From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52576) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YuXcw-0003JB-6Y for qemu-devel@nongnu.org; Mon, 18 May 2015 22:51:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YuXcv-0001Ux-72 for qemu-devel@nongnu.org; Mon, 18 May 2015 22:51:30 -0400 From: Fam Zheng Date: Tue, 19 May 2015 10:50:59 +0000 Message-Id: <1432032670-15124-3-git-send-email-famz@redhat.com> In-Reply-To: <1432032670-15124-1-git-send-email-famz@redhat.com> References: <1432032670-15124-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH v3 02/13] qemu-nbd: Switch to qemu_set_fd_handler List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , qemu-block@nongnu.org, Juan Quintela , Jason Wang , Vincenzo Maffione , "Vassili Karpov (malc)" , Gerd Hoffmann , Stefan Hajnoczi , Amit Shah , Paolo Bonzini , Giuseppe Lettieri , Luigi Rizzo Achieved by: - Remembering the server fd with a global variable, in order to access it from nbd_client_closed. - Checking nbd_can_accept() and updating server_fd handler whenever client connects or disconnects. Signed-off-by: Fam Zheng Reviewed-by: Paolo Bonzini --- qemu-nbd.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/qemu-nbd.c b/qemu-nbd.c index 7e690ff..5af6d11 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -53,6 +53,7 @@ static int persistent = 0; static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state; static int shared = 1; static int nb_fds; +static int server_fd; static void usage(const char *name) { @@ -340,7 +341,7 @@ out: return (void *) EXIT_FAILURE; } -static int nbd_can_accept(void *opaque) +static int nbd_can_accept(void) { return nb_fds < shared; } @@ -351,19 +352,21 @@ static void nbd_export_closed(NBDExport *exp) state = TERMINATED; } +static void nbd_update_server_fd_handler(int fd); + static void nbd_client_closed(NBDClient *client) { nb_fds--; if (nb_fds == 0 && !persistent && state == RUNNING) { state = TERMINATE; } + nbd_update_server_fd_handler(server_fd); qemu_notify_event(); nbd_client_put(client); } static void nbd_accept(void *opaque) { - int server_fd = (uintptr_t) opaque; struct sockaddr_in addr; socklen_t addr_len = sizeof(addr); @@ -380,12 +383,22 @@ static void nbd_accept(void *opaque) if (nbd_client_new(exp, fd, nbd_client_closed)) { nb_fds++; + nbd_update_server_fd_handler(server_fd); } else { shutdown(fd, 2); close(fd); } } +static void nbd_update_server_fd_handler(int fd) +{ + if (nbd_can_accept()) { + qemu_set_fd_handler(fd, nbd_accept, NULL, (void *)(uintptr_t)fd); + } else { + qemu_set_fd_handler(fd, NULL, NULL, NULL); + } +} + int main(int argc, char **argv) { BlockBackend *blk; @@ -761,8 +774,8 @@ int main(int argc, char **argv) memset(&client_thread, 0, sizeof(client_thread)); } - qemu_set_fd_handler2(fd, nbd_can_accept, nbd_accept, NULL, - (void *)(uintptr_t)fd); + server_fd = fd; + nbd_update_server_fd_handler(fd); /* now when the initialization is (almost) complete, chdir("/") * to free any busy filesystems */ -- 2.4.1