Method hotplug_ram_region

vmm/src/memory_manager.rs:2206–2252

(&mut self, size: usize)

    }

    fn hotplug_ram_region(&mut self, size: usize) -> Result<Arc<GuestRegionMmap>, Error> {
        info!("Hotplugging new RAM: {size}");

        // Check that there is a free slot
        if self.next_hotplug_slot >= HOTPLUG_COUNT {
            return Err(Error::NoSlotAvailable);
        }

        // "Inserted" DIMM must have a size that is a multiple of 128MiB
        if !size.is_multiple_of(128 << 20) {
            return Err(Error::InvalidSize);
        }

        let start_addr = MemoryManager::start_addr(self.guest_memory.memory().last_addr(), true)?;

        if start_addr
            .checked_add((size - 1).try_into().unwrap())
            .unwrap()
            > self.end_of_ram_area
        {
            return Err(Error::InsufficientHotplugRam);
        }

        let region = self.add_ram_region(start_addr, size)?;

        // Add region to the list of regions associated with the default
        // memory zone.
        if let Some(memory_zone) = self.memory_zones.get_mut(DEFAULT_MEMORY_ZONE) {
            memory_zone.regions.push(Arc::clone(&region));
        }

        // Tell the allocator
        self.ram_allocator
            .allocate(Some(start_addr), size as GuestUsize, None)
            .ok_or(Error::MemoryRangeAllocation)?;

        // Update the slot so that it can be queried via the I/O port
        let slot = &mut self.hotplug_slots[self.next_hotplug_slot];
        slot.active = true;
        slot.inserting = true;
        slot.base = region.start_addr().0;
        slot.length = region.len();

        self.next_hotplug_slot += 1;

        Ok(region)
    }

    pub fn guest_memory(&self) -> GuestMemoryAtomic<GuestMemoryMmap> {
        self.guest_memory.clone()