From: Darrick J. Wong <djwong@xxxxxxxxxx> All online repair functions have the same structure: walk filesystem metadata structures gathering enough data to rebuild the structure, stage a new copy, and then commit the new copy. The gathering steps do not write anything to disk, so they are peppered with xchk_should_terminate calls to avoid softlockup warnings and to provide an opportunity to abort the repair (by killing xfs_scrub). However, it's not clear in the code base when is the last chance to abort cleanly without having to undo a bunch of structure. Therefore, add one more call to xchk_should_terminate (along with a comment) providing the sysadmin with the ability to abort before it's too late and to make it clear in the source code when it's no longer convenient or safe to abort a repair. As there are only four repair functions right now, this patch exists more to establish a precedent for subsequent additions than to deliver practical functionality. Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx> --- fs/xfs/scrub/agheader_repair.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/fs/xfs/scrub/agheader_repair.c b/fs/xfs/scrub/agheader_repair.c index 7874ae8149ca..d54edd0d8538 100644 --- a/fs/xfs/scrub/agheader_repair.c +++ b/fs/xfs/scrub/agheader_repair.c @@ -50,6 +50,10 @@ xrep_superblock( if (error) return error; + /* Last chance to abort before we start committing fixes. */ + if (xchk_should_terminate(sc, &error)) + return error; + /* Copy AG 0's superblock to this one. */ xfs_buf_zero(bp, 0, BBTOB(bp->b_length)); xfs_sb_to_disk(bp->b_addr, &mp->m_sb); @@ -425,6 +429,10 @@ xrep_agf( if (error) return error; + /* Last chance to abort before we start committing fixes. */ + if (xchk_should_terminate(sc, &error)) + return error; + /* Start rewriting the header and implant the btrees we found. */ xrep_agf_init_header(sc, agf_bp, &old_agf); xrep_agf_set_roots(sc, agf, fab); @@ -749,6 +757,10 @@ xrep_agfl( if (error) goto err; + /* Last chance to abort before we start committing fixes. */ + if (xchk_should_terminate(sc, &error)) + goto err; + /* * Update AGF and AGFL. We reset the global free block counter when * we adjust the AGF flcount (which can fail) so avoid updating any @@ -996,6 +1008,10 @@ xrep_agi( if (error) return error; + /* Last chance to abort before we start committing fixes. */ + if (xchk_should_terminate(sc, &error)) + return error; + /* Start rewriting the header and implant the btrees we found. */ xrep_agi_init_header(sc, agi_bp, &old_agi); xrep_agi_set_roots(sc, agi, fab);
