xnu-6153.11.26.tar.gz

[apple/xnu.git] / osfmk / kern / misc_protos.h

diff --git a/osfmk/kern/misc_protos.h b/osfmk/kern/misc_protos.h
index c1dee4267321a63a45a23f2c5c0f30ea98df17d0..a2585e4731d5c7617291dfa0e832eedb636e22c8 100644 (file)
--- a/osfmk/kern/misc_protos.h
+++ b/osfmk/kern/misc_protos.h
@@ -86,17 +86,44 @@ extern int testbit(
        int             which,
        int             *bitmap);
 
-/* Move an aligned 32 or 64-bit word from user space to kernel space
+/*
+ * Move an aligned 32 or 64-bit word from user space to kernel space
  * using a single read instruction
+ */
+extern int copyin_atomic32(
+       const user_addr_t   user_addr,
+       uint32_t            *kernel_addr);
+
+extern int copyin_atomic64(
+       const user_addr_t   user_addr,
+       uint64_t            *kernel_addr);
+
+/*
+ * Does an atomic copyin at the specified user_address and compares
+ * it to the passed in value, and if it matches, waits.
  *
- * when reading a 32-bit word, the value is 0-extended into the kernel space
- * 64-bit buffer passed as `kernel_addr`
- * (think `*kernel_addr = *(uint32_t *)user_addr`)
+ * This is used to implement adaptive spinning for userspace synchronization
+ *
+ * Returns:
+ * 0:       the value mached, and it paused efficiently for the platform
+ * ESTALE:  the value didn't match, and it returned immediately
+ * other:   the copyin failed (EFAULT, EINVAL, ...)
  */
-extern int copyin_word(
+extern int copyin_atomic32_wait_if_equals(
        const user_addr_t   user_addr,
-       uint64_t            *kernel_addr,
-       vm_size_t           nbytes);
+       uint32_t            value);
+
+/*
+ * Move a 32 or 64-bit word from kernel space to user space
+ * using a single write instruction
+ */
+extern int copyout_atomic32(
+       uint32_t            u32,
+       user_addr_t         user_addr);
+
+extern int copyout_atomic64(
+       uint64_t            u64,
+       user_addr_t         user_addr);
 
 /* Move a NUL-terminated string from a user space to kernel space */
 extern int copyinstr(
@@ -121,9 +148,6 @@ extern int copyoutmsg(
 extern void inval_copy_windows(thread_t);
 extern void copy_window_fault(thread_t, vm_map_t, int);
 
-extern int copyin_validate(const user_addr_t, uintptr_t, vm_size_t);
-extern int copyout_validate(uintptr_t, const user_addr_t, vm_size_t);
-
 extern int sscanf(const char *input, const char *fmt, ...) __scanflike(2, 3);
 
 /* sprintf() is being deprecated. Please use snprintf() instead. */