raid-0,raid-1 help

Hello,

I need some help in understanding the linux raid-0 and raid-1.
If in raid-0 , i have two device (/dev/sda and /dev/sdb and the chunk size is 4k, which part of the code is responsible for deciding that the first 4k goes into /dev/sda and then second write of 4K goes into /dev/sdb.How does md driver knows the layout of the disk. Does it leave to the ide or scsi driver.

Also while reading the data, it needs to read from /dev/sda first and then from /dev/sdb. which routine is responsible for tracking the blocks and lba.

also Which routine is responsible for queuing the md driver data and command.

where can i find the documentation for raid source code.

All help appreciated.

Thanks
Jay

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