diff --git a/vmbase/src/memory/dbm.rs b/vmbase/src/memory/dbm.rs
index a7118bb..d429b30 100644
--- a/vmbase/src/memory/dbm.rs
+++ b/vmbase/src/memory/dbm.rs
@@ -21,7 +21,7 @@
 
 /// Sets whether the hardware management of access and dirty state is enabled with
 /// the given boolean.
-pub fn set_dbm_enabled(enabled: bool) {
+pub(super) fn set_dbm_enabled(enabled: bool) {
     if !dbm_available() {
         return;
     }
@@ -50,10 +50,7 @@
 }
 
 /// Flushes a memory range the descriptor refers to, if the descriptor is in writable-dirty state.
-/// As the return type is required by the crate `aarch64_paging`, we cannot address the lint
-/// issue `clippy::result_unit_err`.
-#[allow(clippy::result_unit_err)]
-pub fn flush_dirty_range(
+pub(super) fn flush_dirty_range(
     va_range: &MemoryRegion,
     desc: &mut Descriptor,
     level: usize,
@@ -71,10 +68,7 @@
 
 /// Clears read-only flag on a PTE, making it writable-dirty. Used when dirty state is managed
 /// in software to handle permission faults on read-only descriptors.
-/// As the return type is required by the crate `aarch64_paging`, we cannot address the lint
-/// issue `clippy::result_unit_err`.
-#[allow(clippy::result_unit_err)]
-pub fn mark_dirty_block(
+pub(super) fn mark_dirty_block(
     va_range: &MemoryRegion,
     desc: &mut Descriptor,
     level: usize,
diff --git a/vmbase/src/memory/mod.rs b/vmbase/src/memory/mod.rs
index f919bcd..9f14691 100644
--- a/vmbase/src/memory/mod.rs
+++ b/vmbase/src/memory/mod.rs
@@ -20,10 +20,9 @@
 mod shared;
 mod util;
 
-pub use dbm::{flush_dirty_range, mark_dirty_block, set_dbm_enabled};
 pub use error::MemoryTrackerError;
 pub use page_table::PageTable;
-pub use shared::{mmio_guard_unmap_page, verify_lazy_mapped_block, MemorySharer};
+pub use shared::{alloc_shared, dealloc_shared, MemoryRange, MemoryTracker, MEMORY};
 pub use util::{
     flush, flushed_zeroize, min_dcache_line_size, page_4kb_of, phys_to_virt, virt_to_phys,
     PAGE_SIZE, SIZE_2MB, SIZE_4KB, SIZE_4MB,
diff --git a/vmbase/src/memory/shared.rs b/vmbase/src/memory/shared.rs
index 5284e30..1413c60 100644
--- a/vmbase/src/memory/shared.rs
+++ b/vmbase/src/memory/shared.rs
@@ -14,22 +14,346 @@
 
 //! Shared memory management.
 
-use super::page_table::{is_leaf_pte, MMIO_LAZY_MAP_FLAG};
-use super::util::virt_to_phys;
+use super::dbm::{flush_dirty_range, mark_dirty_block, set_dbm_enabled};
+use super::error::MemoryTrackerError;
+use super::page_table::{is_leaf_pte, PageTable, MMIO_LAZY_MAP_FLAG};
+use super::util::{page_4kb_of, virt_to_phys};
+use crate::dsb;
+use crate::util::RangeExt as _;
 use aarch64_paging::paging::{Attributes, Descriptor, MemoryRegion as VaRange};
 use alloc::alloc::{alloc_zeroed, dealloc, handle_alloc_error};
+use alloc::boxed::Box;
 use alloc::vec::Vec;
-use buddy_system_allocator::FrameAllocator;
+use buddy_system_allocator::{FrameAllocator, LockedFrameAllocator};
 use core::alloc::Layout;
+use core::iter::once;
+use core::num::NonZeroUsize;
+use core::ops::Range;
 use core::ptr::NonNull;
 use core::result;
 use hyp::{get_hypervisor, MMIO_GUARD_GRANULE_SIZE};
-use log::{error, trace};
+use log::{debug, error, trace};
+use once_cell::race::OnceBox;
+use spin::mutex::SpinMutex;
+use tinyvec::ArrayVec;
+
+/// A global static variable representing the system memory tracker, protected by a spin mutex.
+pub static MEMORY: SpinMutex<Option<MemoryTracker>> = SpinMutex::new(None);
+
+static SHARED_POOL: OnceBox<LockedFrameAllocator<32>> = OnceBox::new();
+static SHARED_MEMORY: SpinMutex<Option<MemorySharer>> = SpinMutex::new(None);
+
+/// Memory range.
+pub type MemoryRange = Range<usize>;
+type Result<T> = result::Result<T, MemoryTrackerError>;
+
+#[derive(Clone, Copy, Debug, Default, PartialEq)]
+enum MemoryType {
+    #[default]
+    ReadOnly,
+    ReadWrite,
+}
+
+#[derive(Clone, Debug, Default)]
+struct MemoryRegion {
+    range: MemoryRange,
+    mem_type: MemoryType,
+}
+
+/// Tracks non-overlapping slices of main memory.
+pub struct MemoryTracker {
+    total: MemoryRange,
+    page_table: PageTable,
+    regions: ArrayVec<[MemoryRegion; MemoryTracker::CAPACITY]>,
+    mmio_regions: ArrayVec<[MemoryRange; MemoryTracker::MMIO_CAPACITY]>,
+    mmio_range: MemoryRange,
+    payload_range: MemoryRange,
+}
+
+unsafe impl Send for MemoryTracker {}
+
+impl MemoryTracker {
+    const CAPACITY: usize = 5;
+    const MMIO_CAPACITY: usize = 5;
+
+    /// Creates a new instance from an active page table, covering the maximum RAM size.
+    pub fn new(
+        mut page_table: PageTable,
+        total: MemoryRange,
+        mmio_range: MemoryRange,
+        payload_range: MemoryRange,
+    ) -> Self {
+        assert!(
+            !total.overlaps(&mmio_range),
+            "MMIO space should not overlap with the main memory region."
+        );
+
+        // Activate dirty state management first, otherwise we may get permission faults immediately
+        // after activating the new page table. This has no effect before the new page table is
+        // activated because none of the entries in the initial idmap have the DBM flag.
+        set_dbm_enabled(true);
+
+        debug!("Activating dynamic page table...");
+        // SAFETY - page_table duplicates the static mappings for everything that the Rust code is
+        // aware of so activating it shouldn't have any visible effect.
+        unsafe { page_table.activate() }
+        debug!("... Success!");
+
+        Self {
+            total,
+            page_table,
+            regions: ArrayVec::new(),
+            mmio_regions: ArrayVec::new(),
+            mmio_range,
+            payload_range,
+        }
+    }
+
+    /// Resize the total RAM size.
+    ///
+    /// This function fails if it contains regions that are not included within the new size.
+    pub fn shrink(&mut self, range: &MemoryRange) -> Result<()> {
+        if range.start != self.total.start {
+            return Err(MemoryTrackerError::DifferentBaseAddress);
+        }
+        if self.total.end < range.end {
+            return Err(MemoryTrackerError::SizeTooLarge);
+        }
+        if !self.regions.iter().all(|r| r.range.is_within(range)) {
+            return Err(MemoryTrackerError::SizeTooSmall);
+        }
+
+        self.total = range.clone();
+        Ok(())
+    }
+
+    /// Allocate the address range for a const slice; returns None if failed.
+    pub fn alloc_range(&mut self, range: &MemoryRange) -> Result<MemoryRange> {
+        let region = MemoryRegion { range: range.clone(), mem_type: MemoryType::ReadOnly };
+        self.check(&region)?;
+        self.page_table.map_rodata(range).map_err(|e| {
+            error!("Error during range allocation: {e}");
+            MemoryTrackerError::FailedToMap
+        })?;
+        self.add(region)
+    }
+
+    /// Allocate the address range for a mutable slice; returns None if failed.
+    pub fn alloc_range_mut(&mut self, range: &MemoryRange) -> Result<MemoryRange> {
+        let region = MemoryRegion { range: range.clone(), mem_type: MemoryType::ReadWrite };
+        self.check(&region)?;
+        self.page_table.map_data_dbm(range).map_err(|e| {
+            error!("Error during mutable range allocation: {e}");
+            MemoryTrackerError::FailedToMap
+        })?;
+        self.add(region)
+    }
+
+    /// Allocate the address range for a const slice; returns None if failed.
+    pub fn alloc(&mut self, base: usize, size: NonZeroUsize) -> Result<MemoryRange> {
+        self.alloc_range(&(base..(base + size.get())))
+    }
+
+    /// Allocate the address range for a mutable slice; returns None if failed.
+    pub fn alloc_mut(&mut self, base: usize, size: NonZeroUsize) -> Result<MemoryRange> {
+        self.alloc_range_mut(&(base..(base + size.get())))
+    }
+
+    /// Checks that the given range of addresses is within the MMIO region, and then maps it
+    /// appropriately.
+    pub fn map_mmio_range(&mut self, range: MemoryRange) -> Result<()> {
+        if !range.is_within(&self.mmio_range) {
+            return Err(MemoryTrackerError::OutOfRange);
+        }
+        if self.mmio_regions.iter().any(|r| range.overlaps(r)) {
+            return Err(MemoryTrackerError::Overlaps);
+        }
+        if self.mmio_regions.len() == self.mmio_regions.capacity() {
+            return Err(MemoryTrackerError::Full);
+        }
+
+        self.page_table.map_device_lazy(&range).map_err(|e| {
+            error!("Error during MMIO device mapping: {e}");
+            MemoryTrackerError::FailedToMap
+        })?;
+
+        if self.mmio_regions.try_push(range).is_some() {
+            return Err(MemoryTrackerError::Full);
+        }
+
+        Ok(())
+    }
+
+    /// Checks that the given region is within the range of the `MemoryTracker` and doesn't overlap
+    /// with any other previously allocated regions, and that the regions ArrayVec has capacity to
+    /// add it.
+    fn check(&self, region: &MemoryRegion) -> Result<()> {
+        if !region.range.is_within(&self.total) {
+            return Err(MemoryTrackerError::OutOfRange);
+        }
+        if self.regions.iter().any(|r| region.range.overlaps(&r.range)) {
+            return Err(MemoryTrackerError::Overlaps);
+        }
+        if self.regions.len() == self.regions.capacity() {
+            return Err(MemoryTrackerError::Full);
+        }
+        Ok(())
+    }
+
+    fn add(&mut self, region: MemoryRegion) -> Result<MemoryRange> {
+        if self.regions.try_push(region).is_some() {
+            return Err(MemoryTrackerError::Full);
+        }
+
+        Ok(self.regions.last().unwrap().range.clone())
+    }
+
+    /// Unmaps all tracked MMIO regions from the MMIO guard.
+    ///
+    /// Note that they are not unmapped from the page table.
+    pub fn mmio_unmap_all(&mut self) -> Result<()> {
+        for range in &self.mmio_regions {
+            self.page_table
+                .modify_range(range, &mmio_guard_unmap_page)
+                .map_err(|_| MemoryTrackerError::FailedToUnmap)?;
+        }
+        Ok(())
+    }
+
+    /// Initialize the shared heap to dynamically share memory from the global allocator.
+    pub fn init_dynamic_shared_pool(&mut self) -> Result<()> {
+        const INIT_CAP: usize = 10;
+
+        let granule = get_hypervisor().memory_protection_granule()?;
+        let previous = SHARED_MEMORY.lock().replace(MemorySharer::new(granule, INIT_CAP));
+        if previous.is_some() {
+            return Err(MemoryTrackerError::SharedMemorySetFailure);
+        }
+
+        SHARED_POOL
+            .set(Box::new(LockedFrameAllocator::new()))
+            .map_err(|_| MemoryTrackerError::SharedPoolSetFailure)?;
+
+        Ok(())
+    }
+
+    /// Initialize the shared heap from a static region of memory.
+    ///
+    /// Some hypervisors such as Gunyah do not support a MemShare API for guest
+    /// to share its memory with host. Instead they allow host to designate part
+    /// of guest memory as "shared" ahead of guest starting its execution. The
+    /// shared memory region is indicated in swiotlb node. On such platforms use
+    /// a separate heap to allocate buffers that can be shared with host.
+    pub fn init_static_shared_pool(&mut self, range: Range<usize>) -> Result<()> {
+        let size = NonZeroUsize::new(range.len()).unwrap();
+        let range = self.alloc_mut(range.start, size)?;
+        let shared_pool = LockedFrameAllocator::<32>::new();
+
+        shared_pool.lock().insert(range);
+
+        SHARED_POOL
+            .set(Box::new(shared_pool))
+            .map_err(|_| MemoryTrackerError::SharedPoolSetFailure)?;
+
+        Ok(())
+    }
+
+    /// Unshares any memory that may have been shared.
+    pub fn unshare_all_memory(&mut self) {
+        drop(SHARED_MEMORY.lock().take());
+    }
+
+    /// Handles translation fault for blocks flagged for lazy MMIO mapping by enabling the page
+    /// table entry and MMIO guard mapping the block. Breaks apart a block entry if required.
+    pub fn handle_mmio_fault(&mut self, addr: usize) -> Result<()> {
+        let page_range = page_4kb_of(addr)..page_4kb_of(addr) + MMIO_GUARD_GRANULE_SIZE;
+        self.page_table
+            .modify_range(&page_range, &verify_lazy_mapped_block)
+            .map_err(|_| MemoryTrackerError::InvalidPte)?;
+        get_hypervisor().mmio_guard_map(page_range.start)?;
+        // Maps a single device page, breaking up block mappings if necessary.
+        self.page_table.map_device(&page_range).map_err(|_| MemoryTrackerError::FailedToMap)
+    }
+
+    /// Flush all memory regions marked as writable-dirty.
+    fn flush_dirty_pages(&mut self) -> Result<()> {
+        // Collect memory ranges for which dirty state is tracked.
+        let writable_regions =
+            self.regions.iter().filter(|r| r.mem_type == MemoryType::ReadWrite).map(|r| &r.range);
+        // Execute a barrier instruction to ensure all hardware updates to the page table have been
+        // observed before reading PTE flags to determine dirty state.
+        dsb!("ish");
+        // Now flush writable-dirty pages in those regions.
+        for range in writable_regions.chain(once(&self.payload_range)) {
+            self.page_table
+                .modify_range(range, &flush_dirty_range)
+                .map_err(|_| MemoryTrackerError::FlushRegionFailed)?;
+        }
+        Ok(())
+    }
+
+    /// Handles permission fault for read-only blocks by setting writable-dirty state.
+    /// In general, this should be called from the exception handler when hardware dirty
+    /// state management is disabled or unavailable.
+    pub fn handle_permission_fault(&mut self, addr: usize) -> Result<()> {
+        self.page_table
+            .modify_range(&(addr..addr + 1), &mark_dirty_block)
+            .map_err(|_| MemoryTrackerError::SetPteDirtyFailed)
+    }
+}
+
+impl Drop for MemoryTracker {
+    fn drop(&mut self) {
+        set_dbm_enabled(false);
+        self.flush_dirty_pages().unwrap();
+        self.unshare_all_memory();
+    }
+}
+
+/// Allocates a memory range of at least the given size and alignment that is shared with the host.
+/// Returns a pointer to the buffer.
+pub fn alloc_shared(layout: Layout) -> hyp::Result<NonNull<u8>> {
+    assert_ne!(layout.size(), 0);
+    let Some(buffer) = try_shared_alloc(layout) else {
+        handle_alloc_error(layout);
+    };
+
+    trace!("Allocated shared buffer at {buffer:?} with {layout:?}");
+    Ok(buffer)
+}
+
+fn try_shared_alloc(layout: Layout) -> Option<NonNull<u8>> {
+    let mut shared_pool = SHARED_POOL.get().unwrap().lock();
+
+    if let Some(buffer) = shared_pool.alloc_aligned(layout) {
+        Some(NonNull::new(buffer as _).unwrap())
+    } else if let Some(shared_memory) = SHARED_MEMORY.lock().as_mut() {
+        shared_memory.refill(&mut shared_pool, layout);
+        shared_pool.alloc_aligned(layout).map(|buffer| NonNull::new(buffer as _).unwrap())
+    } else {
+        None
+    }
+}
+
+/// Unshares and deallocates a memory range which was previously allocated by `alloc_shared`.
+///
+/// The layout passed in must be the same layout passed to the original `alloc_shared` call.
+///
+/// # Safety
+///
+/// The memory must have been allocated by `alloc_shared` with the same layout, and not yet
+/// deallocated.
+pub unsafe fn dealloc_shared(vaddr: NonNull<u8>, layout: Layout) -> hyp::Result<()> {
+    SHARED_POOL.get().unwrap().lock().dealloc_aligned(vaddr.as_ptr() as usize, layout);
+
+    trace!("Deallocated shared buffer at {vaddr:?} with {layout:?}");
+    Ok(())
+}
 
 /// Allocates memory on the heap and shares it with the host.
 ///
 /// Unshares all pages when dropped.
-pub struct MemorySharer {
+struct MemorySharer {
     granule: usize,
     shared_regions: Vec<(usize, Layout)>,
 }
@@ -37,13 +361,13 @@
 impl MemorySharer {
     /// Constructs a new `MemorySharer` instance with the specified granule size and capacity.
     /// `granule` must be a power of 2.
-    pub fn new(granule: usize, capacity: usize) -> Self {
+    fn new(granule: usize, capacity: usize) -> Self {
         assert!(granule.is_power_of_two());
         Self { granule, shared_regions: Vec::with_capacity(capacity) }
     }
 
-    /// Get from the global allocator a granule-aligned region that suits `hint` and share it.
-    pub fn refill(&mut self, pool: &mut FrameAllocator<32>, hint: Layout) {
+    /// Gets from the global allocator a granule-aligned region that suits `hint` and share it.
+    fn refill(&mut self, pool: &mut FrameAllocator<32>, hint: Layout) {
         let layout = hint.align_to(self.granule).unwrap().pad_to_align();
         assert_ne!(layout.size(), 0);
         // SAFETY - layout has non-zero size.
@@ -81,10 +405,7 @@
 }
 
 /// Checks whether block flags indicate it should be MMIO guard mapped.
-/// As the return type is required by the crate `aarch64_paging`, we cannot address the lint
-/// issue `clippy::result_unit_err`.
-#[allow(clippy::result_unit_err)]
-pub fn verify_lazy_mapped_block(
+fn verify_lazy_mapped_block(
     _range: &VaRange,
     desc: &mut Descriptor,
     level: usize,
@@ -101,10 +422,7 @@
 }
 
 /// MMIO guard unmaps page
-/// As the return type is required by the crate `aarch64_paging`, we cannot address the lint
-/// issue `clippy::result_unit_err`.
-#[allow(clippy::result_unit_err)]
-pub fn mmio_guard_unmap_page(
+fn mmio_guard_unmap_page(
     va_range: &VaRange,
     desc: &mut Descriptor,
     level: usize,