illumos/illumos-gate@42b141117242b1411172https://www.illumos.org/issues/8648
I'm opening this bug to track integration of the following ZFS on Linux
commit into illumos:
commit f763c3d1df
Author: LOLi <loli10K@users.noreply.github.com>
Date: Mon Aug 21 17:59:48 2017 +0200
Fix range locking in ZIL commit codepath
Since OpenZFS 7578 (1b7c1e5) if we have a ZVOL with logbias=throughput
we will force WR_INDIRECT itxs in zvol_log_write() setting itx->itx_lr
offset and length to the offset and length of the BIO from
zvol_write()->zvol_log_write(): these offset and length are later used
to take a range lock in zillog->zl_get_data function: zvol_get_data().
Now suppose we have a ZVOL with blocksize=8K and push 4K writes to
offset 0: we will only be range-locking 0-4096. This means the
ASSERTion we make in dbuf_unoverride() is no longer valid because now
dmu_sync() is called from zilog's get_data functions holding a partial
lock on the dbuf.
Fix this by taking a range lock on the whole block in zvol_get_data().
Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Reviewed by: Alexander Motin <mav@FreeBSD.org>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: LOLi <loli10K@users.noreply.github.com>
MFC after: 10 days
f94aa61c33