Xen traditionally allows customizing guest behavior by passing arguments
to the VM kernel via the kernel command line. This is no longer possible
when using GRUB with Xen, as the kernel command line is decided by the
GRUB configuration file within the guest, not data passed to the guest
by Xen.
To work around this limitation, enable GRUB to parse a command line
passed to it by Xen, and expose data from the command line to the GRUB
configuration as environment variables. These variables can be used in
the GRUB configuration for any desired purpose, such as extending the
kernel command line passed to the guest. The command line format is
inspired by the Linux kernel's command line format.
To reduce the risk of misuse, abuse, or accidents in production, the
command line will only be parsed if it consists entirely of 7-bit ASCII
characters, only alphabetical characters and underscores are permitted
in variable names, and all variable names must start with the string
"xen_grub_env_". This also allows room for expanding the command line
arguments accepted by GRUB in the future, should other arguments end up
becoming desirable in the future.
Signed-off-by: Aaron Rainbolt <arraybolt3@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Add all usable memory regions to grub memory management and add the
needed mmap iterate code, which will be used by grub core (e.g.
grub-core/lib/relocator.c or grub-core/mmap/mmap.c).
As we are running in 32-bit mode don't add memory above 4GB.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Hans van Kranenburg <hans@knorrie.org>
Initialize the needed Xen specific data. This is:
- the Xen start of day page containing the console and Xenstore ring
page PFN and event channel
- the grant table
- the shared info page
Write back the possibly modified memory map to the hypervisor in case
the guest is reading it from there again.
Set the RSDP address for the guest from the start_info page passed
as boot parameter.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Tested-by: Hans van Kranenburg <hans@knorrie.org>
Retrieve the memory map from the hypervisor and normalize it to contain
no overlapping entries and to be sorted by address.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Hans van Kranenburg <hans@knorrie.org>
Add the needed code to setup the hypercall page for calling into the
Xen hypervisor.
Import the XEN_HVM_DEBUGCONS_IOPORT define from Xen unstable into
include/xen/arch-x86/xen.h
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Hans van Kranenburg <hans@knorrie.org>
Add the hooks to current code needed for Xen PVH. They will be filled
with code later when the related functionality is being added.
loader/i386/linux.c needs to include machine/kernel.h now as it needs
to get GRUB_KERNEL_USE_RSDP_ADDR from there. This in turn requires to
add an empty kernel.h header for some i386 platforms (efi, coreboot,
ieee1275, xen) and for x86_64 efi.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Hans van Kranenburg <hans@knorrie.org>
