Commit d4993774 authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

fuse: stop copying args to fuse_req 



No need to duplicate the argument arrays in fuse_req, so just dereference
req->args instead of copying to the fuse_req internal ones.

This allows further cleanup of the fuse_req structure.

Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent 145b673b

fs/fuse/dev.c

+26 −54
Original line number Diff line number Diff line
@@ -202,7 +202,8 @@ static unsigned int fuse_req_hash(u64 unique) 
static void queue_request(struct fuse_iqueue *fiq, struct fuse_req *req)

{

	req->in.h.len = sizeof(struct fuse_in_header) +

		len_args(req->in.numargs, (struct fuse_arg *) req->in.args);

		len_args(req->args->in_numargs,

			 (struct fuse_arg *) req->args->in_args);

	list_add_tail(&req->list, &fiq->pending);

	wake_up(&fiq->waitq);

	kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
@@ -257,6 +258,7 @@ static void flush_bg_queue(struct fuse_conn *fc) 
static void request_end(struct fuse_conn *fc, struct fuse_req *req)

{

	struct fuse_iqueue *fiq = &fc->iq;

	bool async = req->args->end;



	if (test_and_set_bit(FR_FINISHED, &req->flags))

		goto put_request;
@@ -302,8 +304,8 @@ static void request_end(struct fuse_conn *fc, struct fuse_req *req) 
		wake_up(&req->waitq);

	}



	if (req->end)

		req->end(fc, req);

	if (async)

		req->args->end(fc, req->args, req->out.h.error);

put_request:

	fuse_put_request(fc, req);

}
@@ -450,25 +452,12 @@ void fuse_args_to_req(struct fuse_req *req, struct fuse_args *args) 


	req->in.h.opcode = args->opcode;

	req->in.h.nodeid = args->nodeid;

	req->in.numargs = args->in_numargs;

	memcpy(req->in.args, args->in_args,

	       args->in_numargs * sizeof(struct fuse_in_arg));

	req->out.argvar = args->out_argvar;

	req->out.numargs = args->out_numargs;

	memcpy(req->out.args, args->out_args,

	       args->out_numargs * sizeof(struct fuse_arg));



	if (args->in_pages || args->out_pages) {

		req->in.argpages = args->in_pages;

		req->out.argpages = args->out_pages;

		req->out.page_zeroing = args->page_zeroing;

		req->out.page_replace = args->page_replace;



		req->pages = ap->pages;

		req->page_descs = ap->descs;

		req->num_pages = ap->num_pages;

	}



	req->args = args;

}



ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args)
@@ -502,7 +491,7 @@ ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args) 
	ret = req->out.h.error;

	if (!ret && args->out_argvar) {

		BUG_ON(args->out_numargs == 0);

		ret = req->out.args[args->out_numargs - 1].size;

		ret = args->out_args[args->out_numargs - 1].size;

	}

	fuse_put_request(fc, req);
@@ -538,19 +527,6 @@ static bool fuse_request_queue_background(struct fuse_conn *fc, 
	return queued;

}



static void fuse_simple_end(struct fuse_conn *fc, struct fuse_req *req)

{

	struct fuse_args *args = req->args;

	int err = req->out.h.error;



	if (!err && args->out_argvar) {

		BUG_ON(args->out_numargs == 0);

		args->out_args[args->out_numargs - 1].size =

			req->out.args[args->out_numargs - 1].size;

	}

	req->args->end(fc, req->args, req->out.h.error);

}



int fuse_simple_background(struct fuse_conn *fc, struct fuse_args *args,

			    gfp_t gfp_flags)

{
@@ -571,9 +547,6 @@ int fuse_simple_background(struct fuse_conn *fc, struct fuse_args *args, 


	fuse_args_to_req(req, args);



	req->args = args;

	req->end = fuse_simple_end;



	if (!fuse_request_queue_background(fc, req)) {

		fuse_put_request(fc, req);

		return -ENOTCONN;
@@ -598,8 +571,6 @@ static int fuse_simple_notify_reply(struct fuse_conn *fc, 
	req->in.h.unique = unique;



	fuse_args_to_req(req, args);

	req->args = args;

	req->end = fuse_simple_end;



	spin_lock(&fiq->lock);

	if (fiq->connected) {
@@ -1197,7 +1168,7 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file, 
	struct fuse_iqueue *fiq = &fc->iq;

	struct fuse_pqueue *fpq = &fud->pq;

	struct fuse_req *req;

	struct fuse_in *in;

	struct fuse_args *args;

	unsigned reqsize;

	unsigned int hash;
@@ -1258,14 +1229,14 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file, 
	list_del_init(&req->list);

	spin_unlock(&fiq->lock);



	in = &req->in;

	reqsize = in->h.len;

	args = req->args;

	reqsize = req->in.h.len;



	/* If request is too large, reply with an error and restart the read */

	if (nbytes < reqsize) {

		req->out.h.error = -EIO;

		/* SETXATTR is special, since it may contain too large data */

		if (in->h.opcode == FUSE_SETXATTR)

		if (args->opcode == FUSE_SETXATTR)

			req->out.h.error = -E2BIG;

		request_end(fc, req);

		goto restart;
@@ -1274,10 +1245,10 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file, 
	list_add(&req->list, &fpq->io);

	spin_unlock(&fpq->lock);

	cs->req = req;

	err = fuse_copy_one(cs, &in->h, sizeof(in->h));

	err = fuse_copy_one(cs, &req->in.h, sizeof(req->in.h));

	if (!err)

		err = fuse_copy_args(cs, in->numargs, in->argpages,

				     (struct fuse_arg *) in->args, 0);

		err = fuse_copy_args(cs, args->in_numargs, args->in_pages,

				     (struct fuse_arg *) args->in_args, 0);

	fuse_copy_finish(cs);

	spin_lock(&fpq->lock);

	clear_bit(FR_LOCKED, &req->flags);
@@ -1808,27 +1779,25 @@ static struct fuse_req *request_find(struct fuse_pqueue *fpq, u64 unique) 
	return NULL;

}



static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,

static int copy_out_args(struct fuse_copy_state *cs, struct fuse_args *args,

			 unsigned nbytes)

{

	unsigned reqsize = sizeof(struct fuse_out_header);



	if (out->h.error)

		return nbytes != reqsize ? -EINVAL : 0;



	reqsize += len_args(out->numargs, out->args);

	reqsize += len_args(args->out_numargs, args->out_args);



	if (reqsize < nbytes || (reqsize > nbytes && !out->argvar))

	if (reqsize < nbytes || (reqsize > nbytes && !args->out_argvar))

		return -EINVAL;

	else if (reqsize > nbytes) {

		struct fuse_arg *lastarg = &out->args[out->numargs-1];

		struct fuse_arg *lastarg = &args->out_args[args->out_numargs-1];

		unsigned diffsize = reqsize - nbytes;



		if (diffsize > lastarg->size)

			return -EINVAL;

		lastarg->size -= diffsize;

	}

	return fuse_copy_args(cs, out->numargs, out->argpages, out->args,

			      out->page_zeroing);

	return fuse_copy_args(cs, args->out_numargs, args->out_pages,

			      args->out_args, args->page_zeroing);

}



/*
@@ -1907,10 +1876,13 @@ static ssize_t fuse_dev_do_write(struct fuse_dev *fud, 
	set_bit(FR_LOCKED, &req->flags);

	spin_unlock(&fpq->lock);

	cs->req = req;

	if (!req->out.page_replace)

	if (!req->args->page_replace)

		cs->move_pages = 0;



	err = copy_out_args(cs, &req->out, nbytes);

	if (oh.error)

		err = nbytes != sizeof(oh) ? -EINVAL : 0;

	else

		err = copy_out_args(cs, req->args, nbytes);

	fuse_copy_finish(cs);



	spin_lock(&fpq->lock);

fs/fuse/fuse_i.h

+8 −52
Original line number Diff line number Diff line
@@ -224,57 +224,12 @@ struct fuse_in_arg { 
	const void *value;

};



/** The request input */

struct fuse_in {

	/** The request header */

	struct fuse_in_header h;



	/** True if the data for the last argument is in req->pages */

	unsigned argpages:1;



	/** Number of arguments */

	unsigned numargs;



	/** Array of arguments */

	struct fuse_in_arg args[3];

};



/** One output argument of a request */

struct fuse_arg {

	unsigned size;

	void *value;

};



/** The request output */

struct fuse_out {

	/** Header returned from userspace */

	struct fuse_out_header h;



	/*

	 * The following bitfields are not changed during the request

	 * processing

	 */



	/** Last argument is variable length (can be shorter than

	    arg->size) */

	unsigned argvar:1;



	/** Last argument is a list of pages to copy data to */

	unsigned argpages:1;



	/** Zero partially or not copied pages */

	unsigned page_zeroing:1;



	/** Pages may be replaced with new ones */

	unsigned page_replace:1;



	/** Number or arguments */

	unsigned numargs;



	/** Array of arguments */

	struct fuse_arg args[2];

};



/** FUSE page descriptor */

struct fuse_page_desc {

	unsigned int length;
@@ -385,11 +340,15 @@ struct fuse_req { 
	/* Request flags, updated with test/set/clear_bit() */

	unsigned long flags;



	/** The request input */

	struct fuse_in in;

	/* The request input header */

	struct {

		struct fuse_in_header h;

	} in;



	/** The request output */

	struct fuse_out out;

	/* The request output header */

	struct {

		struct fuse_out_header h;

	} out;



	/** Used to wake up the task waiting for completion of request*/

	wait_queue_head_t waitq;
@@ -403,9 +362,6 @@ struct fuse_req { 
	/** number of pages in vector */

	unsigned num_pages;



	/** Request completion callback */

	void (*end)(struct fuse_conn *, struct fuse_req *);



};



struct fuse_iqueue {