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Diffstat (limited to 'fs/nfsd/filecache.c')
-rw-r--r--fs/nfsd/filecache.c313
1 files changed, 237 insertions, 76 deletions
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index 32a9bf22ac08..22e77ede9f14 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -27,7 +27,6 @@
#define NFSD_FILE_HASH_SIZE (1 << NFSD_FILE_HASH_BITS)
#define NFSD_LAUNDRETTE_DELAY (2 * HZ)
-#define NFSD_FILE_LRU_RESCAN (0)
#define NFSD_FILE_SHUTDOWN (1)
#define NFSD_FILE_LRU_THRESHOLD (4096UL)
#define NFSD_FILE_LRU_LIMIT (NFSD_FILE_LRU_THRESHOLD << 2)
@@ -44,6 +43,17 @@ struct nfsd_fcache_bucket {
static DEFINE_PER_CPU(unsigned long, nfsd_file_cache_hits);
+struct nfsd_fcache_disposal {
+ struct list_head list;
+ struct work_struct work;
+ struct net *net;
+ spinlock_t lock;
+ struct list_head freeme;
+ struct rcu_head rcu;
+};
+
+static struct workqueue_struct *nfsd_filecache_wq __read_mostly;
+
static struct kmem_cache *nfsd_file_slab;
static struct kmem_cache *nfsd_file_mark_slab;
static struct nfsd_fcache_bucket *nfsd_file_hashtbl;
@@ -52,32 +62,21 @@ static long nfsd_file_lru_flags;
static struct fsnotify_group *nfsd_file_fsnotify_group;
static atomic_long_t nfsd_filecache_count;
static struct delayed_work nfsd_filecache_laundrette;
+static DEFINE_SPINLOCK(laundrette_lock);
+static LIST_HEAD(laundrettes);
-enum nfsd_file_laundrette_ctl {
- NFSD_FILE_LAUNDRETTE_NOFLUSH = 0,
- NFSD_FILE_LAUNDRETTE_MAY_FLUSH
-};
+static void nfsd_file_gc(void);
static void
-nfsd_file_schedule_laundrette(enum nfsd_file_laundrette_ctl ctl)
+nfsd_file_schedule_laundrette(void)
{
long count = atomic_long_read(&nfsd_filecache_count);
if (count == 0 || test_bit(NFSD_FILE_SHUTDOWN, &nfsd_file_lru_flags))
return;
- /* Be more aggressive about scanning if over the threshold */
- if (count > NFSD_FILE_LRU_THRESHOLD)
- mod_delayed_work(system_wq, &nfsd_filecache_laundrette, 0);
- else
- schedule_delayed_work(&nfsd_filecache_laundrette, NFSD_LAUNDRETTE_DELAY);
-
- if (ctl == NFSD_FILE_LAUNDRETTE_NOFLUSH)
- return;
-
- /* ...and don't delay flushing if we're out of control */
- if (count >= NFSD_FILE_LRU_LIMIT)
- flush_delayed_work(&nfsd_filecache_laundrette);
+ queue_delayed_work(system_wq, &nfsd_filecache_laundrette,
+ NFSD_LAUNDRETTE_DELAY);
}
static void
@@ -101,7 +100,7 @@ nfsd_file_mark_free(struct fsnotify_mark *mark)
static struct nfsd_file_mark *
nfsd_file_mark_get(struct nfsd_file_mark *nfm)
{
- if (!atomic_inc_not_zero(&nfm->nfm_ref))
+ if (!refcount_inc_not_zero(&nfm->nfm_ref))
return NULL;
return nfm;
}
@@ -109,8 +108,7 @@ nfsd_file_mark_get(struct nfsd_file_mark *nfm)
static void
nfsd_file_mark_put(struct nfsd_file_mark *nfm)
{
- if (atomic_dec_and_test(&nfm->nfm_ref)) {
-
+ if (refcount_dec_and_test(&nfm->nfm_ref)) {
fsnotify_destroy_mark(&nfm->nfm_mark, nfsd_file_fsnotify_group);
fsnotify_put_mark(&nfm->nfm_mark);
}
@@ -133,9 +131,13 @@ nfsd_file_mark_find_or_create(struct nfsd_file *nf)
struct nfsd_file_mark,
nfm_mark));
mutex_unlock(&nfsd_file_fsnotify_group->mark_mutex);
- fsnotify_put_mark(mark);
- if (likely(nfm))
+ if (nfm) {
+ fsnotify_put_mark(mark);
break;
+ }
+ /* Avoid soft lockup race with nfsd_file_mark_put() */
+ fsnotify_destroy_mark(mark, nfsd_file_fsnotify_group);
+ fsnotify_put_mark(mark);
} else
mutex_unlock(&nfsd_file_fsnotify_group->mark_mutex);
@@ -145,7 +147,7 @@ nfsd_file_mark_find_or_create(struct nfsd_file *nf)
return NULL;
fsnotify_init_mark(&new->nfm_mark, nfsd_file_fsnotify_group);
new->nfm_mark.mask = FS_ATTRIB|FS_DELETE_SELF;
- atomic_set(&new->nfm_ref, 1);
+ refcount_set(&new->nfm_ref, 1);
err = fsnotify_add_inode_mark(&new->nfm_mark, inode, 0);
@@ -183,7 +185,7 @@ nfsd_file_alloc(struct inode *inode, unsigned int may, unsigned int hashval,
nf->nf_flags = 0;
nf->nf_inode = inode;
nf->nf_hashval = hashval;
- atomic_set(&nf->nf_ref, 1);
+ refcount_set(&nf->nf_ref, 1);
nf->nf_may = may & NFSD_FILE_MAY_MASK;
if (may & NFSD_MAY_NOT_BREAK_LEASE) {
if (may & NFSD_MAY_WRITE)
@@ -192,6 +194,7 @@ nfsd_file_alloc(struct inode *inode, unsigned int may, unsigned int hashval,
__set_bit(NFSD_FILE_BREAK_READ, &nf->nf_flags);
}
nf->nf_mark = NULL;
+ init_rwsem(&nf->nf_rwsem);
trace_nfsd_file_alloc(nf);
}
return nf;
@@ -238,13 +241,6 @@ nfsd_file_check_write_error(struct nfsd_file *nf)
return filemap_check_wb_err(file->f_mapping, READ_ONCE(file->f_wb_err));
}
-static bool
-nfsd_file_in_use(struct nfsd_file *nf)
-{
- return nfsd_file_check_writeback(nf) ||
- nfsd_file_check_write_error(nf);
-}
-
static void
nfsd_file_do_unhash(struct nfsd_file *nf)
{
@@ -256,8 +252,6 @@ nfsd_file_do_unhash(struct nfsd_file *nf)
nfsd_reset_boot_verifier(net_generic(nf->nf_net, nfsd_net_id));
--nfsd_file_hashtbl[nf->nf_hashval].nfb_count;
hlist_del_rcu(&nf->nf_node);
- if (!list_empty(&nf->nf_lru))
- list_lru_del(&nfsd_file_lru, &nf->nf_lru);
atomic_long_dec(&nfsd_filecache_count);
}
@@ -266,6 +260,8 @@ nfsd_file_unhash(struct nfsd_file *nf)
{
if (test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
nfsd_file_do_unhash(nf);
+ if (!list_empty(&nf->nf_lru))
+ list_lru_del(&nfsd_file_lru, &nf->nf_lru);
return true;
}
return false;
@@ -283,42 +279,48 @@ nfsd_file_unhash_and_release_locked(struct nfsd_file *nf, struct list_head *disp
if (!nfsd_file_unhash(nf))
return false;
/* keep final reference for nfsd_file_lru_dispose */
- if (atomic_add_unless(&nf->nf_ref, -1, 1))
+ if (refcount_dec_not_one(&nf->nf_ref))
return true;
list_add(&nf->nf_lru, dispose);
return true;
}
-static int
+static void
nfsd_file_put_noref(struct nfsd_file *nf)
{
- int count;
trace_nfsd_file_put(nf);
- count = atomic_dec_return(&nf->nf_ref);
- if (!count) {
+ if (refcount_dec_and_test(&nf->nf_ref)) {
WARN_ON(test_bit(NFSD_FILE_HASHED, &nf->nf_flags));
nfsd_file_free(nf);
}
- return count;
}
void
nfsd_file_put(struct nfsd_file *nf)
{
- bool is_hashed = test_bit(NFSD_FILE_HASHED, &nf->nf_flags) != 0;
- bool unused = !nfsd_file_in_use(nf);
+ bool is_hashed;
set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags);
- if (nfsd_file_put_noref(nf) == 1 && is_hashed && unused)
- nfsd_file_schedule_laundrette(NFSD_FILE_LAUNDRETTE_MAY_FLUSH);
+ if (refcount_read(&nf->nf_ref) > 2 || !nf->nf_file) {
+ nfsd_file_put_noref(nf);
+ return;
+ }
+
+ filemap_flush(nf->nf_file->f_mapping);
+ is_hashed = test_bit(NFSD_FILE_HASHED, &nf->nf_flags) != 0;
+ nfsd_file_put_noref(nf);
+ if (is_hashed)
+ nfsd_file_schedule_laundrette();
+ if (atomic_long_read(&nfsd_filecache_count) >= NFSD_FILE_LRU_LIMIT)
+ nfsd_file_gc();
}
struct nfsd_file *
nfsd_file_get(struct nfsd_file *nf)
{
- if (likely(atomic_inc_not_zero(&nf->nf_ref)))
+ if (likely(refcount_inc_not_zero(&nf->nf_ref)))
return nf;
return NULL;
}
@@ -344,7 +346,7 @@ nfsd_file_dispose_list_sync(struct list_head *dispose)
while(!list_empty(dispose)) {
nf = list_first_entry(dispose, struct nfsd_file, nf_lru);
list_del(&nf->nf_lru);
- if (!atomic_dec_and_test(&nf->nf_ref))
+ if (!refcount_dec_and_test(&nf->nf_ref))
continue;
if (nfsd_file_free(nf))
flush = true;
@@ -353,6 +355,58 @@ nfsd_file_dispose_list_sync(struct list_head *dispose)
flush_delayed_fput();
}
+static void
+nfsd_file_list_remove_disposal(struct list_head *dst,
+ struct nfsd_fcache_disposal *l)
+{
+ spin_lock(&l->lock);
+ list_splice_init(&l->freeme, dst);
+ spin_unlock(&l->lock);
+}
+
+static void
+nfsd_file_list_add_disposal(struct list_head *files, struct net *net)
+{
+ struct nfsd_fcache_disposal *l;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(l, &laundrettes, list) {
+ if (l->net == net) {
+ spin_lock(&l->lock);
+ list_splice_tail_init(files, &l->freeme);
+ spin_unlock(&l->lock);
+ queue_work(nfsd_filecache_wq, &l->work);
+ break;
+ }
+ }
+ rcu_read_unlock();
+}
+
+static void
+nfsd_file_list_add_pernet(struct list_head *dst, struct list_head *src,
+ struct net *net)
+{
+ struct nfsd_file *nf, *tmp;
+
+ list_for_each_entry_safe(nf, tmp, src, nf_lru) {
+ if (nf->nf_net == net)
+ list_move_tail(&nf->nf_lru, dst);
+ }
+}
+
+static void
+nfsd_file_dispose_list_delayed(struct list_head *dispose)
+{
+ LIST_HEAD(list);
+ struct nfsd_file *nf;
+
+ while(!list_empty(dispose)) {
+ nf = list_first_entry(dispose, struct nfsd_file, nf_lru);
+ nfsd_file_list_add_pernet(&list, dispose, nf->nf_net);
+ nfsd_file_list_add_disposal(&list, nf->nf_net);
+ }
+}
+
/*
* Note this can deadlock with nfsd_file_cache_purge.
*/
@@ -375,7 +429,7 @@ nfsd_file_lru_cb(struct list_head *item, struct list_lru_one *lru,
* counter. Here we check the counter and then test and clear the flag.
* That order is deliberate to ensure that we can do this locklessly.
*/
- if (atomic_read(&nf->nf_ref) > 1)
+ if (refcount_read(&nf->nf_ref) > 1)
goto out_skip;
/*
@@ -386,31 +440,51 @@ nfsd_file_lru_cb(struct list_head *item, struct list_lru_one *lru,
goto out_skip;
if (test_and_clear_bit(NFSD_FILE_REFERENCED, &nf->nf_flags))
- goto out_rescan;
+ goto out_skip;
if (!test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags))
goto out_skip;
list_lru_isolate_move(lru, &nf->nf_lru, head);
return LRU_REMOVED;
-out_rescan:
- set_bit(NFSD_FILE_LRU_RESCAN, &nfsd_file_lru_flags);
out_skip:
return LRU_SKIP;
}
-static void
-nfsd_file_lru_dispose(struct list_head *head)
+static unsigned long
+nfsd_file_lru_walk_list(struct shrink_control *sc)
{
- while(!list_empty(head)) {
- struct nfsd_file *nf = list_first_entry(head,
- struct nfsd_file, nf_lru);
- list_del_init(&nf->nf_lru);
+ LIST_HEAD(head);
+ struct nfsd_file *nf;
+ unsigned long ret;
+
+ if (sc)
+ ret = list_lru_shrink_walk(&nfsd_file_lru, sc,
+ nfsd_file_lru_cb, &head);
+ else
+ ret = list_lru_walk(&nfsd_file_lru,
+ nfsd_file_lru_cb,
+ &head, LONG_MAX);
+ list_for_each_entry(nf, &head, nf_lru) {
spin_lock(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock);
nfsd_file_do_unhash(nf);
spin_unlock(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock);
- nfsd_file_put_noref(nf);
}
+ nfsd_file_dispose_list_delayed(&head);
+ return ret;
+}
+
+static void
+nfsd_file_gc(void)
+{
+ nfsd_file_lru_walk_list(NULL);
+}
+
+static void
+nfsd_file_gc_worker(struct work_struct *work)
+{
+ nfsd_file_gc();
+ nfsd_file_schedule_laundrette();
}
static unsigned long
@@ -422,12 +496,7 @@ nfsd_file_lru_count(struct shrinker *s, struct shrink_control *sc)
static unsigned long
nfsd_file_lru_scan(struct shrinker *s, struct shrink_control *sc)
{
- LIST_HEAD(head);
- unsigned long ret;
-
- ret = list_lru_shrink_walk(&nfsd_file_lru, sc, nfsd_file_lru_cb, &head);
- nfsd_file_lru_dispose(&head);
- return ret;
+ return nfsd_file_lru_walk_list(sc);
}
static struct shrinker nfsd_file_shrinker = {
@@ -489,7 +558,7 @@ nfsd_file_close_inode(struct inode *inode)
__nfsd_file_close_inode(inode, hashval, &dispose);
trace_nfsd_file_close_inode(inode, hashval, !list_empty(&dispose));
- nfsd_file_dispose_list(&dispose);
+ nfsd_file_dispose_list_delayed(&dispose);
}
/**
@@ -505,16 +574,11 @@ static void
nfsd_file_delayed_close(struct work_struct *work)
{
LIST_HEAD(head);
+ struct nfsd_fcache_disposal *l = container_of(work,
+ struct nfsd_fcache_disposal, work);
- list_lru_walk(&nfsd_file_lru, nfsd_file_lru_cb, &head, LONG_MAX);
-
- if (test_and_clear_bit(NFSD_FILE_LRU_RESCAN, &nfsd_file_lru_flags))
- nfsd_file_schedule_laundrette(NFSD_FILE_LAUNDRETTE_NOFLUSH);
-
- if (!list_empty(&head)) {
- nfsd_file_lru_dispose(&head);
- flush_delayed_fput();
- }
+ nfsd_file_list_remove_disposal(&head, l);
+ nfsd_file_dispose_list(&head);
}
static int
@@ -575,6 +639,10 @@ nfsd_file_cache_init(void)
if (nfsd_file_hashtbl)
return 0;
+ nfsd_filecache_wq = alloc_workqueue("nfsd_filecache", 0, 0);
+ if (!nfsd_filecache_wq)
+ goto out;
+
nfsd_file_hashtbl = kcalloc(NFSD_FILE_HASH_SIZE,
sizeof(*nfsd_file_hashtbl), GFP_KERNEL);
if (!nfsd_file_hashtbl) {
@@ -628,7 +696,7 @@ nfsd_file_cache_init(void)
spin_lock_init(&nfsd_file_hashtbl[i].nfb_lock);
}
- INIT_DELAYED_WORK(&nfsd_filecache_laundrette, nfsd_file_delayed_close);
+ INIT_DELAYED_WORK(&nfsd_filecache_laundrette, nfsd_file_gc_worker);
out:
return ret;
out_notifier:
@@ -644,6 +712,8 @@ out_err:
nfsd_file_mark_slab = NULL;
kfree(nfsd_file_hashtbl);
nfsd_file_hashtbl = NULL;
+ destroy_workqueue(nfsd_filecache_wq);
+ nfsd_filecache_wq = NULL;
goto out;
}
@@ -682,6 +752,88 @@ nfsd_file_cache_purge(struct net *net)
}
}
+static struct nfsd_fcache_disposal *
+nfsd_alloc_fcache_disposal(struct net *net)
+{
+ struct nfsd_fcache_disposal *l;
+
+ l = kmalloc(sizeof(*l), GFP_KERNEL);
+ if (!l)
+ return NULL;
+ INIT_WORK(&l->work, nfsd_file_delayed_close);
+ l->net = net;
+ spin_lock_init(&l->lock);
+ INIT_LIST_HEAD(&l->freeme);
+ return l;
+}
+
+static void
+nfsd_free_fcache_disposal(struct nfsd_fcache_disposal *l)
+{
+ rcu_assign_pointer(l->net, NULL);
+ cancel_work_sync(&l->work);
+ nfsd_file_dispose_list(&l->freeme);
+ kfree_rcu(l, rcu);
+}
+
+static void
+nfsd_add_fcache_disposal(struct nfsd_fcache_disposal *l)
+{
+ spin_lock(&laundrette_lock);
+ list_add_tail_rcu(&l->list, &laundrettes);
+ spin_unlock(&laundrette_lock);
+}
+
+static void
+nfsd_del_fcache_disposal(struct nfsd_fcache_disposal *l)
+{
+ spin_lock(&laundrette_lock);
+ list_del_rcu(&l->list);
+ spin_unlock(&laundrette_lock);
+}
+
+static int
+nfsd_alloc_fcache_disposal_net(struct net *net)
+{
+ struct nfsd_fcache_disposal *l;
+
+ l = nfsd_alloc_fcache_disposal(net);
+ if (!l)
+ return -ENOMEM;
+ nfsd_add_fcache_disposal(l);
+ return 0;
+}
+
+static void
+nfsd_free_fcache_disposal_net(struct net *net)
+{
+ struct nfsd_fcache_disposal *l;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(l, &laundrettes, list) {
+ if (l->net != net)
+ continue;
+ nfsd_del_fcache_disposal(l);
+ rcu_read_unlock();
+ nfsd_free_fcache_disposal(l);
+ return;
+ }
+ rcu_read_unlock();
+}
+
+int
+nfsd_file_cache_start_net(struct net *net)
+{
+ return nfsd_alloc_fcache_disposal_net(net);
+}
+
+void
+nfsd_file_cache_shutdown_net(struct net *net)
+{
+ nfsd_file_cache_purge(net);
+ nfsd_free_fcache_disposal_net(net);
+}
+
void
nfsd_file_cache_shutdown(void)
{
@@ -706,6 +858,8 @@ nfsd_file_cache_shutdown(void)
nfsd_file_mark_slab = NULL;
kfree(nfsd_file_hashtbl);
nfsd_file_hashtbl = NULL;
+ destroy_workqueue(nfsd_filecache_wq);
+ nfsd_filecache_wq = NULL;
}
static bool
@@ -789,6 +943,7 @@ nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
struct nfsd_file *nf, *new;
struct inode *inode;
unsigned int hashval;
+ bool retry = true;
/* FIXME: skip this if fh_dentry is already set? */
status = fh_verify(rqstp, fhp, S_IFREG,
@@ -824,6 +979,11 @@ wait_for_construction:
/* Did construction of this file fail? */
if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
+ if (!retry) {
+ status = nfserr_jukebox;
+ goto out;
+ }
+ retry = false;
nfsd_file_put_noref(nf);
goto retry;
}
@@ -858,7 +1018,7 @@ out:
open_file:
nf = new;
/* Take reference for the hashtable */
- atomic_inc(&nf->nf_ref);
+ refcount_inc(&nf->nf_ref);
__set_bit(NFSD_FILE_HASHED, &nf->nf_flags);
__set_bit(NFSD_FILE_PENDING, &nf->nf_flags);
list_lru_add(&nfsd_file_lru, &nf->nf_lru);
@@ -867,7 +1027,8 @@ open_file:
nfsd_file_hashtbl[hashval].nfb_maxcount = max(nfsd_file_hashtbl[hashval].nfb_maxcount,
nfsd_file_hashtbl[hashval].nfb_count);
spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock);
- atomic_long_inc(&nfsd_filecache_count);
+ if (atomic_long_inc_return(&nfsd_filecache_count) >= NFSD_FILE_LRU_THRESHOLD)
+ nfsd_file_gc();
nf->nf_mark = nfsd_file_mark_find_or_create(nf);
if (nf->nf_mark)