util/userfaultfd: Remove unused uffd_poll_events

uffd_poll_events has been unused since it was added; it's also
just a wrapper around a plain old poll call, so doesn't add anything.

Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240919134626.166183-8-dave@treblig.org
Signed-off-by: Peter Xu <peterx@redhat.com>

include/qemu/userfaultfd.h

@@ -39,7 +39,6 @@ int uffd_copy_page(int uffd_fd, void *dst_addr, void *src_addr,
 int uffd_zero_page(int uffd_fd, void *addr, uint64_t length, bool dont_wake);
 int uffd_wakeup(int uffd_fd, void *addr, uint64_t length);
 int uffd_read_events(int uffd_fd, struct uffd_msg *msgs, int count);
-bool uffd_poll_events(int uffd_fd, int tmo);
 
 #endif /* CONFIG_LINUX */
 

util/userfaultfd.c

@@ -358,31 +358,3 @@ int uffd_read_events(int uffd_fd, struct uffd_msg *msgs, int count)
 
     return (int) (res / sizeof(struct uffd_msg));
 }
-
-/**
- * uffd_poll_events: poll UFFD file descriptor for read
- *
- * Returns true if events are available for read, false otherwise
- *
- * @uffd_fd: UFFD file descriptor
- * @tmo: timeout value
- */
-bool uffd_poll_events(int uffd_fd, int tmo)
-{
-    int res;
-    struct pollfd poll_fd = { .fd = uffd_fd, .events = POLLIN, .revents = 0 };
-
-    do {
-        res = poll(&poll_fd, 1, tmo);
-    } while (res < 0 && errno == EINTR);
-
-    if (res == 0) {
-        return false;
-    }
-    if (res < 0) {
-        error_report("uffd_poll_events() failed: errno=%i", errno);
-        return false;
-    }
-
-    return (poll_fd.revents & POLLIN) != 0;
-}