futex: Consistently use fshared as boolean

Since fshared is only conveying true/false values, declare it as bool.

In get_futex_key() the usage of fshared can be restricted to the first part
of the function. If fshared is false the function is terminated early and
the subsequent code can use a constant 'true' instead of the variable.

Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200702202843.520764-5-andrealmeid@collabora.com

diff --git a/kernel/futex.c b/kernel/futex.c
index 362fbca..cda9175 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -476,7 +476,7 @@ static u64 get_inode_sequence_number(struct inode *inode)
 /**
  * get_futex_key() - Get parameters which are the keys for a futex
  * @uaddr:     virtual address of the futex
- * @fshared:   0 for a PROCESS_PRIVATE futex, 1 for PROCESS_SHARED
+ * @fshared:   false for a PROCESS_PRIVATE futex, true for PROCESS_SHARED
  * @key:       address where result is stored.
  * @rw:                mapping needs to be read/write (values: FUTEX_READ,
  *              FUTEX_WRITE)
@@ -500,8 +500,8 @@ static u64 get_inode_sequence_number(struct inode *inode)
  *
  * lock_page() might sleep, the caller should not hold a spinlock.
  */
-static int
-get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key, enum futex_access rw)
+static int get_futex_key(u32 __user *uaddr, bool fshared, union futex_key *key,
+                        enum futex_access rw)
 {
        unsigned long address = (unsigned long)uaddr;
        struct mm_struct *mm = current->mm;
@@ -538,7 +538,7 @@ get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key, enum futex_a
 
 again:
        /* Ignore any VERIFY_READ mapping (futex common case) */
-       if (unlikely(should_fail_futex(fshared)))
+       if (unlikely(should_fail_futex(true)))
                return -EFAULT;
 
        err = get_user_pages_fast(address, 1, FOLL_WRITE, &page);
@@ -626,7 +626,7 @@ again:
                 * A RO anonymous page will never change and thus doesn't make
                 * sense for futex operations.
                 */
-               if (unlikely(should_fail_futex(fshared)) || ro) {
+               if (unlikely(should_fail_futex(true)) || ro) {
                        err = -EFAULT;
                        goto out;
                }