| Dan Williams | 3d88002 | 2015-05-31 15:02:11 -0400 | [diff] [blame] | 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 (err == 0) |
| 37 | return 0; |
| 38 | |
| 39 | if (rc == err) |
| 40 | return -ENODEV; |
| 41 | |
| 42 | /* |
| 43 | * Given multiple namespaces per region, we do not want to |
| 44 | * disable all the successfully registered peer namespaces upon |
| 45 | * a single registration failure. If userspace is missing a |
| 46 | * namespace that it expects it can disable/re-enable the region |
| 47 | * to retry discovery after correcting the failure. |
| 48 | * <regionX>/namespaces returns the current |
| 49 | * "<async-registered>/<total>" namespace count. |
| 50 | */ |
| 51 | dev_err(dev, "failed to register %d namespace%s, continuing...\n", |
| 52 | err, err == 1 ? "" : "s"); |
| 53 | return 0; |
| 54 | } |
| 55 | |
| 56 | static int child_unregister(struct device *dev, void *data) |
| 57 | { |
| 58 | nd_device_unregister(dev, ND_SYNC); |
| 59 | return 0; |
| 60 | } |
| 61 | |
| 62 | static int nd_region_remove(struct device *dev) |
| 63 | { |
| 64 | /* flush attribute readers and disable */ |
| 65 | nvdimm_bus_lock(dev); |
| 66 | dev_set_drvdata(dev, NULL); |
| 67 | nvdimm_bus_unlock(dev); |
| 68 | |
| 69 | device_for_each_child(dev, NULL, child_unregister); |
| 70 | return 0; |
| 71 | } |
| 72 | |
| 73 | static struct nd_device_driver nd_region_driver = { |
| 74 | .probe = nd_region_probe, |
| 75 | .remove = nd_region_remove, |
| 76 | .drv = { |
| 77 | .name = "nd_region", |
| 78 | }, |
| 79 | .type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM, |
| 80 | }; |
| 81 | |
| 82 | int __init nd_region_init(void) |
| 83 | { |
| 84 | return nd_driver_register(&nd_region_driver); |
| 85 | } |
| 86 | |
| 87 | void nd_region_exit(void) |
| 88 | { |
| 89 | driver_unregister(&nd_region_driver.drv); |
| 90 | } |
| 91 | |
| 92 | MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM); |
| 93 | MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK); |