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If directories can't overflow the extent count in > normal operation, then why are we even calling > xfs_iext_count_may_overflow() in these paths? i.e. an overflow would > be a sign of an inode corruption, and we should have flagged that > long before we do an operation that might overflow the extent count. > > So, really, I think you should document the directory size > constraints at the site where we define all the large extent count > values in xfs_format.h, remove the xfs_iext_count_may_overflow() > checks from the directory code and replace them with a simple inode > verifier check that we haven't got more than 100GB worth of > individual extents in the data fork for directory inodes.... > > Then all this directory specific "can't possibly overflow" overflow > checks can go away completely. The best code is no code :) I had retained the directory extent count overflow checks for the sake of completeness i.e. The code checks for overflow before every fs operation that could cause extent count to increase. However, I think your suggestion makes more sense. I will include this change in the next version of the patchset. -- chandan