So prepare to make one more clean of early_res.c.

-v2: don't need to reserve first page in early_res
     because we already mark that in e820 as reserved already.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-20-git-send-email-yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Jens found the following crash/regression:

[    0.000000] found SMP MP-table at [ffff8800000fdd80] fdd80
[    0.000000] Kernel panic - not syncing: Overlapping early reservations 12-f011 MP-table mpc to 0-fff BIOS data page

and

[    0.000000] Kernel panic - not syncing: Overlapping early reservations 12-f011 MP-table mpc to 6000-7fff TRAMPOLINE

and bisected it to b24c2a92 ("x86: Move find_smp_config()
earlier and avoid bootmem usage").

It turns out the BIOS is using the first 64k for mptable,
without reserving it.

So try to find good range for the real-mode trampoline instead of
hard coding it, in case some bios tries to use that range for sth.
Reported-by: NJens Axboe <jens.axboe@oracle.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Tested-by: NJens Axboe <jens.axboe@oracle.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
LKML-Reference: <4B21630A.6000308@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Moorestown MID devices need to be detected early in the boot process
to setup and do not call x86_default_early_setup as there is no EBDA
region to reserve.

[ Copied the minimal code from Jacobs latest MRST series ]
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Jacob Pan <jacob.jun.pan@intel.com>

Platforms like Moorestown require early setup and want to avoid the
call to reserve_ebda_region. The x86_init override is too late when
the MRST detection happens in setup_arch. Move the default i386
x86_init overrides and the call to reserve_ebda_region into a separate
function which is called as the default of a switch case depending on
the hardware_subarch id in boot params. This allows us to add a case
for MRST and let MRST have its own early setup function.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

32bit and also the numaq code have special requirements on the
ioapic_id setup. Convert it to a x86_init_ops function and get rid
of the quirks and #ifdefs
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

reserve_ebda_region needs to be called befor start_kernel. Moorestown
needs to override it. Make it a x86_init_ops function and initialize
it with the default reserve_ebda_region.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The 32bit and the 64bit code are slighty different in the reservation
of standard resources. Also the upcoming Moorestown support needs its
own version of that.

Add it to x86_init_ops and initialize it with the 64bit default. 32bit
overrides it in early boot. Now moorestown can add it's own override
w/o sprinkling the code with more #ifdefs
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

probe_roms is only used on 32bit. Add it to the x86_init ops and
remove the #ifdefs.

Default initializer is x86_init_noop() which is overridden in
the 32bit boot code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Impact: use new interface instead of previous ad hoc implementation

Rather than having special purpose init_pg_table_start/end variables
to delimit the kernel pagetable built by head_32.S, just use the brk
mechanism to extend the bss for the new pagetable.

This patch removes init_pg_table_start/end and pg0, defines __brk_base
(which is page-aligned and immediately follows _end), initializes
the brk region to start there, and uses it for the 32-bit pagetable.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: new interface

Add a brk()-like allocator which effectively extends the bss in order
to allow very early code to do dynamic allocations.  This is better than
using statically allocated arrays for data in subsystems which may never
get used.

The space for brk allocations is in the bss ELF segment, so that the
space is mapped properly by the code which maps the kernel, and so
that bootloaders keep the space free rather than putting a ramdisk or
something into it.

The bss itself, delimited by __bss_stop, ends before the brk area
(__brk_base to __brk_limit).  The kernel text, data and bss is reserved
up to __bss_stop.

Any brk-allocated data is reserved separately just before the kernel
pagetable is built, as that code allocates from unreserved spaces
in the e820 map, potentially allocating from any unused brk memory.
Ultimately any unused memory in the brk area is used in the general
kernel memory pool.

Initially the brk space is set to 1MB, which is probably much larger
than any user needs (the largest current user is i386 head_32.S's code
to build the pagetables to map the kernel, which can get fairly large
with a big kernel image and no PSE support).  So long as the system
has sufficient memory for the bootloader to reserve the kernel+1MB brk,
there are no bad effects resulting from an over-large brk.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: fix trampoline sizing bug, save space

While debugging a suspend-to-RAM related issue it occured to me that
if the trampoline code had grown past 4 KB, we would have been
allocating too little memory for it, since the 4 KB size of the
trampoline is hardcoded into arch/x86/kernel/e820.c .  Change that
by making the kernel compute the trampoline size and allocate as much
memory as necessary.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch extracts the common part of head32.c and head64.c into head.c.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Cc: andi@firstfloor.org
Cc: mingo@redhat.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

introduce init_pg_table_start, so xen PV could specify the value.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

move early_res related from e820_64.c to e820.c
make edba detection to be done in head32.c
remove smp_alloc_memory, because we have fixed trampoline address now.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>

 arch/x86/kernel/e820.c              |  214 ++++++++++++++++++++++++++++++++++++
 arch/x86/kernel/e820_64.c           |  196 --------------------------------
 arch/x86/kernel/head32.c            |   76 ++++++++++++
 arch/x86/kernel/setup_32.c          |  109 +++---------------
 arch/x86/kernel/smpboot.c           |   17 --
 arch/x86/kernel/trampoline.c        |    2
 arch/x86/mach-voyager/voyager_smp.c |    9 -
 include/asm-x86/e820.h              |    6 +
 include/asm-x86/e820_64.h           |    9 -
 include/asm-x86/smp.h               |    1
 arch/x86/kernel/e820.c              |  214 ++++++++++++++++++++++++++++++++++++
 arch/x86/kernel/e820_64.c           |  196 --------------------------------
 arch/x86/kernel/head32.c            |   76 ++++++++++++
 arch/x86/kernel/setup_32.c          |  109 +++---------------
 arch/x86/kernel/smpboot.c           |   17 --
 arch/x86/kernel/trampoline.c        |    2
 arch/x86/mach-voyager/voyager_smp.c |    9 -
 include/asm-x86/e820.h              |    6 +
 include/asm-x86/e820_64.h           |    9 -
 include/asm-x86/smp.h               |    1
 arch/x86/kernel/e820.c              |  214 ++++++++++++++++++++++++++++++++++++
 arch/x86/kernel/e820_64.c           |  196 --------------------------------
 arch/x86/kernel/head32.c            |   76 ++++++++++++
 arch/x86/kernel/setup_32.c          |  109 +++---------------
 arch/x86/kernel/smpboot.c           |   17 --
 arch/x86/kernel/trampoline.c        |    2
 arch/x86/mach-voyager/voyager_smp.c |    9 -
 include/asm-x86/e820.h              |    6 +
 include/asm-x86/e820_64.h           |    9 -
 include/asm-x86/smp.h               |    1
 10 files changed, 320 insertions(+), 319 deletions(-)
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Copy x86_64 and add a head32.c so we can start moving early
architecture initialization out of assembly.

[ Sam Ravnborg <sam@ravnborg.org>: updated it to x86 ]
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>