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From:   Jeff Layton <jlayton@kernel.org>
To:     chuck.lever@oracle.com
Cc:     neilb@suse.de, linux-nfs@vger.kernel.org
Subject: [PATCH v5 2/5] nfsd: reorganize filecache.c
Date:   Tue,  1 Nov 2022 10:46:44 -0400
Message-Id: <20221101144647.136696-3-jlayton@kernel.org>
In-Reply-To: <20221101144647.136696-1-jlayton@kernel.org>
References: <20221101144647.136696-1-jlayton@kernel.org>
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In a coming patch, we're going to rework how the filecache refcounting
works. Move some code around in the function to reduce the churn in the
later patches, and rename some of the functions with (hopefully) clearer
names. This should introduce no functional changes.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/nfsd/filecache.c | 135 ++++++++++++++++++++++----------------------
 fs/nfsd/trace.h     |   4 +-
 2 files changed, 70 insertions(+), 69 deletions(-)

diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index 90e62042d6d6..0bf3727455e2 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -311,16 +311,59 @@ nfsd_file_alloc(struct nfsd_file_lookup_key *key, unsigned int may)
 	return nf;
 }
 
+static void
+nfsd_file_fsync(struct nfsd_file *nf)
+{
+	struct file *file = nf->nf_file;
+
+	if (!file || !(file->f_mode & FMODE_WRITE))
+		return;
+	if (vfs_fsync(file, 1) != 0)
+		nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id));
+}
+
+static int
+nfsd_file_check_write_error(struct nfsd_file *nf)
+{
+	struct file *file = nf->nf_file;
+
+	if (!file || !(file->f_mode & FMODE_WRITE))
+		return 0;
+	return filemap_check_wb_err(file->f_mapping, READ_ONCE(file->f_wb_err));
+}
+
+static void
+nfsd_file_hash_remove(struct nfsd_file *nf)
+{
+	trace_nfsd_file_unhash(nf);
+
+	if (nfsd_file_check_write_error(nf))
+		nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id));
+	rhashtable_remove_fast(&nfsd_file_rhash_tbl, &nf->nf_rhash,
+			       nfsd_file_rhash_params);
+}
+
+static bool
+nfsd_file_unhash(struct nfsd_file *nf)
+{
+	if (test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
+		nfsd_file_hash_remove(nf);
+		return true;
+	}
+	return false;
+}
+
 static bool
 nfsd_file_free(struct nfsd_file *nf)
 {
 	s64 age = ktime_to_ms(ktime_sub(ktime_get(), nf->nf_birthtime));
 	bool flush = false;
 
+	trace_nfsd_file_free(nf);
+
 	this_cpu_inc(nfsd_file_releases);
 	this_cpu_add(nfsd_file_total_age, age);
 
-	trace_nfsd_file_put_final(nf);
 	if (nf->nf_mark)
 		nfsd_file_mark_put(nf->nf_mark);
 	if (nf->nf_file) {
@@ -354,27 +397,6 @@ nfsd_file_check_writeback(struct nfsd_file *nf)
 		mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK);
 }
 
-static int
-nfsd_file_check_write_error(struct nfsd_file *nf)
-{
-	struct file *file = nf->nf_file;
-
-	if (!file || !(file->f_mode & FMODE_WRITE))
-		return 0;
-	return filemap_check_wb_err(file->f_mapping, READ_ONCE(file->f_wb_err));
-}
-
-static void
-nfsd_file_flush(struct nfsd_file *nf)
-{
-	struct file *file = nf->nf_file;
-
-	if (!file || !(file->f_mode & FMODE_WRITE))
-		return;
-	if (vfs_fsync(file, 1) != 0)
-		nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id));
-}
-
 static void nfsd_file_lru_add(struct nfsd_file *nf)
 {
 	set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags);
@@ -388,31 +410,18 @@ static void nfsd_file_lru_remove(struct nfsd_file *nf)
 		trace_nfsd_file_lru_del(nf);
 }
 
-static void
-nfsd_file_hash_remove(struct nfsd_file *nf)
-{
-	trace_nfsd_file_unhash(nf);
-
-	if (nfsd_file_check_write_error(nf))
-		nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id));
-	rhashtable_remove_fast(&nfsd_file_rhash_tbl, &nf->nf_rhash,
-			       nfsd_file_rhash_params);
-}
-
-static bool
-nfsd_file_unhash(struct nfsd_file *nf)
+struct nfsd_file *
+nfsd_file_get(struct nfsd_file *nf)
 {
-	if (test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
-		nfsd_file_hash_remove(nf);
-		return true;
-	}
-	return false;
+	if (likely(refcount_inc_not_zero(&nf->nf_ref)))
+		return nf;
+	return NULL;
 }
 
 static void
-nfsd_file_unhash_and_dispose(struct nfsd_file *nf, struct list_head *dispose)
+nfsd_file_unhash_and_queue(struct nfsd_file *nf, struct list_head *dispose)
 {
-	trace_nfsd_file_unhash_and_dispose(nf);
+	trace_nfsd_file_unhash_and_queue(nf);
 	if (nfsd_file_unhash(nf)) {
 		/* caller must call nfsd_file_dispose_list() later */
 		nfsd_file_lru_remove(nf);
@@ -450,7 +459,7 @@ nfsd_file_put(struct nfsd_file *nf)
 		nfsd_file_unhash_and_put(nf);
 
 	if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) {
-		nfsd_file_flush(nf);
+		nfsd_file_fsync(nf);
 		nfsd_file_put_noref(nf);
 	} else if (nf->nf_file && test_bit(NFSD_FILE_GC, &nf->nf_flags)) {
 		nfsd_file_put_noref(nf);
@@ -459,14 +468,6 @@ nfsd_file_put(struct nfsd_file *nf)
 		nfsd_file_put_noref(nf);
 }
 
-struct nfsd_file *
-nfsd_file_get(struct nfsd_file *nf)
-{
-	if (likely(refcount_inc_not_zero(&nf->nf_ref)))
-		return nf;
-	return NULL;
-}
-
 static void
 nfsd_file_dispose_list(struct list_head *dispose)
 {
@@ -475,7 +476,7 @@ nfsd_file_dispose_list(struct list_head *dispose)
 	while(!list_empty(dispose)) {
 		nf = list_first_entry(dispose, struct nfsd_file, nf_lru);
 		list_del_init(&nf->nf_lru);
-		nfsd_file_flush(nf);
+		nfsd_file_fsync(nf);
 		nfsd_file_put_noref(nf);
 	}
 }
@@ -489,7 +490,7 @@ 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_init(&nf->nf_lru);
-		nfsd_file_flush(nf);
+		nfsd_file_fsync(nf);
 		if (!refcount_dec_and_test(&nf->nf_ref))
 			continue;
 		if (nfsd_file_free(nf))
@@ -689,7 +690,7 @@ __nfsd_file_close_inode(struct inode *inode, struct list_head *dispose)
 				       nfsd_file_rhash_params);
 		if (!nf)
 			break;
-		nfsd_file_unhash_and_dispose(nf, dispose);
+		nfsd_file_unhash_and_queue(nf, dispose);
 		count++;
 	} while (1);
 	rcu_read_unlock();
@@ -697,37 +698,37 @@ __nfsd_file_close_inode(struct inode *inode, struct list_head *dispose)
 }
 
 /**
- * nfsd_file_close_inode_sync - attempt to forcibly close a nfsd_file
+ * nfsd_file_close_inode - attempt a delayed close of a nfsd_file
  * @inode: inode of the file to attempt to remove
  *
- * Unhash and put, then flush and fput all cache items associated with @inode.
+ * Unhash and put all cache item associated with @inode.
  */
-void
-nfsd_file_close_inode_sync(struct inode *inode)
+static void
+nfsd_file_close_inode(struct inode *inode)
 {
 	LIST_HEAD(dispose);
 	unsigned int count;
 
 	count = __nfsd_file_close_inode(inode, &dispose);
-	trace_nfsd_file_close_inode_sync(inode, count);
-	nfsd_file_dispose_list_sync(&dispose);
+	trace_nfsd_file_close_inode(inode, count);
+	nfsd_file_dispose_list_delayed(&dispose);
 }
 
 /**
- * nfsd_file_close_inode - attempt a delayed close of a nfsd_file
+ * nfsd_file_close_inode_sync - attempt to forcibly close a nfsd_file
  * @inode: inode of the file to attempt to remove
  *
- * Unhash and put all cache item associated with @inode.
+ * Unhash and put, then flush and fput all cache items associated with @inode.
  */
-static void
-nfsd_file_close_inode(struct inode *inode)
+void
+nfsd_file_close_inode_sync(struct inode *inode)
 {
 	LIST_HEAD(dispose);
 	unsigned int count;
 
 	count = __nfsd_file_close_inode(inode, &dispose);
-	trace_nfsd_file_close_inode(inode, count);
-	nfsd_file_dispose_list_delayed(&dispose);
+	trace_nfsd_file_close_inode_sync(inode, count);
+	nfsd_file_dispose_list_sync(&dispose);
 }
 
 /**
@@ -891,7 +892,7 @@ __nfsd_file_cache_purge(struct net *net)
 		nf = rhashtable_walk_next(&iter);
 		while (!IS_ERR_OR_NULL(nf)) {
 			if (!net || nf->nf_net == net)
-				nfsd_file_unhash_and_dispose(nf, &dispose);
+				nfsd_file_unhash_and_queue(nf, &dispose);
 			nf = rhashtable_walk_next(&iter);
 		}
 
diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index b09ab4f92d43..940252482fd4 100644
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -903,10 +903,10 @@ DEFINE_EVENT(nfsd_file_class, name, \
 	TP_PROTO(struct nfsd_file *nf), \
 	TP_ARGS(nf))
 
-DEFINE_NFSD_FILE_EVENT(nfsd_file_put_final);
+DEFINE_NFSD_FILE_EVENT(nfsd_file_free);
 DEFINE_NFSD_FILE_EVENT(nfsd_file_unhash);
 DEFINE_NFSD_FILE_EVENT(nfsd_file_put);
-DEFINE_NFSD_FILE_EVENT(nfsd_file_unhash_and_dispose);
+DEFINE_NFSD_FILE_EVENT(nfsd_file_unhash_and_queue);
 
 TRACE_EVENT(nfsd_file_alloc,
 	TP_PROTO(
-- 
2.38.1