[feat] update allocator version to support alloc_pages_at (#34)

* [feat] update allocator version to support alloc_pages_at
* [feat] set phys-virt-offset as 0xffff_8000_0000_0000 for x86_64 qemu

Author: hky1999

Cargo.toml

@@ -63,5 +63,7 @@ axsync = { path = "modules/axsync" }
 axtask = { path = "modules/axtask" }
 axdma = { path = "modules/axdma" }
 
+allocator = { git = "https://github.com/arceos-org/allocator.git", tag = "v0.1.1" }
+
 [profile.release]
 lto = true

modules/axalloc/src/lib.rs

@@ -146,6 +146,24 @@ impl GlobalAllocator {
         self.palloc.lock().alloc_pages(num_pages, align_pow2)
     }
 
+    /// Allocates contiguous pages starting from the given address.
+    ///
+    /// It allocates `num_pages` pages from the page allocator starting from the
+    /// given address.
+    ///
+    /// `align_pow2` must be a power of 2, and the returned region bound will be
+    /// aligned to it.
+    pub fn alloc_pages_at(
+        &self,
+        start: usize,
+        num_pages: usize,
+        align_pow2: usize,
+    ) -> AllocResult<usize> {
+        self.palloc
+            .lock()
+            .alloc_pages_at(start, num_pages, align_pow2)
+    }
+
     /// Gives back the allocated pages starts from `pos` to the page allocator.
     ///
     /// The pages should be allocated by [`alloc_pages`], and `align_pow2`