convert do_select()

take the logics from fdget() to fdput() into an inlined helper - with existing
wait_key_set() subsumed into that.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/select.c b/fs/select.c
index a77907faf2b459d9a2005575d1fd1befa4c06e5b..b41e2d651cc1b519c263077a84fec0dc7a736479 100644 (file)
--- a/fs/select.c
+++ b/fs/select.c
@@ -462,15 +462,22 @@ get_max:
                         EPOLLNVAL)
 #define POLLEX_SET (EPOLLPRI | EPOLLNVAL)
 
-static inline void wait_key_set(poll_table *wait, unsigned long in,
+static inline __poll_t select_poll_one(int fd, poll_table *wait, unsigned long in,
                                unsigned long out, unsigned long bit,
                                __poll_t ll_flag)
 {
+       CLASS(fd, f)(fd);
+
+       if (fd_empty(f))
+               return EPOLLNVAL;
+
        wait->_key = POLLEX_SET | ll_flag;
        if (in & bit)
                wait->_key |= POLLIN_SET;
        if (out & bit)
                wait->_key |= POLLOUT_SET;
+
+       return vfs_poll(fd_file(f), wait);
 }
 
 static noinline_for_stack int do_select(int n, fd_set_bits *fds, struct timespec64 *end_time)
@@ -522,20 +529,12 @@ static noinline_for_stack int do_select(int n, fd_set_bits *fds, struct timespec
                        }
 
                        for (j = 0; j < BITS_PER_LONG; ++j, ++i, bit <<= 1) {
-                               struct fd f;
                                if (i >= n)
                                        break;
                                if (!(bit & all_bits))
                                        continue;
-                               mask = EPOLLNVAL;
-                               f = fdget(i);
-                               if (fd_file(f)) {
-                                       wait_key_set(wait, in, out, bit,
-                                                    busy_flag);
-                                       mask = vfs_poll(fd_file(f), wait);
-
-                                       fdput(f);
-                               }
+                               mask = select_poll_one(i, wait, in, out, bit,
+                                                      busy_flag);
                                if ((mask & POLLIN_SET) && (in & bit)) {
                                        res_in |= bit;
                                        retval++;