Re: [PATCH v4 04/11] fs: Add initial atomic write support info to statx

John Garry
2024-02-20T09:43:29Z

On 19/02/2024 22:28, Dave Chinner wrote:
>>
>> +/**
>> + * generic_fill_statx_atomic_writes - Fill in the atomic writes statx attributes
>> + * @stat: Where to fill in the attribute flags
>> + * @unit_min: Minimum supported atomic write length
>> + * @unit_max: Maximum supported atomic write length
>> + *
>> + * Fill in the STATX{_ATTR}_WRITE_ATOMIC flags in the kstat structure from
>> + * atomic write unit_min and unit_max values.
>> + */
>> +void generic_fill_statx_atomic_writes(struct kstat *stat,
>> + unsigned int unit_min,
>> + unsigned int unit_max)
>> +{
>> + /* Confirm that the request type is known */
>> + stat->result_mask |= STATX_WRITE_ATOMIC;
>> +
>> + /* Confirm that the file attribute type is known */
>> + stat->attributes_mask |= STATX_ATTR_WRITE_ATOMIC;
>> +
>> + if (unit_min) {
>> + stat->atomic_write_unit_min = unit_min;
>> + stat->atomic_write_unit_max = unit_max;
>> + /* Initially only allow 1x segment */
>> + stat->atomic_write_segments_max = 1;
>> +
>> + /* Confirm atomic writes are actually supported */
>> + stat->attributes |= STATX_ATTR_WRITE_ATOMIC;
>> + }
>> +}
>> +EXPORT_SYMBOL(generic_fill_statx_atomic_writes);
> What units are these in? Nothing in the patch or commit description
> tells us....

I can append the current comments to mention that the unit is bytes.

Thanks,
John