fsi: Add regmap and refactor sbefifo

Merge series from Eddie James <eajames@linux.ibm.com>:

The SBEFIFO hardware can now be attached over a new I2C endpoint interface
called the I2C Responder (I2CR). In order to use the existing SBEFIFO
driver, add a regmap driver for the FSI bus and an endpoint driver for the
I2CR. Then, refactor the SBEFIFO and OCC drivers to clean up and use the
new regmap driver or the I2CR interface.

This branch just has the regmap change so it can be shared with the FSI
code.

1 files changed, 13 insertions, 7 deletions

diff --git a/fs/netfs/buffered_read.c b/fs/netfs/buffered_read.c
index 0ce535852151..7679a68e8193 100644
--- a/fs/netfs/buffered_read.c
+++ b/fs/netfs/buffered_read.c
@@ -17,9 +17,9 @@ void netfs_rreq_unlock_folios(struct netfs_io_request *rreq)
 {
 	struct netfs_io_subrequest *subreq;
 	struct folio *folio;
-	unsigned int iopos, account = 0;
 	pgoff_t start_page = rreq->start / PAGE_SIZE;
 	pgoff_t last_page = ((rreq->start + rreq->len) / PAGE_SIZE) - 1;
+	size_t account = 0;
 	bool subreq_failed = false;
 
 	XA_STATE(xas, &rreq->mapping->i_pages, start_page);
@@ -39,18 +39,23 @@ void netfs_rreq_unlock_folios(struct netfs_io_request *rreq)
 	 */
 	subreq = list_first_entry(&rreq->subrequests,
 				  struct netfs_io_subrequest, rreq_link);
-	iopos = 0;
 	subreq_failed = (subreq->error < 0);
 
 	trace_netfs_rreq(rreq, netfs_rreq_trace_unlock);
 
 	rcu_read_lock();
 	xas_for_each(&xas, folio, last_page) {
-		unsigned int pgpos = (folio_index(folio) - start_page) * PAGE_SIZE;
-		unsigned int pgend = pgpos + folio_size(folio);
+		loff_t pg_end;
 		bool pg_failed = false;
 
+		if (xas_retry(&xas, folio))
+			continue;
+
+		pg_end = folio_pos(folio) + folio_size(folio) - 1;
+
 		for (;;) {
+			loff_t sreq_end;
+
 			if (!subreq) {
 				pg_failed = true;
 				break;
@@ -58,11 +63,11 @@ void netfs_rreq_unlock_folios(struct netfs_io_request *rreq)
 			if (test_bit(NETFS_SREQ_COPY_TO_CACHE, &subreq->flags))
 				folio_start_fscache(folio);
 			pg_failed |= subreq_failed;
-			if (pgend < iopos + subreq->len)
+			sreq_end = subreq->start + subreq->len - 1;
+			if (pg_end < sreq_end)
 				break;
 
 			account += subreq->transferred;
-			iopos += subreq->len;
 			if (!list_is_last(&subreq->rreq_link, &rreq->subrequests)) {
 				subreq = list_next_entry(subreq, rreq_link);
 				subreq_failed = (subreq->error < 0);
@@ -70,7 +75,8 @@ void netfs_rreq_unlock_folios(struct netfs_io_request *rreq)
 				subreq = NULL;
 				subreq_failed = false;
 			}
-			if (pgend == iopos)
+
+			if (pg_end == sreq_end)
 				break;
 		}