| Message ID | 20200917231841.4029747-2-kbusch@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | zoned block device specific errors | expand |
On 2020/09/18 8:18, Keith Busch wrote: > A zoned device with limited resources to open or activate zones may > return an error when the host exceeds those limits. The same command may > be successful if retried later, but the host needs to wait for specific > zone states before it should retry. Have the block layer provide an > appropriate status for these conditions so applications can distinuguish > this error for special handling. > > Cc: Christoph Hellwig <hch@lst.de> > Cc: Damien Le Moal <Damien.LeMoal@wdc.com> > Cc: Johannes Thumshirn <Johannes.Thumshirn@wdc.com> > Signed-off-by: Keith Busch <kbusch@kernel.org> > --- > Documentation/block/queue-sysfs.rst | 8 ++++++++ > block/blk-core.c | 4 ++++ > include/linux/blk_types.h | 18 ++++++++++++++++++ > 3 files changed, 30 insertions(+) > > diff --git a/Documentation/block/queue-sysfs.rst b/Documentation/block/queue-sysfs.rst > index f261a5c84170..2638d3446b79 100644 > --- a/Documentation/block/queue-sysfs.rst > +++ b/Documentation/block/queue-sysfs.rst > @@ -124,6 +124,10 @@ For zoned block devices (zoned attribute indicating "host-managed" or > EXPLICIT OPEN, IMPLICIT OPEN or CLOSED, is limited by this value. > If this value is 0, there is no limit. > > +If the host attempts to exceed this limit, the driver should report this error > +with BLK_STS_ZONE_ACTIVE_RESOURCE, which user space may see as the EOVERFLOW > +errno. > + > max_open_zones (RO) > ------------------- > For zoned block devices (zoned attribute indicating "host-managed" or > @@ -131,6 +135,10 @@ For zoned block devices (zoned attribute indicating "host-managed" or > EXPLICIT OPEN or IMPLICIT OPEN, is limited by this value. > If this value is 0, there is no limit. > > +If the host attempts to exceed this limit, the driver should report this error > +with BLK_STS_ZONE_OPEN_RESOURCE, which user space may see as the ETOOMANYREFS > +errno. > + > max_sectors_kb (RW) > ------------------- > This is the maximum number of kilobytes that the block layer will allow > diff --git a/block/blk-core.c b/block/blk-core.c > index 10c08ac50697..8bffc7732e37 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -186,6 +186,10 @@ static const struct { > /* device mapper special case, should not leak out: */ > [BLK_STS_DM_REQUEUE] = { -EREMCHG, "dm internal retry" }, > > + /* zone device specific errors */ > + [BLK_STS_ZONE_OPEN_RESOURCE] = { -ETOOMANYREFS, "open zones exceeded" }, > + [BLK_STS_ZONE_ACTIVE_RESOURCE] = { -EOVERFLOW, "active zones exceeded" }, > + > /* everything else not covered above: */ > [BLK_STS_IOERR] = { -EIO, "I/O" }, > }; > diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h > index 4ecf4fed171f..8603fc5f86a3 100644 > --- a/include/linux/blk_types.h > +++ b/include/linux/blk_types.h > @@ -103,6 +103,24 @@ typedef u8 __bitwise blk_status_t; > */ > #define BLK_STS_ZONE_RESOURCE ((__force blk_status_t)14) > > +/* > + * BLK_STS_ZONE_OPEN_RESOURCE is returned from the driver in the completion > + * path if the device returns a status indicating that too many zone resources > + * are currently open. The same command should be successful if resubmitted > + * after the number of open zones decreases below the device's limits, which is > + * reported in the request_queue's max_open_zones. > + */ > +#define BLK_STS_ZONE_OPEN_RESOURCE ((__force blk_status_t)15) > + > +/* > + * BLK_STS_ZONE_ACTIVE_RESOURCE is returned from the driver in the completion > + * path if the device returns a status indicating that too many zone resources > + * are currently active. The same command should be successful if resubmitted > + * after the number of active zones decreases below the device's limits, which > + * is reported in the request_queue's max_active_zones. > + */ > +#define BLK_STS_ZONE_ACTIVE_RESOURCE ((__force blk_status_t)16) > + > /** > * blk_path_error - returns true if error may be path related > * @error: status the request was completed with > Looks good. Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
On 18/09/2020 01:18, Keith Busch wrote: > diff --git a/Documentation/block/queue-sysfs.rst b/Documentation/block/queue-sysfs.rst > index f261a5c84170..2638d3446b79 100644 > --- a/Documentation/block/queue-sysfs.rst > +++ b/Documentation/block/queue-sysfs.rst > @@ -124,6 +124,10 @@ For zoned block devices (zoned attribute indicating "host-managed" or > EXPLICIT OPEN, IMPLICIT OPEN or CLOSED, is limited by this value. > If this value is 0, there is no limit. > > +If the host attempts to exceed this limit, the driver should report this error > +with BLK_STS_ZONE_ACTIVE_RESOURCE, which user space may see as the EOVERFLOW > +errno. > + > max_open_zones (RO) > ------------------- > For zoned block devices (zoned attribute indicating "host-managed" or > @@ -131,6 +135,10 @@ For zoned block devices (zoned attribute indicating "host-managed" or > EXPLICIT OPEN or IMPLICIT OPEN, is limited by this value. > If this value is 0, there is no limit. > > +If the host attempts to exceed this limit, the driver should report this error > +with BLK_STS_ZONE_OPEN_RESOURCE, which user space may see as the ETOOMANYREFS > +errno. Don't we also need to update some man pages in section 2? Code wise, Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
On Fri, Sep 18, 2020 at 01:31:44PM +0000, Johannes Thumshirn wrote: > On 18/09/2020 01:18, Keith Busch wrote: > > diff --git a/Documentation/block/queue-sysfs.rst b/Documentation/block/queue-sysfs.rst > > index f261a5c84170..2638d3446b79 100644 > > --- a/Documentation/block/queue-sysfs.rst > > +++ b/Documentation/block/queue-sysfs.rst > > @@ -124,6 +124,10 @@ For zoned block devices (zoned attribute indicating "host-managed" or > > EXPLICIT OPEN, IMPLICIT OPEN or CLOSED, is limited by this value. > > If this value is 0, there is no limit. > > > > +If the host attempts to exceed this limit, the driver should report this error > > +with BLK_STS_ZONE_ACTIVE_RESOURCE, which user space may see as the EOVERFLOW > > +errno. > > + > > max_open_zones (RO) > > ------------------- > > For zoned block devices (zoned attribute indicating "host-managed" or > > @@ -131,6 +135,10 @@ For zoned block devices (zoned attribute indicating "host-managed" or > > EXPLICIT OPEN or IMPLICIT OPEN, is limited by this value. > > If this value is 0, there is no limit. > > > > +If the host attempts to exceed this limit, the driver should report this error > > +with BLK_STS_ZONE_OPEN_RESOURCE, which user space may see as the ETOOMANYREFS > > +errno. > > Don't we also need to update some man pages in section 2? Yes, good point. Those updates need to come from this repo https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git right? If so, I can send updates there once it looks like this is the form that will be committed.
On 18/09/2020 21:41, Keith Busch wrote: [...] > > Yes, good point. Those updates need to come from this repo > > https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git > > right? If so, I can send updates there once it looks like this is the > form that will be committed. > I think so yes. Should we also Cc linux-api on this matter?
diff --git a/Documentation/block/queue-sysfs.rst b/Documentation/block/queue-sysfs.rst index f261a5c84170..2638d3446b79 100644 --- a/Documentation/block/queue-sysfs.rst +++ b/Documentation/block/queue-sysfs.rst @@ -124,6 +124,10 @@ For zoned block devices (zoned attribute indicating "host-managed" or EXPLICIT OPEN, IMPLICIT OPEN or CLOSED, is limited by this value. If this value is 0, there is no limit. +If the host attempts to exceed this limit, the driver should report this error +with BLK_STS_ZONE_ACTIVE_RESOURCE, which user space may see as the EOVERFLOW +errno. + max_open_zones (RO) ------------------- For zoned block devices (zoned attribute indicating "host-managed" or @@ -131,6 +135,10 @@ For zoned block devices (zoned attribute indicating "host-managed" or EXPLICIT OPEN or IMPLICIT OPEN, is limited by this value. If this value is 0, there is no limit. +If the host attempts to exceed this limit, the driver should report this error +with BLK_STS_ZONE_OPEN_RESOURCE, which user space may see as the ETOOMANYREFS +errno. + max_sectors_kb (RW) ------------------- This is the maximum number of kilobytes that the block layer will allow diff --git a/block/blk-core.c b/block/blk-core.c index 10c08ac50697..8bffc7732e37 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -186,6 +186,10 @@ static const struct { /* device mapper special case, should not leak out: */ [BLK_STS_DM_REQUEUE] = { -EREMCHG, "dm internal retry" }, + /* zone device specific errors */ + [BLK_STS_ZONE_OPEN_RESOURCE] = { -ETOOMANYREFS, "open zones exceeded" }, + [BLK_STS_ZONE_ACTIVE_RESOURCE] = { -EOVERFLOW, "active zones exceeded" }, + /* everything else not covered above: */ [BLK_STS_IOERR] = { -EIO, "I/O" }, }; diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 4ecf4fed171f..8603fc5f86a3 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -103,6 +103,24 @@ typedef u8 __bitwise blk_status_t; */ #define BLK_STS_ZONE_RESOURCE ((__force blk_status_t)14) +/* + * BLK_STS_ZONE_OPEN_RESOURCE is returned from the driver in the completion + * path if the device returns a status indicating that too many zone resources + * are currently open. The same command should be successful if resubmitted + * after the number of open zones decreases below the device's limits, which is + * reported in the request_queue's max_open_zones. + */ +#define BLK_STS_ZONE_OPEN_RESOURCE ((__force blk_status_t)15) + +/* + * BLK_STS_ZONE_ACTIVE_RESOURCE is returned from the driver in the completion + * path if the device returns a status indicating that too many zone resources + * are currently active. The same command should be successful if resubmitted + * after the number of active zones decreases below the device's limits, which + * is reported in the request_queue's max_active_zones. + */ +#define BLK_STS_ZONE_ACTIVE_RESOURCE ((__force blk_status_t)16) + /** * blk_path_error - returns true if error may be path related * @error: status the request was completed with
A zoned device with limited resources to open or activate zones may return an error when the host exceeds those limits. The same command may be successful if retried later, but the host needs to wait for specific zone states before it should retry. Have the block layer provide an appropriate status for these conditions so applications can distinuguish this error for special handling. Cc: Christoph Hellwig <hch@lst.de> Cc: Damien Le Moal <Damien.LeMoal@wdc.com> Cc: Johannes Thumshirn <Johannes.Thumshirn@wdc.com> Signed-off-by: Keith Busch <kbusch@kernel.org> --- Documentation/block/queue-sysfs.rst | 8 ++++++++ block/blk-core.c | 4 ++++ include/linux/blk_types.h | 18 ++++++++++++++++++ 3 files changed, 30 insertions(+)