| Message ID | 1484596878.2540.58.camel@HansenPartnership.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
>>>>> "James" == James Bottomley <James.Bottomley@HansenPartnership.com> writes:
James> Subject: [PATCH] scsi: mpt3sas: fix hang on ata passthrough
James> commands
James> mpt3sas has a firmware failure where it can only handle one pass
James> through ATA command at a time. If another comes in, contrary to
James> the SAT standard, it will hang until the first one completes
James> (causing long commands like secure erase to timeout). The
James> original fix was to block the device when an ATA command came in,
James> but this caused a regression with
Broadcom folks: Please test and ack as soon as possible so we can get
this fix queued up.
Ingo: Since you appear to have hardware, it would be great if you could
test James' v3 (https://patchwork.kernel.org/patch/9519383/). Sorry for
the inconvenience.
On Tue, Jan 17, 2017 at 1:31 AM, James Bottomley <James.Bottomley@hansenpartnership.com> wrote: > From 91d249409546569444897a1ffde65c421e064899 Mon Sep 17 00:00:00 2001 > From: James Bottomley <James.Bottomley@HansenPartnership.com> > Date: Sun, 1 Jan 2017 09:39:24 -0800 > Subject: [PATCH] scsi: mpt3sas: fix hang on ata passthrough commands > > mpt3sas has a firmware failure where it can only handle one pass > through ATA command at a time. If another comes in, contrary to the > SAT standard, it will hang until the first one completes (causing long > commands like secure erase to timeout). The original fix was to block > the device when an ATA command came in, but this caused a regression > with > > commit 669f044170d8933c3d66d231b69ea97cb8447338 > Author: Bart Van Assche <bart.vanassche@sandisk.com> > Date: Tue Nov 22 16:17:13 2016 -0800 > > scsi: srp_transport: Move queuecommand() wait code to SCSI core > > So fix the original fix of the secure erase timeout by properly > returning SAM_STAT_BUSY like the SAT recommends. The original patch > also had a concurrency problem since scsih_qcmd is lockless at that > point (this is fixed by using atomic bitops to set and test the flag). > > Fixes: 18f6084a989ba1b (mpt3sas: Fix secure erase premature termination) > Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> > > --- > > v2 - use bitops for lockless atomicity > v3 - update description, change function name > --- > drivers/scsi/mpt3sas/mpt3sas_base.h | 12 +++++++++++ > drivers/scsi/mpt3sas/mpt3sas_scsih.c | 40 +++++++++++++++++++++++------------- > 2 files changed, 38 insertions(+), 14 deletions(-) > > diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h > index 394fe13..dcb33f4 100644 > --- a/drivers/scsi/mpt3sas/mpt3sas_base.h > +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h > @@ -393,6 +393,7 @@ struct MPT3SAS_TARGET { > * @eedp_enable: eedp support enable bit > * @eedp_type: 0(type_1), 1(type_2), 2(type_3) > * @eedp_block_length: block size > + * @ata_command_pending: SATL passthrough outstanding for device > */ > struct MPT3SAS_DEVICE { > struct MPT3SAS_TARGET *sas_target; > @@ -404,6 +405,17 @@ struct MPT3SAS_DEVICE { > u8 ignore_delay_remove; > /* Iopriority Command Handling */ > u8 ncq_prio_enable; > + /* > + * Bug workaround for SATL handling: the mpt2/3sas firmware > + * doesn't return BUSY or TASK_SET_FULL for subsequent > + * commands while a SATL pass through is in operation as the > + * spec requires, it simply does nothing with them until the > + * pass through completes, causing them possibly to timeout if > + * the passthrough is a long executing command (like format or > + * secure erase). This variable allows us to do the right > + * thing while a SATL command is pending. > + */ > + unsigned long ata_command_pending; > > }; > > diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c > index b5c966e..830e2c1 100644 > --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c > +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c > @@ -3899,9 +3899,18 @@ _scsih_temp_threshold_events(struct MPT3SAS_ADAPTER *ioc, > } > } > > -static inline bool ata_12_16_cmd(struct scsi_cmnd *scmd) > +static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending) > { > - return (scmd->cmnd[0] == ATA_12 || scmd->cmnd[0] == ATA_16); > + struct MPT3SAS_DEVICE *priv = scmd->device->hostdata; > + > + if (scmd->cmnd[0] != ATA_12 && scmd->cmnd[0] != ATA_16) > + return 0; > + > + if (pending) > + return test_and_set_bit(0, &priv->ata_command_pending); > + > + clear_bit(0, &priv->ata_command_pending); > + return 0; > } > > /** > @@ -3925,9 +3934,7 @@ _scsih_flush_running_cmds(struct MPT3SAS_ADAPTER *ioc) > if (!scmd) > continue; > count++; > - if (ata_12_16_cmd(scmd)) > - scsi_internal_device_unblock(scmd->device, > - SDEV_RUNNING); > + _scsih_set_satl_pending(scmd, false); > mpt3sas_base_free_smid(ioc, smid); > scsi_dma_unmap(scmd); > if (ioc->pci_error_recovery) > @@ -4063,13 +4070,6 @@ scsih_qcmd(struct Scsi_Host *shost, struct scsi_cmnd *scmd) > if (ioc->logging_level & MPT_DEBUG_SCSI) > scsi_print_command(scmd); > > - /* > - * Lock the device for any subsequent command until command is > - * done. > - */ > - if (ata_12_16_cmd(scmd)) > - scsi_internal_device_block(scmd->device); > - > sas_device_priv_data = scmd->device->hostdata; > if (!sas_device_priv_data || !sas_device_priv_data->sas_target) { > scmd->result = DID_NO_CONNECT << 16; > @@ -4083,6 +4083,19 @@ scsih_qcmd(struct Scsi_Host *shost, struct scsi_cmnd *scmd) > return 0; > } > > + /* > + * Bug work around for firmware SATL handling. The loop > + * is based on atomic operations and ensures consistency > + * since we're lockless at this point > + */ > + do { > + if (sas_device_priv_data->ata_command_pending) { > + scmd->result = SAM_STAT_BUSY; > + scmd->scsi_done(scmd); > + return 0; > + } > + } while (_scsih_set_satl_pending(scmd, true)); > + [Sreekanth] Just for readability purpose, can use use "if (test_bit(0, &sas_device_priv_data->ata_command_pending)" instead of "if (sas_device_priv_data->ata_command_pending)". Since while setting & clearing the bit we are using atomic bit operations. I don't see any issue functionality wise. > sas_target_priv_data = sas_device_priv_data->sas_target; > > /* invalid device handle */ > @@ -4650,8 +4663,7 @@ _scsih_io_done(struct MPT3SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply) > if (scmd == NULL) > return 1; > > - if (ata_12_16_cmd(scmd)) > - scsi_internal_device_unblock(scmd->device, SDEV_RUNNING); > + _scsih_set_satl_pending(scmd, false); > > mpi_request = mpt3sas_base_get_msg_frame(ioc, smid); > > -- > 2.6.6 > Tested this patch. It is working fine. Please consider this patch as Acked-by: Sreekanth Reddy <Sreekanth.Reddy@broadcom.com> Thanks, Sreekanth -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Jan 17, 2017 at 07:43:51PM +0530, Sreekanth Reddy wrote: > [Sreekanth] Just for readability purpose, can use use "if (test_bit(0, > &sas_device_priv_data->ata_command_pending)" > instead of "if (sas_device_priv_data->ata_command_pending)". > Since while setting & clearing the bit we are using atomic bit > operations. I don't see any issue functionality wise. I agree. Also while we're into nitpicking - it would be good to give bit 0 of the bitmap a name instead of hardcoding the 0. Except for these patch looks fine: Reviewed-by: Christoph Hellwig <hch@lst.de> -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2017-01-17 at 19:43 +0530, Sreekanth Reddy wrote: > On Tue, Jan 17, 2017 at 1:31 AM, James Bottomley > <James.Bottomley@hansenpartnership.com> wrote: > > From 91d249409546569444897a1ffde65c421e064899 Mon Sep 17 00:00:00 > > 2001 > > From: James Bottomley <James.Bottomley@HansenPartnership.com> > > Date: Sun, 1 Jan 2017 09:39:24 -0800 > > Subject: [PATCH] scsi: mpt3sas: fix hang on ata passthrough > > commands > > > > mpt3sas has a firmware failure where it can only handle one pass > > through ATA command at a time. If another comes in, contrary to > > the > > SAT standard, it will hang until the first one completes (causing > > long > > commands like secure erase to timeout). The original fix was to > > block > > the device when an ATA command came in, but this caused a > > regression > > with > > > > commit 669f044170d8933c3d66d231b69ea97cb8447338 > > Author: Bart Van Assche <bart.vanassche@sandisk.com> > > Date: Tue Nov 22 16:17:13 2016 -0800 > > > > scsi: srp_transport: Move queuecommand() wait code to SCSI core > > > > So fix the original fix of the secure erase timeout by properly > > returning SAM_STAT_BUSY like the SAT recommends. The original > > patch > > also had a concurrency problem since scsih_qcmd is lockless at that > > point (this is fixed by using atomic bitops to set and test the > > flag). > > > > Fixes: 18f6084a989ba1b (mpt3sas: Fix secure erase premature > > termination) > > Signed-off-by: James Bottomley < > > James.Bottomley@HansenPartnership.com> > > > > --- > > > > v2 - use bitops for lockless atomicity > > v3 - update description, change function name > > --- > > drivers/scsi/mpt3sas/mpt3sas_base.h | 12 +++++++++++ > > drivers/scsi/mpt3sas/mpt3sas_scsih.c | 40 +++++++++++++++++++++++- > > ------------ > > 2 files changed, 38 insertions(+), 14 deletions(-) > > > > diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h > > b/drivers/scsi/mpt3sas/mpt3sas_base.h > > index 394fe13..dcb33f4 100644 > > --- a/drivers/scsi/mpt3sas/mpt3sas_base.h > > +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h > > @@ -393,6 +393,7 @@ struct MPT3SAS_TARGET { > > * @eedp_enable: eedp support enable bit > > * @eedp_type: 0(type_1), 1(type_2), 2(type_3) > > * @eedp_block_length: block size > > + * @ata_command_pending: SATL passthrough outstanding for device > > */ > > struct MPT3SAS_DEVICE { > > struct MPT3SAS_TARGET *sas_target; > > @@ -404,6 +405,17 @@ struct MPT3SAS_DEVICE { > > u8 ignore_delay_remove; > > /* Iopriority Command Handling */ > > u8 ncq_prio_enable; > > + /* > > + * Bug workaround for SATL handling: the mpt2/3sas firmware > > + * doesn't return BUSY or TASK_SET_FULL for subsequent > > + * commands while a SATL pass through is in operation as > > the > > + * spec requires, it simply does nothing with them until > > the > > + * pass through completes, causing them possibly to timeout > > if > > + * the passthrough is a long executing command (like format > > or > > + * secure erase). This variable allows us to do the right > > + * thing while a SATL command is pending. > > + */ > > + unsigned long ata_command_pending; > > > > }; > > > > diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c > > b/drivers/scsi/mpt3sas/mpt3sas_scsih.c > > index b5c966e..830e2c1 100644 > > --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c > > +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c > > @@ -3899,9 +3899,18 @@ _scsih_temp_threshold_events(struct > > MPT3SAS_ADAPTER *ioc, > > } > > } > > > > -static inline bool ata_12_16_cmd(struct scsi_cmnd *scmd) > > +static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool > > pending) > > { > > - return (scmd->cmnd[0] == ATA_12 || scmd->cmnd[0] == > > ATA_16); > > + struct MPT3SAS_DEVICE *priv = scmd->device->hostdata; > > + > > + if (scmd->cmnd[0] != ATA_12 && scmd->cmnd[0] != ATA_16) > > + return 0; > > + > > + if (pending) > > + return test_and_set_bit(0, &priv > > ->ata_command_pending); > > + > > + clear_bit(0, &priv->ata_command_pending); > > + return 0; > > } > > > > /** > > @@ -3925,9 +3934,7 @@ _scsih_flush_running_cmds(struct > > MPT3SAS_ADAPTER *ioc) > > if (!scmd) > > continue; > > count++; > > - if (ata_12_16_cmd(scmd)) > > - scsi_internal_device_unblock(scmd->device, > > - > > SDEV_RUNNING); > > + _scsih_set_satl_pending(scmd, false); > > mpt3sas_base_free_smid(ioc, smid); > > scsi_dma_unmap(scmd); > > if (ioc->pci_error_recovery) > > @@ -4063,13 +4070,6 @@ scsih_qcmd(struct Scsi_Host *shost, struct > > scsi_cmnd *scmd) > > if (ioc->logging_level & MPT_DEBUG_SCSI) > > scsi_print_command(scmd); > > > > - /* > > - * Lock the device for any subsequent command until command > > is > > - * done. > > - */ > > - if (ata_12_16_cmd(scmd)) > > - scsi_internal_device_block(scmd->device); > > - > > sas_device_priv_data = scmd->device->hostdata; > > if (!sas_device_priv_data || !sas_device_priv_data > > ->sas_target) { > > scmd->result = DID_NO_CONNECT << 16; > > @@ -4083,6 +4083,19 @@ scsih_qcmd(struct Scsi_Host *shost, struct > > scsi_cmnd *scmd) > > return 0; > > } > > > > + /* > > + * Bug work around for firmware SATL handling. The loop > > + * is based on atomic operations and ensures consistency > > + * since we're lockless at this point > > + */ > > + do { > > + if (sas_device_priv_data->ata_command_pending) { > > + scmd->result = SAM_STAT_BUSY; > > + scmd->scsi_done(scmd); > > + return 0; > > + } > > + } while (_scsih_set_satl_pending(scmd, true)); > > + > > [Sreekanth] Just for readability purpose, can use use "if > (test_bit(0, > &sas_device_priv_data->ata_command_pending)" > instead of "if (sas_device_priv_data->ata_command_pending)". > Since while setting & clearing the bit we are using atomic bit > operations. I don't see any issue functionality wise. It's taste I suppose. I like the idea of exposing a true or false value that can be read but which uses bitops under the cover to ensure atomicity. The clincher for why not is probably that if you want another go around, I'm just about to get on a 'plane, so it won't get to it for a while and Linus will likely revert the other patch if we don't get a fix in before -rc4 James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
>>>>> "Christoph" == Christoph Hellwig <hch@lst.de> writes: Christoph> On Tue, Jan 17, 2017 at 07:43:51PM +0530, Sreekanth Reddy wrote: >> [Sreekanth] Just for readability purpose, can use use "if >> (test_bit(0, &sas_device_priv_data->ata_command_pending)" instead of >> "if (sas_device_priv_data->ata_command_pending)". Since while >> setting & clearing the bit we are using atomic bit operations. I >> don't see any issue functionality wise. Christoph> I agree. Also while we're into nitpicking - it would be good Christoph> to give bit 0 of the bitmap a name instead of hardcoding the Christoph> 0. I tweaked the test case. We can name the bit later if more flags are needed (and in that case the ata_command_pending would need to get renamed too). In any case. This issue has taken waaay too long to get resolved so the patch is now queued up in 4.10/scsi-fixes. Thanks everyone!
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h index 394fe13..dcb33f4 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_base.h +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h @@ -393,6 +393,7 @@ struct MPT3SAS_TARGET { * @eedp_enable: eedp support enable bit * @eedp_type: 0(type_1), 1(type_2), 2(type_3) * @eedp_block_length: block size + * @ata_command_pending: SATL passthrough outstanding for device */ struct MPT3SAS_DEVICE { struct MPT3SAS_TARGET *sas_target; @@ -404,6 +405,17 @@ struct MPT3SAS_DEVICE { u8 ignore_delay_remove; /* Iopriority Command Handling */ u8 ncq_prio_enable; + /* + * Bug workaround for SATL handling: the mpt2/3sas firmware + * doesn't return BUSY or TASK_SET_FULL for subsequent + * commands while a SATL pass through is in operation as the + * spec requires, it simply does nothing with them until the + * pass through completes, causing them possibly to timeout if + * the passthrough is a long executing command (like format or + * secure erase). This variable allows us to do the right + * thing while a SATL command is pending. + */ + unsigned long ata_command_pending; }; diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c index b5c966e..830e2c1 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c @@ -3899,9 +3899,18 @@ _scsih_temp_threshold_events(struct MPT3SAS_ADAPTER *ioc, } } -static inline bool ata_12_16_cmd(struct scsi_cmnd *scmd) +static int _scsih_set_satl_pending(struct scsi_cmnd *scmd, bool pending) { - return (scmd->cmnd[0] == ATA_12 || scmd->cmnd[0] == ATA_16); + struct MPT3SAS_DEVICE *priv = scmd->device->hostdata; + + if (scmd->cmnd[0] != ATA_12 && scmd->cmnd[0] != ATA_16) + return 0; + + if (pending) + return test_and_set_bit(0, &priv->ata_command_pending); + + clear_bit(0, &priv->ata_command_pending); + return 0; } /** @@ -3925,9 +3934,7 @@ _scsih_flush_running_cmds(struct MPT3SAS_ADAPTER *ioc) if (!scmd) continue; count++; - if (ata_12_16_cmd(scmd)) - scsi_internal_device_unblock(scmd->device, - SDEV_RUNNING); + _scsih_set_satl_pending(scmd, false); mpt3sas_base_free_smid(ioc, smid); scsi_dma_unmap(scmd); if (ioc->pci_error_recovery) @@ -4063,13 +4070,6 @@ scsih_qcmd(struct Scsi_Host *shost, struct scsi_cmnd *scmd) if (ioc->logging_level & MPT_DEBUG_SCSI) scsi_print_command(scmd); - /* - * Lock the device for any subsequent command until command is - * done. - */ - if (ata_12_16_cmd(scmd)) - scsi_internal_device_block(scmd->device); - sas_device_priv_data = scmd->device->hostdata; if (!sas_device_priv_data || !sas_device_priv_data->sas_target) { scmd->result = DID_NO_CONNECT << 16; @@ -4083,6 +4083,19 @@ scsih_qcmd(struct Scsi_Host *shost, struct scsi_cmnd *scmd) return 0; } + /* + * Bug work around for firmware SATL handling. The loop + * is based on atomic operations and ensures consistency + * since we're lockless at this point + */ + do { + if (sas_device_priv_data->ata_command_pending) { + scmd->result = SAM_STAT_BUSY; + scmd->scsi_done(scmd); + return 0; + } + } while (_scsih_set_satl_pending(scmd, true)); + sas_target_priv_data = sas_device_priv_data->sas_target; /* invalid device handle */ @@ -4650,8 +4663,7 @@ _scsih_io_done(struct MPT3SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply) if (scmd == NULL) return 1; - if (ata_12_16_cmd(scmd)) - scsi_internal_device_unblock(scmd->device, SDEV_RUNNING); + _scsih_set_satl_pending(scmd, false); mpi_request = mpt3sas_base_get_msg_frame(ioc, smid);