於 四，2012-10-04 於 09:54 +0100，Matt Fleming 提到： > On Thu, 2012-10-04 at 10:24 +0800, Lee, Chun-Yi wrote: > > UEFI variable filesystem need a new mount point, so this patch add > > efivars kobject to efi_kobj for create a /sys/firmware/efi/efivars > > folder. > > > > Cc: Matt Fleming <matt.fleming@xxxxxxxxx> > > Cc: Jeremy Kerr <jeremy.kerr@xxxxxxxxxxxxx> > > Cc: Matthew Garrett <mjg@xxxxxxxxxx> > > Cc: H. Peter Anvin <hpa@xxxxxxxxx> > > Signed-off-by: Lee, Chun-Yi <jlee@xxxxxxxx> > > --- > > drivers/firmware/efivars.c | 11 +++++++++++ > > include/linux/efi.h | 1 + > > 2 files changed, 12 insertions(+), 0 deletions(-) > > Actually, shouldn't the new filesystem be called "efivarfs", or "efifs" > to make it more explicit that it is a filesystem? I used "efivars" because this folder generated by efivars. But, I like your suggestion for use "efivarfs", it's better then "efivars". > > We also need something in Documentation/filesystems/ describing the old > EFI variable method, why it's no longer any good, and why the new > filesystem is favoured. Does anybody have anything to add to the > following? > > diff --git a/Documentation/filesystems/00-INDEX b/Documentation/filesystems/00-INDEX > index 8c624a1..ddf5a83 100644 > --- a/Documentation/filesystems/00-INDEX > +++ b/Documentation/filesystems/00-INDEX > @@ -38,6 +38,8 @@ dnotify_test.c > - example program for dnotify > ecryptfs.txt > - docs on eCryptfs: stacked cryptographic filesystem for Linux. > +efivars.txt > + - info for the efivars filesystem. > exofs.txt > - info, usage, mount options, design about EXOFS. > ext2.txt > diff --git a/Documentation/filesystems/efivars.txt b/Documentation/filesystems/efivars.txt > new file mode 100644 > index 0000000..4350c1a > --- /dev/null > +++ b/Documentation/filesystems/efivars.txt > @@ -0,0 +1,16 @@ > + > +efivars - a (U)EFI variable filesystem > + > +The efivars 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 efivars > +filesystem. > + > +The efivars filesystem is typically mounted like this, > + > + mount -t efivars none /sys/firmware/efi/efivars > The above documentation is really good! Thanks a lot! Joey Lee -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
