greq: use addr_of!() / addr_of_mut() instead of "as" casting

This makes code more explicit and clearer.

Signed-off-by: Carlos López <carlos.lopez@suse.com>

src/greq/driver.rs

@@ -11,6 +11,7 @@
 extern crate alloc;
 
 use alloc::boxed::Box;
+use core::ptr::addr_of_mut;
 use core::{cell::OnceCell, mem::size_of};
 
 use crate::{
@@ -158,9 +159,9 @@ impl SnpGuestRequestDriver {
     fn send(&mut self, req_class: SnpGuestRequestClass) -> Result<(), SvsmReqError> {
         self.response.clear();
 
-        let req_page = VirtAddr::from(&mut *self.request as *mut SnpGuestRequestMsg);
-        let resp_page = VirtAddr::from(&mut *self.response as *mut SnpGuestRequestMsg);
-        let data_pages = VirtAddr::from(&mut *self.ext_data as *mut SnpGuestRequestExtData);
+        let req_page = VirtAddr::from(addr_of_mut!(*self.request));
+        let resp_page = VirtAddr::from(addr_of_mut!(*self.response));
+        let data_pages = VirtAddr::from(addr_of_mut!(*self.ext_data));
 
         if req_class == SnpGuestRequestClass::Extended {
             let num_user_pages = (self.user_extdata_size >> PAGE_SHIFT) as u64;

src/greq/msg.rs

@@ -14,7 +14,7 @@ use alloc::{
 };
 use core::{
     mem::size_of,
-    ptr::addr_of,
+    ptr::{addr_of, addr_of_mut},
     slice::{from_raw_parts, from_raw_parts_mut, from_ref},
 };
 
@@ -175,7 +175,7 @@ impl SnpGuestRequestMsgHdr {
 
     /// Get [`SnpGuestRequestMsgHdr`] as a mutable slice reference
     fn as_slice_mut(&mut self) -> &mut [u8] {
-        unsafe { from_raw_parts_mut(self as *mut _ as *mut u8, size_of::<Self>()) }
+        unsafe { from_raw_parts_mut(addr_of_mut!(*self).cast(), size_of::<Self>()) }
     }
 }
 
@@ -244,7 +244,7 @@ impl SnpGuestRequestMsg {
     ///   before the object is dropped. Shared pages should not be freed
     ///   (returned to the allocator)
     pub fn set_shared(&mut self) -> Result<(), SvsmReqError> {
-        let vaddr = VirtAddr::from(self as *mut Self);
+        let vaddr = VirtAddr::from(addr_of!(*self));
         this_cpu_mut()
             .get_pgtable()
             .set_shared_4k(vaddr)
@@ -264,7 +264,7 @@ impl SnpGuestRequestMsg {
 
     /// Set the C-bit (memory encryption bit) for the Self page
     pub fn set_encrypted(&mut self) -> Result<(), SvsmReqError> {
-        let vaddr = VirtAddr::from(self as *mut Self);
+        let vaddr = VirtAddr::from(addr_of!(*self));
         this_cpu_mut()
             .get_pgtable()
             .set_encrypted_4k(vaddr)
@@ -505,14 +505,14 @@ impl SnpGuestRequestExtData {
     ///   before the object is dropped. Shared pages should not be freed
     ///   (returned to the allocator)
     pub fn set_shared(&mut self) -> Result<(), SvsmReqError> {
-        let start = VirtAddr::from(self as *mut Self);
+        let start = VirtAddr::from(addr_of!(*self));
         let end = start + size_of::<Self>();
         set_shared_region_4k(start, end)
     }
 
     /// Set the C-bit (memory encryption bit) for the Self pages
     pub fn set_encrypted(&mut self) -> Result<(), SvsmReqError> {
-        let start = VirtAddr::from(self as *mut Self);
+        let start = VirtAddr::from(addr_of!(*self));
         let end = start + size_of::<Self>();
         set_encrypted_region_4k(start, end)
     }