Commit 7f024647 authored by Al Viro's avatar Al Viro
Browse files

9p: convert to advancing variant of iov_iter_get_pages_alloc() 



that one is somewhat clumsier than usual and needs serious testing.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent dc5801f6

net/9p/client.c

+23 −16
Original line number Diff line number Diff line
@@ -1491,7 +1491,7 @@ p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, 
	struct p9_client *clnt = fid->clnt;

	struct p9_req_t *req;

	int count = iov_iter_count(to);

	int rsize, non_zc = 0;

	int rsize, received, non_zc = 0;

	char *dataptr;



	*err = 0;
@@ -1520,36 +1520,40 @@ p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, 
	}

	if (IS_ERR(req)) {

		*err = PTR_ERR(req);

		if (!non_zc)

			iov_iter_revert(to, count - iov_iter_count(to));

		return 0;

	}



	*err = p9pdu_readf(&req->rc, clnt->proto_version,

			   "D", &count, &dataptr);

			   "D", &received, &dataptr);

	if (*err) {

		if (!non_zc)

			iov_iter_revert(to, count - iov_iter_count(to));

		trace_9p_protocol_dump(clnt, &req->rc);

		p9_tag_remove(clnt, req);

		return 0;

	}

	if (rsize < count) {

		pr_err("bogus RREAD count (%d > %d)\n", count, rsize);

		count = rsize;

	if (rsize < received) {

		pr_err("bogus RREAD count (%d > %d)\n", received, rsize);

		received = rsize;

	}



	p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);



	if (non_zc) {

		int n = copy_to_iter(dataptr, count, to);

		int n = copy_to_iter(dataptr, received, to);



		if (n != count) {

		if (n != received) {

			*err = -EFAULT;

			p9_tag_remove(clnt, req);

			return n;

		}

	} else {

		iov_iter_advance(to, count);

		iov_iter_revert(to, count - received - iov_iter_count(to));

	}

	p9_tag_remove(clnt, req);

	return count;

	return received;

}

EXPORT_SYMBOL(p9_client_read_once);
@@ -1567,6 +1571,7 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) 
	while (iov_iter_count(from)) {

		int count = iov_iter_count(from);

		int rsize = fid->iounit;

		int written;



		if (!rsize || rsize > clnt->msize - P9_IOHDRSZ)

			rsize = clnt->msize - P9_IOHDRSZ;
@@ -1584,27 +1589,29 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) 
					    offset, rsize, from);

		}

		if (IS_ERR(req)) {

			iov_iter_revert(from, count - iov_iter_count(from));

			*err = PTR_ERR(req);

			break;

		}



		*err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &count);

		*err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &written);

		if (*err) {

			iov_iter_revert(from, count - iov_iter_count(from));

			trace_9p_protocol_dump(clnt, &req->rc);

			p9_tag_remove(clnt, req);

			break;

		}

		if (rsize < count) {

			pr_err("bogus RWRITE count (%d > %d)\n", count, rsize);

			count = rsize;

		if (rsize < written) {

			pr_err("bogus RWRITE count (%d > %d)\n", written, rsize);

			written = rsize;

		}



		p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);



		p9_tag_remove(clnt, req);

		iov_iter_advance(from, count);

		total += count;

		offset += count;

		iov_iter_revert(from, count - written - iov_iter_count(from));

		total += written;

		offset += written;

	}

	return total;

}

net/9p/protocol.c

+1 −2
Original line number Diff line number Diff line
@@ -63,9 +63,8 @@ static size_t 
pdu_write_u(struct p9_fcall *pdu, struct iov_iter *from, size_t size)

{

	size_t len = min(pdu->capacity - pdu->size, size);

	struct iov_iter i = *from;



	if (!copy_from_iter_full(&pdu->sdata[pdu->size], len, &i))

	if (!copy_from_iter_full(&pdu->sdata[pdu->size], len, from))

		len = 0;



	pdu->size += len;

net/9p/trans_virtio.c

+2 −1
Original line number Diff line number Diff line
@@ -331,7 +331,7 @@ static int p9_get_mapped_pages(struct virtio_chan *chan, 
			if (err == -ERESTARTSYS)

				return err;

		}

		n = iov_iter_get_pages_alloc(data, pages, count, offs);

		n = iov_iter_get_pages_alloc2(data, pages, count, offs);

		if (n < 0)

			return n;

		*need_drop = 1;
@@ -373,6 +373,7 @@ static int p9_get_mapped_pages(struct virtio_chan *chan, 
				(*pages)[index] = kmap_to_page(p);

			p += PAGE_SIZE;

		}

		iov_iter_advance(data, len);

		return len;

	}

}