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authorChristoph Hellwig <hch@lst.de>2018-11-09 09:51:00 +0100
committerChristoph Hellwig <hch@lst.de>2018-12-06 07:04:56 -0800
commit7c703e54cc71df5baa962e24a5663d88173bba5c (patch)
treecaf54e62471ee960c1143a58d246d2e63bd35616
parentdma-mapping: return an error code from dma_mapping_error (diff)
downloadlinux-dev-7c703e54cc71df5baa962e24a5663d88173bba5c.tar.xz
linux-dev-7c703e54cc71df5baa962e24a5663d88173bba5c.zip
arch: switch the default on ARCH_HAS_SG_CHAIN
These days architectures are mostly out of the business of dealing with struct scatterlist at all, unless they have architecture specific iommu drivers. Replace the ARCH_HAS_SG_CHAIN symbol with a ARCH_NO_SG_CHAIN one only enabled for architectures with horrible legacy iommu drivers like alpha and parisc, and conditionally for arm which wants to keep it disable for legacy platforms. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Diffstat (limited to '')
-rw-r--r--Documentation/features/io/sg-chain/arch-support.txt33
-rw-r--r--arch/alpha/Kconfig1
-rw-r--r--arch/arc/Kconfig1
-rw-r--r--arch/arm/Kconfig2
-rw-r--r--arch/arm64/Kconfig1
-rw-r--r--arch/ia64/Kconfig1
-rw-r--r--arch/parisc/Kconfig1
-rw-r--r--arch/powerpc/Kconfig1
-rw-r--r--arch/s390/Kconfig1
-rw-r--r--arch/sparc/Kconfig1
-rw-r--r--arch/x86/Kconfig1
-rw-r--r--arch/xtensa/Kconfig1
-rw-r--r--include/linux/scatterlist.h6
-rw-r--r--lib/Kconfig2
-rw-r--r--lib/scatterlist.c2
15 files changed, 8 insertions, 47 deletions
diff --git a/Documentation/features/io/sg-chain/arch-support.txt b/Documentation/features/io/sg-chain/arch-support.txt
deleted file mode 100644
index 6554f0372c3f..000000000000
--- a/Documentation/features/io/sg-chain/arch-support.txt
+++ /dev/null
@@ -1,33 +0,0 @@
-#
-# Feature name: sg-chain
-# Kconfig: ARCH_HAS_SG_CHAIN
-# description: arch supports chained scatter-gather lists
-#
- -----------------------
- | arch |status|
- -----------------------
- | alpha: | TODO |
- | arc: | ok |
- | arm: | ok |
- | arm64: | ok |
- | c6x: | TODO |
- | h8300: | TODO |
- | hexagon: | TODO |
- | ia64: | ok |
- | m68k: | TODO |
- | microblaze: | TODO |
- | mips: | TODO |
- | nds32: | TODO |
- | nios2: | TODO |
- | openrisc: | TODO |
- | parisc: | TODO |
- | powerpc: | ok |
- | riscv: | TODO |
- | s390: | ok |
- | sh: | TODO |
- | sparc: | ok |
- | um: | TODO |
- | unicore32: | TODO |
- | x86: | ok |
- | xtensa: | TODO |
- -----------------------
diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index 5b4f88363453..a7e748a46c18 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -5,6 +5,7 @@ config ALPHA
select ARCH_MIGHT_HAVE_PC_PARPORT
select ARCH_MIGHT_HAVE_PC_SERIO
select ARCH_NO_PREEMPT
+ select ARCH_NO_SG_CHAIN
select ARCH_USE_CMPXCHG_LOCKREF
select HAVE_AOUT
select HAVE_IDE
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index c9e2a1323536..fd48d698da29 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -13,7 +13,6 @@ config ARC
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SYNC_DMA_FOR_CPU
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
- select ARCH_HAS_SG_CHAIN
select ARCH_SUPPORTS_ATOMIC_RMW if ARC_HAS_LLSC
select BUILDTIME_EXTABLE_SORT
select CLONE_BACKWARDS
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 3b2852df6eb3..a858ee791ef0 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -19,6 +19,7 @@ config ARM
select ARCH_HAVE_CUSTOM_GPIO_H
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_MIGHT_HAVE_PC_PARPORT
+ select ARCH_NO_SG_CHAIN if !ARM_HAS_SG_CHAIN
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
select ARCH_SUPPORTS_ATOMIC_RMW
@@ -119,7 +120,6 @@ config ARM
<http://www.arm.linux.org.uk/>.
config ARM_HAS_SG_CHAIN
- select ARCH_HAS_SG_CHAIN
bool
config ARM_DMA_USE_IOMMU
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 2e645ea693ea..06cf0ef24367 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -23,7 +23,6 @@ config ARM64
select ARCH_HAS_MEMBARRIER_SYNC_CORE
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SET_MEMORY
- select ARCH_HAS_SG_CHAIN
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 36773def6920..d6f203658994 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -29,7 +29,6 @@ config IA64
select HAVE_MEMBLOCK_NODE_MAP
select HAVE_VIRT_CPU_ACCOUNTING
select ARCH_HAS_DMA_MARK_CLEAN
- select ARCH_HAS_SG_CHAIN
select VIRT_TO_BUS
select ARCH_DISCARD_MEMBLOCK
select GENERIC_IRQ_PROBE
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 92a339ee28b3..428ee50fc3db 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -11,6 +11,7 @@ config PARISC
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_NO_SG_CHAIN
select ARCH_SUPPORTS_MEMORY_FAILURE
select RTC_CLASS
select RTC_DRV_GENERIC
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 8be31261aec8..4bc8edd83cee 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -138,7 +138,6 @@ config PPC
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_MEMBARRIER_CALLBACKS
select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE && PPC64
- select ARCH_HAS_SG_CHAIN
select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !RELOCATABLE && !HIBERNATION)
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UACCESS_FLUSHCACHE if PPC64
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 5173366af8f3..5624e8607054 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -73,7 +73,6 @@ config S390
select ARCH_HAS_KCOV
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SET_MEMORY
- select ARCH_HAS_SG_CHAIN
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_UBSAN_SANITIZE_ALL
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 490b2c95c212..8853b6ceae17 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -40,7 +40,6 @@ config SPARC
select MODULES_USE_ELF_RELA
select ODD_RT_SIGACTION
select OLD_SIGSUSPEND
- select ARCH_HAS_SG_CHAIN
select CPU_NO_EFFICIENT_FFS
select LOCKDEP_SMALL if LOCKDEP
select NEED_DMA_MAP_STATE
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 9d734f3c8234..adc845b66f01 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -66,7 +66,6 @@ config X86
select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
select ARCH_HAS_SET_MEMORY
- select ARCH_HAS_SG_CHAIN
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 239bfb16c58b..75488b606edc 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -1,7 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
config XTENSA
def_bool y
- select ARCH_HAS_SG_CHAIN
select ARCH_HAS_SYNC_DMA_FOR_CPU
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select ARCH_NO_COHERENT_DMA_MMAP if !MMU
diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h
index 093aa57120b0..b96f0d0b5b8f 100644
--- a/include/linux/scatterlist.h
+++ b/include/linux/scatterlist.h
@@ -324,10 +324,10 @@ size_t sg_zero_buffer(struct scatterlist *sgl, unsigned int nents,
* Like SG_CHUNK_SIZE, but for archs that have sg chaining. This limit
* is totally arbitrary, a setting of 2048 will get you at least 8mb ios.
*/
-#ifdef CONFIG_ARCH_HAS_SG_CHAIN
-#define SG_MAX_SEGMENTS 2048
-#else
+#ifdef CONFIG_ARCH_NO_SG_CHAIN
#define SG_MAX_SEGMENTS SG_CHUNK_SIZE
+#else
+#define SG_MAX_SEGMENTS 2048
#endif
#ifdef CONFIG_SG_POOL
diff --git a/lib/Kconfig b/lib/Kconfig
index a9965f4af4dd..d5a5e2ebf286 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -577,7 +577,7 @@ config SG_POOL
# sg chaining option
#
-config ARCH_HAS_SG_CHAIN
+config ARCH_NO_SG_CHAIN
def_bool n
config ARCH_HAS_PMEM_API
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index 7c6096a71704..9ba349e775ef 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -271,7 +271,7 @@ int __sg_alloc_table(struct sg_table *table, unsigned int nents,
if (nents == 0)
return -EINVAL;
-#ifndef CONFIG_ARCH_HAS_SG_CHAIN
+#ifdef CONFIG_ARCH_NO_SG_CHAIN
if (WARN_ON_ONCE(nents > max_ents))
return -EINVAL;
#endif