NFSv4.1: make deviceid cache global

Move deviceid cache from the pnfs files layout driver to the
generic layer in preparation for the objects layout driver.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>

1 files changed, 13 insertions, 91 deletions

diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c
index 42e326637271..eda4527a57eb 100644
--- a/fs/nfs/nfs4filelayoutdev.c
+++ b/fs/nfs/nfs4filelayoutdev.c
@@ -37,30 +37,6 @@
 #define NFSDBG_FACILITY		NFSDBG_PNFS_LD
 
 /*
- * Device ID RCU cache. A device ID is unique per client ID and layout type.
- */
-#define NFS4_FL_DEVICE_ID_HASH_BITS	5
-#define NFS4_FL_DEVICE_ID_HASH_SIZE	(1 << NFS4_FL_DEVICE_ID_HASH_BITS)
-#define NFS4_FL_DEVICE_ID_HASH_MASK	(NFS4_FL_DEVICE_ID_HASH_SIZE - 1)
-
-static inline u32
-nfs4_fl_deviceid_hash(struct nfs4_deviceid *id)
-{
-	unsigned char *cptr = (unsigned char *)id->data;
-	unsigned int nbytes = NFS4_DEVICEID4_SIZE;
-	u32 x = 0;
-
-	while (nbytes--) {
-		x *= 37;
-		x += *cptr++;
-	}
-	return x & NFS4_FL_DEVICE_ID_HASH_MASK;
-}
-
-static struct hlist_head filelayout_deviceid_cache[NFS4_FL_DEVICE_ID_HASH_SIZE];
-static DEFINE_SPINLOCK(filelayout_deviceid_lock);
-
-/*
  * Data server cache
  *
  * Data servers can be mapped to different device ids.
@@ -89,27 +65,6 @@ print_ds(struct nfs4_pnfs_ds *ds)
 		ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
 }
 
-void
-print_ds_list(struct nfs4_file_layout_dsaddr *dsaddr)
-{
-	int i;
-
-	ifdebug(FACILITY) {
-		printk("%s dsaddr->ds_num %d\n", __func__,
-		       dsaddr->ds_num);
-		for (i = 0; i < dsaddr->ds_num; i++)
-			print_ds(dsaddr->ds_list[i]);
-	}
-}
-
-void print_deviceid(struct nfs4_deviceid *id)
-{
-	u32 *p = (u32 *)id;
-
-	dprintk("%s: device id= [%x%x%x%x]\n", __func__,
-		p[0], p[1], p[2], p[3]);
-}
-
 /* nfs4_ds_cache_lock is held */
 static struct nfs4_pnfs_ds *
 _data_server_lookup_locked(u32 ip_addr, u32 port)
@@ -207,7 +162,7 @@ nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 	struct nfs4_pnfs_ds *ds;
 	int i;
 
-	print_deviceid(&dsaddr->deviceid);
+	nfs4_print_deviceid(&dsaddr->id_node.deviceid);
 
 	for (i = 0; i < dsaddr->ds_num; i++) {
 		ds = dsaddr->ds_list[i];
@@ -431,8 +386,8 @@ decode_device(struct inode *ino, struct pnfs_device *pdev, gfp_t gfp_flags)
 	dsaddr->stripe_indices = stripe_indices;
 	stripe_indices = NULL;
 	dsaddr->ds_num = num;
-	dsaddr->nfs_client = NFS_SERVER(ino)->nfs_client;
-	memcpy(&dsaddr->deviceid, &pdev->dev_id, sizeof(pdev->dev_id));
+	nfs4_init_deviceid_node(&dsaddr->id_node, NFS_SERVER(ino)->nfs_client,
+				&pdev->dev_id);
 
 	for (i = 0; i < dsaddr->ds_num; i++) {
 		int j;
@@ -505,8 +460,8 @@ out_err:
 static struct nfs4_file_layout_dsaddr *
 decode_and_add_device(struct inode *inode, struct pnfs_device *dev, gfp_t gfp_flags)
 {
-	struct nfs4_file_layout_dsaddr *d, *new;
-	long hash;
+	struct nfs4_deviceid_node *d;
+	struct nfs4_file_layout_dsaddr *n, *new;
 
 	new = decode_device(inode, dev, gfp_flags);
 	if (!new) {
@@ -515,20 +470,13 @@ decode_and_add_device(struct inode *inode, struct pnfs_device *dev, gfp_t gfp_fl
 		return NULL;
 	}
 
-	spin_lock(&filelayout_deviceid_lock);
-	d = nfs4_fl_find_get_deviceid(new->nfs_client, &new->deviceid);
-	if (d) {
-		spin_unlock(&filelayout_deviceid_lock);
+	d = nfs4_insert_deviceid_node(&new->id_node);
+	n = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
+	if (n != new) {
 		nfs4_fl_free_deviceid(new);
-		return d;
+		return n;
 	}
 
-	INIT_HLIST_NODE(&new->node);
-	atomic_set(&new->ref, 1);
-	hash = nfs4_fl_deviceid_hash(&new->deviceid);
-	hlist_add_head_rcu(&new->node, &filelayout_deviceid_cache[hash]);
-	spin_unlock(&filelayout_deviceid_lock);
-
 	return new;
 }
 
@@ -600,34 +548,8 @@ out_free:
 void
 nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 {
-	if (atomic_dec_and_lock(&dsaddr->ref, &filelayout_deviceid_lock)) {
-		hlist_del_rcu(&dsaddr->node);
-		spin_unlock(&filelayout_deviceid_lock);
-
-		synchronize_rcu();
+	if (nfs4_put_deviceid_node(&dsaddr->id_node))
 		nfs4_fl_free_deviceid(dsaddr);
-	}
-}
-
-struct nfs4_file_layout_dsaddr *
-nfs4_fl_find_get_deviceid(struct nfs_client *clp, struct nfs4_deviceid *id)
-{
-	struct nfs4_file_layout_dsaddr *d;
-	struct hlist_node *n;
-	long hash = nfs4_fl_deviceid_hash(id);
-
-	rcu_read_lock();
-	hlist_for_each_entry_rcu(d, n, &filelayout_deviceid_cache[hash], node) {
-		if (d->nfs_client == clp && !memcmp(&d->deviceid, id, sizeof(*id))) {
-			if (!atomic_inc_not_zero(&d->ref))
-				goto fail;
-			rcu_read_unlock();
-			return d;
-		}
-	}
-fail:
-	rcu_read_unlock();
-	return NULL;
 }
 
 /*
@@ -675,15 +597,15 @@ static void
 filelayout_mark_devid_negative(struct nfs4_file_layout_dsaddr *dsaddr,
 			       int err, u32 ds_addr)
 {
-	u32 *p = (u32 *)&dsaddr->deviceid;
+	u32 *p = (u32 *)&dsaddr->id_node.deviceid;
 
 	printk(KERN_ERR "NFS: data server %x connection error %d."
 		" Deviceid [%x%x%x%x] marked out of use.\n",
 		ds_addr, err, p[0], p[1], p[2], p[3]);
 
-	spin_lock(&filelayout_deviceid_lock);
+	spin_lock(&nfs4_ds_cache_lock);
 	dsaddr->flags |= NFS4_DEVICE_ID_NEG_ENTRY;
-	spin_unlock(&filelayout_deviceid_lock);
+	spin_unlock(&nfs4_ds_cache_lock);
 }
 
 struct nfs4_pnfs_ds *