On Wed, Feb 20 2019 at 10:08am -0500, Mikulas Patocka <[email protected]> wrote:
> > > On Tue, 19 Feb 2019, Mike Snitzer wrote: > > > noclone_endio() must call the target's ->endio method if it exists. > > Also must handle the various DM_ENDIO_* returns that are possible. > > > > Factor out dm_bio_pushback_needed() for both dec_pending() and > > noclone_endio() to use when handling BLK_STS_DM_REQUEUE. > > > > Lastly, there is no need to conditionally set md->immutable_target in > > __bind(). If the device only uses a single immutable target then it > > should always be reflected in md->immutable_target. This is important > > because noclone_endio() benefits from this to get access to the > > multipath dm_target without needing to add another member to the > > 'dm_noclone' structure. > > > > Signed-off-by: Mike Snitzer <[email protected]> > > --- > > drivers/md/dm.c | 77 > > ++++++++++++++++++++++++++++++++++++++++----------------- > > 1 file changed, 55 insertions(+), 22 deletions(-) > > > > diff --git a/drivers/md/dm.c b/drivers/md/dm.c > > index 8ff0ced278d7..2299f946c175 100644 > > --- a/drivers/md/dm.c > > +++ b/drivers/md/dm.c > > @@ -897,6 +897,28 @@ static int __noflush_suspending(struct mapped_device > > *md) > > return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); > > } > > > > +static bool dm_bio_pushback_needed(struct mapped_device *md, > > + struct bio *bio, blk_status_t *error) > > +{ > > + unsigned long flags; > > + > > + /* > > + * Target requested pushing back the I/O. > > + */ > > + if (__noflush_suspending(md)) { > > + spin_lock_irqsave(&md->deferred_lock, flags); > > + // FIXME: using bio_list_add_head() creates LIFO > > + bio_list_add_head(&md->deferred, bio); > > + spin_unlock_irqrestore(&md->deferred_lock, flags); > > + return true; > > + } else { > > + /* noflush suspend was interrupted. */ > > + *error = BLK_STS_IOERR; > > + } > > + > > + return false; > > +} > > + > > /* > > * Decrements the number of outstanding ios that a bio has been > > * cloned into, completing the original io if necc. > > @@ -917,19 +939,8 @@ static void dec_pending(struct dm_io *io, blk_status_t > > error) > > } > > > > if (atomic_dec_and_test(&io->io_count)) { > > - if (io->status == BLK_STS_DM_REQUEUE) { > > - /* > > - * Target requested pushing back the I/O. > > - */ > > - spin_lock_irqsave(&md->deferred_lock, flags); > > - if (__noflush_suspending(md)) > > - /* NOTE early return due to BLK_STS_DM_REQUEUE > > below */ > > - bio_list_add_head(&md->deferred, io->orig_bio); > > - else > > - /* noflush suspend was interrupted. */ > > - io->status = BLK_STS_IOERR; > > - spin_unlock_irqrestore(&md->deferred_lock, flags); > > - } > > + if (unlikely(io->status == BLK_STS_DM_REQUEUE)) > > + (void) dm_bio_pushback_needed(md, bio, &io->status); > > This triggers compiler warning because the variable bio is uninitialized > here. Right, I fixed it up in latest git, please see latest 'dm-5.1' branch: https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git/log/?h=dm-5.1 -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
