diff options
Diffstat (limited to 'fs/fscache')
| -rw-r--r-- | fs/fscache/cookie.c | 60 | ||||
| -rw-r--r-- | fs/fscache/internal.h | 10 | ||||
| -rw-r--r-- | fs/fscache/object.c | 72 | ||||
| -rw-r--r-- | fs/fscache/operation.c | 32 | ||||
| -rw-r--r-- | fs/fscache/page.c | 51 | ||||
| -rw-r--r-- | fs/fscache/stats.c | 11 |
6 files changed, 235 insertions, 1 deletions
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c index 66be9eccede..8dcb114758e 100644 --- a/fs/fscache/cookie.c +++ b/fs/fscache/cookie.c @@ -370,6 +370,66 @@ cant_attach_object: } /* + * Invalidate an object. Callable with spinlocks held. + */ +void __fscache_invalidate(struct fscache_cookie *cookie) +{ + struct fscache_object *object; + + _enter("{%s}", cookie->def->name); + + fscache_stat(&fscache_n_invalidates); + + /* Only permit invalidation of data files. Invalidating an index will + * require the caller to release all its attachments to the tree rooted + * there, and if it's doing that, it may as well just retire the + * cookie. + */ + ASSERTCMP(cookie->def->type, ==, FSCACHE_COOKIE_TYPE_DATAFILE); + + /* We will be updating the cookie too. */ + BUG_ON(!cookie->def->get_aux); + + /* If there's an object, we tell the object state machine to handle the + * invalidation on our behalf, otherwise there's nothing to do. + */ + if (!hlist_empty(&cookie->backing_objects)) { + spin_lock(&cookie->lock); + + if (!hlist_empty(&cookie->backing_objects) && + !test_and_set_bit(FSCACHE_COOKIE_INVALIDATING, + &cookie->flags)) { + object = hlist_entry(cookie->backing_objects.first, + struct fscache_object, + cookie_link); + if (object->state < FSCACHE_OBJECT_DYING) + fscache_raise_event( + object, FSCACHE_OBJECT_EV_INVALIDATE); + } + + spin_unlock(&cookie->lock); + } + + _leave(""); +} +EXPORT_SYMBOL(__fscache_invalidate); + +/* + * Wait for object invalidation to complete. + */ +void __fscache_wait_on_invalidate(struct fscache_cookie *cookie) +{ + _enter("%p", cookie); + + wait_on_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING, + fscache_wait_bit_interruptible, + TASK_UNINTERRUPTIBLE); + + _leave(""); +} +EXPORT_SYMBOL(__fscache_wait_on_invalidate); + +/* * update the index entries backing a cookie */ void __fscache_update_cookie(struct fscache_cookie *cookie) diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h index f6aad48d38a..c8117930393 100644 --- a/fs/fscache/internal.h +++ b/fs/fscache/internal.h @@ -122,11 +122,17 @@ extern int fscache_submit_exclusive_op(struct fscache_object *, extern int fscache_submit_op(struct fscache_object *, struct fscache_operation *); extern int fscache_cancel_op(struct fscache_operation *); +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 *); extern void fscache_operation_gc(struct work_struct *); /* + * page.c + */ +extern void fscache_invalidate_writes(struct fscache_cookie *); + +/* * proc.c */ #ifdef CONFIG_PROC_FS @@ -205,6 +211,9 @@ extern atomic_t fscache_n_acquires_ok; extern atomic_t fscache_n_acquires_nobufs; extern atomic_t fscache_n_acquires_oom; +extern atomic_t fscache_n_invalidates; +extern atomic_t fscache_n_invalidates_run; + extern atomic_t fscache_n_updates; extern atomic_t fscache_n_updates_null; extern atomic_t fscache_n_updates_run; @@ -237,6 +246,7 @@ extern atomic_t fscache_n_cop_alloc_object; extern atomic_t fscache_n_cop_lookup_object; extern atomic_t fscache_n_cop_lookup_complete; extern atomic_t fscache_n_cop_grab_object; +extern atomic_t fscache_n_cop_invalidate_object; extern atomic_t fscache_n_cop_update_object; extern atomic_t fscache_n_cop_drop_object; extern atomic_t fscache_n_cop_put_object; diff --git a/fs/fscache/object.c b/fs/fscache/object.c index 773bc798a41..80b549141ea 100644 --- a/fs/fscache/object.c +++ b/fs/fscache/object.c @@ -14,6 +14,7 @@ #define FSCACHE_DEBUG_LEVEL COOKIE #include <linux/module.h> +#include <linux/slab.h> #include "internal.h" const char *fscache_object_states[FSCACHE_OBJECT__NSTATES] = { @@ -22,6 +23,7 @@ const char *fscache_object_states[FSCACHE_OBJECT__NSTATES] = { [FSCACHE_OBJECT_CREATING] = "OBJECT_CREATING", [FSCACHE_OBJECT_AVAILABLE] = "OBJECT_AVAILABLE", [FSCACHE_OBJECT_ACTIVE] = "OBJECT_ACTIVE", + [FSCACHE_OBJECT_INVALIDATING] = "OBJECT_INVALIDATING", [FSCACHE_OBJECT_UPDATING] = "OBJECT_UPDATING", [FSCACHE_OBJECT_DYING] = "OBJECT_DYING", [FSCACHE_OBJECT_LC_DYING] = "OBJECT_LC_DYING", @@ -39,6 +41,7 @@ const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5] = { [FSCACHE_OBJECT_CREATING] = "CRTN", [FSCACHE_OBJECT_AVAILABLE] = "AVBL", [FSCACHE_OBJECT_ACTIVE] = "ACTV", + [FSCACHE_OBJECT_INVALIDATING] = "INVL", [FSCACHE_OBJECT_UPDATING] = "UPDT", [FSCACHE_OBJECT_DYING] = "DYNG", [FSCACHE_OBJECT_LC_DYING] = "LCDY", @@ -54,6 +57,7 @@ static void fscache_put_object(struct fscache_object *); static void fscache_initialise_object(struct fscache_object *); static void fscache_lookup_object(struct fscache_object *); static void fscache_object_available(struct fscache_object *); +static void fscache_invalidate_object(struct fscache_object *); static void fscache_release_object(struct fscache_object *); static void fscache_withdraw_object(struct fscache_object *); static void fscache_enqueue_dependents(struct fscache_object *); @@ -79,6 +83,15 @@ static inline void fscache_done_parent_op(struct fscache_object *object) } /* + * Notify netfs of invalidation completion. + */ +static inline void fscache_invalidation_complete(struct fscache_cookie *cookie) +{ + if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) + wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING); +} + +/* * process events that have been sent to an object's state machine * - initiates parent lookup * - does object lookup @@ -125,6 +138,16 @@ static void fscache_object_state_machine(struct fscache_object *object) case FSCACHE_OBJECT_ACTIVE: goto active_transit; + /* Invalidate an object on disk */ + case FSCACHE_OBJECT_INVALIDATING: + clear_bit(FSCACHE_OBJECT_EV_INVALIDATE, &object->events); + fscache_stat(&fscache_n_invalidates_run); + fscache_stat(&fscache_n_cop_invalidate_object); + fscache_invalidate_object(object); + fscache_stat_d(&fscache_n_cop_invalidate_object); + fscache_raise_event(object, FSCACHE_OBJECT_EV_UPDATE); + goto active_transit; + /* update the object metadata on disk */ case FSCACHE_OBJECT_UPDATING: clear_bit(FSCACHE_OBJECT_EV_UPDATE, &object->events); @@ -275,6 +298,9 @@ active_transit: case FSCACHE_OBJECT_EV_ERROR: new_state = FSCACHE_OBJECT_DYING; goto change_state; + case FSCACHE_OBJECT_EV_INVALIDATE: + new_state = FSCACHE_OBJECT_INVALIDATING; + goto change_state; case FSCACHE_OBJECT_EV_UPDATE: new_state = FSCACHE_OBJECT_UPDATING; goto change_state; @@ -679,6 +705,7 @@ static void fscache_withdraw_object(struct fscache_object *object) if (object->cookie == cookie) { hlist_del_init(&object->cookie_link); object->cookie = NULL; + fscache_invalidation_complete(cookie); detached = true; } spin_unlock(&cookie->lock); @@ -888,3 +915,48 @@ enum fscache_checkaux fscache_check_aux(struct fscache_object *object, return result; } EXPORT_SYMBOL(fscache_check_aux); + +/* + * Asynchronously invalidate an object. + */ +static void fscache_invalidate_object(struct fscache_object *object) +{ + struct fscache_operation *op; + struct fscache_cookie *cookie = object->cookie; + + _enter("{OBJ%x}", object->debug_id); + + /* Reject any new read/write ops and abort any that are pending. */ + fscache_invalidate_writes(cookie); + clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags); + fscache_cancel_all_ops(object); + + /* Now we have to wait for in-progress reads and writes */ + op = kzalloc(sizeof(*op), GFP_KERNEL); + if (!op) { + fscache_raise_event(object, FSCACHE_OBJECT_EV_ERROR); + _leave(" [ENOMEM]"); + return; + } + + fscache_operation_init(op, object->cache->ops->invalidate_object, NULL); + op->flags = FSCACHE_OP_ASYNC | (1 << FSCACHE_OP_EXCLUSIVE); + + spin_lock(&cookie->lock); + if (fscache_submit_exclusive_op(object, op) < 0) + BUG(); + spin_unlock(&cookie->lock); + fscache_put_operation(op); + + /* Once we've completed the invalidation, we know there will be no data + * stored in the cache and thus we can reinstate the data-check-skip + * optimisation. + */ + set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags); + + /* We can allow read and write requests to come in once again. They'll + * queue up behind our exclusive invalidation operation. + */ + fscache_invalidation_complete(cookie); + _leave(""); +} diff --git a/fs/fscache/operation.c b/fs/fscache/operation.c index 748f9553c2c..c58dbe61326 100644 --- a/fs/fscache/operation.c +++ b/fs/fscache/operation.c @@ -324,6 +324,38 @@ int fscache_cancel_op(struct fscache_operation *op) } /* + * Cancel all pending operations on an object + */ +void fscache_cancel_all_ops(struct fscache_object *object) +{ + struct fscache_operation *op; + + _enter("OBJ%x", object->debug_id); + + spin_lock(&object->lock); + + while (!list_empty(&object->pending_ops)) { + op = list_entry(object->pending_ops.next, + struct fscache_operation, pend_link); + fscache_stat(&fscache_n_op_cancelled); + list_del_init(&op->pend_link); + + ASSERTCMP(op->state, ==, FSCACHE_OP_ST_PENDING); + 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); + cond_resched_lock(&object->lock); + } + + spin_unlock(&object->lock); + _leave(""); +} + +/* * Record the completion of an in-progress operation. */ void fscache_op_complete(struct fscache_operation *op) diff --git a/fs/fscache/page.c b/fs/fscache/page.c index b38b13d2a55..7bf9d255705 100644 --- a/fs/fscache/page.c +++ b/fs/fscache/page.c @@ -361,6 +361,11 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie, if (hlist_empty(&cookie->backing_objects)) goto nobufs; + if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { + _leave(" = -ENOBUFS [invalidating]"); + return -ENOBUFS; + } + ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); ASSERTCMP(page, !=, NULL); @@ -483,6 +488,11 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie, if (hlist_empty(&cookie->backing_objects)) goto nobufs; + if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { + _leave(" = -ENOBUFS [invalidating]"); + return -ENOBUFS; + } + ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); ASSERTCMP(*nr_pages, >, 0); ASSERT(!list_empty(pages)); @@ -591,6 +601,11 @@ int __fscache_alloc_page(struct fscache_cookie *cookie, ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); ASSERTCMP(page, !=, NULL); + if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { + _leave(" = -ENOBUFS [invalidating]"); + return -ENOBUFS; + } + if (fscache_wait_for_deferred_lookup(cookie) < 0) return -ERESTARTSYS; @@ -731,6 +746,37 @@ superseded: } /* + * Clear the pages pending writing for invalidation + */ +void fscache_invalidate_writes(struct fscache_cookie *cookie) +{ + struct page *page; + void *results[16]; + int n, i; + + _enter(""); + + while (spin_lock(&cookie->stores_lock), + n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0, + ARRAY_SIZE(results), + FSCACHE_COOKIE_PENDING_TAG), + n > 0) { + for (i = n - 1; i >= 0; i--) { + page = results[i]; + radix_tree_delete(&cookie->stores, page->index); + } + + spin_unlock(&cookie->stores_lock); + + for (i = n - 1; i >= 0; i--) + page_cache_release(results[i]); + } + + spin_unlock(&cookie->stores_lock); + _leave(""); +} + +/* * request a page be stored in the cache * - returns: * -ENOMEM - out of memory, nothing done @@ -776,6 +822,11 @@ int __fscache_write_page(struct fscache_cookie *cookie, fscache_stat(&fscache_n_stores); + if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { + _leave(" = -ENOBUFS [invalidating]"); + return -ENOBUFS; + } + op = kzalloc(sizeof(*op), GFP_NOIO | __GFP_NOMEMALLOC | __GFP_NORETRY); if (!op) goto nomem; diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c index 4765190d537..51cdaee1410 100644 --- a/fs/fscache/stats.c +++ b/fs/fscache/stats.c @@ -80,6 +80,9 @@ atomic_t fscache_n_acquires_ok; atomic_t fscache_n_acquires_nobufs; atomic_t fscache_n_acquires_oom; +atomic_t fscache_n_invalidates; +atomic_t fscache_n_invalidates_run; + atomic_t fscache_n_updates; atomic_t fscache_n_updates_null; atomic_t fscache_n_updates_run; @@ -112,6 +115,7 @@ atomic_t fscache_n_cop_alloc_object; atomic_t fscache_n_cop_lookup_object; atomic_t fscache_n_cop_lookup_complete; atomic_t fscache_n_cop_grab_object; +atomic_t fscache_n_cop_invalidate_object; atomic_t fscache_n_cop_update_object; atomic_t fscache_n_cop_drop_object; atomic_t fscache_n_cop_put_object; @@ -168,6 +172,10 @@ static int fscache_stats_show(struct seq_file *m, void *v) atomic_read(&fscache_n_object_created), atomic_read(&fscache_n_object_lookups_timed_out)); + seq_printf(m, "Invals : n=%u run=%u\n", + atomic_read(&fscache_n_invalidates), + atomic_read(&fscache_n_invalidates_run)); + seq_printf(m, "Updates: n=%u nul=%u run=%u\n", atomic_read(&fscache_n_updates), atomic_read(&fscache_n_updates_null), @@ -246,7 +254,8 @@ static int fscache_stats_show(struct seq_file *m, void *v) atomic_read(&fscache_n_cop_lookup_object), atomic_read(&fscache_n_cop_lookup_complete), atomic_read(&fscache_n_cop_grab_object)); - seq_printf(m, "CacheOp: upo=%d dro=%d pto=%d atc=%d syn=%d\n", + seq_printf(m, "CacheOp: inv=%d upo=%d dro=%d pto=%d atc=%d syn=%d\n", + atomic_read(&fscache_n_cop_invalidate_object), atomic_read(&fscache_n_cop_update_object), atomic_read(&fscache_n_cop_drop_object), atomic_read(&fscache_n_cop_put_object), |