From 1fe2ddca751bb1042d6a8e447604ba16879773f5 Mon Sep 17 00:00:00 2001
From: Frede H <fh@uex.dk>
Date: Fri, 13 Sep 2024 15:07:11 +0200
Subject: [PATCH] Added kernel minor to the factor

Only kernels above 6.1 supports strict_limit and max_bytes
---
 PKGBUILD      |  4 ++--
 udev-usb-sync | 12 +++++++-----
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/PKGBUILD b/PKGBUILD
index 24cfbc8..4522c14 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -1,7 +1,7 @@
 # Maintainer: root.nix.dk
 pkgname='udev-usb-sync'
-pkgver=0.9
-pkgrel=3
+pkgver=0.10
+pkgrel=1
 pkgdesc='Fine tune write cache and impose buffer limits when USB storage device is plugged'
 arch=('any')
 url='https://codeberg.org/wonky/udev-usb-sync'
diff --git a/udev-usb-sync b/udev-usb-sync
index 46a1df2..2987613 100755
--- a/udev-usb-sync
+++ b/udev-usb-sync
@@ -42,21 +42,23 @@ CONFIG='/etc/udev-usb-sync/udev-usb-sync.conf'
 BLOCKDEVICE="$1"
 SPEED="$2"
 KERNEL_MAJOR_VERSION=$(uname -r | awk -F'.' '{print $1}')
+KERNEL_MINOR_VERSION=$(uname -r | awk -F'.' '{print $2}')
 
 # disable write cache for device if possible
-[[ -n $(which hdparm) ]] && $(which hdparm) -W 0 /dev/$BLOCKDEVICE
+[[ -n $(which hdparm) ]] && $(which hdparm) -W 0 /dev/$BLOCKDEVICE > /dev/null
 
-if [[ $KERNEL_MAJOR_VERSION -le 5 ]]; then
+if [[ $KERNEL_MAJOR_VERSION -le 6 ]]; then
    # the following rules is introduced with kernel 2.6
    # https://docs.kernel.org/admin-guide/abi-testing.html#abi-sys-class-bdi-bdi-max-ratio
-
    # 1% of available RAM ->  8046522kB -> 80.465kB -> 80MB
    echo 1 > /sys/block/$BLOCKDEVICE/bdi/max_ratio
-elif [[ $KERNEL_MAJOR_VERSION -ge 6 ]]; then
-    # the following rules is introduced with kernel 6.1
+elif [[ $KERNEL_MAJOR_VERSION -ge 6 ]] && [[ $KERNEL_MINOR_VERSION -ge 2 ]]; then
+    # the following rules is introduced with kernel 6.2
     # https://docs.kernel.org/admin-guide/abi-testing.html#abi-sys-class-bdi-bdi-strict-limit
     # https://docs.kernel.org/admin-guide/abi-testing.html#abi-sys-class-bdi-bdi-max-bytes
 
+    # Turning strictlimit on has no visible effect if max_ratio is equal to 100%.
+    echo 50 > /sys/block/$BLOCKDEVICE/bdi/max_ratio
     # apply strict limit
     echo 1 > /sys/block/$BLOCKDEVICE/bdi/strict_limit