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xfs: fix broken icreate log item cancellation
Inode cluster buffers are invalidated and cancelled when inode chunks are freed to notify log recovery that previous logged updates to the metadata buffer should be skipped. This ensures that log recovery does not overwrite buffers that might have already been reused. On v4 filesystems, inode chunk allocation and inode updates are logged via the cluster buffers and thus cancellation is easily detected via buffer cancellation items. v5 filesystems use the new icreate transaction, which uses logical logging and ordered buffers to log a full inode chunk allocation at once. The resulting icreate item often spans multiple inode cluster buffers. Log recovery checks for cancelled buffers when processing icreate log items, but it has a couple problems. First, it uses the full length of the inode chunk rather than the cluster size. Second, it uses the length in FSB units rather than BB units. Either of these problems prevent icreate recovery from identifying cancelled buffers and thus inode initialization proceeds unconditionally. Update xlog_recover_do_icreate_pass2() to iterate the icreate range in cluster sized increments and check each increment for cancellation. Since icreate is currently only used for the minimum atomic inode chunk allocation, we expect that either all or none of the buffers will be cancelled. Cancel the icreate if at least one buffer is cancelled to avoid making a bad situation worse by initializing a partial inode chunk, but detect such anomalies and warn the user. Signed-off-by:Brian Foster <bfoster@redhat.com> Reviewed-by: