[SCSI] st: Increase success probability in driver buffer allocation

Modify allocation to try the minimum possible page order allowed by the HBA scatter/gather segment limit in allocation of the driver's internal buffer. This increases the probability of successful allocation. The allocation may still fail if this minimum order is > 0. Signed-off-by: FUJITA Tomonori <[email protected]> Signed-off-by: Kai Makisara <[email protected]> Reported-by: Lukas Kolbe <[email protected]> Signed-off-by: James Bottomley <[email protected]>
kyagi · Dec 23, 2010 · 46081b1 · 46081b1
1 parent 373daac
commit 46081b1
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
@@ -3729,7 +3729,8 @@ static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dm
 		b_size = PAGE_SIZE << order;
 	} else {
 		for (b_size = PAGE_SIZE, order = 0;
-		     order < ST_MAX_ORDER && b_size < new_size;
+		     order < ST_MAX_ORDER &&
+			     max_segs * (PAGE_SIZE << order) < new_size;
 		     order++, b_size *= 2)
 			;  /* empty */
 		STbuffer->reserved_page_order = order;