Speed up the 'scan then fix' use case

[g2p]

One of my diskscans (without --fix) stopped at the first error:

E: IO failed with no sense: status=2 mask=1 driver=8 msg=0 host=0 E: Error when reading at offset 123456789 size 65536 read 65536: Success E: Details: error=fatal data=full 00/00/00 E: Fatal error occurred, bailing out.

The kernel log has more info (uncorrectable sector), I don't know how much is passed to userland (not through "sense" apparently).

[13645.452988] ata6.00: exception Emask 0x0 SAct 0x800000 SErr 0x0 action 0x0 [13645.452992] ata6.00: irq_stat 0x40000008 [13645.452995] ata6.00: failed command: READ FPDMA QUEUED [13645.453000] ata6.00: cmd 60/80:b8:a9:7e:3d/00:00:82:00:00/40 tag 23 ncq 65536 in [13645.453003] ata6.00: status: { DRDY ERR } [13645.453005] ata6.00: error: { UNC } [13645.465194] ata6.00: configured for UDMA/133 [13645.465214] ata6: EH complete

I would prefer if the scan kept running in this case; this is a large disk and scanning good sectors again takes time.

Also, it would be extra helpful if --fix mode could reuse the log to start with error events and high-latency ranges. This way the total runtime for scanning then fixing could be halved.

[baruch]

What platform are you on? Linux or a BSD? What is the symlink arch/arch.c pointing to? On Linux I diskscan issues scsi commands and should get the full sense buffer so it's strange that it got no info.

I'll also take a look at why it stopped on error, I agree it should continue to test and report on the entire disk.

[baruch]

Looks like you are on Linux but for some reason the SATA driver didn't translate the error to a SCSI sense and only returned it as a driver error. Can you provide the output of lspci? This will tell me what is the SATA controller so I'll know about it.

I currently default to make any unknown error a fatal one and this stops the scan since fatal errors mean there is no reason to continue the scan (disk fully dead). I'll think about this and see what I can do.

[baruch]

Made unknown errors non-fatal, can you please test it and let me know if it works out for you?

[g2p]

Testing, will report back in a few hours.

Relevant lspci bits:

00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family SATA AHCI Controller (rev 05) (prog-if 01 [AHCI 1.0])
    Subsystem: ASUSTeK Computer Inc. P8 series motherboard
    Flags: bus master, 66MHz, medium devsel, latency 0, IRQ 46
    I/O ports at f070 [size=8]
    I/O ports at f060 [size=4]
    I/O ports at f050 [size=8]
    I/O ports at f040 [size=4]
    I/O ports at f020 [size=32]
    Memory at f6306000 (32-bit, non-prefetchable) [size=2K]
    Capabilities: [80] MSI: Enable+ Count=1/1 Maskable- 64bit-
    Capabilities: [70] Power Management version 3
    Capabilities: [a8] SATA HBA v1.0
    Capabilities: [b0] PCI Advanced Features
    Kernel driver in use: ahci

[baruch]

The SATA controller is the same one I have, though on my own disk there were no uncorrectable errors for me to see this phenomenon. It would be non-trivial to be able to test this though, will need to delve into READ LONG and WRITE LONG and hope there is an equivalent in SATA for them.

[g2p]

With this change I was able to complete the scan. Thank you.

[baruch]

Great!