From: Tejun Heo Date: Fri, 10 Jan 2014 13:57:23 +0000 (-0500) Subject: kernfs: invoke kernfs_unmap_bin_file() directly from __kernfs_remove() X-Git-Tag: v3.14-rc1~151^2~28 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f601f9a2bf7dc1f7ee18feece4c4e2fc6845d6c4;p=pandora-kernel.git 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 Signed-off-by: Greg Kroah-Hartman --- Reading git-diff-tree failed