1 files changed, 681 insertions, 0 deletions

diff --git a/drivers/staging/lustre/lustre/lov/lov_pool.c b/drivers/staging/lustre/lustre/lov/lov_pool.c
new file mode 100644
index 000000000000..a96f90880c64
--- /dev/null
+++ b/drivers/staging/lustre/lustre/lov/lov_pool.c
@@ -0,0 +1,681 @@
+/*
+ * GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see [sun.com URL with a
+ * copy of GPLv2].
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2012, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Sun Microsystems, Inc.
+ *
+ * lustre/lov/lov_pool.c
+ *
+ * OST pool methods
+ *
+ * Author: Jacques-Charles LAFOUCRIERE <jc.lafoucriere@cea.fr>
+ * Author: Alex Lyashkov <Alexey.Lyashkov@Sun.COM>
+ * Author: Nathaniel Rutman <Nathan.Rutman@Sun.COM>
+ */
+
+#define DEBUG_SUBSYSTEM S_LOV
+
+#include <linux/libcfs/libcfs.h>
+
+#include <obd.h>
+#include "lov_internal.h"
+
+#define pool_tgt(_p, _i) \
+		_p->pool_lobd->u.lov.lov_tgts[_p->pool_obds.op_array[_i]]
+
+static void lov_pool_getref(struct pool_desc *pool)
+{
+	CDEBUG(D_INFO, "pool %p\n", pool);
+	atomic_inc(&pool->pool_refcount);
+}
+
+void lov_pool_putref(struct pool_desc *pool)
+{
+	CDEBUG(D_INFO, "pool %p\n", pool);
+	if (atomic_dec_and_test(&pool->pool_refcount)) {
+		LASSERT(hlist_unhashed(&pool->pool_hash));
+		LASSERT(list_empty(&pool->pool_list));
+		LASSERT(pool->pool_proc_entry == NULL);
+		lov_ost_pool_free(&(pool->pool_rr.lqr_pool));
+		lov_ost_pool_free(&(pool->pool_obds));
+		OBD_FREE_PTR(pool);
+		EXIT;
+	}
+}
+
+void lov_pool_putref_locked(struct pool_desc *pool)
+{
+	CDEBUG(D_INFO, "pool %p\n", pool);
+	LASSERT(atomic_read(&pool->pool_refcount) > 1);
+
+	atomic_dec(&pool->pool_refcount);
+}
+
+/*
+ * hash function using a Rotating Hash algorithm
+ * Knuth, D. The Art of Computer Programming,
+ * Volume 3: Sorting and Searching,
+ * Chapter 6.4.
+ * Addison Wesley, 1973
+ */
+static __u32 pool_hashfn(cfs_hash_t *hash_body, const void *key, unsigned mask)
+{
+	int i;
+	__u32 result;
+	char *poolname;
+
+	result = 0;
+	poolname = (char *)key;
+	for (i = 0; i < LOV_MAXPOOLNAME; i++) {
+		if (poolname[i] == '\0')
+			break;
+		result = (result << 4)^(result >> 28) ^  poolname[i];
+	}
+	return (result % mask);
+}
+
+static void *pool_key(struct hlist_node *hnode)
+{
+	struct pool_desc *pool;
+
+	pool = hlist_entry(hnode, struct pool_desc, pool_hash);
+	return (pool->pool_name);
+}
+
+static int pool_hashkey_keycmp(const void *key, struct hlist_node *compared_hnode)
+{
+	char *pool_name;
+	struct pool_desc *pool;
+
+	pool_name = (char *)key;
+	pool = hlist_entry(compared_hnode, struct pool_desc, pool_hash);
+	return !strncmp(pool_name, pool->pool_name, LOV_MAXPOOLNAME);
+}
+
+static void *pool_hashobject(struct hlist_node *hnode)
+{
+	return hlist_entry(hnode, struct pool_desc, pool_hash);
+}
+
+static void pool_hashrefcount_get(cfs_hash_t *hs, struct hlist_node *hnode)
+{
+	struct pool_desc *pool;
+
+	pool = hlist_entry(hnode, struct pool_desc, pool_hash);
+	lov_pool_getref(pool);
+}
+
+static void pool_hashrefcount_put_locked(cfs_hash_t *hs,
+					 struct hlist_node *hnode)
+{
+	struct pool_desc *pool;
+
+	pool = hlist_entry(hnode, struct pool_desc, pool_hash);
+	lov_pool_putref_locked(pool);
+}
+
+cfs_hash_ops_t pool_hash_operations = {
+	.hs_hash	= pool_hashfn,
+	.hs_key	 = pool_key,
+	.hs_keycmp      = pool_hashkey_keycmp,
+	.hs_object      = pool_hashobject,
+	.hs_get	 = pool_hashrefcount_get,
+	.hs_put_locked  = pool_hashrefcount_put_locked,
+
+};
+
+#ifdef LPROCFS
+/* ifdef needed for liblustre support */
+/*
+ * pool /proc seq_file methods
+ */
+/*
+ * iterator is used to go through the target pool entries
+ * index is the current entry index in the lp_array[] array
+ * index >= pos returned to the seq_file interface
+ * pos is from 0 to (pool->pool_obds.op_count - 1)
+ */
+#define POOL_IT_MAGIC 0xB001CEA0
+struct pool_iterator {
+	int magic;
+	struct pool_desc *pool;
+	int idx;	/* from 0 to pool_tgt_size - 1 */
+};
+
+static void *pool_proc_next(struct seq_file *s, void *v, loff_t *pos)
+{
+	struct pool_iterator *iter = (struct pool_iterator *)s->private;
+	int prev_idx;
+
+	LASSERTF(iter->magic == POOL_IT_MAGIC, "%08X", iter->magic);
+
+	/* test if end of file */
+	if (*pos >= pool_tgt_count(iter->pool))
+		return NULL;
+
+	/* iterate to find a non empty entry */
+	prev_idx = iter->idx;
+	down_read(&pool_tgt_rw_sem(iter->pool));
+	iter->idx++;
+	if (iter->idx == pool_tgt_count(iter->pool)) {
+		iter->idx = prev_idx; /* we stay on the last entry */
+		up_read(&pool_tgt_rw_sem(iter->pool));
+		return NULL;
+	}
+	up_read(&pool_tgt_rw_sem(iter->pool));
+	(*pos)++;
+	/* return != NULL to continue */
+	return iter;
+}
+
+static void *pool_proc_start(struct seq_file *s, loff_t *pos)
+{
+	struct pool_desc *pool = (struct pool_desc *)s->private;
+	struct pool_iterator *iter;
+
+	lov_pool_getref(pool);
+	if ((pool_tgt_count(pool) == 0) ||
+	    (*pos >= pool_tgt_count(pool))) {
+		/* iter is not created, so stop() has no way to
+		 * find pool to dec ref */
+		lov_pool_putref(pool);
+		return NULL;
+	}
+
+	OBD_ALLOC_PTR(iter);
+	if (!iter)
+		return ERR_PTR(-ENOMEM);
+	iter->magic = POOL_IT_MAGIC;
+	iter->pool = pool;
+	iter->idx = 0;
+
+	/* we use seq_file private field to memorized iterator so
+	 * we can free it at stop() */
+	/* /!\ do not forget to restore it to pool before freeing it */
+	s->private = iter;
+	if (*pos > 0) {
+		loff_t i;
+		void *ptr;
+
+		i = 0;
+		do {
+		     ptr = pool_proc_next(s, &iter, &i);
+		} while ((i < *pos) && (ptr != NULL));
+		return ptr;
+	}
+	return iter;
+}
+
+static void pool_proc_stop(struct seq_file *s, void *v)
+{
+	struct pool_iterator *iter = (struct pool_iterator *)s->private;
+
+	/* in some cases stop() method is called 2 times, without
+	 * calling start() method (see seq_read() from fs/seq_file.c)
+	 * we have to free only if s->private is an iterator */
+	if ((iter) && (iter->magic == POOL_IT_MAGIC)) {
+		/* we restore s->private so next call to pool_proc_start()
+		 * will work */
+		s->private = iter->pool;
+		lov_pool_putref(iter->pool);
+		OBD_FREE_PTR(iter);
+	}
+	return;
+}
+
+static int pool_proc_show(struct seq_file *s, void *v)
+{
+	struct pool_iterator *iter = (struct pool_iterator *)v;
+	struct lov_tgt_desc *tgt;
+
+	LASSERTF(iter->magic == POOL_IT_MAGIC, "%08X", iter->magic);
+	LASSERT(iter->pool != NULL);
+	LASSERT(iter->idx <= pool_tgt_count(iter->pool));
+
+	down_read(&pool_tgt_rw_sem(iter->pool));
+	tgt = pool_tgt(iter->pool, iter->idx);
+	up_read(&pool_tgt_rw_sem(iter->pool));
+	if (tgt)
+		seq_printf(s, "%s\n", obd_uuid2str(&(tgt->ltd_uuid)));
+
+	return 0;
+}
+
+static struct seq_operations pool_proc_ops = {
+	.start	  = pool_proc_start,
+	.next	   = pool_proc_next,
+	.stop	   = pool_proc_stop,
+	.show	   = pool_proc_show,
+};
+
+static int pool_proc_open(struct inode *inode, struct file *file)
+{
+	int rc;
+
+	rc = seq_open(file, &pool_proc_ops);
+	if (!rc) {
+		struct seq_file *s = file->private_data;
+		s->private = PDE_DATA(inode);
+	}
+	return rc;
+}
+
+static struct file_operations pool_proc_operations = {
+	.open	   = pool_proc_open,
+	.read	   = seq_read,
+	.llseek	 = seq_lseek,
+	.release	= seq_release,
+};
+#endif /* LPROCFS */
+
+void lov_dump_pool(int level, struct pool_desc *pool)
+{
+	int i;
+
+	lov_pool_getref(pool);
+
+	CDEBUG(level, "pool "LOV_POOLNAMEF" has %d members\n",
+	       pool->pool_name, pool->pool_obds.op_count);
+	down_read(&pool_tgt_rw_sem(pool));
+
+	for (i = 0; i < pool_tgt_count(pool) ; i++) {
+		if (!pool_tgt(pool, i) || !(pool_tgt(pool, i))->ltd_exp)
+			continue;
+		CDEBUG(level, "pool "LOV_POOLNAMEF"[%d] = %s\n",
+		       pool->pool_name, i,
+		       obd_uuid2str(&((pool_tgt(pool, i))->ltd_uuid)));
+	}
+
+	up_read(&pool_tgt_rw_sem(pool));
+	lov_pool_putref(pool);
+}
+
+#define LOV_POOL_INIT_COUNT 2
+int lov_ost_pool_init(struct ost_pool *op, unsigned int count)
+{
+	ENTRY;
+
+	if (count == 0)
+		count = LOV_POOL_INIT_COUNT;
+	op->op_array = NULL;
+	op->op_count = 0;
+	init_rwsem(&op->op_rw_sem);
+	op->op_size = count;
+	OBD_ALLOC(op->op_array, op->op_size * sizeof(op->op_array[0]));
+	if (op->op_array == NULL) {
+		op->op_size = 0;
+		RETURN(-ENOMEM);
+	}
+	EXIT;
+	return 0;
+}
+
+/* Caller must hold write op_rwlock */
+int lov_ost_pool_extend(struct ost_pool *op, unsigned int min_count)
+{
+	__u32 *new;
+	int new_size;
+
+	LASSERT(min_count != 0);
+
+	if (op->op_count < op->op_size)
+		return 0;
+
+	new_size = max(min_count, 2 * op->op_size);
+	OBD_ALLOC(new, new_size * sizeof(op->op_array[0]));
+	if (new == NULL)
+		return -ENOMEM;
+
+	/* copy old array to new one */
+	memcpy(new, op->op_array, op->op_size * sizeof(op->op_array[0]));
+	OBD_FREE(op->op_array, op->op_size * sizeof(op->op_array[0]));
+	op->op_array = new;
+	op->op_size = new_size;
+	return 0;
+}
+
+int lov_ost_pool_add(struct ost_pool *op, __u32 idx, unsigned int min_count)
+{
+	int rc = 0, i;
+	ENTRY;
+
+	down_write(&op->op_rw_sem);
+
+	rc = lov_ost_pool_extend(op, min_count);
+	if (rc)
+		GOTO(out, rc);
+
+	/* search ost in pool array */
+	for (i = 0; i < op->op_count; i++) {
+		if (op->op_array[i] == idx)
+			GOTO(out, rc = -EEXIST);
+	}
+	/* ost not found we add it */
+	op->op_array[op->op_count] = idx;
+	op->op_count++;
+	EXIT;
+out:
+	up_write(&op->op_rw_sem);
+	return rc;
+}
+
+int lov_ost_pool_remove(struct ost_pool *op, __u32 idx)
+{
+	int i;
+	ENTRY;
+
+	down_write(&op->op_rw_sem);
+
+	for (i = 0; i < op->op_count; i++) {
+		if (op->op_array[i] == idx) {
+			memmove(&op->op_array[i], &op->op_array[i + 1],
+				(op->op_count - i - 1) * sizeof(op->op_array[0]));
+			op->op_count--;
+			up_write(&op->op_rw_sem);
+			EXIT;
+			return 0;
+		}
+	}
+
+	up_write(&op->op_rw_sem);
+	RETURN(-EINVAL);
+}
+
+int lov_ost_pool_free(struct ost_pool *op)
+{
+	ENTRY;
+
+	if (op->op_size == 0)
+		RETURN(0);
+
+	down_write(&op->op_rw_sem);
+
+	OBD_FREE(op->op_array, op->op_size * sizeof(op->op_array[0]));
+	op->op_array = NULL;
+	op->op_count = 0;
+	op->op_size = 0;
+
+	up_write(&op->op_rw_sem);
+	RETURN(0);
+}
+
+
+int lov_pool_new(struct obd_device *obd, char *poolname)
+{
+	struct lov_obd *lov;
+	struct pool_desc *new_pool;
+	int rc;
+	ENTRY;
+
+	lov = &(obd->u.lov);
+
+	if (strlen(poolname) > LOV_MAXPOOLNAME)
+		RETURN(-ENAMETOOLONG);
+
+	OBD_ALLOC_PTR(new_pool);
+	if (new_pool == NULL)
+		RETURN(-ENOMEM);
+
+	strncpy(new_pool->pool_name, poolname, LOV_MAXPOOLNAME);
+	new_pool->pool_name[LOV_MAXPOOLNAME] = '\0';
+	new_pool->pool_lobd = obd;
+	/* ref count init to 1 because when created a pool is always used
+	 * up to deletion
+	 */
+	atomic_set(&new_pool->pool_refcount, 1);
+	rc = lov_ost_pool_init(&new_pool->pool_obds, 0);
+	if (rc)
+	       GOTO(out_err, rc);
+
+	memset(&(new_pool->pool_rr), 0, sizeof(struct lov_qos_rr));
+	rc = lov_ost_pool_init(&new_pool->pool_rr.lqr_pool, 0);
+	if (rc)
+		GOTO(out_free_pool_obds, rc);
+
+	INIT_HLIST_NODE(&new_pool->pool_hash);
+
+#ifdef LPROCFS
+	/* we need this assert seq_file is not implementated for liblustre */
+	/* get ref for /proc file */
+	lov_pool_getref(new_pool);
+	new_pool->pool_proc_entry = lprocfs_add_simple(lov->lov_pool_proc_entry,
+						       poolname, new_pool,
+						       &pool_proc_operations);
+	if (IS_ERR(new_pool->pool_proc_entry)) {
+		CWARN("Cannot add proc pool entry "LOV_POOLNAMEF"\n", poolname);
+		new_pool->pool_proc_entry = NULL;
+		lov_pool_putref(new_pool);
+	}
+	CDEBUG(D_INFO, "pool %p - proc %p\n", new_pool, new_pool->pool_proc_entry);
+#endif
+
+	spin_lock(&obd->obd_dev_lock);
+	list_add_tail(&new_pool->pool_list, &lov->lov_pool_list);
+	lov->lov_pool_count++;
+	spin_unlock(&obd->obd_dev_lock);
+
+	/* add to find only when it fully ready  */
+	rc = cfs_hash_add_unique(lov->lov_pools_hash_body, poolname,
+				 &new_pool->pool_hash);
+	if (rc)
+		GOTO(out_err, rc = -EEXIST);
+
+	CDEBUG(D_CONFIG, LOV_POOLNAMEF" is pool #%d\n",
+	       poolname, lov->lov_pool_count);
+
+	RETURN(0);
+
+out_err:
+	spin_lock(&obd->obd_dev_lock);
+	list_del_init(&new_pool->pool_list);
+	lov->lov_pool_count--;
+	spin_unlock(&obd->obd_dev_lock);
+
+	lprocfs_remove(&new_pool->pool_proc_entry);
+
+	lov_ost_pool_free(&new_pool->pool_rr.lqr_pool);
+out_free_pool_obds:
+	lov_ost_pool_free(&new_pool->pool_obds);
+	OBD_FREE_PTR(new_pool);
+	return rc;
+}
+
+int lov_pool_del(struct obd_device *obd, char *poolname)
+{
+	struct lov_obd *lov;
+	struct pool_desc *pool;
+	ENTRY;
+
+	lov = &(obd->u.lov);
+
+	/* lookup and kill hash reference */
+	pool = cfs_hash_del_key(lov->lov_pools_hash_body, poolname);
+	if (pool == NULL)
+		RETURN(-ENOENT);
+
+	if (pool->pool_proc_entry != NULL) {
+		CDEBUG(D_INFO, "proc entry %p\n", pool->pool_proc_entry);
+		lprocfs_remove(&pool->pool_proc_entry);
+		lov_pool_putref(pool);
+	}
+
+	spin_lock(&obd->obd_dev_lock);
+	list_del_init(&pool->pool_list);
+	lov->lov_pool_count--;
+	spin_unlock(&obd->obd_dev_lock);
+
+	/* release last reference */
+	lov_pool_putref(pool);
+
+	RETURN(0);
+}
+
+
+int lov_pool_add(struct obd_device *obd, char *poolname, char *ostname)
+{
+	struct obd_uuid ost_uuid;
+	struct lov_obd *lov;
+	struct pool_desc *pool;
+	unsigned int lov_idx;
+	int rc;
+	ENTRY;
+
+	lov = &(obd->u.lov);
+
+	pool = cfs_hash_lookup(lov->lov_pools_hash_body, poolname);
+	if (pool == NULL)
+		RETURN(-ENOENT);
+
+	obd_str2uuid(&ost_uuid, ostname);
+
+
+	/* search ost in lov array */
+	obd_getref(obd);
+	for (lov_idx = 0; lov_idx < lov->desc.ld_tgt_count; lov_idx++) {
+		if (!lov->lov_tgts[lov_idx])
+			continue;
+		if (obd_uuid_equals(&ost_uuid,
+				    &(lov->lov_tgts[lov_idx]->ltd_uuid)))
+			break;
+	}
+	/* test if ost found in lov */
+	if (lov_idx == lov->desc.ld_tgt_count)
+		GOTO(out, rc = -EINVAL);
+
+	rc = lov_ost_pool_add(&pool->pool_obds, lov_idx, lov->lov_tgt_size);
+	if (rc)
+		GOTO(out, rc);
+
+	pool->pool_rr.lqr_dirty = 1;
+
+	CDEBUG(D_CONFIG, "Added %s to "LOV_POOLNAMEF" as member %d\n",
+	       ostname, poolname,  pool_tgt_count(pool));
+
+	EXIT;
+out:
+	obd_putref(obd);
+	lov_pool_putref(pool);
+	return rc;
+}
+
+int lov_pool_remove(struct obd_device *obd, char *poolname, char *ostname)
+{
+	struct obd_uuid ost_uuid;
+	struct lov_obd *lov;
+	struct pool_desc *pool;
+	unsigned int lov_idx;
+	int rc = 0;
+	ENTRY;
+
+	lov = &(obd->u.lov);
+
+	pool = cfs_hash_lookup(lov->lov_pools_hash_body, poolname);
+	if (pool == NULL)
+		RETURN(-ENOENT);
+
+	obd_str2uuid(&ost_uuid, ostname);
+
+	obd_getref(obd);
+	/* search ost in lov array, to get index */
+	for (lov_idx = 0; lov_idx < lov->desc.ld_tgt_count; lov_idx++) {
+		if (!lov->lov_tgts[lov_idx])
+			continue;
+
+		if (obd_uuid_equals(&ost_uuid,
+				    &(lov->lov_tgts[lov_idx]->ltd_uuid)))
+			break;
+	}
+
+	/* test if ost found in lov */
+	if (lov_idx == lov->desc.ld_tgt_count)
+		GOTO(out, rc = -EINVAL);
+
+	lov_ost_pool_remove(&pool->pool_obds, lov_idx);
+
+	pool->pool_rr.lqr_dirty = 1;
+
+	CDEBUG(D_CONFIG, "%s removed from "LOV_POOLNAMEF"\n", ostname,
+	       poolname);
+
+	EXIT;
+out:
+	obd_putref(obd);
+	lov_pool_putref(pool);
+	return rc;
+}
+
+int lov_check_index_in_pool(__u32 idx, struct pool_desc *pool)
+{
+	int i, rc;
+	ENTRY;
+
+	/* caller may no have a ref on pool if it got the pool
+	 * without calling lov_find_pool() (e.g. go through the lov pool
+	 * list)
+	 */
+	lov_pool_getref(pool);
+
+	down_read(&pool_tgt_rw_sem(pool));
+
+	for (i = 0; i < pool_tgt_count(pool); i++) {
+		if (pool_tgt_array(pool)[i] == idx)
+			GOTO(out, rc = 0);
+	}
+	rc = -ENOENT;
+	EXIT;
+out:
+	up_read(&pool_tgt_rw_sem(pool));
+
+	lov_pool_putref(pool);
+	return rc;
+}
+
+struct pool_desc *lov_find_pool(struct lov_obd *lov, char *poolname)
+{
+	struct pool_desc *pool;
+
+	pool = NULL;
+	if (poolname[0] != '\0') {
+		pool = cfs_hash_lookup(lov->lov_pools_hash_body, poolname);
+		if (pool == NULL)
+			CWARN("Request for an unknown pool ("LOV_POOLNAMEF")\n",
+			      poolname);
+		if ((pool != NULL) && (pool_tgt_count(pool) == 0)) {
+			CWARN("Request for an empty pool ("LOV_POOLNAMEF")\n",
+			       poolname);
+			/* pool is ignored, so we remove ref on it */
+			lov_pool_putref(pool);
+			pool = NULL;
+		}
+	}
+	return pool;
+}