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| author | Tejun Heo <tj@kernel.org> | 2014-01-10 17:57:23 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-01-11 01:48:08 +0400 |
| commit | f601f9a2bf7dc1f7ee18feece4c4e2fc6845d6c4 (patch) | |
| tree | f8213b3d7542c85c42cb1a20668098609d65762c /fs/kernfs/kernfs-internal.h | |
| parent | 45a140e587f3d32d8d424ed940dffb61e1739047 (diff) | |
| download | linux-f601f9a2bf7dc1f7ee18feece4c4e2fc6845d6c4.tar.xz | |
kernfs: invoke kernfs_unmap_bin_file() directly from __kernfs_remove()
kernfs_unmap_bin_file() is supposed to unmap all memory mappings of
the target file before kernfs_remove() finishes; however, it currently
is being called from kernfs_addrm_finish() and has the same race
problem as the original implementation of deactivation when there are
multiple removers - only the remover which snatches the node to its
addrm_cxt->removed list is guaranteed to wait for its completion
before returning.
It can be fixed by moving kernfs_unmap_bin_file() invocation from
kernfs_addrm_finish() to __kernfs_remove(). The function may be
called multiple times but that shouldn't do any harm.
We end up dropping kernfs_mutex in the removal loop and the node may
be removed inbetween by someone else. kernfs_unlink_sibling() is
updated to test whether the node has already been removed and return
accordingly. __kernfs_remove() in turn performs post-unlinking
cleanup only if it actually unlinked the node.
KERNFS_HAS_MMAP test is moved out of the unmap function into
__kernfs_remove() so that we don't unlock kernfs_mutex unnecessarily.
While at it, drop the now meaningless "bin" qualifier from the
function name.
v2: Rewritten to fit the v2 restructuring of removal path. HAS_MMAP
test relocated.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/kernfs/kernfs-internal.h')
| -rw-r--r-- | fs/kernfs/kernfs-internal.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h index 57a93f4d645c..e9ec38c86074 100644 --- a/fs/kernfs/kernfs-internal.h +++ b/fs/kernfs/kernfs-internal.h @@ -113,7 +113,7 @@ struct kernfs_node *kernfs_new_node(struct kernfs_root *root, const char *name, */ extern const struct file_operations kernfs_file_fops; -void kernfs_unmap_bin_file(struct kernfs_node *kn); +void kernfs_unmap_file(struct kernfs_node *kn); /* * symlink.c |