/*===========================================================================* * blockdriver_handle_request * *===========================================================================*/ int blockdriver_handle_request(struct blockdriver *bdp, message *m_ptr, thread_id_t id) { /* Call the appropiate driver function, based on the type of request. Return * the result code that is to be sent back to the caller, or EDONTREPLY if no * reply is to be sent. */ int r; /* We might get spurious requests if the driver has been restarted. Deny any * requests on devices that have not previously been opened, signaling the * caller that something went wrong. */ if (IS_BDEV_RQ(m_ptr->m_type) && !is_open_dev(m_ptr->BDEV_MINOR)) { /* Reply ERESTART to spurious requests for unopened devices. */ if (m_ptr->m_type != BDEV_OPEN) return ERESTART; /* Mark the device as opened otherwise. */ set_open_dev(m_ptr->BDEV_MINOR); } trace_start(id, m_ptr); /* Call the appropriate function(s) for this request. */ switch (m_ptr->m_type) { case BDEV_OPEN: r = do_open(bdp, m_ptr); break; case BDEV_CLOSE: r = do_close(bdp, m_ptr); break; case BDEV_READ: case BDEV_WRITE: r = do_rdwt(bdp, m_ptr); break; case BDEV_GATHER: case BDEV_SCATTER: r = do_vrdwt(bdp, m_ptr, id); break; case BDEV_IOCTL: r = do_ioctl(bdp, m_ptr); break; default: if (bdp->bdr_other) r = bdp->bdr_other(m_ptr); else r = EINVAL; } /* Let the driver perform any cleanup. */ if (bdp->bdr_cleanup != NULL) (*bdp->bdr_cleanup)(); trace_finish(id, r); return r; }
/*===========================================================================* * main * *===========================================================================*/ int main(void) { message msg; int r, ipc_status; /* SEF local startup. */ sef_local_startup(); /* The receive loop. */ for (;;) { if ((r = driver_receive(ANY, &msg, &ipc_status)) != OK) panic("memory: driver_receive failed (%d)", r); if (IS_BDEV_RQ(msg.m_type)) blockdriver_process(&m_bdtab, &msg, ipc_status); else chardriver_process(&m_cdtab, CHARDRIVER_SYNC, &msg, ipc_status); } return(OK); }
/*===========================================================================* * blockdriver_process_on_thread * *===========================================================================*/ void blockdriver_process_on_thread(struct blockdriver *bdp, message *m_ptr, int ipc_status, thread_id_t id) { /* Call the appropiate driver function, based on the type of request. Send * a result code to the caller. The call is processed in the context of the * given thread ID, which may be SINGLE_THREAD for single-threaded callers. */ int r; /* Check for notifications first. We never reply to notifications. */ if (is_ipc_notify(ipc_status)) { switch (_ENDPOINT_P(m_ptr->m_source)) { case HARDWARE: if (bdp->bdr_intr) (*bdp->bdr_intr)(m_ptr->m_notify.interrupts); break; case CLOCK: if (bdp->bdr_alarm) (*bdp->bdr_alarm)(m_ptr->m_notify.timestamp); break; default: if (bdp->bdr_other) (*bdp->bdr_other)(m_ptr, ipc_status); } return; /* do not send a reply */ } /* Reply to character driver open requests with an error code. Otherwise, if * someone creates a character device node for a block driver, opening that * device node will cause the corresponding VFS thread to block forever. */ if (m_ptr->m_type == CDEV_OPEN) { do_char_open(m_ptr, ipc_status); return; } /* We might get spurious requests if the driver has been restarted. Deny any * requests on devices that have not previously been opened, signaling the * caller that something went wrong. */ if (IS_BDEV_RQ(m_ptr->m_type) && !is_open_dev(m_ptr->m_lbdev_lblockdriver_msg.minor)) { /* Reply ERESTART to spurious requests for unopened devices. */ if (m_ptr->m_type != BDEV_OPEN) { blockdriver_reply(m_ptr, ipc_status, ERESTART); return; } /* Mark the device as opened otherwise. */ set_open_dev(m_ptr->m_lbdev_lblockdriver_msg.minor); } trace_start(id, m_ptr); /* Call the appropriate function(s) for this request. */ switch (m_ptr->m_type) { case BDEV_OPEN: r = do_open(bdp, m_ptr); break; case BDEV_CLOSE: r = do_close(bdp, m_ptr); break; case BDEV_READ: case BDEV_WRITE: r = do_rdwt(bdp, m_ptr); break; case BDEV_GATHER: case BDEV_SCATTER: r = do_vrdwt(bdp, m_ptr, id); break; case BDEV_IOCTL: r = do_ioctl(bdp, m_ptr); break; default: if (bdp->bdr_other != NULL) (*bdp->bdr_other)(m_ptr, ipc_status); return; /* do not send a reply */ } /* Let the driver perform any cleanup. */ if (bdp->bdr_cleanup != NULL) (*bdp->bdr_cleanup)(); trace_finish(id, r); blockdriver_reply(m_ptr, ipc_status, r); }