proc: somewhat simpler code for /proc/*/cmdline

"final" variable is OK but we can get away with less lines.

Link: http://lkml.kernel.org/r/20180221192751.GC28548@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 159abd0..4b27e26 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -318,8 +318,7 @@ static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
                        p = cmdline[i].p + pos1;
                        len = cmdline[i].len - pos1;
                        while (count > 0 && len > 0) {
-                               unsigned int nr_read, l;
-                               bool final;
+                               unsigned int nr_read, nr_write;
 
                                nr_read = min3(count, len, PAGE_SIZE);
                                nr_read = access_remote_vm(mm, p, page, nr_read, FOLL_ANON);
@@ -330,25 +329,20 @@ static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
                                 * Command line can be shorter than whole ARGV
                                 * even if last "marker" byte says it is not.
                                 */
-                               final = false;
-                               l = strnlen(page, nr_read);
-                               if (l < nr_read) {
-                                       nr_read = l;
-                                       final = true;
-                               }
+                               nr_write = strnlen(page, nr_read);
 
-                               if (copy_to_user(buf, page, nr_read)) {
+                               if (copy_to_user(buf, page, nr_write)) {
                                        rv = -EFAULT;
                                        goto out_free_page;
                                }
 
-                               p       += nr_read;
-                               len     -= nr_read;
-                               buf     += nr_read;
-                               count   -= nr_read;
-                               rv      += nr_read;
+                               p       += nr_write;
+                               len     -= nr_write;
+                               buf     += nr_write;
+                               count   -= nr_write;
+                               rv      += nr_write;
 
-                               if (final)
+                               if (nr_write < nr_read)
                                        goto out_free_page;
                        }