| Message ID | 20170515152839.23375-5-hch@lst.de (mailing list archive) |
|---|---|
| State | Deferred, archived |
| Delegated to: | Mike Snitzer |
| Headers | show |
On Mon, May 15 2017 at 11:28P -0400, Christoph Hellwig <hch@lst.de> wrote: > A few (but not all) dm targets use a special EWOULDBLOCK error code for > failing REQ_RAHEAD requests that fail due to a lack of available resources. > But no one else knows about this magic code, and lower level drivers also > don't generate it when failing read-ahead requests for similar reasons. > > So remove this special casing and ignore all additional error handling for > REQ_RAHEAD - if this was a real underlying error we'd get a normal read > once the real read comes in. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/md/dm-raid1.c | 4 ++-- > drivers/md/dm-stripe.c | 2 +- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c > index a95cbb80fb34..5e30b08b91d9 100644 > --- a/drivers/md/dm-raid1.c > +++ b/drivers/md/dm-raid1.c > @@ -1214,7 +1214,7 @@ static int mirror_map(struct dm_target *ti, struct bio *bio) > */ > if (!r || (r == -EWOULDBLOCK)) { > if (bio->bi_opf & REQ_RAHEAD) > - return -EWOULDBLOCK; > + return -EIO; > > queue_bio(ms, bio, rw); > return DM_MAPIO_SUBMITTED; > @@ -1258,7 +1258,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error) > if (error == -EOPNOTSUPP) > return error; > > - if ((error == -EWOULDBLOCK) && (bio->bi_opf & REQ_RAHEAD)) > + if (bio->bi_opf & REQ_RAHEAD) > return error; > > if (unlikely(error)) { > diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c > index 75152482f3ad..780e95889a7c 100644 > --- a/drivers/md/dm-stripe.c > +++ b/drivers/md/dm-stripe.c > @@ -384,7 +384,7 @@ static int stripe_end_io(struct dm_target *ti, struct bio *bio, int error) > if (!error) > return 0; /* I/O complete */ > > - if ((error == -EWOULDBLOCK) && (bio->bi_opf & REQ_RAHEAD)) > + if (bio->bi_opf & REQ_RAHEAD) > return error; > > if (error == -EOPNOTSUPP) > -- > 2.11.0 > I'll let this one go for now.. meaning I won't pick it up, nor will I send it for 4.12. Please just roll this into your broader block work that you mentioned. -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c index a95cbb80fb34..5e30b08b91d9 100644 --- a/drivers/md/dm-raid1.c +++ b/drivers/md/dm-raid1.c @@ -1214,7 +1214,7 @@ static int mirror_map(struct dm_target *ti, struct bio *bio) */ if (!r || (r == -EWOULDBLOCK)) { if (bio->bi_opf & REQ_RAHEAD) - return -EWOULDBLOCK; + return -EIO; queue_bio(ms, bio, rw); return DM_MAPIO_SUBMITTED; @@ -1258,7 +1258,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error) if (error == -EOPNOTSUPP) return error; - if ((error == -EWOULDBLOCK) && (bio->bi_opf & REQ_RAHEAD)) + if (bio->bi_opf & REQ_RAHEAD) return error; if (unlikely(error)) { diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c index 75152482f3ad..780e95889a7c 100644 --- a/drivers/md/dm-stripe.c +++ b/drivers/md/dm-stripe.c @@ -384,7 +384,7 @@ static int stripe_end_io(struct dm_target *ti, struct bio *bio, int error) if (!error) return 0; /* I/O complete */ - if ((error == -EWOULDBLOCK) && (bio->bi_opf & REQ_RAHEAD)) + if (bio->bi_opf & REQ_RAHEAD) return error; if (error == -EOPNOTSUPP)
A few (but not all) dm targets use a special EWOULDBLOCK error code for failing REQ_RAHEAD requests that fail due to a lack of available resources. But no one else knows about this magic code, and lower level drivers also don't generate it when failing read-ahead requests for similar reasons. So remove this special casing and ignore all additional error handling for REQ_RAHEAD - if this was a real underlying error we'd get a normal read once the real read comes in. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/md/dm-raid1.c | 4 ++-- drivers/md/dm-stripe.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)