diff --git a/pvmfw/avb/src/descriptor/collection.rs b/pvmfw/avb/src/descriptor/collection.rs
index f47bfbd..6784758 100644
--- a/pvmfw/avb/src/descriptor/collection.rs
+++ b/pvmfw/avb/src/descriptor/collection.rs
@@ -18,11 +18,11 @@
 use super::hash::HashDescriptor;
 use super::property::PropertyDescriptor;
 use crate::partition::PartitionName;
-use crate::utils::{self, is_not_null, to_usize, usize_checked_add};
+use crate::utils::{to_usize, usize_checked_add};
 use crate::PvmfwVerifyError;
+use avb::{IoError, IoResult, SlotVerifyError, SlotVerifyNoDataResult, VbmetaData};
 use avb_bindgen::{
     avb_descriptor_foreach, avb_descriptor_validate_and_byteswap, AvbDescriptor, AvbDescriptorTag,
-    AvbVBMetaData,
 };
 use core::{ffi::c_void, mem::size_of, slice};
 use tinyvec::ArrayVec;
@@ -36,24 +36,16 @@
 }
 
 impl<'a> Descriptors<'a> {
-    /// Builds `Descriptors` from `AvbVBMetaData`.
-    /// Returns an error if the given `AvbVBMetaData` contains non-hash descriptor, hash
+    /// Builds `Descriptors` from `VbmetaData`.
+    /// Returns an error if the given `VbmetaData` contains non-hash descriptor, hash
     /// descriptor of unknown `PartitionName` or duplicated hash descriptors.
-    ///
-    /// # Safety
-    ///
-    /// Behavior is undefined if any of the following conditions are violated:
-    /// * `vbmeta.vbmeta_data` must be non-null and points to a valid VBMeta.
-    /// * `vbmeta.vbmeta_data` must be valid for reading `vbmeta.vbmeta_size` bytes.
-    pub(crate) unsafe fn from_vbmeta(vbmeta: AvbVBMetaData) -> Result<Self, PvmfwVerifyError> {
-        is_not_null(vbmeta.vbmeta_data).map_err(|_| avb::SlotVerifyError::Io)?;
-        let mut res: Result<Self, avb::IoError> = Ok(Self::default());
-        // SAFETY: It is safe as the raw pointer `vbmeta.vbmeta_data` is a non-null pointer and
-        // points to a valid VBMeta structure.
+    pub(crate) fn from_vbmeta(vbmeta: &'a VbmetaData) -> Result<Self, PvmfwVerifyError> {
+        let mut res: IoResult<Self> = Ok(Self::default());
+        // SAFETY: It is safe as `vbmeta.data()` contains a valid VBMeta structure.
         let output = unsafe {
             avb_descriptor_foreach(
-                vbmeta.vbmeta_data,
-                vbmeta.vbmeta_size,
+                vbmeta.data().as_ptr(),
+                vbmeta.data().len(),
                 Some(check_and_save_descriptor),
                 &mut res as *mut _ as *mut c_void,
             )
@@ -61,7 +53,7 @@
         if output == res.is_ok() {
             res.map_err(PvmfwVerifyError::InvalidDescriptors)
         } else {
-            Err(avb::SlotVerifyError::InvalidMetadata.into())
+            Err(SlotVerifyError::InvalidMetadata.into())
         }
     }
 
@@ -74,11 +66,11 @@
     pub(crate) fn find_hash_descriptor(
         &self,
         partition_name: PartitionName,
-    ) -> Result<&HashDescriptor, avb::SlotVerifyError> {
+    ) -> SlotVerifyNoDataResult<&HashDescriptor> {
         self.hash_descriptors
             .iter()
             .find(|d| d.partition_name == partition_name)
-            .ok_or(avb::SlotVerifyError::InvalidMetadata)
+            .ok_or(SlotVerifyError::InvalidMetadata)
     }
 
     pub(crate) fn has_property_descriptor(&self) -> bool {
@@ -89,27 +81,24 @@
         self.prop_descriptor.as_ref().filter(|desc| desc.key == key).map(|desc| desc.value)
     }
 
-    fn push(&mut self, descriptor: Descriptor<'a>) -> utils::Result<()> {
+    fn push(&mut self, descriptor: Descriptor<'a>) -> IoResult<()> {
         match descriptor {
             Descriptor::Hash(d) => self.push_hash_descriptor(d),
             Descriptor::Property(d) => self.push_property_descriptor(d),
         }
     }
 
-    fn push_hash_descriptor(&mut self, descriptor: HashDescriptor<'a>) -> utils::Result<()> {
+    fn push_hash_descriptor(&mut self, descriptor: HashDescriptor<'a>) -> IoResult<()> {
         if self.hash_descriptors.iter().any(|d| d.partition_name == descriptor.partition_name) {
-            return Err(avb::IoError::Io);
+            return Err(IoError::Io);
         }
         self.hash_descriptors.push(descriptor);
         Ok(())
     }
 
-    fn push_property_descriptor(
-        &mut self,
-        descriptor: PropertyDescriptor<'a>,
-    ) -> utils::Result<()> {
+    fn push_property_descriptor(&mut self, descriptor: PropertyDescriptor<'a>) -> IoResult<()> {
         if self.prop_descriptor.is_some() {
-            return Err(avb::IoError::Io);
+            return Err(IoError::Io);
         }
         self.prop_descriptor.replace(descriptor);
         Ok(())
@@ -120,8 +109,7 @@
 ///
 /// Behavior is undefined if any of the following conditions are violated:
 /// * The `descriptor` pointer must be non-null and points to a valid `AvbDescriptor` struct.
-/// * The `user_data` pointer must be non-null, points to a valid
-///   `Result<Descriptors, avb::IoError>`
+/// * The `user_data` pointer must be non-null, points to a valid `IoResult<Descriptors>`
 ///  struct and is initialized.
 unsafe extern "C" fn check_and_save_descriptor(
     descriptor: *const AvbDescriptor,
@@ -129,8 +117,7 @@
 ) -> bool {
     // SAFETY: It is safe because the caller ensures that `user_data` points to a valid struct and
     // is initialized.
-    let Some(res) = (unsafe { (user_data as *mut Result<Descriptors, avb::IoError>).as_mut() })
-    else {
+    let Some(res) = (unsafe { (user_data as *mut IoResult<Descriptors>).as_mut() }) else {
         return false;
     };
     let Ok(descriptors) = res else {
@@ -154,7 +141,7 @@
 unsafe fn try_check_and_save_descriptor(
     descriptor: *const AvbDescriptor,
     descriptors: &mut Descriptors,
-) -> utils::Result<()> {
+) -> IoResult<()> {
     // SAFETY: It is safe because the caller ensures that `descriptor` is a non-null pointer
     // pointing to a valid struct.
     let descriptor = unsafe { Descriptor::from_descriptor_ptr(descriptor)? };
@@ -171,7 +158,7 @@
     ///
     /// Behavior is undefined if any of the following conditions are violated:
     /// * The `descriptor` pointer must be non-null and point to a valid `AvbDescriptor`.
-    unsafe fn from_descriptor_ptr(descriptor: *const AvbDescriptor) -> utils::Result<Self> {
+    unsafe fn from_descriptor_ptr(descriptor: *const AvbDescriptor) -> IoResult<Self> {
         let avb_descriptor =
         // SAFETY: It is safe as the raw pointer `descriptor` is non-null and points to
         // a valid `AvbDescriptor`.
@@ -197,7 +184,7 @@
                     unsafe { PropertyDescriptor::from_descriptor_ptr(descriptor, data)? };
                 Ok(Self::Property(descriptor))
             }
-            _ => Err(avb::IoError::NoSuchValue),
+            _ => Err(IoError::NoSuchValue),
         }
     }
 }
diff --git a/pvmfw/avb/src/descriptor/common.rs b/pvmfw/avb/src/descriptor/common.rs
index 31ee0a5..6063a7c 100644
--- a/pvmfw/avb/src/descriptor/common.rs
+++ b/pvmfw/avb/src/descriptor/common.rs
@@ -14,7 +14,8 @@
 
 //! Structs and functions used by all the descriptors.
 
-use crate::utils::{self, is_not_null};
+use crate::utils::is_not_null;
+use avb::{IoError, IoResult};
 use core::mem::MaybeUninit;
 
 /// # Safety
@@ -24,14 +25,14 @@
 pub(super) unsafe fn get_valid_descriptor<T>(
     descriptor_ptr: *const T,
     descriptor_validate_and_byteswap: unsafe extern "C" fn(src: *const T, dest: *mut T) -> bool,
-) -> utils::Result<T> {
+) -> IoResult<T> {
     is_not_null(descriptor_ptr)?;
     // SAFETY: It is safe because the caller ensures that `descriptor_ptr` is a non-null pointer
     // pointing to a valid struct.
     let descriptor = unsafe {
         let mut desc = MaybeUninit::uninit();
         if !descriptor_validate_and_byteswap(descriptor_ptr, desc.as_mut_ptr()) {
-            return Err(avb::IoError::Io);
+            return Err(IoError::Io);
         }
         desc.assume_init()
     };
diff --git a/pvmfw/avb/src/descriptor/hash.rs b/pvmfw/avb/src/descriptor/hash.rs
index 089268f..35db66d 100644
--- a/pvmfw/avb/src/descriptor/hash.rs
+++ b/pvmfw/avb/src/descriptor/hash.rs
@@ -16,7 +16,8 @@
 
 use super::common::get_valid_descriptor;
 use crate::partition::PartitionName;
-use crate::utils::{self, to_usize, usize_checked_add};
+use crate::utils::{to_usize, usize_checked_add};
+use avb::{IoError, IoResult};
 use avb_bindgen::{
     avb_hash_descriptor_validate_and_byteswap, AvbDescriptor, AvbHashDescriptor,
     AVB_SHA256_DIGEST_SIZE,
@@ -47,19 +48,19 @@
     pub(super) unsafe fn from_descriptor_ptr(
         descriptor: *const AvbDescriptor,
         data: &'a [u8],
-    ) -> utils::Result<Self> {
+    ) -> IoResult<Self> {
         // SAFETY: It is safe as the raw pointer `descriptor` is non-null and points to
         // a valid `AvbDescriptor`.
         let h = unsafe { HashDescriptorHeader::from_descriptor_ptr(descriptor)? };
         let partition_name = data
             .get(h.partition_name_range()?)
-            .ok_or(avb::IoError::RangeOutsidePartition)?
+            .ok_or(IoError::RangeOutsidePartition)?
             .try_into()?;
         let digest = data
             .get(h.digest_range()?)
-            .ok_or(avb::IoError::RangeOutsidePartition)?
+            .ok_or(IoError::RangeOutsidePartition)?
             .try_into()
-            .map_err(|_| avb::IoError::InvalidValueSize)?;
+            .map_err(|_| IoError::InvalidValueSize)?;
         Ok(Self { partition_name, digest })
     }
 }
@@ -71,7 +72,7 @@
     ///
     /// Behavior is undefined if any of the following conditions are violated:
     /// * The `descriptor` pointer must be non-null and point to a valid `AvbDescriptor`.
-    unsafe fn from_descriptor_ptr(descriptor: *const AvbDescriptor) -> utils::Result<Self> {
+    unsafe fn from_descriptor_ptr(descriptor: *const AvbDescriptor) -> IoResult<Self> {
         // SAFETY: It is safe as the raw pointer `descriptor` is non-null and points to
         // a valid `AvbDescriptor`.
         unsafe {
@@ -83,16 +84,16 @@
         }
     }
 
-    fn partition_name_end(&self) -> utils::Result<usize> {
+    fn partition_name_end(&self) -> IoResult<usize> {
         usize_checked_add(size_of::<AvbHashDescriptor>(), to_usize(self.0.partition_name_len)?)
     }
 
-    fn partition_name_range(&self) -> utils::Result<Range<usize>> {
+    fn partition_name_range(&self) -> IoResult<Range<usize>> {
         let start = size_of::<AvbHashDescriptor>();
         Ok(start..(self.partition_name_end()?))
     }
 
-    fn digest_range(&self) -> utils::Result<Range<usize>> {
+    fn digest_range(&self) -> IoResult<Range<usize>> {
         let start = usize_checked_add(self.partition_name_end()?, to_usize(self.0.salt_len)?)?;
         let end = usize_checked_add(start, to_usize(self.0.digest_len)?)?;
         Ok(start..end)
diff --git a/pvmfw/avb/src/descriptor/property.rs b/pvmfw/avb/src/descriptor/property.rs
index 336623a..8145d64 100644
--- a/pvmfw/avb/src/descriptor/property.rs
+++ b/pvmfw/avb/src/descriptor/property.rs
@@ -15,7 +15,8 @@
 //! Structs and functions relating to the property descriptor.
 
 use super::common::get_valid_descriptor;
-use crate::utils::{self, to_usize, usize_checked_add};
+use crate::utils::{to_usize, usize_checked_add};
+use avb::{IoError, IoResult};
 use avb_bindgen::{
     avb_property_descriptor_validate_and_byteswap, AvbDescriptor, AvbPropertyDescriptor,
 };
@@ -34,7 +35,7 @@
     pub(super) unsafe fn from_descriptor_ptr(
         descriptor: *const AvbDescriptor,
         data: &'a [u8],
-    ) -> utils::Result<Self> {
+    ) -> IoResult<Self> {
         // SAFETY: It is safe as the raw pointer `descriptor` is non-null and points to
         // a valid `AvbDescriptor`.
         let h = unsafe { PropertyDescriptorHeader::from_descriptor_ptr(descriptor)? };
@@ -43,12 +44,12 @@
         Ok(Self { key, value })
     }
 
-    fn get_valid_slice(data: &[u8], start: usize, end: usize) -> utils::Result<&[u8]> {
+    fn get_valid_slice(data: &[u8], start: usize, end: usize) -> IoResult<&[u8]> {
         const NUL_BYTE: u8 = b'\0';
 
         match data.get(end) {
-            Some(&NUL_BYTE) => data.get(start..end).ok_or(avb::IoError::RangeOutsidePartition),
-            _ => Err(avb::IoError::NoSuchValue),
+            Some(&NUL_BYTE) => data.get(start..end).ok_or(IoError::RangeOutsidePartition),
+            _ => Err(IoError::NoSuchValue),
         }
     }
 }
@@ -60,7 +61,7 @@
     ///
     /// Behavior is undefined if any of the following conditions are violated:
     /// * The `descriptor` pointer must be non-null and point to a valid `AvbDescriptor`.
-    unsafe fn from_descriptor_ptr(descriptor: *const AvbDescriptor) -> utils::Result<Self> {
+    unsafe fn from_descriptor_ptr(descriptor: *const AvbDescriptor) -> IoResult<Self> {
         // SAFETY: It is safe as the raw pointer `descriptor` is non-null and points to
         // a valid `AvbDescriptor`.
         unsafe {
@@ -76,16 +77,16 @@
         size_of::<AvbPropertyDescriptor>()
     }
 
-    fn key_end(&self) -> utils::Result<usize> {
+    fn key_end(&self) -> IoResult<usize> {
         usize_checked_add(self.key_start(), to_usize(self.0.key_num_bytes)?)
     }
 
-    fn value_start(&self) -> utils::Result<usize> {
+    fn value_start(&self) -> IoResult<usize> {
         // There is a NUL byte between key and value.
         usize_checked_add(self.key_end()?, 1)
     }
 
-    fn value_end(&self) -> utils::Result<usize> {
+    fn value_end(&self) -> IoResult<usize> {
         usize_checked_add(self.value_start()?, to_usize(self.0.value_num_bytes)?)
     }
 }
diff --git a/pvmfw/avb/src/error.rs b/pvmfw/avb/src/error.rs
index 0f052e8..4e3f27e 100644
--- a/pvmfw/avb/src/error.rs
+++ b/pvmfw/avb/src/error.rs
@@ -15,22 +15,23 @@
 //! This module contains the error thrown by the payload verification API
 //! and other errors used in the library.
 
+use avb::{IoError, SlotVerifyError};
 use core::fmt;
 
-/// Wrapper around `avb::SlotVerifyError` to add custom pvmfw errors.
+/// Wrapper around `SlotVerifyError` to add custom pvmfw errors.
 /// It is the error thrown by the payload verification API `verify_payload()`.
 #[derive(Debug, PartialEq, Eq)]
 pub enum PvmfwVerifyError {
-    /// Passthrough `avb::SlotVerifyError` with no `SlotVerifyData`.
-    AvbError(avb::SlotVerifyError<'static>),
+    /// Passthrough `SlotVerifyError` with no `SlotVerifyData`.
+    AvbError(SlotVerifyError<'static>),
     /// VBMeta has invalid descriptors.
-    InvalidDescriptors(avb::IoError),
+    InvalidDescriptors(IoError),
     /// Unknown vbmeta property.
     UnknownVbmetaProperty,
 }
 
-impl From<avb::SlotVerifyError<'_>> for PvmfwVerifyError {
-    fn from(error: avb::SlotVerifyError) -> Self {
+impl From<SlotVerifyError<'_>> for PvmfwVerifyError {
+    fn from(error: SlotVerifyError) -> Self {
         // We don't use verification data on failure, drop it to get a `'static` lifetime.
         Self::AvbError(error.without_verify_data())
     }
diff --git a/pvmfw/avb/src/ops.rs b/pvmfw/avb/src/ops.rs
index aee93c8..9711f72 100644
--- a/pvmfw/avb/src/ops.rs
+++ b/pvmfw/avb/src/ops.rs
@@ -12,22 +12,14 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-//! Structs and functions relating to `AvbOps`.
+//! Structs and functions relating to AVB callback operations.
 
 use crate::partition::PartitionName;
-use crate::utils::{self, as_ref, is_not_null, to_nonnull, write};
-use avb::internal::{result_to_io_enum, slot_verify_enum_to_result};
-use avb_bindgen::{
-    avb_slot_verify, avb_slot_verify_data_free, AvbHashtreeErrorMode, AvbIOResult, AvbOps,
-    AvbPartitionData, AvbSlotVerifyData, AvbSlotVerifyFlags, AvbVBMetaData,
+use avb::{
+    slot_verify, HashtreeErrorMode, IoError, IoResult, PublicKeyForPartitionInfo, SlotVerifyData,
+    SlotVerifyFlags, SlotVerifyResult,
 };
-use core::{
-    ffi::{c_char, c_void, CStr},
-    mem::MaybeUninit,
-    ptr, slice,
-};
-
-const NULL_BYTE: &[u8] = b"\0";
+use core::ffi::CStr;
 
 pub(crate) struct Payload<'a> {
     kernel: &'a [u8],
@@ -35,15 +27,6 @@
     trusted_public_key: &'a [u8],
 }
 
-impl<'a> AsRef<Payload<'a>> for AvbOps {
-    fn as_ref(&self) -> &Payload<'a> {
-        let payload = self.user_data as *const Payload;
-        // SAFETY: It is safe to cast the `AvbOps.user_data` to Payload as we have saved a
-        // pointer to a valid value of Payload in user_data when creating AvbOps.
-        unsafe { &*payload }
-    }
-}
-
 impl<'a> Payload<'a> {
     pub(crate) fn new(
         kernel: &'a [u8],
@@ -53,148 +36,116 @@
         Self { kernel, initrd, trusted_public_key }
     }
 
-    fn get_partition(&self, partition_name: *const c_char) -> Result<&[u8], avb::IoError> {
+    fn get_partition(&self, partition_name: &CStr) -> IoResult<&[u8]> {
         match partition_name.try_into()? {
             PartitionName::Kernel => Ok(self.kernel),
             PartitionName::InitrdNormal | PartitionName::InitrdDebug => {
-                self.initrd.ok_or(avb::IoError::NoSuchPartition)
+                self.initrd.ok_or(IoError::NoSuchPartition)
             }
         }
     }
 }
 
-/// `Ops` wraps the class `AvbOps` in libavb. It provides pvmfw customized
-/// operations used in the verification.
-pub(crate) struct Ops(AvbOps);
-
-impl<'a> From<&mut Payload<'a>> for Ops {
-    fn from(payload: &mut Payload<'a>) -> Self {
-        let avb_ops = AvbOps {
-            user_data: payload as *mut _ as *mut c_void,
-            ab_ops: ptr::null_mut(),
-            atx_ops: ptr::null_mut(),
-            read_from_partition: Some(read_from_partition),
-            get_preloaded_partition: Some(get_preloaded_partition),
-            write_to_partition: None,
-            validate_vbmeta_public_key: Some(validate_vbmeta_public_key),
-            read_rollback_index: Some(read_rollback_index),
-            write_rollback_index: None,
-            read_is_device_unlocked: Some(read_is_device_unlocked),
-            get_unique_guid_for_partition: Some(get_unique_guid_for_partition),
-            get_size_of_partition: Some(get_size_of_partition),
-            read_persistent_value: None,
-            write_persistent_value: None,
-            validate_public_key_for_partition: None,
-        };
-        Self(avb_ops)
-    }
+/// Pvmfw customized operations used in the verification.
+pub(crate) struct Ops<'a> {
+    payload: &'a Payload<'a>,
 }
 
-impl Ops {
+impl<'a> Ops<'a> {
+    pub(crate) fn new(payload: &'a Payload<'a>) -> Self {
+        Self { payload }
+    }
+
     pub(crate) fn verify_partition(
         &mut self,
         partition_name: &CStr,
-    ) -> Result<AvbSlotVerifyDataWrap, avb::SlotVerifyError<'static>> {
-        let requested_partitions = [partition_name.as_ptr(), ptr::null()];
-        let ab_suffix = CStr::from_bytes_with_nul(NULL_BYTE).unwrap();
-        let mut out_data = MaybeUninit::uninit();
-        // SAFETY: It is safe to call `avb_slot_verify()` as the pointer arguments (`ops`,
-        // `requested_partitions` and `ab_suffix`) passed to the method are all valid and
-        // initialized.
-        let result = unsafe {
-            avb_slot_verify(
-                &mut self.0,
-                requested_partitions.as_ptr(),
-                ab_suffix.as_ptr(),
-                AvbSlotVerifyFlags::AVB_SLOT_VERIFY_FLAGS_NONE,
-                AvbHashtreeErrorMode::AVB_HASHTREE_ERROR_MODE_RESTART_AND_INVALIDATE,
-                out_data.as_mut_ptr(),
-            )
-        };
-        slot_verify_enum_to_result(result)?;
-        // SAFETY: This is safe because `out_data` has been properly initialized after
-        // calling `avb_slot_verify` and it returns OK.
-        let out_data = unsafe { out_data.assume_init() };
-        out_data.try_into()
+    ) -> SlotVerifyResult<SlotVerifyData> {
+        slot_verify(
+            self,
+            &[partition_name],
+            None, // No partition slot suffix.
+            SlotVerifyFlags::AVB_SLOT_VERIFY_FLAGS_NONE,
+            HashtreeErrorMode::AVB_HASHTREE_ERROR_MODE_RESTART_AND_INVALIDATE,
+        )
     }
 }
 
-extern "C" fn read_is_device_unlocked(
-    _ops: *mut AvbOps,
-    out_is_unlocked: *mut bool,
-) -> AvbIOResult {
-    result_to_io_enum(write(out_is_unlocked, false))
+impl<'a> avb::Ops for Ops<'a> {
+    fn read_from_partition(
+        &mut self,
+        partition: &CStr,
+        offset: i64,
+        buffer: &mut [u8],
+    ) -> IoResult<usize> {
+        let partition = self.payload.get_partition(partition)?;
+        copy_data_to_dst(partition, offset, buffer)?;
+        Ok(buffer.len())
+    }
+
+    fn get_preloaded_partition(&mut self, partition: &CStr) -> IoResult<&[u8]> {
+        self.payload.get_partition(partition)
+    }
+
+    fn validate_vbmeta_public_key(
+        &mut self,
+        public_key: &[u8],
+        _public_key_metadata: Option<&[u8]>,
+    ) -> IoResult<bool> {
+        // The public key metadata is not used when we build the VBMeta.
+        Ok(self.payload.trusted_public_key == public_key)
+    }
+
+    fn read_rollback_index(&mut self, _rollback_index_location: usize) -> IoResult<u64> {
+        // TODO(291213394) : Refine this comment once capability for rollback protection is defined.
+        // pvmfw does not compare stored_rollback_index with rollback_index for Antirollback
+        // protection. Hence, we set `out_rollback_index` to 0 to ensure that the rollback_index
+        // (including default: 0) is never smaller than it, thus the rollback index check will pass.
+        Ok(0)
+    }
+
+    fn write_rollback_index(
+        &mut self,
+        _rollback_index_location: usize,
+        _index: u64,
+    ) -> IoResult<()> {
+        Err(IoError::NotImplemented)
+    }
+
+    fn read_is_device_unlocked(&mut self) -> IoResult<bool> {
+        Ok(false)
+    }
+
+    fn get_size_of_partition(&mut self, partition: &CStr) -> IoResult<u64> {
+        let partition = self.payload.get_partition(partition)?;
+        u64::try_from(partition.len()).map_err(|_| IoError::InvalidValueSize)
+    }
+
+    fn read_persistent_value(&mut self, _name: &CStr, _value: &mut [u8]) -> IoResult<usize> {
+        Err(IoError::NotImplemented)
+    }
+
+    fn write_persistent_value(&mut self, _name: &CStr, _value: &[u8]) -> IoResult<()> {
+        Err(IoError::NotImplemented)
+    }
+
+    fn erase_persistent_value(&mut self, _name: &CStr) -> IoResult<()> {
+        Err(IoError::NotImplemented)
+    }
+
+    fn validate_public_key_for_partition(
+        &mut self,
+        _partition: &CStr,
+        _public_key: &[u8],
+        _public_key_metadata: Option<&[u8]>,
+    ) -> IoResult<PublicKeyForPartitionInfo> {
+        Err(IoError::NotImplemented)
+    }
 }
 
-extern "C" fn get_preloaded_partition(
-    ops: *mut AvbOps,
-    partition: *const c_char,
-    num_bytes: usize,
-    out_pointer: *mut *mut u8,
-    out_num_bytes_preloaded: *mut usize,
-) -> AvbIOResult {
-    result_to_io_enum(try_get_preloaded_partition(
-        ops,
-        partition,
-        num_bytes,
-        out_pointer,
-        out_num_bytes_preloaded,
-    ))
-}
-
-fn try_get_preloaded_partition(
-    ops: *mut AvbOps,
-    partition: *const c_char,
-    num_bytes: usize,
-    out_pointer: *mut *mut u8,
-    out_num_bytes_preloaded: *mut usize,
-) -> utils::Result<()> {
-    let ops = as_ref(ops)?;
-    let partition = ops.as_ref().get_partition(partition)?;
-    write(out_pointer, partition.as_ptr() as *mut u8)?;
-    write(out_num_bytes_preloaded, partition.len().min(num_bytes))
-}
-
-extern "C" fn read_from_partition(
-    ops: *mut AvbOps,
-    partition: *const c_char,
-    offset: i64,
-    num_bytes: usize,
-    buffer: *mut c_void,
-    out_num_read: *mut usize,
-) -> AvbIOResult {
-    result_to_io_enum(try_read_from_partition(
-        ops,
-        partition,
-        offset,
-        num_bytes,
-        buffer,
-        out_num_read,
-    ))
-}
-
-fn try_read_from_partition(
-    ops: *mut AvbOps,
-    partition: *const c_char,
-    offset: i64,
-    num_bytes: usize,
-    buffer: *mut c_void,
-    out_num_read: *mut usize,
-) -> utils::Result<()> {
-    let ops = as_ref(ops)?;
-    let partition = ops.as_ref().get_partition(partition)?;
-    let buffer = to_nonnull(buffer)?;
-    // SAFETY: It is safe to copy the requested number of bytes to `buffer` as `buffer`
-    // is created to point to the `num_bytes` of bytes in memory.
-    let buffer_slice = unsafe { slice::from_raw_parts_mut(buffer.as_ptr() as *mut u8, num_bytes) };
-    copy_data_to_dst(partition, offset, buffer_slice)?;
-    write(out_num_read, buffer_slice.len())
-}
-
-fn copy_data_to_dst(src: &[u8], offset: i64, dst: &mut [u8]) -> utils::Result<()> {
-    let start = to_copy_start(offset, src.len()).ok_or(avb::IoError::InvalidValueSize)?;
-    let end = start.checked_add(dst.len()).ok_or(avb::IoError::InvalidValueSize)?;
-    dst.copy_from_slice(src.get(start..end).ok_or(avb::IoError::RangeOutsidePartition)?);
+fn copy_data_to_dst(src: &[u8], offset: i64, dst: &mut [u8]) -> IoResult<()> {
+    let start = to_copy_start(offset, src.len()).ok_or(IoError::InvalidValueSize)?;
+    let end = start.checked_add(dst.len()).ok_or(IoError::InvalidValueSize)?;
+    dst.copy_from_slice(src.get(start..end).ok_or(IoError::RangeOutsidePartition)?);
     Ok(())
 }
 
@@ -203,143 +154,3 @@
         .ok()
         .or_else(|| isize::try_from(offset).ok().and_then(|v| len.checked_add_signed(v)))
 }
-
-extern "C" fn get_size_of_partition(
-    ops: *mut AvbOps,
-    partition: *const c_char,
-    out_size_num_bytes: *mut u64,
-) -> AvbIOResult {
-    result_to_io_enum(try_get_size_of_partition(ops, partition, out_size_num_bytes))
-}
-
-fn try_get_size_of_partition(
-    ops: *mut AvbOps,
-    partition: *const c_char,
-    out_size_num_bytes: *mut u64,
-) -> utils::Result<()> {
-    let ops = as_ref(ops)?;
-    let partition = ops.as_ref().get_partition(partition)?;
-    let partition_size =
-        u64::try_from(partition.len()).map_err(|_| avb::IoError::InvalidValueSize)?;
-    write(out_size_num_bytes, partition_size)
-}
-
-extern "C" fn read_rollback_index(
-    _ops: *mut AvbOps,
-    _rollback_index_location: usize,
-    out_rollback_index: *mut u64,
-) -> AvbIOResult {
-    // This method is used by `avb_slot_verify()` to read the stored_rollback_index at
-    // rollback_index_location.
-
-    // TODO(291213394) : Refine this comment once capability for rollback protection is defined.
-    // pvmfw does not compare stored_rollback_index with rollback_index for Antirollback protection
-    // Hence, we set `out_rollback_index` to 0 to ensure that the
-    // rollback_index (including default: 0) is never smaller than it,
-    // thus the rollback index check will pass.
-    result_to_io_enum(write(out_rollback_index, 0))
-}
-
-extern "C" fn get_unique_guid_for_partition(
-    _ops: *mut AvbOps,
-    _partition: *const c_char,
-    _guid_buf: *mut c_char,
-    _guid_buf_size: usize,
-) -> AvbIOResult {
-    // TODO(b/256148034): Check if it's possible to throw an error here instead of having
-    // an empty method.
-    // This method is required by `avb_slot_verify()`.
-    AvbIOResult::AVB_IO_RESULT_OK
-}
-
-extern "C" fn validate_vbmeta_public_key(
-    ops: *mut AvbOps,
-    public_key_data: *const u8,
-    public_key_length: usize,
-    public_key_metadata: *const u8,
-    public_key_metadata_length: usize,
-    out_is_trusted: *mut bool,
-) -> AvbIOResult {
-    result_to_io_enum(try_validate_vbmeta_public_key(
-        ops,
-        public_key_data,
-        public_key_length,
-        public_key_metadata,
-        public_key_metadata_length,
-        out_is_trusted,
-    ))
-}
-
-fn try_validate_vbmeta_public_key(
-    ops: *mut AvbOps,
-    public_key_data: *const u8,
-    public_key_length: usize,
-    _public_key_metadata: *const u8,
-    _public_key_metadata_length: usize,
-    out_is_trusted: *mut bool,
-) -> utils::Result<()> {
-    // The public key metadata is not used when we build the VBMeta.
-    is_not_null(public_key_data)?;
-    // SAFETY: It is safe to create a slice with the given pointer and length as
-    // `public_key_data` is a valid pointer and it points to an array of length
-    // `public_key_length`.
-    let public_key = unsafe { slice::from_raw_parts(public_key_data, public_key_length) };
-    let ops = as_ref(ops)?;
-    let trusted_public_key = ops.as_ref().trusted_public_key;
-    write(out_is_trusted, public_key == trusted_public_key)
-}
-
-pub(crate) struct AvbSlotVerifyDataWrap(*mut AvbSlotVerifyData);
-
-impl TryFrom<*mut AvbSlotVerifyData> for AvbSlotVerifyDataWrap {
-    type Error = avb::SlotVerifyError<'static>;
-
-    fn try_from(data: *mut AvbSlotVerifyData) -> Result<Self, Self::Error> {
-        is_not_null(data).map_err(|_| avb::SlotVerifyError::Io)?;
-        Ok(Self(data))
-    }
-}
-
-impl Drop for AvbSlotVerifyDataWrap {
-    fn drop(&mut self) {
-        // SAFETY: This is safe because `self.0` is checked nonnull when the
-        // instance is created. We can free this pointer when the instance is
-        // no longer needed.
-        unsafe {
-            avb_slot_verify_data_free(self.0);
-        }
-    }
-}
-
-impl AsRef<AvbSlotVerifyData> for AvbSlotVerifyDataWrap {
-    fn as_ref(&self) -> &AvbSlotVerifyData {
-        // This is safe because `self.0` is checked nonnull when the instance is created.
-        as_ref(self.0).unwrap()
-    }
-}
-
-impl AvbSlotVerifyDataWrap {
-    pub(crate) fn vbmeta_images(&self) -> Result<&[AvbVBMetaData], avb::SlotVerifyError> {
-        let data = self.as_ref();
-        is_not_null(data.vbmeta_images).map_err(|_| avb::SlotVerifyError::Io)?;
-        let vbmeta_images =
-        // SAFETY: It is safe as the raw pointer `data.vbmeta_images` is a nonnull pointer.
-            unsafe { slice::from_raw_parts(data.vbmeta_images, data.num_vbmeta_images) };
-        Ok(vbmeta_images)
-    }
-
-    pub(crate) fn loaded_partitions(&self) -> Result<&[AvbPartitionData], avb::SlotVerifyError> {
-        let data = self.as_ref();
-        is_not_null(data.loaded_partitions).map_err(|_| avb::SlotVerifyError::Io)?;
-        let loaded_partitions =
-        // SAFETY: It is safe as the raw pointer `data.loaded_partitions` is a nonnull pointer and
-        // is guaranteed by libavb to point to a valid `AvbPartitionData` array as part of the
-        // `AvbSlotVerifyData` struct.
-            unsafe { slice::from_raw_parts(data.loaded_partitions, data.num_loaded_partitions) };
-        Ok(loaded_partitions)
-    }
-
-    pub(crate) fn rollback_indexes(&self) -> &[u64] {
-        &self.as_ref().rollback_indexes
-    }
-}
diff --git a/pvmfw/avb/src/partition.rs b/pvmfw/avb/src/partition.rs
index ca450c9..3fe9479 100644
--- a/pvmfw/avb/src/partition.rs
+++ b/pvmfw/avb/src/partition.rs
@@ -14,8 +14,8 @@
 
 //! Struct and functions relating to well-known partition names.
 
-use crate::utils::is_not_null;
-use core::ffi::{c_char, CStr};
+use avb::IoError;
+use core::ffi::CStr;
 
 #[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
 pub(crate) enum PartitionName {
@@ -51,39 +51,28 @@
     }
 }
 
-impl TryFrom<*const c_char> for PartitionName {
-    type Error = avb::IoError;
-
-    fn try_from(partition_name: *const c_char) -> Result<Self, Self::Error> {
-        is_not_null(partition_name)?;
-        // SAFETY: It is safe as the raw pointer `partition_name` is a nonnull pointer.
-        let partition_name = unsafe { CStr::from_ptr(partition_name) };
-        partition_name.try_into()
-    }
-}
-
 impl TryFrom<&CStr> for PartitionName {
-    type Error = avb::IoError;
+    type Error = IoError;
 
     fn try_from(partition_name: &CStr) -> Result<Self, Self::Error> {
         match partition_name.to_bytes_with_nul() {
             Self::KERNEL_PARTITION_NAME => Ok(Self::Kernel),
             Self::INITRD_NORMAL_PARTITION_NAME => Ok(Self::InitrdNormal),
             Self::INITRD_DEBUG_PARTITION_NAME => Ok(Self::InitrdDebug),
-            _ => Err(avb::IoError::NoSuchPartition),
+            _ => Err(IoError::NoSuchPartition),
         }
     }
 }
 
 impl TryFrom<&[u8]> for PartitionName {
-    type Error = avb::IoError;
+    type Error = IoError;
 
     fn try_from(non_null_terminated_name: &[u8]) -> Result<Self, Self::Error> {
         match non_null_terminated_name {
             x if x == Self::Kernel.as_non_null_terminated_bytes() => Ok(Self::Kernel),
             x if x == Self::InitrdNormal.as_non_null_terminated_bytes() => Ok(Self::InitrdNormal),
             x if x == Self::InitrdDebug.as_non_null_terminated_bytes() => Ok(Self::InitrdDebug),
-            _ => Err(avb::IoError::NoSuchPartition),
+            _ => Err(IoError::NoSuchPartition),
         }
     }
 }
diff --git a/pvmfw/avb/src/utils.rs b/pvmfw/avb/src/utils.rs
index f4f15e1..b4f099b 100644
--- a/pvmfw/avb/src/utils.rs
+++ b/pvmfw/avb/src/utils.rs
@@ -14,42 +14,20 @@
 
 //! Common utility functions.
 
-use core::ptr::NonNull;
-use core::result;
+use avb::{IoError, IoResult};
 
-pub(crate) type Result<T> = result::Result<T, avb::IoError>;
-
-pub(crate) fn write<T>(ptr: *mut T, value: T) -> Result<()> {
-    let ptr = to_nonnull(ptr)?;
-    // SAFETY: It is safe as the raw pointer `ptr` is a non-null pointer.
-    unsafe {
-        *ptr.as_ptr() = value;
-    }
-    Ok(())
-}
-
-pub(crate) fn as_ref<'a, T>(ptr: *mut T) -> Result<&'a T> {
-    let ptr = to_nonnull(ptr)?;
-    // SAFETY: It is safe as the raw pointer `ptr` is a non-null pointer.
-    unsafe { Ok(ptr.as_ref()) }
-}
-
-pub(crate) fn to_nonnull<T>(ptr: *mut T) -> Result<NonNull<T>> {
-    NonNull::new(ptr).ok_or(avb::IoError::NoSuchValue)
-}
-
-pub(crate) fn is_not_null<T>(ptr: *const T) -> Result<()> {
+pub(crate) fn is_not_null<T>(ptr: *const T) -> IoResult<()> {
     if ptr.is_null() {
-        Err(avb::IoError::NoSuchValue)
+        Err(IoError::NoSuchValue)
     } else {
         Ok(())
     }
 }
 
-pub(crate) fn to_usize<T: TryInto<usize>>(num: T) -> Result<usize> {
-    num.try_into().map_err(|_| avb::IoError::InvalidValueSize)
+pub(crate) fn to_usize<T: TryInto<usize>>(num: T) -> IoResult<usize> {
+    num.try_into().map_err(|_| IoError::InvalidValueSize)
 }
 
-pub(crate) fn usize_checked_add(x: usize, y: usize) -> Result<usize> {
-    x.checked_add(y).ok_or(avb::IoError::InvalidValueSize)
+pub(crate) fn usize_checked_add(x: usize, y: usize) -> IoResult<usize> {
+    x.checked_add(y).ok_or(IoError::InvalidValueSize)
 }
diff --git a/pvmfw/avb/src/verify.rs b/pvmfw/avb/src/verify.rs
index 3274033..ac015e0 100644
--- a/pvmfw/avb/src/verify.rs
+++ b/pvmfw/avb/src/verify.rs
@@ -20,10 +20,9 @@
 use crate::PvmfwVerifyError;
 use alloc::vec;
 use alloc::vec::Vec;
-use avb_bindgen::{AvbPartitionData, AvbVBMetaData};
-use core::ffi::c_char;
+use avb::{PartitionData, SlotVerifyError, SlotVerifyNoDataResult, VbmetaData};
 
-// We use this for the rollback_index field if AvbSlotVerifyDataWrap has empty rollback_indexes
+// We use this for the rollback_index field if SlotVerifyData has empty rollback_indexes
 const DEFAULT_ROLLBACK_INDEX: u64 = 0;
 
 /// Verified data returned when the payload verification succeeds.
@@ -84,7 +83,7 @@
                 _ => return Err(PvmfwVerifyError::UnknownVbmetaProperty),
             };
             if res.contains(&cap) {
-                return Err(avb::SlotVerifyError::InvalidMetadata.into());
+                return Err(SlotVerifyError::InvalidMetadata.into());
             }
             res.push(cap);
         }
@@ -92,55 +91,51 @@
     }
 }
 
-fn verify_only_one_vbmeta_exists(
-    vbmeta_images: &[AvbVBMetaData],
-) -> Result<(), avb::SlotVerifyError<'static>> {
-    if vbmeta_images.len() == 1 {
+fn verify_only_one_vbmeta_exists(vbmeta_data: &[VbmetaData]) -> SlotVerifyNoDataResult<()> {
+    if vbmeta_data.len() == 1 {
         Ok(())
     } else {
-        Err(avb::SlotVerifyError::InvalidMetadata)
+        Err(SlotVerifyError::InvalidMetadata)
     }
 }
 
-fn verify_vbmeta_is_from_kernel_partition(
-    vbmeta_image: &AvbVBMetaData,
-) -> Result<(), avb::SlotVerifyError<'static>> {
-    match (vbmeta_image.partition_name as *const c_char).try_into() {
+fn verify_vbmeta_is_from_kernel_partition(vbmeta_image: &VbmetaData) -> SlotVerifyNoDataResult<()> {
+    match vbmeta_image.partition_name().try_into() {
         Ok(PartitionName::Kernel) => Ok(()),
-        _ => Err(avb::SlotVerifyError::InvalidMetadata),
+        _ => Err(SlotVerifyError::InvalidMetadata),
     }
 }
 
 fn verify_vbmeta_has_only_one_hash_descriptor(
     descriptors: &Descriptors,
-) -> Result<(), avb::SlotVerifyError<'static>> {
+) -> SlotVerifyNoDataResult<()> {
     if descriptors.num_hash_descriptor() == 1 {
         Ok(())
     } else {
-        Err(avb::SlotVerifyError::InvalidMetadata)
+        Err(SlotVerifyError::InvalidMetadata)
     }
 }
 
 fn verify_loaded_partition_has_expected_length(
-    loaded_partitions: &[AvbPartitionData],
+    loaded_partitions: &[PartitionData],
     partition_name: PartitionName,
     expected_len: usize,
-) -> Result<(), avb::SlotVerifyError<'static>> {
+) -> SlotVerifyNoDataResult<()> {
     if loaded_partitions.len() != 1 {
         // Only one partition should be loaded in each verify result.
-        return Err(avb::SlotVerifyError::Io);
+        return Err(SlotVerifyError::Io);
     }
-    let loaded_partition = loaded_partitions[0];
-    if !PartitionName::try_from(loaded_partition.partition_name as *const c_char)
+    let loaded_partition = &loaded_partitions[0];
+    if !PartitionName::try_from(loaded_partition.partition_name())
         .map_or(false, |p| p == partition_name)
     {
         // Only the requested partition should be loaded.
-        return Err(avb::SlotVerifyError::Io);
+        return Err(SlotVerifyError::Io);
     }
-    if loaded_partition.data_size == expected_len {
+    if loaded_partition.data().len() == expected_len {
         Ok(())
     } else {
-        Err(avb::SlotVerifyError::Verification(None))
+        Err(SlotVerifyError::Verification(None))
     }
 }
 
@@ -158,28 +153,40 @@
         .and_then(Capability::get_capabilities)
 }
 
+/// Verifies the given initrd partition, and checks that the resulting contents looks like expected.
+fn verify_initrd(
+    ops: &mut Ops,
+    partition_name: PartitionName,
+    expected_initrd: &[u8],
+) -> SlotVerifyNoDataResult<()> {
+    let result =
+        ops.verify_partition(partition_name.as_cstr()).map_err(|e| e.without_verify_data())?;
+    verify_loaded_partition_has_expected_length(
+        result.partition_data(),
+        partition_name,
+        expected_initrd.len(),
+    )
+}
+
 /// Verifies the payload (signed kernel + initrd) against the trusted public key.
 pub fn verify_payload<'a>(
     kernel: &[u8],
     initrd: Option<&[u8]>,
     trusted_public_key: &'a [u8],
 ) -> Result<VerifiedBootData<'a>, PvmfwVerifyError> {
-    let mut payload = Payload::new(kernel, initrd, trusted_public_key);
-    let mut ops = Ops::from(&mut payload);
+    let payload = Payload::new(kernel, initrd, trusted_public_key);
+    let mut ops = Ops::new(&payload);
     let kernel_verify_result = ops.verify_partition(PartitionName::Kernel.as_cstr())?;
 
-    let vbmeta_images = kernel_verify_result.vbmeta_images()?;
+    let vbmeta_images = kernel_verify_result.vbmeta_data();
     // TODO(b/302093437): Use explicit rollback_index_location instead of default
     // location (first element).
     let rollback_index =
         *kernel_verify_result.rollback_indexes().first().unwrap_or(&DEFAULT_ROLLBACK_INDEX);
     verify_only_one_vbmeta_exists(vbmeta_images)?;
-    let vbmeta_image = vbmeta_images[0];
-    verify_vbmeta_is_from_kernel_partition(&vbmeta_image)?;
-    // SAFETY: It is safe because the `vbmeta_image` is collected from `AvbSlotVerifyData`,
-    // which is returned by `avb_slot_verify()` when the verification succeeds. It is
-    // guaranteed by libavb to be non-null and to point to a valid VBMeta structure.
-    let descriptors = unsafe { Descriptors::from_vbmeta(vbmeta_image)? };
+    let vbmeta_image = &vbmeta_images[0];
+    verify_vbmeta_is_from_kernel_partition(vbmeta_image)?;
+    let descriptors = Descriptors::from_vbmeta(vbmeta_image)?;
     let capabilities = verify_property_and_get_capabilities(&descriptors)?;
     let kernel_descriptor = descriptors.find_hash_descriptor(PartitionName::Kernel)?;
 
@@ -196,20 +203,15 @@
     }
 
     let initrd = initrd.unwrap();
-    let (debug_level, initrd_verify_result, initrd_partition_name) =
-        if let Ok(result) = ops.verify_partition(PartitionName::InitrdNormal.as_cstr()) {
-            (DebugLevel::None, result, PartitionName::InitrdNormal)
-        } else if let Ok(result) = ops.verify_partition(PartitionName::InitrdDebug.as_cstr()) {
-            (DebugLevel::Full, result, PartitionName::InitrdDebug)
+    let mut initrd_ops = Ops::new(&payload);
+    let (debug_level, initrd_partition_name) =
+        if verify_initrd(&mut initrd_ops, PartitionName::InitrdNormal, initrd).is_ok() {
+            (DebugLevel::None, PartitionName::InitrdNormal)
+        } else if verify_initrd(&mut initrd_ops, PartitionName::InitrdDebug, initrd).is_ok() {
+            (DebugLevel::Full, PartitionName::InitrdDebug)
         } else {
-            return Err(avb::SlotVerifyError::Verification(None).into());
+            return Err(SlotVerifyError::Verification(None).into());
         };
-    let loaded_partitions = initrd_verify_result.loaded_partitions()?;
-    verify_loaded_partition_has_expected_length(
-        loaded_partitions,
-        initrd_partition_name,
-        initrd.len(),
-    )?;
     let initrd_descriptor = descriptors.find_hash_descriptor(initrd_partition_name)?;
     Ok(VerifiedBootData {
         debug_level,
diff --git a/pvmfw/avb/tests/api_test.rs b/pvmfw/avb/tests/api_test.rs
index 84f83c2..6dc5a0a 100644
--- a/pvmfw/avb/tests/api_test.rs
+++ b/pvmfw/avb/tests/api_test.rs
@@ -17,6 +17,7 @@
 mod utils;
 
 use anyhow::{anyhow, Result};
+use avb::{IoError, SlotVerifyError};
 use avb_bindgen::{AvbFooter, AvbVBMetaImageHeader};
 use pvmfw_avb::{verify_payload, Capability, DebugLevel, PvmfwVerifyError, VerifiedBootData};
 use std::{fs, mem::size_of, ptr};
@@ -87,7 +88,7 @@
         &fs::read(TEST_IMG_WITH_NON_INITRD_HASHDESC_PATH)?,
         /* initrd= */ None,
         &load_trusted_public_key()?,
-        PvmfwVerifyError::InvalidDescriptors(avb::IoError::NoSuchPartition),
+        PvmfwVerifyError::InvalidDescriptors(IoError::NoSuchPartition),
     )
 }
 
@@ -97,7 +98,7 @@
         &fs::read(TEST_IMG_WITH_INITRD_AND_NON_INITRD_DESC_PATH)?,
         &load_latest_initrd_normal()?,
         &load_trusted_public_key()?,
-        PvmfwVerifyError::InvalidDescriptors(avb::IoError::NoSuchPartition),
+        PvmfwVerifyError::InvalidDescriptors(IoError::NoSuchPartition),
     )
 }
 
@@ -141,7 +142,7 @@
         &fs::read(TEST_IMG_WITH_MULTIPLE_PROPS_PATH)?,
         /* initrd= */ None,
         &load_trusted_public_key()?,
-        PvmfwVerifyError::InvalidDescriptors(avb::IoError::Io),
+        PvmfwVerifyError::InvalidDescriptors(IoError::Io),
     )
 }
 
@@ -151,7 +152,7 @@
         &fs::read(TEST_IMG_WITH_DUPLICATED_CAP_PATH)?,
         /* initrd= */ None,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::InvalidMetadata.into(),
+        SlotVerifyError::InvalidMetadata.into(),
     )
 }
 
@@ -171,7 +172,7 @@
         &load_latest_signed_kernel()?,
         /* initrd= */ None,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::InvalidMetadata.into(),
+        SlotVerifyError::InvalidMetadata.into(),
     )
 }
 
@@ -181,7 +182,7 @@
         &load_latest_signed_kernel()?,
         &load_latest_initrd_normal()?,
         /* trusted_public_key= */ &[0u8; 0],
-        avb::SlotVerifyError::PublicKeyRejected.into(),
+        SlotVerifyError::PublicKeyRejected.into(),
     )
 }
 
@@ -191,7 +192,7 @@
         &load_latest_signed_kernel()?,
         &load_latest_initrd_normal()?,
         /* trusted_public_key= */ &[0u8; 512],
-        avb::SlotVerifyError::PublicKeyRejected.into(),
+        SlotVerifyError::PublicKeyRejected.into(),
     )
 }
 
@@ -201,7 +202,7 @@
         &load_latest_signed_kernel()?,
         &load_latest_initrd_normal()?,
         &fs::read(PUBLIC_KEY_RSA2048_PATH)?,
-        avb::SlotVerifyError::PublicKeyRejected.into(),
+        SlotVerifyError::PublicKeyRejected.into(),
     )
 }
 
@@ -211,7 +212,7 @@
         &load_latest_signed_kernel()?,
         /* initrd= */ &fs::read(UNSIGNED_TEST_IMG_PATH)?,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::Verification(None).into(),
+        SlotVerifyError::Verification(None).into(),
     )
 }
 
@@ -221,7 +222,7 @@
         &fs::read(UNSIGNED_TEST_IMG_PATH)?,
         &load_latest_initrd_normal()?,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::Io.into(),
+        SlotVerifyError::Io.into(),
     )
 }
 
@@ -234,7 +235,7 @@
         &kernel,
         &load_latest_initrd_normal()?,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::Verification(None).into(),
+        SlotVerifyError::Verification(None).into(),
     )
 }
 
@@ -272,7 +273,7 @@
             &kernel,
             &load_latest_initrd_normal()?,
             &load_trusted_public_key()?,
-            avb::SlotVerifyError::Io.into(),
+            SlotVerifyError::Io.into(),
         )?;
     }
     Ok(())
@@ -288,7 +289,7 @@
         &kernel,
         &load_latest_initrd_normal()?,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::InvalidMetadata.into(),
+        SlotVerifyError::InvalidMetadata.into(),
     )
 }
 
@@ -301,7 +302,7 @@
         &load_latest_signed_kernel()?,
         &initrd,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::Verification(None).into(),
+        SlotVerifyError::Verification(None).into(),
     )
 }
 
@@ -317,7 +318,7 @@
         &kernel,
         &load_latest_initrd_normal()?,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::InvalidMetadata.into(),
+        SlotVerifyError::InvalidMetadata.into(),
     )
 }
 
@@ -340,13 +341,13 @@
         &kernel,
         &load_latest_initrd_normal()?,
         &empty_public_key,
-        avb::SlotVerifyError::Verification(None).into(),
+        SlotVerifyError::Verification(None).into(),
     )?;
     assert_payload_verification_with_initrd_fails(
         &kernel,
         &load_latest_initrd_normal()?,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::Verification(None).into(),
+        SlotVerifyError::Verification(None).into(),
     )
 }
 
@@ -384,7 +385,7 @@
         &kernel,
         &load_latest_initrd_normal()?,
         &load_trusted_public_key()?,
-        avb::SlotVerifyError::Verification(None).into(),
+        SlotVerifyError::Verification(None).into(),
     )
 }