diff --git a/sys/cam/cam_xpt.c b/sys/cam/cam_xpt.c index c613c48560e5..d7667cb4e550 100644 --- a/sys/cam/cam_xpt.c +++ b/sys/cam/cam_xpt.c @@ -803,7 +803,8 @@ static void xpt_scanner_thread(void *dummy) { union ccb *ccb; - struct cam_path path; + struct mtx *mtx; + struct cam_ed *device; xpt_lock_buses(); for (;;) { @@ -815,15 +816,22 @@ xpt_scanner_thread(void *dummy) xpt_unlock_buses(); /* - * Since lock can be dropped inside and path freed - * by completion callback even before return here, - * take our own path copy for reference. + * We need to lock the device's mutex which we use as + * the path mutex. We can't do it directly because the + * cam_path in the ccb may wind up going away because + * the path lock may be dropped and the path retired in + * the completion callback. We do this directly to keep + * the reference counts in cam_path sane. We also have + * to copy the device pointer because ccb_h.path may + * be freed in the callback. */ - xpt_copy_path(&path, ccb->ccb_h.path); - xpt_path_lock(&path); + mtx = xpt_path_mtx(ccb->ccb_h.path); + device = ccb->ccb_h.path->device; + xpt_acquire_device(device); + mtx_lock(mtx); xpt_action(ccb); - xpt_path_unlock(&path); - xpt_release_path(&path); + mtx_unlock(mtx); + xpt_release_device(device); xpt_lock_buses(); } @@ -3686,15 +3694,6 @@ xpt_clone_path(struct cam_path **new_path_ptr, struct cam_path *path) new_path = (struct cam_path *)malloc(sizeof(*path), M_CAMPATH, M_NOWAIT); if (new_path == NULL) return(CAM_RESRC_UNAVAIL); - xpt_copy_path(new_path, path); - *new_path_ptr = new_path; - return (CAM_REQ_CMP); -} - -void -xpt_copy_path(struct cam_path *new_path, struct cam_path *path) -{ - *new_path = *path; if (path->bus != NULL) xpt_acquire_bus(path->bus); @@ -3702,6 +3701,8 @@ xpt_copy_path(struct cam_path *new_path, struct cam_path *path) xpt_acquire_target(path->target); if (path->device != NULL) xpt_acquire_device(path->device); + *new_path_ptr = new_path; + return (CAM_REQ_CMP); } void diff --git a/sys/cam/cam_xpt.h b/sys/cam/cam_xpt.h index 52af71fc44eb..250db1ea7448 100644 --- a/sys/cam/cam_xpt.h +++ b/sys/cam/cam_xpt.h @@ -140,8 +140,6 @@ cam_status xpt_compile_path(struct cam_path *new_path, lun_id_t lun_id); cam_status xpt_clone_path(struct cam_path **new_path, struct cam_path *path); -void xpt_copy_path(struct cam_path *new_path, - struct cam_path *path); void xpt_release_path(struct cam_path *path);