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bcachefs: Fix extent merging

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When merging extents, we have to check that we won't overflow size
fields in any CRC entries - but the check for this was wrong, because in
the loop it was in we weren't keeping a pointer to the (packed, encoded)
CRC field.

Fix this by moving it to its own loop.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
This commit is contained in:
Kent Overstreet 2022-04-24 23:03:02 -04:00 committed by Kent Overstreet
parent ae21f74e31
commit e320b42dfe
1 changed files with 13 additions and 1 deletions
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14
fs/bcachefs/extents.c
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@ -307,8 +307,20 @@ bool bch2_extent_merge(struct bch_fs *c, struct bkey_s l, struct bkey_s_c r)
lp.crc.uncompressed_size +
rp.crc.uncompressed_size > (c->opts.encoded_extent_max >> 9))
return false;
}
if (lp.crc.uncompressed_size + rp.crc.uncompressed_size >
en_l = extent_entry_next(en_l);
en_r = extent_entry_next(en_r);
}
en_l = l_ptrs.start;
en_r = r_ptrs.start;
while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
if (extent_entry_is_crc(en_l)) {
struct bch_extent_crc_unpacked crc_l = bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
struct bch_extent_crc_unpacked crc_r = bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
if (crc_l.uncompressed_size + crc_r.uncompressed_size >
bch2_crc_field_size_max[extent_entry_type(en_l)])
return false;
}