Commit d07f09f5 authored by Maxim Patlasov's avatar Maxim Patlasov Committed by Miklos Szeredi
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fuse: rework fuse_perform_write() 



The patch allocates as many page pointers in fuse_req as needed to cover
interval [pos .. pos+len-1]. Inline helper fuse_wr_pages() is introduced
to hide this cumbersome arithmetic.

Signed-off-by: default avatarMaxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
parent f8dbdf81

fs/fuse/file.c

+11 −2
Original line number Diff line number Diff line
@@ -881,11 +881,19 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req, 
		if (!fc->big_writes)

			break;

	} while (iov_iter_count(ii) && count < fc->max_write &&

		 req->num_pages < FUSE_MAX_PAGES_PER_REQ && offset == 0);

		 req->num_pages < req->max_pages && offset == 0);



	return count > 0 ? count : err;

}



static inline unsigned fuse_wr_pages(loff_t pos, size_t len)

{

	return min_t(unsigned,

		     ((pos + len - 1) >> PAGE_CACHE_SHIFT) -

		     (pos >> PAGE_CACHE_SHIFT) + 1,

		     FUSE_MAX_PAGES_PER_REQ);

}



static ssize_t fuse_perform_write(struct file *file,

				  struct address_space *mapping,

				  struct iov_iter *ii, loff_t pos)
@@ -901,8 +909,9 @@ static ssize_t fuse_perform_write(struct file *file, 
	do {

		struct fuse_req *req;

		ssize_t count;

		unsigned nr_pages = fuse_wr_pages(pos, iov_iter_count(ii));



		req = fuse_get_req(fc, FUSE_MAX_PAGES_PER_REQ);

		req = fuse_get_req(fc, nr_pages);

		if (IS_ERR(req)) {

			err = PTR_ERR(req);

			break;