2021-08-03 11:01:04

by Thomas Huth

[permalink] [raw]
Subject: [PATCH 1/2] sysctl: introduce new proc handler proc_dobool

From: Jia He <[email protected]>

This is to let bool variable could be correctly displayed in
big/little endian sysctl procfs. sizeof(bool) is arch dependent,
proc_dobool should work in all arches.

Suggested-by: Pan Xinhui <[email protected]>
Signed-off-by: Jia He <[email protected]>
[thuth: rebased the patch to the current kernel version]
Signed-off-by: Thomas Huth <[email protected]>
---
include/linux/sysctl.h | 2 ++
kernel/sysctl.c | 42 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 44 insertions(+)

diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index d99ca99837de..1fa2b69c6fc3 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -48,6 +48,8 @@ typedef int proc_handler(struct ctl_table *ctl, int write, void *buffer,
size_t *lenp, loff_t *ppos);

int proc_dostring(struct ctl_table *, int, void *, size_t *, loff_t *);
+int proc_dobool(struct ctl_table *table, int write, void *buffer,
+ size_t *lenp, loff_t *ppos);
int proc_dointvec(struct ctl_table *, int, void *, size_t *, loff_t *);
int proc_douintvec(struct ctl_table *, int, void *, size_t *, loff_t *);
int proc_dointvec_minmax(struct ctl_table *, int, void *, size_t *, loff_t *);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 272f4a272f8c..25e49b4d8049 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -536,6 +536,21 @@ static void proc_put_char(void **buf, size_t *size, char c)
}
}

+static int do_proc_dobool_conv(bool *negp, unsigned long *lvalp,
+ int *valp,
+ int write, void *data)
+{
+ if (write) {
+ *(bool *)valp = *lvalp;
+ } else {
+ int val = *(bool *)valp;
+
+ *lvalp = (unsigned long)val;
+ *negp = false;
+ }
+ return 0;
+}
+
static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
int *valp,
int write, void *data)
@@ -798,6 +813,26 @@ static int do_proc_douintvec(struct ctl_table *table, int write,
buffer, lenp, ppos, conv, data);
}

+/**
+ * proc_dobool - read/write a bool
+ * @table: the sysctl table
+ * @write: %TRUE if this is a write to the sysctl file
+ * @buffer: the user buffer
+ * @lenp: the size of the user buffer
+ * @ppos: file position
+ *
+ * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
+ * values from/to the user buffer, treated as an ASCII string.
+ *
+ * Returns 0 on success.
+ */
+int proc_dobool(struct ctl_table *table, int write, void *buffer,
+ size_t *lenp, loff_t *ppos)
+{
+ return do_proc_dointvec(table, write, buffer, lenp, ppos,
+ do_proc_dobool_conv, NULL);
+}
+
/**
* proc_dointvec - read a vector of integers
* @table: the sysctl table
@@ -1630,6 +1665,12 @@ int proc_dostring(struct ctl_table *table, int write,
return -ENOSYS;
}

+int proc_dobool(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ return -ENOSYS;
+}
+
int proc_dointvec(struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos)
{
@@ -3425,6 +3466,7 @@ int __init sysctl_init(void)
* No sense putting this after each symbol definition, twice,
* exception granted :-)
*/
+EXPORT_SYMBOL(proc_dobool);
EXPORT_SYMBOL(proc_dointvec);
EXPORT_SYMBOL(proc_douintvec);
EXPORT_SYMBOL(proc_dointvec_jiffies);
--
2.27.0



2021-08-18 09:41:00

by Thomas Huth

[permalink] [raw]
Subject: Re: [PATCH 1/2] sysctl: introduce new proc handler proc_dobool

On 03/08/2021 12.59, Thomas Huth wrote:
> From: Jia He <[email protected]>
>
> This is to let bool variable could be correctly displayed in
> big/little endian sysctl procfs. sizeof(bool) is arch dependent,
> proc_dobool should work in all arches.
>
> Suggested-by: Pan Xinhui <[email protected]>
> Signed-off-by: Jia He <[email protected]>
> [thuth: rebased the patch to the current kernel version]
> Signed-off-by: Thomas Huth <[email protected]>
> ---
> include/linux/sysctl.h | 2 ++
> kernel/sysctl.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 44 insertions(+)
>
> diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
> index d99ca99837de..1fa2b69c6fc3 100644
> --- a/include/linux/sysctl.h
> +++ b/include/linux/sysctl.h
> @@ -48,6 +48,8 @@ typedef int proc_handler(struct ctl_table *ctl, int write, void *buffer,
> size_t *lenp, loff_t *ppos);
>
> int proc_dostring(struct ctl_table *, int, void *, size_t *, loff_t *);
> +int proc_dobool(struct ctl_table *table, int write, void *buffer,
> + size_t *lenp, loff_t *ppos);
> int proc_dointvec(struct ctl_table *, int, void *, size_t *, loff_t *);
> int proc_douintvec(struct ctl_table *, int, void *, size_t *, loff_t *);
> int proc_dointvec_minmax(struct ctl_table *, int, void *, size_t *, loff_t *);
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 272f4a272f8c..25e49b4d8049 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -536,6 +536,21 @@ static void proc_put_char(void **buf, size_t *size, char c)
> }
> }
>
> +static int do_proc_dobool_conv(bool *negp, unsigned long *lvalp,
> + int *valp,
> + int write, void *data)
> +{
> + if (write) {
> + *(bool *)valp = *lvalp;
> + } else {
> + int val = *(bool *)valp;
> +
> + *lvalp = (unsigned long)val;
> + *negp = false;
> + }
> + return 0;
> +}
> +
> static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
> int *valp,
> int write, void *data)
> @@ -798,6 +813,26 @@ static int do_proc_douintvec(struct ctl_table *table, int write,
> buffer, lenp, ppos, conv, data);
> }
>
> +/**
> + * proc_dobool - read/write a bool
> + * @table: the sysctl table
> + * @write: %TRUE if this is a write to the sysctl file
> + * @buffer: the user buffer
> + * @lenp: the size of the user buffer
> + * @ppos: file position
> + *
> + * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
> + * values from/to the user buffer, treated as an ASCII string.
> + *
> + * Returns 0 on success.
> + */
> +int proc_dobool(struct ctl_table *table, int write, void *buffer,
> + size_t *lenp, loff_t *ppos)
> +{
> + return do_proc_dointvec(table, write, buffer, lenp, ppos,
> + do_proc_dobool_conv, NULL);
> +}
> +
> /**
> * proc_dointvec - read a vector of integers
> * @table: the sysctl table
> @@ -1630,6 +1665,12 @@ int proc_dostring(struct ctl_table *table, int write,
> return -ENOSYS;
> }
>
> +int proc_dobool(struct ctl_table *table, int write,
> + void *buffer, size_t *lenp, loff_t *ppos)
> +{
> + return -ENOSYS;
> +}
> +
> int proc_dointvec(struct ctl_table *table, int write,
> void *buffer, size_t *lenp, loff_t *ppos)
> {
> @@ -3425,6 +3466,7 @@ int __init sysctl_init(void)
> * No sense putting this after each symbol definition, twice,
> * exception granted :-)
> */
> +EXPORT_SYMBOL(proc_dobool);
> EXPORT_SYMBOL(proc_dointvec);
> EXPORT_SYMBOL(proc_douintvec);
> EXPORT_SYMBOL(proc_dointvec_jiffies);
>

Friendly ping!

Luis, Kees, Iurii, could you please have a look and provide an Ack if this
looks ok to you?

Thanks,
Thomas

2021-09-16 05:17:19

by Thomas Huth

[permalink] [raw]
Subject: Re: [PATCH 1/2] sysctl: introduce new proc handler proc_dobool

On 18/08/2021 11.38, Thomas Huth wrote:
> On 03/08/2021 12.59, Thomas Huth wrote:
>> From: Jia He <[email protected]>
>>
>> This is to let bool variable could be correctly displayed in
>> big/little endian sysctl procfs. sizeof(bool) is arch dependent,
>> proc_dobool should work in all arches.
>>
>> Suggested-by: Pan Xinhui <[email protected]>
>> Signed-off-by: Jia He <[email protected]>
>> [thuth: rebased the patch to the current kernel version]
>> Signed-off-by: Thomas Huth <[email protected]>
>> ---
>>   include/linux/sysctl.h |  2 ++
>>   kernel/sysctl.c        | 42 ++++++++++++++++++++++++++++++++++++++++++
>>   2 files changed, 44 insertions(+)
>>
>> diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
>> index d99ca99837de..1fa2b69c6fc3 100644
>> --- a/include/linux/sysctl.h
>> +++ b/include/linux/sysctl.h
>> @@ -48,6 +48,8 @@ typedef int proc_handler(struct ctl_table *ctl, int
>> write, void *buffer,
>>           size_t *lenp, loff_t *ppos);
>>   int proc_dostring(struct ctl_table *, int, void *, size_t *, loff_t *);
>> +int proc_dobool(struct ctl_table *table, int write, void *buffer,
>> +        size_t *lenp, loff_t *ppos);
>>   int proc_dointvec(struct ctl_table *, int, void *, size_t *, loff_t *);
>>   int proc_douintvec(struct ctl_table *, int, void *, size_t *, loff_t *);
>>   int proc_dointvec_minmax(struct ctl_table *, int, void *, size_t *,
>> loff_t *);
>> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
>> index 272f4a272f8c..25e49b4d8049 100644
>> --- a/kernel/sysctl.c
>> +++ b/kernel/sysctl.c
>> @@ -536,6 +536,21 @@ static void proc_put_char(void **buf, size_t *size,
>> char c)
>>       }
>>   }
>> +static int do_proc_dobool_conv(bool *negp, unsigned long *lvalp,
>> +                int *valp,
>> +                int write, void *data)
>> +{
>> +    if (write) {
>> +        *(bool *)valp = *lvalp;
>> +    } else {
>> +        int val = *(bool *)valp;
>> +
>> +        *lvalp = (unsigned long)val;
>> +        *negp = false;
>> +    }
>> +    return 0;
>> +}
>> +
>>   static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
>>                    int *valp,
>>                    int write, void *data)
>> @@ -798,6 +813,26 @@ static int do_proc_douintvec(struct ctl_table *table,
>> int write,
>>                      buffer, lenp, ppos, conv, data);
>>   }
>> +/**
>> + * proc_dobool - read/write a bool
>> + * @table: the sysctl table
>> + * @write: %TRUE if this is a write to the sysctl file
>> + * @buffer: the user buffer
>> + * @lenp: the size of the user buffer
>> + * @ppos: file position
>> + *
>> + * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
>> + * values from/to the user buffer, treated as an ASCII string.
>> + *
>> + * Returns 0 on success.
>> + */
>> +int proc_dobool(struct ctl_table *table, int write, void *buffer,
>> +        size_t *lenp, loff_t *ppos)
>> +{
>> +    return do_proc_dointvec(table, write, buffer, lenp, ppos,
>> +                do_proc_dobool_conv, NULL);
>> +}
>> +
>>   /**
>>    * proc_dointvec - read a vector of integers
>>    * @table: the sysctl table
>> @@ -1630,6 +1665,12 @@ int proc_dostring(struct ctl_table *table, int write,
>>       return -ENOSYS;
>>   }
>> +int proc_dobool(struct ctl_table *table, int write,
>> +        void *buffer, size_t *lenp, loff_t *ppos)
>> +{
>> +    return -ENOSYS;
>> +}
>> +
>>   int proc_dointvec(struct ctl_table *table, int write,
>>             void *buffer, size_t *lenp, loff_t *ppos)
>>   {
>> @@ -3425,6 +3466,7 @@ int __init sysctl_init(void)
>>    * No sense putting this after each symbol definition, twice,
>>    * exception granted :-)
>>    */
>> +EXPORT_SYMBOL(proc_dobool);
>>   EXPORT_SYMBOL(proc_dointvec);
>>   EXPORT_SYMBOL(proc_douintvec);
>>   EXPORT_SYMBOL(proc_dointvec_jiffies);
>>
>
> Friendly ping!
>
> Luis, Kees, Iurii, could you please have a look and provide an Ack if this
> looks ok to you?

Ping again!

Could anybody please provide an Ack?

Thanks,
Thomas