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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /arch/x86/um/os-Linux/tls.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'arch/x86/um/os-Linux/tls.c')
-rw-r--r--arch/x86/um/os-Linux/tls.c67
1 files changed, 67 insertions, 0 deletions
diff --git a/arch/x86/um/os-Linux/tls.c b/arch/x86/um/os-Linux/tls.c
new file mode 100644
index 00000000..82276b60
--- /dev/null
+++ b/arch/x86/um/os-Linux/tls.c
@@ -0,0 +1,67 @@
+#include <errno.h>
+#include <linux/unistd.h>
+
+#include <sys/ptrace.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+#include "sysdep/tls.h"
+
+#ifndef PTRACE_GET_THREAD_AREA
+#define PTRACE_GET_THREAD_AREA 25
+#endif
+
+#ifndef PTRACE_SET_THREAD_AREA
+#define PTRACE_SET_THREAD_AREA 26
+#endif
+
+/* Checks whether host supports TLS, and sets *tls_min according to the value
+ * valid on the host.
+ * i386 host have it == 6; x86_64 host have it == 12, for i386 emulation. */
+void check_host_supports_tls(int *supports_tls, int *tls_min)
+{
+ /* Values for x86 and x86_64.*/
+ int val[] = {GDT_ENTRY_TLS_MIN_I386, GDT_ENTRY_TLS_MIN_X86_64};
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(val); i++) {
+ user_desc_t info;
+ info.entry_number = val[i];
+
+ if (syscall(__NR_get_thread_area, &info) == 0) {
+ *tls_min = val[i];
+ *supports_tls = 1;
+ return;
+ } else {
+ if (errno == EINVAL)
+ continue;
+ else if (errno == ENOSYS)
+ *supports_tls = 0;
+ return;
+ }
+ }
+
+ *supports_tls = 0;
+}
+
+int os_set_thread_area(user_desc_t *info, int pid)
+{
+ int ret;
+
+ ret = ptrace(PTRACE_SET_THREAD_AREA, pid, info->entry_number,
+ (unsigned long) info);
+ if (ret < 0)
+ ret = -errno;
+ return ret;
+}
+
+int os_get_thread_area(user_desc_t *info, int pid)
+{
+ int ret;
+
+ ret = ptrace(PTRACE_GET_THREAD_AREA, pid, info->entry_number,
+ (unsigned long) info);
+ if (ret < 0)
+ ret = -errno;
+ return ret;
+}