Fixup for prefetching support on macOS

The new code path (commit 6654bb92047) should call FileAccess() first,
like the posix_fadvise() path.

Reported-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/0827edec-1317-4917-a186-035eb1e3241d%40eisentraut.org

diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index c84f089665c92229b06e03459d9c76622bcd063a..368cc9455cf7612fefe5ef03bde416f984776ec0 100644 (file)
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -2110,6 +2110,10 @@ retry:
                }                       ra;
                int                     returnCode;
 
+               returnCode = FileAccess(file);
+               if (returnCode < 0)
+                       return returnCode;
+
                ra.ra_offset = offset;
                ra.ra_count = amount;
                pgstat_report_wait_start(wait_event_info);