Message ID | 20200914003448.471624-2-damien.lemoal@wdc.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Fix handling of host-aware ZBC disks | expand |
On Mon, Sep 14, 2020 at 09:34:47AM +0900, Damien Le Moal wrote: > When CONFIG_BLK_DEV_ZONED is disabled, allow using host-aware ZBC > disks as regular disks. In this case, ensure that command completion > is correctly executed by changing sd_zbc_complete() to return good_bytes > instead of 0, causing a hang during device probe (endless retries). > > When CONFIG_BLK_DEV_ZONED is enabled and a host-aware disk is detected > to have partitions, it will be used as a regular disk. In this case, > make sure to not do anything in sd_zbc_revalidate_zones() as that > triggers warnings. > > Reported-by: Borislav Petkov <bp@alien8.de> > Fixes: b72053072c0b ("block: allow partitions on host aware zone devices") > Cc: <stable@vger.kernel.org> > Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> > Tested-by: Borislav Petkov <bp@suse.de> > Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> > --- > drivers/scsi/sd.c | 28 ++++++++++++++++++++++------ > drivers/scsi/sd.h | 2 +- > drivers/scsi/sd_zbc.c | 6 +++++- > 3 files changed, 28 insertions(+), 8 deletions(-) > > } else { > sdkp->zoned = (buffer[8] >> 4) & 3; > if (sdkp->zoned == 1 && !disk_has_partitions(sdkp->disk)) { > + /* > + * Host-aware disk without partition: use the disk as > + * such if support for zoned block devices is enabled. > + * Otherwise, use it as a regular disk. > + */ > + if (IS_ENABLED(CONFIG_BLK_DEV_ZONED)) > + q->limits.zoned = BLK_ZONED_HA; > + else > + q->limits.zoned = BLK_ZONED_NONE; > } else { > /* > * Treat drive-managed devices and host-aware devices > * with partitions as regular block devices. > */ > q->limits.zoned = BLK_ZONED_NONE; > } I think we need to lift much of this into a block layer helper, as the logic is way subtile. Something like this (written in the MUA editor, not even compile tested). static inline void blk_queue_set_zoned(struct gendisk *disk, enum blk_zoned_model model) { switch (model) { case BLK_ZONED_HM: WARN_ON_ONCE(!IS_ENABLED(CONFIG_BLK_DEV_ZONED)); break; /* * Host aware drivers are neither fish nor fowl. We can either * treat them like a drive managed devices, in which case they * aren't different from a normal block device, or we can try * to take advantage of the Zone command set, but in that case * we need to treat them like a host managed device. We try * the latter if there are not partitions and zoned block device * set support is enabled, else we do nothing special as far as * the block layer is concerned. */ case BLK_ZONED_HA: if (!IS_ENABLED(CONFIG_BLK_DEV_ZONED) || disk_has_partitions(disk)) { model = BLK_ZONED_NONE; break; default: break; disk->queue->limits.zoned = model; } Then in sd do: if (sdkp->device->type == TYPE_ZBC) { blk_queue_set_zoned(sdkp->disk, BLK_ZONED_HM); } else { sdkp->zoned = (buffer[8] >> 4) & 3; if (sdkp->zoned == 1) blk_queue_set_zoned(sdkp->disk, BLK_ZONED_HA); else blk_queue_set_zoned(sdkp->disk, BLK_ZONED_NONE); }
On 2020/09/14 16:20, Christoph Hellwig wrote: > On Mon, Sep 14, 2020 at 09:34:47AM +0900, Damien Le Moal wrote: >> When CONFIG_BLK_DEV_ZONED is disabled, allow using host-aware ZBC >> disks as regular disks. In this case, ensure that command completion >> is correctly executed by changing sd_zbc_complete() to return good_bytes >> instead of 0, causing a hang during device probe (endless retries). >> >> When CONFIG_BLK_DEV_ZONED is enabled and a host-aware disk is detected >> to have partitions, it will be used as a regular disk. In this case, >> make sure to not do anything in sd_zbc_revalidate_zones() as that >> triggers warnings. >> >> Reported-by: Borislav Petkov <bp@alien8.de> >> Fixes: b72053072c0b ("block: allow partitions on host aware zone devices") >> Cc: <stable@vger.kernel.org> >> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> >> Tested-by: Borislav Petkov <bp@suse.de> >> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> >> --- >> drivers/scsi/sd.c | 28 ++++++++++++++++++++++------ >> drivers/scsi/sd.h | 2 +- >> drivers/scsi/sd_zbc.c | 6 +++++- >> 3 files changed, 28 insertions(+), 8 deletions(-) >> >> } else { >> sdkp->zoned = (buffer[8] >> 4) & 3; >> if (sdkp->zoned == 1 && !disk_has_partitions(sdkp->disk)) { >> + /* >> + * Host-aware disk without partition: use the disk as >> + * such if support for zoned block devices is enabled. >> + * Otherwise, use it as a regular disk. >> + */ >> + if (IS_ENABLED(CONFIG_BLK_DEV_ZONED)) >> + q->limits.zoned = BLK_ZONED_HA; >> + else >> + q->limits.zoned = BLK_ZONED_NONE; >> } else { >> /* >> * Treat drive-managed devices and host-aware devices >> * with partitions as regular block devices. >> */ >> q->limits.zoned = BLK_ZONED_NONE; >> } > > I think we need to lift much of this into a block layer helper, > as the logic is way subtile. Something like this (written in the MUA > editor, not even compile tested). > > static inline void blk_queue_set_zoned(struct gendisk *disk, > enum blk_zoned_model model) > { > switch (model) { > case BLK_ZONED_HM: > WARN_ON_ONCE(!IS_ENABLED(CONFIG_BLK_DEV_ZONED)); > break; > /* > * Host aware drivers are neither fish nor fowl. We can either > * treat them like a drive managed devices, in which case they > * aren't different from a normal block device, or we can try > * to take advantage of the Zone command set, but in that case > * we need to treat them like a host managed device. We try > * the latter if there are not partitions and zoned block device > * set support is enabled, else we do nothing special as far as > * the block layer is concerned. > */ > case BLK_ZONED_HA: > if (!IS_ENABLED(CONFIG_BLK_DEV_ZONED) || > disk_has_partitions(disk)) { > model = BLK_ZONED_NONE; > break; > default: > break; > > disk->queue->limits.zoned = model; > } > > Then in sd do: > > if (sdkp->device->type == TYPE_ZBC) { > blk_queue_set_zoned(sdkp->disk, BLK_ZONED_HM); > } else { > sdkp->zoned = (buffer[8] >> 4) & 3; > if (sdkp->zoned == 1) > blk_queue_set_zoned(sdkp->disk, BLK_ZONED_HA); > else > blk_queue_set_zoned(sdkp->disk, BLK_ZONED_NONE); > } > Yes, that's nice. Will send something along these lines. But since this is a bug fix for the current cycle & stable, we probably should keep the patch as is and add the improvement on top for 5.10, no ?
On Mon, Sep 14, 2020 at 09:03:49AM +0000, Damien Le Moal wrote: > Yes, that's nice. Will send something along these lines. But since this is a bug > fix for the current cycle & stable, we probably should keep the patch as is and > add the improvement on top for 5.10, no ? I'd much rather also add the trivial helper for 5.9 - otherwise we'll need to pull current mainline into the for-5.10 tree and create all kinds of mess. And just adding the helper and using it for sd only will have no side effects elsewhere.
On 2020/09/14 23:20, hch@infradead.org wrote: > On Mon, Sep 14, 2020 at 09:03:49AM +0000, Damien Le Moal wrote: >> Yes, that's nice. Will send something along these lines. But since this is a bug >> fix for the current cycle & stable, we probably should keep the patch as is and >> add the improvement on top for 5.10, no ? > > I'd much rather also add the trivial helper for 5.9 - otherwise we'll > need to pull current mainline into the for-5.10 tree and create > all kinds of mess. And just adding the helper and using it for sd > only will have no side effects elsewhere. > OK. Sending a v3 with this added.
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 95018e650f2d..e99f57bfeff4 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2968,22 +2968,38 @@ static void sd_read_block_characteristics(struct scsi_disk *sdkp) } else { sdkp->zoned = (buffer[8] >> 4) & 3; if (sdkp->zoned == 1 && !disk_has_partitions(sdkp->disk)) { - /* Host-aware */ - q->limits.zoned = BLK_ZONED_HA; + /* + * Host-aware disk without partition: use the disk as + * such if support for zoned block devices is enabled. + * Otherwise, use it as a regular disk. + */ + if (IS_ENABLED(CONFIG_BLK_DEV_ZONED)) + q->limits.zoned = BLK_ZONED_HA; + else + q->limits.zoned = BLK_ZONED_NONE; } else { /* * Treat drive-managed devices and host-aware devices * with partitions as regular block devices. */ q->limits.zoned = BLK_ZONED_NONE; - if (sdkp->zoned == 2 && sdkp->first_scan) - sd_printk(KERN_NOTICE, sdkp, - "Drive-managed SMR disk\n"); } } - if (blk_queue_is_zoned(q) && sdkp->first_scan) + + if (!sdkp->first_scan) + goto out; + + if (blk_queue_is_zoned(q)) { sd_printk(KERN_NOTICE, sdkp, "Host-%s zoned block device\n", q->limits.zoned == BLK_ZONED_HM ? "managed" : "aware"); + } else { + if (sdkp->zoned == 1) + sd_printk(KERN_NOTICE, sdkp, + "Host-aware SMR disk used as regular disk\n"); + else if (sdkp->zoned == 2) + sd_printk(KERN_NOTICE, sdkp, + "Drive-managed SMR disk\n"); + } out: kfree(buffer); diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h index 4933e7daf17d..7251434100e6 100644 --- a/drivers/scsi/sd.h +++ b/drivers/scsi/sd.h @@ -259,7 +259,7 @@ static inline blk_status_t sd_zbc_setup_zone_mgmt_cmnd(struct scsi_cmnd *cmd, static inline unsigned int sd_zbc_complete(struct scsi_cmnd *cmd, unsigned int good_bytes, struct scsi_sense_hdr *sshdr) { - return 0; + return good_bytes; } static inline blk_status_t sd_zbc_prepare_zone_append(struct scsi_cmnd *cmd, diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c index 0e94ff056bff..a739456dea02 100644 --- a/drivers/scsi/sd_zbc.c +++ b/drivers/scsi/sd_zbc.c @@ -667,7 +667,11 @@ int sd_zbc_revalidate_zones(struct scsi_disk *sdkp) u32 max_append; int ret = 0; - if (!sd_is_zoned(sdkp)) + /* + * There is nothing to do for regular disks, including host-aware disks + * that have partitions. + */ + if (!blk_queue_is_zoned(q)) return 0; /*