Add kernel-writing functions for guru only

* runtime/loc2c-runtime.h (store_deref_string): New.
* tapset/conversions-guru.stp (set_kernel_*): New guru functions.

2 files changed, 128 insertions, 0 deletions

diff --git a/runtime/loc2c-runtime.h b/runtime/loc2c-runtime.h
index c75639ee..bd1faa51 100644
--- a/runtime/loc2c-runtime.h
+++ b/runtime/loc2c-runtime.h
@@ -1011,6 +1011,17 @@ extern void __store_deref_bad(void);
     (dst);								      \
   })
 
+#define store_deref_string(src, addr, maxbytes)				      \
+  ({									      \
+    uintptr_t _addr;							      \
+    size_t _len;							      \
+    char *_s = (src);							      \
+    for (_len = (maxbytes), _addr = (uintptr_t)(addr);			      \
+	 _len > 1 && _s && *_s != '\0'; --_len, ++_addr)		      \
+      store_deref(1, _addr, *_s++);					      \
+    store_deref(1, _addr, '\0');					      \
+  })
+
 #define CATCH_DEREF_FAULT()				\
   if (0) {						\
 deref_fault: ;						\
diff --git a/tapset/conversions-guru.stp b/tapset/conversions-guru.stp
new file mode 100644
index 00000000..f914bb31
--- /dev/null
+++ b/tapset/conversions-guru.stp
@@ -0,0 +1,117 @@
+// guru-mode conversions tapset
+// Copyright (C) 2010 Red Hat Inc.
+//
+// This file is part of systemtap, and is free software.  You can
+// redistribute it and/or modify it under the terms of the GNU General
+// Public License (GPL); either version 2, or (at your option) any
+// later version.
+
+/**
+ * sfunction set_kernel_string - Writes a string to kernel memory.
+ * @addr: The kernel address to write the string to.
+ * @val: The string which is to be written.
+ *
+ * Description: Writes the given string to a given kernel
+ * memory address. Reports an error on string copy fault.
+ */
+function set_kernel_string (addr:long, val:string) %{ /* guru */
+  store_deref_string (THIS->val, THIS->addr, MAXSTRINGLEN);
+  if (0) {
+deref_fault: /* branched to from store_deref_string() */
+    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
+        "kernel string copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
+    CONTEXT->last_error = CONTEXT->error_buffer;
+  }
+%}
+
+/**
+ * sfunction set_kernel_string_n - Writes a string of given length to kernel memory.
+ * @addr: The kernel address to write the string to.
+ * @n: The maximum length of the string.
+ * @val: The string which is to be written.
+ *
+ * Description: Writes the given string up to a maximum given length to a
+ * given kernel memory address. Reports an error on string copy fault.
+ */
+function set_kernel_string_n (addr:long, n:long, val:string) %{ /* guru */
+  int64_t len = clamp_t(int64_t, THIS->n + 1, 1, MAXSTRINGLEN);
+  store_deref_string (THIS->val, THIS->addr, len);
+  if (0) {
+deref_fault: /* branched to from store_deref_string() */
+    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
+        "kernel string copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
+    CONTEXT->last_error = CONTEXT->error_buffer;
+  }
+%}
+
+/**
+ * sfunction set_kernel_long - Writes a long value to kernel memory.
+ * @addr: The kernel address to write the long to.
+ * @val: The long which is to be written.
+ *
+ * Description: Writes the long value to a given kernel memory address.
+ * Reports an error when writing to the given address fails.
+ */
+function set_kernel_long (addr:long, val:long) %{ /* guru */
+  kwrite((long *) (intptr_t) THIS->addr, THIS->val);
+  if (0) {
+deref_fault: /* branched to from kwrite() */
+    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
+        "kernel long copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
+    CONTEXT->last_error = CONTEXT->error_buffer;
+  }
+%}
+
+/**
+ * sfunction set_kernel_int - Writes an int value to kernel memory.
+ * @addr: The kernel address to write the int to.
+ * @val: The int which is to be written.
+ *
+ * Description: Writes the int value to a given kernel memory address.
+ * Reports an error when writing to the given address fails.
+ */
+function set_kernel_int (addr:long, val:long) %{ /* guru */
+  kwrite((int *) (intptr_t) THIS->addr, THIS->val);
+  if (0) {
+deref_fault: /* branched to from kwrite() */
+    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
+        "kernel int copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
+    CONTEXT->last_error = CONTEXT->error_buffer;
+  }
+%}
+
+/**
+ * sfunction set_kernel_short - Writes a short value to kernel memory.
+ * @addr: The kernel address to write the short to.
+ * @val: The short which is to be written.
+ *
+ * Description: Writes the short value to a given kernel memory address.
+ * Reports an error when writing to the given address fails.
+ */
+function set_kernel_short (addr:long, val:long) %{ /* guru */
+  kwrite((short *) (intptr_t) THIS->addr, THIS->val);
+  if (0) {
+deref_fault: /* branched to from kwrite() */
+    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
+        "kernel short copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
+    CONTEXT->last_error = CONTEXT->error_buffer;
+  }
+%}
+
+/**
+ * sfunction set_kernel_char - Writes a char value to kernel memory.
+ * @addr: The kernel address to write the char to.
+ * @val: The char which is to be written.
+ *
+ * Description: Writes the char value to a given kernel memory address.
+ * Reports an error when writing to the given address fails.
+ */
+function set_kernel_char (addr:long, val:long) %{ /* guru */
+  kwrite((char *) (intptr_t) THIS->addr, THIS->val);
+  if (0) {
+deref_fault: /* branched to from kwrite() */
+    snprintf (CONTEXT->error_buffer, sizeof(CONTEXT->error_buffer),
+        "kernel char copy fault at 0x%p", (void *) (uintptr_t) THIS->addr);
+    CONTEXT->last_error = CONTEXT->error_buffer;
+  }
+%}