1 /* 2 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of version 2 of the GNU General Public License as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 */ 13 #include <linux/module.h> 14 #include <linux/device.h> 15 #include <linux/nd.h> 16 #include "nd.h" 17 18 static int nd_region_probe(struct device *dev) 19 { 20 int err; 21 struct nd_region_namespaces *num_ns; 22 struct nd_region *nd_region = to_nd_region(dev); 23 int rc = nd_region_register_namespaces(nd_region, &err); 24 25 num_ns = devm_kzalloc(dev, sizeof(*num_ns), GFP_KERNEL); 26 if (!num_ns) 27 return -ENOMEM; 28 29 if (rc < 0) 30 return rc; 31 32 num_ns->active = rc; 33 num_ns->count = rc + err; 34 dev_set_drvdata(dev, num_ns); 35 36 if (rc && err && rc == err) 37 return -ENODEV; 38 39 nd_region->btt_seed = nd_btt_create(nd_region); 40 if (err == 0) 41 return 0; 42 43 /* 44 * Given multiple namespaces per region, we do not want to 45 * disable all the successfully registered peer namespaces upon 46 * a single registration failure. If userspace is missing a 47 * namespace that it expects it can disable/re-enable the region 48 * to retry discovery after correcting the failure. 49 * <regionX>/namespaces returns the current 50 * "<async-registered>/<total>" namespace count. 51 */ 52 dev_err(dev, "failed to register %d namespace%s, continuing...\n", 53 err, err == 1 ? "" : "s"); 54 return 0; 55 } 56 57 static int child_unregister(struct device *dev, void *data) 58 { 59 nd_device_unregister(dev, ND_SYNC); 60 return 0; 61 } 62 63 static int nd_region_remove(struct device *dev) 64 { 65 struct nd_region *nd_region = to_nd_region(dev); 66 67 /* flush attribute readers and disable */ 68 nvdimm_bus_lock(dev); 69 nd_region->ns_seed = NULL; 70 nd_region->btt_seed = NULL; 71 dev_set_drvdata(dev, NULL); 72 nvdimm_bus_unlock(dev); 73 74 device_for_each_child(dev, NULL, child_unregister); 75 return 0; 76 } 77 78 static struct nd_device_driver nd_region_driver = { 79 .probe = nd_region_probe, 80 .remove = nd_region_remove, 81 .drv = { 82 .name = "nd_region", 83 }, 84 .type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM, 85 }; 86 87 int __init nd_region_init(void) 88 { 89 return nd_driver_register(&nd_region_driver); 90 } 91 92 void nd_region_exit(void) 93 { 94 driver_unregister(&nd_region_driver.drv); 95 } 96 97 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM); 98 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK); 99