Make VolatileSlice ABI-compatible with iovec

Change VolatileSlice so that it is ABI-compatible with iovec.  This
allows us to directly pass in a VolatileSlice for a C function that
expects an iovec without having to create temporaries that convert from
one to the other.

Also change all the parameters from u64 to usize.  It's not possible to
address more memory than fits into a usize so having u64 here didn't
really provide much benefit and led to a lot of tedious casting back and
forth all over the place.

BUG=none
TEST=unit tests

Cq-Depend: chromium:2206621
Change-Id: I258f9123c603d9a4c6c5e2d4d10eb4aedf74466d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/2203998
Tested-by: Chirantan Ekbote <chirantan@chromium.org>
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Commit-Queue: Chirantan Ekbote <chirantan@chromium.org>

1 files changed, 7 insertions, 7 deletions

diff --git a/gpu_renderer/src/lib.rs b/gpu_renderer/src/lib.rs
index 1db066c..9cdb5a3 100644
--- a/gpu_renderer/src/lib.rs
+++ b/gpu_renderer/src/lib.rs
@@ -23,7 +23,7 @@ use std::sync::atomic::{AtomicBool, Ordering};
 
 use libc::close;
 
-use data_model::{VolatileMemory, VolatileSlice};
+use data_model::VolatileSlice;
 use sys_util::{debug, GuestAddress, GuestMemory};
 
 use crate::generated::p_defines::{
@@ -411,7 +411,7 @@ impl Renderer {
         {
             if vecs
                 .iter()
-                .any(|&(addr, len)| mem.get_slice(addr.offset(), len as u64).is_err())
+                .any(|&(addr, len)| mem.get_slice_at_addr(addr, len).is_err())
             {
                 return Err(Error::InvalidIovec);
             }
@@ -419,9 +419,9 @@ impl Renderer {
             let mut iovecs = Vec::new();
             for &(addr, len) in vecs {
                 // Unwrap will not panic because we already checked the slices.
-                let slice = mem.get_slice(addr.offset(), len as u64).unwrap();
+                let slice = mem.get_slice_at_addr(addr, len).unwrap();
                 iovecs.push(VirglVec {
-                    base: slice.as_ptr() as *mut c_void,
+                    base: slice.as_mut_ptr() as *mut c_void,
                     len,
                 });
             }
@@ -591,7 +591,7 @@ impl Resource {
     ) -> Result<()> {
         if iovecs
             .iter()
-            .any(|&(addr, len)| mem.get_slice(addr.offset(), len as u64).is_err())
+            .any(|&(addr, len)| mem.get_slice_at_addr(addr, len).is_err())
         {
             return Err(Error::InvalidIovec);
         }
@@ -599,9 +599,9 @@ impl Resource {
         self.backing_mem = Some(mem.clone());
         for &(addr, len) in iovecs {
             // Unwrap will not panic because we already checked the slices.
-            let slice = mem.get_slice(addr.offset(), len as u64).unwrap();
+            let slice = mem.get_slice_at_addr(addr, len).unwrap();
             self.backing_iovecs.push(VirglVec {
-                base: slice.as_ptr() as *mut c_void,
+                base: slice.as_mut_ptr() as *mut c_void,
                 len,
             });
         }