Put config options for Xen after the core pieces are in place.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

Xen maintains a base clock which measures nanoseconds since system
boot.  This is provided to guests via a shared page which contains a
base time in ns, a tsc timestamp at that point and tsc frequency
parameters.  Guests can compute the current time by reading the tsc
and using it to extrapolate the current time from the basetime.  The
hypervisor makes sure that the frequency parameters are updated
regularly, paricularly if the tsc changes rate or stops.

This is implemented as a clocksource, so the interface to the rest of
the kernel is a simple clocksource which simply returns the current
time directly in nanoseconds.

Xen also provides a simple timer mechanism, which allows a timeout to
be set in the future.  When that time arrives, a timer event is sent
to the guest.  There are two timer interfaces:
 - An old one which also delivers a stream of (unused) ticks at 100Hz,
   and on the same event, the actual timer events.  The 100Hz ticks
   cause a lot of spurious wakeups, but are basically harmless.
 - The new timer interface doesn't have the 100Hz ticks, and can also
   fail if the specified time is in the past.

This code presents the Xen timer as a clockevent driver, and uses the
new interface by preference.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>

Xen implements interrupts in terms of event channels.  Each guest
domain gets 1024 event channels which can be used for a variety of
purposes, such as Xen timer events, inter-domain events,
inter-processor events (IPI) or for real hardware IRQs.

Within the kernel, we map the event channels to IRQs, and implement
the whole interrupt handling using a Xen irq_chip.

Rather than setting NR_IRQ to 1024 under PARAVIRT in order to
accomodate Xen, we create a dynamic mapping between event channels and
IRQs.  Ideally, Linux will eventually move towards dynamically
allocating per-irq structures, and we can use a 1:1 mapping between
event channels and irqs.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Eric W. Biederman <ebiederm@xmission.com>

Xen pagetable handling, including the machinery to implement direct
pagetables.

Xen presents the real CPU's pagetables directly to guests, with no
added shadowing or other layer of abstraction.  Naturally this means
the hypervisor must maintain close control over what the guest can put
into the pagetable.

When the guest modifies the pte/pmd/pgd, it must convert its
domain-specific notion of a "physical" pfn into a global machine frame
number (mfn) before inserting the entry into the pagetable.  Xen will
check to make sure the domain is allowed to create a mapping of the
given mfn.

Xen also requires that all mappings the guest has of its own active
pagetable are read-only.  This is relatively easy to implement in
Linux because all pagetables share the same pte pages for kernel
mappings, so updating the pte in one pagetable will implicitly update
the mapping in all pagetables.

Normally a pagetable becomes active when you point to it with cr3 (or
the Xen equivalent), but when you do so, Xen must check the whole
pagetable for correctness, which is clearly a performance problem.

Xen solves this with pinning which keeps a pagetable effectively
active even if its currently unused, which means that all the normal
update rules are enforced.  This means that it need not revalidate the
pagetable when loading cr3.

This patch has a first-cut implementation of pinning, but it is more
fully implemented in a later patch.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

This patch is a rollup of all the core pieces of the Xen
implementation, including:
 - booting and setup
 - pagetable setup
 - privileged instructions
 - segmentation
 - interrupt flags
 - upcalls
 - multicall batching

BOOTING AND SETUP

The vmlinux image is decorated with ELF notes which tell the Xen
domain builder what the kernel's requirements are; the domain builder
then constructs the address space accordingly and starts the kernel.

Xen has its own entrypoint for the kernel (contained in an ELF note).
The ELF notes are set up by xen-head.S, which is included into head.S.
In principle it could be linked separately, but it seems to provoke
lots of binutils bugs.

Because the domain builder starts the kernel in a fairly sane state
(32-bit protected mode, paging enabled, flat segments set up), there's
not a lot of setup needed before starting the kernel proper.  The main
steps are:
  1. Install the Xen paravirt_ops, which is simply a matter of a
     structure assignment.
 ...

Add Xen interface header files. These are taken fairly directly from
the Xen tree, but somewhat rearranged to suit the kernel's conventions.

Define macros and inline functions for doing hypercalls into the
hypervisor.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ian Pratt <ian.pratt@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

Add the "nosegneg" fake capabilty to the vsyscall page notes. This is
used by the runtime linker to select a glibc version which then
disables negative-offset accesses to the thread-local segment via
%gs. These accesses require emulation in Xen (because segments are
truncated to protect the hypervisor address space) and avoiding them
provides a measurable performance boost.

Signed-off-by: Ian Pratt <ian.pratt@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Acked-by: Zachary Amsden <zach@vmware.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Ulrich Drepper <drepper@redhat.com>

The tsc-based get_scheduled_cycles interface is not a good match for
Xen's runstate accounting, which reports everything in nanoseconds.

This patch replaces this interface with a sched_clock interface, which
matches both Xen and VMI's requirements.

In order to do this, we:
   1. replace get_scheduled_cycles with sched_clock
   2. hoist cycles_2_ns into a common header
   3. update vmi accordingly

One thing to note: because sched_clock is implemented as a weak
function in kernel/sched.c, we must define a real function in order to
override this weak binding.  This means the usual paravirt_ops
technique of using an inline function won't work in this case.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Dan Hecht <dhecht@vmware.com>
Cc: john stultz <johnstul@us.ibm.com>

In a virtual environment, device drivers such as legacy IDE will waste
quite a lot of time probing for their devices which will never appear.
This helper function allows a paravirt implementation to lay claim to
the whole iomem and ioport space, thereby disabling all device drivers
trying to claim IO resources.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>

Allocate/release a chunk of vmalloc address space:
 alloc_vm_area reserves a chunk of address space, and makes sure all
 the pagetables are constructed for that address range - but no pages.

 free_vm_area releases the address space range.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ian Pratt <ian.pratt@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: "Jan Beulich" <JBeulich@novell.com>
Cc: "Andi Kleen" <ak@muc.de>

__supported_pte_mask is needed when constructing pte values.  Xen
device drivers need to do this to make mappings of foreign pages (ie,
pages granted to us by other domains).

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>

Paravirt implementations need to set the sibling map on new cpus.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>

Paravirt implementations need to store cpu info when bringing up cpus.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>

Make globally leave_mm visible, specifically so that Xen can use it to
shoot-down lazy uses of cr3.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

When running with CONFIG_PARAVIRT, we may want lots of IRQs even if
there's no IO APIC.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>

Add a hook so that the paravirt backend knows when the allocator is
ready.  This is useful for the obvious reason that the allocator is
available, but the other side-effect of having the bootmem allocator
available is that each page now has an associated "struct page".

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>

It's useful to know which mm is allocating a pagetable.  Xen uses this
to determine whether the pagetable being added to is pinned or not.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>

Use existing elfnote.h to generate vsyscall notes, rather than doing
it locally.  Changes elfnote.h a bit to suit, since this is the first
asm user, and it wasn't quite right.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.com>

Rather than using a tri-state integer for the wait flag in
call_usermodehelper_exec, define a proper enum, and use that.  I've
preserved the integer values so that any callers I've missed should
still work OK.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: David Howells <dhowells@redhat.com>

Various pieces of code around the kernel want to be able to trigger an
orderly poweroff.  This pulls them together into a single
implementation.

By default the poweroff command is /sbin/poweroff, but it can be set
via sysctl: kernel/poweroff_cmd.  This is split at whitespace, so it
can include command-line arguments.

This patch replaces four other instances of invoking either "poweroff"
or "shutdown -h now": two sbus drivers, and acpi thermal
management.

sparc64 has its own "powerd"; still need to determine whether it should
be replaced by orderly_poweroff().

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Acked-by: Len Brown <lenb@kernel.org>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David S. Miller <davem@davemloft.net>

Rather than having hundreds of variations of call_usermodehelper for
various pieces of usermode state which could be set up, split the
info allocation and initialization from the actual process execution.

This means the general pattern becomes:
 info = call_usermodehelper_setup(path, argv, envp); /* basic state */
 call_usermodehelper_<SET EXTRA STATE>(info, stuff...);	/* extra state */
 call_usermodehelper_exec(info, wait);	/* run process and free info */

This patch introduces wrappers for all the existing calling styles for
call_usermodehelper_*, but folds their implementations into one.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Bj?rn Steinbrink <B.Steinbrink@gmx.de>
Cc: Randy Dunlap <randy.dunlap@oracle.com>

argv_split() is a helper function which takes a string, splits it at
whitespace, and returns a NULL-terminated argv vector.  This is
deliberately simple - it does no quote processing of any kind.

[ Seems to me that this is something which is already being done in
  the kernel, but I couldn't find any other implementations, either to
  steal or replace.  Keep an eye out. ]

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>

Add a kstrndup function, modelled on strndup.  Like strndup this
returns a string copied into its own allocated memory, but it copies
no more than the specified number of bytes from the source.

Remove private strndup() from irda code.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@mandriva.com>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Panagiotis Issaris <takis@issaris.org>
Cc: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>

This is a reimplementation of the zs driver for the serial subsystem.  Any
resemblance to the old driver is purely coincidential.  ;-) I do hope I got
the handling of modem lines right -- better do not tackle me about the
issue unless you feel too good...

Any users of the old driver: please note the numbers of the serial lines
have now been swapped, i.e.  ttyS0 <-> ttyS1 and ttyS2 <-> ttyS3.  It has
to do with the modem lines mentioned above; basically the port A in a given
chip has to be initialised before the port B if you want to use the latter
as the serial console (which is usually the case), as operations on modem
lines of the serial line associated with the port B access both ports (see
the comment at the top of the driver for the details of wiring used).
Please update your scripts.

This is also the reason each SCC now requests an IRQ once only (as seen in
"/proc/interrupts") -- the handler takes care of both ports at once as the
line associated with the port B ha...

early_serial_setup was removed from serial.h, but forgot to put in
serial_8250.h

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We can't show the extra logo from boot code if FB is built as a module.
Make the FB_LOGO_EXTRA depend on FB=y.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If, in dm_create_persistent(), the call to create_singlethread_workqueue()
fails then we'll return without freeing the memory allocated to 'ps', thus
leaking sizeof(struct pstore) bytes.  This patch fixes the leak.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With the slab zeroing allocations cleanups Christoph stubbed in a generic
kzalloc(), which was missed on SLOB. Follow the SLAB/SLUB changes and
kill off the __kzalloc() wrapper that SLOB was using.

Reported-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The old IDE driver is not ready to take generic SCSI commands, even if
it uses them for some specific issues (ie the tray open/close ioctls for
IDE CD-ROM's). Pointed out by Bartlomiej.

I'm sure we'll have it fixed properly soon enough, but for now we should
not allow it to cause problems.

Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

I really don't see anybody else wanting to select it ;)

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
  [S390] Fix broken logic, SIGA flags must be bitwise ORed
  [S390] cio: Dont print trailing \0 in modalias_show().
  [S390] Simplify stack trace.
  [S390] z/VM unit record device driver
  [S390] vmcp cleanup
  [S390] qdio: output queue stall on FCP and network devices
  [S390] Fix disassembly of RX_URRD, SI_URD & PC-relative instructions.
  [S390] Update default configuration.

* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog: (21 commits)
  [WATCHDOG] at32ap700x_wdt.c - Fix compilation warnings
  [WATCHDOG] at32ap700x_wdt.c - Add spinlock support
  [WATCHDOG] at32ap700x_wdt.c - Add nowayout + MAGICCLOSE features
  [WATCHDOG] at32ap700x_wdt.c - timeout module parameter patch
  [WATCHDOG] at32ap700x_wdt.c - checkpatch.pl-0.05 clean-up's
  [WATCHDOG] change s3c2410_wdt to using dev_() macros for output
  [WATCHDOG] s3c2410_wdt announce initialisation
  [WATCHDOG] at32ap700x-wdt: add iounmap if probe function fails
  [WATCHDOG] at32ap700x-wdt: add missing iounmap in _remove
  [WATCHDOG] watchdog-driver-for-at32ap700x-devices-fix-2
  [WATCHDOG] watchdog-driver-for-at32ap700x-devices-fix
  [WATCHDOG] Watchdog driver for AT32AP700X devices
  [WATCHDOG] Mixcom Watchdog - CodingStyle clean-up
  [WATCHDOG] Mixcom Watchdog - clean-up printk's
  [WATCHDOG] Mixcom Watchdog - clean-up printk's
  [WATCHDOG] Mixcom Watchdog - checkcard part 2
  [WATCHDOG] Mixcom Watchdog - checkcard
  [WATCHDOG] Mixcom Watchdog - get rid of port offset's
  [WATCHDOG] Mixcom Watchdog - update "Documentation"
  [WATCHDOG] Remove the redundant check for pwrite() in EP93XXX watchdog.
  ...

* 'bsg' of git://git.kernel.dk/data/git/linux-2.6-block:
  bsg: fix missing space in version print
  Don't define empty struct bsg_class_device if !CONFIG_BLK_DEV_BSG
  bsg: Kconfig updates
  bsg: minor cleanup
  bsg: device hash table cleanup
  bsg: fix initialization error handling bugs
  bsg: mark FUJITA Tomonori as bsg maintainer
  bsg: convert to dynamic major
  bsg: address various review comments

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  9p: fix debug compilation error

* 'isdn-cleanup' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6:
  [ISDN] HiSax hfc_pci: minor cleanups
  [ISDN] HiSax bkm_a4t: split setup into two smaller functions
  [ISDN] HiSax enternow: split setup into 3 smaller functions
  [ISDN] HiSax netjet_u: split setup into 3 smaller functions
  [ISDN] HiSax netjet_s: code movement, prep for hotplug
  [ISDN] HiSax: move card state alloc/setup code into separate functions
  [ISDN] HiSax: move card setup into separate function

* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6:
  [SPARC64]: Kill bogus set_fs(KERNEL_DS) in do_rt_sigreturn().
  [SPARC64]: Update defconfig.
  [SPARC64]: Kill explicit %gl register reference.

* 'uninit-var' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6:
  arch/i386/* fs/* ipc/*: mark variables with uninitialized_var()
  drivers/*: mark variables with uninitialized_var()

* 'warnings' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6:
  drivers/atm/ambassador: kill uninit'd var warning, and fix bug
  [libata] sata_mv: use pci_try_set_mwi()
  drivers/infiniband/hw/mthca/mthca_qp: kill uninit'd var warning
  drivers/net/wan/sbni: kill uninit'd var warning
  drivers/mtd/ubi/eba: minor cleanup: tighten scope of a local var
  drivers/telephony/ixj: cleanup and fix gcc warning
  drivers/net/wan/pc300_drv: fix bug caught by gcc warning
  drivers/usb/misc/auerswald: fix status check, remove redundant check
  [netdrvr] eepro100, ne2k-pci: abort resume if pci_enable_device() fails
  [netdrvr] natsemi: Fix device removal bug
  kernel/auditfilter: kill bogus uninit'd-var compiler warning

... or we end up with header include order problems from hell.

E.g. on m68k this is 100% fatal - local_irq_enable() there
wants preempt_count(), which wants task_struct fields, which
we won't have when we are in smp.h pulled from sched.h.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

From: Oleg Nesterov <oleg@tv-sign.ru>

Signed-off-by: David S. Miller <davem@davemloft.net>