mips: implement xor_unlock_is_negative_byte

Inspired by the mips test_and_change_bit(), this will surely be more
efficient than the generic one defined in filemap.c

Link: https://lkml.kernel.org/r/

mips: implement xor_unlock_is_negative_byte

Inspired by the mips test_and_change_bit(), this will surely be more
efficient than the generic one defined in filemap.c

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Cc: Albert Ou <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Andreas Dilger <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Ivan Kokshaysky <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Richard Henderson <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: "Theodore Ts'o" <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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MIPS: bitops: Use BIT_WORD() & BITS_PER_LONG

Rather than using custom SZLONG_LOG & SZLONG_MASK macros to shift & mask
a bit index to form word & bit offsets respectively, make use of the
standard BI

MIPS: bitops: Use BIT_WORD() & BITS_PER_LONG

Rather than using custom SZLONG_LOG & SZLONG_MASK macros to shift & mask
a bit index to form word & bit offsets respectively, make use of the
standard BIT_WORD() & BITS_PER_LONG macros for the same purpose.

volatile is added to the definition of pointers to the long-sized word
we'll operate on, in order to prevent the compiler complaining that we
cast away the volatile qualifier of the addr argument. This should have
no effect on generated code, which in the LL/SC case is inline asm
anyway & in the non-LLSC case access is constrained by compiler barriers
provided by raw_local_irq_{save,restore}().

Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: Huacai Chen <[email protected]>
Cc: Jiaxun Yang <[email protected]>
Cc: [email protected]

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MIPS: bitops: Implement test_and_set_bit() in terms of _lock variant

The only difference between test_and_set_bit() & test_and_set_bit_lock()
is memory ordering barrier semantics - the former provid

MIPS: bitops: Implement test_and_set_bit() in terms of _lock variant

The only difference between test_and_set_bit() & test_and_set_bit_lock()
is memory ordering barrier semantics - the former provides a full
barrier whilst the latter only provides acquire semantics.

We can therefore implement test_and_set_bit() in terms of
test_and_set_bit_lock() with the addition of the extra memory barrier.
Do this in order to avoid duplicating logic.

Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: Huacai Chen <[email protected]>
Cc: Jiaxun Yang <[email protected]>
Cc: [email protected]

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MIPS: Remove unneeded volatile from arch/mips/lib/bitops.c

The operations on the bitmap pointers are protected by "memory"
clobbering raw_local_irq_{save,restore}(), so there is no need for
volatile

MIPS: Remove unneeded volatile from arch/mips/lib/bitops.c

The operations on the bitmap pointers are protected by "memory"
clobbering raw_local_irq_{save,restore}(), so there is no need for
volatile here. By removing the volatile we get better code generation
out of the compiler.

Signed-off-by: David Daney <[email protected]>
Patchwork: http://patchwork.linux-mips.org/patch/4966/
Acked-by: John Crispin <[email protected]>

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MIPS: Fix logic errors in bitops.c

commit 92d11594f6 (MIPS: Remove irqflags.h dependency from bitops.h)
factored some of the bitops code out into a separate file
(arch/mips/lib/bitops.c). Unfortuna

MIPS: Fix logic errors in bitops.c

commit 92d11594f6 (MIPS: Remove irqflags.h dependency from bitops.h)
factored some of the bitops code out into a separate file
(arch/mips/lib/bitops.c). Unfortunately the logic converting a bit
mask into a boolean result was lost in some of the functions. We had:

int res;
unsigned long shifted_result_bit;
.
.
.
res = shifted_result_bit;
return res;

Which truncates off the high 32 bits (thus yielding an incorrect
value) on 64-bit systems.

The manifestation of this is that a non-SMP 64-bit kernel will not
boot as the bitmap operations in bootmem.c are all screwed up.

Signed-off-by: David Daney <[email protected]>
Cc: [email protected]
Cc: Jim Quinlan <[email protected]>
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/4965/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Whitespace cleanup.

Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-b

MIPS: Whitespace cleanup.

Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Remove irqflags.h dependency from bitops.h

The "else clause" of most functions in bitops.h invoked
raw_local_irq_{save,restore}() and in doing so had a dependency on
irqflags.h. This fix move

MIPS: Remove irqflags.h dependency from bitops.h

The "else clause" of most functions in bitops.h invoked
raw_local_irq_{save,restore}() and in doing so had a dependency on
irqflags.h. This fix moves said code to bitops.c, removing the
dependency.

Signed-off-by: Jim Quinlan <[email protected]>
Cc: [email protected]
Cc: David Daney <[email protected]>
Cc: Kevin Cernekee [email protected]
Cc: Jim Quinlan <[email protected]>
Patchwork: https://patchwork.linux-mips.org/patch/4320/
Signed-off-by: Ralf Baechle <[email protected]>

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