* GPL HEADER END
*/
/*
- * Copyright (c) 2013, Intel Corporation.
+ * Copyright (c) 2014, 2016, Intel Corporation.
*/
/*
* lustre/include/lustre_lmv.h
#ifndef _LUSTRE_LMV_H
#define _LUSTRE_LMV_H
-#include <lustre/lustre_idl.h>
+#include <uapi/linux/lustre/lustre_idl.h>
struct lmv_oinfo {
struct lu_fid lmo_fid;
__u32 lsm_md_master_mdt_index;
__u32 lsm_md_hash_type;
__u32 lsm_md_layout_version;
+ __u32 lsm_md_migrate_offset;
+ __u32 lsm_md_migrate_hash;
__u32 lsm_md_default_count;
__u32 lsm_md_default_index;
char lsm_md_pool_name[LOV_MAXPOOLNAME + 1];
struct lmv_oinfo lsm_md_oinfo[0];
};
+static inline bool lmv_dir_striped(const struct lmv_stripe_md *lsm)
+{
+ return lsm && lsm->lsm_md_magic == LMV_MAGIC;
+}
+
+static inline bool lmv_dir_foreign(const struct lmv_stripe_md *lsm)
+{
+ return lsm && lsm->lsm_md_magic == LMV_MAGIC_FOREIGN;
+}
+
+static inline bool lmv_dir_migrating(const struct lmv_stripe_md *lsm)
+{
+ return lmv_dir_striped(lsm) &&
+ lsm->lsm_md_hash_type & LMV_HASH_FLAG_MIGRATION;
+}
+
+static inline bool lmv_dir_bad_hash(const struct lmv_stripe_md *lsm)
+{
+ if (!lmv_dir_striped(lsm))
+ return false;
+
+ if (lmv_dir_migrating(lsm) &&
+ lsm->lsm_md_stripe_count - lsm->lsm_md_migrate_offset <= 1)
+ return false;
+
+ if (lsm->lsm_md_hash_type & LMV_HASH_FLAG_BAD_TYPE)
+ return true;
+
+ return !lmv_is_known_hash_type(lsm->lsm_md_hash_type);
+}
+
static inline bool
lsm_md_eq(const struct lmv_stripe_md *lsm1, const struct lmv_stripe_md *lsm2)
{
lsm1->lsm_md_hash_type != lsm2->lsm_md_hash_type ||
lsm1->lsm_md_layout_version !=
lsm2->lsm_md_layout_version ||
- strcmp(lsm1->lsm_md_pool_name,
- lsm2->lsm_md_pool_name) != 0)
+ lsm1->lsm_md_migrate_offset !=
+ lsm2->lsm_md_migrate_offset ||
+ lsm1->lsm_md_migrate_hash !=
+ lsm2->lsm_md_migrate_hash ||
+ strncmp(lsm1->lsm_md_pool_name, lsm2->lsm_md_pool_name,
+ sizeof(lsm1->lsm_md_pool_name)) != 0)
return false;
- for (idx = 0; idx < lsm1->lsm_md_stripe_count; idx++) {
- if (!lu_fid_eq(&lsm1->lsm_md_oinfo[idx].lmo_fid,
- &lsm2->lsm_md_oinfo[idx].lmo_fid))
- return false;
+ if (lmv_dir_striped(lsm1)) {
+ for (idx = 0; idx < lsm1->lsm_md_stripe_count; idx++) {
+ if (!lu_fid_eq(&lsm1->lsm_md_oinfo[idx].lmo_fid,
+ &lsm2->lsm_md_oinfo[idx].lmo_fid))
+ return false;
+ }
}
return true;
}
+
+static inline void lsm_md_dump(int mask, const struct lmv_stripe_md *lsm)
+{
+ int i;
+
+ /* If lsm_md_magic == LMV_MAGIC_FOREIGN pool_name may not be a null
+ * terminated string so only print LOV_MAXPOOLNAME bytes.
+ */
+ CDEBUG(mask,
+ "magic %#x stripe count %d master mdt %d hash type %#x version %d migrate offset %d migrate hash %#x pool %.*s\n",
+ lsm->lsm_md_magic, lsm->lsm_md_stripe_count,
+ lsm->lsm_md_master_mdt_index, lsm->lsm_md_hash_type,
+ lsm->lsm_md_layout_version, lsm->lsm_md_migrate_offset,
+ lsm->lsm_md_migrate_hash,
+ LOV_MAXPOOLNAME, lsm->lsm_md_pool_name);
+
+ if (!lmv_dir_striped(lsm))
+ return;
+
+ for (i = 0; i < lsm->lsm_md_stripe_count; i++)
+ CDEBUG(mask, "stripe[%d] "DFID"\n",
+ i, PFID(&lsm->lsm_md_oinfo[i].lmo_fid));
+}
+
union lmv_mds_md;
-int lmv_pack_md(union lmv_mds_md **lmmp, const struct lmv_stripe_md *lsm,
- int stripe_count);
-int lmv_alloc_md(union lmv_mds_md **lmmp, int stripe_count);
-void lmv_free_md(union lmv_mds_md *lmm);
-int lmv_alloc_memmd(struct lmv_stripe_md **lsmp, int stripe_count);
void lmv_free_memmd(struct lmv_stripe_md *lsm);
-int lmvea_load_shards(const struct lu_env *env, struct dt_object *obj,
- struct lu_dirent *ent, struct lu_buf *buf,
- bool resize);
-
static inline void lmv1_le_to_cpu(struct lmv_mds_md_v1 *lmv_dst,
const struct lmv_mds_md_v1 *lmv_src)
{
}
}
+/* This hash is only for testing purpose */
+static inline unsigned int
+lmv_hash_all_chars(unsigned int count, const char *name, int namelen)
+{
+ unsigned int c = 0;
+ const unsigned char *p = (const unsigned char *)name;
+
+ while (--namelen >= 0)
+ c += p[namelen];
+
+ c = c % count;
+
+ return c;
+}
+
+static inline unsigned int
+lmv_hash_fnv1a(unsigned int count, const char *name, int namelen)
+{
+ __u64 hash;
+
+ hash = lustre_hash_fnv_1a_64(name, namelen);
+
+ return do_div(hash, count);
+}
+
+/*
+ * Robert Jenkins' function for mixing 32-bit values
+ * http://burtleburtle.net/bob/hash/evahash.html
+ * a, b = random bits, c = input and output
+ *
+ * Mixing inputs to generate an evenly distributed hash.
+ */
+#define crush_hashmix(a, b, c) \
+do { \
+ a = a - b; a = a - c; a = a ^ (c >> 13); \
+ b = b - c; b = b - a; b = b ^ (a << 8); \
+ c = c - a; c = c - b; c = c ^ (b >> 13); \
+ a = a - b; a = a - c; a = a ^ (c >> 12); \
+ b = b - c; b = b - a; b = b ^ (a << 16); \
+ c = c - a; c = c - b; c = c ^ (b >> 5); \
+ a = a - b; a = a - c; a = a ^ (c >> 3); \
+ b = b - c; b = b - a; b = b ^ (a << 10); \
+ c = c - a; c = c - b; c = c ^ (b >> 15); \
+} while (0)
+
+#define crush_hash_seed 1315423911
+
+static inline __u32 crush_hash(__u32 a, __u32 b)
+{
+ __u32 hash = crush_hash_seed ^ a ^ b;
+ __u32 x = 231232;
+ __u32 y = 1232;
+
+ crush_hashmix(a, b, hash);
+ crush_hashmix(x, a, hash);
+ crush_hashmix(b, y, hash);
+
+ return hash;
+}
+
+/* refer to https://github.com/ceph/ceph/blob/master/src/crush/hash.c and
+ * https://www.ssrc.ucsc.edu/Papers/weil-sc06.pdf for details of CRUSH
+ * algorithm.
+ */
+static inline unsigned int
+lmv_hash_crush(unsigned int count, const char *name, int namelen)
+{
+ unsigned long long straw;
+ unsigned long long highest_straw = 0;
+ unsigned int pg_id;
+ unsigned int idx = 0;
+ int i;
+
+ /* put temp and backup file on the same MDT where target is located.
+ * temporary file naming rule:
+ * 1. rsync: .<target>.XXXXXX
+ * 2. dstripe: <target>.XXXXXXXX
+ */
+ if (lu_name_is_temp_file(name, namelen, true, 6)) {
+ name++;
+ namelen -= 8;
+ } else if (lu_name_is_temp_file(name, namelen, false, 8)) {
+ namelen -= 9;
+ } else if (lu_name_is_backup_file(name, namelen, &i)) {
+ LASSERT(i < namelen);
+ namelen -= i;
+ }
+
+ pg_id = lmv_hash_fnv1a(LMV_CRUSH_PG_COUNT, name, namelen);
+
+ /* distribute PG among all stripes pseudo-randomly, so they are almost
+ * evenly distributed, and when stripe count changes, only (delta /
+ * total) sub files need to be moved, herein 'delta' is added or removed
+ * stripe count, 'total' is total stripe count before change for
+ * removal, or count after change for addition.
+ */
+ for (i = 0; i < count; i++) {
+ straw = crush_hash(pg_id, i);
+ if (straw > highest_straw) {
+ highest_straw = straw;
+ idx = i;
+ }
+ }
+ LASSERT(idx < count);
+
+ return idx;
+}
+
+static inline int lmv_name_to_stripe_index(__u32 hash_type,
+ unsigned int stripe_count,
+ const char *name, int namelen)
+{
+ unsigned int idx;
+
+ LASSERT(namelen > 0);
+ LASSERT(stripe_count > 0);
+
+ if (stripe_count == 1)
+ return 0;
+
+ switch (hash_type & LMV_HASH_TYPE_MASK) {
+ case LMV_HASH_TYPE_ALL_CHARS:
+ idx = lmv_hash_all_chars(stripe_count, name, namelen);
+ break;
+ case LMV_HASH_TYPE_FNV_1A_64:
+ idx = lmv_hash_fnv1a(stripe_count, name, namelen);
+ break;
+ case LMV_HASH_TYPE_CRUSH:
+ idx = lmv_hash_crush(stripe_count, name, namelen);
+ break;
+ default:
+ return -EBADFD;
+ }
+
+ CDEBUG(D_INFO, "name %.*s hash_type %#x idx %d/%u\n", namelen, name,
+ hash_type, idx, stripe_count);
+
+ return idx;
+}
+
+static inline bool lmv_user_magic_supported(__u32 lum_magic)
+{
+ return lum_magic == LMV_USER_MAGIC ||
+ lum_magic == LMV_USER_MAGIC_SPECIFIC ||
+ lum_magic == LMV_MAGIC_FOREIGN;
+}
+
+static inline bool lmv_is_sane(const struct lmv_mds_md_v1 *lmv)
+{
+ if (le32_to_cpu(lmv->lmv_magic) != LMV_MAGIC_V1)
+ return false;
+
+ if (le32_to_cpu(lmv->lmv_stripe_count) == 0)
+ return false;
+
+ if (!lmv_is_known_hash_type(lmv->lmv_hash_type))
+ return false;
+
+ return true;
+}
+
#endif