iris/userspace/glue/partition.ccp

#pypp 0
#include <iris.hh>
#include <devices.hh>

#define NUM_PARTITIONS 4
#define SECTOR_BITS 9
#define BLOCK_MASK (~((1 << SECTOR_BITS) - 1))

unsigned bits

struct Partition:
	static Iris::Num device_size
	unsigned lba_start, lba_size
	unsigned type
	bool active
	Iris::Num start, size
	static unsigned read_num (char *data):
		return data[0] & 0xff | (data[1] & 0xff) << 8 | (data[2] & 0xff) << 16 | (data[3] & 0xff) << 24
	void read (char *data):
		if data[0] == 0:
			active = false
		else:
			active = true
			if (data[0] & 0xff) != 0x80:
				kdebug ("Warning: invalid active code ")
				kdebug_num (data[0], 2)
				kdebug ("\n")
		type = data[4] & 0xff
		lba_start = read_num (data + 8)
		lba_size = read_num (data + 12)
		start = Iris::Num (lba_start).value () << SECTOR_BITS
		size = Iris::Num (lba_size).value () << SECTOR_BITS
		kdebug ("Partition read: ")
		kdebug_num (lba_start)
		kdebug ("+")
		kdebug_num (lba_size)
		kdebug ("\n")

Iris::Num Partition::device_size

static Iris::WBlock dev
static void read_sector (Iris::Num idx, Iris::Page page, unsigned size = 1 << SECTOR_BITS, unsigned offset = 0):
	offset &= ~PAGE_MASK
	if size + offset > PAGE_SIZE:
		size = PAGE_SIZE - offset
	size >>= SECTOR_BITS
	idx = idx.value () >> SECTOR_BITS
	for unsigned i = 0; i < size; ++i:
		dev.get_block ((idx.value () + i) << SECTOR_BITS, 1 << SECTOR_BITS, (i << SECTOR_BITS) + offset, page)

Iris::Num start ():
	Partition::device_size = 0
	dev = Iris::my_parent.get_capability <Iris::WBlock> ()
	bits = dev.get_align_bits ()
	if bits > SECTOR_BITS:
		Iris::panic (bits, "partitioned device doesn't support 512 byte access\n")
	Partition::device_size = dev.get_size ()
	Iris::Page page = Iris::my_memory.create_page ()
	page.set_flags (Iris::Page::PAYING)
	char *buffer = (char *)0x15000
	unsigned *ubuffer = (unsigned *)buffer
	Iris::my_memory.map (page, (unsigned)buffer)
	read_sector (0, page)

	if buffer[0x1fe] != 0x55 || (buffer[0x1ff] & 0xff) != 0xaa:
		kdebug ("invalid mbr signature\n")

	Partition partition[NUM_PARTITIONS]

	Iris::Cap cap
	for unsigned i = 0; i < NUM_PARTITIONS; ++i:
		partition[i].read (buffer + 0x1be + 0x10 * i)
		cap = Iris::my_receiver.create_capability (i)
		Iris::my_parent.provide_capability <Iris::WBlock> (cap.copy (), i)
		Iris::free_cap (cap)

	page.set_flags (0, Iris::Page::PAYING | Iris::Page::FRAME)

	Iris::my_parent.init_done ()

	while true:
		Iris::wait ()
		//kdebug ("partition received: ")
		//kdebug_num (Iris::recv.data[0].l)
		//kdebug ("\n")
		switch Iris::recv.data[0].l:
			case Iris::Block::GET_SIZE:
				Iris::recv.reply.invoke (partition[Iris::recv.protected_data.l].size)
				break
			case Iris::Block::GET_ALIGN_BITS:
				Iris::recv.reply.invoke (SECTOR_BITS)
				break
			case Iris::Block::GET_BLOCK:
				Iris::Cap reply = Iris::get_reply ()
				Iris::Cap arg = Iris::get_arg ()
				Iris::Num p = Iris::recv.data[1].value () & BLOCK_MASK
				Iris::Num offset = partition[Iris::recv.protected_data.l].start.value ()
				unsigned size = Iris::recv.data[0].h >> 16
				unsigned out_offset = Iris::recv.data[0].h & 0xffff
				//kdebug ("partition sending sector ")
				//kdebug_num (offset.h)
				//kdebug (":")
				//kdebug_num (offset.l)
				//kdebug (" + ")
				//kdebug_num (p.h)
				//kdebug (":")
				//kdebug_num (p.l)
				//kdebug (" = ")
				//kdebug_num (Iris::Num (offset.value () + p.value ()).h)
				//kdebug (":")
				//kdebug_num (Iris::Num (offset.value () + p.value ()).l)
				//kdebug ("\n")
				read_sector (offset.value () + p.value (), arg, size, out_offset)
				reply.invoke ()
				Iris::free_cap (reply)
				Iris::free_cap (arg)
				break
			case Iris::WBlock::SET_BLOCK:
				Iris::panic (Iris::recv.data[0].l, "writing to partitions not supported yet")
			case Iris::WBlock::TRUNCATE:
			default:
				Iris::panic (Iris::recv.data[0].l, "invalid request for partition handler")