Drop extern for all prototypes and adjust alignment of parameters
as required after the removal.
In a few rare cases adjust linelength to conform to maximum 80 chars,
and likewise in a few rare cases adjust alignment of parameters
to static functions.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following sparse warning:
math_{32,64}.c: warning: symbol 'do_mathemu' was not declared. Should it be static?

Add prototype in processor_{32,64} and drop extern in traps_{32,64}.c
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The following asm statements generated a sparse warning:

        asm("addcc \n\t" : "=r" (((USItype)(r2)))

warning: asm output is not an lvalue

When asking on the sparse mailing list Linus replyed:

"
Those casts to (USItype) are all pointless to begin with (since the
values are of that type already!) and they mean that the expression
isn't something you can assign to (lvalue).
"

In the math emulation code drop all casts in the output
parts of the asm statements.

This fixes a lot of "warning: asm output is not an lvalue" sparse
warnings in math_32.c.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warnings:
time_32.c:63:1: warning: symbol 'rtc_lock' was not declared. Should it be static?
time_32.c:357:13: warning: symbol 'time_init' was not declared. Should it be static?
time_32.c:148:16: warning: dereference of noderef expression

Add extern definition of rtc_lock in mc146818rtc.h.
time_init() is called from init/main.c - add prototype to kernel.h.
Use proper u32 __iomem * for master_l10_counter.
Fix all users.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warning:
auxio_32.c:133:33: warning: cast removes address space of expression

To fix this auxio_power_register had to be defined as u8 _iomem.
Use proper sbus operations on the pointer.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warning:
io-unit.c:56:13: warning: incorrect type in assignment (different address spaces)

The page table for the io unit resides in __iomem.
Fix up all users of the io unit page table.
Introduce sbus helers for all read/write operations.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warning:
iommu.c:69:21: warning: incorrect type in assignment (different address spaces)

iommu_struct.regs is __iomem - fix up all users.
Introduce sbus operations for all read/write operations.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After introducing asm-generic/io.h a few things could still be cleaned up
o Drop useless macro indirection for sbus_* io access methods
  They were in the past used to hide casts between long and pointers
  but this is no longer so
o Fix function definitions for sbus memory functions so
  return value appear on same line as function name
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use asm-generic/io.h definitions where applicable.
The inxx() and outxx() methods whcih was duplicated in pcic.c +
leon_pci.c are replaced by a set of static inlins from asm-generic/io.h

iomap.c is replaced by the generic versions, but are still
present to support sparc64.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preparation for introducing asm-generic/io.h this move was required.
In asm-generic page_to_phys is placed in page.h - so do the same here.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warnings:
unaligned_32.c:146:15: warning: symbol 'safe_compute_effective_address' was not declared. Should it be static?
unaligned_32.c:235:17: warning: symbol 'kernel_unaligned_trap' was not declared. Should it be static?
unaligned_32.c:319:17: warning: symbol 'user_unaligned_trap' was not declared. Should it be static?

Add proper declarations in kernel.h + setup.h
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warnings:
auxio_32.c:23:14: warning: symbol 'auxio_register' was not declared. Should it be static?
auxio_32.c:26:13: warning: symbol 'auxio_probe' was not declared. Should it be static?
auxio_32.c:108:13: warning: symbol 'auxio_power_probe' was not declared. Should it be static?

Add proper decalarations for the above.

The leaves one sparse warning:
auxio_32.c:130:33: warning: cast removes address space of expression

This is here:
    auxio_power_register = (unsigned char *) of_ioremap()

This is __iomem that is removed from return value of of_ioremap()
The pointer is later used without any helpers in process_32.c:
    *auxio_power_register |= AUXIO_POWER_OFF;

It would be simple to introduce a few sbus() helpers.
But as I was not sure this was correct the warning are left as-is.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warning:
devices.c:114:13: warning: symbol 'device_scan' was not declared. Should it be static?

Add prototype to asm/setup.h
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following sparc32 warning:
cpu.c:430:29: warning: symbol 'cpuinfo_op' was not declared. Should it be static?

Fix following sparc64 warnings:
cpu.c:364:14: warning: symbol 'dcache_parity_tl1_occurred' was not declared. Should it be static?
cpu.c:365:14: warning: symbol 'icache_parity_tl1_occurred' was not declared. Should it be static?

Rearrange asm/cpu.h to share more stuff between sparc32 and sparc64.
Added missing include to cpu.c of kernel.h
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warnings:
setup_32.c:106:15: warning: symbol 'cmdline_memory_size' was not declared. Should it be static?
setup_32.c:270:16: warning: symbol 'fake_swapper_regs' was not declared. Should it be static?
setup_32.c:368:55: warning: Using plain integer as NULL pointer

Add missing declaration of cmdline_memory_size and remove the local one in init_32.c
fake_swapper_regs was only used locally - so defined static.
When replacing 0 with NULL also add a few spaces around operators
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warnings:
ioport.c:189:38: warning: Using plain integer as NULL pointer
ioport.c:78:25: warning: symbol 'sparc_iomap' was not declared. Should it be static?
ioport.c:403:20: warning: symbol 'sbus_dma_ops' was not declared. Should it be static?
ioport.c:684:39: warning: Using plain integer as NULL pointer

Add one missing prototype, and use NULL.
sbus_dma_ops declared static.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warnings:
irq_32.c:239:5: warning: symbol 'sparc_floppy_request_irq' was not declared. Should it be static?
irq_32.c:294:24: warning: symbol 'fdc_status' was not declared. Should it be static?
irq_32.c:297:6: warning: symbol 'pdma_vaddr' was not declared. Should it be static?
irq_32.c:300:15: warning: symbol 'pdma_size' was not declared. Should it be static?
irq_32.c:303:14: warning: symbol 'doing_pdma' was not declared. Should it be static?
irq_32.c:306:6: warning: symbol 'pdma_base' was not declared. Should it be static?
irq_32.c:309:15: warning: symbol 'pdma_areasize' was not declared. Should it be static?
irq_32.c:317:6: warning: symbol 'sparc_floppy_irq' was not declared. Should it be static?

The floppy parts were all added to iasm/setup.h - no other header files looked obvious.
floppy_32.h was not an option as this file can only be included once from the
floppy driver.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warnings:
sun4d_irq.c:146:6: warning: symbol 'sun4d_handler_irq' was not declared. Should it be static?
sun4d_irq.c:239:17: warning: symbol 'sun4d_irq' was not declared. Should it be static?
sun4d_irq.c:288:14: warning: symbol '_sun4d_build_device_irq' was not declared. Should it be static?
sun4d_irq.c:323:14: warning: symbol 'sun4d_build_device_irq' was not declared. Should it be static?
sun4d_irq.c:386:14: warning: symbol 'sun4d_build_timer_irq' was not declared. Should it be static?
sun4d_irq.c:482:13: warning: symbol 'sun4d_init_sbi_irq' was not declared. Should it be static?

Apply static when applicable, otherwise add prototype
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warnings:

sun4m_irq.c:308:6: warning: symbol 'sun4m_nmi' was not declared. Should it be static?
sun4m_irq.c:396:28: warning: incorrect type in assignment (different address spaces)
sun4m_irq.c:396:28:    expected unsigned int volatile *extern [addressable] [toplevel] master_l10_counter
sun4d_irq.c:469:28: warning: incorrect type in assignment (different address spaces)
sun4d_irq.c:469:28:    expected unsigned int volatile *extern [addressable] [toplevel] master_l10_counter

master_l10_counter is a pointer to __iomem - add annotations.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warning:
traps_32.c:47:6: error: symbol 'die_if_kernel' redeclared with different type - different modifiers

Add __noreturn to both definition and declaration
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix following warning:
init_32.c:112:22: warning: symbol 'bootmem_init' was not declared. Should it be static?

Fix by adding a proper prototype in pgtable_32.h and drop
the local prototype in srmmu.c
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove sparc64_multi_core because it's not used any more.

It was added by a2f9f6bb ("Fix {mc,smt}_capable()"), and the last uses
were removed by e637d96bf462 ("sched: Remove unused mc_capable() and
smt_capable()").
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20140304210744.16893.75929.stgit@bhelgaas-glaptop.roam.corp.google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Remove mc_capable() and smt_capable().  Neither is used.

Both were added by 5c45bf27 ("sched: mc/smt power savings sched
policy").  Uses of both were removed by 8e7fbcbc ("sched: Remove stale
power aware scheduling remnants and dysfunctional knobs").
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Link: http://lkml.kernel.org/r/20140304210737.16893.54289.stgit@bhelgaas-glaptop.roam.corp.google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This patch allows each architecture to add its specific assembly optimized
arch_mcs_spin_lock_contended and arch_mcs_spinlock_uncontended for
MCS lock and unlock functions.
Signed-off-by: NTim Chen <tim.c.chen@linux.intel.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: AswinChandramouleeswaran <aswin@hp.com>
Cc: George Spelvin <linux@horizon.com>
Cc: Rik vanRiel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: MichelLespinasse <walken@google.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Alex Shi <alex.shi@linaro.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Figo.zhang" <figo1802@gmail.com>
Cc: "Paul E.McKenney" <paulmck@linux.vnet.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Waiman Long <waiman.long@hp.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew R Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1390347382.3138.67.camel@schen9-DESKSigned-off-by: NIngo Molnar <mingo@kernel.org>

We perform a clean up of the Kbuid files in each architecture.
We order the files in each Kbuild in alphabetical order
by running the below script.

for i in arch/*/include/asm/Kbuild
do
        cat $i | gawk '/^generic-y/ {
                i = 3;
                do {
                        for (; i <= NF; i++) {
                                if ($i == "\\") {
                                        getline;
                                        i = 1;
                                        continue;
                                }
                                if ($i != "")
                                        hdr[$i] = $i;
                        }
                        break;
                } while (1);
                next;
        }
        // {
                print $0;
        }
        END {
                n = asort(hdr);
                for (i = 1; i <= n; i++)
                        print "generic-y += " hdr[i];
        }' > ${i}.sorted;
        mv ${i}.sorted $i;
done
Signed-off-by: NTim Chen <tim.c.chen@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew R Wilcox <matthew.r.wilcox@intel.com>
Cc: AswinChandramouleeswaran <aswin@hp.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: "Paul E.McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: "Figo.zhang" <figo1802@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Waiman Long <waiman.long@hp.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Alex Shi <alex.shi@linaro.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: George Spelvin <linux@horizon.com>
Cc: MichelLespinasse <walken@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
[ Fixed build bug. ]
Signed-off-by: NIngo Molnar <mingo@kernel.org>

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

For user space packet capturing libraries such as libpcap, there's
currently only one way to check which BPF extensions are supported
by the kernel, that is, commit aa1113d9 ("net: filter: return
-EINVAL if BPF_S_ANC* operation is not supported"). For querying all
extensions at once this might be rather inconvenient.

Therefore, this patch introduces a new option which can be used as
an argument for getsockopt(), and allows one to obtain information
about which BPF extensions are supported by the current kernel.

As David Miller suggests, we do not need to define any bits right
now and status quo can just return 0 in order to state that this
versions supports SKF_AD_PROTOCOL up to SKF_AD_PAY_OFFSET. Later
additions to BPF extensions need to add their bits to the
bpf_tell_extensions() function, as documented in the comment.
Signed-off-by: NMichal Sekletar <msekleta@redhat.com>
Cc: David Miller <davem@davemloft.net>
Reviewed-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A number of situations currently require the heavyweight smp_mb(),
even though there is no need to order prior stores against later
loads.  Many architectures have much cheaper ways to handle these
situations, but the Linux kernel currently has no portable way
to make use of them.

This commit therefore supplies smp_load_acquire() and
smp_store_release() to remedy this situation.  The new
smp_load_acquire() primitive orders the specified load against
any subsequent reads or writes, while the new smp_store_release()
primitive orders the specifed store against any prior reads or
writes.  These primitives allow array-based circular FIFOs to be
implemented without an smp_mb(), and also allow a theoretical
hole in rcu_assign_pointer() to be closed at no additional
expense on most architectures.

In addition, the RCU experience transitioning from explicit
smp_read_barrier_depends() and smp_wmb() to rcu_dereference()
and rcu_assign_pointer(), respectively resulted in substantial
improvements in readability.  It therefore seems likely that
replacing other explicit barriers with smp_load_acquire() and
smp_store_release() will provide similar benefits.  It appears
that roughly half of the explicit barriers in core kernel code
might be so replaced.

[Changelog by PaulMck]
Reviewed-by: N"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Victor Kaplansky <VICTORK@il.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20131213150640.908486364@infradead.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

We're going to be adding a few new barrier primitives, and in order to
avoid endless duplication make more agressive use of
asm-generic/barrier.h.

Change the asm-generic/barrier.h such that it allows partial barrier
definitions and fills out the rest with defaults.

There are a few architectures (m32r, m68k) that could probably
do away with their barrier.h file entirely but are kept for now due to
their unconventional nop() implementation.
Suggested-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: N"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Reviewed-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Victor Kaplansky <VICTORK@il.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20131213150640.846368594@infradead.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

This reverts commit 145e1c00.

This commit broke the behavior of __copy_from_user_inatomic when
it is only partially successful. Instead of returning the number
of bytes not copied, it now returns 1. This translates to the
wrong value being returned by iov_iter_copy_from_user_atomic.

xfstests generic/246 and LTP writev01 both fail on btrfs and nfs
because of this.
Signed-off-by: NDave Kleikamp <dave.kleikamp@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a few subtle races, between change_protection_range (used by
mprotect and change_prot_numa) on one side, and NUMA page migration and
compaction on the other side.

The basic race is that there is a time window between when the PTE gets
made non-present (PROT_NONE or NUMA), and the TLB is flushed.

During that time, a CPU may continue writing to the page.

This is fine most of the time, however compaction or the NUMA migration
code may come in, and migrate the page away.

When that happens, the CPU may continue writing, through the cached
translation, to what is no longer the current memory location of the
process.

This only affects x86, which has a somewhat optimistic pte_accessible.
All other architectures appear to be safe, and will either always flush,
or flush whenever there is a valid mapping, even with no permissions
(SPARC).

The basic race looks like this:

CPU A			CPU B			CPU C

						load TLB entry
make entry PTE/PMD_NUMA
			fault on entry
						read/write old page
			start migrating page
			change PTE/PMD to new page
						read/write old page [*]
flush TLB
						reload TLB from new entry
						read/write new page
						lose data

[*] the old page may belong to a new user at this point!

The obvious fix is to flush remote TLB entries, by making sure that
pte_accessible aware of the fact that PROT_NONE and PROT_NUMA memory may
still be accessible if there is a TLB flush pending for the mm.

This should fix both NUMA migration and compaction.

[mgorman@suse.de: fix build]
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NMel Gorman <mgorman@suse.de>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit ea1e7ed3 triggers build regression on sparc64.

include/linux/mm.h:1391:2: error: implicit declaration of function 'pgtable_cache_init' [-Werror=implicit-function-declaration]
arch/sparc/include/asm/pgtable_64.h:978:13: error: conflicting types for 'pgtable_cache_init' [-Werror]

It happens due headers include loop:

<linux/mm.h> -> <asm/pgtable.h> -> <asm/pgtable_64.h> ->
	<asm/tlbflush.h> -> <asm/tlbflush_64.h> -> <linux/mm.h>

Let's drop <linux/mm.h> include from asm/tlbflush_64.h.
Build tested with allmodconfig.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Mark the places when the system are in user or are in kernel.
This is used to make full dynticks system (tickless) --
CONFIG_NO_HZ_FULL dependence.
Signed-off-by: NKirill Tkhai <tkhai@yandex.ru>
CC: David Miller <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we have 64-bits for PMDs we can stop using special encodings
for the huge PMD values, and just put real PTEs in there.

We allocate a _PAGE_PMD_HUGE bit to distinguish between plain PMDs and
huge ones.  It is the same for both 4U and 4V PTE layouts.

We also use _PAGE_SPECIAL to indicate the splitting state, since a
huge PMD cannot also be special.

All of the PMD --> PTE translation code disappears, and most of the
huge PMD bit modifications and tests just degenerate into the PTE
operations.  In particular USER_PGTABLE_CHECK_PMD_HUGE becomes
trivial.

As a side effect, normal PMDs don't shift the physical address around.
This also speeds up the page table walks in the TLB miss paths since
they don't have to do the shifts any more.

Another non-trivial aspect is that pte_modify() has to be changed
to preserve the _PAGE_PMD_HUGE bits as well as the page size field
of the pte.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No point in having this bit defined by architecture.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130917183629.090698799@linutronix.de

There is no reason for per arch hardirq bits. Make them all generic
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130917183628.534494408@linutronix.de

glibc recently changed the error string for ESTALE to remove "NFS" -

https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=96945714ec61951cc748da2b4b8a80cf02127ee9

from: [ERR_REMAP (ESTALE)] = N_("Stale NFS file handle"),
to:   [ERR_REMAP (ESTALE)] = N_("Stale file handle"),

And some have expressed concern that the kernel's errno.h
comments still refer to NFS.

So make that change... note that this is a comment-only change,
and has no functional difference.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

To make the page tables compact, we were using 32-bit PGDs and PMDs.
We only had to support <= 43 bits of physical addresses so this was
quite feasible.

In order to support larger physical addresses we have to move to
64-bit PGDs and PMDs.

Most of the changes are straight-forward:

1) {pgd,pmd}_t --> unsigned long

2) Anything that tries to use plain "unsigned int" types with pgd/pmd
   values needs to be adjusted.  In particular things like "0U" become
   "0UL".

3) {PGDIR,PMD}_BITS decrease by one.

4) In the assembler page table walkers, use "ldxa" instead of "lduwa"
   and adjust the low bit masks to clear out the low 3 bits instead of
   just the low 2 bits during pgd/pmd address formation.

Also, use PTRS_PER_PGD and PTRS_PER_PMD in the sizing of the
swapper_{pg_dir,low_pmd_dir} arrays.

This patch does not try to take advantage of having 64-bits in the
PMDs to simplify the hugepage code, that will come in a subsequent
change.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The impetus for this is that we would like to move to 64-bit PMDs and
PGDs, but that would result in only supporting a 42-bit address space
with the current page table layout.  It'd be nice to support at least
43-bits.

The reason we'd end up with only 42-bits after making PMDs and PGDs
64-bit is that we only use half-page sized PTE tables in order to make
PMDs line up to 4MB, the hardware huge page size we use.

So what we do here is we make huge pages 8MB, and fabricate them using
4MB hw TLB entries.

Facilitate this by providing a "REAL_HPAGE_SHIFT" which is used in
places that really need to operate on hardware 4MB pages.

Use full pages (512 entries) for PTE tables, and adjust PMD_SHIFT,
PGD_SHIFT, and the build time CPP test as needed.  Use a CPP test to
make sure REAL_HPAGE_SHIFT and the _PAGE_SZHUGE_* we use match up.

This makes the pgtable cache completely unused, so remove the code
managing it and the state used in mm_context_t.  Now we have less
spinlocks taken in the page table allocation path.

The technique we use to fabricate the 8MB pages is to transfer bit 22
from the missing virtual address into the PTEs physical address field.
That takes care of the transparent huge pages case.

For hugetlb, we fill things in at the PTE level and that code already
puts the sub huge page physical bits into the PTEs, based upon the
offset, so there is nothing special we need to do.  It all just works
out.

So, a small amount of complexity in the THP case, but this code is
about to get much simpler when we move the 64-bit PMDs as we can move
away from the fancy 32-bit huge PMD encoding and just put a real PTE
value in there.

With bug fixes and help from Bob Picco.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>