Merge tag 'riscv-for-linus-4.15-rc2_cleanups' of git://git.kernel.org/pub/scm/linux...
[linux/fpc-iii.git] / drivers / nvdimm / blk.c
blob345acca576b3c077b68e339437dd2e54ae76384a
1 /*
2 * NVDIMM Block Window Driver
3 * Copyright (c) 2014, Intel Corporation.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
15 #include <linux/blkdev.h>
16 #include <linux/fs.h>
17 #include <linux/genhd.h>
18 #include <linux/module.h>
19 #include <linux/moduleparam.h>
20 #include <linux/nd.h>
21 #include <linux/sizes.h>
22 #include "nd.h"
24 static u32 nsblk_meta_size(struct nd_namespace_blk *nsblk)
26 return nsblk->lbasize - ((nsblk->lbasize >= 4096) ? 4096 : 512);
29 static u32 nsblk_internal_lbasize(struct nd_namespace_blk *nsblk)
31 return roundup(nsblk->lbasize, INT_LBASIZE_ALIGNMENT);
34 static u32 nsblk_sector_size(struct nd_namespace_blk *nsblk)
36 return nsblk->lbasize - nsblk_meta_size(nsblk);
39 static resource_size_t to_dev_offset(struct nd_namespace_blk *nsblk,
40 resource_size_t ns_offset, unsigned int len)
42 int i;
44 for (i = 0; i < nsblk->num_resources; i++) {
45 if (ns_offset < resource_size(nsblk->res[i])) {
46 if (ns_offset + len > resource_size(nsblk->res[i])) {
47 dev_WARN_ONCE(&nsblk->common.dev, 1,
48 "illegal request\n");
49 return SIZE_MAX;
51 return nsblk->res[i]->start + ns_offset;
53 ns_offset -= resource_size(nsblk->res[i]);
56 dev_WARN_ONCE(&nsblk->common.dev, 1, "request out of range\n");
57 return SIZE_MAX;
60 static struct nd_blk_region *to_ndbr(struct nd_namespace_blk *nsblk)
62 struct nd_region *nd_region;
63 struct device *parent;
65 parent = nsblk->common.dev.parent;
66 nd_region = container_of(parent, struct nd_region, dev);
67 return container_of(nd_region, struct nd_blk_region, nd_region);
70 #ifdef CONFIG_BLK_DEV_INTEGRITY
71 static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
72 struct bio_integrity_payload *bip, u64 lba, int rw)
74 struct nd_blk_region *ndbr = to_ndbr(nsblk);
75 unsigned int len = nsblk_meta_size(nsblk);
76 resource_size_t dev_offset, ns_offset;
77 u32 internal_lbasize, sector_size;
78 int err = 0;
80 internal_lbasize = nsblk_internal_lbasize(nsblk);
81 sector_size = nsblk_sector_size(nsblk);
82 ns_offset = lba * internal_lbasize + sector_size;
83 dev_offset = to_dev_offset(nsblk, ns_offset, len);
84 if (dev_offset == SIZE_MAX)
85 return -EIO;
87 while (len) {
88 unsigned int cur_len;
89 struct bio_vec bv;
90 void *iobuf;
92 bv = bvec_iter_bvec(bip->bip_vec, bip->bip_iter);
94 * The 'bv' obtained from bvec_iter_bvec has its .bv_len and
95 * .bv_offset already adjusted for iter->bi_bvec_done, and we
96 * can use those directly
99 cur_len = min(len, bv.bv_len);
100 iobuf = kmap_atomic(bv.bv_page);
101 err = ndbr->do_io(ndbr, dev_offset, iobuf + bv.bv_offset,
102 cur_len, rw);
103 kunmap_atomic(iobuf);
104 if (err)
105 return err;
107 len -= cur_len;
108 dev_offset += cur_len;
109 if (!bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len))
110 return -EIO;
113 return err;
116 #else /* CONFIG_BLK_DEV_INTEGRITY */
117 static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
118 struct bio_integrity_payload *bip, u64 lba, int rw)
120 return 0;
122 #endif
124 static int nsblk_do_bvec(struct nd_namespace_blk *nsblk,
125 struct bio_integrity_payload *bip, struct page *page,
126 unsigned int len, unsigned int off, int rw, sector_t sector)
128 struct nd_blk_region *ndbr = to_ndbr(nsblk);
129 resource_size_t dev_offset, ns_offset;
130 u32 internal_lbasize, sector_size;
131 int err = 0;
132 void *iobuf;
133 u64 lba;
135 internal_lbasize = nsblk_internal_lbasize(nsblk);
136 sector_size = nsblk_sector_size(nsblk);
137 while (len) {
138 unsigned int cur_len;
141 * If we don't have an integrity payload, we don't have to
142 * split the bvec into sectors, as this would cause unnecessary
143 * Block Window setup/move steps. the do_io routine is capable
144 * of handling len <= PAGE_SIZE.
146 cur_len = bip ? min(len, sector_size) : len;
148 lba = div_u64(sector << SECTOR_SHIFT, sector_size);
149 ns_offset = lba * internal_lbasize;
150 dev_offset = to_dev_offset(nsblk, ns_offset, cur_len);
151 if (dev_offset == SIZE_MAX)
152 return -EIO;
154 iobuf = kmap_atomic(page);
155 err = ndbr->do_io(ndbr, dev_offset, iobuf + off, cur_len, rw);
156 kunmap_atomic(iobuf);
157 if (err)
158 return err;
160 if (bip) {
161 err = nd_blk_rw_integrity(nsblk, bip, lba, rw);
162 if (err)
163 return err;
165 len -= cur_len;
166 off += cur_len;
167 sector += sector_size >> SECTOR_SHIFT;
170 return err;
173 static blk_qc_t nd_blk_make_request(struct request_queue *q, struct bio *bio)
175 struct bio_integrity_payload *bip;
176 struct nd_namespace_blk *nsblk;
177 struct bvec_iter iter;
178 unsigned long start;
179 struct bio_vec bvec;
180 int err = 0, rw;
181 bool do_acct;
183 if (!bio_integrity_prep(bio))
184 return BLK_QC_T_NONE;
186 bip = bio_integrity(bio);
187 nsblk = q->queuedata;
188 rw = bio_data_dir(bio);
189 do_acct = nd_iostat_start(bio, &start);
190 bio_for_each_segment(bvec, bio, iter) {
191 unsigned int len = bvec.bv_len;
193 BUG_ON(len > PAGE_SIZE);
194 err = nsblk_do_bvec(nsblk, bip, bvec.bv_page, len,
195 bvec.bv_offset, rw, iter.bi_sector);
196 if (err) {
197 dev_dbg(&nsblk->common.dev,
198 "io error in %s sector %lld, len %d,\n",
199 (rw == READ) ? "READ" : "WRITE",
200 (unsigned long long) iter.bi_sector, len);
201 bio->bi_status = errno_to_blk_status(err);
202 break;
205 if (do_acct)
206 nd_iostat_end(bio, start);
208 bio_endio(bio);
209 return BLK_QC_T_NONE;
212 static int nsblk_rw_bytes(struct nd_namespace_common *ndns,
213 resource_size_t offset, void *iobuf, size_t n, int rw,
214 unsigned long flags)
216 struct nd_namespace_blk *nsblk = to_nd_namespace_blk(&ndns->dev);
217 struct nd_blk_region *ndbr = to_ndbr(nsblk);
218 resource_size_t dev_offset;
220 dev_offset = to_dev_offset(nsblk, offset, n);
222 if (unlikely(offset + n > nsblk->size)) {
223 dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
224 return -EFAULT;
227 if (dev_offset == SIZE_MAX)
228 return -EIO;
230 return ndbr->do_io(ndbr, dev_offset, iobuf, n, rw);
233 static const struct block_device_operations nd_blk_fops = {
234 .owner = THIS_MODULE,
235 .revalidate_disk = nvdimm_revalidate_disk,
238 static void nd_blk_release_queue(void *q)
240 blk_cleanup_queue(q);
243 static void nd_blk_release_disk(void *disk)
245 del_gendisk(disk);
246 put_disk(disk);
249 static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
251 struct device *dev = &nsblk->common.dev;
252 resource_size_t available_disk_size;
253 struct request_queue *q;
254 struct gendisk *disk;
255 u64 internal_nlba;
257 internal_nlba = div_u64(nsblk->size, nsblk_internal_lbasize(nsblk));
258 available_disk_size = internal_nlba * nsblk_sector_size(nsblk);
260 q = blk_alloc_queue(GFP_KERNEL);
261 if (!q)
262 return -ENOMEM;
263 if (devm_add_action_or_reset(dev, nd_blk_release_queue, q))
264 return -ENOMEM;
266 blk_queue_make_request(q, nd_blk_make_request);
267 blk_queue_max_hw_sectors(q, UINT_MAX);
268 blk_queue_logical_block_size(q, nsblk_sector_size(nsblk));
269 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
270 q->queuedata = nsblk;
272 disk = alloc_disk(0);
273 if (!disk)
274 return -ENOMEM;
276 disk->first_minor = 0;
277 disk->fops = &nd_blk_fops;
278 disk->queue = q;
279 disk->flags = GENHD_FL_EXT_DEVT;
280 nvdimm_namespace_disk_name(&nsblk->common, disk->disk_name);
281 set_capacity(disk, 0);
282 device_add_disk(dev, disk);
284 if (devm_add_action_or_reset(dev, nd_blk_release_disk, disk))
285 return -ENOMEM;
287 if (nsblk_meta_size(nsblk)) {
288 int rc = nd_integrity_init(disk, nsblk_meta_size(nsblk));
290 if (rc)
291 return rc;
294 set_capacity(disk, available_disk_size >> SECTOR_SHIFT);
295 revalidate_disk(disk);
296 return 0;
299 static int nd_blk_probe(struct device *dev)
301 struct nd_namespace_common *ndns;
302 struct nd_namespace_blk *nsblk;
304 ndns = nvdimm_namespace_common_probe(dev);
305 if (IS_ERR(ndns))
306 return PTR_ERR(ndns);
308 nsblk = to_nd_namespace_blk(&ndns->dev);
309 nsblk->size = nvdimm_namespace_capacity(ndns);
310 dev_set_drvdata(dev, nsblk);
312 ndns->rw_bytes = nsblk_rw_bytes;
313 if (is_nd_btt(dev))
314 return nvdimm_namespace_attach_btt(ndns);
315 else if (nd_btt_probe(dev, ndns) == 0) {
316 /* we'll come back as btt-blk */
317 return -ENXIO;
318 } else
319 return nsblk_attach_disk(nsblk);
322 static int nd_blk_remove(struct device *dev)
324 if (is_nd_btt(dev))
325 nvdimm_namespace_detach_btt(to_nd_btt(dev));
326 return 0;
329 static struct nd_device_driver nd_blk_driver = {
330 .probe = nd_blk_probe,
331 .remove = nd_blk_remove,
332 .drv = {
333 .name = "nd_blk",
335 .type = ND_DRIVER_NAMESPACE_BLK,
338 static int __init nd_blk_init(void)
340 return nd_driver_register(&nd_blk_driver);
343 static void __exit nd_blk_exit(void)
345 driver_unregister(&nd_blk_driver.drv);
348 MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
349 MODULE_LICENSE("GPL v2");
350 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_BLK);
351 module_init(nd_blk_init);
352 module_exit(nd_blk_exit);