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7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8#include <linux/uio.h>
9#include <linux/falloc.h>
10#include <linux/file.h>
11#include "nvmet.h"
12
13#define NVMET_MAX_MPOOL_BVEC 16
14#define NVMET_MIN_MPOOL_OBJ 16
15
16void nvmet_file_ns_disable(struct nvmet_ns *ns)
17{
18 if (ns->file) {
19 if (ns->buffered_io)
20 flush_workqueue(buffered_io_wq);
21 mempool_destroy(ns->bvec_pool);
22 ns->bvec_pool = NULL;
23 kmem_cache_destroy(ns->bvec_cache);
24 ns->bvec_cache = NULL;
25 fput(ns->file);
26 ns->file = NULL;
27 }
28}
29
30int nvmet_file_ns_enable(struct nvmet_ns *ns)
31{
32 int flags = O_RDWR | O_LARGEFILE;
33 struct kstat stat;
34 int ret;
35
36 if (!ns->buffered_io)
37 flags |= O_DIRECT;
38
39 ns->file = filp_open(ns->device_path, flags, 0);
40 if (IS_ERR(ns->file)) {
41 pr_err("failed to open file %s: (%ld)\n",
42 ns->device_path, PTR_ERR(ns->file));
43 return PTR_ERR(ns->file);
44 }
45
46 ret = vfs_getattr(&ns->file->f_path,
47 &stat, STATX_SIZE, AT_STATX_FORCE_SYNC);
48 if (ret)
49 goto err;
50
51 ns->size = stat.size;
52
53
54
55
56 ns->blksize_shift = min_t(u8,
57 file_inode(ns->file)->i_blkbits, 12);
58
59 ns->bvec_cache = kmem_cache_create("nvmet-bvec",
60 NVMET_MAX_MPOOL_BVEC * sizeof(struct bio_vec),
61 0, SLAB_HWCACHE_ALIGN, NULL);
62 if (!ns->bvec_cache) {
63 ret = -ENOMEM;
64 goto err;
65 }
66
67 ns->bvec_pool = mempool_create(NVMET_MIN_MPOOL_OBJ, mempool_alloc_slab,
68 mempool_free_slab, ns->bvec_cache);
69
70 if (!ns->bvec_pool) {
71 ret = -ENOMEM;
72 goto err;
73 }
74
75 return ret;
76err:
77 ns->size = 0;
78 ns->blksize_shift = 0;
79 nvmet_file_ns_disable(ns);
80 return ret;
81}
82
83static void nvmet_file_init_bvec(struct bio_vec *bv, struct scatterlist *sg)
84{
85 bv->bv_page = sg_page(sg);
86 bv->bv_offset = sg->offset;
87 bv->bv_len = sg->length;
88}
89
90static ssize_t nvmet_file_submit_bvec(struct nvmet_req *req, loff_t pos,
91 unsigned long nr_segs, size_t count, int ki_flags)
92{
93 struct kiocb *iocb = &req->f.iocb;
94 ssize_t (*call_iter)(struct kiocb *iocb, struct iov_iter *iter);
95 struct iov_iter iter;
96 int rw;
97
98 if (req->cmd->rw.opcode == nvme_cmd_write) {
99 if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
100 ki_flags |= IOCB_DSYNC;
101 call_iter = req->ns->file->f_op->write_iter;
102 rw = WRITE;
103 } else {
104 call_iter = req->ns->file->f_op->read_iter;
105 rw = READ;
106 }
107
108 iov_iter_bvec(&iter, rw, req->f.bvec, nr_segs, count);
109
110 iocb->ki_pos = pos;
111 iocb->ki_filp = req->ns->file;
112 iocb->ki_flags = ki_flags | iocb_flags(req->ns->file);
113
114 return call_iter(iocb, &iter);
115}
116
117static void nvmet_file_io_done(struct kiocb *iocb, long ret, long ret2)
118{
119 struct nvmet_req *req = container_of(iocb, struct nvmet_req, f.iocb);
120 u16 status = NVME_SC_SUCCESS;
121
122 if (req->f.bvec != req->inline_bvec) {
123 if (likely(req->f.mpool_alloc == false))
124 kfree(req->f.bvec);
125 else
126 mempool_free(req->f.bvec, req->ns->bvec_pool);
127 }
128
129 if (unlikely(ret != req->data_len))
130 status = errno_to_nvme_status(req, ret);
131 nvmet_req_complete(req, status);
132}
133
134static bool nvmet_file_execute_io(struct nvmet_req *req, int ki_flags)
135{
136 ssize_t nr_bvec = req->sg_cnt;
137 unsigned long bv_cnt = 0;
138 bool is_sync = false;
139 size_t len = 0, total_len = 0;
140 ssize_t ret = 0;
141 loff_t pos;
142 int i;
143 struct scatterlist *sg;
144
145 if (req->f.mpool_alloc && nr_bvec > NVMET_MAX_MPOOL_BVEC)
146 is_sync = true;
147
148 pos = le64_to_cpu(req->cmd->rw.slba) << req->ns->blksize_shift;
149 if (unlikely(pos + req->data_len > req->ns->size)) {
150 nvmet_req_complete(req, errno_to_nvme_status(req, -ENOSPC));
151 return true;
152 }
153
154 memset(&req->f.iocb, 0, sizeof(struct kiocb));
155 for_each_sg(req->sg, sg, req->sg_cnt, i) {
156 nvmet_file_init_bvec(&req->f.bvec[bv_cnt], sg);
157 len += req->f.bvec[bv_cnt].bv_len;
158 total_len += req->f.bvec[bv_cnt].bv_len;
159 bv_cnt++;
160
161 WARN_ON_ONCE((nr_bvec - 1) < 0);
162
163 if (unlikely(is_sync) &&
164 (nr_bvec - 1 == 0 || bv_cnt == NVMET_MAX_MPOOL_BVEC)) {
165 ret = nvmet_file_submit_bvec(req, pos, bv_cnt, len, 0);
166 if (ret < 0)
167 goto complete;
168
169 pos += len;
170 bv_cnt = 0;
171 len = 0;
172 }
173 nr_bvec--;
174 }
175
176 if (WARN_ON_ONCE(total_len != req->data_len)) {
177 ret = -EIO;
178 goto complete;
179 }
180
181 if (unlikely(is_sync)) {
182 ret = total_len;
183 goto complete;
184 }
185
186
187
188
189
190 if (!(ki_flags & IOCB_NOWAIT))
191 req->f.iocb.ki_complete = nvmet_file_io_done;
192
193 ret = nvmet_file_submit_bvec(req, pos, bv_cnt, total_len, ki_flags);
194
195 switch (ret) {
196 case -EIOCBQUEUED:
197 return true;
198 case -EAGAIN:
199 if (WARN_ON_ONCE(!(ki_flags & IOCB_NOWAIT)))
200 goto complete;
201 return false;
202 case -EOPNOTSUPP:
203
204
205
206
207
208 if ((ki_flags & IOCB_NOWAIT))
209 return false;
210 break;
211 }
212
213complete:
214 nvmet_file_io_done(&req->f.iocb, ret, 0);
215 return true;
216}
217
218static void nvmet_file_buffered_io_work(struct work_struct *w)
219{
220 struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
221
222 nvmet_file_execute_io(req, 0);
223}
224
225static void nvmet_file_submit_buffered_io(struct nvmet_req *req)
226{
227 INIT_WORK(&req->f.work, nvmet_file_buffered_io_work);
228 queue_work(buffered_io_wq, &req->f.work);
229}
230
231static void nvmet_file_execute_rw(struct nvmet_req *req)
232{
233 ssize_t nr_bvec = req->sg_cnt;
234
235 if (!req->sg_cnt || !nr_bvec) {
236 nvmet_req_complete(req, 0);
237 return;
238 }
239
240 if (nr_bvec > NVMET_MAX_INLINE_BIOVEC)
241 req->f.bvec = kmalloc_array(nr_bvec, sizeof(struct bio_vec),
242 GFP_KERNEL);
243 else
244 req->f.bvec = req->inline_bvec;
245
246 if (unlikely(!req->f.bvec)) {
247
248 req->f.bvec = mempool_alloc(req->ns->bvec_pool, GFP_KERNEL);
249 req->f.mpool_alloc = true;
250 } else
251 req->f.mpool_alloc = false;
252
253 if (req->ns->buffered_io) {
254 if (likely(!req->f.mpool_alloc) &&
255 nvmet_file_execute_io(req, IOCB_NOWAIT))
256 return;
257 nvmet_file_submit_buffered_io(req);
258 } else
259 nvmet_file_execute_io(req, 0);
260}
261
262u16 nvmet_file_flush(struct nvmet_req *req)
263{
264 return errno_to_nvme_status(req, vfs_fsync(req->ns->file, 1));
265}
266
267static void nvmet_file_flush_work(struct work_struct *w)
268{
269 struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
270
271 nvmet_req_complete(req, nvmet_file_flush(req));
272}
273
274static void nvmet_file_execute_flush(struct nvmet_req *req)
275{
276 INIT_WORK(&req->f.work, nvmet_file_flush_work);
277 schedule_work(&req->f.work);
278}
279
280static void nvmet_file_execute_discard(struct nvmet_req *req)
281{
282 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
283 struct nvme_dsm_range range;
284 loff_t offset, len;
285 u16 status = 0;
286 int ret;
287 int i;
288
289 for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
290 status = nvmet_copy_from_sgl(req, i * sizeof(range), &range,
291 sizeof(range));
292 if (status)
293 break;
294
295 offset = le64_to_cpu(range.slba) << req->ns->blksize_shift;
296 len = le32_to_cpu(range.nlb);
297 len <<= req->ns->blksize_shift;
298 if (offset + len > req->ns->size) {
299 req->error_slba = le64_to_cpu(range.slba);
300 status = errno_to_nvme_status(req, -ENOSPC);
301 break;
302 }
303
304 ret = vfs_fallocate(req->ns->file, mode, offset, len);
305 if (ret && ret != -EOPNOTSUPP) {
306 req->error_slba = le64_to_cpu(range.slba);
307 status = errno_to_nvme_status(req, ret);
308 break;
309 }
310 }
311
312 nvmet_req_complete(req, status);
313}
314
315static void nvmet_file_dsm_work(struct work_struct *w)
316{
317 struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
318
319 switch (le32_to_cpu(req->cmd->dsm.attributes)) {
320 case NVME_DSMGMT_AD:
321 nvmet_file_execute_discard(req);
322 return;
323 case NVME_DSMGMT_IDR:
324 case NVME_DSMGMT_IDW:
325 default:
326
327 nvmet_req_complete(req, 0);
328 return;
329 }
330}
331
332static void nvmet_file_execute_dsm(struct nvmet_req *req)
333{
334 INIT_WORK(&req->f.work, nvmet_file_dsm_work);
335 schedule_work(&req->f.work);
336}
337
338static void nvmet_file_write_zeroes_work(struct work_struct *w)
339{
340 struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
341 struct nvme_write_zeroes_cmd *write_zeroes = &req->cmd->write_zeroes;
342 int mode = FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE;
343 loff_t offset;
344 loff_t len;
345 int ret;
346
347 offset = le64_to_cpu(write_zeroes->slba) << req->ns->blksize_shift;
348 len = (((sector_t)le16_to_cpu(write_zeroes->length) + 1) <<
349 req->ns->blksize_shift);
350
351 if (unlikely(offset + len > req->ns->size)) {
352 nvmet_req_complete(req, errno_to_nvme_status(req, -ENOSPC));
353 return;
354 }
355
356 ret = vfs_fallocate(req->ns->file, mode, offset, len);
357 nvmet_req_complete(req, ret < 0 ? errno_to_nvme_status(req, ret) : 0);
358}
359
360static void nvmet_file_execute_write_zeroes(struct nvmet_req *req)
361{
362 INIT_WORK(&req->f.work, nvmet_file_write_zeroes_work);
363 schedule_work(&req->f.work);
364}
365
366u16 nvmet_file_parse_io_cmd(struct nvmet_req *req)
367{
368 struct nvme_command *cmd = req->cmd;
369
370 switch (cmd->common.opcode) {
371 case nvme_cmd_read:
372 case nvme_cmd_write:
373 req->execute = nvmet_file_execute_rw;
374 req->data_len = nvmet_rw_len(req);
375 return 0;
376 case nvme_cmd_flush:
377 req->execute = nvmet_file_execute_flush;
378 req->data_len = 0;
379 return 0;
380 case nvme_cmd_dsm:
381 req->execute = nvmet_file_execute_dsm;
382 req->data_len = (le32_to_cpu(cmd->dsm.nr) + 1) *
383 sizeof(struct nvme_dsm_range);
384 return 0;
385 case nvme_cmd_write_zeroes:
386 req->execute = nvmet_file_execute_write_zeroes;
387 req->data_len = 0;
388 return 0;
389 default:
390 pr_err("unhandled cmd for file ns %d on qid %d\n",
391 cmd->common.opcode, req->sq->qid);
392 req->error_loc = offsetof(struct nvme_common_command, opcode);
393 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
394 }
395}
396
