void VirtioBlk::irq_handler() {
debug2("<VirtioBlk> IRQ handler\n");
//Virtio Std. § 4.1.5.5, steps 1-3
// Step 1. read ISR
unsigned char isr = hw::inp(iobase() + VIRTIO_PCI_ISR);
// Step 2. A) - one of the queues have changed
if (isr & 1) {
// This now means service RX & TX interchangeably
service_RX();
}
// Step 2. B)
if (isr & 2) {
debug("\t <VirtioBlk> Configuration change:\n");
// Getting the MAC + status
//debug("\t Old status: 0x%x\n", config.status);
get_config();
//debug("\t New status: 0x%x \n", config.status);
}
}
VirtioBlk::VirtioBlk(hw::PCI_Device& d)
: Virtio(d), hw::Drive(), req(queue_size(0), 0, iobase()), inflight(0)
{
INFO("VirtioBlk", "Driver initializing");
{
auto& reqs = Statman::get().create(
Stat::UINT32, blkname() + ".requests");
this->requests = &reqs.get_uint32();
*this->requests = 0;
auto& err = Statman::get().create(
Stat::UINT32, blkname() + ".errors");
this->errors = &err.get_uint32();
*this->errors = 0;
}
uint32_t needed_features =
FEAT(VIRTIO_BLK_F_BLK_SIZE);
negotiate_features(needed_features);
CHECK(features() & FEAT(VIRTIO_BLK_F_BARRIER),
"Barrier is enabled");
CHECK(features() & FEAT(VIRTIO_BLK_F_SIZE_MAX),
"Size-max is known");
CHECK(features() & FEAT(VIRTIO_BLK_F_SEG_MAX),
"Seg-max is known");
CHECK(features() & FEAT(VIRTIO_BLK_F_GEOMETRY),
"Geometry structure is used");
CHECK(features() & FEAT(VIRTIO_BLK_F_RO),
"Device is read-only");
CHECK(features() & FEAT(VIRTIO_BLK_F_BLK_SIZE),
"Block-size is known");
CHECK(features() & FEAT(VIRTIO_BLK_F_SCSI),
"SCSI is enabled :(");
CHECK(features() & FEAT(VIRTIO_BLK_F_FLUSH),
"Flush enabled");
CHECK ((features() & needed_features) == needed_features,
"Negotiated needed features");
// Step 1 - Initialize REQ queue
auto success = assign_queue(0, (uint32_t) req.queue_desc());
CHECK(success, "Request queue assigned (0x%x) to device",
(uint32_t) req.queue_desc());
// Step 3 - Fill receive queue with buffers
// DEBUG: Disable
INFO("VirtioBlk", "Queue size: %i\tRequest size: %u\n",
req.size(), sizeof(request_t));
// Get device configuration
get_config();
// Signal setup complete.
setup_complete((features() & needed_features) == needed_features);
CHECK((features() & needed_features) == needed_features, "Signalled driver OK");
// Hook up IRQ handler (inherited from Virtio)
if (is_msix())
{
// update IRQ subscriptions
IRQ_manager::get().subscribe(irq() + 0, {this, &VirtioBlk::service_RX});
IRQ_manager::get().subscribe(irq() + 1, {this, &VirtioBlk::msix_conf_handler});
}
else
{
auto del(delegate<void()>{this, &VirtioBlk::irq_handler});
IRQ_manager::get().subscribe(irq(), del);
}
// Done
INFO("VirtioBlk", "Block device with %llu sectors capacity", config.capacity);
}
bool Virtio::assign_queue(uint16_t index, uint32_t queue_desc){
hw::outpw(iobase() + VIRTIO_PCI_QUEUE_SEL, index);
hw::outpd(iobase() + VIRTIO_PCI_QUEUE_PFN, OS::page_nr_from_addr(queue_desc));
return hw::inpd(iobase() + VIRTIO_PCI_QUEUE_PFN) == OS::page_nr_from_addr(queue_desc);
}
uint32_t Virtio::queue_size(uint16_t index){
hw::outpw(iobase() + VIRTIO_PCI_QUEUE_SEL, index);
return hw::inpw(iobase() + VIRTIO_PCI_QUEUE_SIZE);
}
