If it is present, use it; otherwise use 4096. Also provide a new macro
to let user have control over the page size used to do calculation.
Signed-off-by: Wei Liu <wei.l...@citrix.com>
---
Cc: Andrew Cooper <andrew.coop...@citrix.com>
Cc: George Dunlap <george.dun...@eu.citrix.com>
Cc: Ian Jackson <ian.jack...@eu.citrix.com>
Cc: Jan Beulich <jbeul...@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.w...@oracle.com>
Cc: Stefano Stabellini <sstabell...@kernel.org>
Cc: Tim Deegan <t...@xen.org>
Cc: Wei Liu <wei.l...@citrix.com>
Cc: Juergen Gross <jgr...@suse.com>
---
xen/include/public/io/vscsiif.h | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
diff --git a/xen/include/public/io/vscsiif.h b/xen/include/public/io/vscsiif.h
index 0a4709f..00e8b74 100644
--- a/xen/include/public/io/vscsiif.h
+++ b/xen/include/public/io/vscsiif.h
@@ -256,7 +256,23 @@ struct scsiif_request_segment {
};
typedef struct scsiif_request_segment vscsiif_segment_t;
-#define VSCSIIF_SG_PER_PAGE (PAGE_SIZE / sizeof(struct scsiif_request_segment))
+/*
+ * Reference to PAGE_SIZE was overlooked when this header file was
+ * introduced. Respect PAGE_SIZE if defined, otherwise, use 4096.
+ */
+#ifdef PAGE_SIZE
+#define _VSCSIIF_PAGE_SIZE PAGE_SIZE
+#else
+#define _VSCSIIF_PAGE_SIZE 4096
+#endif
+/*
+ * Please use _PAGE2 variant in new code, _PAGE variant is kept for
+ * backward-compatibility.
+ */
+#define VSCSIIF_SG_PER_PAGE (_VSCSI_PAGE_SIZE / \
+ sizeof(struct scsiif_request_segment))
+#define VSCSIIF_SG_PER_PAGE2(pgsize) ((pgsize) / \
+ sizeof(struct scsiif_request_segment))
/* Size of one request is 252 bytes */
struct vscsiif_request {
--
2.1.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
