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-rw-r--r--fs/fscache/cookie.c186
-rw-r--r--fs/fscache/fsdef.c1
-rw-r--r--fs/fscache/netfs.c1
-rw-r--r--fs/fscache/object.c7
-rw-r--r--fs/fscache/page.c17
5 files changed, 155 insertions, 57 deletions
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c
index d851aa555d2..29d7feb62cf 100644
--- a/fs/fscache/cookie.c
+++ b/fs/fscache/cookie.c
@@ -58,15 +58,16 @@ void fscache_cookie_init_once(void *_cookie)
struct fscache_cookie *__fscache_acquire_cookie(
struct fscache_cookie *parent,
const struct fscache_cookie_def *def,
- void *netfs_data)
+ void *netfs_data,
+ bool enable)
{
struct fscache_cookie *cookie;
BUG_ON(!def);
- _enter("{%s},{%s},%p",
+ _enter("{%s},{%s},%p,%u",
parent ? (char *) parent->def->name : "<no-parent>",
- def->name, netfs_data);
+ def->name, netfs_data, enable);
fscache_stat(&fscache_n_acquires);
@@ -106,7 +107,7 @@ struct fscache_cookie *__fscache_acquire_cookie(
cookie->def = def;
cookie->parent = parent;
cookie->netfs_data = netfs_data;
- cookie->flags = 0;
+ cookie->flags = (1 << FSCACHE_COOKIE_NO_DATA_YET);
/* radix tree insertion won't use the preallocation pool unless it's
* told it may not wait */
@@ -124,16 +125,22 @@ struct fscache_cookie *__fscache_acquire_cookie(
break;
}
- /* if the object is an index then we need do nothing more here - we
- * create indices on disk when we need them as an index may exist in
- * multiple caches */
- if (cookie->def->type != FSCACHE_COOKIE_TYPE_INDEX) {
- if (fscache_acquire_non_index_cookie(cookie) < 0) {
- atomic_dec(&parent->n_children);
- __fscache_cookie_put(cookie);
- fscache_stat(&fscache_n_acquires_nobufs);
- _leave(" = NULL");
- return NULL;
+ if (enable) {
+ /* if the object is an index then we need do nothing more here
+ * - we create indices on disk when we need them as an index
+ * may exist in multiple caches */
+ if (cookie->def->type != FSCACHE_COOKIE_TYPE_INDEX) {
+ if (fscache_acquire_non_index_cookie(cookie) == 0) {
+ set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
+ } else {
+ atomic_dec(&parent->n_children);
+ __fscache_cookie_put(cookie);
+ fscache_stat(&fscache_n_acquires_nobufs);
+ _leave(" = NULL");
+ return NULL;
+ }
+ } else {
+ set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
}
}
@@ -144,6 +151,39 @@ struct fscache_cookie *__fscache_acquire_cookie(
EXPORT_SYMBOL(__fscache_acquire_cookie);
/*
+ * Enable a cookie to permit it to accept new operations.
+ */
+void __fscache_enable_cookie(struct fscache_cookie *cookie,
+ bool (*can_enable)(void *data),
+ void *data)
+{
+ _enter("%p", cookie);
+
+ wait_on_bit_lock(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK,
+ fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+
+ if (test_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags))
+ goto out_unlock;
+
+ if (can_enable && !can_enable(data)) {
+ /* The netfs decided it didn't want to enable after all */
+ } else if (cookie->def->type != FSCACHE_COOKIE_TYPE_INDEX) {
+ /* Wait for outstanding disablement to complete */
+ __fscache_wait_on_invalidate(cookie);
+
+ if (fscache_acquire_non_index_cookie(cookie) == 0)
+ set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
+ } else {
+ set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
+ }
+
+out_unlock:
+ clear_bit_unlock(FSCACHE_COOKIE_ENABLEMENT_LOCK, &cookie->flags);
+ wake_up_bit(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK);
+}
+EXPORT_SYMBOL(__fscache_enable_cookie);
+
+/*
* acquire a non-index cookie
* - this must make sure the index chain is instantiated and instantiate the
* object representation too
@@ -157,7 +197,7 @@ static int fscache_acquire_non_index_cookie(struct fscache_cookie *cookie)
_enter("");
- cookie->flags = 1 << FSCACHE_COOKIE_UNAVAILABLE;
+ set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
/* now we need to see whether the backing objects for this cookie yet
* exist, if not there'll be nothing to search */
@@ -180,9 +220,7 @@ static int fscache_acquire_non_index_cookie(struct fscache_cookie *cookie)
_debug("cache %s", cache->tag->name);
- cookie->flags =
- (1 << FSCACHE_COOKIE_LOOKING_UP) |
- (1 << FSCACHE_COOKIE_NO_DATA_YET);
+ set_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
/* ask the cache to allocate objects for this cookie and its parent
* chain */
@@ -398,7 +436,8 @@ void __fscache_invalidate(struct fscache_cookie *cookie)
if (!hlist_empty(&cookie->backing_objects)) {
spin_lock(&cookie->lock);
- if (!hlist_empty(&cookie->backing_objects) &&
+ if (fscache_cookie_enabled(cookie) &&
+ !hlist_empty(&cookie->backing_objects) &&
!test_and_set_bit(FSCACHE_COOKIE_INVALIDATING,
&cookie->flags)) {
object = hlist_entry(cookie->backing_objects.first,
@@ -452,10 +491,14 @@ void __fscache_update_cookie(struct fscache_cookie *cookie)
spin_lock(&cookie->lock);
- /* update the index entry on disk in each cache backing this cookie */
- hlist_for_each_entry(object,
- &cookie->backing_objects, cookie_link) {
- fscache_raise_event(object, FSCACHE_OBJECT_EV_UPDATE);
+ if (fscache_cookie_enabled(cookie)) {
+ /* update the index entry on disk in each cache backing this
+ * cookie.
+ */
+ hlist_for_each_entry(object,
+ &cookie->backing_objects, cookie_link) {
+ fscache_raise_event(object, FSCACHE_OBJECT_EV_UPDATE);
+ }
}
spin_unlock(&cookie->lock);
@@ -464,28 +507,14 @@ void __fscache_update_cookie(struct fscache_cookie *cookie)
EXPORT_SYMBOL(__fscache_update_cookie);
/*
- * release a cookie back to the cache
- * - the object will be marked as recyclable on disk if retire is true
- * - all dependents of this cookie must have already been unregistered
- * (indices/files/pages)
+ * Disable a cookie to stop it from accepting new requests from the netfs.
*/
-void __fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire)
+void __fscache_disable_cookie(struct fscache_cookie *cookie, bool invalidate)
{
struct fscache_object *object;
+ bool awaken = false;
- fscache_stat(&fscache_n_relinquishes);
- if (retire)
- fscache_stat(&fscache_n_relinquishes_retire);
-
- if (!cookie) {
- fscache_stat(&fscache_n_relinquishes_null);
- _leave(" [no cookie]");
- return;
- }
-
- _enter("%p{%s,%p,%d},%d",
- cookie, cookie->def->name, cookie->netfs_data,
- atomic_read(&cookie->n_active), retire);
+ _enter("%p,%u", cookie, invalidate);
ASSERTCMP(atomic_read(&cookie->n_active), >, 0);
@@ -495,24 +524,82 @@ void __fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire)
BUG();
}
- /* No further netfs-accessing operations on this cookie permitted */
- set_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags);
- if (retire)
- set_bit(FSCACHE_COOKIE_RETIRED, &cookie->flags);
+ wait_on_bit_lock(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK,
+ fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+ if (!test_and_clear_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags))
+ goto out_unlock_enable;
+
+ /* If the cookie is being invalidated, wait for that to complete first
+ * so that we can reuse the flag.
+ */
+ __fscache_wait_on_invalidate(cookie);
+
+ /* Dispose of the backing objects */
+ set_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags);
spin_lock(&cookie->lock);
- hlist_for_each_entry(object, &cookie->backing_objects, cookie_link) {
- fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
+ if (!hlist_empty(&cookie->backing_objects)) {
+ hlist_for_each_entry(object, &cookie->backing_objects, cookie_link) {
+ if (invalidate)
+ set_bit(FSCACHE_OBJECT_RETIRED, &object->flags);
+ fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
+ }
+ } else {
+ if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
+ awaken = true;
}
spin_unlock(&cookie->lock);
+ if (awaken)
+ wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING);
/* Wait for cessation of activity requiring access to the netfs (when
- * n_active reaches 0).
+ * n_active reaches 0). This makes sure outstanding reads and writes
+ * have completed.
*/
if (!atomic_dec_and_test(&cookie->n_active))
wait_on_atomic_t(&cookie->n_active, fscache_wait_atomic_t,
TASK_UNINTERRUPTIBLE);
+ /* Reset the cookie state if it wasn't relinquished */
+ if (!test_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags)) {
+ atomic_inc(&cookie->n_active);
+ set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
+ }
+
+out_unlock_enable:
+ clear_bit_unlock(FSCACHE_COOKIE_ENABLEMENT_LOCK, &cookie->flags);
+ wake_up_bit(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK);
+ _leave("");
+}
+EXPORT_SYMBOL(__fscache_disable_cookie);
+
+/*
+ * release a cookie back to the cache
+ * - the object will be marked as recyclable on disk if retire is true
+ * - all dependents of this cookie must have already been unregistered
+ * (indices/files/pages)
+ */
+void __fscache_relinquish_cookie(struct fscache_cookie *cookie, bool retire)
+{
+ fscache_stat(&fscache_n_relinquishes);
+ if (retire)
+ fscache_stat(&fscache_n_relinquishes_retire);
+
+ if (!cookie) {
+ fscache_stat(&fscache_n_relinquishes_null);
+ _leave(" [no cookie]");
+ return;
+ }
+
+ _enter("%p{%s,%p,%d},%d",
+ cookie, cookie->def->name, cookie->netfs_data,
+ atomic_read(&cookie->n_active), retire);
+
+ /* No further netfs-accessing operations on this cookie permitted */
+ set_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags);
+
+ __fscache_disable_cookie(cookie, retire);
+
/* Clear pointers back to the netfs */
cookie->netfs_data = NULL;
cookie->def = NULL;
@@ -592,7 +679,8 @@ int __fscache_check_consistency(struct fscache_cookie *cookie)
spin_lock(&cookie->lock);
- if (hlist_empty(&cookie->backing_objects))
+ if (!fscache_cookie_enabled(cookie) ||
+ hlist_empty(&cookie->backing_objects))
goto inconsistent;
object = hlist_entry(cookie->backing_objects.first,
struct fscache_object, cookie_link);
diff --git a/fs/fscache/fsdef.c b/fs/fscache/fsdef.c
index 10a2ade0bdf..5a117df2a9e 100644
--- a/fs/fscache/fsdef.c
+++ b/fs/fscache/fsdef.c
@@ -59,6 +59,7 @@ struct fscache_cookie fscache_fsdef_index = {
.lock = __SPIN_LOCK_UNLOCKED(fscache_fsdef_index.lock),
.backing_objects = HLIST_HEAD_INIT,
.def = &fscache_fsdef_index_def,
+ .flags = 1 << FSCACHE_COOKIE_ENABLED,
};
EXPORT_SYMBOL(fscache_fsdef_index);
diff --git a/fs/fscache/netfs.c b/fs/fscache/netfs.c
index b1bb6117473..989f3940154 100644
--- a/fs/fscache/netfs.c
+++ b/fs/fscache/netfs.c
@@ -45,6 +45,7 @@ int __fscache_register_netfs(struct fscache_netfs *netfs)
netfs->primary_index->def = &fscache_fsdef_netfs_def;
netfs->primary_index->parent = &fscache_fsdef_index;
netfs->primary_index->netfs_data = netfs;
+ netfs->primary_index->flags = 1 << FSCACHE_COOKIE_ENABLED;
atomic_inc(&netfs->primary_index->parent->usage);
atomic_inc(&netfs->primary_index->parent->n_children);
diff --git a/fs/fscache/object.c b/fs/fscache/object.c
index 86d75a60b20..dcb82161777 100644
--- a/fs/fscache/object.c
+++ b/fs/fscache/object.c
@@ -495,6 +495,7 @@ void fscache_object_lookup_negative(struct fscache_object *object)
* returning ENODATA.
*/
set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
+ clear_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
_debug("wake up lookup %p", &cookie->flags);
clear_bit_unlock(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
@@ -527,6 +528,7 @@ void fscache_obtained_object(struct fscache_object *object)
/* We do (presumably) have data */
clear_bit_unlock(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
+ clear_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
/* Allow write requests to begin stacking up and read requests
* to begin shovelling data.
@@ -679,7 +681,8 @@ static const struct fscache_state *fscache_drop_object(struct fscache_object *ob
*/
spin_lock(&cookie->lock);
hlist_del_init(&object->cookie_link);
- if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
+ if (hlist_empty(&cookie->backing_objects) &&
+ test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
awaken = true;
spin_unlock(&cookie->lock);
@@ -927,7 +930,7 @@ static const struct fscache_state *_fscache_invalidate_object(struct fscache_obj
*/
if (!fscache_use_cookie(object)) {
ASSERT(object->cookie->stores.rnode == NULL);
- set_bit(FSCACHE_COOKIE_RETIRED, &cookie->flags);
+ set_bit(FSCACHE_OBJECT_RETIRED, &object->flags);
_leave(" [no cookie]");
return transit_to(KILL_OBJECT);
}
diff --git a/fs/fscache/page.c b/fs/fscache/page.c
index 0fe42a6d0e9..7f5c658af75 100644
--- a/fs/fscache/page.c
+++ b/fs/fscache/page.c
@@ -204,7 +204,8 @@ int __fscache_attr_changed(struct fscache_cookie *cookie)
spin_lock(&cookie->lock);
- if (hlist_empty(&cookie->backing_objects))
+ if (!fscache_cookie_enabled(cookie) ||
+ hlist_empty(&cookie->backing_objects))
goto nobufs;
object = hlist_entry(cookie->backing_objects.first,
struct fscache_object, cookie_link);
@@ -410,7 +411,7 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
return -ERESTARTSYS;
op = fscache_alloc_retrieval(cookie, page->mapping,
- end_io_func,context);
+ end_io_func, context);
if (!op) {
_leave(" = -ENOMEM");
return -ENOMEM;
@@ -419,7 +420,8 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
spin_lock(&cookie->lock);
- if (hlist_empty(&cookie->backing_objects))
+ if (!fscache_cookie_enabled(cookie) ||
+ hlist_empty(&cookie->backing_objects))
goto nobufs_unlock;
object = hlist_entry(cookie->backing_objects.first,
struct fscache_object, cookie_link);
@@ -551,7 +553,8 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
spin_lock(&cookie->lock);
- if (hlist_empty(&cookie->backing_objects))
+ if (!fscache_cookie_enabled(cookie) ||
+ hlist_empty(&cookie->backing_objects))
goto nobufs_unlock;
object = hlist_entry(cookie->backing_objects.first,
struct fscache_object, cookie_link);
@@ -666,7 +669,8 @@ int __fscache_alloc_page(struct fscache_cookie *cookie,
spin_lock(&cookie->lock);
- if (hlist_empty(&cookie->backing_objects))
+ if (!fscache_cookie_enabled(cookie) ||
+ hlist_empty(&cookie->backing_objects))
goto nobufs_unlock;
object = hlist_entry(cookie->backing_objects.first,
struct fscache_object, cookie_link);
@@ -938,7 +942,8 @@ int __fscache_write_page(struct fscache_cookie *cookie,
ret = -ENOBUFS;
spin_lock(&cookie->lock);
- if (hlist_empty(&cookie->backing_objects))
+ if (!fscache_cookie_enabled(cookie) ||
+ hlist_empty(&cookie->backing_objects))
goto nobufs;
object = hlist_entry(cookie->backing_objects.first,
struct fscache_object, cookie_link);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-20 17:36:52 +0000