Allocation unit size as option

[Liryna]

We should be able to set the allocation unit size of the device as a DokanOption or during the Mount.
DOKAN_ALLOCATION_UNIT_SIZE DOKAN_SECTOR_SIZE
The value should also be checked to fit the windows FAT/NTFS value:
https://support.microsoft.com/en-us/kb/140365

[Liryna]

Hi @marinkobabic ,

I am currently looking for this ticket to integrate it in the 1.0.0.

I was thinking that DOKAN_SECTOR_SIZE was only used in the library but it seems like in the kernel also...

dokany/sys/device.c

Line 104 in e370ff8

DOKAN_DISK_SIZE / DOKAN_SECTOR_SIZE / 32 / 2;

dokany/sys/device.c

Line 232 in e370ff8

DOKAN_DISK_SIZE; // Partition size equels disk size here

For me the DokanPopulateDiskGeometry and DiskDeviceControl are strange because they use DOKAN_DISK_SIZE that could be incorrect if the user has set his own size.

Do you think the values should be updated ? for now it don't seems to create an issue 😄

[Liryna]

See https://github.com/dokan-dev/dokany/compare/ClusterSizeOption?expand=1 with the current changes

[marinkobabic]

@Liryna You are right, but the information is displayed in explorer is the volume size which is updated by the user. Makes not a big difference if you update the disk information or not. Usually a volume can be created over one or more disks.

[Liryna]

Thank you for your input @marinkobabic !
Therefore I have changed nothing in the kernel.

This has been done and can be tested with mirror option by creating a file with 1 byte and observing the real file size changing depending of the value used.
4ab27c6