fs/proc/vmcore.c: put if tests in the top of the while loop to reduce duplication

In read_vmcore() two `if' tests are duplicated.  Change the position of
them could reduce the duplication.  This change does not affect the
behaviour of the function.

[akpm@linux-foundation.org: avoid `if (foo = bar)' thing, use min_t()]
[akpm@linux-foundation.org: s/max_t/min_t/]
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 13 deletions

diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 41dd018f72dd..b870f740ab5a 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -176,15 +176,15 @@ static ssize_t read_vmcore(struct file *file, char __user *buffer,
         start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m);
         if (!curr_m)
                 return -EINVAL;
-        if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
-                tsz = buflen;
-
-        /* Calculate left bytes in current memory segment. */
-        nr_bytes = (curr_m->size - (start - curr_m->paddr));
-        if (tsz > nr_bytes)
-                tsz = nr_bytes;
 
         while (buflen) {
+                tsz = min_t(size_t, buflen, PAGE_SIZE - (start & ~PAGE_MASK));
+
+                /* Calculate left bytes in current memory segment. */
+                nr_bytes = (curr_m->size - (start - curr_m->paddr));
+                if (tsz > nr_bytes)
+                        tsz = nr_bytes;
+
                 tmp = read_from_oldmem(buffer, tsz, &start, 1);
                 if (tmp < 0)
                         return tmp;
@@ -199,12 +199,6 @@ static ssize_t read_vmcore(struct file *file, char __user *buffer,
                                                 struct vmcore, list);
                         start = curr_m->paddr;
                 }
-                if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
-                        tsz = buflen;
-                /* Calculate left bytes in current memory segment. */
-                nr_bytes = (curr_m->size - (start - curr_m->paddr));
-                if (tsz > nr_bytes)
-                        tsz = nr_bytes;
         }
         return acc;
 }