Commit e6d26bce authored by Yury Norov's avatar Yury Norov Committed by Yang Yingliang
Browse files

32-bit userspace ABI: introduce ARCH_32BIT_OFF_T config option 



hulk inclusion
category: feature
bugzilla: NA
CVE: NA
---------------------------

All new 32-bit architectures should have 64-bit userspace off_t type, but
existing architectures has 32-bit ones.

To enforce the rule, new config option is added to arch/Kconfig that
defaults ARCH_32BIT_OFF_T to be disabled for new 32-bit architectures.
All existing 32-bit architectures enable it explicitly.

New option affects force_o_largefile() behaviour. Namely, if userspace
off_t is 64-bits long, we have no reason to reject user to open big files.

Note that even if architectures has only 64-bit off_t in the kernel
(arc, c6x, h8300, hexagon, nios2, openrisc, and unicore32),
a libc may use 32-bit off_t, and therefore want to limit the file size
to 4GB unless specified differently in the open flags.

Signed-off-by: default avatarYury Norov <ynorov@caviumnetworks.com>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>

 Conflicts:
	arch/x86/um/Kconfig
[wangxiongfeng: conflicts in arch/x86/um/Kconfig. We only need to add
'select ARCH_32BIT_OFF_T' and ignore others. ]

Signed-off-by: default avatarXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: default avatarHanjun Guo &lt;guohanjun@huawei.com <mailto:guohanjun@huawei.com&gt;>
Signed-off-by: default avatarYang Yingliang <yangyingliang@huawei.com>
parent 680f1b10

arch/Kconfig

+15 −0
Original line number Diff line number Diff line
@@ -276,6 +276,21 @@ config ARCH_THREAD_STACK_ALLOCATOR 
config ARCH_WANTS_DYNAMIC_TASK_STRUCT

	bool



config ARCH_32BIT_OFF_T

	bool

	depends on !64BIT

	help

	  All new 32-bit architectures should have 64-bit off_t type on

	  userspace side which corresponds to the loff_t kernel type. This

	  is the requirement for modern ABIs. Some existing architectures

	  already have 32-bit off_t. This option is enabled for all such

	  architectures explicitly. Namely: arc, arm, blackfin, cris, frv,

	  h8300, hexagon, m32r, m68k, metag, microblaze, mips32, mn10300,

	  nios2, openrisc, parisc32, powerpc32, score, sh, sparc, tile32,

	  unicore32, x86_32 and xtensa. This is the complete list. Any

	  new 32-bit architecture should declare 64-bit off_t type on user

	  side and so should not enable this option.



config HAVE_REGS_AND_STACK_ACCESS_API

	bool

	help

arch/arc/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ config ARC 
	select ARCH_HAS_SYNC_DMA_FOR_DEVICE

	select ARCH_HAS_SG_CHAIN

	select ARCH_SUPPORTS_ATOMIC_RMW if ARC_HAS_LLSC

	select ARCH_32BIT_OFF_T

	select BUILDTIME_EXTABLE_SORT

	select CLONE_BACKWARDS

	select COMMON_CLK

arch/arm/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
config ARM

	bool

	default y

	select ARCH_32BIT_OFF_T

	select ARCH_CLOCKSOURCE_DATA

	select ARCH_DISCARD_MEMBLOCK if !HAVE_ARCH_PFN_VALID && !KEXEC

	select ARCH_HAS_DEBUG_VIRTUAL if MMU

arch/h8300/Kconfig

+1 −0
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0

config H8300

        def_bool y

	select ARCH_32BIT_OFF_T

	select GENERIC_ATOMIC64

	select HAVE_UID16

	select VIRT_TO_BUS

arch/hexagon/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ comment "Linux Kernel Configuration for Hexagon" 


config HEXAGON

	def_bool y

	select ARCH_32BIT_OFF_T

	select ARCH_NO_PREEMPT

	select HAVE_OPROFILE

	# Other pending projects/to-do items.