1 files changed, 221 insertions, 40 deletions

diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index 549443af121c..a1ebf5722ae5 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -90,6 +90,18 @@ static struct {
 } *dasd_reserve_req;
 static DEFINE_MUTEX(dasd_reserve_mutex);
 
+/* definitions for the path verification worker */
+struct path_verification_work_data {
+        struct work_struct worker;
+        struct dasd_device *device;
+        struct dasd_ccw_req cqr;
+        struct ccw1 ccw;
+        __u8 rcd_buffer[DASD_ECKD_RCD_DATA_SIZE];
+        int isglobal;
+        __u8 tbvpm;
+};
+static struct path_verification_work_data *path_verification_worker;
+static DEFINE_MUTEX(dasd_path_verification_mutex);
 
 /* initial attempt at a probe function. this can be simplified once
  * the other detection code is gone */
@@ -755,26 +767,27 @@ static int dasd_eckd_get_uid(struct dasd_device *device, struct dasd_uid *uid)
         return -EINVAL;
 }
 
-static struct dasd_ccw_req *dasd_eckd_build_rcd_lpm(struct dasd_device *device,
-                                                    void *rcd_buffer,
-                                                    struct ciw *ciw, __u8 lpm)
+static void dasd_eckd_fill_rcd_cqr(struct dasd_device *device,
+                                   struct dasd_ccw_req *cqr,
+                                   __u8 *rcd_buffer,
+                                   __u8 lpm)
 {
-        struct dasd_ccw_req *cqr;
         struct ccw1 *ccw;
-
-        cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* RCD */, ciw->count,
-                                   device);
-
-        if (IS_ERR(cqr)) {
-                DBF_DEV_EVENT(DBF_WARNING, device, "%s",
-                              "Could not allocate RCD request");
-                return cqr;
-        }
+        /*
+         * buffer has to start with EBCDIC "V1.0" to show
+         * support for virtual device SNEQ
+         */
+        rcd_buffer[0] = 0xE5;
+        rcd_buffer[1] = 0xF1;
+        rcd_buffer[2] = 0x4B;
+        rcd_buffer[3] = 0xF0;
 
         ccw = cqr->cpaddr;
-        ccw->cmd_code = ciw->cmd;
+        ccw->cmd_code = DASD_ECKD_CCW_RCD;
+        ccw->flags = 0;
         ccw->cda = (__u32)(addr_t)rcd_buffer;
-        ccw->count = ciw->count;
+        ccw->count = DASD_ECKD_RCD_DATA_SIZE;
+        cqr->magic = DASD_ECKD_MAGIC;
 
         cqr->startdev = device;
         cqr->memdev = device;
@@ -784,7 +797,29 @@ static struct dasd_ccw_req *dasd_eckd_build_rcd_lpm(struct dasd_device *device,
         cqr->retries = 256;
         cqr->buildclk = get_clock();
         cqr->status = DASD_CQR_FILLED;
-        return cqr;
+        set_bit(DASD_CQR_VERIFY_PATH, &cqr->flags);
+}
+
+static int dasd_eckd_read_conf_immediately(struct dasd_device *device,
+                                           struct dasd_ccw_req *cqr,
+                                           __u8 *rcd_buffer,
+                                           __u8 lpm)
+{
+        struct ciw *ciw;
+        int rc;
+        /*
+         * sanity check: scan for RCD command in extended SenseID data
+         * some devices do not support RCD
+         */
+        ciw = ccw_device_get_ciw(device->cdev, CIW_TYPE_RCD);
+        if (!ciw || ciw->cmd != DASD_ECKD_CCW_RCD)
+                return -EOPNOTSUPP;
+
+        dasd_eckd_fill_rcd_cqr(device, cqr, rcd_buffer, lpm);
+        clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
+        cqr->retries = 5;
+        rc = dasd_sleep_on_immediatly(cqr);
+        return rc;
 }
 
 static int dasd_eckd_read_conf_lpm(struct dasd_device *device,
@@ -797,32 +832,29 @@ static int dasd_eckd_read_conf_lpm(struct dasd_device *device,
         struct dasd_ccw_req *cqr;
 
         /*
-         * scan for RCD command in extended SenseID data
+         * sanity check: scan for RCD command in extended SenseID data
+         * some devices do not support RCD
          */
         ciw = ccw_device_get_ciw(device->cdev, CIW_TYPE_RCD);
-        if (!ciw || ciw->cmd == 0) {
+        if (!ciw || ciw->cmd != DASD_ECKD_CCW_RCD) {
                 ret = -EOPNOTSUPP;
                 goto out_error;
         }
-        rcd_buf = kzalloc(ciw->count, GFP_KERNEL | GFP_DMA);
+        rcd_buf = kzalloc(DASD_ECKD_RCD_DATA_SIZE, GFP_KERNEL | GFP_DMA);
         if (!rcd_buf) {
                 ret = -ENOMEM;
                 goto out_error;
         }
-
-        /*
-         * buffer has to start with EBCDIC "V1.0" to show
-         * support for virtual device SNEQ
-         */
-        rcd_buf[0] = 0xE5;
-        rcd_buf[1] = 0xF1;
-        rcd_buf[2] = 0x4B;
-        rcd_buf[3] = 0xF0;
-        cqr = dasd_eckd_build_rcd_lpm(device, rcd_buf, ciw, lpm);
+        cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1 /* RCD */,
+                                   0, /* use rcd_buf as data ara */
+                                   device);
         if (IS_ERR(cqr)) {
-                ret =  PTR_ERR(cqr);
+                DBF_DEV_EVENT(DBF_WARNING, device, "%s",
+                              "Could not allocate RCD request");
+                ret = -ENOMEM;
                 goto out_error;
         }
+        dasd_eckd_fill_rcd_cqr(device, cqr, rcd_buf, lpm);
         ret = dasd_sleep_on(cqr);
         /*
          * on success we update the user input parms
@@ -831,7 +863,7 @@ static int dasd_eckd_read_conf_lpm(struct dasd_device *device,
         if (ret)
                 goto out_error;
 
-        *rcd_buffer_size = ciw->count;
+        *rcd_buffer_size = DASD_ECKD_RCD_DATA_SIZE;
         *rcd_buffer = rcd_buf;
         return 0;
 out_error:
@@ -901,18 +933,18 @@ static int dasd_eckd_read_conf(struct dasd_device *device)
         void *conf_data;
         int conf_len, conf_data_saved;
         int rc;
-        __u8 lpm;
+        __u8 lpm, opm;
         struct dasd_eckd_private *private;
-        struct dasd_eckd_path *path_data;
+        struct dasd_path *path_data;
 
         private = (struct dasd_eckd_private *) device->private;
-        path_data = (struct dasd_eckd_path *) &private->path_data;
-        path_data->opm = ccw_device_get_path_mask(device->cdev);
+        path_data = &device->path_data;
+        opm = ccw_device_get_path_mask(device->cdev);
         lpm = 0x80;
         conf_data_saved = 0;
         /* get configuration data per operational path */
         for (lpm = 0x80; lpm; lpm>>= 1) {
-                if (lpm & path_data->opm){
+                if (lpm & opm) {
                         rc = dasd_eckd_read_conf_lpm(device, &conf_data,
                                                      &conf_len, lpm);
                         if (rc && rc != -EOPNOTSUPP) {  /* -EOPNOTSUPP is ok */
@@ -925,6 +957,8 @@ static int dasd_eckd_read_conf(struct dasd_device *device)
                                 DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
                                                 "No configuration data "
                                                 "retrieved");
+                                /* no further analysis possible */
+                                path_data->opm |= lpm;
                                 continue;       /* no error */
                         }
                         /* save first valid configuration data */
@@ -948,6 +982,7 @@ static int dasd_eckd_read_conf(struct dasd_device *device)
                                 path_data->ppm |= lpm;
                                 break;
                         }
+                        path_data->opm |= lpm;
                         if (conf_data != private->conf_data)
                                 kfree(conf_data);
                 }
@@ -955,6 +990,140 @@ static int dasd_eckd_read_conf(struct dasd_device *device)
         return 0;
 }
 
+static int verify_fcx_max_data(struct dasd_device *device, __u8 lpm)
+{
+        struct dasd_eckd_private *private;
+        int mdc;
+        u32 fcx_max_data;
+
+        private = (struct dasd_eckd_private *) device->private;
+        if (private->fcx_max_data) {
+                mdc = ccw_device_get_mdc(device->cdev, lpm);
+                if ((mdc < 0)) {
+                        dev_warn(&device->cdev->dev,
+                                 "Detecting the maximum data size for zHPF "
+                                 "requests failed (rc=%d) for a new path %x\n",
+                                 mdc, lpm);
+                        return mdc;
+                }
+                fcx_max_data = mdc * FCX_MAX_DATA_FACTOR;
+                if (fcx_max_data < private->fcx_max_data) {
+                        dev_warn(&device->cdev->dev,
+                                 "The maximum data size for zHPF requests %u "
+                                 "on a new path %x is below the active maximum "
+                                 "%u\n", fcx_max_data, lpm,
+                                 private->fcx_max_data);
+                        return -EACCES;
+                }
+        }
+        return 0;
+}
+
+static void do_path_verification_work(struct work_struct *work)
+{
+        struct path_verification_work_data *data;
+        struct dasd_device *device;
+        __u8 lpm, opm, npm, ppm, epm;
+        unsigned long flags;
+        int rc;
+
+        data = container_of(work, struct path_verification_work_data, worker);
+        device = data->device;
+
+        opm = 0;
+        npm = 0;
+        ppm = 0;
+        epm = 0;
+        for (lpm = 0x80; lpm; lpm >>= 1) {
+                if (lpm & data->tbvpm) {
+                        memset(data->rcd_buffer, 0, sizeof(data->rcd_buffer));
+                        memset(&data->cqr, 0, sizeof(data->cqr));
+                        data->cqr.cpaddr = &data->ccw;
+                        rc = dasd_eckd_read_conf_immediately(device, &data->cqr,
+                                                             data->rcd_buffer,
+                                                             lpm);
+                        if (!rc) {
+                                switch (dasd_eckd_path_access(data->rcd_buffer,
+                                                     DASD_ECKD_RCD_DATA_SIZE)) {
+                                case 0x02:
+                                        npm |= lpm;
+                                        break;
+                                case 0x03:
+                                        ppm |= lpm;
+                                        break;
+                                }
+                                opm |= lpm;
+                        } else if (rc == -EOPNOTSUPP) {
+                                DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+                                       "path verification: No configuration "
+                                       "data retrieved");
+                                opm |= lpm;
+                        } else if (rc == -EAGAIN) {
+                                DBF_EVENT_DEVID(DBF_WARNING, device->cdev, "%s",
+                                        "path verification: device is stopped,"
+                                        " try again later");
+                                epm |= lpm;
+                        } else {
+                                dev_warn(&device->cdev->dev,
+                                         "Reading device feature codes failed "
+                                         "(rc=%d) for new path %x\n", rc, lpm);
+                                continue;
+                        }
+                        if (verify_fcx_max_data(device, lpm)) {
+                                opm &= ~lpm;
+                                npm &= ~lpm;
+                                ppm &= ~lpm;
+                        }
+                }
+        }
+        /*
+         * There is a small chance that a path is lost again between
+         * above path verification and the following modification of
+         * the device opm mask. We could avoid that race here by using
+         * yet another path mask, but we rather deal with this unlikely
+         * situation in dasd_start_IO.
+         */
+        spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
+        if (!device->path_data.opm && opm) {
+                device->path_data.opm = opm;
+                dasd_generic_path_operational(device);
+        } else
+                device->path_data.opm |= opm;
+        device->path_data.npm |= npm;
+        device->path_data.ppm |= ppm;
+        device->path_data.tbvpm |= epm;
+        spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
+
+        dasd_put_device(device);
+        if (data->isglobal)
+                mutex_unlock(&dasd_path_verification_mutex);
+        else
+                kfree(data);
+}
+
+static int dasd_eckd_verify_path(struct dasd_device *device, __u8 lpm)
+{
+        struct path_verification_work_data *data;
+
+        data = kmalloc(sizeof(*data), GFP_ATOMIC | GFP_DMA);
+        if (!data) {
+                if (mutex_trylock(&dasd_path_verification_mutex)) {
+                        data = path_verification_worker;
+                        data->isglobal = 1;
+                } else
+                        return -ENOMEM;
+        } else {
+                memset(data, 0, sizeof(*data));
+                data->isglobal = 0;
+        }
+        INIT_WORK(&data->worker, do_path_verification_work);
+        dasd_get_device(device);
+        data->device = device;
+        data->tbvpm = lpm;
+        schedule_work(&data->worker);
+        return 0;
+}
+
 static int dasd_eckd_read_features(struct dasd_device *device)
 {
         struct dasd_psf_prssd_data *prssdp;
@@ -1749,6 +1918,7 @@ static void dasd_eckd_handle_terminated_request(struct dasd_ccw_req *cqr)
         if (cqr->block && (cqr->startdev != cqr->block->base)) {
                 dasd_eckd_reset_ccw_to_base_io(cqr);
                 cqr->startdev = cqr->block->base;
+                cqr->lpm = cqr->block->base->path_data.opm;
         }
 };
 
@@ -2017,7 +2187,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_single(
         cqr->memdev = startdev;
         cqr->block = block;
         cqr->expires = startdev->default_expires * HZ;  /* default 5 minutes */
-        cqr->lpm = private->path_data.ppm;
+        cqr->lpm = startdev->path_data.ppm;
         cqr->retries = 256;
         cqr->buildclk = get_clock();
         cqr->status = DASD_CQR_FILLED;
@@ -2194,7 +2364,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_track(
         cqr->memdev = startdev;
         cqr->block = block;
         cqr->expires = startdev->default_expires * HZ;  /* default 5 minutes */
-        cqr->lpm = private->path_data.ppm;
+        cqr->lpm = startdev->path_data.ppm;
         cqr->retries = 256;
         cqr->buildclk = get_clock();
         cqr->status = DASD_CQR_FILLED;
@@ -2484,7 +2654,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_tpm_track(
         cqr->memdev = startdev;
         cqr->block = block;
         cqr->expires = startdev->default_expires * HZ;  /* default 5 minutes */
-        cqr->lpm = private->path_data.ppm;
+        cqr->lpm = startdev->path_data.ppm;
         cqr->retries = 256;
         cqr->buildclk = get_clock();
         cqr->status = DASD_CQR_FILLED;
@@ -3624,6 +3794,7 @@ static struct ccw_driver dasd_eckd_driver = {
         .set_offline = dasd_generic_set_offline,
         .set_online  = dasd_eckd_set_online,
         .notify      = dasd_generic_notify,
+        .path_event  = dasd_generic_path_event,
         .freeze      = dasd_generic_pm_freeze,
         .thaw        = dasd_generic_restore_device,
         .restore     = dasd_generic_restore_device,
@@ -3651,6 +3822,7 @@ static struct dasd_discipline dasd_eckd_discipline = {
         .check_device = dasd_eckd_check_characteristics,
         .uncheck_device = dasd_eckd_uncheck_device,
         .do_analysis = dasd_eckd_do_analysis,
+        .verify_path = dasd_eckd_verify_path,
         .ready_to_online = dasd_eckd_ready_to_online,
         .online_to_ready = dasd_eckd_online_to_ready,
         .fill_geometry = dasd_eckd_fill_geometry,
@@ -3683,11 +3855,19 @@ dasd_eckd_init(void)
                                    GFP_KERNEL | GFP_DMA);
         if (!dasd_reserve_req)
                 return -ENOMEM;
+        path_verification_worker = kmalloc(sizeof(*path_verification_worker),
+                                   GFP_KERNEL | GFP_DMA);
+        if (!path_verification_worker) {
+                kfree(dasd_reserve_req);
+                return -ENOMEM;
+        }
         ret = ccw_driver_register(&dasd_eckd_driver);
         if (!ret)
                 wait_for_device_probe();
-        else
+        else {
+                kfree(path_verification_worker);
                 kfree(dasd_reserve_req);
+        }
         return ret;
 }
 
@@ -3695,6 +3875,7 @@ static void __exit
 dasd_eckd_cleanup(void)
 {
         ccw_driver_unregister(&dasd_eckd_driver);
+        kfree(path_verification_worker);
         kfree(dasd_reserve_req);
 }