Commit f8dbdf81 authored by Maxim Patlasov's avatar Maxim Patlasov Committed by Miklos Szeredi
Browse files

fuse: rework fuse_readpages() 



The patch uses 'nr_pages' argument of fuse_readpages() as heuristics for the
number of page pointers to allocate.

This can be improved further by taking in consideration fc->max_read and gaps
between page indices, but it's not clear whether it's worthy or not.

Signed-off-by: default avatarMaxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
parent 4d53dc99

fs/fuse/file.c

+14 −2
Original line number Diff line number Diff line
@@ -641,6 +641,7 @@ struct fuse_fill_data { 
	struct fuse_req *req;

	struct file *file;

	struct inode *inode;

	unsigned nr_pages;

};



static int fuse_readpages_fill(void *_data, struct page *page)
@@ -656,16 +657,25 @@ static int fuse_readpages_fill(void *_data, struct page *page) 
	    (req->num_pages == FUSE_MAX_PAGES_PER_REQ ||

	     (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||

	     req->pages[req->num_pages - 1]->index + 1 != page->index)) {

		int nr_alloc = min_t(unsigned, data->nr_pages,

				     FUSE_MAX_PAGES_PER_REQ);

		fuse_send_readpages(req, data->file);

		data->req = req = fuse_get_req(fc, FUSE_MAX_PAGES_PER_REQ);

		data->req = req = fuse_get_req(fc, nr_alloc);

		if (IS_ERR(req)) {

			unlock_page(page);

			return PTR_ERR(req);

		}

	}



	if (WARN_ON(req->num_pages >= req->max_pages)) {

		fuse_put_request(fc, req);

		return -EIO;

	}



	page_cache_get(page);

	req->pages[req->num_pages] = page;

	req->num_pages++;

	data->nr_pages--;

	return 0;

}
@@ -676,6 +686,7 @@ static int fuse_readpages(struct file *file, struct address_space *mapping, 
	struct fuse_conn *fc = get_fuse_conn(inode);

	struct fuse_fill_data data;

	int err;

	int nr_alloc = min_t(unsigned, nr_pages, FUSE_MAX_PAGES_PER_REQ);



	err = -EIO;

	if (is_bad_inode(inode))
@@ -683,7 +694,8 @@ static int fuse_readpages(struct file *file, struct address_space *mapping, 


	data.file = file;

	data.inode = inode;

	data.req = fuse_get_req(fc, FUSE_MAX_PAGES_PER_REQ);

	data.req = fuse_get_req(fc, nr_alloc);

	data.nr_pages = nr_pages;

	err = PTR_ERR(data.req);

	if (IS_ERR(data.req))

		goto out;

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