X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lustre%2Finclude%2Fobd_lov.h;h=9b853d06fe91c43fa4ec9d3c4748c4fe5325dd0f;hb=cbda7339018323d3469489a0d02bae785297dd2d;hp=64798ab3f682370a93c6f12397b29b288b457231;hpb=6869932b552ac705f411de3362f01bd50c1f6f7d;p=fs%2Flustre-release.git

diff --git a/lustre/include/obd_lov.h b/lustre/include/obd_lov.h
index 64798ab..9b853d0 100644
--- a/lustre/include/obd_lov.h
+++ b/lustre/include/obd_lov.h
@@ -1,6 +1,4 @@
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -26,8 +24,10 @@
  * GPL HEADER END
  */
 /*
- * Copyright  2008 Sun Microsystems, Inc. All rights reserved
+ * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
+ *
+ * Copyright (c) 2012, Whamcloud, Inc.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -37,18 +37,82 @@
 #ifndef _OBD_LOV_H__
 #define _OBD_LOV_H__
 
-static inline int lov_stripe_md_size(int stripes)
+static inline int lov_stripe_md_size(__u16 stripes)
 {
         return sizeof(struct lov_stripe_md) + stripes*sizeof(struct lov_oinfo*);
 }
 
-#define lov_mds_md_size(stripes) lov_mds_md_v1_size(stripes)
-static inline int lov_mds_md_v1_size(int stripes)
+static inline __u32 lov_mds_md_size(__u16 stripes, __u32 lmm_magic)
 {
-        return sizeof(struct lov_mds_md_v1) +
-                stripes * sizeof(struct lov_ost_data_v1);
+        if (lmm_magic == LOV_MAGIC_V3)
+                return sizeof(struct lov_mds_md_v3) +
+                        stripes * sizeof(struct lov_ost_data_v1);
+        else
+                return sizeof(struct lov_mds_md_v1) +
+                        stripes * sizeof(struct lov_ost_data_v1);
 }
 
+struct lov_version_size {
+        __u32   lvs_magic;
+        size_t  lvs_lmm_size;
+        size_t  lvs_lod_size;
+};
+
+static inline __u32 lov_mds_md_stripecnt(int ea_size, __u32 lmm_magic)
+{
+        static const struct lov_version_size lmm_ver_size[] = {
+                        { .lvs_magic = LOV_MAGIC_V3,
+                          .lvs_lmm_size = sizeof(struct lov_mds_md_v3),
+                          .lvs_lod_size = sizeof(struct lov_ost_data_v1) },
+                        { .lvs_magic = LOV_MAGIC_V1,
+                          .lvs_lmm_size = sizeof(struct lov_mds_md_v1),
+                          .lvs_lod_size = sizeof(struct lov_ost_data_v1)} };
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(lmm_ver_size); i++) {
+                if (lmm_magic == lmm_ver_size[i].lvs_magic) {
+                        if (ea_size <= lmm_ver_size[i].lvs_lmm_size)
+                                return 0;
+                        return (ea_size - lmm_ver_size[i].lvs_lmm_size) /
+                                lmm_ver_size[i].lvs_lod_size;
+                }
+        }
+
+        /* Invalid LOV magic, so no stripes could fit */
+        return 0;
+}
+
+/* lov_do_div64(a, b) returns a % b, and a = a / b.
+ * The 32-bit code is LOV-specific due to knowing about stripe limits in
+ * order to reduce the divisor to a 32-bit number.  If the divisor is
+ * already a 32-bit value the compiler handles this directly. */
+#if BITS_PER_LONG > 32
+# define lov_do_div64(n,base) ({					\
+	uint64_t __base = (base);					\
+	uint64_t __rem;							\
+	__rem = ((uint64_t)(n)) % __base;				\
+	(n) = ((uint64_t)(n)) / __base;					\
+	__rem;								\
+  })
+#else
+# define lov_do_div64(n,base) ({					\
+	uint64_t __rem;							\
+	if ((sizeof(base) > 4) && (((base) & 0xffffffff00000000ULL) != 0)) {  \
+		int __remainder;					      \
+		LASSERTF(!((base) & (LOV_MIN_STRIPE_SIZE - 1)), "64 bit lov " \
+			 "division %llu / %llu\n", (n), (uint64_t)(base));    \
+		__remainder = (n) & (LOV_MIN_STRIPE_SIZE - 1);		\
+		(n) >>= LOV_MIN_STRIPE_BITS;				\
+		__rem = do_div(n, (base) >> LOV_MIN_STRIPE_BITS);	\
+		__rem <<= LOV_MIN_STRIPE_BITS;				\
+		__rem += __remainder;					\
+	} else {							\
+		__rem = do_div(n, base);				\
+	}								\
+	__rem;								\
+  })
+#endif
+
 #define IOC_LOV_TYPE                   'g'
 #define IOC_LOV_MIN_NR                 50
 #define IOC_LOV_SET_OSC_ACTIVE         _IOWR('g', 50, long)