LU-12367 llite: Fix page count for unaligned reads

[fs/lustre-release.git] / lustre / llite / vvp_io.c

diff --git a/lustre/llite/vvp_io.c b/lustre/llite/vvp_io.c
index 2c0157f..ead8099 100644 (file)
--- a/lustre/llite/vvp_io.c
+++ b/lustre/llite/vvp_io.c
@@ -817,6 +817,13 @@ static int vvp_io_read_start(const struct lu_env *env,
                vio->vui_ra_valid = true;
                vio->vui_ra_start = cl_index(obj, pos);
                vio->vui_ra_count = cl_index(obj, tot + PAGE_SIZE - 1);
+               /* If both start and end are unaligned, we read one more page
+                * than the index math suggests. */
+               if (pos % PAGE_SIZE != 0 && (pos + tot) % PAGE_SIZE != 0)
+                       vio->vui_ra_count++;
+
+               CDEBUG(D_READA, "tot %ld, ra_start %lu, ra_count %lu\n", tot,
+                      vio->vui_ra_start, vio->vui_ra_count);
        }
 
        /* BUG: 5972 */