[SCSI] st: retry enlarge_buffer allocation
Make enlarge_buffer() retry allocation if the previously chosen page
order was too small. Really limit the page order to 6. Return error if
the maximum order is not large enough for the request.
Signed-off-by: Kai Makisara <Kai.Makisara@kolumbus.fi>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index ddf2630..c6f19ee 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -3695,6 +3695,8 @@
/* Try to allocate enough space in the tape buffer */
+#define ST_MAX_ORDER 6
+
static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dma)
{
int segs, nbr, max_segs, b_size, order, got;
@@ -3723,9 +3725,16 @@
b_size = PAGE_SIZE << order;
} else {
for (b_size = PAGE_SIZE, order = 0;
- order <= 6 && b_size < new_size; order++, b_size *= 2)
+ order < ST_MAX_ORDER && b_size < new_size;
+ order++, b_size *= 2)
; /* empty */
}
+ if (max_segs * (PAGE_SIZE << order) < new_size) {
+ if (order == ST_MAX_ORDER)
+ return 0;
+ normalize_buffer(STbuffer);
+ return enlarge_buffer(STbuffer, new_size, need_dma);
+ }
for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
segs < max_segs && got < new_size;) {