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a62a8ef9 SH |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* | |
3 | * virtio-fs: Virtio Filesystem | |
4 | * Copyright (C) 2018 Red Hat, Inc. | |
5 | */ | |
6 | ||
7 | #include <linux/fs.h> | |
22f3787e SH |
8 | #include <linux/dax.h> |
9 | #include <linux/pci.h> | |
10 | #include <linux/pfn_t.h> | |
dc90f084 | 11 | #include <linux/memremap.h> |
a62a8ef9 SH |
12 | #include <linux/module.h> |
13 | #include <linux/virtio.h> | |
14 | #include <linux/virtio_fs.h> | |
15 | #include <linux/delay.h> | |
16 | #include <linux/fs_context.h> | |
1dd53957 | 17 | #include <linux/fs_parser.h> |
a62a8ef9 | 18 | #include <linux/highmem.h> |
562ce828 | 19 | #include <linux/cleanup.h> |
22f3787e | 20 | #include <linux/uio.h> |
a62a8ef9 SH |
21 | #include "fuse_i.h" |
22 | ||
a7f0d7aa CK |
23 | /* Used to help calculate the FUSE connection's max_pages limit for a request's |
24 | * size. Parts of the struct fuse_req are sliced into scattergather lists in | |
25 | * addition to the pages used, so this can help account for that overhead. | |
26 | */ | |
27 | #define FUSE_HEADER_OVERHEAD 4 | |
28 | ||
a62a8ef9 SH |
29 | /* List of virtio-fs device instances and a lock for the list. Also provides |
30 | * mutual exclusion in device removal and mounting path | |
31 | */ | |
32 | static DEFINE_MUTEX(virtio_fs_mutex); | |
33 | static LIST_HEAD(virtio_fs_instances); | |
34 | ||
a8f62f50 SH |
35 | /* The /sys/fs/virtio_fs/ kset */ |
36 | static struct kset *virtio_fs_kset; | |
37 | ||
a62a8ef9 SH |
38 | enum { |
39 | VQ_HIPRIO, | |
40 | VQ_REQUEST | |
41 | }; | |
42 | ||
b43b7e81 VG |
43 | #define VQ_NAME_LEN 24 |
44 | ||
a62a8ef9 SH |
45 | /* Per-virtqueue state */ |
46 | struct virtio_fs_vq { | |
47 | spinlock_t lock; | |
48 | struct virtqueue *vq; /* protected by ->lock */ | |
49 | struct work_struct done_work; | |
50 | struct list_head queued_reqs; | |
51fecdd2 | 51 | struct list_head end_reqs; /* End these requests */ |
a62a8ef9 SH |
52 | struct delayed_work dispatch_work; |
53 | struct fuse_dev *fud; | |
54 | bool connected; | |
55 | long in_flight; | |
724c15a4 | 56 | struct completion in_flight_zero; /* No inflight requests */ |
b43b7e81 | 57 | char name[VQ_NAME_LEN]; |
a62a8ef9 SH |
58 | } ____cacheline_aligned_in_smp; |
59 | ||
60 | /* A virtio-fs device instance */ | |
61 | struct virtio_fs { | |
a8f62f50 | 62 | struct kobject kobj; |
a62a8ef9 SH |
63 | struct list_head list; /* on virtio_fs_instances */ |
64 | char *tag; | |
65 | struct virtio_fs_vq *vqs; | |
66 | unsigned int nvqs; /* number of virtqueues */ | |
67 | unsigned int num_request_queues; /* number of request queues */ | |
22f3787e SH |
68 | struct dax_device *dax_dev; |
69 | ||
70 | /* DAX memory window where file contents are mapped */ | |
71 | void *window_kaddr; | |
72 | phys_addr_t window_phys_addr; | |
73 | size_t window_len; | |
a62a8ef9 SH |
74 | }; |
75 | ||
1efcf39e | 76 | struct virtio_fs_forget_req { |
a62a8ef9 SH |
77 | struct fuse_in_header ih; |
78 | struct fuse_forget_in arg; | |
1efcf39e VG |
79 | }; |
80 | ||
81 | struct virtio_fs_forget { | |
a62a8ef9 SH |
82 | /* This request can be temporarily queued on virt queue */ |
83 | struct list_head list; | |
1efcf39e | 84 | struct virtio_fs_forget_req req; |
a62a8ef9 SH |
85 | }; |
86 | ||
bb737bbe VG |
87 | struct virtio_fs_req_work { |
88 | struct fuse_req *req; | |
89 | struct virtio_fs_vq *fsvq; | |
90 | struct work_struct done_work; | |
91 | }; | |
92 | ||
a9bfd9dd VG |
93 | static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq, |
94 | struct fuse_req *req, bool in_flight); | |
95 | ||
780b1b95 JX |
96 | static const struct constant_table dax_param_enums[] = { |
97 | {"always", FUSE_DAX_ALWAYS }, | |
98 | {"never", FUSE_DAX_NEVER }, | |
99 | {"inode", FUSE_DAX_INODE_USER }, | |
100 | {} | |
101 | }; | |
102 | ||
1dd53957 VG |
103 | enum { |
104 | OPT_DAX, | |
780b1b95 | 105 | OPT_DAX_ENUM, |
1dd53957 VG |
106 | }; |
107 | ||
108 | static const struct fs_parameter_spec virtio_fs_parameters[] = { | |
109 | fsparam_flag("dax", OPT_DAX), | |
780b1b95 | 110 | fsparam_enum("dax", OPT_DAX_ENUM, dax_param_enums), |
1dd53957 VG |
111 | {} |
112 | }; | |
113 | ||
84c21507 | 114 | static int virtio_fs_parse_param(struct fs_context *fsc, |
1dd53957 VG |
115 | struct fs_parameter *param) |
116 | { | |
117 | struct fs_parse_result result; | |
84c21507 | 118 | struct fuse_fs_context *ctx = fsc->fs_private; |
1dd53957 VG |
119 | int opt; |
120 | ||
84c21507 | 121 | opt = fs_parse(fsc, virtio_fs_parameters, param, &result); |
1dd53957 VG |
122 | if (opt < 0) |
123 | return opt; | |
124 | ||
125 | switch (opt) { | |
126 | case OPT_DAX: | |
780b1b95 JX |
127 | ctx->dax_mode = FUSE_DAX_ALWAYS; |
128 | break; | |
129 | case OPT_DAX_ENUM: | |
130 | ctx->dax_mode = result.uint_32; | |
1dd53957 VG |
131 | break; |
132 | default: | |
133 | return -EINVAL; | |
134 | } | |
135 | ||
136 | return 0; | |
137 | } | |
138 | ||
84c21507 | 139 | static void virtio_fs_free_fsc(struct fs_context *fsc) |
1dd53957 | 140 | { |
84c21507 | 141 | struct fuse_fs_context *ctx = fsc->fs_private; |
1dd53957 VG |
142 | |
143 | kfree(ctx); | |
144 | } | |
145 | ||
a62a8ef9 SH |
146 | static inline struct virtio_fs_vq *vq_to_fsvq(struct virtqueue *vq) |
147 | { | |
148 | struct virtio_fs *fs = vq->vdev->priv; | |
149 | ||
150 | return &fs->vqs[vq->index]; | |
151 | } | |
152 | ||
c17ea009 VG |
153 | /* Should be called with fsvq->lock held. */ |
154 | static inline void inc_in_flight_req(struct virtio_fs_vq *fsvq) | |
155 | { | |
156 | fsvq->in_flight++; | |
157 | } | |
158 | ||
159 | /* Should be called with fsvq->lock held. */ | |
160 | static inline void dec_in_flight_req(struct virtio_fs_vq *fsvq) | |
161 | { | |
162 | WARN_ON(fsvq->in_flight <= 0); | |
163 | fsvq->in_flight--; | |
724c15a4 VG |
164 | if (!fsvq->in_flight) |
165 | complete(&fsvq->in_flight_zero); | |
c17ea009 VG |
166 | } |
167 | ||
a8f62f50 SH |
168 | static ssize_t tag_show(struct kobject *kobj, |
169 | struct kobj_attribute *attr, char *buf) | |
170 | { | |
171 | struct virtio_fs *fs = container_of(kobj, struct virtio_fs, kobj); | |
172 | ||
173 | return sysfs_emit(buf, fs->tag); | |
174 | } | |
175 | ||
176 | static struct kobj_attribute virtio_fs_tag_attr = __ATTR_RO(tag); | |
177 | ||
178 | static struct attribute *virtio_fs_attrs[] = { | |
179 | &virtio_fs_tag_attr.attr, | |
180 | NULL | |
181 | }; | |
182 | ATTRIBUTE_GROUPS(virtio_fs); | |
183 | ||
184 | static void virtio_fs_ktype_release(struct kobject *kobj) | |
a62a8ef9 | 185 | { |
a8f62f50 | 186 | struct virtio_fs *vfs = container_of(kobj, struct virtio_fs, kobj); |
a62a8ef9 SH |
187 | |
188 | kfree(vfs->vqs); | |
189 | kfree(vfs); | |
190 | } | |
191 | ||
a8f62f50 SH |
192 | static const struct kobj_type virtio_fs_ktype = { |
193 | .release = virtio_fs_ktype_release, | |
194 | .sysfs_ops = &kobj_sysfs_ops, | |
195 | .default_groups = virtio_fs_groups, | |
196 | }; | |
197 | ||
a62a8ef9 SH |
198 | /* Make sure virtiofs_mutex is held */ |
199 | static void virtio_fs_put(struct virtio_fs *fs) | |
200 | { | |
a8f62f50 | 201 | kobject_put(&fs->kobj); |
a62a8ef9 SH |
202 | } |
203 | ||
204 | static void virtio_fs_fiq_release(struct fuse_iqueue *fiq) | |
205 | { | |
206 | struct virtio_fs *vfs = fiq->priv; | |
207 | ||
208 | mutex_lock(&virtio_fs_mutex); | |
209 | virtio_fs_put(vfs); | |
210 | mutex_unlock(&virtio_fs_mutex); | |
211 | } | |
212 | ||
213 | static void virtio_fs_drain_queue(struct virtio_fs_vq *fsvq) | |
214 | { | |
215 | WARN_ON(fsvq->in_flight < 0); | |
216 | ||
217 | /* Wait for in flight requests to finish.*/ | |
724c15a4 VG |
218 | spin_lock(&fsvq->lock); |
219 | if (fsvq->in_flight) { | |
220 | /* We are holding virtio_fs_mutex. There should not be any | |
221 | * waiters waiting for completion. | |
222 | */ | |
223 | reinit_completion(&fsvq->in_flight_zero); | |
224 | spin_unlock(&fsvq->lock); | |
225 | wait_for_completion(&fsvq->in_flight_zero); | |
226 | } else { | |
a62a8ef9 | 227 | spin_unlock(&fsvq->lock); |
a62a8ef9 SH |
228 | } |
229 | ||
230 | flush_work(&fsvq->done_work); | |
231 | flush_delayed_work(&fsvq->dispatch_work); | |
232 | } | |
233 | ||
724c15a4 | 234 | static void virtio_fs_drain_all_queues_locked(struct virtio_fs *fs) |
a62a8ef9 SH |
235 | { |
236 | struct virtio_fs_vq *fsvq; | |
237 | int i; | |
238 | ||
239 | for (i = 0; i < fs->nvqs; i++) { | |
240 | fsvq = &fs->vqs[i]; | |
a62a8ef9 SH |
241 | virtio_fs_drain_queue(fsvq); |
242 | } | |
243 | } | |
244 | ||
724c15a4 VG |
245 | static void virtio_fs_drain_all_queues(struct virtio_fs *fs) |
246 | { | |
247 | /* Provides mutual exclusion between ->remove and ->kill_sb | |
248 | * paths. We don't want both of these draining queue at the | |
249 | * same time. Current completion logic reinits completion | |
250 | * and that means there should not be any other thread | |
251 | * doing reinit or waiting for completion already. | |
252 | */ | |
253 | mutex_lock(&virtio_fs_mutex); | |
254 | virtio_fs_drain_all_queues_locked(fs); | |
255 | mutex_unlock(&virtio_fs_mutex); | |
256 | } | |
257 | ||
a62a8ef9 SH |
258 | static void virtio_fs_start_all_queues(struct virtio_fs *fs) |
259 | { | |
260 | struct virtio_fs_vq *fsvq; | |
261 | int i; | |
262 | ||
263 | for (i = 0; i < fs->nvqs; i++) { | |
264 | fsvq = &fs->vqs[i]; | |
265 | spin_lock(&fsvq->lock); | |
266 | fsvq->connected = true; | |
267 | spin_unlock(&fsvq->lock); | |
268 | } | |
269 | } | |
270 | ||
271 | /* Add a new instance to the list or return -EEXIST if tag name exists*/ | |
a8f62f50 SH |
272 | static int virtio_fs_add_instance(struct virtio_device *vdev, |
273 | struct virtio_fs *fs) | |
a62a8ef9 SH |
274 | { |
275 | struct virtio_fs *fs2; | |
a8f62f50 | 276 | int ret; |
a62a8ef9 SH |
277 | |
278 | mutex_lock(&virtio_fs_mutex); | |
279 | ||
280 | list_for_each_entry(fs2, &virtio_fs_instances, list) { | |
a8f62f50 SH |
281 | if (strcmp(fs->tag, fs2->tag) == 0) { |
282 | mutex_unlock(&virtio_fs_mutex); | |
283 | return -EEXIST; | |
284 | } | |
a62a8ef9 SH |
285 | } |
286 | ||
a8f62f50 SH |
287 | /* Use the virtio_device's index as a unique identifier, there is no |
288 | * need to allocate our own identifiers because the virtio_fs instance | |
289 | * is only visible to userspace as long as the underlying virtio_device | |
290 | * exists. | |
291 | */ | |
292 | fs->kobj.kset = virtio_fs_kset; | |
293 | ret = kobject_add(&fs->kobj, NULL, "%d", vdev->index); | |
294 | if (ret < 0) { | |
295 | mutex_unlock(&virtio_fs_mutex); | |
296 | return ret; | |
297 | } | |
298 | ||
299 | ret = sysfs_create_link(&fs->kobj, &vdev->dev.kobj, "device"); | |
300 | if (ret < 0) { | |
301 | kobject_del(&fs->kobj); | |
302 | mutex_unlock(&virtio_fs_mutex); | |
303 | return ret; | |
a62a8ef9 SH |
304 | } |
305 | ||
a8f62f50 | 306 | list_add_tail(&fs->list, &virtio_fs_instances); |
a62a8ef9 SH |
307 | |
308 | mutex_unlock(&virtio_fs_mutex); | |
309 | ||
9086b2d9 SH |
310 | kobject_uevent(&fs->kobj, KOBJ_ADD); |
311 | ||
a62a8ef9 SH |
312 | return 0; |
313 | } | |
314 | ||
315 | /* Return the virtio_fs with a given tag, or NULL */ | |
316 | static struct virtio_fs *virtio_fs_find_instance(const char *tag) | |
317 | { | |
318 | struct virtio_fs *fs; | |
319 | ||
320 | mutex_lock(&virtio_fs_mutex); | |
321 | ||
322 | list_for_each_entry(fs, &virtio_fs_instances, list) { | |
323 | if (strcmp(fs->tag, tag) == 0) { | |
a8f62f50 | 324 | kobject_get(&fs->kobj); |
a62a8ef9 SH |
325 | goto found; |
326 | } | |
327 | } | |
328 | ||
329 | fs = NULL; /* not found */ | |
330 | ||
331 | found: | |
332 | mutex_unlock(&virtio_fs_mutex); | |
333 | ||
334 | return fs; | |
335 | } | |
336 | ||
337 | static void virtio_fs_free_devs(struct virtio_fs *fs) | |
338 | { | |
339 | unsigned int i; | |
340 | ||
341 | for (i = 0; i < fs->nvqs; i++) { | |
342 | struct virtio_fs_vq *fsvq = &fs->vqs[i]; | |
343 | ||
344 | if (!fsvq->fud) | |
345 | continue; | |
346 | ||
347 | fuse_dev_free(fsvq->fud); | |
348 | fsvq->fud = NULL; | |
349 | } | |
350 | } | |
351 | ||
352 | /* Read filesystem name from virtio config into fs->tag (must kfree()). */ | |
353 | static int virtio_fs_read_tag(struct virtio_device *vdev, struct virtio_fs *fs) | |
354 | { | |
355 | char tag_buf[sizeof_field(struct virtio_fs_config, tag)]; | |
356 | char *end; | |
357 | size_t len; | |
358 | ||
359 | virtio_cread_bytes(vdev, offsetof(struct virtio_fs_config, tag), | |
360 | &tag_buf, sizeof(tag_buf)); | |
361 | end = memchr(tag_buf, '\0', sizeof(tag_buf)); | |
362 | if (end == tag_buf) | |
363 | return -EINVAL; /* empty tag */ | |
364 | if (!end) | |
365 | end = &tag_buf[sizeof(tag_buf)]; | |
366 | ||
367 | len = end - tag_buf; | |
368 | fs->tag = devm_kmalloc(&vdev->dev, len + 1, GFP_KERNEL); | |
369 | if (!fs->tag) | |
370 | return -ENOMEM; | |
371 | memcpy(fs->tag, tag_buf, len); | |
372 | fs->tag[len] = '\0'; | |
40488cc1 SH |
373 | |
374 | /* While the VIRTIO specification allows any character, newlines are | |
375 | * awkward on mount(8) command-lines and cause problems in the sysfs | |
376 | * "tag" attr and uevent TAG= properties. Forbid them. | |
377 | */ | |
378 | if (strchr(fs->tag, '\n')) { | |
379 | dev_dbg(&vdev->dev, "refusing virtiofs tag with newline character\n"); | |
380 | return -EINVAL; | |
381 | } | |
382 | ||
a62a8ef9 SH |
383 | return 0; |
384 | } | |
385 | ||
386 | /* Work function for hiprio completion */ | |
387 | static void virtio_fs_hiprio_done_work(struct work_struct *work) | |
388 | { | |
389 | struct virtio_fs_vq *fsvq = container_of(work, struct virtio_fs_vq, | |
390 | done_work); | |
391 | struct virtqueue *vq = fsvq->vq; | |
392 | ||
393 | /* Free completed FUSE_FORGET requests */ | |
394 | spin_lock(&fsvq->lock); | |
395 | do { | |
396 | unsigned int len; | |
397 | void *req; | |
398 | ||
399 | virtqueue_disable_cb(vq); | |
400 | ||
401 | while ((req = virtqueue_get_buf(vq, &len)) != NULL) { | |
402 | kfree(req); | |
c17ea009 | 403 | dec_in_flight_req(fsvq); |
a62a8ef9 | 404 | } |
f9c29137 | 405 | } while (!virtqueue_enable_cb(vq)); |
a62a8ef9 SH |
406 | spin_unlock(&fsvq->lock); |
407 | } | |
408 | ||
51fecdd2 | 409 | static void virtio_fs_request_dispatch_work(struct work_struct *work) |
a62a8ef9 | 410 | { |
51fecdd2 VG |
411 | struct fuse_req *req; |
412 | struct virtio_fs_vq *fsvq = container_of(work, struct virtio_fs_vq, | |
413 | dispatch_work.work); | |
a9bfd9dd | 414 | int ret; |
51fecdd2 VG |
415 | |
416 | pr_debug("virtio-fs: worker %s called.\n", __func__); | |
417 | while (1) { | |
418 | spin_lock(&fsvq->lock); | |
419 | req = list_first_entry_or_null(&fsvq->end_reqs, struct fuse_req, | |
420 | list); | |
421 | if (!req) { | |
422 | spin_unlock(&fsvq->lock); | |
a9bfd9dd | 423 | break; |
51fecdd2 VG |
424 | } |
425 | ||
426 | list_del_init(&req->list); | |
427 | spin_unlock(&fsvq->lock); | |
8f622e94 | 428 | fuse_request_end(req); |
51fecdd2 | 429 | } |
a9bfd9dd VG |
430 | |
431 | /* Dispatch pending requests */ | |
432 | while (1) { | |
433 | spin_lock(&fsvq->lock); | |
434 | req = list_first_entry_or_null(&fsvq->queued_reqs, | |
435 | struct fuse_req, list); | |
436 | if (!req) { | |
437 | spin_unlock(&fsvq->lock); | |
438 | return; | |
439 | } | |
440 | list_del_init(&req->list); | |
441 | spin_unlock(&fsvq->lock); | |
442 | ||
443 | ret = virtio_fs_enqueue_req(fsvq, req, true); | |
444 | if (ret < 0) { | |
445 | if (ret == -ENOMEM || ret == -ENOSPC) { | |
446 | spin_lock(&fsvq->lock); | |
447 | list_add_tail(&req->list, &fsvq->queued_reqs); | |
448 | schedule_delayed_work(&fsvq->dispatch_work, | |
449 | msecs_to_jiffies(1)); | |
450 | spin_unlock(&fsvq->lock); | |
451 | return; | |
452 | } | |
453 | req->out.h.error = ret; | |
454 | spin_lock(&fsvq->lock); | |
455 | dec_in_flight_req(fsvq); | |
456 | spin_unlock(&fsvq->lock); | |
457 | pr_err("virtio-fs: virtio_fs_enqueue_req() failed %d\n", | |
458 | ret); | |
8f622e94 | 459 | fuse_request_end(req); |
a9bfd9dd VG |
460 | } |
461 | } | |
a62a8ef9 SH |
462 | } |
463 | ||
58ada94f VG |
464 | /* |
465 | * Returns 1 if queue is full and sender should wait a bit before sending | |
466 | * next request, 0 otherwise. | |
467 | */ | |
468 | static int send_forget_request(struct virtio_fs_vq *fsvq, | |
469 | struct virtio_fs_forget *forget, | |
470 | bool in_flight) | |
471 | { | |
472 | struct scatterlist sg; | |
473 | struct virtqueue *vq; | |
474 | int ret = 0; | |
475 | bool notify; | |
1efcf39e | 476 | struct virtio_fs_forget_req *req = &forget->req; |
58ada94f VG |
477 | |
478 | spin_lock(&fsvq->lock); | |
479 | if (!fsvq->connected) { | |
480 | if (in_flight) | |
481 | dec_in_flight_req(fsvq); | |
482 | kfree(forget); | |
483 | goto out; | |
484 | } | |
485 | ||
1efcf39e | 486 | sg_init_one(&sg, req, sizeof(*req)); |
58ada94f VG |
487 | vq = fsvq->vq; |
488 | dev_dbg(&vq->vdev->dev, "%s\n", __func__); | |
489 | ||
490 | ret = virtqueue_add_outbuf(vq, &sg, 1, forget, GFP_ATOMIC); | |
491 | if (ret < 0) { | |
492 | if (ret == -ENOMEM || ret == -ENOSPC) { | |
493 | pr_debug("virtio-fs: Could not queue FORGET: err=%d. Will try later\n", | |
494 | ret); | |
495 | list_add_tail(&forget->list, &fsvq->queued_reqs); | |
496 | schedule_delayed_work(&fsvq->dispatch_work, | |
497 | msecs_to_jiffies(1)); | |
498 | if (!in_flight) | |
499 | inc_in_flight_req(fsvq); | |
500 | /* Queue is full */ | |
501 | ret = 1; | |
502 | } else { | |
503 | pr_debug("virtio-fs: Could not queue FORGET: err=%d. Dropping it.\n", | |
504 | ret); | |
505 | kfree(forget); | |
506 | if (in_flight) | |
507 | dec_in_flight_req(fsvq); | |
508 | } | |
509 | goto out; | |
510 | } | |
511 | ||
512 | if (!in_flight) | |
513 | inc_in_flight_req(fsvq); | |
514 | notify = virtqueue_kick_prepare(vq); | |
515 | spin_unlock(&fsvq->lock); | |
516 | ||
517 | if (notify) | |
518 | virtqueue_notify(vq); | |
519 | return ret; | |
520 | out: | |
521 | spin_unlock(&fsvq->lock); | |
522 | return ret; | |
523 | } | |
524 | ||
a62a8ef9 SH |
525 | static void virtio_fs_hiprio_dispatch_work(struct work_struct *work) |
526 | { | |
527 | struct virtio_fs_forget *forget; | |
528 | struct virtio_fs_vq *fsvq = container_of(work, struct virtio_fs_vq, | |
529 | dispatch_work.work); | |
a62a8ef9 SH |
530 | pr_debug("virtio-fs: worker %s called.\n", __func__); |
531 | while (1) { | |
532 | spin_lock(&fsvq->lock); | |
533 | forget = list_first_entry_or_null(&fsvq->queued_reqs, | |
534 | struct virtio_fs_forget, list); | |
535 | if (!forget) { | |
536 | spin_unlock(&fsvq->lock); | |
537 | return; | |
538 | } | |
539 | ||
540 | list_del(&forget->list); | |
a62a8ef9 | 541 | spin_unlock(&fsvq->lock); |
58ada94f VG |
542 | if (send_forget_request(fsvq, forget, true)) |
543 | return; | |
a62a8ef9 SH |
544 | } |
545 | } | |
546 | ||
547 | /* Allocate and copy args into req->argbuf */ | |
548 | static int copy_args_to_argbuf(struct fuse_req *req) | |
549 | { | |
550 | struct fuse_args *args = req->args; | |
551 | unsigned int offset = 0; | |
552 | unsigned int num_in; | |
553 | unsigned int num_out; | |
554 | unsigned int len; | |
555 | unsigned int i; | |
556 | ||
557 | num_in = args->in_numargs - args->in_pages; | |
558 | num_out = args->out_numargs - args->out_pages; | |
559 | len = fuse_len_args(num_in, (struct fuse_arg *) args->in_args) + | |
560 | fuse_len_args(num_out, args->out_args); | |
561 | ||
562 | req->argbuf = kmalloc(len, GFP_ATOMIC); | |
563 | if (!req->argbuf) | |
564 | return -ENOMEM; | |
565 | ||
566 | for (i = 0; i < num_in; i++) { | |
567 | memcpy(req->argbuf + offset, | |
568 | args->in_args[i].value, | |
569 | args->in_args[i].size); | |
570 | offset += args->in_args[i].size; | |
571 | } | |
572 | ||
573 | return 0; | |
574 | } | |
575 | ||
576 | /* Copy args out of and free req->argbuf */ | |
577 | static void copy_args_from_argbuf(struct fuse_args *args, struct fuse_req *req) | |
578 | { | |
579 | unsigned int remaining; | |
580 | unsigned int offset; | |
581 | unsigned int num_in; | |
582 | unsigned int num_out; | |
583 | unsigned int i; | |
584 | ||
585 | remaining = req->out.h.len - sizeof(req->out.h); | |
586 | num_in = args->in_numargs - args->in_pages; | |
587 | num_out = args->out_numargs - args->out_pages; | |
588 | offset = fuse_len_args(num_in, (struct fuse_arg *)args->in_args); | |
589 | ||
590 | for (i = 0; i < num_out; i++) { | |
591 | unsigned int argsize = args->out_args[i].size; | |
592 | ||
593 | if (args->out_argvar && | |
594 | i == args->out_numargs - 1 && | |
595 | argsize > remaining) { | |
596 | argsize = remaining; | |
597 | } | |
598 | ||
599 | memcpy(args->out_args[i].value, req->argbuf + offset, argsize); | |
600 | offset += argsize; | |
601 | ||
602 | if (i != args->out_numargs - 1) | |
603 | remaining -= argsize; | |
604 | } | |
605 | ||
606 | /* Store the actual size of the variable-length arg */ | |
607 | if (args->out_argvar) | |
608 | args->out_args[args->out_numargs - 1].size = remaining; | |
609 | ||
610 | kfree(req->argbuf); | |
611 | req->argbuf = NULL; | |
612 | } | |
613 | ||
614 | /* Work function for request completion */ | |
bb737bbe VG |
615 | static void virtio_fs_request_complete(struct fuse_req *req, |
616 | struct virtio_fs_vq *fsvq) | |
617 | { | |
618 | struct fuse_pqueue *fpq = &fsvq->fud->pq; | |
bb737bbe VG |
619 | struct fuse_args *args; |
620 | struct fuse_args_pages *ap; | |
621 | unsigned int len, i, thislen; | |
622 | struct page *page; | |
623 | ||
624 | /* | |
625 | * TODO verify that server properly follows FUSE protocol | |
626 | * (oh.uniq, oh.len) | |
627 | */ | |
628 | args = req->args; | |
629 | copy_args_from_argbuf(args, req); | |
630 | ||
631 | if (args->out_pages && args->page_zeroing) { | |
632 | len = args->out_args[args->out_numargs - 1].size; | |
633 | ap = container_of(args, typeof(*ap), args); | |
634 | for (i = 0; i < ap->num_pages; i++) { | |
635 | thislen = ap->descs[i].length; | |
636 | if (len < thislen) { | |
637 | WARN_ON(ap->descs[i].offset); | |
638 | page = ap->pages[i]; | |
639 | zero_user_segment(page, len, thislen); | |
640 | len = 0; | |
641 | } else { | |
642 | len -= thislen; | |
643 | } | |
644 | } | |
645 | } | |
646 | ||
647 | spin_lock(&fpq->lock); | |
648 | clear_bit(FR_SENT, &req->flags); | |
649 | spin_unlock(&fpq->lock); | |
650 | ||
8f622e94 | 651 | fuse_request_end(req); |
bb737bbe VG |
652 | spin_lock(&fsvq->lock); |
653 | dec_in_flight_req(fsvq); | |
654 | spin_unlock(&fsvq->lock); | |
655 | } | |
656 | ||
657 | static void virtio_fs_complete_req_work(struct work_struct *work) | |
658 | { | |
659 | struct virtio_fs_req_work *w = | |
660 | container_of(work, typeof(*w), done_work); | |
661 | ||
662 | virtio_fs_request_complete(w->req, w->fsvq); | |
663 | kfree(w); | |
664 | } | |
665 | ||
a62a8ef9 SH |
666 | static void virtio_fs_requests_done_work(struct work_struct *work) |
667 | { | |
668 | struct virtio_fs_vq *fsvq = container_of(work, struct virtio_fs_vq, | |
669 | done_work); | |
670 | struct fuse_pqueue *fpq = &fsvq->fud->pq; | |
a62a8ef9 SH |
671 | struct virtqueue *vq = fsvq->vq; |
672 | struct fuse_req *req; | |
a62a8ef9 | 673 | struct fuse_req *next; |
bb737bbe | 674 | unsigned int len; |
a62a8ef9 SH |
675 | LIST_HEAD(reqs); |
676 | ||
677 | /* Collect completed requests off the virtqueue */ | |
678 | spin_lock(&fsvq->lock); | |
679 | do { | |
680 | virtqueue_disable_cb(vq); | |
681 | ||
682 | while ((req = virtqueue_get_buf(vq, &len)) != NULL) { | |
683 | spin_lock(&fpq->lock); | |
684 | list_move_tail(&req->list, &reqs); | |
685 | spin_unlock(&fpq->lock); | |
686 | } | |
f9c29137 | 687 | } while (!virtqueue_enable_cb(vq)); |
a62a8ef9 SH |
688 | spin_unlock(&fsvq->lock); |
689 | ||
690 | /* End requests */ | |
691 | list_for_each_entry_safe(req, next, &reqs, list) { | |
a62a8ef9 | 692 | list_del_init(&req->list); |
a62a8ef9 | 693 | |
bb737bbe VG |
694 | /* blocking async request completes in a worker context */ |
695 | if (req->args->may_block) { | |
696 | struct virtio_fs_req_work *w; | |
697 | ||
698 | w = kzalloc(sizeof(*w), GFP_NOFS | __GFP_NOFAIL); | |
699 | INIT_WORK(&w->done_work, virtio_fs_complete_req_work); | |
700 | w->fsvq = fsvq; | |
701 | w->req = req; | |
702 | schedule_work(&w->done_work); | |
703 | } else { | |
704 | virtio_fs_request_complete(req, fsvq); | |
705 | } | |
a62a8ef9 SH |
706 | } |
707 | } | |
708 | ||
709 | /* Virtqueue interrupt handler */ | |
710 | static void virtio_fs_vq_done(struct virtqueue *vq) | |
711 | { | |
712 | struct virtio_fs_vq *fsvq = vq_to_fsvq(vq); | |
713 | ||
714 | dev_dbg(&vq->vdev->dev, "%s %s\n", __func__, fsvq->name); | |
715 | ||
716 | schedule_work(&fsvq->done_work); | |
717 | } | |
718 | ||
b43b7e81 VG |
719 | static void virtio_fs_init_vq(struct virtio_fs_vq *fsvq, char *name, |
720 | int vq_type) | |
721 | { | |
7c594bbd | 722 | strscpy(fsvq->name, name, VQ_NAME_LEN); |
b43b7e81 VG |
723 | spin_lock_init(&fsvq->lock); |
724 | INIT_LIST_HEAD(&fsvq->queued_reqs); | |
725 | INIT_LIST_HEAD(&fsvq->end_reqs); | |
726 | init_completion(&fsvq->in_flight_zero); | |
727 | ||
728 | if (vq_type == VQ_REQUEST) { | |
729 | INIT_WORK(&fsvq->done_work, virtio_fs_requests_done_work); | |
730 | INIT_DELAYED_WORK(&fsvq->dispatch_work, | |
731 | virtio_fs_request_dispatch_work); | |
732 | } else { | |
733 | INIT_WORK(&fsvq->done_work, virtio_fs_hiprio_done_work); | |
734 | INIT_DELAYED_WORK(&fsvq->dispatch_work, | |
735 | virtio_fs_hiprio_dispatch_work); | |
736 | } | |
737 | } | |
738 | ||
a62a8ef9 SH |
739 | /* Initialize virtqueues */ |
740 | static int virtio_fs_setup_vqs(struct virtio_device *vdev, | |
741 | struct virtio_fs *fs) | |
742 | { | |
743 | struct virtqueue **vqs; | |
744 | vq_callback_t **callbacks; | |
745 | const char **names; | |
746 | unsigned int i; | |
747 | int ret = 0; | |
748 | ||
2c0349ec MT |
749 | virtio_cread_le(vdev, struct virtio_fs_config, num_request_queues, |
750 | &fs->num_request_queues); | |
a62a8ef9 SH |
751 | if (fs->num_request_queues == 0) |
752 | return -EINVAL; | |
753 | ||
b43b7e81 | 754 | fs->nvqs = VQ_REQUEST + fs->num_request_queues; |
a62a8ef9 SH |
755 | fs->vqs = kcalloc(fs->nvqs, sizeof(fs->vqs[VQ_HIPRIO]), GFP_KERNEL); |
756 | if (!fs->vqs) | |
757 | return -ENOMEM; | |
758 | ||
759 | vqs = kmalloc_array(fs->nvqs, sizeof(vqs[VQ_HIPRIO]), GFP_KERNEL); | |
760 | callbacks = kmalloc_array(fs->nvqs, sizeof(callbacks[VQ_HIPRIO]), | |
761 | GFP_KERNEL); | |
762 | names = kmalloc_array(fs->nvqs, sizeof(names[VQ_HIPRIO]), GFP_KERNEL); | |
763 | if (!vqs || !callbacks || !names) { | |
764 | ret = -ENOMEM; | |
765 | goto out; | |
766 | } | |
767 | ||
b43b7e81 | 768 | /* Initialize the hiprio/forget request virtqueue */ |
a62a8ef9 | 769 | callbacks[VQ_HIPRIO] = virtio_fs_vq_done; |
b43b7e81 | 770 | virtio_fs_init_vq(&fs->vqs[VQ_HIPRIO], "hiprio", VQ_HIPRIO); |
a62a8ef9 | 771 | names[VQ_HIPRIO] = fs->vqs[VQ_HIPRIO].name; |
a62a8ef9 SH |
772 | |
773 | /* Initialize the requests virtqueues */ | |
774 | for (i = VQ_REQUEST; i < fs->nvqs; i++) { | |
b43b7e81 VG |
775 | char vq_name[VQ_NAME_LEN]; |
776 | ||
777 | snprintf(vq_name, VQ_NAME_LEN, "requests.%u", i - VQ_REQUEST); | |
778 | virtio_fs_init_vq(&fs->vqs[i], vq_name, VQ_REQUEST); | |
a62a8ef9 SH |
779 | callbacks[i] = virtio_fs_vq_done; |
780 | names[i] = fs->vqs[i].name; | |
781 | } | |
782 | ||
783 | ret = virtio_find_vqs(vdev, fs->nvqs, vqs, callbacks, names, NULL); | |
784 | if (ret < 0) | |
785 | goto out; | |
786 | ||
787 | for (i = 0; i < fs->nvqs; i++) | |
788 | fs->vqs[i].vq = vqs[i]; | |
789 | ||
790 | virtio_fs_start_all_queues(fs); | |
791 | out: | |
792 | kfree(names); | |
793 | kfree(callbacks); | |
794 | kfree(vqs); | |
795 | if (ret) | |
796 | kfree(fs->vqs); | |
797 | return ret; | |
798 | } | |
799 | ||
800 | /* Free virtqueues (device must already be reset) */ | |
1e5b9e04 | 801 | static void virtio_fs_cleanup_vqs(struct virtio_device *vdev) |
a62a8ef9 SH |
802 | { |
803 | vdev->config->del_vqs(vdev); | |
804 | } | |
805 | ||
22f3787e SH |
806 | /* Map a window offset to a page frame number. The window offset will have |
807 | * been produced by .iomap_begin(), which maps a file offset to a window | |
808 | * offset. | |
809 | */ | |
810 | static long virtio_fs_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, | |
e511c4a3 JC |
811 | long nr_pages, enum dax_access_mode mode, |
812 | void **kaddr, pfn_t *pfn) | |
22f3787e SH |
813 | { |
814 | struct virtio_fs *fs = dax_get_private(dax_dev); | |
815 | phys_addr_t offset = PFN_PHYS(pgoff); | |
73fb2c8b | 816 | size_t max_nr_pages = fs->window_len / PAGE_SIZE - pgoff; |
22f3787e SH |
817 | |
818 | if (kaddr) | |
819 | *kaddr = fs->window_kaddr + offset; | |
820 | if (pfn) | |
821 | *pfn = phys_to_pfn_t(fs->window_phys_addr + offset, | |
822 | PFN_DEV | PFN_MAP); | |
823 | return nr_pages > max_nr_pages ? max_nr_pages : nr_pages; | |
824 | } | |
825 | ||
22f3787e SH |
826 | static int virtio_fs_zero_page_range(struct dax_device *dax_dev, |
827 | pgoff_t pgoff, size_t nr_pages) | |
828 | { | |
829 | long rc; | |
830 | void *kaddr; | |
831 | ||
e511c4a3 JC |
832 | rc = dax_direct_access(dax_dev, pgoff, nr_pages, DAX_ACCESS, &kaddr, |
833 | NULL); | |
22f3787e | 834 | if (rc < 0) |
1ea7ca1b JC |
835 | return dax_mem2blk_err(rc); |
836 | ||
22f3787e SH |
837 | memset(kaddr, 0, nr_pages << PAGE_SHIFT); |
838 | dax_flush(dax_dev, kaddr, nr_pages << PAGE_SHIFT); | |
839 | return 0; | |
840 | } | |
841 | ||
842 | static const struct dax_operations virtio_fs_dax_ops = { | |
843 | .direct_access = virtio_fs_direct_access, | |
22f3787e SH |
844 | .zero_page_range = virtio_fs_zero_page_range, |
845 | }; | |
846 | ||
847 | static void virtio_fs_cleanup_dax(void *data) | |
848 | { | |
849 | struct dax_device *dax_dev = data; | |
850 | ||
851 | kill_dax(dax_dev); | |
852 | put_dax(dax_dev); | |
853 | } | |
854 | ||
562ce828 MD |
855 | DEFINE_FREE(cleanup_dax, struct dax_dev *, if (!IS_ERR_OR_NULL(_T)) virtio_fs_cleanup_dax(_T)) |
856 | ||
22f3787e SH |
857 | static int virtio_fs_setup_dax(struct virtio_device *vdev, struct virtio_fs *fs) |
858 | { | |
562ce828 | 859 | struct dax_device *dax_dev __free(cleanup_dax) = NULL; |
22f3787e SH |
860 | struct virtio_shm_region cache_reg; |
861 | struct dev_pagemap *pgmap; | |
862 | bool have_cache; | |
863 | ||
864 | if (!IS_ENABLED(CONFIG_FUSE_DAX)) | |
865 | return 0; | |
866 | ||
562ce828 MD |
867 | dax_dev = alloc_dax(fs, &virtio_fs_dax_ops); |
868 | if (IS_ERR(dax_dev)) { | |
869 | int rc = PTR_ERR(dax_dev); | |
870 | return rc == -EOPNOTSUPP ? 0 : rc; | |
871 | } | |
872 | ||
22f3787e SH |
873 | /* Get cache region */ |
874 | have_cache = virtio_get_shm_region(vdev, &cache_reg, | |
875 | (u8)VIRTIO_FS_SHMCAP_ID_CACHE); | |
876 | if (!have_cache) { | |
877 | dev_notice(&vdev->dev, "%s: No cache capability\n", __func__); | |
878 | return 0; | |
879 | } | |
880 | ||
881 | if (!devm_request_mem_region(&vdev->dev, cache_reg.addr, cache_reg.len, | |
882 | dev_name(&vdev->dev))) { | |
883 | dev_warn(&vdev->dev, "could not reserve region addr=0x%llx len=0x%llx\n", | |
884 | cache_reg.addr, cache_reg.len); | |
885 | return -EBUSY; | |
886 | } | |
887 | ||
888 | dev_notice(&vdev->dev, "Cache len: 0x%llx @ 0x%llx\n", cache_reg.len, | |
889 | cache_reg.addr); | |
890 | ||
891 | pgmap = devm_kzalloc(&vdev->dev, sizeof(*pgmap), GFP_KERNEL); | |
892 | if (!pgmap) | |
893 | return -ENOMEM; | |
894 | ||
895 | pgmap->type = MEMORY_DEVICE_FS_DAX; | |
896 | ||
897 | /* Ideally we would directly use the PCI BAR resource but | |
898 | * devm_memremap_pages() wants its own copy in pgmap. So | |
899 | * initialize a struct resource from scratch (only the start | |
900 | * and end fields will be used). | |
901 | */ | |
69456535 | 902 | pgmap->range = (struct range) { |
22f3787e SH |
903 | .start = (phys_addr_t) cache_reg.addr, |
904 | .end = (phys_addr_t) cache_reg.addr + cache_reg.len - 1, | |
905 | }; | |
69456535 | 906 | pgmap->nr_range = 1; |
22f3787e SH |
907 | |
908 | fs->window_kaddr = devm_memremap_pages(&vdev->dev, pgmap); | |
909 | if (IS_ERR(fs->window_kaddr)) | |
910 | return PTR_ERR(fs->window_kaddr); | |
911 | ||
912 | fs->window_phys_addr = (phys_addr_t) cache_reg.addr; | |
913 | fs->window_len = (phys_addr_t) cache_reg.len; | |
914 | ||
915 | dev_dbg(&vdev->dev, "%s: window kaddr 0x%px phys_addr 0x%llx len 0x%llx\n", | |
916 | __func__, fs->window_kaddr, cache_reg.addr, cache_reg.len); | |
917 | ||
562ce828 | 918 | fs->dax_dev = no_free_ptr(dax_dev); |
22f3787e SH |
919 | return devm_add_action_or_reset(&vdev->dev, virtio_fs_cleanup_dax, |
920 | fs->dax_dev); | |
921 | } | |
922 | ||
a62a8ef9 SH |
923 | static int virtio_fs_probe(struct virtio_device *vdev) |
924 | { | |
925 | struct virtio_fs *fs; | |
926 | int ret; | |
927 | ||
928 | fs = kzalloc(sizeof(*fs), GFP_KERNEL); | |
929 | if (!fs) | |
930 | return -ENOMEM; | |
a8f62f50 | 931 | kobject_init(&fs->kobj, &virtio_fs_ktype); |
a62a8ef9 SH |
932 | vdev->priv = fs; |
933 | ||
934 | ret = virtio_fs_read_tag(vdev, fs); | |
935 | if (ret < 0) | |
936 | goto out; | |
937 | ||
938 | ret = virtio_fs_setup_vqs(vdev, fs); | |
939 | if (ret < 0) | |
940 | goto out; | |
941 | ||
942 | /* TODO vq affinity */ | |
943 | ||
22f3787e SH |
944 | ret = virtio_fs_setup_dax(vdev, fs); |
945 | if (ret < 0) | |
946 | goto out_vqs; | |
947 | ||
a62a8ef9 SH |
948 | /* Bring the device online in case the filesystem is mounted and |
949 | * requests need to be sent before we return. | |
950 | */ | |
951 | virtio_device_ready(vdev); | |
952 | ||
a8f62f50 | 953 | ret = virtio_fs_add_instance(vdev, fs); |
a62a8ef9 SH |
954 | if (ret < 0) |
955 | goto out_vqs; | |
956 | ||
957 | return 0; | |
958 | ||
959 | out_vqs: | |
d9679d00 | 960 | virtio_reset_device(vdev); |
1e5b9e04 | 961 | virtio_fs_cleanup_vqs(vdev); |
a62a8ef9 SH |
962 | |
963 | out: | |
964 | vdev->priv = NULL; | |
a8f62f50 | 965 | kobject_put(&fs->kobj); |
a62a8ef9 SH |
966 | return ret; |
967 | } | |
968 | ||
969 | static void virtio_fs_stop_all_queues(struct virtio_fs *fs) | |
970 | { | |
971 | struct virtio_fs_vq *fsvq; | |
972 | int i; | |
973 | ||
974 | for (i = 0; i < fs->nvqs; i++) { | |
975 | fsvq = &fs->vqs[i]; | |
976 | spin_lock(&fsvq->lock); | |
977 | fsvq->connected = false; | |
978 | spin_unlock(&fsvq->lock); | |
979 | } | |
980 | } | |
981 | ||
982 | static void virtio_fs_remove(struct virtio_device *vdev) | |
983 | { | |
984 | struct virtio_fs *fs = vdev->priv; | |
985 | ||
986 | mutex_lock(&virtio_fs_mutex); | |
987 | /* This device is going away. No one should get new reference */ | |
988 | list_del_init(&fs->list); | |
a8f62f50 SH |
989 | sysfs_remove_link(&fs->kobj, "device"); |
990 | kobject_del(&fs->kobj); | |
a62a8ef9 | 991 | virtio_fs_stop_all_queues(fs); |
724c15a4 | 992 | virtio_fs_drain_all_queues_locked(fs); |
d9679d00 | 993 | virtio_reset_device(vdev); |
1e5b9e04 | 994 | virtio_fs_cleanup_vqs(vdev); |
a62a8ef9 SH |
995 | |
996 | vdev->priv = NULL; | |
997 | /* Put device reference on virtio_fs object */ | |
998 | virtio_fs_put(fs); | |
999 | mutex_unlock(&virtio_fs_mutex); | |
1000 | } | |
1001 | ||
1002 | #ifdef CONFIG_PM_SLEEP | |
1003 | static int virtio_fs_freeze(struct virtio_device *vdev) | |
1004 | { | |
1005 | /* TODO need to save state here */ | |
1006 | pr_warn("virtio-fs: suspend/resume not yet supported\n"); | |
1007 | return -EOPNOTSUPP; | |
1008 | } | |
1009 | ||
1010 | static int virtio_fs_restore(struct virtio_device *vdev) | |
1011 | { | |
1012 | /* TODO need to restore state here */ | |
1013 | return 0; | |
1014 | } | |
1015 | #endif /* CONFIG_PM_SLEEP */ | |
1016 | ||
00929447 | 1017 | static const struct virtio_device_id id_table[] = { |
a62a8ef9 SH |
1018 | { VIRTIO_ID_FS, VIRTIO_DEV_ANY_ID }, |
1019 | {}, | |
1020 | }; | |
1021 | ||
00929447 | 1022 | static const unsigned int feature_table[] = {}; |
a62a8ef9 SH |
1023 | |
1024 | static struct virtio_driver virtio_fs_driver = { | |
1025 | .driver.name = KBUILD_MODNAME, | |
1026 | .driver.owner = THIS_MODULE, | |
1027 | .id_table = id_table, | |
1028 | .feature_table = feature_table, | |
1029 | .feature_table_size = ARRAY_SIZE(feature_table), | |
1030 | .probe = virtio_fs_probe, | |
1031 | .remove = virtio_fs_remove, | |
1032 | #ifdef CONFIG_PM_SLEEP | |
1033 | .freeze = virtio_fs_freeze, | |
1034 | .restore = virtio_fs_restore, | |
1035 | #endif | |
1036 | }; | |
1037 | ||
1038 | static void virtio_fs_wake_forget_and_unlock(struct fuse_iqueue *fiq) | |
1039 | __releases(fiq->lock) | |
1040 | { | |
1041 | struct fuse_forget_link *link; | |
1042 | struct virtio_fs_forget *forget; | |
1efcf39e | 1043 | struct virtio_fs_forget_req *req; |
a62a8ef9 | 1044 | struct virtio_fs *fs; |
a62a8ef9 | 1045 | struct virtio_fs_vq *fsvq; |
a62a8ef9 | 1046 | u64 unique; |
a62a8ef9 SH |
1047 | |
1048 | link = fuse_dequeue_forget(fiq, 1, NULL); | |
1049 | unique = fuse_get_unique(fiq); | |
1050 | ||
1051 | fs = fiq->priv; | |
1052 | fsvq = &fs->vqs[VQ_HIPRIO]; | |
1053 | spin_unlock(&fiq->lock); | |
1054 | ||
1055 | /* Allocate a buffer for the request */ | |
1056 | forget = kmalloc(sizeof(*forget), GFP_NOFS | __GFP_NOFAIL); | |
1efcf39e | 1057 | req = &forget->req; |
a62a8ef9 | 1058 | |
1efcf39e | 1059 | req->ih = (struct fuse_in_header){ |
a62a8ef9 SH |
1060 | .opcode = FUSE_FORGET, |
1061 | .nodeid = link->forget_one.nodeid, | |
1062 | .unique = unique, | |
1efcf39e | 1063 | .len = sizeof(*req), |
a62a8ef9 | 1064 | }; |
1efcf39e | 1065 | req->arg = (struct fuse_forget_in){ |
a62a8ef9 SH |
1066 | .nlookup = link->forget_one.nlookup, |
1067 | }; | |
1068 | ||
58ada94f | 1069 | send_forget_request(fsvq, forget, false); |
a62a8ef9 SH |
1070 | kfree(link); |
1071 | } | |
1072 | ||
1073 | static void virtio_fs_wake_interrupt_and_unlock(struct fuse_iqueue *fiq) | |
1074 | __releases(fiq->lock) | |
1075 | { | |
1076 | /* | |
1077 | * TODO interrupts. | |
1078 | * | |
1079 | * Normal fs operations on a local filesystems aren't interruptible. | |
1080 | * Exceptions are blocking lock operations; for example fcntl(F_SETLKW) | |
1081 | * with shared lock between host and guest. | |
1082 | */ | |
1083 | spin_unlock(&fiq->lock); | |
1084 | } | |
1085 | ||
42d3e2d0 VG |
1086 | /* Count number of scatter-gather elements required */ |
1087 | static unsigned int sg_count_fuse_pages(struct fuse_page_desc *page_descs, | |
1088 | unsigned int num_pages, | |
1089 | unsigned int total_len) | |
1090 | { | |
1091 | unsigned int i; | |
1092 | unsigned int this_len; | |
1093 | ||
1094 | for (i = 0; i < num_pages && total_len; i++) { | |
1095 | this_len = min(page_descs[i].length, total_len); | |
1096 | total_len -= this_len; | |
1097 | } | |
1098 | ||
1099 | return i; | |
1100 | } | |
1101 | ||
a62a8ef9 SH |
1102 | /* Return the number of scatter-gather list elements required */ |
1103 | static unsigned int sg_count_fuse_req(struct fuse_req *req) | |
1104 | { | |
1105 | struct fuse_args *args = req->args; | |
1106 | struct fuse_args_pages *ap = container_of(args, typeof(*ap), args); | |
42d3e2d0 | 1107 | unsigned int size, total_sgs = 1 /* fuse_in_header */; |
a62a8ef9 SH |
1108 | |
1109 | if (args->in_numargs - args->in_pages) | |
1110 | total_sgs += 1; | |
1111 | ||
42d3e2d0 VG |
1112 | if (args->in_pages) { |
1113 | size = args->in_args[args->in_numargs - 1].size; | |
1114 | total_sgs += sg_count_fuse_pages(ap->descs, ap->num_pages, | |
1115 | size); | |
1116 | } | |
a62a8ef9 SH |
1117 | |
1118 | if (!test_bit(FR_ISREPLY, &req->flags)) | |
1119 | return total_sgs; | |
1120 | ||
1121 | total_sgs += 1 /* fuse_out_header */; | |
1122 | ||
1123 | if (args->out_numargs - args->out_pages) | |
1124 | total_sgs += 1; | |
1125 | ||
42d3e2d0 VG |
1126 | if (args->out_pages) { |
1127 | size = args->out_args[args->out_numargs - 1].size; | |
1128 | total_sgs += sg_count_fuse_pages(ap->descs, ap->num_pages, | |
1129 | size); | |
1130 | } | |
a62a8ef9 SH |
1131 | |
1132 | return total_sgs; | |
1133 | } | |
1134 | ||
1135 | /* Add pages to scatter-gather list and return number of elements used */ | |
1136 | static unsigned int sg_init_fuse_pages(struct scatterlist *sg, | |
1137 | struct page **pages, | |
1138 | struct fuse_page_desc *page_descs, | |
1139 | unsigned int num_pages, | |
1140 | unsigned int total_len) | |
1141 | { | |
1142 | unsigned int i; | |
1143 | unsigned int this_len; | |
1144 | ||
1145 | for (i = 0; i < num_pages && total_len; i++) { | |
1146 | sg_init_table(&sg[i], 1); | |
1147 | this_len = min(page_descs[i].length, total_len); | |
1148 | sg_set_page(&sg[i], pages[i], this_len, page_descs[i].offset); | |
1149 | total_len -= this_len; | |
1150 | } | |
1151 | ||
1152 | return i; | |
1153 | } | |
1154 | ||
1155 | /* Add args to scatter-gather list and return number of elements used */ | |
1156 | static unsigned int sg_init_fuse_args(struct scatterlist *sg, | |
1157 | struct fuse_req *req, | |
1158 | struct fuse_arg *args, | |
1159 | unsigned int numargs, | |
1160 | bool argpages, | |
1161 | void *argbuf, | |
1162 | unsigned int *len_used) | |
1163 | { | |
1164 | struct fuse_args_pages *ap = container_of(req->args, typeof(*ap), args); | |
1165 | unsigned int total_sgs = 0; | |
1166 | unsigned int len; | |
1167 | ||
1168 | len = fuse_len_args(numargs - argpages, args); | |
1169 | if (len) | |
1170 | sg_init_one(&sg[total_sgs++], argbuf, len); | |
1171 | ||
1172 | if (argpages) | |
1173 | total_sgs += sg_init_fuse_pages(&sg[total_sgs], | |
1174 | ap->pages, ap->descs, | |
1175 | ap->num_pages, | |
1176 | args[numargs - 1].size); | |
1177 | ||
1178 | if (len_used) | |
1179 | *len_used = len; | |
1180 | ||
1181 | return total_sgs; | |
1182 | } | |
1183 | ||
1184 | /* Add a request to a virtqueue and kick the device */ | |
1185 | static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq, | |
a9bfd9dd | 1186 | struct fuse_req *req, bool in_flight) |
a62a8ef9 SH |
1187 | { |
1188 | /* requests need at least 4 elements */ | |
1189 | struct scatterlist *stack_sgs[6]; | |
1190 | struct scatterlist stack_sg[ARRAY_SIZE(stack_sgs)]; | |
1191 | struct scatterlist **sgs = stack_sgs; | |
1192 | struct scatterlist *sg = stack_sg; | |
1193 | struct virtqueue *vq; | |
1194 | struct fuse_args *args = req->args; | |
1195 | unsigned int argbuf_used = 0; | |
1196 | unsigned int out_sgs = 0; | |
1197 | unsigned int in_sgs = 0; | |
1198 | unsigned int total_sgs; | |
1199 | unsigned int i; | |
1200 | int ret; | |
1201 | bool notify; | |
5dbe190f | 1202 | struct fuse_pqueue *fpq; |
a62a8ef9 SH |
1203 | |
1204 | /* Does the sglist fit on the stack? */ | |
1205 | total_sgs = sg_count_fuse_req(req); | |
1206 | if (total_sgs > ARRAY_SIZE(stack_sgs)) { | |
1207 | sgs = kmalloc_array(total_sgs, sizeof(sgs[0]), GFP_ATOMIC); | |
1208 | sg = kmalloc_array(total_sgs, sizeof(sg[0]), GFP_ATOMIC); | |
1209 | if (!sgs || !sg) { | |
1210 | ret = -ENOMEM; | |
1211 | goto out; | |
1212 | } | |
1213 | } | |
1214 | ||
1215 | /* Use a bounce buffer since stack args cannot be mapped */ | |
1216 | ret = copy_args_to_argbuf(req); | |
1217 | if (ret < 0) | |
1218 | goto out; | |
1219 | ||
1220 | /* Request elements */ | |
1221 | sg_init_one(&sg[out_sgs++], &req->in.h, sizeof(req->in.h)); | |
1222 | out_sgs += sg_init_fuse_args(&sg[out_sgs], req, | |
1223 | (struct fuse_arg *)args->in_args, | |
1224 | args->in_numargs, args->in_pages, | |
1225 | req->argbuf, &argbuf_used); | |
1226 | ||
1227 | /* Reply elements */ | |
1228 | if (test_bit(FR_ISREPLY, &req->flags)) { | |
1229 | sg_init_one(&sg[out_sgs + in_sgs++], | |
1230 | &req->out.h, sizeof(req->out.h)); | |
1231 | in_sgs += sg_init_fuse_args(&sg[out_sgs + in_sgs], req, | |
1232 | args->out_args, args->out_numargs, | |
1233 | args->out_pages, | |
1234 | req->argbuf + argbuf_used, NULL); | |
1235 | } | |
1236 | ||
1237 | WARN_ON(out_sgs + in_sgs != total_sgs); | |
1238 | ||
1239 | for (i = 0; i < total_sgs; i++) | |
1240 | sgs[i] = &sg[i]; | |
1241 | ||
1242 | spin_lock(&fsvq->lock); | |
1243 | ||
1244 | if (!fsvq->connected) { | |
1245 | spin_unlock(&fsvq->lock); | |
1246 | ret = -ENOTCONN; | |
1247 | goto out; | |
1248 | } | |
1249 | ||
1250 | vq = fsvq->vq; | |
1251 | ret = virtqueue_add_sgs(vq, sgs, out_sgs, in_sgs, req, GFP_ATOMIC); | |
1252 | if (ret < 0) { | |
1253 | spin_unlock(&fsvq->lock); | |
1254 | goto out; | |
1255 | } | |
1256 | ||
5dbe190f VG |
1257 | /* Request successfully sent. */ |
1258 | fpq = &fsvq->fud->pq; | |
1259 | spin_lock(&fpq->lock); | |
1260 | list_add_tail(&req->list, fpq->processing); | |
1261 | spin_unlock(&fpq->lock); | |
1262 | set_bit(FR_SENT, &req->flags); | |
1263 | /* matches barrier in request_wait_answer() */ | |
1264 | smp_mb__after_atomic(); | |
1265 | ||
a9bfd9dd VG |
1266 | if (!in_flight) |
1267 | inc_in_flight_req(fsvq); | |
a62a8ef9 SH |
1268 | notify = virtqueue_kick_prepare(vq); |
1269 | ||
1270 | spin_unlock(&fsvq->lock); | |
1271 | ||
1272 | if (notify) | |
1273 | virtqueue_notify(vq); | |
1274 | ||
1275 | out: | |
1276 | if (ret < 0 && req->argbuf) { | |
1277 | kfree(req->argbuf); | |
1278 | req->argbuf = NULL; | |
1279 | } | |
1280 | if (sgs != stack_sgs) { | |
1281 | kfree(sgs); | |
1282 | kfree(sg); | |
1283 | } | |
1284 | ||
1285 | return ret; | |
1286 | } | |
1287 | ||
1288 | static void virtio_fs_wake_pending_and_unlock(struct fuse_iqueue *fiq) | |
1289 | __releases(fiq->lock) | |
1290 | { | |
1291 | unsigned int queue_id = VQ_REQUEST; /* TODO multiqueue */ | |
1292 | struct virtio_fs *fs; | |
a62a8ef9 | 1293 | struct fuse_req *req; |
51fecdd2 | 1294 | struct virtio_fs_vq *fsvq; |
a62a8ef9 SH |
1295 | int ret; |
1296 | ||
1297 | WARN_ON(list_empty(&fiq->pending)); | |
1298 | req = list_last_entry(&fiq->pending, struct fuse_req, list); | |
1299 | clear_bit(FR_PENDING, &req->flags); | |
1300 | list_del_init(&req->list); | |
1301 | WARN_ON(!list_empty(&fiq->pending)); | |
1302 | spin_unlock(&fiq->lock); | |
1303 | ||
1304 | fs = fiq->priv; | |
a62a8ef9 SH |
1305 | |
1306 | pr_debug("%s: opcode %u unique %#llx nodeid %#llx in.len %u out.len %u\n", | |
1307 | __func__, req->in.h.opcode, req->in.h.unique, | |
1308 | req->in.h.nodeid, req->in.h.len, | |
1309 | fuse_len_args(req->args->out_numargs, req->args->out_args)); | |
1310 | ||
51fecdd2 | 1311 | fsvq = &fs->vqs[queue_id]; |
a9bfd9dd | 1312 | ret = virtio_fs_enqueue_req(fsvq, req, false); |
a62a8ef9 SH |
1313 | if (ret < 0) { |
1314 | if (ret == -ENOMEM || ret == -ENOSPC) { | |
a9bfd9dd VG |
1315 | /* |
1316 | * Virtqueue full. Retry submission from worker | |
1317 | * context as we might be holding fc->bg_lock. | |
1318 | */ | |
1319 | spin_lock(&fsvq->lock); | |
1320 | list_add_tail(&req->list, &fsvq->queued_reqs); | |
1321 | inc_in_flight_req(fsvq); | |
1322 | schedule_delayed_work(&fsvq->dispatch_work, | |
1323 | msecs_to_jiffies(1)); | |
1324 | spin_unlock(&fsvq->lock); | |
1325 | return; | |
a62a8ef9 SH |
1326 | } |
1327 | req->out.h.error = ret; | |
1328 | pr_err("virtio-fs: virtio_fs_enqueue_req() failed %d\n", ret); | |
51fecdd2 VG |
1329 | |
1330 | /* Can't end request in submission context. Use a worker */ | |
1331 | spin_lock(&fsvq->lock); | |
1332 | list_add_tail(&req->list, &fsvq->end_reqs); | |
1333 | schedule_delayed_work(&fsvq->dispatch_work, 0); | |
1334 | spin_unlock(&fsvq->lock); | |
a62a8ef9 SH |
1335 | return; |
1336 | } | |
1337 | } | |
1338 | ||
00929447 | 1339 | static const struct fuse_iqueue_ops virtio_fs_fiq_ops = { |
a62a8ef9 SH |
1340 | .wake_forget_and_unlock = virtio_fs_wake_forget_and_unlock, |
1341 | .wake_interrupt_and_unlock = virtio_fs_wake_interrupt_and_unlock, | |
1342 | .wake_pending_and_unlock = virtio_fs_wake_pending_and_unlock, | |
1343 | .release = virtio_fs_fiq_release, | |
1344 | }; | |
1345 | ||
1dd53957 | 1346 | static inline void virtio_fs_ctx_set_defaults(struct fuse_fs_context *ctx) |
a62a8ef9 | 1347 | { |
1dd53957 VG |
1348 | ctx->rootmode = S_IFDIR; |
1349 | ctx->default_permissions = 1; | |
1350 | ctx->allow_other = 1; | |
1351 | ctx->max_read = UINT_MAX; | |
1352 | ctx->blksize = 512; | |
1353 | ctx->destroy = true; | |
1354 | ctx->no_control = true; | |
1355 | ctx->no_force_umount = true; | |
1356 | } | |
1357 | ||
1358 | static int virtio_fs_fill_super(struct super_block *sb, struct fs_context *fsc) | |
a62a8ef9 | 1359 | { |
fcee216b MR |
1360 | struct fuse_mount *fm = get_fuse_mount_super(sb); |
1361 | struct fuse_conn *fc = fm->fc; | |
a62a8ef9 | 1362 | struct virtio_fs *fs = fc->iq.priv; |
1dd53957 | 1363 | struct fuse_fs_context *ctx = fsc->fs_private; |
a62a8ef9 SH |
1364 | unsigned int i; |
1365 | int err; | |
a62a8ef9 | 1366 | |
1dd53957 | 1367 | virtio_fs_ctx_set_defaults(ctx); |
a62a8ef9 SH |
1368 | mutex_lock(&virtio_fs_mutex); |
1369 | ||
1370 | /* After holding mutex, make sure virtiofs device is still there. | |
1371 | * Though we are holding a reference to it, drive ->remove might | |
1372 | * still have cleaned up virtual queues. In that case bail out. | |
1373 | */ | |
1374 | err = -EINVAL; | |
1375 | if (list_empty(&fs->list)) { | |
1376 | pr_info("virtio-fs: tag <%s> not found\n", fs->tag); | |
1377 | goto err; | |
1378 | } | |
1379 | ||
1380 | err = -ENOMEM; | |
1381 | /* Allocate fuse_dev for hiprio and notification queues */ | |
7fd3abfa | 1382 | for (i = 0; i < fs->nvqs; i++) { |
a62a8ef9 SH |
1383 | struct virtio_fs_vq *fsvq = &fs->vqs[i]; |
1384 | ||
1385 | fsvq->fud = fuse_dev_alloc(); | |
1386 | if (!fsvq->fud) | |
1387 | goto err_free_fuse_devs; | |
1388 | } | |
1389 | ||
7fd3abfa | 1390 | /* virtiofs allocates and installs its own fuse devices */ |
1dd53957 | 1391 | ctx->fudptr = NULL; |
780b1b95 JX |
1392 | if (ctx->dax_mode != FUSE_DAX_NEVER) { |
1393 | if (ctx->dax_mode == FUSE_DAX_ALWAYS && !fs->dax_dev) { | |
3f9b9efd VG |
1394 | err = -EINVAL; |
1395 | pr_err("virtio-fs: dax can't be enabled as filesystem" | |
1396 | " device does not support it.\n"); | |
1397 | goto err_free_fuse_devs; | |
1398 | } | |
1dd53957 | 1399 | ctx->dax_dev = fs->dax_dev; |
3f9b9efd | 1400 | } |
1dd53957 | 1401 | err = fuse_fill_super_common(sb, ctx); |
a62a8ef9 SH |
1402 | if (err < 0) |
1403 | goto err_free_fuse_devs; | |
1404 | ||
a62a8ef9 SH |
1405 | for (i = 0; i < fs->nvqs; i++) { |
1406 | struct virtio_fs_vq *fsvq = &fs->vqs[i]; | |
1407 | ||
a62a8ef9 SH |
1408 | fuse_dev_install(fsvq->fud, fc); |
1409 | } | |
1410 | ||
1411 | /* Previous unmount will stop all queues. Start these again */ | |
1412 | virtio_fs_start_all_queues(fs); | |
fcee216b | 1413 | fuse_send_init(fm); |
a62a8ef9 SH |
1414 | mutex_unlock(&virtio_fs_mutex); |
1415 | return 0; | |
1416 | ||
1417 | err_free_fuse_devs: | |
1418 | virtio_fs_free_devs(fs); | |
1419 | err: | |
1420 | mutex_unlock(&virtio_fs_mutex); | |
1421 | return err; | |
1422 | } | |
1423 | ||
fcee216b | 1424 | static void virtio_fs_conn_destroy(struct fuse_mount *fm) |
a62a8ef9 | 1425 | { |
fcee216b MR |
1426 | struct fuse_conn *fc = fm->fc; |
1427 | struct virtio_fs *vfs = fc->iq.priv; | |
1428 | struct virtio_fs_vq *fsvq = &vfs->vqs[VQ_HIPRIO]; | |
a62a8ef9 | 1429 | |
fcee216b MR |
1430 | /* Stop dax worker. Soon evict_inodes() will be called which |
1431 | * will free all memory ranges belonging to all inodes. | |
9a752d18 VG |
1432 | */ |
1433 | if (IS_ENABLED(CONFIG_FUSE_DAX)) | |
1434 | fuse_dax_cancel_work(fc); | |
a62a8ef9 SH |
1435 | |
1436 | /* Stop forget queue. Soon destroy will be sent */ | |
1437 | spin_lock(&fsvq->lock); | |
1438 | fsvq->connected = false; | |
1439 | spin_unlock(&fsvq->lock); | |
1440 | virtio_fs_drain_all_queues(vfs); | |
1441 | ||
fcee216b | 1442 | fuse_conn_destroy(fm); |
a62a8ef9 | 1443 | |
fcee216b | 1444 | /* fuse_conn_destroy() must have sent destroy. Stop all queues |
a62a8ef9 SH |
1445 | * and drain one more time and free fuse devices. Freeing fuse |
1446 | * devices will drop their reference on fuse_conn and that in | |
1447 | * turn will drop its reference on virtio_fs object. | |
1448 | */ | |
1449 | virtio_fs_stop_all_queues(vfs); | |
1450 | virtio_fs_drain_all_queues(vfs); | |
1451 | virtio_fs_free_devs(vfs); | |
1452 | } | |
1453 | ||
fcee216b MR |
1454 | static void virtio_kill_sb(struct super_block *sb) |
1455 | { | |
1456 | struct fuse_mount *fm = get_fuse_mount_super(sb); | |
1457 | bool last; | |
1458 | ||
1459 | /* If mount failed, we can still be called without any fc */ | |
d534d31d | 1460 | if (sb->s_root) { |
fcee216b MR |
1461 | last = fuse_mount_remove(fm); |
1462 | if (last) | |
1463 | virtio_fs_conn_destroy(fm); | |
1464 | } | |
1465 | kill_anon_super(sb); | |
a27c061a | 1466 | fuse_mount_destroy(fm); |
fcee216b MR |
1467 | } |
1468 | ||
a62a8ef9 SH |
1469 | static int virtio_fs_test_super(struct super_block *sb, |
1470 | struct fs_context *fsc) | |
1471 | { | |
fcee216b MR |
1472 | struct fuse_mount *fsc_fm = fsc->s_fs_info; |
1473 | struct fuse_mount *sb_fm = get_fuse_mount_super(sb); | |
a62a8ef9 | 1474 | |
fcee216b | 1475 | return fsc_fm->fc->iq.priv == sb_fm->fc->iq.priv; |
a62a8ef9 SH |
1476 | } |
1477 | ||
a62a8ef9 SH |
1478 | static int virtio_fs_get_tree(struct fs_context *fsc) |
1479 | { | |
1480 | struct virtio_fs *fs; | |
1481 | struct super_block *sb; | |
a7f0d7aa | 1482 | struct fuse_conn *fc = NULL; |
fcee216b | 1483 | struct fuse_mount *fm; |
a7f0d7aa CK |
1484 | unsigned int virtqueue_size; |
1485 | int err = -EIO; | |
a62a8ef9 SH |
1486 | |
1487 | /* This gets a reference on virtio_fs object. This ptr gets installed | |
1488 | * in fc->iq->priv. Once fuse_conn is going away, it calls ->put() | |
1489 | * to drop the reference to this object. | |
1490 | */ | |
1491 | fs = virtio_fs_find_instance(fsc->source); | |
1492 | if (!fs) { | |
1493 | pr_info("virtio-fs: tag <%s> not found\n", fsc->source); | |
1494 | return -EINVAL; | |
1495 | } | |
1496 | ||
a7f0d7aa CK |
1497 | virtqueue_size = virtqueue_get_vring_size(fs->vqs[VQ_REQUEST].vq); |
1498 | if (WARN_ON(virtqueue_size <= FUSE_HEADER_OVERHEAD)) | |
1499 | goto out_err; | |
1500 | ||
833c5a42 | 1501 | err = -ENOMEM; |
a62a8ef9 | 1502 | fc = kzalloc(sizeof(struct fuse_conn), GFP_KERNEL); |
833c5a42 MS |
1503 | if (!fc) |
1504 | goto out_err; | |
a62a8ef9 | 1505 | |
fcee216b | 1506 | fm = kzalloc(sizeof(struct fuse_mount), GFP_KERNEL); |
833c5a42 MS |
1507 | if (!fm) |
1508 | goto out_err; | |
fcee216b | 1509 | |
0a7419c6 | 1510 | fuse_conn_init(fc, fm, fsc->user_ns, &virtio_fs_fiq_ops, fs); |
a62a8ef9 SH |
1511 | fc->release = fuse_free_conn; |
1512 | fc->delete_stale = true; | |
bf109c64 | 1513 | fc->auto_submounts = true; |
2d82ab25 | 1514 | fc->sync_fs = true; |
a62a8ef9 | 1515 | |
a7f0d7aa CK |
1516 | /* Tell FUSE to split requests that exceed the virtqueue's size */ |
1517 | fc->max_pages_limit = min_t(unsigned int, fc->max_pages_limit, | |
1518 | virtqueue_size - FUSE_HEADER_OVERHEAD); | |
1519 | ||
fcee216b | 1520 | fsc->s_fs_info = fm; |
b19d3d00 | 1521 | sb = sget_fc(fsc, virtio_fs_test_super, set_anon_super_fc); |
c191cd07 MS |
1522 | if (fsc->s_fs_info) |
1523 | fuse_mount_destroy(fm); | |
a62a8ef9 SH |
1524 | if (IS_ERR(sb)) |
1525 | return PTR_ERR(sb); | |
1526 | ||
1527 | if (!sb->s_root) { | |
1dd53957 | 1528 | err = virtio_fs_fill_super(sb, fsc); |
a62a8ef9 SH |
1529 | if (err) { |
1530 | deactivate_locked_super(sb); | |
1531 | return err; | |
1532 | } | |
1533 | ||
1534 | sb->s_flags |= SB_ACTIVE; | |
1535 | } | |
1536 | ||
1537 | WARN_ON(fsc->root); | |
1538 | fsc->root = dget(sb->s_root); | |
1539 | return 0; | |
833c5a42 MS |
1540 | |
1541 | out_err: | |
1542 | kfree(fc); | |
1543 | mutex_lock(&virtio_fs_mutex); | |
1544 | virtio_fs_put(fs); | |
1545 | mutex_unlock(&virtio_fs_mutex); | |
1546 | return err; | |
a62a8ef9 SH |
1547 | } |
1548 | ||
1549 | static const struct fs_context_operations virtio_fs_context_ops = { | |
84c21507 | 1550 | .free = virtio_fs_free_fsc, |
1dd53957 | 1551 | .parse_param = virtio_fs_parse_param, |
a62a8ef9 SH |
1552 | .get_tree = virtio_fs_get_tree, |
1553 | }; | |
1554 | ||
1555 | static int virtio_fs_init_fs_context(struct fs_context *fsc) | |
1556 | { | |
1dd53957 VG |
1557 | struct fuse_fs_context *ctx; |
1558 | ||
fe0a7bd8 GK |
1559 | if (fsc->purpose == FS_CONTEXT_FOR_SUBMOUNT) |
1560 | return fuse_init_fs_context_submount(fsc); | |
1561 | ||
1dd53957 VG |
1562 | ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL); |
1563 | if (!ctx) | |
1564 | return -ENOMEM; | |
1565 | fsc->fs_private = ctx; | |
a62a8ef9 SH |
1566 | fsc->ops = &virtio_fs_context_ops; |
1567 | return 0; | |
1568 | } | |
1569 | ||
1570 | static struct file_system_type virtio_fs_type = { | |
1571 | .owner = THIS_MODULE, | |
1572 | .name = "virtiofs", | |
1573 | .init_fs_context = virtio_fs_init_fs_context, | |
1574 | .kill_sb = virtio_kill_sb, | |
1575 | }; | |
1576 | ||
9086b2d9 SH |
1577 | static int virtio_fs_uevent(const struct kobject *kobj, struct kobj_uevent_env *env) |
1578 | { | |
1579 | const struct virtio_fs *fs = container_of(kobj, struct virtio_fs, kobj); | |
1580 | ||
1581 | add_uevent_var(env, "TAG=%s", fs->tag); | |
1582 | return 0; | |
1583 | } | |
1584 | ||
1585 | static const struct kset_uevent_ops virtio_fs_uevent_ops = { | |
1586 | .uevent = virtio_fs_uevent, | |
1587 | }; | |
1588 | ||
a8f62f50 SH |
1589 | static int __init virtio_fs_sysfs_init(void) |
1590 | { | |
9086b2d9 SH |
1591 | virtio_fs_kset = kset_create_and_add("virtiofs", &virtio_fs_uevent_ops, |
1592 | fs_kobj); | |
a8f62f50 SH |
1593 | if (!virtio_fs_kset) |
1594 | return -ENOMEM; | |
1595 | return 0; | |
1596 | } | |
1597 | ||
d30ff898 | 1598 | static void virtio_fs_sysfs_exit(void) |
a8f62f50 SH |
1599 | { |
1600 | kset_unregister(virtio_fs_kset); | |
1601 | virtio_fs_kset = NULL; | |
1602 | } | |
1603 | ||
a62a8ef9 SH |
1604 | static int __init virtio_fs_init(void) |
1605 | { | |
1606 | int ret; | |
1607 | ||
a8f62f50 | 1608 | ret = virtio_fs_sysfs_init(); |
a62a8ef9 SH |
1609 | if (ret < 0) |
1610 | return ret; | |
1611 | ||
a8f62f50 SH |
1612 | ret = register_virtio_driver(&virtio_fs_driver); |
1613 | if (ret < 0) | |
1614 | goto sysfs_exit; | |
1615 | ||
a62a8ef9 | 1616 | ret = register_filesystem(&virtio_fs_type); |
a8f62f50 SH |
1617 | if (ret < 0) |
1618 | goto unregister_virtio_driver; | |
a62a8ef9 SH |
1619 | |
1620 | return 0; | |
a8f62f50 SH |
1621 | |
1622 | unregister_virtio_driver: | |
1623 | unregister_virtio_driver(&virtio_fs_driver); | |
1624 | sysfs_exit: | |
1625 | virtio_fs_sysfs_exit(); | |
1626 | return ret; | |
a62a8ef9 SH |
1627 | } |
1628 | module_init(virtio_fs_init); | |
1629 | ||
1630 | static void __exit virtio_fs_exit(void) | |
1631 | { | |
1632 | unregister_filesystem(&virtio_fs_type); | |
1633 | unregister_virtio_driver(&virtio_fs_driver); | |
a8f62f50 | 1634 | virtio_fs_sysfs_exit(); |
a62a8ef9 SH |
1635 | } |
1636 | module_exit(virtio_fs_exit); | |
1637 | ||
1638 | MODULE_AUTHOR("Stefan Hajnoczi <stefanha@redhat.com>"); | |
1639 | MODULE_DESCRIPTION("Virtio Filesystem"); | |
1640 | MODULE_LICENSE("GPL"); | |
1641 | MODULE_ALIAS_FS(KBUILD_MODNAME); | |
1642 | MODULE_DEVICE_TABLE(virtio, id_table); |