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3f054211 | 1 | // SPDX-License-Identifier: GPL-2.0 |
65294c1f | 2 | /* |
3f054211 | 3 | * The NFSD open file cache. |
65294c1f JL |
4 | * |
5 | * (c) 2015 - Jeff Layton <jeff.layton@primarydata.com> | |
b3276c1f CL |
6 | * |
7 | * An nfsd_file object is a per-file collection of open state that binds | |
8 | * together: | |
9 | * - a struct file * | |
10 | * - a user credential | |
11 | * - a network namespace | |
12 | * - a read-ahead context | |
13 | * - monitoring for writeback errors | |
14 | * | |
15 | * nfsd_file objects are reference-counted. Consumers acquire a new | |
16 | * object via the nfsd_file_acquire API. They manage their interest in | |
17 | * the acquired object, and hence the object's reference count, via | |
18 | * nfsd_file_get and nfsd_file_put. There are two varieties of nfsd_file | |
19 | * object: | |
20 | * | |
21 | * * non-garbage-collected: When a consumer wants to precisely control | |
22 | * the lifetime of a file's open state, it acquires a non-garbage- | |
23 | * collected nfsd_file. The final nfsd_file_put releases the open | |
24 | * state immediately. | |
25 | * | |
26 | * * garbage-collected: When a consumer does not control the lifetime | |
27 | * of open state, it acquires a garbage-collected nfsd_file. The | |
28 | * final nfsd_file_put allows the open state to linger for a period | |
29 | * during which it may be re-used. | |
65294c1f JL |
30 | */ |
31 | ||
32 | #include <linux/hash.h> | |
33 | #include <linux/slab.h> | |
65294c1f | 34 | #include <linux/file.h> |
cbcc268b | 35 | #include <linux/pagemap.h> |
65294c1f JL |
36 | #include <linux/sched.h> |
37 | #include <linux/list_lru.h> | |
38 | #include <linux/fsnotify_backend.h> | |
39 | #include <linux/fsnotify.h> | |
40 | #include <linux/seq_file.h> | |
fc22945e | 41 | #include <linux/rhashtable.h> |
65294c1f JL |
42 | |
43 | #include "vfs.h" | |
44 | #include "nfsd.h" | |
45 | #include "nfsfh.h" | |
5e113224 | 46 | #include "netns.h" |
65294c1f JL |
47 | #include "filecache.h" |
48 | #include "trace.h" | |
49 | ||
65294c1f JL |
50 | #define NFSD_LAUNDRETTE_DELAY (2 * HZ) |
51 | ||
c7b824c3 | 52 | #define NFSD_FILE_CACHE_UP (0) |
65294c1f JL |
53 | |
54 | /* We only care about NFSD_MAY_READ/WRITE for this cache */ | |
55 | #define NFSD_FILE_MAY_MASK (NFSD_MAY_READ|NFSD_MAY_WRITE) | |
56 | ||
65294c1f | 57 | static DEFINE_PER_CPU(unsigned long, nfsd_file_cache_hits); |
29d4bdbb | 58 | static DEFINE_PER_CPU(unsigned long, nfsd_file_acquisitions); |
d6329327 | 59 | static DEFINE_PER_CPU(unsigned long, nfsd_file_releases); |
904940e9 | 60 | static DEFINE_PER_CPU(unsigned long, nfsd_file_total_age); |
94660cc1 | 61 | static DEFINE_PER_CPU(unsigned long, nfsd_file_evictions); |
65294c1f | 62 | |
9542e6a6 | 63 | struct nfsd_fcache_disposal { |
9542e6a6 | 64 | struct work_struct work; |
9542e6a6 TM |
65 | spinlock_t lock; |
66 | struct list_head freeme; | |
9542e6a6 TM |
67 | }; |
68 | ||
50d0def9 | 69 | static struct workqueue_struct *nfsd_filecache_wq __read_mostly; |
9542e6a6 | 70 | |
65294c1f JL |
71 | static struct kmem_cache *nfsd_file_slab; |
72 | static struct kmem_cache *nfsd_file_mark_slab; | |
65294c1f | 73 | static struct list_lru nfsd_file_lru; |
c7b824c3 | 74 | static unsigned long nfsd_file_flags; |
65294c1f | 75 | static struct fsnotify_group *nfsd_file_fsnotify_group; |
65294c1f | 76 | static struct delayed_work nfsd_filecache_laundrette; |
c4c649ab | 77 | static struct rhltable nfsd_file_rhltable |
fc22945e CL |
78 | ____cacheline_aligned_in_smp; |
79 | ||
fc22945e CL |
80 | static bool |
81 | nfsd_match_cred(const struct cred *c1, const struct cred *c2) | |
82 | { | |
83 | int i; | |
84 | ||
85 | if (!uid_eq(c1->fsuid, c2->fsuid)) | |
86 | return false; | |
87 | if (!gid_eq(c1->fsgid, c2->fsgid)) | |
88 | return false; | |
89 | if (c1->group_info == NULL || c2->group_info == NULL) | |
90 | return c1->group_info == c2->group_info; | |
91 | if (c1->group_info->ngroups != c2->group_info->ngroups) | |
92 | return false; | |
93 | for (i = 0; i < c1->group_info->ngroups; i++) { | |
94 | if (!gid_eq(c1->group_info->gid[i], c2->group_info->gid[i])) | |
95 | return false; | |
96 | } | |
97 | return true; | |
98 | } | |
99 | ||
fc22945e CL |
100 | static const struct rhashtable_params nfsd_file_rhash_params = { |
101 | .key_len = sizeof_field(struct nfsd_file, nf_inode), | |
102 | .key_offset = offsetof(struct nfsd_file, nf_inode), | |
c4c649ab CL |
103 | .head_offset = offsetof(struct nfsd_file, nf_rlist), |
104 | ||
105 | /* | |
106 | * Start with a single page hash table to reduce resizing churn | |
107 | * on light workloads. | |
108 | */ | |
109 | .min_size = 256, | |
fc22945e CL |
110 | .automatic_shrinking = true, |
111 | }; | |
65294c1f JL |
112 | |
113 | static void | |
9542e6a6 | 114 | nfsd_file_schedule_laundrette(void) |
65294c1f | 115 | { |
22ae4c11 JL |
116 | if (test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags)) |
117 | queue_delayed_work(system_wq, &nfsd_filecache_laundrette, | |
118 | NFSD_LAUNDRETTE_DELAY); | |
65294c1f JL |
119 | } |
120 | ||
121 | static void | |
122 | nfsd_file_slab_free(struct rcu_head *rcu) | |
123 | { | |
124 | struct nfsd_file *nf = container_of(rcu, struct nfsd_file, nf_rcu); | |
125 | ||
126 | put_cred(nf->nf_cred); | |
127 | kmem_cache_free(nfsd_file_slab, nf); | |
128 | } | |
129 | ||
130 | static void | |
131 | nfsd_file_mark_free(struct fsnotify_mark *mark) | |
132 | { | |
133 | struct nfsd_file_mark *nfm = container_of(mark, struct nfsd_file_mark, | |
134 | nfm_mark); | |
135 | ||
136 | kmem_cache_free(nfsd_file_mark_slab, nfm); | |
137 | } | |
138 | ||
139 | static struct nfsd_file_mark * | |
140 | nfsd_file_mark_get(struct nfsd_file_mark *nfm) | |
141 | { | |
689827cd | 142 | if (!refcount_inc_not_zero(&nfm->nfm_ref)) |
65294c1f JL |
143 | return NULL; |
144 | return nfm; | |
145 | } | |
146 | ||
147 | static void | |
148 | nfsd_file_mark_put(struct nfsd_file_mark *nfm) | |
149 | { | |
689827cd | 150 | if (refcount_dec_and_test(&nfm->nfm_ref)) { |
65294c1f JL |
151 | fsnotify_destroy_mark(&nfm->nfm_mark, nfsd_file_fsnotify_group); |
152 | fsnotify_put_mark(&nfm->nfm_mark); | |
153 | } | |
154 | } | |
155 | ||
156 | static struct nfsd_file_mark * | |
427f5f83 | 157 | nfsd_file_mark_find_or_create(struct nfsd_file *nf, struct inode *inode) |
65294c1f JL |
158 | { |
159 | int err; | |
160 | struct fsnotify_mark *mark; | |
161 | struct nfsd_file_mark *nfm = NULL, *new; | |
65294c1f JL |
162 | |
163 | do { | |
b8962a9d | 164 | fsnotify_group_lock(nfsd_file_fsnotify_group); |
65294c1f | 165 | mark = fsnotify_find_mark(&inode->i_fsnotify_marks, |
b8962a9d | 166 | nfsd_file_fsnotify_group); |
65294c1f JL |
167 | if (mark) { |
168 | nfm = nfsd_file_mark_get(container_of(mark, | |
169 | struct nfsd_file_mark, | |
170 | nfm_mark)); | |
b8962a9d | 171 | fsnotify_group_unlock(nfsd_file_fsnotify_group); |
90d2f1da TM |
172 | if (nfm) { |
173 | fsnotify_put_mark(mark); | |
65294c1f | 174 | break; |
90d2f1da TM |
175 | } |
176 | /* Avoid soft lockup race with nfsd_file_mark_put() */ | |
177 | fsnotify_destroy_mark(mark, nfsd_file_fsnotify_group); | |
178 | fsnotify_put_mark(mark); | |
b8962a9d AG |
179 | } else { |
180 | fsnotify_group_unlock(nfsd_file_fsnotify_group); | |
181 | } | |
65294c1f JL |
182 | |
183 | /* allocate a new nfm */ | |
184 | new = kmem_cache_alloc(nfsd_file_mark_slab, GFP_KERNEL); | |
185 | if (!new) | |
186 | return NULL; | |
187 | fsnotify_init_mark(&new->nfm_mark, nfsd_file_fsnotify_group); | |
188 | new->nfm_mark.mask = FS_ATTRIB|FS_DELETE_SELF; | |
689827cd | 189 | refcount_set(&new->nfm_ref, 1); |
65294c1f JL |
190 | |
191 | err = fsnotify_add_inode_mark(&new->nfm_mark, inode, 0); | |
192 | ||
193 | /* | |
194 | * If the add was successful, then return the object. | |
195 | * Otherwise, we need to put the reference we hold on the | |
196 | * nfm_mark. The fsnotify code will take a reference and put | |
197 | * it on failure, so we can't just free it directly. It's also | |
198 | * not safe to call fsnotify_destroy_mark on it as the | |
199 | * mark->group will be NULL. Thus, we can't let the nfm_ref | |
200 | * counter drive the destruction at this point. | |
201 | */ | |
202 | if (likely(!err)) | |
203 | nfm = new; | |
204 | else | |
205 | fsnotify_put_mark(&new->nfm_mark); | |
206 | } while (unlikely(err == -EEXIST)); | |
207 | ||
208 | return nfm; | |
209 | } | |
210 | ||
211 | static struct nfsd_file * | |
c4c649ab CL |
212 | nfsd_file_alloc(struct net *net, struct inode *inode, unsigned char need, |
213 | bool want_gc) | |
65294c1f JL |
214 | { |
215 | struct nfsd_file *nf; | |
216 | ||
217 | nf = kmem_cache_alloc(nfsd_file_slab, GFP_KERNEL); | |
c4c649ab CL |
218 | if (unlikely(!nf)) |
219 | return NULL; | |
220 | ||
221 | INIT_LIST_HEAD(&nf->nf_lru); | |
222 | nf->nf_birthtime = ktime_get(); | |
223 | nf->nf_file = NULL; | |
224 | nf->nf_cred = get_current_cred(); | |
225 | nf->nf_net = net; | |
226 | nf->nf_flags = want_gc ? | |
227 | BIT(NFSD_FILE_HASHED) | BIT(NFSD_FILE_PENDING) | BIT(NFSD_FILE_GC) : | |
228 | BIT(NFSD_FILE_HASHED) | BIT(NFSD_FILE_PENDING); | |
229 | nf->nf_inode = inode; | |
230 | refcount_set(&nf->nf_ref, 1); | |
231 | nf->nf_may = need; | |
232 | nf->nf_mark = NULL; | |
65294c1f JL |
233 | return nf; |
234 | } | |
235 | ||
4c475eee JL |
236 | /** |
237 | * nfsd_file_check_write_error - check for writeback errors on a file | |
238 | * @nf: nfsd_file to check for writeback errors | |
239 | * | |
240 | * Check whether a nfsd_file has an unseen error. Reset the write | |
241 | * verifier if so. | |
242 | */ | |
82141185 | 243 | static void |
82141185 JL |
244 | nfsd_file_check_write_error(struct nfsd_file *nf) |
245 | { | |
246 | struct file *file = nf->nf_file; | |
247 | ||
4c475eee JL |
248 | if ((file->f_mode & FMODE_WRITE) && |
249 | filemap_check_wb_err(file->f_mapping, READ_ONCE(file->f_wb_err))) | |
250 | nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id)); | |
82141185 JL |
251 | } |
252 | ||
253 | static void | |
254 | nfsd_file_hash_remove(struct nfsd_file *nf) | |
255 | { | |
256 | trace_nfsd_file_unhash(nf); | |
c4c649ab CL |
257 | rhltable_remove(&nfsd_file_rhltable, &nf->nf_rlist, |
258 | nfsd_file_rhash_params); | |
82141185 JL |
259 | } |
260 | ||
261 | static bool | |
262 | nfsd_file_unhash(struct nfsd_file *nf) | |
263 | { | |
264 | if (test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) { | |
265 | nfsd_file_hash_remove(nf); | |
266 | return true; | |
267 | } | |
268 | return false; | |
269 | } | |
270 | ||
ac3a2585 | 271 | static void |
65294c1f JL |
272 | nfsd_file_free(struct nfsd_file *nf) |
273 | { | |
904940e9 | 274 | s64 age = ktime_to_ms(ktime_sub(ktime_get(), nf->nf_birthtime)); |
65294c1f | 275 | |
82141185 JL |
276 | trace_nfsd_file_free(nf); |
277 | ||
d6329327 | 278 | this_cpu_inc(nfsd_file_releases); |
904940e9 | 279 | this_cpu_add(nfsd_file_total_age, age); |
d6329327 | 280 | |
ac3a2585 | 281 | nfsd_file_unhash(nf); |
65294c1f JL |
282 | if (nf->nf_mark) |
283 | nfsd_file_mark_put(nf->nf_mark); | |
284 | if (nf->nf_file) { | |
4c475eee | 285 | nfsd_file_check_write_error(nf); |
b2ff1bd7 | 286 | filp_close(nf->nf_file, NULL); |
65294c1f | 287 | } |
668ed92e CL |
288 | |
289 | /* | |
290 | * If this item is still linked via nf_lru, that's a bug. | |
291 | * WARN and leak it to preserve system stability. | |
292 | */ | |
293 | if (WARN_ON_ONCE(!list_empty(&nf->nf_lru))) | |
ac3a2585 | 294 | return; |
668ed92e | 295 | |
65294c1f | 296 | call_rcu(&nf->nf_rcu, nfsd_file_slab_free); |
65294c1f JL |
297 | } |
298 | ||
055b24a8 TM |
299 | static bool |
300 | nfsd_file_check_writeback(struct nfsd_file *nf) | |
301 | { | |
302 | struct file *file = nf->nf_file; | |
303 | struct address_space *mapping; | |
304 | ||
dcb779fc JL |
305 | /* File not open for write? */ |
306 | if (!(file->f_mode & FMODE_WRITE)) | |
055b24a8 | 307 | return false; |
dcb779fc JL |
308 | |
309 | /* | |
310 | * Some filesystems (e.g. NFS) flush all dirty data on close. | |
311 | * On others, there is no need to wait for writeback. | |
312 | */ | |
313 | if (!(file_inode(file)->i_sb->s_export_op->flags & EXPORT_OP_FLUSH_ON_CLOSE)) | |
314 | return false; | |
315 | ||
055b24a8 TM |
316 | mapping = file->f_mapping; |
317 | return mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) || | |
318 | mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK); | |
319 | } | |
320 | ||
dcb779fc | 321 | |
ac3a2585 | 322 | static bool nfsd_file_lru_add(struct nfsd_file *nf) |
65294c1f | 323 | { |
4a0e73e6 | 324 | set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags); |
ac3a2585 | 325 | if (list_lru_add(&nfsd_file_lru, &nf->nf_lru)) { |
c46203ac | 326 | trace_nfsd_file_lru_add(nf); |
ac3a2585 JL |
327 | return true; |
328 | } | |
329 | return false; | |
c46203ac | 330 | } |
65294c1f | 331 | |
ac3a2585 | 332 | static bool nfsd_file_lru_remove(struct nfsd_file *nf) |
c46203ac | 333 | { |
ac3a2585 | 334 | if (list_lru_del(&nfsd_file_lru, &nf->nf_lru)) { |
c46203ac | 335 | trace_nfsd_file_lru_del(nf); |
ac3a2585 JL |
336 | return true; |
337 | } | |
338 | return false; | |
c46203ac CL |
339 | } |
340 | ||
82141185 JL |
341 | struct nfsd_file * |
342 | nfsd_file_get(struct nfsd_file *nf) | |
65294c1f | 343 | { |
70f62231 | 344 | if (nf && refcount_inc_not_zero(&nf->nf_ref)) |
82141185 JL |
345 | return nf; |
346 | return NULL; | |
65294c1f JL |
347 | } |
348 | ||
ac3a2585 JL |
349 | /** |
350 | * nfsd_file_put - put the reference to a nfsd_file | |
351 | * @nf: nfsd_file of which to put the reference | |
352 | * | |
353 | * Put a reference to a nfsd_file. In the non-GC case, we just put the | |
354 | * reference immediately. In the GC case, if the reference would be | |
355 | * the last one, the put it on the LRU instead to be cleaned up later. | |
356 | */ | |
65294c1f JL |
357 | void |
358 | nfsd_file_put(struct nfsd_file *nf) | |
359 | { | |
08af54b3 | 360 | might_sleep(); |
ac3a2585 | 361 | trace_nfsd_file_put(nf); |
08af54b3 | 362 | |
ac3a2585 JL |
363 | if (test_bit(NFSD_FILE_GC, &nf->nf_flags) && |
364 | test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) { | |
365 | /* | |
366 | * If this is the last reference (nf_ref == 1), then try to | |
367 | * transfer it to the LRU. | |
368 | */ | |
369 | if (refcount_dec_not_one(&nf->nf_ref)) | |
370 | return; | |
371 | ||
372 | /* Try to add it to the LRU. If that fails, decrement. */ | |
373 | if (nfsd_file_lru_add(nf)) { | |
374 | /* If it's still hashed, we're done */ | |
375 | if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) { | |
376 | nfsd_file_schedule_laundrette(); | |
377 | return; | |
378 | } | |
65294c1f | 379 | |
ac3a2585 JL |
380 | /* |
381 | * We're racing with unhashing, so try to remove it from | |
382 | * the LRU. If removal fails, then someone else already | |
383 | * has our reference. | |
384 | */ | |
385 | if (!nfsd_file_lru_remove(nf)) | |
386 | return; | |
387 | } | |
65294c1f | 388 | } |
ac3a2585 JL |
389 | if (refcount_dec_and_test(&nf->nf_ref)) |
390 | nfsd_file_free(nf); | |
65294c1f JL |
391 | } |
392 | ||
393 | static void | |
ac3a2585 | 394 | nfsd_file_dispose_list(struct list_head *dispose) |
65294c1f | 395 | { |
65294c1f JL |
396 | struct nfsd_file *nf; |
397 | ||
ac3a2585 | 398 | while (!list_empty(dispose)) { |
65294c1f | 399 | nf = list_first_entry(dispose, struct nfsd_file, nf_lru); |
668ed92e | 400 | list_del_init(&nf->nf_lru); |
ac3a2585 | 401 | nfsd_file_free(nf); |
65294c1f | 402 | } |
65294c1f JL |
403 | } |
404 | ||
92e4a673 JL |
405 | /** |
406 | * nfsd_file_dispose_list_delayed - move list of dead files to net's freeme list | |
407 | * @dispose: list of nfsd_files to be disposed | |
408 | * | |
409 | * Transfers each file to the "freeme" list for its nfsd_net, to eventually | |
410 | * be disposed of by the per-net garbage collector. | |
411 | */ | |
9542e6a6 TM |
412 | static void |
413 | nfsd_file_dispose_list_delayed(struct list_head *dispose) | |
414 | { | |
9542e6a6 | 415 | while(!list_empty(dispose)) { |
92e4a673 JL |
416 | struct nfsd_file *nf = list_first_entry(dispose, |
417 | struct nfsd_file, nf_lru); | |
418 | struct nfsd_net *nn = net_generic(nf->nf_net, nfsd_net_id); | |
419 | struct nfsd_fcache_disposal *l = nn->fcache_disposal; | |
420 | ||
421 | spin_lock(&l->lock); | |
422 | list_move_tail(&nf->nf_lru, &l->freeme); | |
423 | spin_unlock(&l->lock); | |
424 | queue_work(nfsd_filecache_wq, &l->work); | |
9542e6a6 TM |
425 | } |
426 | } | |
427 | ||
4a0e73e6 CL |
428 | /** |
429 | * nfsd_file_lru_cb - Examine an entry on the LRU list | |
430 | * @item: LRU entry to examine | |
431 | * @lru: controlling LRU | |
432 | * @lock: LRU list lock (unused) | |
433 | * @arg: dispose list | |
434 | * | |
4a0e73e6 CL |
435 | * Return values: |
436 | * %LRU_REMOVED: @item was removed from the LRU | |
edead3a5 | 437 | * %LRU_ROTATE: @item is to be moved to the LRU tail |
4a0e73e6 | 438 | * %LRU_SKIP: @item cannot be evicted |
65294c1f JL |
439 | */ |
440 | static enum lru_status | |
441 | nfsd_file_lru_cb(struct list_head *item, struct list_lru_one *lru, | |
442 | spinlock_t *lock, void *arg) | |
443 | __releases(lock) | |
444 | __acquires(lock) | |
445 | { | |
446 | struct list_head *head = arg; | |
447 | struct nfsd_file *nf = list_entry(item, struct nfsd_file, nf_lru); | |
448 | ||
ac3a2585 JL |
449 | /* We should only be dealing with GC entries here */ |
450 | WARN_ON_ONCE(!test_bit(NFSD_FILE_GC, &nf->nf_flags)); | |
055b24a8 TM |
451 | |
452 | /* | |
453 | * Don't throw out files that are still undergoing I/O or | |
454 | * that have uncleared errors pending. | |
455 | */ | |
c46203ac CL |
456 | if (nfsd_file_check_writeback(nf)) { |
457 | trace_nfsd_file_gc_writeback(nf); | |
458 | return LRU_SKIP; | |
459 | } | |
055b24a8 | 460 | |
ac3a2585 | 461 | /* If it was recently added to the list, skip it */ |
c46203ac CL |
462 | if (test_and_clear_bit(NFSD_FILE_REFERENCED, &nf->nf_flags)) { |
463 | trace_nfsd_file_gc_referenced(nf); | |
edead3a5 | 464 | return LRU_ROTATE; |
c46203ac | 465 | } |
65294c1f | 466 | |
ac3a2585 JL |
467 | /* |
468 | * Put the reference held on behalf of the LRU. If it wasn't the last | |
469 | * one, then just remove it from the LRU and ignore it. | |
470 | */ | |
471 | if (!refcount_dec_and_test(&nf->nf_ref)) { | |
472 | trace_nfsd_file_gc_in_use(nf); | |
473 | list_lru_isolate(lru, &nf->nf_lru); | |
474 | return LRU_REMOVED; | |
c46203ac | 475 | } |
65294c1f | 476 | |
ac3a2585 JL |
477 | /* Refcount went to zero. Unhash it and queue it to the dispose list */ |
478 | nfsd_file_unhash(nf); | |
65294c1f | 479 | list_lru_isolate_move(lru, &nf->nf_lru, head); |
94660cc1 | 480 | this_cpu_inc(nfsd_file_evictions); |
c46203ac | 481 | trace_nfsd_file_gc_disposed(nf); |
65294c1f | 482 | return LRU_REMOVED; |
65294c1f JL |
483 | } |
484 | ||
9542e6a6 TM |
485 | static void |
486 | nfsd_file_gc(void) | |
487 | { | |
3bc6d347 | 488 | LIST_HEAD(dispose); |
94660cc1 | 489 | unsigned long ret; |
3bc6d347 | 490 | |
94660cc1 | 491 | ret = list_lru_walk(&nfsd_file_lru, nfsd_file_lru_cb, |
edead3a5 | 492 | &dispose, list_lru_count(&nfsd_file_lru)); |
94660cc1 | 493 | trace_nfsd_file_gc_removed(ret, list_lru_count(&nfsd_file_lru)); |
ac3a2585 | 494 | nfsd_file_dispose_list_delayed(&dispose); |
9542e6a6 TM |
495 | } |
496 | ||
497 | static void | |
498 | nfsd_file_gc_worker(struct work_struct *work) | |
499 | { | |
500 | nfsd_file_gc(); | |
22ae4c11 JL |
501 | if (list_lru_count(&nfsd_file_lru)) |
502 | nfsd_file_schedule_laundrette(); | |
65294c1f JL |
503 | } |
504 | ||
505 | static unsigned long | |
506 | nfsd_file_lru_count(struct shrinker *s, struct shrink_control *sc) | |
507 | { | |
508 | return list_lru_count(&nfsd_file_lru); | |
509 | } | |
510 | ||
511 | static unsigned long | |
512 | nfsd_file_lru_scan(struct shrinker *s, struct shrink_control *sc) | |
513 | { | |
39f1d1ff CL |
514 | LIST_HEAD(dispose); |
515 | unsigned long ret; | |
516 | ||
517 | ret = list_lru_shrink_walk(&nfsd_file_lru, sc, | |
518 | nfsd_file_lru_cb, &dispose); | |
94660cc1 | 519 | trace_nfsd_file_shrinker_removed(ret, list_lru_count(&nfsd_file_lru)); |
ac3a2585 | 520 | nfsd_file_dispose_list_delayed(&dispose); |
39f1d1ff | 521 | return ret; |
65294c1f JL |
522 | } |
523 | ||
524 | static struct shrinker nfsd_file_shrinker = { | |
525 | .scan_objects = nfsd_file_lru_scan, | |
526 | .count_objects = nfsd_file_lru_count, | |
527 | .seeks = 1, | |
528 | }; | |
529 | ||
4bdbba54 JL |
530 | /** |
531 | * nfsd_file_cond_queue - conditionally unhash and queue a nfsd_file | |
532 | * @nf: nfsd_file to attempt to queue | |
533 | * @dispose: private list to queue successfully-put objects | |
534 | * | |
535 | * Unhash an nfsd_file, try to get a reference to it, and then put that | |
536 | * reference. If it's the last reference, queue it to the dispose list. | |
537 | */ | |
538 | static void | |
539 | nfsd_file_cond_queue(struct nfsd_file *nf, struct list_head *dispose) | |
540 | __must_hold(RCU) | |
541 | { | |
542 | int decrement = 1; | |
543 | ||
544 | /* If we raced with someone else unhashing, ignore it */ | |
545 | if (!nfsd_file_unhash(nf)) | |
546 | return; | |
547 | ||
548 | /* If we can't get a reference, ignore it */ | |
549 | if (!nfsd_file_get(nf)) | |
550 | return; | |
551 | ||
552 | /* Extra decrement if we remove from the LRU */ | |
553 | if (nfsd_file_lru_remove(nf)) | |
554 | ++decrement; | |
555 | ||
556 | /* If refcount goes to 0, then put on the dispose list */ | |
557 | if (refcount_sub_and_test(decrement, &nf->nf_ref)) { | |
558 | list_add(&nf->nf_lru, dispose); | |
559 | trace_nfsd_file_closing(nf); | |
560 | } | |
561 | } | |
562 | ||
ac3a2585 JL |
563 | /** |
564 | * nfsd_file_queue_for_close: try to close out any open nfsd_files for an inode | |
565 | * @inode: inode on which to close out nfsd_files | |
566 | * @dispose: list on which to gather nfsd_files to close out | |
567 | * | |
c4c649ab CL |
568 | * An nfsd_file represents a struct file being held open on behalf of nfsd. |
569 | * An open file however can block other activity (such as leases), or cause | |
ac3a2585 JL |
570 | * undesirable behavior (e.g. spurious silly-renames when reexporting NFS). |
571 | * | |
572 | * This function is intended to find open nfsd_files when this sort of | |
573 | * conflicting access occurs and then attempt to close those files out. | |
574 | * | |
575 | * Populates the dispose list with entries that have already had their | |
576 | * refcounts go to zero. The actual free of an nfsd_file can be expensive, | |
577 | * so we leave it up to the caller whether it wants to wait or not. | |
a8455110 | 578 | */ |
ac3a2585 JL |
579 | static void |
580 | nfsd_file_queue_for_close(struct inode *inode, struct list_head *dispose) | |
65294c1f | 581 | { |
c4c649ab | 582 | struct rhlist_head *tmp, *list; |
ce502f81 | 583 | struct nfsd_file *nf; |
65294c1f | 584 | |
ce502f81 | 585 | rcu_read_lock(); |
c4c649ab CL |
586 | list = rhltable_lookup(&nfsd_file_rhltable, &inode, |
587 | nfsd_file_rhash_params); | |
588 | rhl_for_each_entry_rcu(nf, tmp, list, nf_rlist) { | |
589 | if (!test_bit(NFSD_FILE_GC, &nf->nf_flags)) | |
590 | continue; | |
4bdbba54 | 591 | nfsd_file_cond_queue(nf, dispose); |
c4c649ab | 592 | } |
ce502f81 | 593 | rcu_read_unlock(); |
65294c1f JL |
594 | } |
595 | ||
596 | /** | |
ac3a2585 | 597 | * nfsd_file_close_inode - attempt a delayed close of a nfsd_file |
65294c1f JL |
598 | * @inode: inode of the file to attempt to remove |
599 | * | |
ac3a2585 JL |
600 | * Close out any open nfsd_files that can be reaped for @inode. The |
601 | * actual freeing is deferred to the dispose_list_delayed infrastructure. | |
602 | * | |
603 | * This is used by the fsnotify callbacks and setlease notifier. | |
65294c1f | 604 | */ |
ac3a2585 JL |
605 | static void |
606 | nfsd_file_close_inode(struct inode *inode) | |
65294c1f | 607 | { |
65294c1f JL |
608 | LIST_HEAD(dispose); |
609 | ||
ac3a2585 JL |
610 | nfsd_file_queue_for_close(inode, &dispose); |
611 | nfsd_file_dispose_list_delayed(&dispose); | |
65294c1f JL |
612 | } |
613 | ||
614 | /** | |
ac3a2585 | 615 | * nfsd_file_close_inode_sync - attempt to forcibly close a nfsd_file |
65294c1f JL |
616 | * @inode: inode of the file to attempt to remove |
617 | * | |
ac3a2585 JL |
618 | * Close out any open nfsd_files that can be reaped for @inode. The |
619 | * nfsd_files are closed out synchronously. | |
620 | * | |
621 | * This is called from nfsd_rename and nfsd_unlink to avoid silly-renames | |
622 | * when reexporting NFS. | |
65294c1f | 623 | */ |
ac3a2585 JL |
624 | void |
625 | nfsd_file_close_inode_sync(struct inode *inode) | |
65294c1f | 626 | { |
ac3a2585 | 627 | struct nfsd_file *nf; |
65294c1f JL |
628 | LIST_HEAD(dispose); |
629 | ||
ac3a2585 JL |
630 | trace_nfsd_file_close(inode); |
631 | ||
632 | nfsd_file_queue_for_close(inode, &dispose); | |
633 | while (!list_empty(&dispose)) { | |
634 | nf = list_first_entry(&dispose, struct nfsd_file, nf_lru); | |
635 | list_del_init(&nf->nf_lru); | |
636 | nfsd_file_free(nf); | |
637 | } | |
638 | flush_delayed_fput(); | |
65294c1f JL |
639 | } |
640 | ||
641 | /** | |
642 | * nfsd_file_delayed_close - close unused nfsd_files | |
643 | * @work: dummy | |
644 | * | |
92e4a673 JL |
645 | * Scrape the freeme list for this nfsd_net, and then dispose of them |
646 | * all. | |
65294c1f JL |
647 | */ |
648 | static void | |
649 | nfsd_file_delayed_close(struct work_struct *work) | |
650 | { | |
651 | LIST_HEAD(head); | |
9542e6a6 TM |
652 | struct nfsd_fcache_disposal *l = container_of(work, |
653 | struct nfsd_fcache_disposal, work); | |
65294c1f | 654 | |
92e4a673 JL |
655 | spin_lock(&l->lock); |
656 | list_splice_init(&l->freeme, &head); | |
657 | spin_unlock(&l->lock); | |
658 | ||
9542e6a6 | 659 | nfsd_file_dispose_list(&head); |
65294c1f JL |
660 | } |
661 | ||
662 | static int | |
663 | nfsd_file_lease_notifier_call(struct notifier_block *nb, unsigned long arg, | |
664 | void *data) | |
665 | { | |
666 | struct file_lock *fl = data; | |
667 | ||
668 | /* Only close files for F_SETLEASE leases */ | |
669 | if (fl->fl_flags & FL_LEASE) | |
ac3a2585 | 670 | nfsd_file_close_inode(file_inode(fl->fl_file)); |
65294c1f JL |
671 | return 0; |
672 | } | |
673 | ||
674 | static struct notifier_block nfsd_file_lease_notifier = { | |
675 | .notifier_call = nfsd_file_lease_notifier_call, | |
676 | }; | |
677 | ||
678 | static int | |
b9a1b977 AG |
679 | nfsd_file_fsnotify_handle_event(struct fsnotify_mark *mark, u32 mask, |
680 | struct inode *inode, struct inode *dir, | |
950cc0d2 | 681 | const struct qstr *name, u32 cookie) |
65294c1f | 682 | { |
24dca905 GKB |
683 | if (WARN_ON_ONCE(!inode)) |
684 | return 0; | |
685 | ||
65294c1f JL |
686 | trace_nfsd_file_fsnotify_handle_event(inode, mask); |
687 | ||
688 | /* Should be no marks on non-regular files */ | |
689 | if (!S_ISREG(inode->i_mode)) { | |
690 | WARN_ON_ONCE(1); | |
691 | return 0; | |
692 | } | |
693 | ||
694 | /* don't close files if this was not the last link */ | |
695 | if (mask & FS_ATTRIB) { | |
696 | if (inode->i_nlink) | |
697 | return 0; | |
698 | } | |
699 | ||
700 | nfsd_file_close_inode(inode); | |
701 | return 0; | |
702 | } | |
703 | ||
704 | ||
705 | static const struct fsnotify_ops nfsd_file_fsnotify_ops = { | |
b9a1b977 | 706 | .handle_inode_event = nfsd_file_fsnotify_handle_event, |
65294c1f JL |
707 | .free_mark = nfsd_file_mark_free, |
708 | }; | |
709 | ||
710 | int | |
711 | nfsd_file_cache_init(void) | |
712 | { | |
0ec8e9d1 | 713 | int ret; |
65294c1f | 714 | |
c7b824c3 CL |
715 | lockdep_assert_held(&nfsd_mutex); |
716 | if (test_and_set_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 1) | |
65294c1f JL |
717 | return 0; |
718 | ||
c4c649ab | 719 | ret = rhltable_init(&nfsd_file_rhltable, &nfsd_file_rhash_params); |
fc22945e CL |
720 | if (ret) |
721 | return ret; | |
722 | ||
723 | ret = -ENOMEM; | |
9542e6a6 TM |
724 | nfsd_filecache_wq = alloc_workqueue("nfsd_filecache", 0, 0); |
725 | if (!nfsd_filecache_wq) | |
726 | goto out; | |
727 | ||
65294c1f JL |
728 | nfsd_file_slab = kmem_cache_create("nfsd_file", |
729 | sizeof(struct nfsd_file), 0, 0, NULL); | |
730 | if (!nfsd_file_slab) { | |
731 | pr_err("nfsd: unable to create nfsd_file_slab\n"); | |
732 | goto out_err; | |
733 | } | |
734 | ||
735 | nfsd_file_mark_slab = kmem_cache_create("nfsd_file_mark", | |
736 | sizeof(struct nfsd_file_mark), 0, 0, NULL); | |
737 | if (!nfsd_file_mark_slab) { | |
738 | pr_err("nfsd: unable to create nfsd_file_mark_slab\n"); | |
739 | goto out_err; | |
740 | } | |
741 | ||
742 | ||
743 | ret = list_lru_init(&nfsd_file_lru); | |
744 | if (ret) { | |
745 | pr_err("nfsd: failed to init nfsd_file_lru: %d\n", ret); | |
746 | goto out_err; | |
747 | } | |
748 | ||
e33c267a | 749 | ret = register_shrinker(&nfsd_file_shrinker, "nfsd-filecache"); |
65294c1f JL |
750 | if (ret) { |
751 | pr_err("nfsd: failed to register nfsd_file_shrinker: %d\n", ret); | |
752 | goto out_lru; | |
753 | } | |
754 | ||
755 | ret = lease_register_notifier(&nfsd_file_lease_notifier); | |
756 | if (ret) { | |
757 | pr_err("nfsd: unable to register lease notifier: %d\n", ret); | |
758 | goto out_shrinker; | |
759 | } | |
760 | ||
867a448d | 761 | nfsd_file_fsnotify_group = fsnotify_alloc_group(&nfsd_file_fsnotify_ops, |
b8962a9d | 762 | FSNOTIFY_GROUP_NOFS); |
65294c1f JL |
763 | if (IS_ERR(nfsd_file_fsnotify_group)) { |
764 | pr_err("nfsd: unable to create fsnotify group: %ld\n", | |
765 | PTR_ERR(nfsd_file_fsnotify_group)); | |
231307df | 766 | ret = PTR_ERR(nfsd_file_fsnotify_group); |
65294c1f JL |
767 | nfsd_file_fsnotify_group = NULL; |
768 | goto out_notifier; | |
769 | } | |
770 | ||
9542e6a6 | 771 | INIT_DELAYED_WORK(&nfsd_filecache_laundrette, nfsd_file_gc_worker); |
65294c1f JL |
772 | out: |
773 | return ret; | |
774 | out_notifier: | |
775 | lease_unregister_notifier(&nfsd_file_lease_notifier); | |
776 | out_shrinker: | |
777 | unregister_shrinker(&nfsd_file_shrinker); | |
778 | out_lru: | |
779 | list_lru_destroy(&nfsd_file_lru); | |
780 | out_err: | |
781 | kmem_cache_destroy(nfsd_file_slab); | |
782 | nfsd_file_slab = NULL; | |
783 | kmem_cache_destroy(nfsd_file_mark_slab); | |
784 | nfsd_file_mark_slab = NULL; | |
9542e6a6 TM |
785 | destroy_workqueue(nfsd_filecache_wq); |
786 | nfsd_filecache_wq = NULL; | |
c4c649ab | 787 | rhltable_destroy(&nfsd_file_rhltable); |
65294c1f JL |
788 | goto out; |
789 | } | |
790 | ||
ac3a2585 JL |
791 | /** |
792 | * __nfsd_file_cache_purge: clean out the cache for shutdown | |
793 | * @net: net-namespace to shut down the cache (may be NULL) | |
794 | * | |
795 | * Walk the nfsd_file cache and close out any that match @net. If @net is NULL, | |
972cc0e0 JL |
796 | * then close out everything. Called when an nfsd instance is being shut down, |
797 | * and when the exports table is flushed. | |
ac3a2585 | 798 | */ |
c7b824c3 CL |
799 | static void |
800 | __nfsd_file_cache_purge(struct net *net) | |
65294c1f | 801 | { |
ce502f81 CL |
802 | struct rhashtable_iter iter; |
803 | struct nfsd_file *nf; | |
65294c1f | 804 | LIST_HEAD(dispose); |
65294c1f | 805 | |
c4c649ab | 806 | rhltable_walk_enter(&nfsd_file_rhltable, &iter); |
ce502f81 CL |
807 | do { |
808 | rhashtable_walk_start(&iter); | |
5e113224 | 809 | |
ce502f81 CL |
810 | nf = rhashtable_walk_next(&iter); |
811 | while (!IS_ERR_OR_NULL(nf)) { | |
4bdbba54 JL |
812 | if (!net || nf->nf_net == net) |
813 | nfsd_file_cond_queue(nf, &dispose); | |
ce502f81 | 814 | nf = rhashtable_walk_next(&iter); |
65294c1f | 815 | } |
ce502f81 CL |
816 | |
817 | rhashtable_walk_stop(&iter); | |
818 | } while (nf == ERR_PTR(-EAGAIN)); | |
819 | rhashtable_walk_exit(&iter); | |
820 | ||
821 | nfsd_file_dispose_list(&dispose); | |
65294c1f JL |
822 | } |
823 | ||
9542e6a6 | 824 | static struct nfsd_fcache_disposal * |
1463b38e | 825 | nfsd_alloc_fcache_disposal(void) |
9542e6a6 TM |
826 | { |
827 | struct nfsd_fcache_disposal *l; | |
828 | ||
829 | l = kmalloc(sizeof(*l), GFP_KERNEL); | |
830 | if (!l) | |
831 | return NULL; | |
832 | INIT_WORK(&l->work, nfsd_file_delayed_close); | |
9542e6a6 TM |
833 | spin_lock_init(&l->lock); |
834 | INIT_LIST_HEAD(&l->freeme); | |
835 | return l; | |
836 | } | |
837 | ||
838 | static void | |
839 | nfsd_free_fcache_disposal(struct nfsd_fcache_disposal *l) | |
840 | { | |
9542e6a6 TM |
841 | cancel_work_sync(&l->work); |
842 | nfsd_file_dispose_list(&l->freeme); | |
1463b38e | 843 | kfree(l); |
9542e6a6 TM |
844 | } |
845 | ||
846 | static void | |
847 | nfsd_free_fcache_disposal_net(struct net *net) | |
848 | { | |
1463b38e N |
849 | struct nfsd_net *nn = net_generic(net, nfsd_net_id); |
850 | struct nfsd_fcache_disposal *l = nn->fcache_disposal; | |
9542e6a6 | 851 | |
1463b38e | 852 | nfsd_free_fcache_disposal(l); |
9542e6a6 TM |
853 | } |
854 | ||
855 | int | |
856 | nfsd_file_cache_start_net(struct net *net) | |
857 | { | |
1463b38e N |
858 | struct nfsd_net *nn = net_generic(net, nfsd_net_id); |
859 | ||
860 | nn->fcache_disposal = nfsd_alloc_fcache_disposal(); | |
861 | return nn->fcache_disposal ? 0 : -ENOMEM; | |
9542e6a6 TM |
862 | } |
863 | ||
c7b824c3 CL |
864 | /** |
865 | * nfsd_file_cache_purge - Remove all cache items associated with @net | |
866 | * @net: target net namespace | |
867 | * | |
868 | */ | |
869 | void | |
870 | nfsd_file_cache_purge(struct net *net) | |
871 | { | |
872 | lockdep_assert_held(&nfsd_mutex); | |
873 | if (test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 1) | |
874 | __nfsd_file_cache_purge(net); | |
875 | } | |
876 | ||
9542e6a6 TM |
877 | void |
878 | nfsd_file_cache_shutdown_net(struct net *net) | |
879 | { | |
880 | nfsd_file_cache_purge(net); | |
881 | nfsd_free_fcache_disposal_net(net); | |
882 | } | |
883 | ||
65294c1f JL |
884 | void |
885 | nfsd_file_cache_shutdown(void) | |
886 | { | |
8b330f78 CL |
887 | int i; |
888 | ||
c7b824c3 CL |
889 | lockdep_assert_held(&nfsd_mutex); |
890 | if (test_and_clear_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 0) | |
891 | return; | |
65294c1f JL |
892 | |
893 | lease_unregister_notifier(&nfsd_file_lease_notifier); | |
894 | unregister_shrinker(&nfsd_file_shrinker); | |
895 | /* | |
896 | * make sure all callers of nfsd_file_lru_cb are done before | |
897 | * calling nfsd_file_cache_purge | |
898 | */ | |
899 | cancel_delayed_work_sync(&nfsd_filecache_laundrette); | |
c7b824c3 | 900 | __nfsd_file_cache_purge(NULL); |
65294c1f JL |
901 | list_lru_destroy(&nfsd_file_lru); |
902 | rcu_barrier(); | |
903 | fsnotify_put_group(nfsd_file_fsnotify_group); | |
904 | nfsd_file_fsnotify_group = NULL; | |
905 | kmem_cache_destroy(nfsd_file_slab); | |
906 | nfsd_file_slab = NULL; | |
907 | fsnotify_wait_marks_destroyed(); | |
908 | kmem_cache_destroy(nfsd_file_mark_slab); | |
909 | nfsd_file_mark_slab = NULL; | |
9542e6a6 TM |
910 | destroy_workqueue(nfsd_filecache_wq); |
911 | nfsd_filecache_wq = NULL; | |
c4c649ab | 912 | rhltable_destroy(&nfsd_file_rhltable); |
8b330f78 CL |
913 | |
914 | for_each_possible_cpu(i) { | |
915 | per_cpu(nfsd_file_cache_hits, i) = 0; | |
916 | per_cpu(nfsd_file_acquisitions, i) = 0; | |
917 | per_cpu(nfsd_file_releases, i) = 0; | |
918 | per_cpu(nfsd_file_total_age, i) = 0; | |
8b330f78 | 919 | per_cpu(nfsd_file_evictions, i) = 0; |
65294c1f | 920 | } |
65294c1f JL |
921 | } |
922 | ||
c4c649ab CL |
923 | static struct nfsd_file * |
924 | nfsd_file_lookup_locked(const struct net *net, const struct cred *cred, | |
925 | struct inode *inode, unsigned char need, | |
926 | bool want_gc) | |
927 | { | |
928 | struct rhlist_head *tmp, *list; | |
929 | struct nfsd_file *nf; | |
930 | ||
931 | list = rhltable_lookup(&nfsd_file_rhltable, &inode, | |
932 | nfsd_file_rhash_params); | |
933 | rhl_for_each_entry_rcu(nf, tmp, list, nf_rlist) { | |
934 | if (nf->nf_may != need) | |
935 | continue; | |
936 | if (nf->nf_net != net) | |
937 | continue; | |
938 | if (!nfsd_match_cred(nf->nf_cred, cred)) | |
939 | continue; | |
940 | if (test_bit(NFSD_FILE_GC, &nf->nf_flags) != want_gc) | |
941 | continue; | |
942 | if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags) == 0) | |
943 | continue; | |
944 | ||
945 | if (!nfsd_file_get(nf)) | |
946 | continue; | |
947 | return nf; | |
948 | } | |
949 | return NULL; | |
950 | } | |
951 | ||
65294c1f | 952 | /** |
ce502f81 CL |
953 | * nfsd_file_is_cached - are there any cached open files for this inode? |
954 | * @inode: inode to check | |
955 | * | |
956 | * The lookup matches inodes in all net namespaces and is atomic wrt | |
957 | * nfsd_file_acquire(). | |
65294c1f | 958 | * |
ce502f81 CL |
959 | * Return values: |
960 | * %true: filecache contains at least one file matching this inode | |
961 | * %false: filecache contains no files matching this inode | |
65294c1f JL |
962 | */ |
963 | bool | |
964 | nfsd_file_is_cached(struct inode *inode) | |
965 | { | |
c4c649ab CL |
966 | struct rhlist_head *tmp, *list; |
967 | struct nfsd_file *nf; | |
ce502f81 CL |
968 | bool ret = false; |
969 | ||
c4c649ab CL |
970 | rcu_read_lock(); |
971 | list = rhltable_lookup(&nfsd_file_rhltable, &inode, | |
972 | nfsd_file_rhash_params); | |
973 | rhl_for_each_entry_rcu(nf, tmp, list, nf_rlist) | |
974 | if (test_bit(NFSD_FILE_GC, &nf->nf_flags)) { | |
975 | ret = true; | |
976 | break; | |
977 | } | |
978 | rcu_read_unlock(); | |
979 | ||
54f7df70 | 980 | trace_nfsd_file_is_cached(inode, (int)ret); |
65294c1f JL |
981 | return ret; |
982 | } | |
983 | ||
fb70bf12 | 984 | static __be32 |
be023006 | 985 | nfsd_file_do_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, |
0b3a551f JL |
986 | unsigned int may_flags, struct file *file, |
987 | struct nfsd_file **pnf, bool want_gc) | |
65294c1f | 988 | { |
c4c649ab CL |
989 | unsigned char need = may_flags & NFSD_FILE_MAY_MASK; |
990 | struct net *net = SVC_NET(rqstp); | |
991 | struct nfsd_file *new, *nf; | |
992 | const struct cred *cred; | |
243a5263 | 993 | bool open_retry = true; |
c4c649ab | 994 | struct inode *inode; |
ce502f81 | 995 | __be32 status; |
243a5263 | 996 | int ret; |
65294c1f | 997 | |
65294c1f JL |
998 | status = fh_verify(rqstp, fhp, S_IFREG, |
999 | may_flags|NFSD_MAY_OWNER_OVERRIDE); | |
1000 | if (status != nfs_ok) | |
1001 | return status; | |
c4c649ab CL |
1002 | inode = d_inode(fhp->fh_dentry); |
1003 | cred = get_current_cred(); | |
65294c1f | 1004 | |
65294c1f | 1005 | retry: |
243a5263 | 1006 | rcu_read_lock(); |
c4c649ab | 1007 | nf = nfsd_file_lookup_locked(net, cred, inode, need, want_gc); |
243a5263 | 1008 | rcu_read_unlock(); |
ac3a2585 JL |
1009 | |
1010 | if (nf) { | |
b680cb9b JL |
1011 | /* |
1012 | * If the nf is on the LRU then it holds an extra reference | |
1013 | * that must be put if it's removed. It had better not be | |
1014 | * the last one however, since we should hold another. | |
1015 | */ | |
ac3a2585 JL |
1016 | if (nfsd_file_lru_remove(nf)) |
1017 | WARN_ON_ONCE(refcount_dec_and_test(&nf->nf_ref)); | |
65294c1f | 1018 | goto wait_for_construction; |
ac3a2585 | 1019 | } |
65294c1f | 1020 | |
c4c649ab CL |
1021 | new = nfsd_file_alloc(net, inode, need, want_gc); |
1022 | if (!new) { | |
54f7df70 | 1023 | status = nfserr_jukebox; |
c6593366 | 1024 | goto out; |
65294c1f JL |
1025 | } |
1026 | ||
c4c649ab CL |
1027 | rcu_read_lock(); |
1028 | spin_lock(&inode->i_lock); | |
1029 | nf = nfsd_file_lookup_locked(net, cred, inode, need, want_gc); | |
1030 | if (unlikely(nf)) { | |
1031 | spin_unlock(&inode->i_lock); | |
1032 | rcu_read_unlock(); | |
1033 | nfsd_file_slab_free(&new->nf_rcu); | |
1034 | goto wait_for_construction; | |
1035 | } | |
1036 | nf = new; | |
1037 | ret = rhltable_insert(&nfsd_file_rhltable, &nf->nf_rlist, | |
1038 | nfsd_file_rhash_params); | |
1039 | spin_unlock(&inode->i_lock); | |
1040 | rcu_read_unlock(); | |
243a5263 | 1041 | if (likely(ret == 0)) |
65294c1f | 1042 | goto open_file; |
243a5263 | 1043 | |
243a5263 JL |
1044 | if (ret == -EEXIST) |
1045 | goto retry; | |
c4c649ab | 1046 | trace_nfsd_file_insert_err(rqstp, inode, may_flags, ret); |
243a5263 | 1047 | status = nfserr_jukebox; |
c6593366 | 1048 | goto construction_err; |
65294c1f JL |
1049 | |
1050 | wait_for_construction: | |
1051 | wait_on_bit(&nf->nf_flags, NFSD_FILE_PENDING, TASK_UNINTERRUPTIBLE); | |
1052 | ||
1053 | /* Did construction of this file fail? */ | |
1054 | if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) { | |
c4c649ab | 1055 | trace_nfsd_file_cons_err(rqstp, inode, may_flags, nf); |
243a5263 | 1056 | if (!open_retry) { |
28c7d86b | 1057 | status = nfserr_jukebox; |
c6593366 | 1058 | goto construction_err; |
28c7d86b | 1059 | } |
243a5263 | 1060 | open_retry = false; |
65294c1f JL |
1061 | goto retry; |
1062 | } | |
65294c1f JL |
1063 | this_cpu_inc(nfsd_file_cache_hits); |
1064 | ||
23ba98de | 1065 | status = nfserrno(nfsd_open_break_lease(file_inode(nf->nf_file), may_flags)); |
c6593366 JL |
1066 | if (status != nfs_ok) { |
1067 | nfsd_file_put(nf); | |
1068 | nf = NULL; | |
1069 | } | |
1070 | ||
65294c1f JL |
1071 | out: |
1072 | if (status == nfs_ok) { | |
0b3a551f | 1073 | this_cpu_inc(nfsd_file_acquisitions); |
4c475eee | 1074 | nfsd_file_check_write_error(nf); |
65294c1f | 1075 | *pnf = nf; |
65294c1f | 1076 | } |
c4c649ab CL |
1077 | put_cred(cred); |
1078 | trace_nfsd_file_acquire(rqstp, inode, may_flags, nf, status); | |
65294c1f | 1079 | return status; |
54f7df70 | 1080 | |
65294c1f | 1081 | open_file: |
b40a2839 | 1082 | trace_nfsd_file_alloc(nf); |
c4c649ab | 1083 | nf->nf_mark = nfsd_file_mark_find_or_create(nf, inode); |
fb70bf12 | 1084 | if (nf->nf_mark) { |
0b3a551f JL |
1085 | if (file) { |
1086 | get_file(file); | |
1087 | nf->nf_file = file; | |
1088 | status = nfs_ok; | |
1089 | trace_nfsd_file_opened(nf, status); | |
1090 | } else { | |
fb70bf12 CL |
1091 | status = nfsd_open_verified(rqstp, fhp, may_flags, |
1092 | &nf->nf_file); | |
0122e882 | 1093 | trace_nfsd_file_open(nf, status); |
0b3a551f | 1094 | } |
fb70bf12 | 1095 | } else |
65294c1f JL |
1096 | status = nfserr_jukebox; |
1097 | /* | |
1098 | * If construction failed, or we raced with a call to unlink() | |
1099 | * then unhash. | |
1100 | */ | |
c4c649ab | 1101 | if (status != nfs_ok || inode->i_nlink == 0) |
ac3a2585 | 1102 | nfsd_file_unhash(nf); |
b8bea9f6 | 1103 | clear_and_wake_up_bit(NFSD_FILE_PENDING, &nf->nf_flags); |
c6593366 JL |
1104 | if (status == nfs_ok) |
1105 | goto out; | |
1106 | ||
1107 | construction_err: | |
1108 | if (refcount_dec_and_test(&nf->nf_ref)) | |
1109 | nfsd_file_free(nf); | |
1110 | nf = NULL; | |
65294c1f JL |
1111 | goto out; |
1112 | } | |
1113 | ||
4d1ea845 CL |
1114 | /** |
1115 | * nfsd_file_acquire_gc - Get a struct nfsd_file with an open file | |
1116 | * @rqstp: the RPC transaction being executed | |
1117 | * @fhp: the NFS filehandle of the file to be opened | |
1118 | * @may_flags: NFSD_MAY_ settings for the file | |
1119 | * @pnf: OUT: new or found "struct nfsd_file" object | |
1120 | * | |
1121 | * The nfsd_file object returned by this API is reference-counted | |
1122 | * and garbage-collected. The object is retained for a few | |
1123 | * seconds after the final nfsd_file_put() in case the caller | |
1124 | * wants to re-use it. | |
1125 | * | |
c4c649ab CL |
1126 | * Return values: |
1127 | * %nfs_ok - @pnf points to an nfsd_file with its reference | |
1128 | * count boosted. | |
1129 | * | |
1130 | * On error, an nfsstat value in network byte order is returned. | |
4d1ea845 CL |
1131 | */ |
1132 | __be32 | |
1133 | nfsd_file_acquire_gc(struct svc_rqst *rqstp, struct svc_fh *fhp, | |
1134 | unsigned int may_flags, struct nfsd_file **pnf) | |
1135 | { | |
0b3a551f | 1136 | return nfsd_file_do_acquire(rqstp, fhp, may_flags, NULL, pnf, true); |
4d1ea845 CL |
1137 | } |
1138 | ||
fb70bf12 CL |
1139 | /** |
1140 | * nfsd_file_acquire - Get a struct nfsd_file with an open file | |
1141 | * @rqstp: the RPC transaction being executed | |
1142 | * @fhp: the NFS filehandle of the file to be opened | |
1143 | * @may_flags: NFSD_MAY_ settings for the file | |
1144 | * @pnf: OUT: new or found "struct nfsd_file" object | |
1145 | * | |
4d1ea845 CL |
1146 | * The nfsd_file_object returned by this API is reference-counted |
1147 | * but not garbage-collected. The object is unhashed after the | |
1148 | * final nfsd_file_put(). | |
1149 | * | |
c4c649ab CL |
1150 | * Return values: |
1151 | * %nfs_ok - @pnf points to an nfsd_file with its reference | |
1152 | * count boosted. | |
1153 | * | |
1154 | * On error, an nfsstat value in network byte order is returned. | |
fb70bf12 CL |
1155 | */ |
1156 | __be32 | |
1157 | nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, | |
1158 | unsigned int may_flags, struct nfsd_file **pnf) | |
1159 | { | |
0b3a551f | 1160 | return nfsd_file_do_acquire(rqstp, fhp, may_flags, NULL, pnf, false); |
fb70bf12 CL |
1161 | } |
1162 | ||
1163 | /** | |
0b3a551f | 1164 | * nfsd_file_acquire_opened - Get a struct nfsd_file using existing open file |
fb70bf12 CL |
1165 | * @rqstp: the RPC transaction being executed |
1166 | * @fhp: the NFS filehandle of the file just created | |
1167 | * @may_flags: NFSD_MAY_ settings for the file | |
0b3a551f | 1168 | * @file: cached, already-open file (may be NULL) |
fb70bf12 CL |
1169 | * @pnf: OUT: new or found "struct nfsd_file" object |
1170 | * | |
0b3a551f JL |
1171 | * Acquire a nfsd_file object that is not GC'ed. If one doesn't already exist, |
1172 | * and @file is non-NULL, use it to instantiate a new nfsd_file instead of | |
1173 | * opening a new one. | |
4d1ea845 | 1174 | * |
c4c649ab CL |
1175 | * Return values: |
1176 | * %nfs_ok - @pnf points to an nfsd_file with its reference | |
1177 | * count boosted. | |
1178 | * | |
1179 | * On error, an nfsstat value in network byte order is returned. | |
fb70bf12 CL |
1180 | */ |
1181 | __be32 | |
0b3a551f JL |
1182 | nfsd_file_acquire_opened(struct svc_rqst *rqstp, struct svc_fh *fhp, |
1183 | unsigned int may_flags, struct file *file, | |
1184 | struct nfsd_file **pnf) | |
fb70bf12 | 1185 | { |
0b3a551f | 1186 | return nfsd_file_do_acquire(rqstp, fhp, may_flags, file, pnf, false); |
fb70bf12 CL |
1187 | } |
1188 | ||
65294c1f JL |
1189 | /* |
1190 | * Note that fields may be added, removed or reordered in the future. Programs | |
1191 | * scraping this file for info should test the labels to ensure they're | |
1192 | * getting the correct field. | |
1193 | */ | |
1342f9dd | 1194 | int nfsd_file_cache_stats_show(struct seq_file *m, void *v) |
65294c1f | 1195 | { |
1f696e23 | 1196 | unsigned long releases = 0, evictions = 0; |
df2aff52 | 1197 | unsigned long hits = 0, acquisitions = 0; |
ce502f81 | 1198 | unsigned int i, count = 0, buckets = 0; |
904940e9 | 1199 | unsigned long lru = 0, total_age = 0; |
65294c1f | 1200 | |
ce502f81 | 1201 | /* Serialize with server shutdown */ |
65294c1f | 1202 | mutex_lock(&nfsd_mutex); |
c7b824c3 | 1203 | if (test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 1) { |
ce502f81 CL |
1204 | struct bucket_table *tbl; |
1205 | struct rhashtable *ht; | |
1206 | ||
0fd244c1 | 1207 | lru = list_lru_count(&nfsd_file_lru); |
ce502f81 CL |
1208 | |
1209 | rcu_read_lock(); | |
c4c649ab | 1210 | ht = &nfsd_file_rhltable.ht; |
ce502f81 CL |
1211 | count = atomic_read(&ht->nelems); |
1212 | tbl = rht_dereference_rcu(ht->tbl, ht); | |
1213 | buckets = tbl->size; | |
1214 | rcu_read_unlock(); | |
65294c1f JL |
1215 | } |
1216 | mutex_unlock(&nfsd_mutex); | |
1217 | ||
29d4bdbb | 1218 | for_each_possible_cpu(i) { |
65294c1f | 1219 | hits += per_cpu(nfsd_file_cache_hits, i); |
29d4bdbb | 1220 | acquisitions += per_cpu(nfsd_file_acquisitions, i); |
d6329327 | 1221 | releases += per_cpu(nfsd_file_releases, i); |
904940e9 | 1222 | total_age += per_cpu(nfsd_file_total_age, i); |
94660cc1 | 1223 | evictions += per_cpu(nfsd_file_evictions, i); |
29d4bdbb | 1224 | } |
65294c1f | 1225 | |
c4c649ab | 1226 | seq_printf(m, "total inodes: %u\n", count); |
ce502f81 | 1227 | seq_printf(m, "hash buckets: %u\n", buckets); |
0fd244c1 | 1228 | seq_printf(m, "lru entries: %lu\n", lru); |
65294c1f | 1229 | seq_printf(m, "cache hits: %lu\n", hits); |
29d4bdbb | 1230 | seq_printf(m, "acquisitions: %lu\n", acquisitions); |
d6329327 | 1231 | seq_printf(m, "releases: %lu\n", releases); |
94660cc1 | 1232 | seq_printf(m, "evictions: %lu\n", evictions); |
904940e9 CL |
1233 | if (releases) |
1234 | seq_printf(m, "mean age (ms): %ld\n", total_age / releases); | |
1235 | else | |
1236 | seq_printf(m, "mean age (ms): -\n"); | |
65294c1f JL |
1237 | return 0; |
1238 | } |