kexec: Use min() and min_t() to simplify logic

Simplify the logic of variable assignments.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/kernel/kexec.c b/kernel/kexec.c
index e1e5ce9bf53edcc55f00c0eae29496ba949568e5..97096351de18f0eb0b69f2bc3f2d1f6376172c4a 100644 (file)
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -819,13 +819,9 @@ static int kimage_load_normal_segment(struct kimage *image,
                /* Start with a clear page */
                clear_page(ptr);
                ptr += maddr & ~PAGE_MASK;
-               mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK);
-               if (mchunk > mbytes)
-                       mchunk = mbytes;
-
-               uchunk = mchunk;
-               if (uchunk > ubytes)
-                       uchunk = ubytes;
+               mchunk = min_t(size_t, mbytes,
+                              (size_t)(PAGE_SIZE - (maddr & ~PAGE_MASK)));
+               uchunk = min_t(size_t, ubytes, mchunk);
 
                result = copy_from_user(ptr, buf, uchunk);
                kunmap(page);
@@ -871,13 +867,10 @@ static int kimage_load_crash_segment(struct kimage *image,
                }
                ptr = kmap(page);
                ptr += maddr & ~PAGE_MASK;
-               mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK);
-               if (mchunk > mbytes)
-                       mchunk = mbytes;
-
-               uchunk = mchunk;
-               if (uchunk > ubytes) {
-                       uchunk = ubytes;
+               mchunk = min_t(size_t, mbytes,
+                              (size_t)(PAGE_SIZE - (maddr & ~PAGE_MASK)));
+               uchunk = min_t(size_t, ubytes, mchunk);
+               if (mchunk > uchunk) {
                        /* Zero the trailing part of the page */
                        memset(ptr + uchunk, 0, mchunk - uchunk);
                }
@@ -1454,8 +1447,7 @@ void vmcoreinfo_append_str(const char *fmt, ...)
        r = vsnprintf(buf, sizeof(buf), fmt, args);
        va_end(args);
 
-       if (r + vmcoreinfo_size > vmcoreinfo_max_size)
-               r = vmcoreinfo_max_size - vmcoreinfo_size;
+       r = min_t(size_t, r, vmcoreinfo_max_size - vmcoreinfo_size);
 
        memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);