x86: some lock annotations for user copy paths, v2

 - introduce might_fault()
 - handle the atomic user copy paths correctly

[ mingo@elte.hu: move might_sleep() outside of in_atomic(). ]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 14 deletions

diff --git a/include/asm-x86/uaccess.h b/include/asm-x86/uaccess.h
index ad29752a1713..39f8420c75d9 100644
--- a/include/asm-x86/uaccess.h
+++ b/include/asm-x86/uaccess.h
@@ -8,8 +8,6 @@
 #include <linux/thread_info.h>
 #include <linux/prefetch.h>
 #include <linux/string.h>
-#include <linux/lockdep.h>
-#include <linux/sched.h>
 #include <asm/asm.h>
 #include <asm/page.h>
 
@@ -159,9 +157,7 @@ extern int __get_user_bad(void);
         int __ret_gu;                                                   \
         unsigned long __val_gu;                                         \
         __chk_user_ptr(ptr);                                            \
-        might_sleep();                                                  \
-        if (current->mm)                                                \
-                might_lock_read(&current->mm->mmap_sem);                \
+        might_fault();                                                  \
         switch (sizeof(*(ptr))) {                                       \
         case 1:                                                         \
                 __get_user_x(1, __ret_gu, __val_gu, ptr);               \
@@ -246,9 +242,7 @@ extern void __put_user_8(void);
         int __ret_pu;                                           \
         __typeof__(*(ptr)) __pu_val;                            \
         __chk_user_ptr(ptr);                                    \
-        might_sleep();                                          \
-        if (current->mm)                                        \
-                might_lock_read(&current->mm->mmap_sem);        \
+        might_fault();                                          \
         __pu_val = x;                                           \
         switch (sizeof(*(ptr))) {                               \
         case 1:                                                 \
@@ -273,9 +267,7 @@ extern void __put_user_8(void);
 #define __put_user_size(x, ptr, size, retval, errret)                   \
 do {                                                                    \
         retval = 0;                                                     \
-        might_sleep();                                                  \
-        if (current->mm)                                                \
-                might_lock_read(&current->mm->mmap_sem);                \
+        might_fault();                                                  \
         __chk_user_ptr(ptr);                                            \
         switch (size) {                                                 \
         case 1:                                                         \
@@ -328,9 +320,7 @@ do {									\
 #define __get_user_size(x, ptr, size, retval, errret)                   \
 do {                                                                    \
         retval = 0;                                                     \
-        might_sleep();                                                  \
-        if (current->mm)                                                \
-                might_lock_read(&current->mm->mmap_sem);                \
+        might_fault();                                                  \
         __chk_user_ptr(ptr);                                            \
         switch (size) {                                                 \
         case 1:                                                         \