user/sven/linux.git/include/linux/libata.h, branch v6.4.9

ata: libata-scsi: Avoid deadlock on rescan after device resume

2023-06-18T03:00:49Z

When an ATA port is resumed from sleep, the port is reset and a power management request issued to libata EH to reset the port and rescanning the device(s) attached to the port. Device rescanning is done by scheduling an ata_scsi_dev_rescan() work, which will execute scsi_rescan_device(). However, scsi_rescan_device() takes the generic device lock, which is also taken by dpm_resume() when the SCSI device is resumed as well. If a device rescan execution starts before the completion of the SCSI device resume, the rcu locking used to refresh the cached VPD pages of the device, combined with the generic device locking from scsi_rescan_device() and from dpm_resume() can cause a deadlock. Avoid this situation by changing struct ata_port scsi_rescan_task to be a delayed work instead of a simple work_struct. ata_scsi_dev_rescan() is modified to check if the SCSI device associated with the ATA device that must be rescanned is not suspended. If the SCSI device is still suspended, ata_scsi_dev_rescan() returns early and reschedule itself for execution after an arbitrary delay of 5ms. Reported-by: Kai-Heng Feng Reported-by: Joe Breuer Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217530 Fixes: a19a93e4c6a9 ("scsi: core: pm: Rely on the device driver core for async power management") Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Tested-by: Kai-Heng Feng Tested-by: Joe Breuer

scsi: ata: Declare SCSI host templates const

2023-03-24T23:19:19Z

Make it explicit that ATA host templates are not modified. Reviewed-by: Linus Walleij Acked-by: Damien Le Moal Reviewed-by: Serge Semin (for DWC AHCI SATA) Reviewed-by: John Garry Reviewed-by: Jon Hunter (for Tegra) Cc: Christoph Hellwig Cc: Ming Lei Cc: Hannes Reinecke Cc: John Garry Cc: Mike Christie Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20230322195515.1267197-5-bvanassche@acm.org Signed-off-by: Martin K. Petersen

ata: libata: cleanup fua support detection

2023-01-13T22:32:42Z

Move the detection of a device FUA support from ata_scsiop_mode_sense()/ata_dev_supports_fua() to device scan time in ata_dev_configure(). The function ata_dev_config_fua() is introduced to detect if a device supports FUA and this support is indicated using the new device flag ATA_DFLAG_FUA. In order to blacklist known buggy devices, the horkage flag ATA_HORKAGE_NO_FUA is introduced. Similarly to other horkage flags, the libata.force= arguments "fua" and "nofua" are also introduced to allow a user to control this horkage flag through the "force" libata module parameter. The ATA_DFLAG_FUA device flag is set only and only if all the following conditions are met: * libata.fua module parameter is set to 1 * The device supports the WRITE DMA FUA EXT command, * The device is not marked with the ATA_HORKAGE_NO_FUA flag, either from the blacklist or set by the user with libata.force=nofua * The device supports NCQ (while this is not mandated by the standards, this restriction is introduced to avoid problems with older non-NCQ devices). Enabling or diabling libata FUA support for all devices can now also be done using the "force=[no]fua" module parameter when libata.fua is set to 1. Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Chaitanya Kulkarni Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Niklas Cassel

ata: libata: Introduce ata_ncq_supported()

2023-01-13T22:32:42Z

Introduce the inline helper function ata_ncq_supported() to test if a device supports NCQ commands. The function ata_ncq_enabled() is also rewritten using this new helper function. Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Chaitanya Kulkarni Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Niklas Cassel

ata: libata: move NCQ related ATA_DFLAGs

2023-01-04T04:39:38Z

ata_dev_configure() starts off by clearing all flags in ATA_DFLAG_CFG_MASK: dev->flags &= ~ATA_DFLAG_CFG_MASK; ata_dev_configure() then calls ata_dev_config_lba() which calls ata_dev_config_ncq(). ata_dev_config_ncq() will set the correct ATA_DFLAGs depending on what is actually supported. Since these flags are set by ata_dev_configure(), they should be in ATA_DFLAG_CFG_MASK and not in ATA_DFLAG_INIT_MASK. ATA_DFLAG_NCQ_PRIO_ENABLED is set via sysfs, is should therefore not be in ATA_DFLAG_CFG_MASK. It also cannot be in ATA_DFLAG_INIT_MASK, because ata_eh_schedule_probe() calls ata_dev_init(), which will clear all flags in ATA_DFLAG_INIT_MASK. This means that ATA_DFLAG_NCQ_PRIO_ENABLED (the value the user sets via sysfs) would get silently cleared if ata_eh_schedule_probe() is called. While that should only happen in certain circumstances, it still doesn't seem right that it can get silently cleared. (ata_dev_config_ncq_prio() will still clear the ATA_DFLAG_NCQ_PRIO_ENABLED flag if ATA_DFLAG_NCQ_PRIO is suddenly no longer supported after a revalidation.) Because of this, move ATA_DFLAG_NCQ_PRIO_ENABLED to be outside of both ATA_DFLAG_CFG_MASK and ATA_DFLAG_INIT_MASK. Signed-off-by: Niklas Cassel Signed-off-by: Damien Le Moal

ata: libata: read the shared status for successful NCQ commands once

2023-01-04T04:38:14Z

Currently, the status is being read for each QC, inside ata_qc_complete(), which means that QCs being completed by ata_qc_complete_multiple() (i.e. multiple QCs completed during a single interrupt), can have different status and error bits set. This is because the FIS Receive Area will get updated as soon as the HBA receives a new FIS from the device in the NCQ case. Here is an example of the problem: ata14.00: ata_qc_complete_multiple: done_mask: 0x180000 qc tag: 19 cmd: 0x61 flags: 0x11b err_mask: 0x0 tf->status: 0x40 qc tag: 20 cmd: 0x61 flags: 0x11b err_mask: 0x0 tf->status: 0x43 A print in ata_qc_complete_multiple(), shows that done_mask is: 0x180000 which means that tag 19 and 20 were completed. Another print in ata_qc_complete(), after the call to fill_result_tf(), shows that tag 19 and 20 have different status values, even though they were completed in the same ata_qc_complete_multiple() call. If PMP is not enabled, simply read the status and error once, before calling ata_qc_complete() for each QC. Without PMP, we know that all QCs must share the same status and error values. If PMP is enabled, we also read the status before calling ata_qc_complete(), however, we still read the status for each QC, since the QCs can belong to different PMP links (which means that the QCs does not necessarily share the same status and error values). Do all this by introducing the new port operation .qc_ncq_fill_rtf. If set, this operation is called in ata_qc_complete_multiple() to set the result tf for all completed QCs signaled by the last SDB FIS received. QCs that have their result tf filled are marked with the new flag ATA_QCFLAG_RTF_FILLED so that any later execution of the qc_fill_rtf port operation does nothing (e.g. when called from ata_qc_complete()). Co-developed-by: Damien Le Moal Signed-off-by: Damien Le Moal Signed-off-by: Niklas Cassel

ata: libata: simplify qc_fill_rtf port operation interface

2023-01-04T04:37:45Z

The boolean return value of the qc_fill_rtf operation is used nowhere. Simplify this operation interface by making it a void function. All drivers defining this operation are also updated. Signed-off-by: Damien Le Moal Signed-off-by: Niklas Cassel Reviewed-by: John Garry

ata: scsi: rename flag ATA_QCFLAG_FAILED to ATA_QCFLAG_EH

2023-01-04T04:36:26Z

The name ATA_QCFLAG_FAILED is misleading since it does not mean that a QC completed in error, or that it didn't complete at all. It means that libata decided to schedule EH for the QC, so the QC is now owned by the libata error handler (EH). The normal execution path is responsible for not accessing a QC owned by EH. libata core enforces the rule by returning NULL from ata_qc_from_tag() for QCs owned by EH. It is quite easy to mistake that a QC marked with ATA_QCFLAG_FAILED was an error. However, a QC that was actually an error is instead indicated by having qc->err_mask set. E.g. when we have a NCQ error, we abort all QCs, which currently will mark all QCs as ATA_QCFLAG_FAILED. However, it will only be a single QC that is an error (i.e. has qc->err_mask set). Rename ATA_QCFLAG_FAILED to ATA_QCFLAG_EH to more clearly highlight that this flag simply means that a QC is now owned by EH. This new name will not mislead to think that the QC was an error (which is instead indicated by having qc->err_mask set). This also makes it more obvious that the EH code skips all QCs that do not have ATA_QCFLAG_EH set (rather than ATA_QCFLAG_FAILED), since the EH code should simply only care about QCs that are owned by EH itself. Signed-off-by: Niklas Cassel Reviewed-by: John Garry Signed-off-by: Damien Le Moal

ata: libata-sff: kill unused ata_sff_busy_sleep()

2022-11-11T08:20:26Z

Nobody seems to call ata_sff_busy_sleep(), so we can get rid of it... Signed-off-by: Sergey Shtylyov Signed-off-by: Damien Le Moal

ata: add ata_port_is_frozen() helper

2022-10-18T04:53:24Z

At the request of the libata maintainer, introduce a ata_port_is_frozen() helper function. Signed-off-by: Niklas Cassel Signed-off-by: Damien Le Moal