1 // SPDX-License-Identifier: GPL-2.0-or-later
21 	struct netfs_io_request *rreq = subreq->rreq;  in netfs_prepare_dio_read_iterator()
24 	rsize = umin(subreq->len, rreq->io_streams[0].sreq_max_len);  in netfs_prepare_dio_read_iterator()
25 	subreq->len = rsize;  in netfs_prepare_dio_read_iterator()
27 	if (unlikely(rreq->io_streams[0].sreq_max_segs)) {  in netfs_prepare_dio_read_iterator()
28 		size_t limit = netfs_limit_iter(&rreq->buffer.iter, 0, rsize,  in netfs_prepare_dio_read_iterator()
29 						rreq->io_streams[0].sreq_max_segs);  in netfs_prepare_dio_read_iterator()
32 			subreq->len = limit;  in netfs_prepare_dio_read_iterator()
39 	subreq->io_iter	= rreq->buffer.iter;  in netfs_prepare_dio_read_iterator()
40 	iov_iter_truncate(&subreq->io_iter, subreq->len);  in netfs_prepare_dio_read_iterator()
41 	iov_iter_advance(&rreq->buffer.iter, subreq->len);  in netfs_prepare_dio_read_iterator()
50 	struct netfs_io_stream *stream = &rreq->io_streams[0];  in netfs_dispatch_unbuffered_reads()
51 	unsigned long long start = rreq->start;  in netfs_dispatch_unbuffered_reads()
52 	ssize_t size = rreq->len;  in netfs_dispatch_unbuffered_reads()
61 			ret = -ENOMEM;  in netfs_dispatch_unbuffered_reads()
65 		subreq->source	= NETFS_DOWNLOAD_FROM_SERVER;  in netfs_dispatch_unbuffered_reads()
66 		subreq->start	= start;  in netfs_dispatch_unbuffered_reads()
67 		subreq->len	= size;  in netfs_dispatch_unbuffered_reads()
69 		__set_bit(NETFS_SREQ_IN_PROGRESS, &subreq->flags);  in netfs_dispatch_unbuffered_reads()
71 		spin_lock(&rreq->lock);  in netfs_dispatch_unbuffered_reads()
72 		list_add_tail(&subreq->rreq_link, &stream->subrequests);  in netfs_dispatch_unbuffered_reads()
73 		if (list_is_first(&subreq->rreq_link, &stream->subrequests)) {  in netfs_dispatch_unbuffered_reads()
74 			stream->front = subreq;  in netfs_dispatch_unbuffered_reads()
75 			if (!stream->active) {  in netfs_dispatch_unbuffered_reads()
76 				stream->collected_to = stream->front->start;  in netfs_dispatch_unbuffered_reads()
77 				/* Store list pointers before active flag */  in netfs_dispatch_unbuffered_reads()
78 				smp_store_release(&stream->active, true);  in netfs_dispatch_unbuffered_reads()
82 		spin_unlock(&rreq->lock);  in netfs_dispatch_unbuffered_reads()
85 		if (rreq->netfs_ops->prepare_read) {  in netfs_dispatch_unbuffered_reads()
86 			ret = rreq->netfs_ops->prepare_read(subreq);  in netfs_dispatch_unbuffered_reads()
94 		slice = subreq->len;  in netfs_dispatch_unbuffered_reads()
95 		size -= slice;  in netfs_dispatch_unbuffered_reads()
97 		rreq->submitted += slice;  in netfs_dispatch_unbuffered_reads()
100 			set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags);  in netfs_dispatch_unbuffered_reads()
103 		rreq->netfs_ops->issue_read(subreq);  in netfs_dispatch_unbuffered_reads()
105 		if (test_bit(NETFS_RREQ_PAUSE, &rreq->flags))  in netfs_dispatch_unbuffered_reads()
107 		if (test_bit(NETFS_RREQ_FAILED, &rreq->flags))  in netfs_dispatch_unbuffered_reads()
109 		if (test_bit(NETFS_RREQ_BLOCKED, &rreq->flags) &&  in netfs_dispatch_unbuffered_reads()
110 		    test_bit(NETFS_RREQ_NONBLOCK, &rreq->flags))  in netfs_dispatch_unbuffered_reads()
117 		set_bit(NETFS_RREQ_ALL_QUEUED, &rreq->flags);  in netfs_dispatch_unbuffered_reads()
128 static int netfs_unbuffered_read(struct netfs_io_request *rreq, bool sync)  in netfs_unbuffered_read()  argument
132 	_enter("R=%x %llx-%llx",  in netfs_unbuffered_read()
133 	       rreq->debug_id, rreq->start, rreq->start + rreq->len - 1);  in netfs_unbuffered_read()
135 	if (rreq->len == 0) {  in netfs_unbuffered_read()
136 		pr_err("Zero-sized read [R=%x]\n", rreq->debug_id);  in netfs_unbuffered_read()
137 		return -EIO;  in netfs_unbuffered_read()
142 	inode_dio_begin(rreq->inode);  in netfs_unbuffered_read()
146 	if (!rreq->submitted) {  in netfs_unbuffered_read()
148 		inode_dio_end(rreq->inode);  in netfs_unbuffered_read()
153 	if (sync)  in netfs_unbuffered_read()
156 		ret = -EIOCBQUEUED;  in netfs_unbuffered_read()
163  * netfs_unbuffered_read_iter_locked - Perform an unbuffered or direct I/O read
177 	bool sync = is_sync_kiocb(iocb);  in netfs_unbuffered_read_iter_locked()  local
187 	file_accessed(iocb->ki_filp);  in netfs_unbuffered_read_iter_locked()
189 	rreq = netfs_alloc_request(iocb->ki_filp->f_mapping, iocb->ki_filp,  in netfs_unbuffered_read_iter_locked()
190 				   iocb->ki_pos, orig_count,  in netfs_unbuffered_read_iter_locked()
196 	trace_netfs_read(rreq, rreq->start, rreq->len, netfs_read_trace_dio_read);  in netfs_unbuffered_read_iter_locked()
208 		ret = netfs_extract_user_iter(iter, rreq->len, &rreq->buffer.iter, 0);  in netfs_unbuffered_read_iter_locked()
211 		rreq->direct_bv = (struct bio_vec *)rreq->buffer.iter.bvec;  in netfs_unbuffered_read_iter_locked()
212 		rreq->direct_bv_count = ret;  in netfs_unbuffered_read_iter_locked()
213 		rreq->direct_bv_unpin = iov_iter_extract_will_pin(iter);  in netfs_unbuffered_read_iter_locked()
214 		rreq->len = iov_iter_count(&rreq->buffer.iter);  in netfs_unbuffered_read_iter_locked()
216 		rreq->buffer.iter = *iter;  in netfs_unbuffered_read_iter_locked()
217 		rreq->len = orig_count;  in netfs_unbuffered_read_iter_locked()
218 		rreq->direct_bv_unpin = false;  in netfs_unbuffered_read_iter_locked()
224 	if (!sync) {  in netfs_unbuffered_read_iter_locked()
225 		rreq->iocb = iocb;  in netfs_unbuffered_read_iter_locked()
226 		__set_bit(NETFS_RREQ_OFFLOAD_COLLECTION, &rreq->flags);  in netfs_unbuffered_read_iter_locked()
229 	ret = netfs_unbuffered_read(rreq, sync);  in netfs_unbuffered_read_iter_locked()
231 		goto out; /* May be -EIOCBQUEUED */  in netfs_unbuffered_read_iter_locked()
232 	if (sync) {  in netfs_unbuffered_read_iter_locked()
234 		iocb->ki_pos += rreq->transferred;  in netfs_unbuffered_read_iter_locked()
235 		ret = rreq->transferred;  in netfs_unbuffered_read_iter_locked()
241 		orig_count -= ret;  in netfs_unbuffered_read_iter_locked()
247  * netfs_unbuffered_read_iter - Perform an unbuffered or direct I/O read
256 	struct inode *inode = file_inode(iocb->ki_filp);  in netfs_unbuffered_read_iter()
259 	if (!iter->count)  in netfs_unbuffered_read_iter()