--- /dev/null
+/*
+ * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <init.h>
+#include <as-layout.h>
+#include <mm_id.h>
+#include <os.h>
+#include <ptrace_user.h>
+#include <registers.h>
+#include <skas.h>
+#include <sysdep/ptrace.h>
+#include <sysdep/stub.h>
+
+extern unsigned long batch_syscall_stub, __syscall_stub_start;
+
+extern void wait_stub_done(int pid);
+
+static inline unsigned long *check_init_stack(struct mm_id * mm_idp,
+ unsigned long *stack)
+{
+ if (stack == NULL) {
+ stack = (unsigned long *) mm_idp->stack + 2;
+ *stack = 0;
+ }
+ return stack;
+}
+
+static unsigned long syscall_regs[MAX_REG_NR];
+
+static int __init init_syscall_regs(void)
+{
+ get_safe_registers(syscall_regs, NULL);
+ syscall_regs[REGS_IP_INDEX] = STUB_CODE +
+ ((unsigned long) &batch_syscall_stub -
+ (unsigned long) &__syscall_stub_start);
+ return 0;
+}
+
+__initcall(init_syscall_regs);
+
+static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr)
+{
+ int n, i;
+ long ret, offset;
+ unsigned long * data;
+ unsigned long * syscall;
+ int err, pid = mm_idp->u.pid;
+
+ n = ptrace_setregs(pid, syscall_regs);
+ if (n < 0) {
+ printk(UM_KERN_ERR "Registers - \n");
+ for (i = 0; i < MAX_REG_NR; i++)
+ printk(UM_KERN_ERR "\t%d\t0x%lx\n", i, syscall_regs[i]);
+ panic("do_syscall_stub : PTRACE_SETREGS failed, errno = %d\n",
+ -n);
+ }
+
+ err = ptrace(PTRACE_CONT, pid, 0, 0);
+ if (err)
+ panic("Failed to continue stub, pid = %d, errno = %d\n", pid,
+ errno);
+
+ wait_stub_done(pid);
+
+ /*
+ * When the stub stops, we find the following values on the
+ * beginning of the stack:
+ * (long )return_value
+ * (long )offset to failed sycall-data (0, if no error)
+ */
+ ret = *((unsigned long *) mm_idp->stack);
+ offset = *((unsigned long *) mm_idp->stack + 1);
+ if (offset) {
+ data = (unsigned long *)(mm_idp->stack + offset - STUB_DATA);
+ printk(UM_KERN_ERR "do_syscall_stub : ret = %ld, offset = %ld, "
+ "data = %p\n", ret, offset, data);
+ syscall = (unsigned long *)((unsigned long)data + data[0]);
+ printk(UM_KERN_ERR "do_syscall_stub: syscall %ld failed, "
+ "return value = 0x%lx, expected return value = 0x%lx\n",
+ syscall[0], ret, syscall[7]);
+ printk(UM_KERN_ERR " syscall parameters: "
+ "0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
+ syscall[1], syscall[2], syscall[3],
+ syscall[4], syscall[5], syscall[6]);
+ for (n = 1; n < data[0]/sizeof(long); n++) {
+ if (n == 1)
+ printk(UM_KERN_ERR " additional syscall "
+ "data:");
+ if (n % 4 == 1)
+ printk("\n" UM_KERN_ERR " ");
+ printk(" 0x%lx", data[n]);
+ }
+ if (n > 1)
+ printk("\n");
+ }
+ else ret = 0;
+
+ *addr = check_init_stack(mm_idp, NULL);
+
+ return ret;
+}
+
+long run_syscall_stub(struct mm_id * mm_idp, int syscall,
+ unsigned long *args, long expected, void **addr,
+ int done)
+{
+ unsigned long *stack = check_init_stack(mm_idp, *addr);
+
+ *stack += sizeof(long);
+ stack += *stack / sizeof(long);
+
+ *stack++ = syscall;
+ *stack++ = args[0];
+ *stack++ = args[1];
+ *stack++ = args[2];
+ *stack++ = args[3];
+ *stack++ = args[4];
+ *stack++ = args[5];
+ *stack++ = expected;
+ *stack = 0;
+
+ if (!done && ((((unsigned long) stack) & ~UM_KERN_PAGE_MASK) <
+ UM_KERN_PAGE_SIZE - 10 * sizeof(long))) {
+ *addr = stack;
+ return 0;
+ }
+
+ return do_syscall_stub(mm_idp, addr);
+}
+
+long syscall_stub_data(struct mm_id * mm_idp,
+ unsigned long *data, int data_count,
+ void **addr, void **stub_addr)
+{
+ unsigned long *stack;
+ int ret = 0;
+
+ /*
+ * If *addr still is uninitialized, it *must* contain NULL.
+ * Thus in this case do_syscall_stub correctly won't be called.
+ */
+ if ((((unsigned long) *addr) & ~UM_KERN_PAGE_MASK) >=
+ UM_KERN_PAGE_SIZE - (10 + data_count) * sizeof(long)) {
+ ret = do_syscall_stub(mm_idp, addr);
+ /* in case of error, don't overwrite data on stack */
+ if (ret)
+ return ret;
+ }
+
+ stack = check_init_stack(mm_idp, *addr);
+ *addr = stack;
+
+ *stack = data_count * sizeof(long);
+
+ memcpy(stack + 1, data, data_count * sizeof(long));
+
+ *stub_addr = (void *)(((unsigned long)(stack + 1) &
+ ~UM_KERN_PAGE_MASK) + STUB_DATA);
+
+ return 0;
+}
+
+int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len, int prot,
+ int phys_fd, unsigned long long offset, int done, void **data)
+{
+ int ret;
+ unsigned long args[] = { virt, len, prot,
+ MAP_SHARED | MAP_FIXED, phys_fd,
+ MMAP_OFFSET(offset) };
+
+ ret = run_syscall_stub(mm_idp, STUB_MMAP_NR, args, virt,
+ data, done);
+
+ return ret;
+}
+
+int unmap(struct mm_id * mm_idp, unsigned long addr, unsigned long len,
+ int done, void **data)
+{
+ int ret;
+ unsigned long args[] = { (unsigned long) addr, len, 0, 0, 0,
+ 0 };
+
+ ret = run_syscall_stub(mm_idp, __NR_munmap, args, 0,
+ data, done);
+
+ return ret;
+}
+
+int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len,
+ unsigned int prot, int done, void **data)
+{
+ int ret;
+ unsigned long args[] = { addr, len, prot, 0, 0, 0 };
+
+ ret = run_syscall_stub(mm_idp, __NR_mprotect, args, 0,
+ data, done);
+
+ return ret;
+}
Code Review / kvmfornfv.git / blobdiff