[patch 0/3] fuse: update for 2.6.25

[patch 0/3] fuse: update for 2.6.25

[Miklos Szeredi]

Here's one small fix, one cleanup and one in preparation for writable
mmap support (but which makes sense on it's own as well).

Please apply.

Thanks,
Miklos

--

[patch 1/3] fuse: fix attribute caching after create

[Miklos Szeredi]

[-- Attachment #1: fuse_create_fix.patch --]
[-- Type: text/plain, Size: 727 bytes --]

From: Miklos Szeredi <mszeredi@suse.cz>

Invalidate attributes on create, since st_ctime is updated.  Reported
by Szabolcs Szakacsits

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---

Index: linux/fs/fuse/dir.c
===================================================================
--- linux.orig/fs/fuse/dir.c	2008-01-29 17:12:56.000000000 +0100
+++ linux/fs/fuse/dir.c	2008-01-29 17:13:04.000000000 +0100
@@ -416,6 +416,7 @@ static int fuse_create_open(struct inode
 	fuse_put_request(fc, forget_req);
 	d_instantiate(entry, inode);
 	fuse_change_entry_timeout(entry, &outentry);
+	fuse_invalidate_attr(dir);
 	file = lookup_instantiate_filp(nd, entry, generic_file_open);
 	if (IS_ERR(file)) {
 		ff->fh = outopen.fh;

--

[patch 2/3] fuse: save space in struct fuse_req

[Miklos Szeredi]

[-- Attachment #1: fuse_move_to_union.patch --]
[-- Type: text/plain, Size: 3091 bytes --]

From: Miklos Szeredi <mszeredi@suse.cz>

Move the fields 'dentry' and 'vfsmount' into the request specific
union, since these are only used for the RELEASE request.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---

Index: linux/fs/fuse/file.c
===================================================================
--- linux.orig/fs/fuse/file.c	2008-01-29 17:12:56.000000000 +0100
+++ linux/fs/fuse/file.c	2008-01-29 17:13:06.000000000 +0100
@@ -77,8 +77,8 @@ static struct fuse_file *fuse_file_get(s
 
 static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
 {
-	dput(req->dentry);
-	mntput(req->vfsmount);
+	dput(req->misc.release.dentry);
+	mntput(req->misc.release.vfsmount);
 	fuse_put_request(fc, req);
 }
 
@@ -86,7 +86,8 @@ static void fuse_file_put(struct fuse_fi
 {
 	if (atomic_dec_and_test(&ff->count)) {
 		struct fuse_req *req = ff->reserved_req;
-		struct fuse_conn *fc = get_fuse_conn(req->dentry->d_inode);
+		struct inode *inode = req->misc.release.dentry->d_inode;
+		struct fuse_conn *fc = get_fuse_conn(inode);
 		req->end = fuse_release_end;
 		request_send_background(fc, req);
 		kfree(ff);
@@ -137,7 +138,7 @@ int fuse_open_common(struct inode *inode
 void fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags, int opcode)
 {
 	struct fuse_req *req = ff->reserved_req;
-	struct fuse_release_in *inarg = &req->misc.release_in;
+	struct fuse_release_in *inarg = &req->misc.release.in;
 
 	inarg->fh = ff->fh;
 	inarg->flags = flags;
@@ -153,13 +154,14 @@ int fuse_release_common(struct inode *in
 	struct fuse_file *ff = file->private_data;
 	if (ff) {
 		struct fuse_conn *fc = get_fuse_conn(inode);
+		struct fuse_req *req = ff->reserved_req;
 
 		fuse_release_fill(ff, get_node_id(inode), file->f_flags,
 				  isdir ? FUSE_RELEASEDIR : FUSE_RELEASE);
 
 		/* Hold vfsmount and dentry until release is finished */
-		ff->reserved_req->vfsmount = mntget(file->f_path.mnt);
-		ff->reserved_req->dentry = dget(file->f_path.dentry);
+		req->misc.release.vfsmount = mntget(file->f_path.mnt);
+		req->misc.release.dentry = dget(file->f_path.dentry);
 
 		spin_lock(&fc->lock);
 		list_del(&ff->write_entry);
Index: linux/fs/fuse/fuse_i.h
===================================================================
--- linux.orig/fs/fuse/fuse_i.h	2008-01-29 17:12:56.000000000 +0100
+++ linux/fs/fuse/fuse_i.h	2008-01-29 17:13:06.000000000 +0100
@@ -215,7 +215,11 @@ struct fuse_req {
 	/** Data for asynchronous requests */
 	union {
 		struct fuse_forget_in forget_in;
-		struct fuse_release_in release_in;
+		struct {
+			struct fuse_release_in in;
+			struct vfsmount *vfsmount;
+			struct dentry *dentry;
+		} release;
 		struct fuse_init_in init_in;
 		struct fuse_init_out init_out;
 		struct fuse_read_in read_in;
@@ -238,12 +242,6 @@ struct fuse_req {
 	/** File used in the request (or NULL) */
 	struct fuse_file *ff;
 
-	/** vfsmount used in release */
-	struct vfsmount *vfsmount;
-
-	/** dentry used in release */
-	struct dentry *dentry;
-
 	/** Request completion callback */
 	void (*end)(struct fuse_conn *, struct fuse_req *);
 

--

[patch 3/3] fuse: limit queued background requests

[Miklos Szeredi]

[-- Attachment #1: fuse_background_limit.patch --]
[-- Type: text/plain, Size: 5586 bytes --]

From: Miklos Szeredi <mszeredi@suse.cz>

Libfuse basically creates a new thread for each new request.  This is
fine for synchronous requests, which are naturally limited.  However
background requests (especially writepage) can cause a thread creation
storm.

To avoid this, limit the number of background requests available to
userspace.

This is done by introducing another queue for background requests, and
a counter for the number of "active" requests, which are currently
available for userspace.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---

Index: linux/fs/fuse/dev.c
===================================================================
--- linux.orig/fs/fuse/dev.c	2008-01-29 17:12:56.000000000 +0100
+++ linux/fs/fuse/dev.c	2008-01-29 17:15:15.000000000 +0100
@@ -201,6 +201,55 @@ void fuse_put_request(struct fuse_conn *
 	}
 }
 
+static unsigned len_args(unsigned numargs, struct fuse_arg *args)
+{
+	unsigned nbytes = 0;
+	unsigned i;
+
+	for (i = 0; i < numargs; i++)
+		nbytes += args[i].size;
+
+	return nbytes;
+}
+
+static u64 fuse_get_unique(struct fuse_conn *fc)
+{
+	fc->reqctr++;
+	/* zero is special */
+	if (fc->reqctr == 0)
+		fc->reqctr = 1;
+
+	return fc->reqctr;
+}
+
+static void queue_request(struct fuse_conn *fc, struct fuse_req *req)
+{
+	req->in.h.unique = fuse_get_unique(fc);
+	req->in.h.len = sizeof(struct fuse_in_header) +
+		len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
+	list_add_tail(&req->list, &fc->pending);
+	req->state = FUSE_REQ_PENDING;
+	if (!req->waiting) {
+		req->waiting = 1;
+		atomic_inc(&fc->num_waiting);
+	}
+	wake_up(&fc->waitq);
+	kill_fasync(&fc->fasync, SIGIO, POLL_IN);
+}
+
+static void flush_bg_queue(struct fuse_conn *fc)
+{
+	while (fc->active_background < FUSE_MAX_BACKGROUND &&
+	       !list_empty(&fc->bg_queue)) {
+		struct fuse_req *req;
+
+		req = list_entry(fc->bg_queue.next, struct fuse_req, list);
+		list_del(&req->list);
+		fc->active_background++;
+		queue_request(fc, req);
+	}
+}
+
 /*
  * This function is called when a request is finished.  Either a reply
  * has arrived or it was aborted (and not yet sent) or some error
@@ -229,6 +278,8 @@ static void request_end(struct fuse_conn
 			clear_bdi_congested(&fc->bdi, WRITE);
 		}
 		fc->num_background--;
+		fc->active_background--;
+		flush_bg_queue(fc);
 	}
 	spin_unlock(&fc->lock);
 	wake_up(&req->waitq);
@@ -320,42 +371,6 @@ static void request_wait_answer(struct f
 	}
 }
 
-static unsigned len_args(unsigned numargs, struct fuse_arg *args)
-{
-	unsigned nbytes = 0;
-	unsigned i;
-
-	for (i = 0; i < numargs; i++)
-		nbytes += args[i].size;
-
-	return nbytes;
-}
-
-static u64 fuse_get_unique(struct fuse_conn *fc)
- {
- 	fc->reqctr++;
- 	/* zero is special */
- 	if (fc->reqctr == 0)
- 		fc->reqctr = 1;
-
-	return fc->reqctr;
-}
-
-static void queue_request(struct fuse_conn *fc, struct fuse_req *req)
-{
-	req->in.h.unique = fuse_get_unique(fc);
-	req->in.h.len = sizeof(struct fuse_in_header) +
-		len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
-	list_add_tail(&req->list, &fc->pending);
-	req->state = FUSE_REQ_PENDING;
-	if (!req->waiting) {
-		req->waiting = 1;
-		atomic_inc(&fc->num_waiting);
-	}
-	wake_up(&fc->waitq);
-	kill_fasync(&fc->fasync, SIGIO, POLL_IN);
-}
-
 void request_send(struct fuse_conn *fc, struct fuse_req *req)
 {
 	req->isreply = 1;
@@ -375,20 +390,26 @@ void request_send(struct fuse_conn *fc, 
 	spin_unlock(&fc->lock);
 }
 
+static void request_send_nowait_locked(struct fuse_conn *fc,
+				       struct fuse_req *req)
+{
+	req->background = 1;
+	fc->num_background++;
+	if (fc->num_background == FUSE_MAX_BACKGROUND)
+		fc->blocked = 1;
+	if (fc->num_background == FUSE_CONGESTION_THRESHOLD) {
+		set_bdi_congested(&fc->bdi, READ);
+		set_bdi_congested(&fc->bdi, WRITE);
+	}
+	list_add_tail(&req->list, &fc->bg_queue);
+	flush_bg_queue(fc);
+}
+
 static void request_send_nowait(struct fuse_conn *fc, struct fuse_req *req)
 {
 	spin_lock(&fc->lock);
 	if (fc->connected) {
-		req->background = 1;
-		fc->num_background++;
-		if (fc->num_background == FUSE_MAX_BACKGROUND)
-			fc->blocked = 1;
-		if (fc->num_background == FUSE_CONGESTION_THRESHOLD) {
-			set_bdi_congested(&fc->bdi, READ);
-			set_bdi_congested(&fc->bdi, WRITE);
-		}
-
-		queue_request(fc, req);
+		request_send_nowait_locked(fc, req);
 		spin_unlock(&fc->lock);
 	} else {
 		req->out.h.error = -ENOTCONN;
Index: linux/fs/fuse/fuse_i.h
===================================================================
--- linux.orig/fs/fuse/fuse_i.h	2008-01-29 17:13:06.000000000 +0100
+++ linux/fs/fuse/fuse_i.h	2008-01-29 17:14:23.000000000 +0100
@@ -296,6 +296,12 @@ struct fuse_conn {
 	/** Number of requests currently in the background */
 	unsigned num_background;
 
+	/** Number of background requests currently queued for userspace */
+	unsigned active_background;
+
+	/** The list of background requests set aside for later queuing */
+	struct list_head bg_queue;
+
 	/** Pending interrupts */
 	struct list_head interrupts;
 
Index: linux/fs/fuse/inode.c
===================================================================
--- linux.orig/fs/fuse/inode.c	2008-01-29 17:12:56.000000000 +0100
+++ linux/fs/fuse/inode.c	2008-01-29 17:14:23.000000000 +0100
@@ -465,6 +465,7 @@ static struct fuse_conn *new_conn(struct
 		INIT_LIST_HEAD(&fc->processing);
 		INIT_LIST_HEAD(&fc->io);
 		INIT_LIST_HEAD(&fc->interrupts);
+		INIT_LIST_HEAD(&fc->bg_queue);
 		atomic_set(&fc->num_waiting, 0);
 		fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
 		fc->bdi.unplug_io_fn = default_unplug_io_fn;

--