2 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
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.
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.
13 #include <linux/device.h>
14 #include <linux/sizes.h>
15 #include <linux/pmem.h>
21 void __nd_detach_ndns(struct device *dev, struct nd_namespace_common **_ndns)
23 struct nd_namespace_common *ndns = *_ndns;
25 dev_WARN_ONCE(dev, !mutex_is_locked(&ndns->dev.mutex)
26 || ndns->claim != dev,
27 "%s: invalid claim\n", __func__);
30 put_device(&ndns->dev);
33 void nd_detach_ndns(struct device *dev,
34 struct nd_namespace_common **_ndns)
36 struct nd_namespace_common *ndns = *_ndns;
40 get_device(&ndns->dev);
41 device_lock(&ndns->dev);
42 __nd_detach_ndns(dev, _ndns);
43 device_unlock(&ndns->dev);
44 put_device(&ndns->dev);
47 bool __nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach,
48 struct nd_namespace_common **_ndns)
52 dev_WARN_ONCE(dev, !mutex_is_locked(&attach->dev.mutex)
54 "%s: invalid claim\n", __func__);
57 get_device(&attach->dev);
61 bool nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach,
62 struct nd_namespace_common **_ndns)
66 device_lock(&attach->dev);
67 claimed = __nd_attach_ndns(dev, attach, _ndns);
68 device_unlock(&attach->dev);
72 static int namespace_match(struct device *dev, void *data)
76 return strcmp(name, dev_name(dev)) == 0;
79 static bool is_idle(struct device *dev, struct nd_namespace_common *ndns)
81 struct nd_region *nd_region = to_nd_region(dev->parent);
82 struct device *seed = NULL;
85 seed = nd_region->btt_seed;
86 else if (is_nd_pfn(dev))
87 seed = nd_region->pfn_seed;
88 else if (is_nd_dax(dev))
89 seed = nd_region->dax_seed;
91 if (seed == dev || ndns || dev->driver)
96 struct nd_pfn *to_nd_pfn_safe(struct device *dev)
99 * pfn device attributes are re-used by dax device instances, so we
100 * need to be careful to correct device-to-nd_pfn conversion.
103 return to_nd_pfn(dev);
105 if (is_nd_dax(dev)) {
106 struct nd_dax *nd_dax = to_nd_dax(dev);
108 return &nd_dax->nd_pfn;
115 static void nd_detach_and_reset(struct device *dev,
116 struct nd_namespace_common **_ndns)
118 /* detach the namespace and destroy / reset the device */
119 nd_detach_ndns(dev, _ndns);
120 if (is_idle(dev, *_ndns)) {
121 nd_device_unregister(dev, ND_ASYNC);
122 } else if (is_nd_btt(dev)) {
123 struct nd_btt *nd_btt = to_nd_btt(dev);
128 } else if (is_nd_pfn(dev) || is_nd_dax(dev)) {
129 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
133 nd_pfn->mode = PFN_MODE_NONE;
137 ssize_t nd_namespace_store(struct device *dev,
138 struct nd_namespace_common **_ndns, const char *buf,
141 struct nd_namespace_common *ndns;
142 struct device *found;
146 dev_dbg(dev, "%s: -EBUSY\n", __func__);
150 name = kstrndup(buf, len, GFP_KERNEL);
155 if (strncmp(name, "namespace", 9) == 0 || strcmp(name, "") == 0)
163 if (strcmp(name, "") == 0) {
164 nd_detach_and_reset(dev, _ndns);
167 dev_dbg(dev, "namespace already set to: %s\n",
168 dev_name(&ndns->dev));
173 found = device_find_child(dev->parent, name, namespace_match);
175 dev_dbg(dev, "'%s' not found under %s\n", name,
176 dev_name(dev->parent));
181 ndns = to_ndns(found);
182 if (__nvdimm_namespace_capacity(ndns) < SZ_16M) {
183 dev_dbg(dev, "%s too small to host\n", name);
188 WARN_ON_ONCE(!is_nvdimm_bus_locked(dev));
189 if (!nd_attach_ndns(dev, ndns, _ndns)) {
190 dev_dbg(dev, "%s already claimed\n",
191 dev_name(&ndns->dev));
196 put_device(&ndns->dev); /* from device_find_child */
203 * nd_sb_checksum: compute checksum for a generic info block
205 * Returns a fletcher64 checksum of everything in the given info block
206 * except the last field (since that's where the checksum lives).
208 u64 nd_sb_checksum(struct nd_gen_sb *nd_gen_sb)
213 BUILD_BUG_ON(sizeof(struct btt_sb) != SZ_4K);
214 BUILD_BUG_ON(sizeof(struct nd_pfn_sb) != SZ_4K);
215 BUILD_BUG_ON(sizeof(struct nd_gen_sb) != SZ_4K);
217 sum_save = nd_gen_sb->checksum;
218 nd_gen_sb->checksum = 0;
219 sum = nd_fletcher64(nd_gen_sb, sizeof(*nd_gen_sb), 1);
220 nd_gen_sb->checksum = sum_save;
223 EXPORT_SYMBOL(nd_sb_checksum);
225 static int nsio_rw_bytes(struct nd_namespace_common *ndns,
226 resource_size_t offset, void *buf, size_t size, int rw)
228 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
230 if (unlikely(offset + size > nsio->size)) {
231 dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
236 unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);
238 if (unlikely(is_bad_pmem(&nsio->bb, offset / 512, sz_align)))
240 return memcpy_from_pmem(buf, nsio->addr + offset, size);
242 memcpy_to_pmem(nsio->addr + offset, buf, size);
249 int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio)
251 struct resource *res = &nsio->res;
252 struct nd_namespace_common *ndns = &nsio->common;
254 nsio->size = resource_size(res);
255 if (!devm_request_mem_region(dev, res->start, resource_size(res),
257 dev_warn(dev, "could not reserve region %pR\n", res);
261 ndns->rw_bytes = nsio_rw_bytes;
262 if (devm_init_badblocks(dev, &nsio->bb))
264 nvdimm_badblocks_populate(to_nd_region(ndns->dev.parent), &nsio->bb,
267 nsio->addr = devm_memremap(dev, res->start, resource_size(res),
269 if (IS_ERR(nsio->addr))
270 return PTR_ERR(nsio->addr);
273 EXPORT_SYMBOL_GPL(devm_nsio_enable);
275 void devm_nsio_disable(struct device *dev, struct nd_namespace_io *nsio)
277 struct resource *res = &nsio->res;
279 devm_memunmap(dev, nsio->addr);
280 devm_exit_badblocks(dev, &nsio->bb);
281 devm_release_mem_region(dev, res->start, resource_size(res));
283 EXPORT_SYMBOL_GPL(devm_nsio_disable);