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[PATCH RFC 3/4] io-128-nonatomic: introduce io{read|write}128_{lo_hi|hi_lo}

Chenghai Huang posted 4 patches 2 months, 4 weeks ago
[PATCH RFC 3/4] io-128-nonatomic: introduce io{read|write}128_{lo_hi|hi_lo}
Posted by Chenghai Huang 2 months, 4 weeks ago 
From: Weili Qian <qianweili@huawei.com>

In order to provide non-atomic functions for io{read|write}128.
We define a number of variants of these functions in the generic
iomap that will do non-atomic operations.

These functions are only defined if io{read|write}128 are defined.
If they are not, then the wrappers that always use non-atomic operations
from include/linux/io-128-nonatomic*.h will be used.

Signed-off-by: Weili Qian <qianweili@huawei.com>
Signed-off-by: Chenghai Huang <huangchenghai2@huawei.com>
---
 include/linux/io-128-nonatomic-hi-lo.h | 35 ++++++++++++++++++++++++++
 include/linux/io-128-nonatomic-lo-hi.h | 34 +++++++++++++++++++++++++
 2 files changed, 69 insertions(+)
 create mode 100644 include/linux/io-128-nonatomic-hi-lo.h
 create mode 100644 include/linux/io-128-nonatomic-lo-hi.h

diff --git a/include/linux/io-128-nonatomic-hi-lo.h b/include/linux/io-128-nonatomic-hi-lo.h
new file mode 100644
index 000000000000..b5b083a9e81b
--- /dev/null
+++ b/include/linux/io-128-nonatomic-hi-lo.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_IO_128_NONATOMIC_HI_LO_H_
+#define _LINUX_IO_128_NONATOMIC_HI_LO_H_
+
+#include <linux/io.h>
+#include <asm-generic/int-ll64.h>
+
+static inline u128 ioread128_hi_lo(const void __iomem *addr)
+{
+	u32 low, high;
+
+	high = ioread64(addr + sizeof(u64));
+	low = ioread64(addr);
+
+	return low + ((u128)high << 64);
+}
+
+static inline void iowrite128_hi_lo(u128 val, void __iomem *addr)
+{
+	iowrite64(val >> 64, addr + sizeof(u64));
+	iowrite64(val, addr);
+}
+
+#ifndef ioread128
+#define ioread128_is_nonatomic
+#define ioread128 ioread128_hi_lo
+#endif
+
+#ifndef iowrite128
+#define iowrite128_is_nonatomic
+#define iowrite128 iowrite128_hi_lo
+#endif
+
+#endif	/* _LINUX_IO_128_NONATOMIC_HI_LO_H_ */
+
diff --git a/include/linux/io-128-nonatomic-lo-hi.h b/include/linux/io-128-nonatomic-lo-hi.h
new file mode 100644
index 000000000000..0448ee5a13de
--- /dev/null
+++ b/include/linux/io-128-nonatomic-lo-hi.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_IO_128_NONATOMIC_LO_HI_H_
+#define _LINUX_IO_128_NONATOMIC_LO_HI_H_
+
+#include <linux/io.h>
+#include <asm-generic/int-ll64.h>
+
+static inline u128 ioread128_lo_hi(const void __iomem *addr)
+{
+	u64 low, high;
+
+	low = ioread64(addr);
+	high = ioread64(addr + sizeof(u64));
+
+	return low + ((u128)high << 64);
+}
+
+static inline void iowrite128_lo_hi(u128 val, void __iomem *addr)
+{
+	iowrite64(val, addr);
+	iowrite64(val >> 64, addr + sizeof(u64));
+}
+
+#ifndef ioread128
+#define ioread128_is_nonatomic
+#define ioread128 ioread128_lo_hi
+#endif
+
+#ifndef iowrite128
+#define iowrite128_is_nonatomic
+#define iowrite128 iowrite128_lo_hi
+#endif
+
+#endif	/* _LINUX_IO_128_NONATOMIC_LO_HI_H_ */
-- 
2.33.0
Re: [PATCH RFC 3/4] io-128-nonatomic: introduce io{read|write}128_{lo_hi|hi_lo}
Posted by Ben Dooks 2 months, 4 weeks ago 
On 12/11/2025 01:58, Chenghai Huang wrote:
> From: Weili Qian <qianweili@huawei.com>
> 
> In order to provide non-atomic functions for io{read|write}128.
> We define a number of variants of these functions in the generic
> iomap that will do non-atomic operations.
> 
> These functions are only defined if io{read|write}128 are defined.
> If they are not, then the wrappers that always use non-atomic operations
> from include/linux/io-128-nonatomic*.h will be used.
> 
> Signed-off-by: Weili Qian <qianweili@huawei.com>
> Signed-off-by: Chenghai Huang <huangchenghai2@huawei.com>
> ---
>   include/linux/io-128-nonatomic-hi-lo.h | 35 ++++++++++++++++++++++++++
>   include/linux/io-128-nonatomic-lo-hi.h | 34 +++++++++++++++++++++++++
>   2 files changed, 69 insertions(+)
>   create mode 100644 include/linux/io-128-nonatomic-hi-lo.h
>   create mode 100644 include/linux/io-128-nonatomic-lo-hi.h
> 
> diff --git a/include/linux/io-128-nonatomic-hi-lo.h b/include/linux/io-128-nonatomic-hi-lo.h
> new file mode 100644
> index 000000000000..b5b083a9e81b
> --- /dev/null
> +++ b/include/linux/io-128-nonatomic-hi-lo.h
> @@ -0,0 +1,35 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _LINUX_IO_128_NONATOMIC_HI_LO_H_
> +#define _LINUX_IO_128_NONATOMIC_HI_LO_H_
> +
> +#include <linux/io.h>
> +#include <asm-generic/int-ll64.h>
> +
> +static inline u128 ioread128_hi_lo(const void __iomem *addr)
> +{
> +	u32 low, high;

did you mean u64 here?

> +	high = ioread64(addr + sizeof(u64));
> +	low = ioread64(addr);
> +
> +	return low + ((u128)high << 64);
> +}
> +
> +static inline void iowrite128_hi_lo(u128 val, void __iomem *addr)
> +{
> +	iowrite64(val >> 64, addr + sizeof(u64));
> +	iowrite64(val, addr);
> +}
> +

-- 
Ben Dooks				http://www.codethink.co.uk/
Senior Engineer				Codethink - Providing Genius

https://www.codethink.co.uk/privacy.html
Re: [PATCH RFC 3/4] io-128-nonatomic: introduce io{read|write}128_{lo_hi|hi_lo}
Posted by huangchenghai 2 months, 3 weeks ago 
在 2025/11/12 22:48, Ben Dooks 写道:
> On 12/11/2025 01:58, Chenghai Huang wrote:
>> From: Weili Qian <qianweili@huawei.com>
>>
>> In order to provide non-atomic functions for io{read|write}128.
>> We define a number of variants of these functions in the generic
>> iomap that will do non-atomic operations.
>>
>> These functions are only defined if io{read|write}128 are defined.
>> If they are not, then the wrappers that always use non-atomic operations
>> from include/linux/io-128-nonatomic*.h will be used.
>>
>> Signed-off-by: Weili Qian <qianweili@huawei.com>
>> Signed-off-by: Chenghai Huang <huangchenghai2@huawei.com>
>> ---
>>   include/linux/io-128-nonatomic-hi-lo.h | 35 ++++++++++++++++++++++++++
>>   include/linux/io-128-nonatomic-lo-hi.h | 34 +++++++++++++++++++++++++
>>   2 files changed, 69 insertions(+)
>>   create mode 100644 include/linux/io-128-nonatomic-hi-lo.h
>>   create mode 100644 include/linux/io-128-nonatomic-lo-hi.h
>>
>> diff --git a/include/linux/io-128-nonatomic-hi-lo.h 
>> b/include/linux/io-128-nonatomic-hi-lo.h
>> new file mode 100644
>> index 000000000000..b5b083a9e81b
>> --- /dev/null
>> +++ b/include/linux/io-128-nonatomic-hi-lo.h
>> @@ -0,0 +1,35 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +#ifndef _LINUX_IO_128_NONATOMIC_HI_LO_H_
>> +#define _LINUX_IO_128_NONATOMIC_HI_LO_H_
>> +
>> +#include <linux/io.h>
>> +#include <asm-generic/int-ll64.h>
>> +
>> +static inline u128 ioread128_hi_lo(const void __iomem *addr)
>> +{
>> +    u32 low, high;
>
> did you mean u64 here?
>
Thank you for your reminder, I made a rookie mistake.


Chenghai

>> +    high = ioread64(addr + sizeof(u64));
>> +    low = ioread64(addr);
>> +
>> +    return low + ((u128)high << 64);
>> +}
>> +
>> +static inline void iowrite128_hi_lo(u128 val, void __iomem *addr)
>> +{
>> +    iowrite64(val >> 64, addr + sizeof(u64));
>> +    iowrite64(val, addr);
>> +}
>> +
>

Patchew 2.1-devel-b67e4c2

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