From 2cd0b70c55b0e71f578134510107d002d52ee235 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sun, 14 Oct 2018 13:20:48 -0600 Subject: [PATCH] cdrom: don't attempt to fiddle with cdo->capability [ Upstream commit 8f94004e2a51a3ea195cf3447eb5d5906f36d8b3 ] We can't modify cdo->capability as it is defined as a const. Change the modification hack to just WARN_ON_ONCE() if we hit any of the invalid combinations. This fixes a regression for pcd, which doesn't work after the constify patch. Fixes: 853fe1bf7554 ("cdrom: Make device operations read-only") Tested-by: Ondrej Zary Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/cdrom/cdrom.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index 27a82a5..933268b 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -411,10 +411,10 @@ static int cdrom_get_disc_info(struct cdrom_device_info *cdi, * hack to have the capability flags defined const, while we can still * change it here without gcc complaining at every line. */ -#define ENSURE(call, bits) \ -do { \ - if (cdo->call == NULL) \ - *change_capability &= ~(bits); \ +#define ENSURE(cdo, call, bits) \ +do { \ + if (cdo->call == NULL) \ + WARN_ON_ONCE((cdo)->capability & (bits)); \ } while (0) /* @@ -590,7 +590,6 @@ int register_cdrom(struct cdrom_device_info *cdi) { static char banner_printed; const struct cdrom_device_ops *cdo = cdi->ops; - int *change_capability = (int *)&cdo->capability; /* hack */ cd_dbg(CD_OPEN, "entering register_cdrom\n"); @@ -602,16 +601,16 @@ int register_cdrom(struct cdrom_device_info *cdi) cdrom_sysctl_register(); } - ENSURE(drive_status, CDC_DRIVE_STATUS); + ENSURE(cdo, drive_status, CDC_DRIVE_STATUS); if (cdo->check_events == NULL && cdo->media_changed == NULL) - *change_capability = ~(CDC_MEDIA_CHANGED | CDC_SELECT_DISC); - ENSURE(tray_move, CDC_CLOSE_TRAY | CDC_OPEN_TRAY); - ENSURE(lock_door, CDC_LOCK); - ENSURE(select_speed, CDC_SELECT_SPEED); - ENSURE(get_last_session, CDC_MULTI_SESSION); - ENSURE(get_mcn, CDC_MCN); - ENSURE(reset, CDC_RESET); - ENSURE(generic_packet, CDC_GENERIC_PACKET); + WARN_ON_ONCE(cdo->capability & (CDC_MEDIA_CHANGED | CDC_SELECT_DISC)); + ENSURE(cdo, tray_move, CDC_CLOSE_TRAY | CDC_OPEN_TRAY); + ENSURE(cdo, lock_door, CDC_LOCK); + ENSURE(cdo, select_speed, CDC_SELECT_SPEED); + ENSURE(cdo, get_last_session, CDC_MULTI_SESSION); + ENSURE(cdo, get_mcn, CDC_MCN); + ENSURE(cdo, reset, CDC_RESET); + ENSURE(cdo, generic_packet, CDC_GENERIC_PACKET); cdi->mc_flags = 0; cdi->options = CDO_USE_FFLAGS; -- 2.7.4