Merge tag 'drm-misc-next-2021-07-22' of git://anongit.freedesktop.org/drm/drm-misc...
[linux-2.6-microblaze.git] / drivers / nvdimm / blk.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * NVDIMM Block Window Driver
4  * Copyright (c) 2014, Intel Corporation.
5  */
6
7 #include <linux/blkdev.h>
8 #include <linux/fs.h>
9 #include <linux/genhd.h>
10 #include <linux/module.h>
11 #include <linux/moduleparam.h>
12 #include <linux/nd.h>
13 #include <linux/sizes.h>
14 #include "nd.h"
15
16 static u32 nsblk_meta_size(struct nd_namespace_blk *nsblk)
17 {
18         return nsblk->lbasize - ((nsblk->lbasize >= 4096) ? 4096 : 512);
19 }
20
21 static u32 nsblk_internal_lbasize(struct nd_namespace_blk *nsblk)
22 {
23         return roundup(nsblk->lbasize, INT_LBASIZE_ALIGNMENT);
24 }
25
26 static u32 nsblk_sector_size(struct nd_namespace_blk *nsblk)
27 {
28         return nsblk->lbasize - nsblk_meta_size(nsblk);
29 }
30
31 static resource_size_t to_dev_offset(struct nd_namespace_blk *nsblk,
32                                 resource_size_t ns_offset, unsigned int len)
33 {
34         int i;
35
36         for (i = 0; i < nsblk->num_resources; i++) {
37                 if (ns_offset < resource_size(nsblk->res[i])) {
38                         if (ns_offset + len > resource_size(nsblk->res[i])) {
39                                 dev_WARN_ONCE(&nsblk->common.dev, 1,
40                                         "illegal request\n");
41                                 return SIZE_MAX;
42                         }
43                         return nsblk->res[i]->start + ns_offset;
44                 }
45                 ns_offset -= resource_size(nsblk->res[i]);
46         }
47
48         dev_WARN_ONCE(&nsblk->common.dev, 1, "request out of range\n");
49         return SIZE_MAX;
50 }
51
52 static struct nd_blk_region *to_ndbr(struct nd_namespace_blk *nsblk)
53 {
54         struct nd_region *nd_region;
55         struct device *parent;
56
57         parent = nsblk->common.dev.parent;
58         nd_region = container_of(parent, struct nd_region, dev);
59         return container_of(nd_region, struct nd_blk_region, nd_region);
60 }
61
62 #ifdef CONFIG_BLK_DEV_INTEGRITY
63 static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
64                 struct bio_integrity_payload *bip, u64 lba, int rw)
65 {
66         struct nd_blk_region *ndbr = to_ndbr(nsblk);
67         unsigned int len = nsblk_meta_size(nsblk);
68         resource_size_t dev_offset, ns_offset;
69         u32 internal_lbasize, sector_size;
70         int err = 0;
71
72         internal_lbasize = nsblk_internal_lbasize(nsblk);
73         sector_size = nsblk_sector_size(nsblk);
74         ns_offset = lba * internal_lbasize + sector_size;
75         dev_offset = to_dev_offset(nsblk, ns_offset, len);
76         if (dev_offset == SIZE_MAX)
77                 return -EIO;
78
79         while (len) {
80                 unsigned int cur_len;
81                 struct bio_vec bv;
82                 void *iobuf;
83
84                 bv = bvec_iter_bvec(bip->bip_vec, bip->bip_iter);
85                 /*
86                  * The 'bv' obtained from bvec_iter_bvec has its .bv_len and
87                  * .bv_offset already adjusted for iter->bi_bvec_done, and we
88                  * can use those directly
89                  */
90
91                 cur_len = min(len, bv.bv_len);
92                 iobuf = kmap_atomic(bv.bv_page);
93                 err = ndbr->do_io(ndbr, dev_offset, iobuf + bv.bv_offset,
94                                 cur_len, rw);
95                 kunmap_atomic(iobuf);
96                 if (err)
97                         return err;
98
99                 len -= cur_len;
100                 dev_offset += cur_len;
101                 if (!bvec_iter_advance(bip->bip_vec, &bip->bip_iter, cur_len))
102                         return -EIO;
103         }
104
105         return err;
106 }
107
108 #else /* CONFIG_BLK_DEV_INTEGRITY */
109 static int nd_blk_rw_integrity(struct nd_namespace_blk *nsblk,
110                 struct bio_integrity_payload *bip, u64 lba, int rw)
111 {
112         return 0;
113 }
114 #endif
115
116 static int nsblk_do_bvec(struct nd_namespace_blk *nsblk,
117                 struct bio_integrity_payload *bip, struct page *page,
118                 unsigned int len, unsigned int off, int rw, sector_t sector)
119 {
120         struct nd_blk_region *ndbr = to_ndbr(nsblk);
121         resource_size_t dev_offset, ns_offset;
122         u32 internal_lbasize, sector_size;
123         int err = 0;
124         void *iobuf;
125         u64 lba;
126
127         internal_lbasize = nsblk_internal_lbasize(nsblk);
128         sector_size = nsblk_sector_size(nsblk);
129         while (len) {
130                 unsigned int cur_len;
131
132                 /*
133                  * If we don't have an integrity payload, we don't have to
134                  * split the bvec into sectors, as this would cause unnecessary
135                  * Block Window setup/move steps. the do_io routine is capable
136                  * of handling len <= PAGE_SIZE.
137                  */
138                 cur_len = bip ? min(len, sector_size) : len;
139
140                 lba = div_u64(sector << SECTOR_SHIFT, sector_size);
141                 ns_offset = lba * internal_lbasize;
142                 dev_offset = to_dev_offset(nsblk, ns_offset, cur_len);
143                 if (dev_offset == SIZE_MAX)
144                         return -EIO;
145
146                 iobuf = kmap_atomic(page);
147                 err = ndbr->do_io(ndbr, dev_offset, iobuf + off, cur_len, rw);
148                 kunmap_atomic(iobuf);
149                 if (err)
150                         return err;
151
152                 if (bip) {
153                         err = nd_blk_rw_integrity(nsblk, bip, lba, rw);
154                         if (err)
155                                 return err;
156                 }
157                 len -= cur_len;
158                 off += cur_len;
159                 sector += sector_size >> SECTOR_SHIFT;
160         }
161
162         return err;
163 }
164
165 static blk_qc_t nd_blk_submit_bio(struct bio *bio)
166 {
167         struct bio_integrity_payload *bip;
168         struct nd_namespace_blk *nsblk = bio->bi_bdev->bd_disk->private_data;
169         struct bvec_iter iter;
170         unsigned long start;
171         struct bio_vec bvec;
172         int err = 0, rw;
173         bool do_acct;
174
175         if (!bio_integrity_prep(bio))
176                 return BLK_QC_T_NONE;
177
178         bip = bio_integrity(bio);
179         rw = bio_data_dir(bio);
180         do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue);
181         if (do_acct)
182                 start = bio_start_io_acct(bio);
183         bio_for_each_segment(bvec, bio, iter) {
184                 unsigned int len = bvec.bv_len;
185
186                 BUG_ON(len > PAGE_SIZE);
187                 err = nsblk_do_bvec(nsblk, bip, bvec.bv_page, len,
188                                 bvec.bv_offset, rw, iter.bi_sector);
189                 if (err) {
190                         dev_dbg(&nsblk->common.dev,
191                                         "io error in %s sector %lld, len %d,\n",
192                                         (rw == READ) ? "READ" : "WRITE",
193                                         (unsigned long long) iter.bi_sector, len);
194                         bio->bi_status = errno_to_blk_status(err);
195                         break;
196                 }
197         }
198         if (do_acct)
199                 bio_end_io_acct(bio, start);
200
201         bio_endio(bio);
202         return BLK_QC_T_NONE;
203 }
204
205 static int nsblk_rw_bytes(struct nd_namespace_common *ndns,
206                 resource_size_t offset, void *iobuf, size_t n, int rw,
207                 unsigned long flags)
208 {
209         struct nd_namespace_blk *nsblk = to_nd_namespace_blk(&ndns->dev);
210         struct nd_blk_region *ndbr = to_ndbr(nsblk);
211         resource_size_t dev_offset;
212
213         dev_offset = to_dev_offset(nsblk, offset, n);
214
215         if (unlikely(offset + n > nsblk->size)) {
216                 dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
217                 return -EFAULT;
218         }
219
220         if (dev_offset == SIZE_MAX)
221                 return -EIO;
222
223         return ndbr->do_io(ndbr, dev_offset, iobuf, n, rw);
224 }
225
226 static const struct block_device_operations nd_blk_fops = {
227         .owner = THIS_MODULE,
228         .submit_bio =  nd_blk_submit_bio,
229 };
230
231 static void nd_blk_release_disk(void *disk)
232 {
233         del_gendisk(disk);
234         blk_cleanup_disk(disk);
235 }
236
237 static int nsblk_attach_disk(struct nd_namespace_blk *nsblk)
238 {
239         struct device *dev = &nsblk->common.dev;
240         resource_size_t available_disk_size;
241         struct gendisk *disk;
242         u64 internal_nlba;
243
244         internal_nlba = div_u64(nsblk->size, nsblk_internal_lbasize(nsblk));
245         available_disk_size = internal_nlba * nsblk_sector_size(nsblk);
246
247         disk = blk_alloc_disk(NUMA_NO_NODE);
248         if (!disk)
249                 return -ENOMEM;
250
251         disk->fops              = &nd_blk_fops;
252         disk->private_data      = nsblk;
253         nvdimm_namespace_disk_name(&nsblk->common, disk->disk_name);
254
255         blk_queue_max_hw_sectors(disk->queue, UINT_MAX);
256         blk_queue_logical_block_size(disk->queue, nsblk_sector_size(nsblk));
257         blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
258
259         if (devm_add_action_or_reset(dev, nd_blk_release_disk, disk))
260                 return -ENOMEM;
261
262         if (nsblk_meta_size(nsblk)) {
263                 int rc = nd_integrity_init(disk, nsblk_meta_size(nsblk));
264
265                 if (rc)
266                         return rc;
267         }
268
269         set_capacity(disk, available_disk_size >> SECTOR_SHIFT);
270         device_add_disk(dev, disk, NULL);
271         nvdimm_check_and_set_ro(disk);
272         return 0;
273 }
274
275 static int nd_blk_probe(struct device *dev)
276 {
277         struct nd_namespace_common *ndns;
278         struct nd_namespace_blk *nsblk;
279
280         ndns = nvdimm_namespace_common_probe(dev);
281         if (IS_ERR(ndns))
282                 return PTR_ERR(ndns);
283
284         nsblk = to_nd_namespace_blk(&ndns->dev);
285         nsblk->size = nvdimm_namespace_capacity(ndns);
286         dev_set_drvdata(dev, nsblk);
287
288         ndns->rw_bytes = nsblk_rw_bytes;
289         if (is_nd_btt(dev))
290                 return nvdimm_namespace_attach_btt(ndns);
291         else if (nd_btt_probe(dev, ndns) == 0) {
292                 /* we'll come back as btt-blk */
293                 return -ENXIO;
294         } else
295                 return nsblk_attach_disk(nsblk);
296 }
297
298 static void nd_blk_remove(struct device *dev)
299 {
300         if (is_nd_btt(dev))
301                 nvdimm_namespace_detach_btt(to_nd_btt(dev));
302 }
303
304 static struct nd_device_driver nd_blk_driver = {
305         .probe = nd_blk_probe,
306         .remove = nd_blk_remove,
307         .drv = {
308                 .name = "nd_blk",
309         },
310         .type = ND_DRIVER_NAMESPACE_BLK,
311 };
312
313 static int __init nd_blk_init(void)
314 {
315         return nd_driver_register(&nd_blk_driver);
316 }
317
318 static void __exit nd_blk_exit(void)
319 {
320         driver_unregister(&nd_blk_driver.drv);
321 }
322
323 MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
324 MODULE_LICENSE("GPL v2");
325 MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_BLK);
326 module_init(nd_blk_init);
327 module_exit(nd_blk_exit);