[PATCH] USB HardDisk Booting 2.4.20

Wesley Wright
2003-01-30T17:15:11Z

[-- Attachment #1: Type: text/plain, Size: 825 bytes --]

I recently acquired a USB HardDisk and it seems that the drivers for USB
load after attempts to mount the root partition. I saw one patch that
just put the root mount code into an endless loop, but didn't like this
solution.

What I've done here is add another kernel config option which indicates
if you have a USB device you with to boot. If you do then it changes
the module_init's in drivers/usb/usb.c and drivers/usb/storage/usb.c to
__initcall's. The config option is only enabled when you've selected
"Y" for the USB Mass Storage Device.

My tests show that it seems to work, and I haven't noticed any odd side
affects by initcall-ing the usb devices (concern over this topic is why
I enabled it for static USB MSD only).

Does this seem a reasonable solution, or does anyone have something more
elegant?

-- Wes

[-- Attachment #2: README --]
[-- Type: text/x-readme, Size: 334 bytes --]

This patch adds a config option that, if static USB Mass Storage is selected,
enabled telling the kernel that you have a bootable USB device (like a Hard
Disk). It will then try to load the USB device and Mass Storage code
earlier in the boot process so you can mount root USB devices.

Wesley Wright
wewright@verizonmail.com

[-- Attachment #3: usbboot-2.4.20.patch --]
[-- Type: text/x-patch, Size: 6085 bytes --]

diff -urN linux-2.4.20/arch/alpha/defconfig linux-2.4.20-usbboot/arch/alpha/defconfig
--- linux-2.4.20/arch/alpha/defconfig 2001-11-19 18:19:42.000000000 -0500
+++ linux-2.4.20-usbboot/arch/alpha/defconfig 2003-01-30 12:18:13.000000000 -0500
@@ -690,6 +690,7 @@
# CONFIG_USB_BLUETOOTH is not set
# CONFIG_USB_STORAGE is not set
# CONFIG_USB_STORAGE_DEBUG is not set
+# CONFIG_USB_STORAGE_BOOT is not set
# CONFIG_USB_STORAGE_DATAFAB is not set
# CONFIG_USB_STORAGE_FREECOM is not set
# CONFIG_USB_STORAGE_ISD200 is not set
diff -urN linux-2.4.20/arch/i386/defconfig linux-2.4.20-usbboot/arch/i386/defconfig
--- linux-2.4.20/arch/i386/defconfig 2002-11-28 18:53:09.000000000 -0500
+++ linux-2.4.20-usbboot/arch/i386/defconfig 2003-01-30 12:18:13.000000000 -0500
@@ -776,6 +776,7 @@
# CONFIG_USB_BLUETOOTH is not set
CONFIG_USB_STORAGE=y
# CONFIG_USB_STORAGE_DEBUG is not set
+# CONFIG_USB_STORAGE_BOOT is not set
# CONFIG_USB_STORAGE_DATAFAB is not set
# CONFIG_USB_STORAGE_FREECOM is not set
# CONFIG_USB_STORAGE_ISD200 is not set
diff -urN linux-2.4.20/arch/ia64/defconfig linux-2.4.20-usbboot/arch/ia64/defconfig
--- linux-2.4.20/arch/ia64/defconfig 2002-11-28 18:53:09.000000000 -0500
+++ linux-2.4.20-usbboot/arch/ia64/defconfig 2003-01-30 12:18:13.000000000 -0500
@@ -848,6 +848,7 @@
# CONFIG_USB_BLUETOOTH is not set
# CONFIG_USB_STORAGE is not set
# CONFIG_USB_STORAGE_DEBUG is not set
+# CONFIG_USB_STORAGE_BOOT is not set
# CONFIG_USB_STORAGE_DATAFAB is not set
# CONFIG_USB_STORAGE_FREECOM is not set
# CONFIG_USB_STORAGE_ISD200 is not set
diff -urN linux-2.4.20/arch/parisc/defconfig linux-2.4.20-usbboot/arch/parisc/defconfig
--- linux-2.4.20/arch/parisc/defconfig 2002-11-28 18:53:10.000000000 -0500
+++ linux-2.4.20-usbboot/arch/parisc/defconfig 2003-01-30 12:18:13.000000000 -0500
@@ -772,6 +772,7 @@
# CONFIG_USB_BLUETOOTH is not set
# CONFIG_USB_STORAGE is not set
# CONFIG_USB_STORAGE_DEBUG is not set
+# CONFIG_USB_STORAGE_BOOT is not set
# CONFIG_USB_STORAGE_DATAFAB is not set
# CONFIG_USB_STORAGE_FREECOM is not set
# CONFIG_USB_STORAGE_ISD200 is not set
diff -urN linux-2.4.20/arch/ppc/defconfig linux-2.4.20-usbboot/arch/ppc/defconfig
--- linux-2.4.20/arch/ppc/defconfig 2002-11-28 18:53:11.000000000 -0500
+++ linux-2.4.20-usbboot/arch/ppc/defconfig 2003-01-30 12:18:13.000000000 -0500
@@ -934,6 +934,7 @@
# CONFIG_USB_MIDI is not set
# CONFIG_USB_STORAGE is not set
# CONFIG_USB_STORAGE_DEBUG is not set
+# CONFIG_USB_STORAGE_BOOT is not set
# CONFIG_USB_STORAGE_DATAFAB is not set
# CONFIG_USB_STORAGE_FREECOM is not set
# CONFIG_USB_STORAGE_ISD200 is not set
diff -urN linux-2.4.20/arch/sparc64/defconfig linux-2.4.20-usbboot/arch/sparc64/defconfig
--- linux-2.4.20/arch/sparc64/defconfig 2002-11-28 18:53:12.000000000 -0500
+++ linux-2.4.20-usbboot/arch/sparc64/defconfig 2003-01-30 12:18:13.000000000 -0500
@@ -779,6 +779,7 @@
CONFIG_USB_MIDI=m
CONFIG_USB_STORAGE=m
# CONFIG_USB_STORAGE_DEBUG is not set
+# CONFIG_USB_STORAGE_BOOT is not set
# CONFIG_USB_STORAGE_DATAFAB is not set
CONFIG_USB_STORAGE_FREECOM=y
CONFIG_USB_STORAGE_ISD200=y
diff -urN linux-2.4.20/Documentation/Configure.help linux-2.4.20-usbboot/Documentation/Configure.help
--- linux-2.4.20/Documentation/Configure.help 2002-11-28 18:53:08.000000000 -0500
+++ linux-2.4.20-usbboot/Documentation/Configure.help 2003-01-30 12:18:13.000000000 -0500
@@ -24374,6 +24374,13 @@
brave people. System crashes and other bad things are likely to occur if
you use this driver. If in doubt, select N.

+USB Boot Device Support
+CONFIG_USB_STORAGE_BOOT
+ This option will load the USB controller and USB storage device drivers
+ earlier in the boot process. This enables systems which want to boot
+ off of a USB device (like a USB HardDisk) to detect the device before
+ trying to mount root, thus avoiding a kernel panic.
+
Winbond W83977AF IrDA Device Driver
CONFIG_WINBOND_FIR
Say Y here if you want to build IrDA support for the Winbond
diff -urN linux-2.4.20/drivers/usb/Config.in linux-2.4.20-usbboot/drivers/usb/Config.in
--- linux-2.4.20/drivers/usb/Config.in 2002-11-28 18:53:14.000000000 -0500
+++ linux-2.4.20-usbboot/drivers/usb/Config.in 2003-01-30 12:18:13.000000000 -0500
@@ -39,6 +39,9 @@
fi
dep_tristate ' USB Mass Storage support' CONFIG_USB_STORAGE $CONFIG_USB $CONFIG_SCSI
dep_mbool ' USB Mass Storage verbose debug' CONFIG_USB_STORAGE_DEBUG $CONFIG_USB_STORAGE
+ if [ "$CONFIG_USB_STORAGE" = "y" ] ; then
+ dep_mbool ' USB Boot Device Support' CONFIG_USB_STORAGE_BOOT $CONFIG_USB_STORAGE
+ fi
dep_mbool ' Datafab MDCFE-B Compact Flash Reader support' CONFIG_USB_STORAGE_DATAFAB $CONFIG_USB_STORAGE $CONFIG_EXPERIMENTAL
dep_mbool ' Freecom USB/ATAPI Bridge support' CONFIG_USB_STORAGE_FREECOM $CONFIG_USB_STORAGE
dep_mbool ' ISD-200 USB/ATA Bridge support' CONFIG_USB_STORAGE_ISD200 $CONFIG_USB_STORAGE
diff -urN linux-2.4.20/drivers/usb/storage/usb.c linux-2.4.20-usbboot/drivers/usb/storage/usb.c
--- linux-2.4.20/drivers/usb/storage/usb.c 2002-11-28 18:53:15.000000000 -0500
+++ linux-2.4.20-usbboot/drivers/usb/storage/usb.c 2003-01-30 12:18:13.000000000 -0500
@@ -1164,5 +1164,10 @@
}
}

-module_init(usb_stor_init);
-module_exit(usb_stor_exit);
+#ifdef CONFIG_USB_STORAGE_BOOT
+ __initcall(usb_stor_init);
+#else
+ module_init(usb_stor_init);
+ module_exit(usb_stor_exit);
+#endif
+
diff -urN linux-2.4.20/drivers/usb/usb.c linux-2.4.20-usbboot/drivers/usb/usb.c
--- linux-2.4.20/drivers/usb/usb.c 2002-11-28 18:53:15.000000000 -0500
+++ linux-2.4.20-usbboot/drivers/usb/usb.c 2003-01-30 12:18:13.000000000 -0500
@@ -2373,8 +2373,12 @@
usb_hub_cleanup();
}

-module_init(usb_init);
-module_exit(usb_exit);
+#ifdef CONFIG_USB_STORAGE_BOOT
+ __initcall(usb_init);
+#else
+ module_init(usb_init);
+ module_exit(usb_exit);
+#endif

/*
* USB may be built into the kernel or be built as modules.