Fix SSD TRIM on UGREEN UASP USB SATA adapter/enclosure

I've finally figured out how to fix SSD TRIM on the newer UGREEN USB SATA adapter and enclosure, both on my machine and Raspberry Pi-s!

We need to:

1. Set 'unmap' on /sys/block/sda/device/scsi_disk/0:0:0:0/provisioning_mode (the standard fix)
2. Set '2147450880' on /sys/block/sda/queue/discard_max_bytes

Without the 2nd fix, fstrim would only work on small partitions.

Permanent fix via UDEV Rules

Add these udev rules to /etc/udev/rules.d/99-ugreen-sata-adapter-trim-enable.rules:

# UGREEN SATA USB adapter cable - ASMedia Technology Inc. Ugreen Storage Device
ACTION=="add|change", ATTRS{idVendor}=="174c", ATTRS{idProduct}=="225c", SUBSYSTEM=="scsi_disk", ATTR{provisioning_mode}="unmap"
ACTION=="add|change", ATTRS{idVendor}=="174c", ATTRS{idProduct}=="225c", SUBSYSTEM=="block", ATTR{queue/discard_max_bytes}="2147450880"

# UGREEN SATA Enclosure - ASMedia Technology Inc. ASM1153 SATA 3Gb/s bridge
ACTION=="add|change", ATTRS{idVendor}=="174c", ATTRS{idProduct}=="1153", SUBSYSTEM=="scsi_disk", ATTR{provisioning_mode}="unmap"
ACTION=="add|change", ATTRS{idVendor}=="174c", ATTRS{idProduct}=="1153", SUBSYSTEM=="block", ATTR{queue/discard_max_bytes}="2147450880"

💡: You may need to change idProduct to your own - check lsusb.

e.g. Here're mine:

# `lsusb` output:
...
Bus 002 Device 034: ID 174c:225c ASMedia Technology Inc. Ugreen Storage Device
...
Bus 002 Device 041: ID 174c:1153 ASMedia Technology Inc. ASM1153 SATA 3Gb/s bridge

Where did 2147450880 come from?

It seems fstrim can still fail on large partitions, with the default discard_max_bytes value too big (4294966784) - we need to set it to the maximum the adapter can handle.

2147450880 is this maximum in my case, calculated from 2 attributes from the adapter:

1. Maximum unmap LBA count (from sg_vpd)
2. Logical block length (from sg_readcap)

Here's a small snippet to show yours:

sudo su -
apt install sg3-utils

# Device to check
device=sdh
# e.g. lba_count=4194240
lba_count=$(sg_vpd --all /dev/$device|grep 'Maximum unmap LBA count'|grep -Po '(?<=: )(.*)(?=$)')
# e.g. block_length=512
block_length=$(sg_readcap --long /dev/$device|grep 'Logical block length'|grep -Po '(?<=\=)(.*)(?= bytes)')
# e.g. 2147450880
echo $(( $lba_count * $block_length ))

Symptoms addressed by fix

This fix will be relevant to you if you encounter these errors:

# fstrim -v /
fstrim: /: the discard operation is not supported
fstrim: /: FITRIM ioctl failed: Operation not permitted

And in /var/log/syslog / journalctl:

Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#12 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#12 Sense Key : Illegal Request [current] 
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#12 Add. Sense: Invalid field in cdb
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#12 CDB: Unmap/Read sub-channel 42 00 00 00 00 00 00 00 18 00
Sep 22 20:16:19 LINUX kernel: print_req_error: 6703 callbacks suppressed
Sep 22 20:16:19 LINUX kernel: blk_update_request: critical target error, dev sdg, sector 39667712 op 0x3:(DISCARD) flags 0x4000 phys_seg 1 prio class 0
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#13 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#13 Sense Key : Illegal Request [current] 
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#13 Add. Sense: Invalid field in cdb
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#13 CDB: Unmap/Read sub-channel 42 00 00 00 00 00 00 00 18 00
Sep 22 20:16:19 LINUX kernel: blk_update_request: critical target error, dev sdg, sector 48056312 op 0x3:(DISCARD) flags 0x4000 phys_seg 1 prio class 0
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#14 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#14 Sense Key : Illegal Request [current] 
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#14 Add. Sense: Invalid field in cdb
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#14 CDB: Unmap/Read sub-channel 42 00 00 00 00 00 00 00 18 00
Sep 22 20:16:19 LINUX kernel: blk_update_request: critical target error, dev sdg, sector 56444912 op 0x3:(DISCARD) flags 0x4000 phys_seg 1 prio class 0
Sep 22 20:16:19 LINUX kernel: blk_update_request: critical target error, dev sdg, sector 89999312 op 0x3:(DISCARD) flags 0x0 phys_seg 1 prio class 0
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#15 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#15 Sense Key : Illegal Request [current] 
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#15 Add. Sense: Invalid field in cdb
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#15 CDB: Unmap/Read sub-channel 42 00 00 00 00 00 00 00 18 00
Sep 22 20:16:19 LINUX kernel: blk_update_request: critical target error, dev sdg, sector 64833512 op 0x3:(DISCARD) flags 0x4000 phys_seg 1 prio class 0
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#16 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#16 Sense Key : Illegal Request [current] 
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#16 Add. Sense: Invalid field in cdb
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#16 CDB: Unmap/Read sub-channel 42 00 00 00 00 00 00 00 18 00
Sep 22 20:16:19 LINUX kernel: blk_update_request: critical target error, dev sdg, sector 73222112 op 0x3:(DISCARD) flags 0x4000 phys_seg 1 prio class 0
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#17 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#17 Sense Key : Illegal Request [current] 
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#17 Add. Sense: Invalid field in cdb
Sep 22 20:16:19 LINUX kernel: sd 7:0:0:0: [sdg] tag#17 CDB: Unmap/Read sub-channel 42 00 00 00 00 00 00 00 18 00
Sep 22 20:16:19 LINUX kernel: blk_update_request: critical target error, dev sdg, sector 81610712 op 0x3:(DISCARD) flags 0x4000 phys_seg 1 prio class 0
Sep 22 20:16:19 LINUX kernel: BTRFS warning (device sdg3): failed to trim 1 device(s), last error -95

Credit

This is only possible thanks to this post from Jeff Geerling (he's awesome 👍)