Largely this involves making the logic symmetrical: for example,
not only should netfront be able to tell netback that a packet has
an empty protocol checksum field, but the reverse must also be true.
Another change is that the drivers only advertise IP checksum
offload functionality. There is currently no information
propagated across the device channel about the offset of the
protocol-specific checksum field. Therefore it is not safe to
defer checksum calculation for protocols the remote end may not
understand -- it will end up dropping having to drop the packet.
Yet another change is to allow netback to disable tx checksum
offload, just as we already could for netfront. Currently there is
no support for disabling rx checksum offload -- that would seem
to require some way of propagating the checksum-offload advertisement
(or lack of it) across the device channel, as it really ought to be
the transmitter that acts on it.
Thanks to Ian Jackson for pointing out some of the problems with
our checksum-offload handling. Several of the changes here are
due to his comments.
Signed-off-by: Keir Fraser <keir@xensource.com>
switch out of a transaction, in the few cases where it is inside one.
In order to behave properly, it is necessary for a driver to know its own
xenbus state (see changeset 9469:b3cb19d2b07f, for example). This
value is stored as xenbus_device.state and updated by xenbus_switch_state.
If xenbus_switch_state occurs within a transaction, then there is a possibility
that the transaction would be aborted, leaving the state field dangerously out
of sync with the value currently in the store.
This fixes recent problems seen whereby bringing multiple devices up at the
same time results in some devices not coming up (often all of the even-numbered
ones, because of the pattern of transaction conflict).
Signed-off-by: Ewan Mellor <ewan@xensource.com>
Define interface version in Kconfig and define it through CPPFLAGS for
C and assembly file compilation.
Add HYPERVISOR_{yield,block,shutdown} to remove direct use of sched_op
from guest code.
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
1. No longer hold xenbus_lock while taking down VCPUs
in SMP suspend path. This allows block device hotplug
to continue working and so we will not deadlock on
paging in userspace hotplug code.
2. Track xenbus and local-admin permitted cpumasks for
VCPUs to bring online. So, if a local admin takes a
CPU down, that won't surprisingly get overridden next
time the kernel interrogates xenstore.
Signed-off-by: Keir Fraser <keir@xensource.com>
to GPL modules. Rename pte_page parameter to pmd_page (following the
Linux idiom). apply_to_pte_range() should take the pte spinlock.
Signed-off-by: Keir Fraser <keir@xensource.com>
1. Make it clear in all dual-licensed files that the
license when distributed with Linux is GPLv2.
2. Add MODULE_LICENSE(dual) in a few places.
3. Change many of our EXPORT_SYMBOL() decls to EXPORT_SYMBOL_GPL().
This is the preference of the Linux maintainers, and avoids any
trouble down the road if our EXPORT_SYMBOL'ed functions use Linux
internal interfaces that are GPL only.
Signed-off-by: Keir Fraser <keir@xensource.com>
module has a tri-state configuration so it can be a loadable module.
Views the hypervisor as hardware device, uses sysfs as a scripting
interface for user space tools that need these attributes.
Some user space apps, particularly for systems management, need to
know if their kernel is running in a virtual machine and if so in
what type of virtual machine. This property is contained in the
file /sys/hypervisor/type.
The file hypervisor_sysfs.c creates a generic hypervisor subsystem
that can be linked to by any hypervisor. The file xen_sysfs.c exports
the xen-specific attributes.
Signed-off-by: Mike D. Day <ncmike@us.ibm.com>
legacy hypercall in that it takes a pointer to a block of extra arguments
rather than an opaque unsigned long. The old hypercall still exists, for
backwards compatibility.
The new hypercall supports new sub-command SCHEDOP_poll, which can be used to
wait on a set of event-channel ports with an optional timeout. This is exported
in XenLinux as HYPERVISOR_poll, and used in the pcifront driver to wait on a
response from the pciback driver.
Can also be used for debuggers. :-)
Signed-off-by: Keir Fraser <keir@xensource.com>
Signed-off-by: John Levon <john.levon@sun.com>
the low half before the high half. Otherwise the compiler may reorder the writes
and validation in Xen will fail.
From: Jan Beulich
Signed-off-by: Keir Fraser <keir@xensource.com>
Instead of putting the page outside of the guests pseudo-physical address
space, we put it next to the other pages filled by the domain builder,
such that the page is already mapped in the initial pagetables and/or a
lowmem-type memory mapping.
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
at the local end of the xenbus connection (i.e. that value that is passed
through xenbus_switch_state). This means that xenbus_probe can wait for all
the boot devices to become ready without having to hurt the store.
Also, fix this probing -- previously, the wrong value was being returned by
all_devices_ready_, so this polling would only have waited for one device.
Signed-off-by: Ewan Mellor <ewan@xensource.com>
- machine_specific_memory_setup() was unused on x86-64
- machine_specific_modify_cpu_capabilities() must not be __init (for CPU hotplug)
- machine_specific_modify_cpu_capabilities() should be called in similar ways on 32- and 64-bits
From: Jan Beulich <JBeulich@novell.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Add comments in public header version.h to explain what all the different
feature flags mean. Add a new flag XENFEAT_pae_pgdir_above_4gb to inform the guest
that its PAE page directories do not need to conform to the usual hardware
restriction.
Signed-off-by: Keir Fraser <keir@xensource.com>
To support this we give kernel GDT entries DPL=0 and use kernel
segment selectors with RPL=0. Xen will crunch these to ring 1 when
they are passed in. When a segment selector is used directly or placed
in a stack frame the guest OS is reponsible for crunching the RPL.
Signed-off-by: Ian Campbell <Ian.Campbell@XenSource.com>
