dlm: move recover idr to xarray datastructure

According to kdoc idr is deprecated and xarrays should be used nowadays.
This patch is moving the recover idr implementation to xarray
datastructure.

Signed-off-by: Alexander Aring <[e-mail]>
Signed-off-by: David Teigland <[e-mail]>

fs/dlm/dlm_internal.h

···
 #include <linux/miscdevice.h>
 #include <linux/rhashtable.h>
 #include <linux/mutex.h>
-#include <linux/idr.h>
 #include <linux/xarray.h>
 #include <linux/ratelimit.h>
 #include <linux/uaccess.h>
···
 	int			res_nodeid;
 	int			res_master_nodeid;
 	int			res_dir_nodeid;
-	int			res_id;		/* for ls_recover_idr */
+	unsigned long		res_id;		/* for ls_recover_xa */
 	uint32_t                res_lvbseq;
 	uint32_t		res_hash;
 	unsigned long		res_toss_time;
···
 	struct list_head	ls_recover_list;
 	spinlock_t		ls_recover_list_lock;
 	int			ls_recover_list_count;
-	struct idr		ls_recover_idr;
-	spinlock_t		ls_recover_idr_lock;
+	struct xarray		ls_recover_xa;
+	spinlock_t		ls_recover_xa_lock;
 	wait_queue_head_t	ls_wait_general;
 	wait_queue_head_t	ls_recover_lock_wait;
 	spinlock_t		ls_clear_proc_locks;

fs/dlm/lockspace.c

···
 
 	INIT_LIST_HEAD(&ls->ls_recover_list);
 	spin_lock_init(&ls->ls_recover_list_lock);
-	idr_init(&ls->ls_recover_idr);
-	spin_lock_init(&ls->ls_recover_idr_lock);
+	xa_init_flags(&ls->ls_recover_xa, XA_FLAGS_ALLOC | XA_FLAGS_LOCK_BH);
+	spin_lock_init(&ls->ls_recover_xa_lock);
 	ls->ls_recover_list_count = 0;
 	init_waitqueue_head(&ls->ls_wait_general);
 	INIT_LIST_HEAD(&ls->ls_masters_list);
···
 	spin_lock_bh(&lslist_lock);
 	list_del(&ls->ls_list);
 	spin_unlock_bh(&lslist_lock);
-	idr_destroy(&ls->ls_recover_idr);
+	xa_destroy(&ls->ls_recover_xa);
 	kfree(ls->ls_recover_buf);
  out_lkbxa:
 	xa_destroy(&ls->ls_lkbxa);
···
 
 	dlm_delete_debug_file(ls);
 
-	idr_destroy(&ls->ls_recover_idr);
+	xa_destroy(&ls->ls_recover_xa);
 	kfree(ls->ls_recover_buf);
 
 	/*

fs/dlm/recover.c

···
 	spin_unlock_bh(&ls->ls_recover_list_lock);
 }
 
-static int recover_idr_empty(struct dlm_ls *ls)
+static int recover_xa_empty(struct dlm_ls *ls)
 {
 	int empty = 1;
 
-	spin_lock_bh(&ls->ls_recover_idr_lock);
+	spin_lock_bh(&ls->ls_recover_xa_lock);
 	if (ls->ls_recover_list_count)
 		empty = 0;
-	spin_unlock_bh(&ls->ls_recover_idr_lock);
+	spin_unlock_bh(&ls->ls_recover_xa_lock);
 
 	return empty;
 }
 
-static int recover_idr_add(struct dlm_rsb *r)
+static int recover_xa_add(struct dlm_rsb *r)
 {
 	struct dlm_ls *ls = r->res_ls;
+	struct xa_limit limit = {
+		.min = 1,
+		.max = UINT_MAX,
+	};
+	uint32_t id;
 	int rv;
 
-	spin_lock_bh(&ls->ls_recover_idr_lock);
+	spin_lock_bh(&ls->ls_recover_xa_lock);
 	if (r->res_id) {
 		rv = -1;
 		goto out_unlock;
 	}
-	rv = idr_alloc(&ls->ls_recover_idr, r, 1, 0, GFP_NOWAIT);
+	rv = xa_alloc(&ls->ls_recover_xa, &id, r, limit, GFP_ATOMIC);
 	if (rv < 0)
 		goto out_unlock;
 
-	r->res_id = rv;
+	r->res_id = id;
 	ls->ls_recover_list_count++;
 	dlm_hold_rsb(r);
 	rv = 0;
 out_unlock:
-	spin_unlock_bh(&ls->ls_recover_idr_lock);
+	spin_unlock_bh(&ls->ls_recover_xa_lock);
 	return rv;
 }
 
-static void recover_idr_del(struct dlm_rsb *r)
+static void recover_xa_del(struct dlm_rsb *r)
 {
 	struct dlm_ls *ls = r->res_ls;
 
-	spin_lock_bh(&ls->ls_recover_idr_lock);
-	idr_remove(&ls->ls_recover_idr, r->res_id);
+	spin_lock_bh(&ls->ls_recover_xa_lock);
+	xa_erase_bh(&ls->ls_recover_xa, r->res_id);
 	r->res_id = 0;
 	ls->ls_recover_list_count--;
-	spin_unlock_bh(&ls->ls_recover_idr_lock);
+	spin_unlock_bh(&ls->ls_recover_xa_lock);
 
 	dlm_put_rsb(r);
 }
 
-static struct dlm_rsb *recover_idr_find(struct dlm_ls *ls, uint64_t id)
+static struct dlm_rsb *recover_xa_find(struct dlm_ls *ls, uint64_t id)
 {
 	struct dlm_rsb *r;
 
-	spin_lock_bh(&ls->ls_recover_idr_lock);
-	r = idr_find(&ls->ls_recover_idr, (int)id);
-	spin_unlock_bh(&ls->ls_recover_idr_lock);
+	spin_lock_bh(&ls->ls_recover_xa_lock);
+	r = xa_load(&ls->ls_recover_xa, (int)id);
+	spin_unlock_bh(&ls->ls_recover_xa_lock);
 	return r;
 }
 
-static void recover_idr_clear(struct dlm_ls *ls)
+static void recover_xa_clear(struct dlm_ls *ls)
 {
 	struct dlm_rsb *r;
-	int id;
+	unsigned long id;
 
-	spin_lock_bh(&ls->ls_recover_idr_lock);
+	spin_lock_bh(&ls->ls_recover_xa_lock);
 
-	idr_for_each_entry(&ls->ls_recover_idr, r, id) {
-		idr_remove(&ls->ls_recover_idr, id);
+	xa_for_each(&ls->ls_recover_xa, id, r) {
+		xa_erase_bh(&ls->ls_recover_xa, id);
 		r->res_id = 0;
 		r->res_recover_locks_count = 0;
 		ls->ls_recover_list_count--;
···
 			  ls->ls_recover_list_count);
 		ls->ls_recover_list_count = 0;
 	}
-	spin_unlock_bh(&ls->ls_recover_idr_lock);
+	spin_unlock_bh(&ls->ls_recover_xa_lock);
 }
 
 
···
 		set_new_master(r);
 		error = 0;
 	} else {
-		recover_idr_add(r);
+		recover_xa_add(r);
 		error = dlm_send_rcom_lookup(r, dir_nodeid, seq);
 	}
 
···
 
 	log_rinfo(ls, "dlm_recover_masters %u of %u", count, total);
 
-	error = dlm_wait_function(ls, &recover_idr_empty);
+	error = dlm_wait_function(ls, &recover_xa_empty);
  out:
 	if (error)
-		recover_idr_clear(ls);
+		recover_xa_clear(ls);
 	return error;
 }
 
···
 	struct dlm_rsb *r;
 	int ret_nodeid, new_master;
 
-	r = recover_idr_find(ls, le64_to_cpu(rc->rc_id));
+	r = recover_xa_find(ls, le64_to_cpu(rc->rc_id));
 	if (!r) {
 		log_error(ls, "dlm_recover_master_reply no id %llx",
 			  (unsigned long long)le64_to_cpu(rc->rc_id));
···
 	r->res_nodeid = new_master;
 	set_new_master(r);
 	unlock_rsb(r);
-	recover_idr_del(r);
+	recover_xa_del(r);
 
-	if (recover_idr_empty(ls))
+	if (recover_xa_empty(ls))
 		wake_up(&ls->ls_wait_general);
  out:
 	return 0;