summaryrefslogtreecommitdiffstats
path: root/arch/x86_64/lib/putuser.S
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/x86_64/lib/putuser.S
downloadop-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/x86_64/lib/putuser.S')
-rw-r--r--arch/x86_64/lib/putuser.S89
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/x86_64/lib/putuser.S b/arch/x86_64/lib/putuser.S
new file mode 100644
index 0000000..0dee1fd
--- /dev/null
+++ b/arch/x86_64/lib/putuser.S
@@ -0,0 +1,89 @@
+/*
+ * __put_user functions.
+ *
+ * (C) Copyright 1998 Linus Torvalds
+ * (C) Copyright 2005 Andi Kleen
+ *
+ * These functions have a non-standard call interface
+ * to make them more efficient, especially as they
+ * return an error value in addition to the "real"
+ * return value.
+ */
+
+/*
+ * __put_user_X
+ *
+ * Inputs: %rcx contains the address
+ * %rdx contains new value
+ *
+ * Outputs: %rax is error code (0 or -EFAULT)
+ *
+ * %r8 is destroyed.
+ *
+ * These functions should not modify any other registers,
+ * as they get called from within inline assembly.
+ */
+
+#include <linux/linkage.h>
+#include <asm/page.h>
+#include <asm/errno.h>
+#include <asm/offset.h>
+#include <asm/thread_info.h>
+
+ .text
+ .p2align 4
+.globl __put_user_1
+__put_user_1:
+ GET_THREAD_INFO(%r8)
+ cmpq threadinfo_addr_limit(%r8),%rcx
+ jae bad_put_user
+1: movb %dl,(%rcx)
+ xorl %eax,%eax
+ ret
+
+ .p2align 4
+.globl __put_user_2
+__put_user_2:
+ GET_THREAD_INFO(%r8)
+ addq $1,%rcx
+ jc bad_put_user
+ cmpq threadinfo_addr_limit(%r8),%rcx
+ jae bad_put_user
+2: movw %dx,-1(%rcx)
+ xorl %eax,%eax
+ ret
+
+ .p2align 4
+.globl __put_user_4
+__put_user_4:
+ GET_THREAD_INFO(%r8)
+ addq $3,%rcx
+ jc bad_put_user
+ cmpq threadinfo_addr_limit(%r8),%rcx
+ jae bad_put_user
+3: movl %edx,-3(%rcx)
+ xorl %eax,%eax
+ ret
+
+ .p2align 4
+.globl __put_user_8
+__put_user_8:
+ GET_THREAD_INFO(%r8)
+ addq $7,%rcx
+ jc bad_put_user
+ cmpq threadinfo_addr_limit(%r8),%rcx
+ jae bad_put_user
+4: movq %rdx,-7(%rcx)
+ xorl %eax,%eax
+ ret
+
+bad_put_user:
+ movq $(-EFAULT),%rax
+ ret
+
+.section __ex_table,"a"
+ .quad 1b,bad_put_user
+ .quad 2b,bad_put_user
+ .quad 3b,bad_put_user
+ .quad 4b,bad_put_user
+.previous
OpenPOWER on IntegriCloud