diff options
| author |   Kefeng Wang <wangkefeng.wang@huawei.com> | 2022-05-23 19:31:25 +0800 |
|---|---|---|
| committer |   Will Deacon <will@kernel.org> | 2022-06-23 18:34:58 +0100 |
| commit | ed59dfd9509d172e4920994ed9cbebf93b0050cc (patch) | |
| tree | 836859cb481958c930fc01482806bce7126ba36c /include/asm-generic | |
| parent | Linux 5.19-rc3 (diff) | |
| download | linux-dev-ed59dfd9509d172e4920994ed9cbebf93b0050cc.tar.xz linux-dev-ed59dfd9509d172e4920994ed9cbebf93b0050cc.zip | |
asm-generic: Add memory barrier dma_mb()
The memory barrier dma_mb() is introduced by commit a76a37777f2c
("iommu/arm-smmu-v3: Ensure queue is read after updating prod pointer"),
which is used to ensure that prior (both reads and writes) accesses
to memory by a CPU are ordered w.r.t. a subsequent MMIO write.
Reviewed-by: Arnd Bergmann <arnd@arndb.de> # for asm-generic
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20220523113126.171714-2-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'include/asm-generic')
| -rw-r--r-- | include/asm-generic/barrier.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h index fd7e8fbaeef1..961f4d88f9ef 100644 --- a/include/asm-generic/barrier.h +++ b/include/asm-generic/barrier.h @@ -38,6 +38,10 @@ #define wmb() do { kcsan_wmb(); __wmb(); } while (0) #endif +#ifdef __dma_mb +#define dma_mb() do { kcsan_mb(); __dma_mb(); } while (0) +#endif + #ifdef __dma_rmb #define dma_rmb() do { kcsan_rmb(); __dma_rmb(); } while (0) #endif @@ -65,6 +69,10 @@ #define wmb() mb() #endif +#ifndef dma_mb +#define dma_mb() mb() +#endif + #ifndef dma_rmb #define dma_rmb() rmb() #endif |