fix: 初始映射多映点

Signed-off-by: YdrMaster <[email protected]>
rcore-os · Sep 5, 2022 · 227956d · 227956d
1 parent 5b4b399
commit 227956d
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Showing 7 changed files with 27 additions and 47 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/xtask/src/build.rs b/xtask/src/build.rs
@@ -134,7 +134,7 @@ impl QemuArgs {
         .bin();
         // 设置 Qemu 参数
         let mut qemu = Qemu::system(arch_str);
-        qemu.args(&["-m", "1G"])
+        qemu.args(&["-m", "2G"])
             .arg("-kernel")
             .arg(&bin)
             .arg("-initrd")

diff --git a/zCore/Cargo.toml b/zCore/Cargo.toml
@@ -75,7 +75,7 @@ buddy_system_allocator = "0.8"
 r0 = "1"
 riscv = "0.8"
 dtb-walker = "=0.2.0-alpha.3"
-page-table = "0.0.2"
+page-table = "0.0.4"
 sbi-rt = { git = "https://github.com/rustsbi/sbi-rt.git", rev = "2933f8d" }
 
 # Bare-metal mode on x86_64

diff --git a/zCore/src/memory.rs b/zCore/src/memory.rs
@@ -10,7 +10,7 @@ use lock::Mutex;
 type FrameAlloc = bitmap_allocator::BitAlloc16M; // max 64G
 
 #[cfg(target_arch = "riscv64")]
-type FrameAlloc = bitmap_allocator::BitAlloc1M; // max 4G
+type FrameAlloc = bitmap_allocator::BitAlloc16M; // max 4G
 
 #[cfg(target_arch = "aarch64")]
 type FrameAlloc = bitmap_allocator::BitAlloc1M; // max 4G

diff --git a/zCore/src/platform/riscv/boot_page_table.rs b/zCore/src/platform/riscv/boot_page_table.rs
@@ -1,57 +1,37 @@
 use super::consts::{kernel_mem_info, kernel_mem_probe};
 use core::arch::asm;
-use page_table::{MmuFlags, PageTable, Sv39, OFFSET_BITS, PPN};
-
-/// 内核页属性
-const KERNEL_PAGE: MmuFlags<Sv39> = MmuFlags::new(0xef); // DAG_'XWRV
-
-/// 子页表属性
-const SUBTABLE: MmuFlags<Sv39> = MmuFlags::new(0x21); // __G_'___V
+use page_table::{MmuFlags, PageTable, Sv39, VAddr, OFFSET_BITS, PPN};
 
 /// 启动页表。
-pub(super) struct BootPageTable {
-    root: PageTable<Sv39>,
-    sub: PageTable<Sv39>,
-}
+#[repr(align(4096))]
+pub(super) struct BootPageTable(PageTable<Sv39>);
+
+/// 内核页属性
+const DAGXWRV: MmuFlags<Sv39> = MmuFlags::new(0xef);
 
 impl BootPageTable {
     /// 初始化为全零的启动页表。
-    pub const ZERO: Self = Self {
-        root: PageTable::ZERO,
-        sub: PageTable::ZERO,
-    };
+    pub const ZERO: Self = Self(PageTable::ZERO);
 
     /// 根据内核实际位置初始化启动页表。
     pub fn init(&mut self) {
         // 启动页表初始化之前 pc 必定在物理地址空间
         // 因此可以安全地定位内核地址信息
         let mem_info = unsafe { kernel_mem_probe() };
-        let pbase = mem_info.paddr_base;
-        let vbase = mem_info.vaddr_base;
+        let paddr_base = mem_info.paddr_base & MASK1G;
+        let vaddr_base = mem_info.vaddr_base & MASK1G;
+        const MASK1G: usize = !((1 << 30) - 1);
 
-        const GIB_MASK: usize = !((1 << 30) - 1);
-        const SIZE_2MIB: usize = 1 << 21;
-        const MASK_2MIB: usize = !(SIZE_2MIB - 1);
-        {
-            // 把内核起始位置到其所在 GiB 页的末尾映射到虚拟地址空间
-            let mut p = (pbase & MASK_2MIB)..((pbase & GIB_MASK) + (1 << 30));
-            let mut v = vbase & MASK_2MIB;
-            while !p.is_empty() {
-                let entry = KERNEL_PAGE.build_pte(PPN(p.start >> OFFSET_BITS));
-                self.sub.set_entry(v.into(), entry, 1).unwrap();
-                p.start += SIZE_2MIB;
-                v += SIZE_2MIB;
-            }
+        // 内核 GiB 页表项
+        let pte = DAGXWRV.build_pte(PPN(paddr_base >> OFFSET_BITS));
+        // 映射内核页和跳板页
+        self.0.set_entry(VAddr::new(paddr_base), pte, 2).unwrap();
+        for i in 0..64 {
+            let paddr = paddr_base + (i << 30);
+            let vaddr = vaddr_base + (i << 30);
+            let pte = DAGXWRV.build_pte(PPN(paddr >> OFFSET_BITS));
+            self.0.set_entry(VAddr::new(vaddr), pte, 2).unwrap();
         }
-        // 映射跳板页和内核页
-        let raw = KERNEL_PAGE.build_pte(PPN((pbase & GIB_MASK) >> OFFSET_BITS));
-        let sub = SUBTABLE.build_pte(PPN(self.sub.as_ptr() as usize >> OFFSET_BITS));
-        self.root
-            .set_entry((pbase & GIB_MASK).into(), raw, 2)
-            .unwrap();
-        self.root
-            .set_entry((vbase & GIB_MASK).into(), sub, 2)
-            .unwrap();
     }
 
     /// 启动地址转换，跃迁到高地址，并设置线程指针和内核对用户页的访问权限。
@@ -66,7 +46,7 @@ impl BootPageTable {
         satp::set(
             satp::Mode::Sv39,
             0,
-            self.root.as_ptr() as usize >> OFFSET_BITS,
+            self as *const _ as usize >> OFFSET_BITS,
         );
         // 此时原本的地址空间还在，所以不用刷快表
         // riscv::asm::sfence_vma_all();

diff --git a/zCore/src/platform/riscv/consts.rs b/zCore/src/platform/riscv/consts.rs
@@ -45,7 +45,7 @@ impl KernelMemInfo {
             fn end();
         }
         let paddr_base = start as usize;
-        let vaddr_base = ((!0) << 30) + (paddr_base & ((1 << 21) - 1));
+        let vaddr_base = 0xffff_ffe0_0020_0000;
         Self {
             paddr_base,
             vaddr_base,

diff --git a/zCore/src/platform/riscv/linker.ld b/zCore/src/platform/riscv/linker.ld
@@ -1,6 +1,6 @@
 OUTPUT_ARCH(riscv)
 ENTRY(_start)
-BASE_ADDRESS = 0xffffffffc0000000;
+BASE_ADDRESS = 0xffffffe000200000;
 SECTIONS
 {
     . = BASE_ADDRESS;