsid.

    After that nfs_follow_remote_path() raised oops:

    BUG: unable to handle kernel NULL pointer dereference at (null)
    IP: [< (null)>] (null)

    stack trace:

    d_alloc_and_lookup+0x4c/0x74
    do_lookup+0x1e3/0x280
    link_path_walk+0x12e/0xab0
    nfs4_remote_get_sb+0x56/0x2c0 [nfs]
    path_walk+0x67/0xe0
    vfs_path_lookup+0x8e/0x100
    nfs_follow_remote_path+0x16f/0x3e0 [nfs]
    nfs4_try_mount+0x6f/0xd0 [nfs]
    nfs_get_sb+0x269/0x400 [nfs]
    vfs_kern_mount+0x8a/0x1f0
    do_kern_mount+0x52/0x130
    do_mount+0x20a/0x260
    sys_mount+0x90/0xe0
    system_call_fastpath+0x16/0x1b

    So just refresh fsid, as RFC3530 doesn't specify behavior
    in case of rootfh changes fsid.

    Signed-off-by: Vitaliy Gusev
    Signed-off-by: Trond Myklebust

    Gusev Vitaliy
     

17 Mar, 2011

2 commits

  • b1942c5f8   nfs: store devname at disconnected NFS roots ... Browse Code »

    part 2: make sure that disconnected roots have corresponding mnt_devname
    values stashed into them.

    Have nfs*_get_root() stuff a copy of devname into ->d_fsdata of the
    found root, provided that it is disconnected.

    Have ->d_release() free it when dentry goes away.

    Have the places where NFS uses ->d_fsdata for sillyrename (and that
    can *never* happen to a disconnected root - dentry will be attached
    to its parent) free old devname copies if they find those.

    Signed-off-by: Al Viro

    Al Viro
     
  • 0d5839ad0   nfs: propagate devname to nfs{,4}_get_root() ... Browse Code »

    step 1 of ->mnt_devname fixes: make sure we have the value of devname
    available in ..._get_root().

    Signed-off-by: Al Viro

    Al Viro
     

13 Jan, 2011

1 commit

07 Jan, 2011

4 commits

  • 873feea09   fs: dcache per-inode inode alias locking ... Browse Code »

    dcache_inode_lock can be replaced with per-inode locking. Use existing
    inode->i_lock for this. This is slightly non-trivial because we sometimes
    need to find the inode from the dentry, which requires d_inode to be
    stabilised (either with refcount or d_lock).

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • fb045adb9   fs: dcache reduce branches in lookup path ... Browse Code »

    Reduce some branches and memory accesses in dcache lookup by adding dentry
    flags to indicate common d_ops are set, rather than having to check them.
    This saves a pointer memory access (dentry->d_op) in common path lookup
    situations, and saves another pointer load and branch in cases where we
    have d_op but not the particular operation.

    Patched with:

    git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • b5c84bf6f   fs: dcache remove dcache_lock ... Browse Code »

    dcache_lock no longer protects anything. remove it.

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • b23fb0a60   fs: scale inode alias list ... Browse Code »

    Add a new lock, dcache_inode_lock, to protect the inode's i_dentry list
    from concurrent modification. d_alias is also protected by d_lock.

    Signed-off-by: Nick Piggin

    Nick Piggin
     

26 Oct, 2010

1 commit

23 Jun, 2010

1 commit

15 May, 2010

2 commits

09 Jul, 2009

1 commit

  • b43f3cbd2   headers: mnt_namespace.h redux ... Browse Code »

    Fix various silly problems wrt mnt_namespace.h:

    - exit_mnt_ns() isn't used, remove it
    - done that, sched.h and nsproxy.h inclusions aren't needed
    - mount.h inclusion was need for vfsmount_lock, but no longer
    - remove mnt_namespace.h inclusion from files which don't use anything
    from mnt_namespace.h

    Signed-off-by: Alexey Dobriyan
    Signed-off-by: Linus Torvalds

    Alexey Dobriyan
     

12 Mar, 2009

1 commit

23 Oct, 2008

1 commit

08 Feb, 2008

1 commit

13 Dec, 2007

1 commit

  • a10db50a4   NFS: Fix an Oops in NFS unmount ... Browse Code »

    Ensure that the dummy 'root dentry' is invisible to d_find_alias(). If not,
    then it may be spliced into the tree if a parent directory from the same
    filesystem gets mounted at a later time.

    Signed-off-by: Trond Myklebust

    Trond Myklebust
     

18 Nov, 2007

1 commit

  • b09b9417d   NFS: Fix the ustat() regression ... Browse Code »

    Since 2.6.18, the superblock sb->s_root has been a dummy dentry with a
    dummy inode. This breaks ustat(), which actually uses sb->s_root in a
    vfstat() call.

    Fix this by making the s_root a dummy alias to the directory inode that was
    used when creating the superblock.

    Signed-off-by: Trond Myklebust

    Trond Myklebust
     

29 Sep, 2007

1 commit

  • 54af3bb54   NFS: Fix an Oops in encode_lookup() ... Browse Code »

    It doesn't look as if the NFS file name limit is being initialised correctly
    in the struct nfs_server. Make sure that we limit whatever is being set in
    nfs_probe_fsinfo() and nfs_init_server().

    Also ensure that readdirplus and nfs4_path_walk respect our file name
    limits.

    Signed-off-by: Trond Myklebust
    Signed-off-by: Linus Torvalds

    Trond Myklebust
     

10 May, 2007

1 commit

09 May, 2007

1 commit

04 Feb, 2007

1 commit

09 Dec, 2006

1 commit

  • 6b3286ed1   [PATCH] rename struct namespace to struct mnt_namespace ... Browse Code »

    Rename 'struct namespace' to 'struct mnt_namespace' to avoid confusion with
    other namespaces being developped for the containers : pid, uts, ipc, etc.
    'namespace' variables and attributes are also renamed to 'mnt_ns'

    Signed-off-by: Kirill Korotaev
    Signed-off-by: Cedric Le Goater
    Cc: Eric W. Biederman
    Cc: Herbert Poetzl
    Cc: Sukadev Bhattiprolu
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Kirill Korotaev
     

04 Oct, 2006

1 commit

23 Sep, 2006

2 commits

  • 738a35195   NFS: Secure the roots of the NFS subtrees in a shared superblock ... Browse Code »

    Invoke security_d_instantiate() on root dentries after allocating them with
    dentry_alloc_anon(). Normally dentry_alloc_root() would do that, but we don't
    call that as we don't want to assign a name to the root dentry at this point
    (we may discover the real name later).

    Signed-Off-By: David Howells
    Signed-off-by: Trond Myklebust

    David Howells
     
  • 54ceac451   NFS: Share NFS superblocks per-protocol per-server per-FSID ... Browse Code »

    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: David Howells
    Signed-off-by: Trond Myklebust

    David Howells