"Steven J. Magnani" <st...@digidescorp.com> writes: > On Sat, 2012-07-07 at 06:07 +0900, OGAWA Hirofumi wrote: >> "Steven J. Magnani" <st...@digidescorp.com> writes: >> >> > On Wed, 2012-07-04 at 20:07 +0900, OGAWA Hirofumi wrote: >> >> Please don't add new lock_super() usage if it is not necessary. Almost >> >> all of lock_super() just replaced lock_kernel() usage. It rather should >> >> be removed in future. Probably, this should use inode->i_mutex instead. >> >> >> >> BTW, the above issue is same with all of directory read. >> > >> > I don't think there's really an alternative here. The cases addressed by >> > this patch all involve walking on-disk structures via >> > unofficial/temporary inodes created from information in the NFS handle >> > (i.e., outside the normal inode creation paths). When this process is >> > successful we end up with "official" connected inodes/dentries, but >> > getting there is really a "bottom up" strategy instead of the usual "top >> > down" approach. >> > >> > Because the "bottom up" method is lacking guarantees that "top down" >> > takes for granted - i.e., that a cluster on disk that's supposed to be a >> > directory actually *is* a directory - I am adding some defensive code >> > in the next spin of the patch. >> >> I'm not sure what you meant. Where is the problem? ->get_name()? If so, >> it has parent dentry parameter. What is the wrong if we take >> mutex_lock(parent->d_inode)? > > The temporary/"unofficial" inodes are unhashed and thus not visible > outside of the functions using them. They exist only to support access > to directory contents when we can't gain that access via other means > (because we only have "bottom up" information, about an object and > perhaps its parent, in a form that can't be used to look up hashed > inodes/dentries). Hashing them wouldn't help, because they don't have > the correct key (for instance, in the case of a ".." entry). > > Am I missing something?
You mean the unhashed inode is created by ->get_parent()? If so, the root cause sounds like ->get_parent() itself. If not, I'm not understanding the meaning of the temporary/unofficial inode here. -- OGAWA Hirofumi <hirof...@mail.parknet.co.jp> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
