1 files changed, 65 insertions, 48 deletions

diff --git a/fs/netfs/objects.c b/fs/netfs/objects.c
index f4a642727479..b8c4918d3dcd 100644
--- a/fs/netfs/objects.c
+++ b/fs/netfs/objects.c
@@ -10,6 +10,8 @@
 #include <linux/delay.h>
 #include "internal.h"
 
+static void netfs_free_request(struct work_struct *work);
+
 /*
  * Allocate an I/O request and initialise it.
  */
@@ -24,10 +26,6 @@ struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
 	struct netfs_io_request *rreq;
 	mempool_t *mempool = ctx->ops->request_pool ?: &netfs_request_pool;
 	struct kmem_cache *cache = mempool->pool_data;
-	bool is_unbuffered = (origin == NETFS_UNBUFFERED_WRITE ||
-			      origin == NETFS_DIO_READ ||
-			      origin == NETFS_DIO_WRITE);
-	bool cached = !is_unbuffered && netfs_is_cache_enabled(ctx);
 	int ret;
 
 	for (;;) {
@@ -38,9 +36,9 @@ struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
 	}
 
 	memset(rreq, 0, kmem_cache_size(cache));
+	INIT_WORK(&rreq->cleanup_work, netfs_free_request);
 	rreq->start	= start;
 	rreq->len	= len;
-	rreq->upper_len	= len;
 	rreq->origin	= origin;
 	rreq->netfs_ops	= ctx->ops;
 	rreq->mapping	= mapping;
@@ -48,22 +46,28 @@ struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
 	rreq->i_size	= i_size_read(inode);
 	rreq->debug_id	= atomic_inc_return(&debug_ids);
 	rreq->wsize	= INT_MAX;
+	rreq->io_streams[0].sreq_max_len = ULONG_MAX;
+	rreq->io_streams[0].sreq_max_segs = 0;
 	spin_lock_init(&rreq->lock);
 	INIT_LIST_HEAD(&rreq->io_streams[0].subrequests);
 	INIT_LIST_HEAD(&rreq->io_streams[1].subrequests);
-	INIT_LIST_HEAD(&rreq->subrequests);
-	INIT_WORK(&rreq->work, NULL);
-	refcount_set(&rreq->ref, 1);
+	init_waitqueue_head(&rreq->waitq);
+	refcount_set(&rreq->ref, 2);
 
-	__set_bit(NETFS_RREQ_IN_PROGRESS, &rreq->flags);
-	if (cached) {
-		__set_bit(NETFS_RREQ_WRITE_TO_CACHE, &rreq->flags);
-		if (test_bit(NETFS_ICTX_USE_PGPRIV2, &ctx->flags))
-			/* Filesystem uses deprecated PG_private_2 marking. */
-			__set_bit(NETFS_RREQ_USE_PGPRIV2, &rreq->flags);
+	if (origin == NETFS_READAHEAD ||
+	    origin == NETFS_READPAGE ||
+	    origin == NETFS_READ_GAPS ||
+	    origin == NETFS_READ_SINGLE ||
+	    origin == NETFS_READ_FOR_WRITE ||
+	    origin == NETFS_UNBUFFERED_READ ||
+	    origin == NETFS_DIO_READ) {
+		INIT_WORK(&rreq->work, netfs_read_collection_worker);
+		rreq->io_streams[0].avail = true;
+	} else {
+		INIT_WORK(&rreq->work, netfs_write_collection_worker);
 	}
-	if (file && file->f_flags & O_NONBLOCK)
-		__set_bit(NETFS_RREQ_NONBLOCK, &rreq->flags);
+
+	__set_bit(NETFS_RREQ_IN_PROGRESS, &rreq->flags);
 	if (rreq->netfs_ops->init_request) {
 		ret = rreq->netfs_ops->init_request(rreq, file);
 		if (ret < 0) {
@@ -73,7 +77,7 @@ struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
 	}
 
 	atomic_inc(&ctx->io_count);
-	trace_netfs_rreq_ref(rreq->debug_id, 1, netfs_rreq_trace_new);
+	trace_netfs_rreq_ref(rreq->debug_id, refcount_read(&rreq->ref), netfs_rreq_trace_new);
 	netfs_proc_add_rreq(rreq);
 	netfs_stat(&netfs_n_rh_rreq);
 	return rreq;
@@ -87,28 +91,19 @@ void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace
 	trace_netfs_rreq_ref(rreq->debug_id, r + 1, what);
 }
 
-void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async)
+void netfs_clear_subrequests(struct netfs_io_request *rreq)
 {
 	struct netfs_io_subrequest *subreq;
 	struct netfs_io_stream *stream;
 	int s;
 
-	while (!list_empty(&rreq->subrequests)) {
-		subreq = list_first_entry(&rreq->subrequests,
-					  struct netfs_io_subrequest, rreq_link);
-		list_del(&subreq->rreq_link);
-		netfs_put_subrequest(subreq, was_async,
-				     netfs_sreq_trace_put_clear);
-	}
-
 	for (s = 0; s < ARRAY_SIZE(rreq->io_streams); s++) {
 		stream = &rreq->io_streams[s];
 		while (!list_empty(&stream->subrequests)) {
 			subreq = list_first_entry(&stream->subrequests,
 						  struct netfs_io_subrequest, rreq_link);
 			list_del(&subreq->rreq_link);
-			netfs_put_subrequest(subreq, was_async,
-					     netfs_sreq_trace_put_clear);
+			netfs_put_subrequest(subreq, netfs_sreq_trace_put_clear);
 		}
 	}
 }
@@ -121,16 +116,20 @@ static void netfs_free_request_rcu(struct rcu_head *rcu)
 	netfs_stat_d(&netfs_n_rh_rreq);
 }
 
-static void netfs_free_request(struct work_struct *work)
+static void netfs_deinit_request(struct netfs_io_request *rreq)
 {
-	struct netfs_io_request *rreq =
-		container_of(work, struct netfs_io_request, work);
 	struct netfs_inode *ictx = netfs_inode(rreq->inode);
 	unsigned int i;
 
 	trace_netfs_rreq(rreq, netfs_rreq_trace_free);
+
+	/* Cancel/flush the result collection worker.  That does not carry a
+	 * ref of its own, so we must wait for it somewhere.
+	 */
+	cancel_work_sync(&rreq->work);
+
 	netfs_proc_del_rreq(rreq);
-	netfs_clear_subrequests(rreq, false);
+	netfs_clear_subrequests(rreq);
 	if (rreq->netfs_ops->free_request)
 		rreq->netfs_ops->free_request(rreq);
 	if (rreq->cache_resources.ops)
@@ -144,14 +143,22 @@ static void netfs_free_request(struct work_struct *work)
 		}
 		kvfree(rreq->direct_bv);
 	}
+	rolling_buffer_clear(&rreq->buffer);
 
 	if (atomic_dec_and_test(&ictx->io_count))
 		wake_up_var(&ictx->io_count);
+}
+
+static void netfs_free_request(struct work_struct *work)
+{
+	struct netfs_io_request *rreq =
+		container_of(work, struct netfs_io_request, cleanup_work);
+
+	netfs_deinit_request(rreq);
 	call_rcu(&rreq->rcu, netfs_free_request_rcu);
 }
 
-void netfs_put_request(struct netfs_io_request *rreq, bool was_async,
-		       enum netfs_rreq_ref_trace what)
+void netfs_put_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what)
 {
 	unsigned int debug_id;
 	bool dead;
@@ -161,19 +168,30 @@ void netfs_put_request(struct netfs_io_request *rreq, bool was_async,
 		debug_id = rreq->debug_id;
 		dead = __refcount_dec_and_test(&rreq->ref, &r);
 		trace_netfs_rreq_ref(debug_id, r - 1, what);
-		if (dead) {
-			if (was_async) {
-				rreq->work.func = netfs_free_request;
-				if (!queue_work(system_unbound_wq, &rreq->work))
-					BUG();
-			} else {
-				netfs_free_request(&rreq->work);
-			}
-		}
+		if (dead)
+			WARN_ON(!queue_work(system_dfl_wq, &rreq->cleanup_work));
 	}
 }
 
 /*
+ * Free a request (synchronously) that was just allocated but has
+ * failed before it could be submitted.
+ */
+void netfs_put_failed_request(struct netfs_io_request *rreq)
+{
+	int r = refcount_read(&rreq->ref);
+
+	/* new requests have two references (see
+	 * netfs_alloc_request(), and this function is only allowed on
+	 * new request objects
+	 */
+	WARN_ON_ONCE(r != 2);
+
+	trace_netfs_rreq_ref(rreq->debug_id, r, netfs_rreq_trace_put_failed);
+	netfs_free_request(&rreq->cleanup_work);
+}
+
+/*
  * Allocate and partially initialise an I/O request structure.
  */
 struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq)
@@ -211,8 +229,7 @@ void netfs_get_subrequest(struct netfs_io_subrequest *subreq,
 			     what);
 }
 
-static void netfs_free_subrequest(struct netfs_io_subrequest *subreq,
-				  bool was_async)
+static void netfs_free_subrequest(struct netfs_io_subrequest *subreq)
 {
 	struct netfs_io_request *rreq = subreq->rreq;
 
@@ -221,10 +238,10 @@ static void netfs_free_subrequest(struct netfs_io_subrequest *subreq,
 		rreq->netfs_ops->free_subrequest(subreq);
 	mempool_free(subreq, rreq->netfs_ops->subrequest_pool ?: &netfs_subrequest_pool);
 	netfs_stat_d(&netfs_n_rh_sreq);
-	netfs_put_request(rreq, was_async, netfs_rreq_trace_put_subreq);
+	netfs_put_request(rreq, netfs_rreq_trace_put_subreq);
 }
 
-void netfs_put_subrequest(struct netfs_io_subrequest *subreq, bool was_async,
+void netfs_put_subrequest(struct netfs_io_subrequest *subreq,
 			  enum netfs_sreq_ref_trace what)
 {
 	unsigned int debug_index = subreq->debug_index;
@@ -235,5 +252,5 @@ void netfs_put_subrequest(struct netfs_io_subrequest *subreq, bool was_async,
 	dead = __refcount_dec_and_test(&subreq->ref, &r);
 	trace_netfs_sreq_ref(debug_id, debug_index, r - 1, what);
 	if (dead)
-		netfs_free_subrequest(subreq, was_async);
+		netfs_free_subrequest(subreq);
 }