From e913ca7d16d70b75367ff56a3b201980501d542c Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Thu, 4 Oct 2012 09:57:31 +0100 Subject: efivarfs: Add documentation for the EFI variable filesystem Signed-off-by: Matt Fleming --- Documentation/filesystems/efivarfs.txt | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) create mode 100644 Documentation/filesystems/efivarfs.txt (limited to 'Documentation/filesystems/efivarfs.txt') diff --git a/Documentation/filesystems/efivarfs.txt b/Documentation/filesystems/efivarfs.txt new file mode 100644 index 000000000000..c477af086e65 --- /dev/null +++ b/Documentation/filesystems/efivarfs.txt @@ -0,0 +1,16 @@ + +efivarfs - a (U)EFI variable filesystem + +The efivarfs filesystem was created to address the shortcomings of +using entries in sysfs to maintain EFI variables. The old sysfs EFI +variables code only supported variables of up to 1024 bytes. This +limitation existed in version 0.99 of the EFI specification, but was +removed before any full releases. Since variables can now be larger +than a single page, sysfs isn't the best interface for this. + +Variables can be created, deleted and modified with the efivarfs +filesystem. + +efivarfs is typically mounted like this, + + mount -t efivarfs none /sys/firmware/efi/efivars -- cgit