Now that percpu allows arbitrary embedding of the first chunk,
powerpc64 can easily be converted to dynamic percpu allocator.
Convert it. powerpc supports several large page sizes. Cap atom_size
at 1M. There isn't much to gain by going above that anyway.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Conflicts:
arch/sparc/kernel/smp_64.c
arch/x86/kernel/cpu/perf_counter.c
arch/x86/kernel/setup_percpu.c
drivers/cpufreq/cpufreq_ondemand.c
mm/percpu.c
Conflicts in core and arch percpu codes are mostly from commit
ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many
num_possible_cpus() with nr_cpu_ids. As for-next branch has moved all
the first chunk allocators into mm/percpu.c, the changes are moved
from arch code to mm/percpu.c.
Signed-off-by: Tejun Heo <tj@kernel.org>
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (27 commits)
perf_counter: Zero dead bytes from ftrace raw samples size alignment
perf_counter: Subtract the buffer size field from the event record size
perf_counter: Require CAP_SYS_ADMIN for raw tracepoint data
perf_counter: Correct PERF_SAMPLE_RAW output
perf tools: callchain: Fix bad rounding of minimum rate
perf_counter tools: Fix libbfd detection for systems with libz dependency
perf: "Longum est iter per praecepta, breve et efficax per exempla"
perf_counter: Fix a race on perf_counter_ctx
perf_counter: Fix tracepoint sampling to be part of generic sampling
perf_counter: Work around gcc warning by initializing tracepoint record unconditionally
perf tools: callchain: Fix sum of percentages to be 100% by displaying amount of ignored chains in fractal mode
perf tools: callchain: Fix 'perf report' display to be callchain by default
perf tools: callchain: Fix spurious 'perf report' warnings: ignore empty callchains
perf record: Fix the -A UI for empty or non-existent perf.data
perf util: Fix do_read() to fail on EOF instead of busy-looping
perf list: Fix the output to not include tracepoints without an id
perf_counter/powerpc: Fix oops on cpus without perf_counter hardware support
perf stat: Fix tool option consistency: rename -S/--scale to -c/--scale
perf report: Add debug help for the finding of symbol bugs - show the symtab origin (DSO, build-id, kernel, etc)
perf report: Fix per task mult-counter stat reporting
...
On an iMac G5, the b43 driver is failing to initialise because trying to
set the dma mask to 30-bit fails. Even though there's only 512MiB of RAM
in the machine anyway:
https://bugzilla.redhat.com/show_bug.cgi?id=514787
We should probably let it succeed if the available RAM in the system
doesn't exceed the requested limit.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'kvm-updates/2.6.31' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: Avoid redelivery of edge interrupt before next edge
KVM: MMU: limit rmap chain length
KVM: ia64: fix build failures due to ia64/unsigned long mismatches
KVM: Make KVM_HPAGES_PER_HPAGE unsigned long to avoid build error on powerpc
KVM: fix ack not being delivered when msi present
KVM: s390: fix wait_queue handling
KVM: VMX: Fix locking imbalance on emulation failure
KVM: VMX: Fix locking order in handle_invalid_guest_state
KVM: MMU: handle n_free_mmu_pages > n_alloc_mmu_pages in kvm_mmu_change_mmu_pages
KVM: SVM: force new asid on vcpu migration
KVM: x86: verify MTRR/PAT validity
KVM: PIT: fix kpit_elapsed division by zero
KVM: Fix KVM_GET_MSR_INDEX_LIST
If we have the powerpc perf_counter backend compiled in, but
the cpu we are running on is one where we don't support the
PMU, we currently oops in hw_perf_group_sched_in if we try to
use any counters, because ppmu is NULL in that case, and we
unconditionally dereference ppmu.
This fixes the problem by adding a check if ppmu is NULL at the
beginning of hw_perf_group_sched_in, and also at the beginning
of the other functions that get called from the perf_counter
core, i.e. hw_perf_disable, hw_perf_enable, and
hw_perf_counter_setup.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: benh@kernel.crashing.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If the current CPU doesn't support performance counters,
cur_cpu_spec->oprofile_cpu_type can be NULL. The current
perf_counter modules don't test for that case and would thus
crash at boot time.
Bug reported by David Woodhouse.
Reported-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Paul Mackerras <paulus@samba.org>
LKML-Reference: <19066.48028.446975.501454@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Eliminates this compiler warning:
arch/powerpc/kvm/../../../virt/kvm/kvm_main.c:1178: error: integer overflow in expression
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Avi Kivity <avi@redhat.com>
General update of defconfig including the following notable changes:
- Enable Highmem support.
- Support for PCMCIA based daughter card.
Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
General update of defconfig including the following notable changes:
- Enable GPIO access via sysfs on GE Fanuc's PPC9A.
- Enable Highmem support.
- Support for PCMCIA based daughter card.
Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
U-Boot maps PCI IO at 0xe0300000, while current dts files specify
0xe2000000. This leads to the following oops with CONFIG_8139TOO_PIO=y.
8139too Fast Ethernet driver 0.9.28
Machine check in kernel mode.
Caused by (from SRR1=41000): Transfer error ack signal
Oops: Machine check, sig: 7 [#1]
MPC837x RDB
[...]
NIP [00000900] 0x900
LR [c0439df8] rtl8139_init_board+0x238/0x524
Call Trace:
[cf831d90] [c0439dcc] rtl8139_init_board+0x20c/0x524 (unreliable)
[cf831de0] [c043a15c] rtl8139_init_one+0x78/0x65c
[cf831e40] [c0235250] pci_call_probe+0x20/0x30
[...]
This patch fixes the issue by specifying the correct PCI IO base
address.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Sometimes (e.g. when there are no UEMs attached to a board)
fsl_pq_mdio_find_free() fails to find a spare address for a TBI PHY,
this is because get_phy_id() returns bogus 0x0000ffff values
(0xffffffff is expected), and therefore mdio bus probing fails with
the following message:
fsl-pq_mdio: probe of e0082120.mdio failed with error -16
And obviously ethernet doesn't work after this.
This patch solves the problem by adding tbi-phy node into mdio node,
so that we won't scan for spare addresses, we'll just use a fixed one.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Linux isn't able to detect link changes on ethernet ports that were
used by U-Boot. This is because U-Boot wrongly clears interrupt
polarity bit (INTPOL, 0x400) in the extended status register (EXT_SR,
0x1b) of Marvell PHYs.
There is no easy way for PHY drivers to know IRQ line polarity (we
could extract it from the device tree and pass it to phydevs, but
that'll be quite a lot of work), so for now just reset the PHYs to
their default states.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
In switch_mmu_context() if we call steal_context_smp() to get a context
to use we shouldn't fall through and than call steal_context_up(). Doing
so can be problematic in that the 'mm' that steal_context_up() ends up
using will not get marked dirty in the stale_map[] for other CPUs that
might have used that mm. Thus we could end up with stale TLB entries in
the other CPUs that can cause all kinda of havoc.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
mm: Pass virtual address to [__]p{te,ud,md}_free_tlb()
Upcoming paches to support the new 64-bit "BookE" powerpc architecture
will need to have the virtual address corresponding to PTE page when
freeing it, due to the way the HW table walker works.
Basically, the TLB can be loaded with "large" pages that cover the whole
virtual space (well, sort-of, half of it actually) represented by a PTE
page, and which contain an "indirect" bit indicating that this TLB entry
RPN points to an array of PTEs from which the TLB can then create direct
entries. Thus, in order to invalidate those when PTE pages are deleted,
we need the virtual address to pass to tlbilx or tlbivax instructions.
The old trick of sticking it somewhere in the PTE page struct page sucks
too much, the address is almost readily available in all call sites and
almost everybody implemets these as macros, so we may as well add the
argument everywhere. I added it to the pmd and pud variants for consistency.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: David Howells <dhowells@redhat.com> [MN10300 & FRV]
Acked-by: Nick Piggin <npiggin@suse.de>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When moving load_up_altivec to vector.S a typo in a comment caused a
thinko setting the wrong variable.
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
On booke processors, gdb is seeing spurious SIGTRAPs when setting a
watchpoint.
user_disable_single_step() simply quits when the DAC is non-zero. It should
be clearing the DBCR0_IC and DBCR0_BT bits from the dbcr0 register and
TIF_SINGLESTEP from the thread flag.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (50 commits)
perf report: Add "Fractal" mode output - support callchains with relative overhead rate
perf_counter tools: callchains: Manage the cumul hits on the fly
perf report: Change default callchain parameters
perf report: Use a modifiable string for default callchain options
perf report: Warn on callchain output request from non-callchain file
x86: atomic64: Inline atomic64_read() again
x86: atomic64: Clean up atomic64_sub_and_test() and atomic64_add_negative()
x86: atomic64: Improve atomic64_xchg()
x86: atomic64: Export APIs to modules
x86: atomic64: Improve atomic64_read()
x86: atomic64: Code atomic(64)_read and atomic(64)_set in C not CPP
x86: atomic64: Fix unclean type use in atomic64_xchg()
x86: atomic64: Make atomic_read() type-safe
x86: atomic64: Reduce size of functions
x86: atomic64: Improve atomic64_add_return()
x86: atomic64: Improve cmpxchg8b()
x86: atomic64: Improve atomic64_read()
x86: atomic64: Move the 32-bit atomic64_t implementation to a .c file
x86: atomic64: The atomic64_t data type should be 8 bytes aligned on 32-bit too
perf report: Annotate variable initialization
...
Pull the initial preempt_count value into a single
definition site.
Maintainers for: alpha, ia64 and m68k, please have a look,
your arch code is funny.
The header magic is a bit odd, but similar to the KERNEL_DS
one, CPP waits with expanding these macros until the
INIT_THREAD_INFO macro itself is expanded, which is in
arch/*/kernel/init_task.c where we've already included
sched.h so we're good.
Cc: tony.luck@intel.com
Cc: rth@twiddle.net
Cc: geert@linux-m68k.org
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Discarded sections in different archs share some commonality but have
considerable differences. This led to linker script for each arch
implementing its own /DISCARD/ definition, which makes maintaining
tedious and adding new entries error-prone.
This patch makes all linker scripts to move discard definitions to the
end of the linker script and use the common DISCARDS macro. As ld
uses the first matching section definition, archs can include default
discarded sections by including them earlier in the linker script.
ia64 is notable because it first throws away some ia64 specific
subsections and then include the rest of the sections into the final
image, so those sections must be discarded before the inclusion.
defconfig compile tested for x86, x86-64, powerpc, powerpc64, ia64,
alpha, sparc, sparc64 and s390. Michal Simek tested microblaze.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Tested-by: Michal Simek <monstr@monstr.eu>
Cc: linux-arch@vger.kernel.org
Cc: Michal Simek <monstr@monstr.eu>
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Tony Luck <tony.luck@intel.com>
Current implementation of spin_event_timeout can be interrupted by an
IRQ or context switch after testing the condition, but before checking
the timeout. This can cause the loop to report a timeout when the
condition actually became true in the middle.
This patch adds one final check of the condition upon exit of the loop
if the last test of the condition was still false.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pr_debug() can now result in code being generated even when DEBUG
is not defined. That's not really desirable in some places.
With CONFIG_DYNAMIC_DEBUG=y:
size before:
text data bss dec hex filename
2036 368 8 2412 96c arch/powerpc/mm/pgtable.o
size after:
text data bss dec hex filename
1677 248 8 1933 78d arch/powerpc/mm/pgtable.o
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pr_debug() can now result in code being generated even when DEBUG
is not defined. That's not really desirable in some places.
With CONFIG_DYNAMIC_DEBUG=y:
size before:
text data bss dec hex filename
7083 1616 0 8699 21fb arch/powerpc/../axon_msi.o
size after:
text data bss dec hex filename
5772 1208 0 6980 1b44 arch/powerpc/../axon_msi.o
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pr_debug() can now result in code being generated even when DEBUG
is not defined. That's not really desirable in some places.
With CONFIG_DYNAMIC_DEBUG=y:
size before:
text data bss dec hex filename
3252 384 0 3636 e34 arch/powerpc/mm/gup.o
size after:
text data bss dec hex filename
2576 96 0 2672 a70 arch/powerpc/mm/gup.o
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pr_debug() can now result in code being generated even when DEBUG
is not defined. That's not really desirable in some places.
With CONFIG_DYNAMIC_DEBUG=y:
size before:
text data bss dec hex filename
3261 416 4 3681 e61 arch/powerpc/mm/slb.o
size after:
text data bss dec hex filename
2861 248 4 3113 c29 arch/powerpc/mm/slb.o
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pr_debug() can now result in code being generated even when DEBUG
is not defined. That's not really desirable in some places.
With CONFIG_DYNAMIC_DEBUG=y:
size before:
text data bss dec hex filename
1508 48 28 1584 630 powerpc/mm/mmu_context_nohash.o
size after:
text data bss dec hex filename
1088 0 28 1116 45c powerpc/mm/mmu_context_nohash.o
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pr_debug() can now result in code being generated even when DEBUG
is not defined. That's not really desirable in some places.
With CONFIG_DYNAMIC_DEBUG=y:
size before:
text data bss dec hex filename
7720 5488 296 13504 34c0 platforms/pseries/xics.o
size after:
text data bss dec hex filename
7535 5456 296 13287 33e7 platforms/pseries/xics.o
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pr_debug() can now result in code being generated even when DEBUG
is not defined. That's not really desirable in some places.
In particular, pSeries_lpar_hpte_insert() goes from 185 instructions
to 77 instructions as a result of this patch. Luckily that code
isn't called very often ...
With CONFIG_DYNAMIC_DEBUG=y:
size before:
text data bss dec hex filename
7284 1552 296 9132 23ac platforms/pseries/lpar.o
size after:
text data bss dec hex filename
5806 1096 296 7198 1c1e platforms/pseries/lpar.o
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With -Werror enabled during the build, the warp.c file fails to build
due to the temp_isr function not containing a return statement. This
fixes the build error and documents that the function never returns.
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
The GPIO LEDS driver now has a default state of "keep". Update the Warp DTS
and platform file to take advantage of this new state. This removes the
hardcoding of the two LEDs on the Warp.
Signed-off-by: Sean MacLennan <smaclennan@pikatech.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Pull linus#master to merge PER_CPU_DEF_ATTRIBUTES and alpha build fix
changes. As alpha in percpu tree uses 'weak' attribute instead of
inline assembly, there's no need for __used attribute.
Conflicts:
arch/alpha/include/asm/percpu.h
arch/mn10300/kernel/vmlinux.lds.S
include/linux/percpu-defs.h
POWER7 has the same PR/HV bit layout as POWER6, so set the flag.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: a.p.zijlstra@chello.nl
Cc: benh@kernel.crashing.org
LKML-Reference: <20090701030701.GI3563@kryten>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (47 commits)
perf report: Add --symbols parameter
perf report: Add --comms parameter
perf report: Add --dsos parameter
perf_counter tools: Adjust only prelinked symbol's addresses
perf_counter: Provide a way to enable counters on exec
perf_counter tools: Reduce perf stat measurement overhead/skew
perf stat: Use percentages for scaling output
perf_counter, x86: Update x86_pmu after WARN()
perf stat: Micro-optimize the code: memcpy is only required if no event is selected and !null_run
perf stat: Improve output
perf stat: Fix multi-run stats
perf stat: Add -n/--null option to run without counters
perf_counter tools: Remove dead code
perf_counter: Complete counter swap
perf report: Print sorted callchains per histogram entries
perf_counter tools: Prepare a small callchain framework
perf record: Fix unhandled io return value
perf_counter tools: Add alias for 'l1d' and 'l1i'
perf-report: Add bare minimum PERF_EVENT_READ parsing
perf-report: Add modes for inherited stats and no-samples
...
When using 64k page sizes, our PTE pages are split in two halves,
the second half containing the "extension" used to keep track of
individual 4k pages when not using HW 64k pages.
However, our page tables used for hugetlb have a slightly different
format and don't carry that "second half".
Our code that batched PTEs to be invalidated unconditionally reads
the "second half" (to put it into the batch), which means that when
called to invalidate hugetlb PTEs, it will access unrelated memory.
It breaks when CONFIG_DEBUG_PAGEALLOC is enabled.
This fixes it by only accessing the second half when the _PAGE_COMBO
bit is set in the first half, which indicates that we are dealing with
a "combo" page which represents 16x4k subpages. Anything else shouldn't
have this bit set and thus not require loading from the second half.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The function udbg_44x_as1_flush() has the wrong prototype causing
a warning when enabling 440 early debug.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
dev_set_name() takes a format string, so use it properly and avoid
a warning with recent gcc's
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
spin_lock() can hang if called while the timebase is frozen,
so use a raw lock instead, also disable interrupts while
at it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Several platforms use their own copy of what is essentially the same code,
using RTAS to synchronize the timebases when bringing up new CPUs. This
moves it all into a single common implementation and additionally
turns the spinlock into a raw spinlock since the former can rely on
the timebase not being frozen when spinlock debugging is enabled, and finally
masks interrupts while the timebase is disabled.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
RTAS currently uses a normal spinlock. However it can be called from
contexts where this is not necessarily a good idea. For example, it
can be called while syncing timebases, with the core timebase being
frozen. Unfortunately, that will deadlock in case of lock contention
when spinlock debugging is enabled as the spin lock debugging code
will try to use __delay() which ... relies on the timebase being
enabled.
Also RTAS can be used in some low level IRQ handling code path so it
may as well be a raw spinlock for -rt sake.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Based on initial work from: Dale Farnsworth <dale@farnsworth.org>
Add the low level irq tracing hooks for 32-bit powerpc needed
to enable full lockdep functionality.
The approach taken to deal with the code in entry_32.S is that
we don't trace all the transitions of MSR:EE when we just turn
it off to peek at TI_FLAGS without races. Only when we are
calling into C code or returning from exceptions with a state
that have changed from what lockdep thinks.
There's a little bugger though: If we take an exception that
keeps interrupts enabled (such as an alignment exception) while
interrupts are enabled, we will call trace_hardirqs_on() on the
way back spurriously. Not a big deal, but to get rid of it would
require remembering in pt_regs that the exception was one of the
type that kept interrupts enabled which we don't know at this
stage. (Well, we could test all cases for regs->trap but that
sucks too much).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Kumar Gala <galak@kernel.crashing.org>
The 32-bit kernel relies on some memory being mapped covering
the kernel text,data and bss at least, early during boot before
the full MMU setup is done. On 32-bit "classic" processors, this
is done using BAT registers.
On 601, the size of BATs is limited to 8M and we use 2 of them
for that initial mapping. This can become quite tight when enabling
features like lockdep, so let's use a 3rd one to bump that mapping
from 16M to 24M. We keep the 4th BAT free as it can be useful for
debugging early boot code to map things like serial ports.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Those functions are way too big to be inline, besides, kmap_atomic()
wants to call debug_kmap_atomic() which isn't exported for modules
and causes module link failures.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>