1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */ 3 #include <linux/memremap.h> 4 #include <linux/module.h> 5 #include <linux/pfn_t.h> 6 #include "../nvdimm/pfn.h" 7 #include "../nvdimm/nd.h" 8 #include "bus.h" 9 __dax_pmem_probe(struct device * dev)10 static struct dev_dax *__dax_pmem_probe(struct device *dev) 11 { 12 struct range range; 13 int rc, id, region_id; 14 resource_size_t offset; 15 struct nd_pfn_sb *pfn_sb; 16 struct dev_dax_data data; 17 struct nd_namespace_io *nsio; 18 struct dax_region *dax_region; 19 struct dev_pagemap pgmap = { }; 20 struct nd_namespace_common *ndns; 21 struct nd_dax *nd_dax = to_nd_dax(dev); 22 struct nd_pfn *nd_pfn = &nd_dax->nd_pfn; 23 struct nd_region *nd_region = to_nd_region(dev->parent); 24 25 ndns = nvdimm_namespace_common_probe(dev); 26 if (IS_ERR(ndns)) 27 return ERR_CAST(ndns); 28 29 /* parse the 'pfn' info block via ->rw_bytes */ 30 rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve()); 31 if (rc) 32 return ERR_PTR(rc); 33 rc = nvdimm_setup_pfn(nd_pfn, &pgmap); 34 if (rc) 35 return ERR_PTR(rc); 36 devm_namespace_disable(dev, ndns); 37 38 /* reserve the metadata area, device-dax will reserve the data */ 39 pfn_sb = nd_pfn->pfn_sb; 40 offset = le64_to_cpu(pfn_sb->dataoff); 41 nsio = to_nd_namespace_io(&ndns->dev); 42 if (!devm_request_mem_region(dev, nsio->res.start, offset, 43 dev_name(&ndns->dev))) { 44 dev_warn(dev, "could not reserve metadata\n"); 45 return ERR_PTR(-EBUSY); 46 } 47 48 rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", ®ion_id, &id); 49 if (rc != 2) 50 return ERR_PTR(-EINVAL); 51 52 /* adjust the dax_region range to the start of data */ 53 range = pgmap.range; 54 range.start += offset; 55 dax_region = alloc_dax_region(dev, region_id, &range, 56 nd_region->target_node, le32_to_cpu(pfn_sb->align), 57 IORESOURCE_DAX_STATIC); 58 if (!dax_region) 59 return ERR_PTR(-ENOMEM); 60 61 data = (struct dev_dax_data) { 62 .dax_region = dax_region, 63 .id = id, 64 .pgmap = &pgmap, 65 .size = range_len(&range), 66 .memmap_on_memory = false, 67 }; 68 69 return devm_create_dev_dax(&data); 70 } 71 dax_pmem_probe(struct device * dev)72 static int dax_pmem_probe(struct device *dev) 73 { 74 return PTR_ERR_OR_ZERO(__dax_pmem_probe(dev)); 75 } 76 77 static struct nd_device_driver dax_pmem_driver = { 78 .probe = dax_pmem_probe, 79 .drv = { 80 .name = "dax_pmem", 81 }, 82 .type = ND_DRIVER_DAX_PMEM, 83 }; 84 dax_pmem_init(void)85 static int __init dax_pmem_init(void) 86 { 87 return nd_driver_register(&dax_pmem_driver); 88 } 89 module_init(dax_pmem_init); 90 dax_pmem_exit(void)91 static void __exit dax_pmem_exit(void) 92 { 93 driver_unregister(&dax_pmem_driver.drv); 94 } 95 module_exit(dax_pmem_exit); 96 97 MODULE_DESCRIPTION("PMEM DAX: direct access to persistent memory"); 98 MODULE_LICENSE("GPL v2"); 99 MODULE_AUTHOR("Intel Corporation"); 100 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DAX_PMEM); 101