feat: COW

Cargo.toml

@@ -26,7 +26,7 @@ axconfig = { git = "https://github.com/oscomp/arceos.git" }
 axfs = { git = "https://github.com/oscomp/arceos.git" }
 axhal = { git = "https://github.com/oscomp/arceos.git", features = ["uspace"] }
 axlog = { git = "https://github.com/oscomp/arceos.git" }
-axmm = { git = "https://github.com/oscomp/arceos.git" }
+axmm = { git = "https://github.com/oscomp/arceos.git", features = ["cow"] }
 axnet = { git = "https://github.com/oscomp/arceos.git" }
 axns = { git = "https://github.com/oscomp/arceos.git", features = [
     "thread-local",
@@ -90,5 +90,5 @@ shlex = { version = "1.3.0", default-features = false }
 syscalls = { git = "https://github.com/jasonwhite/syscalls.git", rev = "92624de", default-features = false }
 
 [patch.crates-io]
-page_table_multiarch = { git = "https://github.com/Mivik/page_table_multiarch.git", rev = "19ededd" }
-page_table_entry = { git = "https://github.com/Mivik/page_table_multiarch.git", rev = "19ededd" }
+page_table_multiarch = { git = "https://github.com/Mivik/page_table_multiarch.git", rev = "5c222f2" }
+page_table_entry = { git = "https://github.com/Mivik/page_table_multiarch.git", rev = "5c222f2" }

apps/libc/c/forkcow/forkcow.c

@@ -0,0 +1,51 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <sys/mman.h>
+
+#define N 150
+#define LEN (1024 * 1024)
+
+void forktest(void) {
+  int n, pid;
+
+  printf("fork test\n");
+
+  char *ptr = mmap(NULL, LEN * sizeof(char), PROT_READ | PROT_WRITE,
+                  MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+  for (n = 0; n < LEN; n++) {
+      *(ptr + n) = 'a';
+  }
+
+  for (n = 0; n < N; n++) {
+    pid = fork();
+    if (pid < 0)
+      break;
+    if (pid == 0)
+      exit(0);
+  }
+
+  if (n == N) {
+    printf("fork test OK\n");
+    exit(0);
+  }
+
+  for (; n > 0; n--) {
+    if (wait(0) < 0) {
+      printf("wait stopped early\n");
+      exit(1);
+    }
+  }
+
+  if (wait(0) != -1) {
+    printf("wait got too many\n");
+    exit(1);
+  }
+}
+
+int main(void) {
+  forktest();
+  exit(1);
+}

apps/libc/expect_off.out

@@ -22,3 +22,6 @@ test_sigwait ok3
 test_sigsuspend ok1
 test_sigsuspend ok2
 test_sigsuspend ok3
+
+fork test
+fork test OK

apps/libc/testcase_list

@@ -1,4 +1,5 @@
 helloworld_c
 sleep_c
 signal_c
+forkcow_c
 mmap_c

scripts/get_deps.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 
 AX_ROOT=.arceos
-COMMIT=54d5739
+COMMIT=a634925
 test ! -d "$AX_ROOT" && echo "Cloning repositories ..." || true
 test ! -d "$AX_ROOT" && git clone https://github.com/oscomp/arceos "$AX_ROOT" || true