LU-11213 dne: add new dir hash type "space"

[fs/lustre-release.git] / lustre / include / uapi / linux / lustre / lustre_user.h

diff --git a/lustre/include/uapi/linux/lustre/lustre_user.h b/lustre/include/uapi/linux/lustre/lustre_user.h
index 0edb929..9ead0fc 100644 (file)
--- a/lustre/include/uapi/linux/lustre/lustre_user.h
+++ b/lustre/include/uapi/linux/lustre/lustre_user.h
@@ -804,11 +804,16 @@ enum lmv_hash_type {
        LMV_HASH_TYPE_UNKNOWN   = 0,    /* 0 is reserved for testing purpose */
        LMV_HASH_TYPE_ALL_CHARS = 1,
        LMV_HASH_TYPE_FNV_1A_64 = 2,
+       LMV_HASH_TYPE_SPACE     = 3,    /*
+                                        * distribute subdirs among all MDTs
+                                        * with balanced space usage.
+                                        */
        LMV_HASH_TYPE_MAX,
 };
 
 #define LMV_HASH_NAME_ALL_CHARS        "all_char"
 #define LMV_HASH_NAME_FNV_1A_64        "fnv_1a_64"
+#define LMV_HASH_NAME_SPACE    "space"
 
 extern char *mdt_hash_name[LMV_HASH_TYPE_MAX];
 
@@ -838,7 +843,7 @@ struct lmv_user_md_v1 {
        __u32   lum_stripe_count;  /* dirstripe count */
        __u32   lum_stripe_offset; /* MDT idx for default dirstripe */
        __u32   lum_hash_type;     /* Dir stripe policy */
-       __u32   lum_type;         /* LMV type: default or normal */
+       __u32   lum_type;         /* LMV type: default */
        __u32   lum_padding1;
        __u32   lum_padding2;
        __u32   lum_padding3;
@@ -856,6 +861,15 @@ static inline __u32 lmv_foreign_to_md_stripes(__u32 size)
               sizeof(struct lmv_user_mds_data);
 }
 
+/*
+ * NB, historically default layout didn't set type, but use XATTR name to differ
+ * from normal layout, for backward compatibility, define LMV_TYPE_DEFAULT 0x0,
+ * and still use the same method.
+ */
+enum lmv_type {
+       LMV_TYPE_DEFAULT = 0x0000,
+};
+
 static inline int lmv_user_md_size(int stripes, int lmm_magic)
 {
        int size = sizeof(struct lmv_user_md);