diff options
| -rw-r--r-- | drivers/s390/block/dasd_eckd.c | 73 |
1 files changed, 60 insertions, 13 deletions
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index ab84da5592e8..0483b2e76b11 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -82,6 +82,14 @@ static struct ccw_driver dasd_eckd_driver; /* see below */ #define INIT_CQR_UNFORMATTED 1 #define INIT_CQR_ERROR 2 +/* emergency request for reserve/release */ +static struct { + struct dasd_ccw_req cqr; + struct ccw1 ccw; + char data[32]; +} *dasd_reserve_req; +static DEFINE_MUTEX(dasd_reserve_mutex); + /* initial attempt at a probe function. this can be simplified once * the other detection code is gone */ @@ -2645,15 +2653,23 @@ dasd_eckd_release(struct dasd_device *device) struct dasd_ccw_req *cqr; int rc; struct ccw1 *ccw; + int useglobal; if (!capable(CAP_SYS_ADMIN)) return -EACCES; + useglobal = 0; cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device); if (IS_ERR(cqr)) { - DBF_DEV_EVENT(DBF_WARNING, device, "%s", - "Could not allocate initialization request"); - return PTR_ERR(cqr); + mutex_lock(&dasd_reserve_mutex); + useglobal = 1; + cqr = &dasd_reserve_req->cqr; + memset(cqr, 0, sizeof(*cqr)); + memset(&dasd_reserve_req->ccw, 0, + sizeof(dasd_reserve_req->ccw)); + cqr->cpaddr = &dasd_reserve_req->ccw; + cqr->data = &dasd_reserve_req->data; + cqr->magic = DASD_ECKD_MAGIC; } ccw = cqr->cpaddr; ccw->cmd_code = DASD_ECKD_CCW_RELEASE; @@ -2671,7 +2687,10 @@ dasd_eckd_release(struct dasd_device *device) rc = dasd_sleep_on_immediatly(cqr); - dasd_sfree_request(cqr, cqr->memdev); + if (useglobal) + mutex_unlock(&dasd_reserve_mutex); + else + dasd_sfree_request(cqr, cqr->memdev); return rc; } @@ -2687,15 +2706,23 @@ dasd_eckd_reserve(struct dasd_device *device) struct dasd_ccw_req *cqr; int rc; struct ccw1 *ccw; + int useglobal; if (!capable(CAP_SYS_ADMIN)) return -EACCES; + useglobal = 0; cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device); if (IS_ERR(cqr)) { - DBF_DEV_EVENT(DBF_WARNING, device, "%s", - "Could not allocate initialization request"); - return PTR_ERR(cqr); + mutex_lock(&dasd_reserve_mutex); + useglobal = 1; + cqr = &dasd_reserve_req->cqr; + memset(cqr, 0, sizeof(*cqr)); + memset(&dasd_reserve_req->ccw, 0, + sizeof(dasd_reserve_req->ccw)); + cqr->cpaddr = &dasd_reserve_req->ccw; + cqr->data = &dasd_reserve_req->data; + cqr->magic = DASD_ECKD_MAGIC; } ccw = cqr->cpaddr; ccw->cmd_code = DASD_ECKD_CCW_RESERVE; @@ -2713,7 +2740,10 @@ dasd_eckd_reserve(struct dasd_device *device) rc = dasd_sleep_on_immediatly(cqr); - dasd_sfree_request(cqr, cqr->memdev); + if (useglobal) + mutex_unlock(&dasd_reserve_mutex); + else + dasd_sfree_request(cqr, cqr->memdev); return rc; } @@ -2728,15 +2758,23 @@ dasd_eckd_steal_lock(struct dasd_device *device) struct dasd_ccw_req *cqr; int rc; struct ccw1 *ccw; + int useglobal; if (!capable(CAP_SYS_ADMIN)) return -EACCES; + useglobal = 0; cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device); if (IS_ERR(cqr)) { - DBF_DEV_EVENT(DBF_WARNING, device, "%s", - "Could not allocate initialization request"); - return PTR_ERR(cqr); + mutex_lock(&dasd_reserve_mutex); + useglobal = 1; + cqr = &dasd_reserve_req->cqr; + memset(cqr, 0, sizeof(*cqr)); + memset(&dasd_reserve_req->ccw, 0, + sizeof(dasd_reserve_req->ccw)); + cqr->cpaddr = &dasd_reserve_req->ccw; + cqr->data = &dasd_reserve_req->data; + cqr->magic = DASD_ECKD_MAGIC; } ccw = cqr->cpaddr; ccw->cmd_code = DASD_ECKD_CCW_SLCK; @@ -2754,7 +2792,10 @@ dasd_eckd_steal_lock(struct dasd_device *device) rc = dasd_sleep_on_immediatly(cqr); - dasd_sfree_request(cqr, cqr->memdev); + if (useglobal) + mutex_unlock(&dasd_reserve_mutex); + else + dasd_sfree_request(cqr, cqr->memdev); return rc; } @@ -3488,10 +3529,15 @@ dasd_eckd_init(void) int ret; ASCEBC(dasd_eckd_discipline.ebcname, 4); + dasd_reserve_req = kmalloc(sizeof(*dasd_reserve_req), + GFP_KERNEL | GFP_DMA); + if (!dasd_reserve_req) + return -ENOMEM; ret = ccw_driver_register(&dasd_eckd_driver); if (!ret) wait_for_device_probe(); - + else + kfree(dasd_reserve_req); return ret; } @@ -3499,6 +3545,7 @@ static void __exit dasd_eckd_cleanup(void) { ccw_driver_unregister(&dasd_eckd_driver); + kfree(dasd_reserve_req); } module_init(dasd_eckd_init); |