diff --git a/Documentation/filesystems/caching/backend-api.txt b/Documentation/filesystems/caching/backend-api.txt
index 277d1e810670..c0bd5677271b 100644
--- a/Documentation/filesystems/caching/backend-api.txt
+++ b/Documentation/filesystems/caching/backend-api.txt
@@ -676,6 +676,29 @@ FS-Cache provides some utilities that a cache backend may make use of:
as possible.
+ (*) Indicate that a stale object was found and discarded:
+
+ void fscache_object_retrying_stale(struct fscache_object *object);
+
+ This is called to indicate that the lookup procedure found an object in
+ the cache that the netfs decided was stale. The object has been
+ discarded from the cache and the lookup will be performed again.
+
+
+ (*) Indicate that the caching backend killed an object:
+
+ void fscache_object_mark_killed(struct fscache_object *object,
+ enum fscache_why_object_killed why);
+
+ This is called to indicate that the cache backend preemptively killed an
+ object. The why parameter should be set to indicate the reason:
+
+ FSCACHE_OBJECT_IS_STALE - the object was stale and needs discarding.
+ FSCACHE_OBJECT_NO_SPACE - there was insufficient cache space
+ FSCACHE_OBJECT_WAS_RETIRED - the object was retired when relinquished.
+ FSCACHE_OBJECT_WAS_CULLED - the object was culled to make space.
+
+
(*) Get and release references on a retrieval record:
void fscache_get_retrieval(struct fscache_retrieval *op);
diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt
index 770267af5b3e..50f0a5757f48 100644
--- a/Documentation/filesystems/caching/fscache.txt
+++ b/Documentation/filesystems/caching/fscache.txt
@@ -284,8 +284,9 @@ proc files.
enq=N Number of times async ops queued for processing
can=N Number of async ops cancelled
rej=N Number of async ops rejected due to object lookup/create failure
+ ini=N Number of async ops initialised
dfr=N Number of async ops queued for deferred release
- rel=N Number of async ops released
+ rel=N Number of async ops released (should equal ini=N when idle)
gc=N Number of deferred-release async ops garbage collected
CacheOp alo=N Number of in-progress alloc_object() cache ops
luo=N Number of in-progress lookup_object() cache ops
@@ -303,6 +304,10 @@ proc files.
wrp=N Number of in-progress write_page() cache ops
ucp=N Number of in-progress uncache_page() cache ops
dsp=N Number of in-progress dissociate_pages() cache ops
+ CacheEv nsp=N Number of object lookups/creations rejected due to lack of space
+ stl=N Number of stale objects deleted
+ rtr=N Number of objects retired when relinquished
+ cul=N Number of objects culled
(*) /proc/fs/fscache/histogram
diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h
index 8c52472d2efa..aecd0859eacb 100644
--- a/fs/cachefiles/internal.h
+++ b/fs/cachefiles/internal.h
@@ -43,7 +43,6 @@ struct cachefiles_object {
loff_t i_size; /* object size */
unsigned long flags;
#define CACHEFILES_OBJECT_ACTIVE 0 /* T if marked active */
-#define CACHEFILES_OBJECT_BURIED 1 /* T if preemptively buried */
atomic_t usage; /* object usage count */
uint8_t type; /* object type */
uint8_t new; /* T if object new */
diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index ab857ab9f40d..fc1056f5c96a 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -97,7 +97,8 @@ static noinline void cachefiles_printk_object(struct cachefiles_object *object,
* call vfs_unlink(), vfs_rmdir() or vfs_rename()
*/
static void cachefiles_mark_object_buried(struct cachefiles_cache *cache,
- struct dentry *dentry)
+ struct dentry *dentry,
+ enum fscache_why_object_killed why)
{
struct cachefiles_object *object;
struct rb_node *p;
@@ -132,8 +133,9 @@ found_dentry:
pr_err("\n");
pr_err("Error: Can't preemptively bury live object\n");
cachefiles_printk_object(object, NULL);
- } else if (test_and_set_bit(CACHEFILES_OBJECT_BURIED, &object->flags)) {
- pr_err("Error: Object already preemptively buried\n");
+ } else {
+ if (why != FSCACHE_OBJECT_IS_STALE)
+ fscache_object_mark_killed(&object->fscache, why);
}
write_unlock(&cache->active_lock);
@@ -265,7 +267,8 @@ requeue:
static int cachefiles_bury_object(struct cachefiles_cache *cache,
struct dentry *dir,
struct dentry *rep,
- bool preemptive)
+ bool preemptive,
+ enum fscache_why_object_killed why)
{
struct dentry *grave, *trap;
struct path path, path_to_graveyard;
@@ -289,7 +292,7 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache,
ret = vfs_unlink(d_inode(dir), rep, NULL);
if (preemptive)
- cachefiles_mark_object_buried(cache, rep);
+ cachefiles_mark_object_buried(cache, rep, why);
}
mutex_unlock(&d_inode(dir)->i_mutex);
@@ -394,7 +397,7 @@ try_again:
"Rename failed with error %d", ret);
if (preemptive)
- cachefiles_mark_object_buried(cache, rep);
+ cachefiles_mark_object_buried(cache, rep, why);
}
unlock_rename(cache->graveyard, dir);
@@ -422,7 +425,7 @@ int cachefiles_delete_object(struct cachefiles_cache *cache,
mutex_lock_nested(&d_inode(dir)->i_mutex, I_MUTEX_PARENT);
- if (test_bit(CACHEFILES_OBJECT_BURIED, &object->flags)) {
+ if (test_bit(FSCACHE_OBJECT_KILLED_BY_CACHE, &object->fscache.flags)) {
/* object allocation for the same key preemptively deleted this
* object's file so that it could create its own file */
_debug("object preemptively buried");
@@ -433,7 +436,8 @@ int cachefiles_delete_object(struct cachefiles_cache *cache,
* may have been renamed */
if (dir == object->dentry->d_parent) {
ret = cachefiles_bury_object(cache, dir,
- object->dentry, false);
+ object->dentry, false,
+ FSCACHE_OBJECT_WAS_RETIRED);
} else {
/* it got moved, presumably by cachefilesd culling it,
* so it's no longer in the key path and we can ignore
@@ -522,7 +526,7 @@ lookup_again:
if (d_is_negative(next)) {
ret = cachefiles_has_space(cache, 1, 0);
if (ret < 0)
- goto create_error;
+ goto no_space_error;
path.dentry = dir;
ret = security_path_mkdir(&path, next, 0);
@@ -551,7 +555,7 @@ lookup_again:
if (d_is_negative(next)) {
ret = cachefiles_has_space(cache, 1, 0);
if (ret < 0)
- goto create_error;
+ goto no_space_error;
path.dentry = dir;
ret = security_path_mknod(&path, next, S_IFREG, 0);
@@ -602,7 +606,8 @@ lookup_again:
* mutex) */
object->dentry = NULL;
- ret = cachefiles_bury_object(cache, dir, next, true);
+ ret = cachefiles_bury_object(cache, dir, next, true,
+ FSCACHE_OBJECT_IS_STALE);
dput(next);
next = NULL;
@@ -610,6 +615,7 @@ lookup_again:
goto delete_error;
_debug("redo lookup");
+ fscache_object_retrying_stale(&object->fscache);
goto lookup_again;
}
}
@@ -662,6 +668,8 @@ lookup_again:
_leave(" = 0 [%lu]", d_backing_inode(object->dentry)->i_ino);
return 0;
+no_space_error:
+ fscache_object_mark_killed(&object->fscache, FSCACHE_OBJECT_NO_SPACE);
create_error:
_debug("create error %d", ret);
if (ret == -EIO)
@@ -927,7 +935,8 @@ int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir,
/* actually remove the victim (drops the dir mutex) */
_debug("bury");
- ret = cachefiles_bury_object(cache, dir, victim, false);
+ ret = cachefiles_bury_object(cache, dir, victim, false,
+ FSCACHE_OBJECT_WAS_CULLED);
if (ret < 0)
goto error;
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c
index 89acec742e0b..d403c69bee08 100644
--- a/fs/fscache/cookie.c
+++ b/fs/fscache/cookie.c
@@ -327,7 +327,8 @@ static int fscache_alloc_object(struct fscache_cache *cache,
object_already_extant:
ret = -ENOBUFS;
- if (fscache_object_is_dead(object)) {
+ if (fscache_object_is_dying(object) ||
+ fscache_cache_is_broken(object)) {
spin_unlock(&cookie->lock);
goto error;
}
@@ -671,7 +672,7 @@ int __fscache_check_consistency(struct fscache_cookie *cookie)
if (!op)
return -ENOMEM;
- fscache_operation_init(op, NULL, NULL);
+ fscache_operation_init(op, NULL, NULL, NULL);
op->flags = FSCACHE_OP_MYTHREAD |
(1 << FSCACHE_OP_WAITING) |
(1 << FSCACHE_OP_UNUSE_COOKIE);
@@ -695,8 +696,7 @@ int __fscache_check_consistency(struct fscache_cookie *cookie)
/* the work queue now carries its own ref on the object */
spin_unlock(&cookie->lock);
- ret = fscache_wait_for_operation_activation(object, op,
- NULL, NULL, NULL);
+ ret = fscache_wait_for_operation_activation(object, op, NULL, NULL);
if (ret == 0) {
/* ask the cache to honour the operation */
ret = object->cache->ops->check_consistency(op);
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
index 7872a62ef30c..97ec45110957 100644
--- a/fs/fscache/internal.h
+++ b/fs/fscache/internal.h
@@ -124,8 +124,7 @@ extern int fscache_submit_exclusive_op(struct fscache_object *,
struct fscache_operation *);
extern int fscache_submit_op(struct fscache_object *,
struct fscache_operation *);
-extern int fscache_cancel_op(struct fscache_operation *,
- void (*)(struct fscache_operation *));
+extern int fscache_cancel_op(struct fscache_operation *, bool);
extern void fscache_cancel_all_ops(struct fscache_object *);
extern void fscache_abort_object(struct fscache_object *);
extern void fscache_start_operations(struct fscache_object *);
@@ -138,8 +137,7 @@ extern int fscache_wait_for_deferred_lookup(struct fscache_cookie *);
extern int fscache_wait_for_operation_activation(struct fscache_object *,
struct fscache_operation *,
atomic_t *,
- atomic_t *,
- void (*)(struct fscache_operation *));
+ atomic_t *);
extern void fscache_invalidate_writes(struct fscache_cookie *);
/*
@@ -164,6 +162,7 @@ extern atomic_t fscache_n_op_pend;
extern atomic_t fscache_n_op_run;
extern atomic_t fscache_n_op_enqueue;
extern atomic_t fscache_n_op_deferred_release;
+extern atomic_t fscache_n_op_initialised;
extern atomic_t fscache_n_op_release;
extern atomic_t fscache_n_op_gc;
extern atomic_t fscache_n_op_cancelled;
@@ -271,6 +270,11 @@ extern atomic_t fscache_n_cop_write_page;
extern atomic_t fscache_n_cop_uncache_page;
extern atomic_t fscache_n_cop_dissociate_pages;
+extern atomic_t fscache_n_cache_no_space_reject;
+extern atomic_t fscache_n_cache_stale_objects;
+extern atomic_t fscache_n_cache_retired_objects;
+extern atomic_t fscache_n_cache_culled_objects;
+
static inline void fscache_stat(atomic_t *stat)
{
atomic_inc(stat);
diff --git a/fs/fscache/object.c b/fs/fscache/object.c
index da032daf0e0d..9e792e30f4db 100644
--- a/fs/fscache/object.c
+++ b/fs/fscache/object.c
@@ -327,6 +327,17 @@ void fscache_object_init(struct fscache_object *object,
}
EXPORT_SYMBOL(fscache_object_init);
+/*
+ * Mark the object as no longer being live, making sure that we synchronise
+ * against op submission.
+ */
+static inline void fscache_mark_object_dead(struct fscache_object *object)
+{
+ spin_lock(&object->lock);
+ clear_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
+ spin_unlock(&object->lock);
+}
+
/*
* Abort object initialisation before we start it.
*/
@@ -610,6 +621,8 @@ static const struct fscache_state *fscache_lookup_failure(struct fscache_object
object->cache->ops->lookup_complete(object);
fscache_stat_d(&fscache_n_cop_lookup_complete);
+ set_bit(FSCACHE_OBJECT_KILLED_BY_CACHE, &object->flags);
+
cookie = object->cookie;
set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
if (test_and_clear_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags))
@@ -629,7 +642,7 @@ static const struct fscache_state *fscache_kill_object(struct fscache_object *ob
_enter("{OBJ%x,%d,%d},%d",
object->debug_id, object->n_ops, object->n_children, event);
- clear_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
+ fscache_mark_object_dead(object);
object->oob_event_mask = 0;
if (list_empty(&object->dependents) &&
@@ -948,7 +961,8 @@ static const struct fscache_state *_fscache_invalidate_object(struct fscache_obj
if (!op)
goto nomem;
- fscache_operation_init(op, object->cache->ops->invalidate_object, NULL);
+ fscache_operation_init(op, object->cache->ops->invalidate_object,
+ NULL, NULL);
op->flags = FSCACHE_OP_ASYNC |
(1 << FSCACHE_OP_EXCLUSIVE) |
(1 << FSCACHE_OP_UNUSE_COOKIE);
@@ -974,13 +988,13 @@ static const struct fscache_state *_fscache_invalidate_object(struct fscache_obj
return transit_to(UPDATE_OBJECT);
nomem:
- clear_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
+ fscache_mark_object_dead(object);
fscache_unuse_cookie(object);
_leave(" [ENOMEM]");
return transit_to(KILL_OBJECT);
submit_op_failed:
- clear_bit(FSCACHE_OBJECT_IS_LIVE, &object->flags);
+ fscache_mark_object_dead(object);
spin_unlock(&cookie->lock);
fscache_unuse_cookie(object);
kfree(op);
@@ -1016,3 +1030,50 @@ static const struct fscache_state *fscache_update_object(struct fscache_object *
_leave("");
return transit_to(WAIT_FOR_CMD);
}
+
+/**
+ * fscache_object_retrying_stale - Note retrying stale object
+ * @object: The object that will be retried
+ *
+ * Note that an object lookup found an on-disk object that was adjudged to be
+ * stale and has been deleted. The lookup will be retried.
+ */
+void fscache_object_retrying_stale(struct fscache_object *object)
+{
+ fscache_stat(&fscache_n_cache_no_space_reject);
+}
+EXPORT_SYMBOL(fscache_object_retrying_stale);
+
+/**
+ * fscache_object_mark_killed - Note that an object was killed
+ * @object: The object that was culled
+ * @why: The reason the object was killed.
+ *
+ * Note that an object was killed. Returns true if the object was
+ * already marked killed, false if it wasn't.
+ */
+void fscache_object_mark_killed(struct fscache_object *object,
+ enum fscache_why_object_killed why)
+{
+ if (test_and_set_bit(FSCACHE_OBJECT_KILLED_BY_CACHE, &object->flags)) {
+ pr_err("Error: Object already killed by cache [%s]\n",
+ object->cache->identifier);
+ return;
+ }
+
+ switch (why) {
+ case FSCACHE_OBJECT_NO_SPACE:
+ fscache_stat(&fscache_n_cache_no_space_reject);
+ break;
+ case FSCACHE_OBJECT_IS_STALE:
+ fscache_stat(&fscache_n_cache_stale_objects);
+ break;
+ case FSCACHE_OBJECT_WAS_RETIRED:
+ fscache_stat(&fscache_n_cache_retired_objects);
+ break;
+ case FSCACHE_OBJECT_WAS_CULLED:
+ fscache_stat(&fscache_n_cache_culled_objects);
+ break;
+ }
+}
+EXPORT_SYMBOL(fscache_object_mark_killed);
diff --git a/fs/fscache/operation.c b/fs/fscache/operation.c
index e7b87a0e5185..de67745e1cd7 100644
--- a/fs/fscache/operation.c
+++ b/fs/fscache/operation.c
@@ -20,6 +20,35 @@
atomic_t fscache_op_debug_id;
EXPORT_SYMBOL(fscache_op_debug_id);
+static void fscache_operation_dummy_cancel(struct fscache_operation *op)
+{
+}
+
+/**
+ * fscache_operation_init - Do basic initialisation of an operation
+ * @op: The operation to initialise
+ * @release: The release function to assign
+ *
+ * Do basic initialisation of an operation. The caller must still set flags,
+ * object and processor if needed.
+ */
+void fscache_operation_init(struct fscache_operation *op,
+ fscache_operation_processor_t processor,
+ fscache_operation_cancel_t cancel,
+ fscache_operation_release_t release)
+{
+ INIT_WORK(&op->work, fscache_op_work_func);
+ atomic_set(&op->usage, 1);
+ op->state = FSCACHE_OP_ST_INITIALISED;
+ op->debug_id = atomic_inc_return(&fscache_op_debug_id);
+ op->processor = processor;
+ op->cancel = cancel ?: fscache_operation_dummy_cancel;
+ op->release = release;
+ INIT_LIST_HEAD(&op->pend_link);
+ fscache_stat(&fscache_n_op_initialised);
+}
+EXPORT_SYMBOL(fscache_operation_init);
+
/**
* fscache_enqueue_operation - Enqueue an operation for processing
* @op: The operation to enqueue
@@ -75,69 +104,6 @@ static void fscache_run_op(struct fscache_object *object,
fscache_stat(&fscache_n_op_run);
}
-/*
- * submit an exclusive operation for an object
- * - other ops are excluded from running simultaneously with this one
- * - this gets any extra refs it needs on an op
- */
-int fscache_submit_exclusive_op(struct fscache_object *object,
- struct fscache_operation *op)
-{
- int ret;
-
- _enter("{OBJ%x OP%x},", object->debug_id, op->debug_id);
-
- ASSERTCMP(op->state, ==, FSCACHE_OP_ST_INITIALISED);
- ASSERTCMP(atomic_read(&op->usage), >, 0);
-
- spin_lock(&object->lock);
- ASSERTCMP(object->n_ops, >=, object->n_in_progress);
- ASSERTCMP(object->n_ops, >=, object->n_exclusive);
- ASSERT(list_empty(&op->pend_link));
-
- op->state = FSCACHE_OP_ST_PENDING;
- if (fscache_object_is_active(object)) {
- op->object = object;
- object->n_ops++;
- object->n_exclusive++; /* reads and writes must wait */
-
- if (object->n_in_progress > 0) {
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- } else if (!list_empty(&object->pending_ops)) {
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- fscache_start_operations(object);
- } else {
- ASSERTCMP(object->n_in_progress, ==, 0);
- fscache_run_op(object, op);
- }
-
- /* need to issue a new write op after this */
- clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags);
- ret = 0;
- } else if (test_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)) {
- op->object = object;
- object->n_ops++;
- object->n_exclusive++; /* reads and writes must wait */
- atomic_inc(&op->usage);
- list_add_tail(&op->pend_link, &object->pending_ops);
- fscache_stat(&fscache_n_op_pend);
- ret = 0;
- } else {
- /* If we're in any other state, there must have been an I/O
- * error of some nature.
- */
- ASSERT(test_bit(FSCACHE_IOERROR, &object->cache->flags));
- ret = -EIO;
- }
-
- spin_unlock(&object->lock);
- return ret;
-}
-
/*
* report an unexpected submission
*/
@@ -175,6 +141,87 @@ static void fscache_report_unexpected_submission(struct fscache_object *object,
dump_stack();
}
+/*
+ * submit an exclusive operation for an object
+ * - other ops are excluded from running simultaneously with this one
+ * - this gets any extra refs it needs on an op
+ */
+int fscache_submit_exclusive_op(struct fscache_object *object,
+ struct fscache_operation *op)
+{
+ const struct fscache_state *ostate;
+ unsigned long flags;
+ int ret;
+
+ _enter("{OBJ%x OP%x},", object->debug_id, op->debug_id);
+
+ ASSERTCMP(op->state, ==, FSCACHE_OP_ST_INITIALISED);
+ ASSERTCMP(atomic_read(&op->usage), >, 0);
+
+ spin_lock(&object->lock);
+ ASSERTCMP(object->n_ops, >=, object->n_in_progress);
+ ASSERTCMP(object->n_ops, >=, object->n_exclusive);
+ ASSERT(list_empty(&op->pend_link));
+
+ ostate = object->state;
+ smp_rmb();
+
+ op->state = FSCACHE_OP_ST_PENDING;
+ flags = READ_ONCE(object->flags);
+ if (unlikely(!(flags & BIT(FSCACHE_OBJECT_IS_LIVE)))) {
+ fscache_stat(&fscache_n_op_rejected);
+ op->cancel(op);
+ op->state = FSCACHE_OP_ST_CANCELLED;
+ ret = -ENOBUFS;
+ } else if (unlikely(fscache_cache_is_broken(object))) {
+ op->cancel(op);
+ op->state = FSCACHE_OP_ST_CANCELLED;
+ ret = -EIO;
+ } else if (flags & BIT(FSCACHE_OBJECT_IS_AVAILABLE)) {
+ op->object = object;
+ object->n_ops++;
+ object->n_exclusive++; /* reads and writes must wait */
+
+ if (object->n_in_progress > 0) {
+ atomic_inc(&op->usage);
+ list_add_tail(&op->pend_link, &object->pending_ops);
+ fscache_stat(&fscache_n_op_pend);
+ } else if (!list_empty(&object->pending_ops)) {
+ atomic_inc(&op->usage);
+ list_add_tail(&op->pend_link, &object->pending_ops);
+ fscache_stat(&fscache_n_op_pend);
+ fscache_start_operations(object);
+ } else {
+ ASSERTCMP(object->n_in_progress, ==, 0);
+ fscache_run_op(object, op);
+ }
+
+ /* need to issue a new write op after this */
+ clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags);
+ ret = 0;
+ } else if (flags & BIT(FSCACHE_OBJECT_IS_LOOKED_UP)) {
+ op->object = object;
+ object->n_ops++;
+ object->n_exclusive++; /* reads and writes must wait */
+ atomic_inc(&op->usage);
+ list_add_tail(&op->pend_link, &object->pending_ops);
+ fscache_stat(&fscache_n_op_pend);
+ ret = 0;
+ } else if (flags & BIT(FSCACHE_OBJECT_KILLED_BY_CACHE)) {
+ op->cancel(op);
+ op->state = FSCACHE_OP_ST_CANCELLED;
+ ret = -ENOBUFS;
+ } else {
+ fscache_report_unexpected_submission(object, op, ostate);
+ op->cancel(op);
+ op->state = FSCACHE_OP_ST_CANCELLED;
+ ret = -ENOBUFS;
+ }
+
+ spin_unlock(&object->lock);
+ return ret;
+}
+
/*
* submit an operation for an object
* - objects may be submitted only in the following states:
@@ -187,6 +234,7 @@ int fscache_submit_op(struct fscache_object *object,
struct fscache_operation *op)
{
const struct fscache_state *ostate;
+ unsigned long flags;
int ret;
_enter("{OBJ%x OP%x},{%u}",
@@ -204,7 +252,17 @@ int fscache_submit_op(struct fscache_object *object,
smp_rmb();
op->state = FSCACHE_OP_ST_PENDING;
- if (fscache_object_is_active(object)) {
+ flags = READ_ONCE(object->flags);
+ if (unlikely(!(flags & BIT(FSCACHE_OBJECT_IS_LIVE)))) {
+ fscache_stat(&fscache_n_op_rejected);
+ op->cancel(op);
+ op->state = FSCACHE_OP_ST_CANCELLED;
+ ret = -ENOBUFS;
+ } else if (unlikely(fscache_cache_is_broken(object))) {
+ op->cancel(op);
+ op->state = FSCACHE_OP_ST_CANCELLED;
+ ret = -EIO;
+ } else if (flags & BIT(FSCACHE_OBJECT_IS_AVAILABLE)) {
op->object = object;
object->n_ops++;
@@ -222,23 +280,21 @@ int fscache_submit_op(struct fscache_object *object,
fscache_run_op(object, op);
}
ret = 0;
- } else if (test_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)) {
+ } else if (flags & BIT(FSCACHE_OBJECT_IS_LOOKED_UP)) {
op->object = object;
object->n_ops++;
atomic_inc(&op->usage);
list_add_tail(&op->pend_link, &object->pending_ops);
fscache_stat(&fscache_n_op_pend);
ret = 0;
- } else if (fscache_object_is_dying(object)) {
- fscache_stat(&fscache_n_op_rejected);
- op->state = FSCACHE_OP_ST_CANCELLED;
- ret = -ENOBUFS;
- } else if (!test_bit(FSCACHE_IOERROR, &object->cache->flags)) {
- fscache_report_unexpected_submission(object, op, ostate);
- ASSERT(!fscache_object_is_active(object));
+ } else if (flags & BIT(FSCACHE_OBJECT_KILLED_BY_CACHE)) {
+ op->cancel(op);
op->state = FSCACHE_OP_ST_CANCELLED;
ret = -ENOBUFS;
} else {
+ fscache_report_unexpected_submission(object, op, ostate);
+ ASSERT(!fscache_object_is_active(object));
+ op->cancel(op);
op->state = FSCACHE_OP_ST_CANCELLED;
ret = -ENOBUFS;
}
@@ -293,9 +349,10 @@ void fscache_start_operations(struct fscache_object *object)
* cancel an operation that's pending on an object
*/
int fscache_cancel_op(struct fscache_operation *op,
- void (*do_cancel)(struct fscache_operation *))
+ bool cancel_in_progress_op)
{
struct fscache_object *object = op->object;
+ bool put = false;
int ret;
_enter("OBJ%x OP%x}", op->object->debug_id, op->debug_id);
@@ -309,19 +366,37 @@ int fscache_cancel_op(struct fscache_operation *op,
ret = -EBUSY;
if (op->state == FSCACHE_OP_ST_PENDING) {
ASSERT(!list_empty(&op->pend_link));
- fscache_stat(&fscache_n_op_cancelled);
list_del_init(&op->pend_link);
- if (do_cancel)
- do_cancel(op);
+ put = true;
+
+ fscache_stat(&fscache_n_op_cancelled);
+ op->cancel(op);
+ op->state = FSCACHE_OP_ST_CANCELLED;
+ if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
+ object->n_exclusive--;
+ if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
+ wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
+ ret = 0;
+ } else if (op->state == FSCACHE_OP_ST_IN_PROGRESS && cancel_in_progress_op) {
+ ASSERTCMP(object->n_in_progress, >, 0);
+ if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
+ object->n_exclusive--;
+ object->n_in_progress--;
+ if (object->n_in_progress == 0)
+ fscache_start_operations(object);
+
+ fscache_stat(&fscache_n_op_cancelled);
+ op->cancel(op);
op->state = FSCACHE_OP_ST_CANCELLED;
if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
object->n_exclusive--;
if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
- fscache_put_operation(op);
ret = 0;
}
+ if (put)
+ fscache_put_operation(op);
spin_unlock(&object->lock);
_leave(" = %d", ret);
return ret;
@@ -345,6 +420,7 @@ void fscache_cancel_all_ops(struct fscache_object *object)
list_del_init(&op->pend_link);
ASSERTCMP(op->state, ==, FSCACHE_OP_ST_PENDING);
+ op->cancel(op);
op->state = FSCACHE_OP_ST_CANCELLED;
if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
@@ -377,8 +453,12 @@ void fscache_op_complete(struct fscache_operation *op, bool cancelled)
spin_lock(&object->lock);
- op->state = cancelled ?
- FSCACHE_OP_ST_CANCELLED : FSCACHE_OP_ST_COMPLETE;
+ if (!cancelled) {
+ op->state = FSCACHE_OP_ST_COMPLETE;
+ } else {
+ op->cancel(op);
+ op->state = FSCACHE_OP_ST_CANCELLED;
+ }
if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
object->n_exclusive--;
@@ -409,9 +489,9 @@ void fscache_put_operation(struct fscache_operation *op)
return;
_debug("PUT OP");
- ASSERTIFCMP(op->state != FSCACHE_OP_ST_COMPLETE,
+ ASSERTIFCMP(op->state != FSCACHE_OP_ST_INITIALISED &&
+ op->state != FSCACHE_OP_ST_COMPLETE,
op->state, ==, FSCACHE_OP_ST_CANCELLED);
- op->state = FSCACHE_OP_ST_DEAD;
fscache_stat(&fscache_n_op_release);
@@ -419,37 +499,39 @@ void fscache_put_operation(struct fscache_operation *op)
op->release(op);
op->release = NULL;
}
+ op->state = FSCACHE_OP_ST_DEAD;
object = op->object;
+ if (likely(object)) {
+ if (test_bit(FSCACHE_OP_DEC_READ_CNT, &op->flags))
+ atomic_dec(&object->n_reads);
+ if (test_bit(FSCACHE_OP_UNUSE_COOKIE, &op->flags))
+ fscache_unuse_cookie(object);
- if (test_bit(FSCACHE_OP_DEC_READ_CNT, &op->flags))
- atomic_dec(&object->n_reads);
- if (test_bit(FSCACHE_OP_UNUSE_COOKIE, &op->flags))
- fscache_unuse_cookie(object);
+ /* now... we may get called with the object spinlock held, so we
+ * complete the cleanup here only if we can immediately acquire the
+ * lock, and defer it otherwise */
+ if (!spin_trylock(&object->lock)) {
+ _debug("defer put");
+ fscache_stat(&fscache_n_op_deferred_release);
- /* now... we may get called with the object spinlock held, so we
- * complete the cleanup here only if we can immediately acquire the
- * lock, and defer it otherwise */
- if (!spin_trylock(&object->lock)) {
- _debug("defer put");
- fscache_stat(&fscache_n_op_deferred_release);
+ cache = object->cache;
+ spin_lock(&cache->op_gc_list_lock);
+ list_add_tail(&op->pend_link, &cache->op_gc_list);
+ spin_unlock(&cache->op_gc_list_lock);
+ schedule_work(&cache->op_gc);
+ _leave(" [defer]");
+ return;
+ }
- cache = object->cache;
- spin_lock(&cache->op_gc_list_lock);
- list_add_tail(&op->pend_link, &cache->op_gc_list);
- spin_unlock(&cache->op_gc_list_lock);
- schedule_work(&cache->op_gc);
- _leave(" [defer]");
- return;
+ ASSERTCMP(object->n_ops, >, 0);
+ object->n_ops--;
+ if (object->n_ops == 0)
+ fscache_raise_event(object, FSCACHE_OBJECT_EV_CLEARED);
+
+ spin_unlock(&object->lock);
}
- ASSERTCMP(object->n_ops, >, 0);
- object->n_ops--;
- if (object->n_ops == 0)
- fscache_raise_event(object, FSCACHE_OBJECT_EV_CLEARED);
-
- spin_unlock(&object->lock);
-
kfree(op);
_leave(" [done]");
}
diff --git a/fs/fscache/page.c b/fs/fscache/page.c
index de33b3fccca6..483bbc613bf0 100644
--- a/fs/fscache/page.c
+++ b/fs/fscache/page.c
@@ -213,7 +213,7 @@ int __fscache_attr_changed(struct fscache_cookie *cookie)
return -ENOMEM;
}
- fscache_operation_init(op, fscache_attr_changed_op, NULL);
+ fscache_operation_init(op, fscache_attr_changed_op, NULL, NULL);
op->flags = FSCACHE_OP_ASYNC |
(1 << FSCACHE_OP_EXCLUSIVE) |
(1 << FSCACHE_OP_UNUSE_COOKIE);
@@ -239,7 +239,7 @@ nobufs_dec:
wake_cookie = __fscache_unuse_cookie(cookie);
nobufs:
spin_unlock(&cookie->lock);
- kfree(op);
+ fscache_put_operation(op);
if (wake_cookie)
__fscache_wake_unused_cookie(cookie);
fscache_stat(&fscache_n_attr_changed_nobufs);
@@ -248,6 +248,17 @@ nobufs:
}
EXPORT_SYMBOL(__fscache_attr_changed);
+/*
+ * Handle cancellation of a pending retrieval op
+ */
+static void fscache_do_cancel_retrieval(struct fscache_operation *_op)
+{
+ struct fscache_retrieval *op =
+ container_of(_op, struct fscache_retrieval, op);
+
+ atomic_set(&op->n_pages, 0);
+}
+
/*
* release a retrieval op reference
*/
@@ -258,11 +269,12 @@ static void fscache_release_retrieval_op(struct fscache_operation *_op)
_enter("{OP%x}", op->op.debug_id);
- ASSERTCMP(atomic_read(&op->n_pages), ==, 0);
+ ASSERTIFCMP(op->op.state != FSCACHE_OP_ST_INITIALISED,
+ atomic_read(&op->n_pages), ==, 0);
fscache_hist(fscache_retrieval_histogram, op->start_time);
if (op->context)
- fscache_put_context(op->op.object->cookie, op->context);
+ fscache_put_context(op->cookie, op->context);
_leave("");
}
@@ -285,15 +297,24 @@ static struct fscache_retrieval *fscache_alloc_retrieval(
return NULL;
}
- fscache_operation_init(&op->op, NULL, fscache_release_retrieval_op);
+ fscache_operation_init(&op->op, NULL,
+ fscache_do_cancel_retrieval,
+ fscache_release_retrieval_op);
op->op.flags = FSCACHE_OP_MYTHREAD |
(1UL << FSCACHE_OP_WAITING) |
(1UL << FSCACHE_OP_UNUSE_COOKIE);
+ op->cookie = cookie;
op->mapping = mapping;
op->end_io_func = end_io_func;
op->context = context;
op->start_time = jiffies;
INIT_LIST_HEAD(&op->to_do);
+
+ /* Pin the netfs read context in case we need to do the actual netfs
+ * read because we've encountered a cache read failure.
+ */
+ if (context)
+ fscache_get_context(op->cookie, context);
return op;
}
@@ -329,25 +350,13 @@ int fscache_wait_for_deferred_lookup(struct fscache_cookie *cookie)
return 0;
}
-/*
- * Handle cancellation of a pending retrieval op
- */
-static void fscache_do_cancel_retrieval(struct fscache_operation *_op)
-{
- struct fscache_retrieval *op =
- container_of(_op, struct fscache_retrieval, op);
-
- atomic_set(&op->n_pages, 0);
-}
-
/*
* wait for an object to become active (or dead)
*/
int fscache_wait_for_operation_activation(struct fscache_object *object,
struct fscache_operation *op,
atomic_t *stat_op_waits,
- atomic_t *stat_object_dead,
- void (*do_cancel)(struct fscache_operation *))
+ atomic_t *stat_object_dead)
{
int ret;
@@ -359,7 +368,7 @@ int fscache_wait_for_operation_activation(struct fscache_object *object,
fscache_stat(stat_op_waits);
if (wait_on_bit(&op->flags, FSCACHE_OP_WAITING,
TASK_INTERRUPTIBLE) != 0) {
- ret = fscache_cancel_op(op, do_cancel);
+ ret = fscache_cancel_op(op, false);
if (ret == 0)
return -ERESTARTSYS;
@@ -377,11 +386,13 @@ check_if_dead:
_leave(" = -ENOBUFS [cancelled]");
return -ENOBUFS;
}
- if (unlikely(fscache_object_is_dead(object))) {
- pr_err("%s() = -ENOBUFS [obj dead %d]\n", __func__, op->state);
- fscache_cancel_op(op, do_cancel);
+ if (unlikely(fscache_object_is_dying(object) ||
+ fscache_cache_is_broken(object))) {
+ enum fscache_operation_state state = op->state;
+ fscache_cancel_op(op, true);
if (stat_object_dead)
fscache_stat(stat_object_dead);
+ _leave(" = -ENOBUFS [obj dead %d]", state);
return -ENOBUFS;
}
return 0;
@@ -453,17 +464,12 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
fscache_stat(&fscache_n_retrieval_ops);
- /* pin the netfs read context in case we need to do the actual netfs
- * read because we've encountered a cache read failure */
- fscache_get_context(object->cookie, op->context);
-
/* we wait for the operation to become active, and then process it
* *here*, in this thread, and not in the thread pool */
ret = fscache_wait_for_operation_activation(
object, &op->op,
__fscache_stat(&fscache_n_retrieval_op_waits),
- __fscache_stat(&fscache_n_retrievals_object_dead),
- fscache_do_cancel_retrieval);
+ __fscache_stat(&fscache_n_retrievals_object_dead));
if (ret < 0)
goto error;
@@ -503,7 +509,7 @@ nobufs_unlock:
spin_unlock(&cookie->lock);
if (wake_cookie)
__fscache_wake_unused_cookie(cookie);
- kfree(op);
+ fscache_put_retrieval(op);
nobufs:
fscache_stat(&fscache_n_retrievals_nobufs);
_leave(" = -ENOBUFS");
@@ -584,17 +590,12 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
fscache_stat(&fscache_n_retrieval_ops);
- /* pin the netfs read context in case we need to do the actual netfs
- * read because we've encountered a cache read failure */
- fscache_get_context(object->cookie, op->context);
-
/* we wait for the operation to become active, and then process it
* *here*, in this thread, and not in the thread pool */
ret = fscache_wait_for_operation_activation(
object, &op->op,
__fscache_stat(&fscache_n_retrieval_op_waits),
- __fscache_stat(&fscache_n_retrievals_object_dead),
- fscache_do_cancel_retrieval);
+ __fscache_stat(&fscache_n_retrievals_object_dead));
if (ret < 0)
goto error;
@@ -632,7 +633,7 @@ nobufs_unlock_dec:
wake_cookie = __fscache_unuse_cookie(cookie);
nobufs_unlock:
spin_unlock(&cookie->lock);
- kfree(op);
+ fscache_put_retrieval(op);
if (wake_cookie)
__fscache_wake_unused_cookie(cookie);
nobufs:
@@ -700,8 +701,7 @@ int __fscache_alloc_page(struct fscache_cookie *cookie,
ret = fscache_wait_for_operation_activation(
object, &op->op,
__fscache_stat(&fscache_n_alloc_op_waits),
- __fscache_stat(&fscache_n_allocs_object_dead),
- fscache_do_cancel_retrieval);
+ __fscache_stat(&fscache_n_allocs_object_dead));
if (ret < 0)
goto error;
@@ -726,7 +726,7 @@ nobufs_unlock_dec:
wake_cookie = __fscache_unuse_cookie(cookie);
nobufs_unlock:
spin_unlock(&cookie->lock);
- kfree(op);
+ fscache_put_retrieval(op);
if (wake_cookie)
__fscache_wake_unused_cookie(cookie);
nobufs:
@@ -944,7 +944,7 @@ int __fscache_write_page(struct fscache_cookie *cookie,
if (!op)
goto nomem;
- fscache_operation_init(&op->op, fscache_write_op,
+ fscache_operation_init(&op->op, fscache_write_op, NULL,
fscache_release_write_op);
op->op.flags = FSCACHE_OP_ASYNC |
(1 << FSCACHE_OP_WAITING) |
@@ -1016,7 +1016,7 @@ already_pending:
spin_unlock(&object->lock);
spin_unlock(&cookie->lock);
radix_tree_preload_end();
- kfree(op);
+ fscache_put_operation(&op->op);
fscache_stat(&fscache_n_stores_ok);
_leave(" = 0");
return 0;
@@ -1036,7 +1036,7 @@ nobufs_unlock_obj:
nobufs:
spin_unlock(&cookie->lock);
radix_tree_preload_end();
- kfree(op);
+ fscache_put_operation(&op->op);
if (wake_cookie)
__fscache_wake_unused_cookie(cookie);
fscache_stat(&fscache_n_stores_nobufs);
@@ -1044,7 +1044,7 @@ nobufs:
return -ENOBUFS;
nomem_free:
- kfree(op);
+ fscache_put_operation(&op->op);
nomem:
fscache_stat(&fscache_n_stores_oom);
_leave(" = -ENOMEM");
diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c
index 40d13c70ef51..7cfa0aacdf6d 100644
--- a/fs/fscache/stats.c
+++ b/fs/fscache/stats.c
@@ -23,6 +23,7 @@ atomic_t fscache_n_op_run;
atomic_t fscache_n_op_enqueue;
atomic_t fscache_n_op_requeue;
atomic_t fscache_n_op_deferred_release;
+atomic_t fscache_n_op_initialised;
atomic_t fscache_n_op_release;
atomic_t fscache_n_op_gc;
atomic_t fscache_n_op_cancelled;
@@ -130,6 +131,11 @@ atomic_t fscache_n_cop_write_page;
atomic_t fscache_n_cop_uncache_page;
atomic_t fscache_n_cop_dissociate_pages;
+atomic_t fscache_n_cache_no_space_reject;
+atomic_t fscache_n_cache_stale_objects;
+atomic_t fscache_n_cache_retired_objects;
+atomic_t fscache_n_cache_culled_objects;
+
/*
* display the general statistics
*/
@@ -246,7 +252,8 @@ static int fscache_stats_show(struct seq_file *m, void *v)
atomic_read(&fscache_n_op_enqueue),
atomic_read(&fscache_n_op_cancelled),
atomic_read(&fscache_n_op_rejected));
- seq_printf(m, "Ops : dfr=%u rel=%u gc=%u\n",
+ seq_printf(m, "Ops : ini=%u dfr=%u rel=%u gc=%u\n",
+ atomic_read(&fscache_n_op_initialised),
atomic_read(&fscache_n_op_deferred_release),
atomic_read(&fscache_n_op_release),
atomic_read(&fscache_n_op_gc));
@@ -271,6 +278,11 @@ static int fscache_stats_show(struct seq_file *m, void *v)
atomic_read(&fscache_n_cop_write_page),
atomic_read(&fscache_n_cop_uncache_page),
atomic_read(&fscache_n_cop_dissociate_pages));
+ seq_printf(m, "CacheEv: nsp=%d stl=%d rtr=%d cul=%d\n",
+ atomic_read(&fscache_n_cache_no_space_reject),
+ atomic_read(&fscache_n_cache_stale_objects),
+ atomic_read(&fscache_n_cache_retired_objects),
+ atomic_read(&fscache_n_cache_culled_objects));
return 0;
}
diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h
index 771484993ca7..604e1526cd00 100644
--- a/include/linux/fscache-cache.h
+++ b/include/linux/fscache-cache.h
@@ -74,6 +74,7 @@ extern wait_queue_head_t fscache_cache_cleared_wq;
*/
typedef void (*fscache_operation_release_t)(struct fscache_operation *op);
typedef void (*fscache_operation_processor_t)(struct fscache_operation *op);
+typedef void (*fscache_operation_cancel_t)(struct fscache_operation *op);
enum fscache_operation_state {
FSCACHE_OP_ST_BLANK, /* Op is not yet submitted */
@@ -109,6 +110,9 @@ struct fscache_operation {
* the op in a non-pool thread */
fscache_operation_processor_t processor;
+ /* Operation cancellation cleanup (optional) */
+ fscache_operation_cancel_t cancel;
+
/* operation releaser */
fscache_operation_release_t release;
};
@@ -119,33 +123,17 @@ extern void fscache_op_work_func(struct work_struct *work);
extern void fscache_enqueue_operation(struct fscache_operation *);
extern void fscache_op_complete(struct fscache_operation *, bool);
extern void fscache_put_operation(struct fscache_operation *);
-
-/**
- * fscache_operation_init - Do basic initialisation of an operation
- * @op: The operation to initialise
- * @release: The release function to assign
- *
- * Do basic initialisation of an operation. The caller must still set flags,
- * object and processor if needed.
- */
-static inline void fscache_operation_init(struct fscache_operation *op,
- fscache_operation_processor_t processor,
- fscache_operation_release_t release)
-{
- INIT_WORK(&op->work, fscache_op_work_func);
- atomic_set(&op->usage, 1);
- op->state = FSCACHE_OP_ST_INITIALISED;
- op->debug_id = atomic_inc_return(&fscache_op_debug_id);
- op->processor = processor;
- op->release = release;
- INIT_LIST_HEAD(&op->pend_link);
-}
+extern void fscache_operation_init(struct fscache_operation *,
+ fscache_operation_processor_t,
+ fscache_operation_cancel_t,
+ fscache_operation_release_t);
/*
* data read operation
*/
struct fscache_retrieval {
struct fscache_operation op;
+ struct fscache_cookie *cookie; /* The netfs cookie */
struct address_space *mapping; /* netfs pages */
fscache_rw_complete_t end_io_func; /* function to call on I/O completion */
void *context; /* netfs read context (pinned) */
@@ -371,6 +359,7 @@ struct fscache_object {
#define FSCACHE_OBJECT_IS_LOOKED_UP 4 /* T if object has been looked up */
#define FSCACHE_OBJECT_IS_AVAILABLE 5 /* T if object has become active */
#define FSCACHE_OBJECT_RETIRED 6 /* T if object was retired on relinquishment */
+#define FSCACHE_OBJECT_KILLED_BY_CACHE 7 /* T if object was killed by the cache */
struct list_head cache_link; /* link in cache->object_list */
struct hlist_node cookie_link; /* link in cookie->backing_objects */
@@ -410,17 +399,16 @@ static inline bool fscache_object_is_available(struct fscache_object *object)
return test_bit(FSCACHE_OBJECT_IS_AVAILABLE, &object->flags);
}
+static inline bool fscache_cache_is_broken(struct fscache_object *object)
+{
+ return test_bit(FSCACHE_IOERROR, &object->cache->flags);
+}
+
static inline bool fscache_object_is_active(struct fscache_object *object)
{
return fscache_object_is_available(object) &&
fscache_object_is_live(object) &&
- !test_bit(FSCACHE_IOERROR, &object->cache->flags);
-}
-
-static inline bool fscache_object_is_dead(struct fscache_object *object)
-{
- return fscache_object_is_dying(object) &&
- test_bit(FSCACHE_IOERROR, &object->cache->flags);
+ !fscache_cache_is_broken(object);
}
/**
@@ -551,4 +539,15 @@ extern enum fscache_checkaux fscache_check_aux(struct fscache_object *object,
const void *data,
uint16_t datalen);
+extern void fscache_object_retrying_stale(struct fscache_object *object);
+
+enum fscache_why_object_killed {
+ FSCACHE_OBJECT_IS_STALE,
+ FSCACHE_OBJECT_NO_SPACE,
+ FSCACHE_OBJECT_WAS_RETIRED,
+ FSCACHE_OBJECT_WAS_CULLED,
+};
+extern void fscache_object_mark_killed(struct fscache_object *object,
+ enum fscache_why_object_killed why);
+
#endif /* _LINUX_FSCACHE_CACHE_H */