diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/x86_64/lib/putuser.S |
Linux-2.6.12-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.S | 89 |
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 00000000000..0dee1fdcb16 --- /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 |