x86, 386 removal: Remove CONFIG_X86_WP_WORKS_OK

All 486+ CPUs support WP in supervisor mode, so remove the fallback
386 support code.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1354132230-21854-7-git-send-email-hpa@linux.intel.com

4 files changed, 1 insertions, 106 deletions

diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu
index d3bdc18af1f0..159ee9c824c9 100644
--- a/arch/x86/Kconfig.cpu
+++ b/arch/x86/Kconfig.cpu
@@ -325,9 +325,6 @@ config X86_INVD_BUG
         def_bool y
         depends on M486
 
-config X86_WP_WORKS_OK
-        def_bool y
-
 config X86_POPAD_OK
         def_bool y
         depends on X86_32
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 7ccf8d131535..1709801d18ec 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -237,8 +237,6 @@ extern void __put_user_2(void);
 extern void __put_user_4(void);
 extern void __put_user_8(void);
 
-#ifdef CONFIG_X86_WP_WORKS_OK
-
 /**
  * put_user: - Write a simple value into user space.
  * @x:   Value to copy to user space.
@@ -326,29 +324,6 @@ do {									\
         }                                                               \
 } while (0)
 
-#else
-
-#define __put_user_size(x, ptr, size, retval, errret)                   \
-do {                                                                    \
-        __typeof__(*(ptr))__pus_tmp = x;                                \
-        retval = 0;                                                     \
-                                                                        \
-        if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0))    \
-                retval = errret;                                        \
-} while (0)
-
-#define put_user(x, ptr)                                        \
-({                                                              \
-        int __ret_pu;                                           \
-        __typeof__(*(ptr))__pus_tmp = x;                        \
-        __ret_pu = 0;                                           \
-        if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp,         \
-                                       sizeof(*(ptr))) != 0))   \
-                __ret_pu = -EFAULT;                             \
-        __ret_pu;                                               \
-})
-#endif
-
 #ifdef CONFIG_X86_32
 #define __get_user_asm_u64(x, ptr, retval, errret)      (x) = __get_user_bad()
 #define __get_user_asm_ex_u64(x, ptr)                   (x) = __get_user_bad()
@@ -543,29 +518,12 @@ struct __large_struct { unsigned long buf[100]; };
         (x) = (__force __typeof__(*(ptr)))__gue_val;                    \
 } while (0)
 
-#ifdef CONFIG_X86_WP_WORKS_OK
-
 #define put_user_try            uaccess_try
 #define put_user_catch(err)     uaccess_catch(err)
 
 #define put_user_ex(x, ptr)                                             \
         __put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
 
-#else /* !CONFIG_X86_WP_WORKS_OK */
-
-#define put_user_try            do {            \
-        int __uaccess_err = 0;
-
-#define put_user_catch(err)                     \
-        (err) |= __uaccess_err;                 \
-} while (0)
-
-#define put_user_ex(x, ptr)     do {            \
-        __uaccess_err |= __put_user(x, ptr);    \
-} while (0)
-
-#endif /* CONFIG_X86_WP_WORKS_OK */
-
 extern unsigned long
 copy_from_user_nmi(void *to, const void __user *from, unsigned long n);
 extern __must_check long
diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c
index 98f6d6b68f5a..f0312d746402 100644
--- a/arch/x86/lib/usercopy_32.c
+++ b/arch/x86/lib/usercopy_32.c
@@ -570,63 +570,6 @@ do {									\
 unsigned long __copy_to_user_ll(void __user *to, const void *from,
                                 unsigned long n)
 {
-#ifndef CONFIG_X86_WP_WORKS_OK
-        if (unlikely(boot_cpu_data.wp_works_ok == 0) &&
-                        ((unsigned long)to) < TASK_SIZE) {
-                /*
-                 * When we are in an atomic section (see
-                 * mm/filemap.c:file_read_actor), return the full
-                 * length to take the slow path.
-                 */
-                if (in_atomic())
-                        return n;
-
-                /*
-                 * CPU does not honor the WP bit when writing
-                 * from supervisory mode, and due to preemption or SMP,
-                 * the page tables can change at any time.
-                 * Do it manually.      Manfred <manfred@colorfullife.com>
-                 */
-                while (n) {
-                        unsigned long offset = ((unsigned long)to)%PAGE_SIZE;
-                        unsigned long len = PAGE_SIZE - offset;
-                        int retval;
-                        struct page *pg;
-                        void *maddr;
-
-                        if (len > n)
-                                len = n;
-
-survive:
-                        down_read(&current->mm->mmap_sem);
-                        retval = get_user_pages(current, current->mm,
-                                        (unsigned long)to, 1, 1, 0, &pg, NULL);
-
-                        if (retval == -ENOMEM && is_global_init(current)) {
-                                up_read(&current->mm->mmap_sem);
-                                congestion_wait(BLK_RW_ASYNC, HZ/50);
-                                goto survive;
-                        }
-
-                        if (retval != 1) {
-                                up_read(&current->mm->mmap_sem);
-                                break;
-                        }
-
-                        maddr = kmap_atomic(pg);
-                        memcpy(maddr + offset, from, len);
-                        kunmap_atomic(maddr);
-                        set_page_dirty_lock(pg);
-                        put_page(pg);
-                        up_read(&current->mm->mmap_sem);
-
-                        from += len;
-                        to += len;
-                        n -= len;
-                }
-                return n;
-        }
-#endif
         stac();
         if (movsl_is_ok(to, from, n))
                 __copy_user(to, from, n);
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 11a58001b4ce..745d66b843c8 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -715,10 +715,7 @@ static void __init test_wp_bit(void)
 
         if (!boot_cpu_data.wp_works_ok) {
                 printk(KERN_CONT "No.\n");
-#ifdef CONFIG_X86_WP_WORKS_OK
-                panic(
-  "This kernel doesn't support CPU's with broken WP. Recompile it for a 386!");
-#endif
+                panic("Linux doesn't support CPUs with broken WP.");
         } else {
                 printk(KERN_CONT "Ok.\n");
         }