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-rw-r--r--Documentation/filesystems/caching/fscache.txt81
-rw-r--r--fs/cachefiles/interface.c1
-rw-r--r--fs/cachefiles/rdwr.c6
-rw-r--r--fs/fscache/Kconfig7
-rw-r--r--fs/fscache/Makefile1
-rw-r--r--fs/fscache/cache.c1
-rw-r--r--fs/fscache/cookie.c2
-rw-r--r--fs/fscache/internal.h13
-rw-r--r--fs/fscache/object-list.c432
-rw-r--r--fs/fscache/object.c2
-rw-r--r--fs/fscache/operation.c3
-rw-r--r--fs/fscache/page.c6
-rw-r--r--fs/fscache/proc.c13
-rw-r--r--include/linux/fscache-cache.h13
14 files changed, 578 insertions, 3 deletions
diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt
index 9e94b9491d89..cac09e11ca30 100644
--- a/Documentation/filesystems/caching/fscache.txt
+++ b/Documentation/filesystems/caching/fscache.txt
@@ -299,6 +299,87 @@ proc files.
299 jiffy range covered, and the SECS field the equivalent number of seconds. 299 jiffy range covered, and the SECS field the equivalent number of seconds.
300 300
301 301
302===========
303OBJECT LIST
304===========
305
306If CONFIG_FSCACHE_OBJECT_LIST is enabled, the FS-Cache facility will maintain a
307list of all the objects currently allocated and allow them to be viewed
308through:
309
310 /proc/fs/fscache/objects
311
312This will look something like:
313
314 [root@andromeda ~]# head /proc/fs/fscache/objects
315 OBJECT PARENT STAT CHLDN OPS OOP IPR EX READS EM EV F S | NETFS_COOKIE_DEF TY FL NETFS_DATA OBJECT_KEY, AUX_DATA
316 ======== ======== ==== ===== === === === == ===== == == = = | ================ == == ================ ================
317 17e4b 2 ACTV 0 0 0 0 0 0 7b 4 0 8 | NFS.fh DT 0 ffff88001dd82820 010006017edcf8bbc93b43298fdfbe71e50b57b13a172c0117f38472, e567634700000000000000000000000063f2404a000000000000000000000000c9030000000000000000000063f2404a
318 1693a 2 ACTV 0 0 0 0 0 0 7b 4 0 8 | NFS.fh DT 0 ffff88002db23380 010006017edcf8bbc93b43298fdfbe71e50b57b1e0162c01a2df0ea6, 420ebc4a000000000000000000000000420ebc4a0000000000000000000000000e1801000000000000000000420ebc4a
319
320where the first set of columns before the '|' describe the object:
321
322 COLUMN DESCRIPTION
323 ======= ===============================================================
324 OBJECT Object debugging ID (appears as OBJ%x in some debug messages)
325 PARENT Debugging ID of parent object
326 STAT Object state
327 CHLDN Number of child objects of this object
328 OPS Number of outstanding operations on this object
329 OOP Number of outstanding child object management operations
330 IPR
331 EX Number of outstanding exclusive operations
332 READS Number of outstanding read operations
333 EM Object's event mask
334 EV Events raised on this object
335 F Object flags
336 S Object slow-work work item flags
337
338and the second set of columns describe the object's cookie, if present:
339
340 COLUMN DESCRIPTION
341 =============== =======================================================
342 NETFS_COOKIE_DEF Name of netfs cookie definition
343 TY Cookie type (IX - index, DT - data, hex - special)
344 FL Cookie flags
345 NETFS_DATA Netfs private data stored in the cookie
346 OBJECT_KEY Object key } 1 column, with separating comma
347 AUX_DATA Object aux data } presence may be configured
348
349The data shown may be filtered by attaching the a key to an appropriate keyring
350before viewing the file. Something like:
351
352 keyctl add user fscache:objlist <restrictions> @s
353
354where <restrictions> are a selection of the following letters:
355
356 K Show hexdump of object key (don't show if not given)
357 A Show hexdump of object aux data (don't show if not given)
358
359and the following paired letters:
360
361 C Show objects that have a cookie
362 c Show objects that don't have a cookie
363 B Show objects that are busy
364 b Show objects that aren't busy
365 W Show objects that have pending writes
366 w Show objects that don't have pending writes
367 R Show objects that have outstanding reads
368 r Show objects that don't have outstanding reads
369 S Show objects that have slow work queued
370 s Show objects that don't have slow work queued
371
372If neither side of a letter pair is given, then both are implied. For example:
373
374 keyctl add user fscache:objlist KB @s
375
376shows objects that are busy, and lists their object keys, but does not dump
377their auxiliary data. It also implies "CcWwRrSs", but as 'B' is given, 'b' is
378not implied.
379
380By default all objects and all fields will be shown.
381
382
302========= 383=========
303DEBUGGING 384DEBUGGING
304========= 385=========
diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c
index 431accd475a7..dd7f852746cb 100644
--- a/fs/cachefiles/interface.c
+++ b/fs/cachefiles/interface.c
@@ -331,6 +331,7 @@ static void cachefiles_put_object(struct fscache_object *_object)
331 } 331 }
332 332
333 cache = object->fscache.cache; 333 cache = object->fscache.cache;
334 fscache_object_destroy(&object->fscache);
334 kmem_cache_free(cachefiles_object_jar, object); 335 kmem_cache_free(cachefiles_object_jar, object);
335 fscache_object_destroyed(cache); 336 fscache_object_destroyed(cache);
336 } 337 }
diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c
index a69787e7dd96..3304646dae84 100644
--- a/fs/cachefiles/rdwr.c
+++ b/fs/cachefiles/rdwr.c
@@ -333,7 +333,8 @@ int cachefiles_read_or_alloc_page(struct fscache_retrieval *op,
333 333
334 shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits; 334 shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits;
335 335
336 op->op.flags = FSCACHE_OP_FAST; 336 op->op.flags &= FSCACHE_OP_KEEP_FLAGS;
337 op->op.flags |= FSCACHE_OP_FAST;
337 op->op.processor = cachefiles_read_copier; 338 op->op.processor = cachefiles_read_copier;
338 339
339 pagevec_init(&pagevec, 0); 340 pagevec_init(&pagevec, 0);
@@ -639,7 +640,8 @@ int cachefiles_read_or_alloc_pages(struct fscache_retrieval *op,
639 640
640 pagevec_init(&pagevec, 0); 641 pagevec_init(&pagevec, 0);
641 642
642 op->op.flags = FSCACHE_OP_FAST; 643 op->op.flags &= FSCACHE_OP_KEEP_FLAGS;
644 op->op.flags |= FSCACHE_OP_FAST;
643 op->op.processor = cachefiles_read_copier; 645 op->op.processor = cachefiles_read_copier;
644 646
645 INIT_LIST_HEAD(&backpages); 647 INIT_LIST_HEAD(&backpages);
diff --git a/fs/fscache/Kconfig b/fs/fscache/Kconfig
index 9bbb8ce7bea0..864dac20a242 100644
--- a/fs/fscache/Kconfig
+++ b/fs/fscache/Kconfig
@@ -54,3 +54,10 @@ config FSCACHE_DEBUG
54 enabled by setting bits in /sys/modules/fscache/parameter/debug. 54 enabled by setting bits in /sys/modules/fscache/parameter/debug.
55 55
56 See Documentation/filesystems/caching/fscache.txt for more information. 56 See Documentation/filesystems/caching/fscache.txt for more information.
57
58config FSCACHE_OBJECT_LIST
59 bool "Maintain global object list for debugging purposes"
60 depends on FSCACHE && PROC_FS
61 help
62 Maintain a global list of active fscache objects that can be
63 retrieved through /proc/fs/fscache/objects for debugging purposes
diff --git a/fs/fscache/Makefile b/fs/fscache/Makefile
index 91571b95aacc..6d561531cb36 100644
--- a/fs/fscache/Makefile
+++ b/fs/fscache/Makefile
@@ -15,5 +15,6 @@ fscache-y := \
15fscache-$(CONFIG_PROC_FS) += proc.o 15fscache-$(CONFIG_PROC_FS) += proc.o
16fscache-$(CONFIG_FSCACHE_STATS) += stats.o 16fscache-$(CONFIG_FSCACHE_STATS) += stats.o
17fscache-$(CONFIG_FSCACHE_HISTOGRAM) += histogram.o 17fscache-$(CONFIG_FSCACHE_HISTOGRAM) += histogram.o
18fscache-$(CONFIG_FSCACHE_OBJECT_LIST) += object-list.o
18 19
19obj-$(CONFIG_FSCACHE) := fscache.o 20obj-$(CONFIG_FSCACHE) := fscache.o
diff --git a/fs/fscache/cache.c b/fs/fscache/cache.c
index e21985bbb1fb..724384ef96de 100644
--- a/fs/fscache/cache.c
+++ b/fs/fscache/cache.c
@@ -263,6 +263,7 @@ int fscache_add_cache(struct fscache_cache *cache,
263 spin_lock(&cache->object_list_lock); 263 spin_lock(&cache->object_list_lock);
264 list_add_tail(&ifsdef->cache_link, &cache->object_list); 264 list_add_tail(&ifsdef->cache_link, &cache->object_list);
265 spin_unlock(&cache->object_list_lock); 265 spin_unlock(&cache->object_list_lock);
266 fscache_objlist_add(ifsdef);
266 267
267 /* add the cache's netfs definition index object to the top level index 268 /* add the cache's netfs definition index object to the top level index
268 * cookie as a known backing object */ 269 * cookie as a known backing object */
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c
index 72fd18f6c71f..9b5187328230 100644
--- a/fs/fscache/cookie.c
+++ b/fs/fscache/cookie.c
@@ -349,6 +349,8 @@ static int fscache_attach_object(struct fscache_cookie *cookie,
349 object->cookie = cookie; 349 object->cookie = cookie;
350 atomic_inc(&cookie->usage); 350 atomic_inc(&cookie->usage);
351 hlist_add_head(&object->cookie_link, &cookie->backing_objects); 351 hlist_add_head(&object->cookie_link, &cookie->backing_objects);
352
353 fscache_objlist_add(object);
352 ret = 0; 354 ret = 0;
353 355
354cant_attach_object: 356cant_attach_object:
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
index 1c341304621f..fe02973a9516 100644
--- a/fs/fscache/internal.h
+++ b/fs/fscache/internal.h
@@ -88,11 +88,24 @@ extern int fscache_wait_bit_interruptible(void *);
88/* 88/*
89 * object.c 89 * object.c
90 */ 90 */
91extern const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5];
92
91extern void fscache_withdrawing_object(struct fscache_cache *, 93extern void fscache_withdrawing_object(struct fscache_cache *,
92 struct fscache_object *); 94 struct fscache_object *);
93extern void fscache_enqueue_object(struct fscache_object *); 95extern void fscache_enqueue_object(struct fscache_object *);
94 96
95/* 97/*
98 * object-list.c
99 */
100#ifdef CONFIG_FSCACHE_OBJECT_LIST
101extern const struct file_operations fscache_objlist_fops;
102
103extern void fscache_objlist_add(struct fscache_object *);
104#else
105#define fscache_objlist_add(object) do {} while(0)
106#endif
107
108/*
96 * operation.c 109 * operation.c
97 */ 110 */
98extern int fscache_submit_exclusive_op(struct fscache_object *, 111extern int fscache_submit_exclusive_op(struct fscache_object *,
diff --git a/fs/fscache/object-list.c b/fs/fscache/object-list.c
new file mode 100644
index 000000000000..e590242fa41a
--- /dev/null
+++ b/fs/fscache/object-list.c
@@ -0,0 +1,432 @@
1/* Global fscache object list maintainer and viewer
2 *
3 * Copyright (C) 2009 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
12#define FSCACHE_DEBUG_LEVEL COOKIE
13#include <linux/module.h>
14#include <linux/seq_file.h>
15#include <linux/key.h>
16#include <keys/user-type.h>
17#include "internal.h"
18
19static struct rb_root fscache_object_list;
20static DEFINE_RWLOCK(fscache_object_list_lock);
21
22struct fscache_objlist_data {
23 unsigned long config; /* display configuration */
24#define FSCACHE_OBJLIST_CONFIG_KEY 0x00000001 /* show object keys */
25#define FSCACHE_OBJLIST_CONFIG_AUX 0x00000002 /* show object auxdata */
26#define FSCACHE_OBJLIST_CONFIG_COOKIE 0x00000004 /* show objects with cookies */
27#define FSCACHE_OBJLIST_CONFIG_NOCOOKIE 0x00000008 /* show objects without cookies */
28#define FSCACHE_OBJLIST_CONFIG_BUSY 0x00000010 /* show busy objects */
29#define FSCACHE_OBJLIST_CONFIG_IDLE 0x00000020 /* show idle objects */
30#define FSCACHE_OBJLIST_CONFIG_PENDWR 0x00000040 /* show objects with pending writes */
31#define FSCACHE_OBJLIST_CONFIG_NOPENDWR 0x00000080 /* show objects without pending writes */
32#define FSCACHE_OBJLIST_CONFIG_READS 0x00000100 /* show objects with active reads */
33#define FSCACHE_OBJLIST_CONFIG_NOREADS 0x00000200 /* show objects without active reads */
34#define FSCACHE_OBJLIST_CONFIG_EVENTS 0x00000400 /* show objects with events */
35#define FSCACHE_OBJLIST_CONFIG_NOEVENTS 0x00000800 /* show objects without no events */
36#define FSCACHE_OBJLIST_CONFIG_WORK 0x00001000 /* show objects with slow work */
37#define FSCACHE_OBJLIST_CONFIG_NOWORK 0x00002000 /* show objects without slow work */
38
39 u8 buf[512]; /* key and aux data buffer */
40};
41
42/*
43 * Add an object to the object list
44 * - we use the address of the fscache_object structure as the key into the
45 * tree
46 */
47void fscache_objlist_add(struct fscache_object *obj)
48{
49 struct fscache_object *xobj;
50 struct rb_node **p = &fscache_object_list.rb_node, *parent = NULL;
51
52 write_lock(&fscache_object_list_lock);
53
54 while (*p) {
55 parent = *p;
56 xobj = rb_entry(parent, struct fscache_object, objlist_link);
57
58 if (obj < xobj)
59 p = &(*p)->rb_left;
60 else if (obj > xobj)
61 p = &(*p)->rb_right;
62 else
63 BUG();
64 }
65
66 rb_link_node(&obj->objlist_link, parent, p);
67 rb_insert_color(&obj->objlist_link, &fscache_object_list);
68
69 write_unlock(&fscache_object_list_lock);
70}
71
72/**
73 * fscache_object_destroy - Note that a cache object is about to be destroyed
74 * @object: The object to be destroyed
75 *
76 * Note the imminent destruction and deallocation of a cache object record.
77 */
78void fscache_object_destroy(struct fscache_object *obj)
79{
80 write_lock(&fscache_object_list_lock);
81
82 BUG_ON(RB_EMPTY_ROOT(&fscache_object_list));
83 rb_erase(&obj->objlist_link, &fscache_object_list);
84
85 write_unlock(&fscache_object_list_lock);
86}
87EXPORT_SYMBOL(fscache_object_destroy);
88
89/*
90 * find the object in the tree on or after the specified index
91 */
92static struct fscache_object *fscache_objlist_lookup(loff_t *_pos)
93{
94 struct fscache_object *pobj, *obj, *minobj = NULL;
95 struct rb_node *p;
96 unsigned long pos;
97
98 if (*_pos >= (unsigned long) ERR_PTR(-ENOENT))
99 return NULL;
100 pos = *_pos;
101
102 /* banners (can't represent line 0 by pos 0 as that would involve
103 * returning a NULL pointer) */
104 if (pos == 0)
105 return (struct fscache_object *) ++(*_pos);
106 if (pos < 3)
107 return (struct fscache_object *)pos;
108
109 pobj = (struct fscache_object *)pos;
110 p = fscache_object_list.rb_node;
111 while (p) {
112 obj = rb_entry(p, struct fscache_object, objlist_link);
113 if (pobj < obj) {
114 if (!minobj || minobj > obj)
115 minobj = obj;
116 p = p->rb_left;
117 } else if (pobj > obj) {
118 p = p->rb_right;
119 } else {
120 minobj = obj;
121 break;
122 }
123 obj = NULL;
124 }
125
126 if (!minobj)
127 *_pos = (unsigned long) ERR_PTR(-ENOENT);
128 else if (minobj != obj)
129 *_pos = (unsigned long) minobj;
130 return minobj;
131}
132
133/*
134 * set up the iterator to start reading from the first line
135 */
136static void *fscache_objlist_start(struct seq_file *m, loff_t *_pos)
137 __acquires(&fscache_object_list_lock)
138{
139 read_lock(&fscache_object_list_lock);
140 return fscache_objlist_lookup(_pos);
141}
142
143/*
144 * move to the next line
145 */
146static void *fscache_objlist_next(struct seq_file *m, void *v, loff_t *_pos)
147{
148 (*_pos)++;
149 return fscache_objlist_lookup(_pos);
150}
151
152/*
153 * clean up after reading
154 */
155static void fscache_objlist_stop(struct seq_file *m, void *v)
156 __releases(&fscache_object_list_lock)
157{
158 read_unlock(&fscache_object_list_lock);
159}
160
161/*
162 * display an object
163 */
164static int fscache_objlist_show(struct seq_file *m, void *v)
165{
166 struct fscache_objlist_data *data = m->private;
167 struct fscache_object *obj = v;
168 unsigned long config = data->config;
169 uint16_t keylen, auxlen;
170 char _type[3], *type;
171 bool no_cookie;
172 u8 *buf = data->buf, *p;
173
174 if ((unsigned long) v == 1) {
175 seq_puts(m, "OBJECT PARENT STAT CHLDN OPS OOP IPR EX READS"
176 " EM EV F S"
177 " | NETFS_COOKIE_DEF TY FL NETFS_DATA");
178 if (config & (FSCACHE_OBJLIST_CONFIG_KEY |
179 FSCACHE_OBJLIST_CONFIG_AUX))
180 seq_puts(m, " ");
181 if (config & FSCACHE_OBJLIST_CONFIG_KEY)
182 seq_puts(m, "OBJECT_KEY");
183 if ((config & (FSCACHE_OBJLIST_CONFIG_KEY |
184 FSCACHE_OBJLIST_CONFIG_AUX)) ==
185 (FSCACHE_OBJLIST_CONFIG_KEY | FSCACHE_OBJLIST_CONFIG_AUX))
186 seq_puts(m, ", ");
187 if (config & FSCACHE_OBJLIST_CONFIG_AUX)
188 seq_puts(m, "AUX_DATA");
189 seq_puts(m, "\n");
190 return 0;
191 }
192
193 if ((unsigned long) v == 2) {
194 seq_puts(m, "======== ======== ==== ===== === === === == ====="
195 " == == = ="
196 " | ================ == == ================");
197 if (config & (FSCACHE_OBJLIST_CONFIG_KEY |
198 FSCACHE_OBJLIST_CONFIG_AUX))
199 seq_puts(m, " ================");
200 seq_puts(m, "\n");
201 return 0;
202 }
203
204 /* filter out any unwanted objects */
205#define FILTER(criterion, _yes, _no) \
206 do { \
207 unsigned long yes = FSCACHE_OBJLIST_CONFIG_##_yes; \
208 unsigned long no = FSCACHE_OBJLIST_CONFIG_##_no; \
209 if (criterion) { \
210 if (!(config & yes)) \
211 return 0; \
212 } else { \
213 if (!(config & no)) \
214 return 0; \
215 } \
216 } while(0)
217
218 if (~config) {
219 FILTER(obj->cookie,
220 COOKIE, NOCOOKIE);
221 FILTER(obj->state != FSCACHE_OBJECT_ACTIVE ||
222 obj->n_ops != 0 ||
223 obj->n_obj_ops != 0 ||
224 obj->flags ||
225 !list_empty(&obj->dependents),
226 BUSY, IDLE);
227 FILTER(test_bit(FSCACHE_OBJECT_PENDING_WRITE, &obj->flags),
228 PENDWR, NOPENDWR);
229 FILTER(atomic_read(&obj->n_reads),
230 READS, NOREADS);
231 FILTER(obj->events & obj->event_mask,
232 EVENTS, NOEVENTS);
233 FILTER(obj->work.flags & ~(1UL << SLOW_WORK_VERY_SLOW),
234 WORK, NOWORK);
235 }
236
237 seq_printf(m,
238 "%8x %8x %s %5u %3u %3u %3u %2u %5u %2lx %2lx %1lx %1lx | ",
239 obj->debug_id,
240 obj->parent ? obj->parent->debug_id : -1,
241 fscache_object_states_short[obj->state],
242 obj->n_children,
243 obj->n_ops,
244 obj->n_obj_ops,
245 obj->n_in_progress,
246 obj->n_exclusive,
247 atomic_read(&obj->n_reads),
248 obj->event_mask & FSCACHE_OBJECT_EVENTS_MASK,
249 obj->events,
250 obj->flags,
251 obj->work.flags);
252
253 no_cookie = true;
254 keylen = auxlen = 0;
255 if (obj->cookie) {
256 spin_lock(&obj->lock);
257 if (obj->cookie) {
258 switch (obj->cookie->def->type) {
259 case 0:
260 type = "IX";
261 break;
262 case 1:
263 type = "DT";
264 break;
265 default:
266 sprintf(_type, "%02u",
267 obj->cookie->def->type);
268 type = _type;
269 break;
270 }
271
272 seq_printf(m, "%-16s %s %2lx %16p",
273 obj->cookie->def->name,
274 type,
275 obj->cookie->flags,
276 obj->cookie->netfs_data);
277
278 if (obj->cookie->def->get_key &&
279 config & FSCACHE_OBJLIST_CONFIG_KEY)
280 keylen = obj->cookie->def->get_key(
281 obj->cookie->netfs_data,
282 buf, 400);
283
284 if (obj->cookie->def->get_aux &&
285 config & FSCACHE_OBJLIST_CONFIG_AUX)
286 auxlen = obj->cookie->def->get_aux(
287 obj->cookie->netfs_data,
288 buf + keylen, 512 - keylen);
289
290 no_cookie = false;
291 }
292 spin_unlock(&obj->lock);
293
294 if (!no_cookie && (keylen > 0 || auxlen > 0)) {
295 seq_printf(m, " ");
296 for (p = buf; keylen > 0; keylen--)
297 seq_printf(m, "%02x", *p++);
298 if (auxlen > 0) {
299 if (config & FSCACHE_OBJLIST_CONFIG_KEY)
300 seq_printf(m, ", ");
301 for (; auxlen > 0; auxlen--)
302 seq_printf(m, "%02x", *p++);
303 }
304 }
305 }
306
307 if (no_cookie)
308 seq_printf(m, "<no_cookie>\n");
309 else
310 seq_printf(m, "\n");
311 return 0;
312}
313
314static const struct seq_operations fscache_objlist_ops = {
315 .start = fscache_objlist_start,
316 .stop = fscache_objlist_stop,
317 .next = fscache_objlist_next,
318 .show = fscache_objlist_show,
319};
320
321/*
322 * get the configuration for filtering the list
323 */
324static void fscache_objlist_config(struct fscache_objlist_data *data)
325{
326#ifdef CONFIG_KEYS
327 struct user_key_payload *confkey;
328 unsigned long config;
329 struct key *key;
330 const char *buf;
331 int len;
332
333 key = request_key(&key_type_user, "fscache:objlist", NULL);
334 if (IS_ERR(key))
335 goto no_config;
336
337 config = 0;
338 rcu_read_lock();
339
340 confkey = key->payload.data;
341 buf = confkey->data;
342
343 for (len = confkey->datalen - 1; len >= 0; len--) {
344 switch (buf[len]) {
345 case 'K': config |= FSCACHE_OBJLIST_CONFIG_KEY; break;
346 case 'A': config |= FSCACHE_OBJLIST_CONFIG_AUX; break;
347 case 'C': config |= FSCACHE_OBJLIST_CONFIG_COOKIE; break;
348 case 'c': config |= FSCACHE_OBJLIST_CONFIG_NOCOOKIE; break;
349 case 'B': config |= FSCACHE_OBJLIST_CONFIG_BUSY; break;
350 case 'b': config |= FSCACHE_OBJLIST_CONFIG_IDLE; break;
351 case 'W': config |= FSCACHE_OBJLIST_CONFIG_PENDWR; break;
352 case 'w': config |= FSCACHE_OBJLIST_CONFIG_NOPENDWR; break;
353 case 'R': config |= FSCACHE_OBJLIST_CONFIG_READS; break;
354 case 'r': config |= FSCACHE_OBJLIST_CONFIG_NOREADS; break;
355 case 'S': config |= FSCACHE_OBJLIST_CONFIG_WORK; break;
356 case 's': config |= FSCACHE_OBJLIST_CONFIG_NOWORK; break;
357 }
358 }
359
360 rcu_read_unlock();
361 key_put(key);
362
363 if (!(config & (FSCACHE_OBJLIST_CONFIG_COOKIE | FSCACHE_OBJLIST_CONFIG_NOCOOKIE)))
364 config |= FSCACHE_OBJLIST_CONFIG_COOKIE | FSCACHE_OBJLIST_CONFIG_NOCOOKIE;
365 if (!(config & (FSCACHE_OBJLIST_CONFIG_BUSY | FSCACHE_OBJLIST_CONFIG_IDLE)))
366 config |= FSCACHE_OBJLIST_CONFIG_BUSY | FSCACHE_OBJLIST_CONFIG_IDLE;
367 if (!(config & (FSCACHE_OBJLIST_CONFIG_PENDWR | FSCACHE_OBJLIST_CONFIG_NOPENDWR)))
368 config |= FSCACHE_OBJLIST_CONFIG_PENDWR | FSCACHE_OBJLIST_CONFIG_NOPENDWR;
369 if (!(config & (FSCACHE_OBJLIST_CONFIG_READS | FSCACHE_OBJLIST_CONFIG_NOREADS)))
370 config |= FSCACHE_OBJLIST_CONFIG_READS | FSCACHE_OBJLIST_CONFIG_NOREADS;
371 if (!(config & (FSCACHE_OBJLIST_CONFIG_EVENTS | FSCACHE_OBJLIST_CONFIG_NOEVENTS)))
372 config |= FSCACHE_OBJLIST_CONFIG_EVENTS | FSCACHE_OBJLIST_CONFIG_NOEVENTS;
373 if (!(config & (FSCACHE_OBJLIST_CONFIG_WORK | FSCACHE_OBJLIST_CONFIG_NOWORK)))
374 config |= FSCACHE_OBJLIST_CONFIG_WORK | FSCACHE_OBJLIST_CONFIG_NOWORK;
375
376 data->config = config;
377 return;
378
379no_config:
380#endif
381 data->config = ULONG_MAX;
382}
383
384/*
385 * open "/proc/fs/fscache/objects" to provide a list of active objects
386 * - can be configured by a user-defined key added to the caller's keyrings
387 */
388static int fscache_objlist_open(struct inode *inode, struct file *file)
389{
390 struct fscache_objlist_data *data;
391 struct seq_file *m;
392 int ret;
393
394 ret = seq_open(file, &fscache_objlist_ops);
395 if (ret < 0)
396 return ret;
397
398 m = file->private_data;
399
400 /* buffer for key extraction */
401 data = kmalloc(sizeof(struct fscache_objlist_data), GFP_KERNEL);
402 if (!data) {
403 seq_release(inode, file);
404 return -ENOMEM;
405 }
406
407 /* get the configuration key */
408 fscache_objlist_config(data);
409
410 m->private = data;
411 return 0;
412}
413
414/*
415 * clean up on close
416 */
417static int fscache_objlist_release(struct inode *inode, struct file *file)
418{
419 struct seq_file *m = file->private_data;
420
421 kfree(m->private);
422 m->private = NULL;
423 return seq_release(inode, file);
424}
425
426const struct file_operations fscache_objlist_fops = {
427 .owner = THIS_MODULE,
428 .open = fscache_objlist_open,
429 .read = seq_read,
430 .llseek = seq_lseek,
431 .release = fscache_objlist_release,
432};
diff --git a/fs/fscache/object.c b/fs/fscache/object.c
index 615b63dd9ecc..ad1644f073bd 100644
--- a/fs/fscache/object.c
+++ b/fs/fscache/object.c
@@ -34,7 +34,7 @@ const char *fscache_object_states[FSCACHE_OBJECT__NSTATES] = {
34}; 34};
35EXPORT_SYMBOL(fscache_object_states); 35EXPORT_SYMBOL(fscache_object_states);
36 36
37static const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5] = { 37const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5] = {
38 [FSCACHE_OBJECT_INIT] = "INIT", 38 [FSCACHE_OBJECT_INIT] = "INIT",
39 [FSCACHE_OBJECT_LOOKING_UP] = "LOOK", 39 [FSCACHE_OBJECT_LOOKING_UP] = "LOOK",
40 [FSCACHE_OBJECT_CREATING] = "CRTN", 40 [FSCACHE_OBJECT_CREATING] = "CRTN",
diff --git a/fs/fscache/operation.c b/fs/fscache/operation.c
index 91bbe6f0377c..09e43b6e822f 100644
--- a/fs/fscache/operation.c
+++ b/fs/fscache/operation.c
@@ -322,6 +322,9 @@ void fscache_put_operation(struct fscache_operation *op)
322 322
323 object = op->object; 323 object = op->object;
324 324
325 if (test_bit(FSCACHE_OP_DEC_READ_CNT, &op->flags))
326 atomic_dec(&object->n_reads);
327
325 /* now... we may get called with the object spinlock held, so we 328 /* now... we may get called with the object spinlock held, so we
326 * complete the cleanup here only if we can immediately acquire the 329 * complete the cleanup here only if we can immediately acquire the
327 * lock, and defer it otherwise */ 330 * lock, and defer it otherwise */
diff --git a/fs/fscache/page.c b/fs/fscache/page.c
index e8bbc395cef6..c5973e38ce39 100644
--- a/fs/fscache/page.c
+++ b/fs/fscache/page.c
@@ -275,6 +275,9 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
275 275
276 ASSERTCMP(object->state, >, FSCACHE_OBJECT_LOOKING_UP); 276 ASSERTCMP(object->state, >, FSCACHE_OBJECT_LOOKING_UP);
277 277
278 atomic_inc(&object->n_reads);
279 set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags);
280
278 if (fscache_submit_op(object, &op->op) < 0) 281 if (fscache_submit_op(object, &op->op) < 0)
279 goto nobufs_unlock; 282 goto nobufs_unlock;
280 spin_unlock(&cookie->lock); 283 spin_unlock(&cookie->lock);
@@ -386,6 +389,9 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
386 object = hlist_entry(cookie->backing_objects.first, 389 object = hlist_entry(cookie->backing_objects.first,
387 struct fscache_object, cookie_link); 390 struct fscache_object, cookie_link);
388 391
392 atomic_inc(&object->n_reads);
393 set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags);
394
389 if (fscache_submit_op(object, &op->op) < 0) 395 if (fscache_submit_op(object, &op->op) < 0)
390 goto nobufs_unlock; 396 goto nobufs_unlock;
391 spin_unlock(&cookie->lock); 397 spin_unlock(&cookie->lock);
diff --git a/fs/fscache/proc.c b/fs/fscache/proc.c
index beeab44bc31a..1d9e4951a597 100644
--- a/fs/fscache/proc.c
+++ b/fs/fscache/proc.c
@@ -37,10 +37,20 @@ int __init fscache_proc_init(void)
37 goto error_histogram; 37 goto error_histogram;
38#endif 38#endif
39 39
40#ifdef CONFIG_FSCACHE_OBJECT_LIST
41 if (!proc_create("fs/fscache/objects", S_IFREG | 0444, NULL,
42 &fscache_objlist_fops))
43 goto error_objects;
44#endif
45
40 _leave(" = 0"); 46 _leave(" = 0");
41 return 0; 47 return 0;
42 48
49#ifdef CONFIG_FSCACHE_OBJECT_LIST
50error_objects:
51#endif
43#ifdef CONFIG_FSCACHE_HISTOGRAM 52#ifdef CONFIG_FSCACHE_HISTOGRAM
53 remove_proc_entry("fs/fscache/histogram", NULL);
44error_histogram: 54error_histogram:
45#endif 55#endif
46#ifdef CONFIG_FSCACHE_STATS 56#ifdef CONFIG_FSCACHE_STATS
@@ -58,6 +68,9 @@ error_dir:
58 */ 68 */
59void fscache_proc_cleanup(void) 69void fscache_proc_cleanup(void)
60{ 70{
71#ifdef CONFIG_FSCACHE_OBJECT_LIST
72 remove_proc_entry("fs/fscache/objects", NULL);
73#endif
61#ifdef CONFIG_FSCACHE_HISTOGRAM 74#ifdef CONFIG_FSCACHE_HISTOGRAM
62 remove_proc_entry("fs/fscache/histogram", NULL); 75 remove_proc_entry("fs/fscache/histogram", NULL);
63#endif 76#endif
diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h
index 7a9847ccd192..184cbdfbcc99 100644
--- a/include/linux/fscache-cache.h
+++ b/include/linux/fscache-cache.h
@@ -91,6 +91,8 @@ struct fscache_operation {
91#define FSCACHE_OP_WAITING 4 /* cleared when op is woken */ 91#define FSCACHE_OP_WAITING 4 /* cleared when op is woken */
92#define FSCACHE_OP_EXCLUSIVE 5 /* exclusive op, other ops must wait */ 92#define FSCACHE_OP_EXCLUSIVE 5 /* exclusive op, other ops must wait */
93#define FSCACHE_OP_DEAD 6 /* op is now dead */ 93#define FSCACHE_OP_DEAD 6 /* op is now dead */
94#define FSCACHE_OP_DEC_READ_CNT 7 /* decrement object->n_reads on destruction */
95#define FSCACHE_OP_KEEP_FLAGS 0xc0 /* flags to keep when repurposing an op */
94 96
95 atomic_t usage; 97 atomic_t usage;
96 unsigned debug_id; /* debugging ID */ 98 unsigned debug_id; /* debugging ID */
@@ -357,6 +359,7 @@ struct fscache_object {
357 int n_obj_ops; /* number of object ops outstanding on object */ 359 int n_obj_ops; /* number of object ops outstanding on object */
358 int n_in_progress; /* number of ops in progress */ 360 int n_in_progress; /* number of ops in progress */
359 int n_exclusive; /* number of exclusive ops queued */ 361 int n_exclusive; /* number of exclusive ops queued */
362 atomic_t n_reads; /* number of read ops in progress */
360 spinlock_t lock; /* state and operations lock */ 363 spinlock_t lock; /* state and operations lock */
361 364
362 unsigned long lookup_jif; /* time at which lookup started */ 365 unsigned long lookup_jif; /* time at which lookup started */
@@ -370,6 +373,7 @@ struct fscache_object {
370#define FSCACHE_OBJECT_EV_RELEASE 4 /* T if netfs requested object release */ 373#define FSCACHE_OBJECT_EV_RELEASE 4 /* T if netfs requested object release */
371#define FSCACHE_OBJECT_EV_RETIRE 5 /* T if netfs requested object retirement */ 374#define FSCACHE_OBJECT_EV_RETIRE 5 /* T if netfs requested object retirement */
372#define FSCACHE_OBJECT_EV_WITHDRAW 6 /* T if cache requested object withdrawal */ 375#define FSCACHE_OBJECT_EV_WITHDRAW 6 /* T if cache requested object withdrawal */
376#define FSCACHE_OBJECT_EVENTS_MASK 0x7f /* mask of all events*/
373 377
374 unsigned long flags; 378 unsigned long flags;
375#define FSCACHE_OBJECT_LOCK 0 /* T if object is busy being processed */ 379#define FSCACHE_OBJECT_LOCK 0 /* T if object is busy being processed */
@@ -385,6 +389,9 @@ struct fscache_object {
385 struct list_head dependents; /* FIFO of dependent objects */ 389 struct list_head dependents; /* FIFO of dependent objects */
386 struct list_head dep_link; /* link in parent's dependents list */ 390 struct list_head dep_link; /* link in parent's dependents list */
387 struct list_head pending_ops; /* unstarted operations on this object */ 391 struct list_head pending_ops; /* unstarted operations on this object */
392#ifdef CONFIG_FSCACHE_OBJECT_LIST
393 struct rb_node objlist_link; /* link in global object list */
394#endif
388 pgoff_t store_limit; /* current storage limit */ 395 pgoff_t store_limit; /* current storage limit */
389}; 396};
390 397
@@ -434,6 +441,12 @@ void fscache_object_init(struct fscache_object *object,
434extern void fscache_object_lookup_negative(struct fscache_object *object); 441extern void fscache_object_lookup_negative(struct fscache_object *object);
435extern void fscache_obtained_object(struct fscache_object *object); 442extern void fscache_obtained_object(struct fscache_object *object);
436 443
444#ifdef CONFIG_FSCACHE_OBJECT_LIST
445extern void fscache_object_destroy(struct fscache_object *object);
446#else
447#define fscache_object_destroy(object) do {} while(0)
448#endif
449
437/** 450/**
438 * fscache_object_destroyed - Note destruction of an object in a cache 451 * fscache_object_destroyed - Note destruction of an object in a cache
439 * @cache: The cache from which the object came 452 * @cache: The cache from which the object came