fuse: Protect ff->reserved_req via corresponding fi->lock

This is rather natural action after previous patches, and it just decreases
load of fc->lock.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

2 files changed, 10 insertions, 5 deletions

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index ed9318d4e7dc..5a7309427e0e 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -251,17 +251,18 @@ static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
                                          struct file *file)
 {
         struct fuse_req *req = NULL;
+        struct fuse_inode *fi = get_fuse_inode(file_inode(file));
         struct fuse_file *ff = file->private_data;
 
         do {
                 wait_event(fc->reserved_req_waitq, ff->reserved_req);
-                spin_lock(&fc->lock);
+                spin_lock(&fi->lock);
                 if (ff->reserved_req) {
                         req = ff->reserved_req;
                         ff->reserved_req = NULL;
                         req->stolen_file = get_file(file);
                 }
-                spin_unlock(&fc->lock);
+                spin_unlock(&fi->lock);
         } while (!req);
 
         return req;
@@ -273,16 +274,17 @@ static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
 static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
 {
         struct file *file = req->stolen_file;
+        struct fuse_inode *fi = get_fuse_inode(file_inode(file));
         struct fuse_file *ff = file->private_data;
 
         WARN_ON(req->max_pages);
-        spin_lock(&fc->lock);
+        spin_lock(&fi->lock);
         memset(req, 0, sizeof(*req));
         fuse_request_init(req, NULL, NULL, 0);
         BUG_ON(ff->reserved_req);
         ff->reserved_req = req;
         wake_up_all(&fc->reserved_req_waitq);
-        spin_unlock(&fc->lock);
+        spin_unlock(&fi->lock);
         fput(file);
 }
 
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 1c610b65b1bf..4fdd098e422d 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -166,7 +166,10 @@ struct fuse_file {
         /** Fuse connection for this file */
         struct fuse_conn *fc;
 
-        /** Request reserved for flush and release */
+        /*
+         * Request reserved for flush and release.
+         * Modified under relative fuse_inode::lock.
+         */
         struct fuse_req *reserved_req;
 
         /** Kernel file handle guaranteed to be unique */