nfs41: pull data server cache from file layout to generic pnfs
Also pull nfs4_pnfs_ds_addr and nfs4_pnfs_ds to generic pnfs.
They can all be reused by flexfile layout as well.
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
diff --git a/fs/nfs/pnfs_nfs.c b/fs/nfs/pnfs_nfs.c
index fd2a2f0..3bb2b74 100644
--- a/fs/nfs/pnfs_nfs.c
+++ b/fs/nfs/pnfs_nfs.c
@@ -13,6 +13,8 @@
#include "internal.h"
#include "pnfs.h"
+#define NFSDBG_FACILITY NFSDBG_PNFS
+
static void pnfs_generic_fenceme(struct inode *inode,
struct pnfs_layout_hdr *lo)
{
@@ -290,3 +292,243 @@
return PNFS_ATTEMPTED;
}
EXPORT_SYMBOL_GPL(pnfs_generic_commit_pagelist);
+
+/*
+ * Data server cache
+ *
+ * Data servers can be mapped to different device ids.
+ * nfs4_pnfs_ds reference counting
+ * - set to 1 on allocation
+ * - incremented when a device id maps a data server already in the cache.
+ * - decremented when deviceid is removed from the cache.
+ */
+static DEFINE_SPINLOCK(nfs4_ds_cache_lock);
+static LIST_HEAD(nfs4_data_server_cache);
+
+/* Debug routines */
+static void
+print_ds(struct nfs4_pnfs_ds *ds)
+{
+ if (ds == NULL) {
+ printk(KERN_WARNING "%s NULL device\n", __func__);
+ return;
+ }
+ printk(KERN_WARNING " ds %s\n"
+ " ref count %d\n"
+ " client %p\n"
+ " cl_exchange_flags %x\n",
+ ds->ds_remotestr,
+ atomic_read(&ds->ds_count), ds->ds_clp,
+ ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
+}
+
+static bool
+same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2)
+{
+ struct sockaddr_in *a, *b;
+ struct sockaddr_in6 *a6, *b6;
+
+ if (addr1->sa_family != addr2->sa_family)
+ return false;
+
+ switch (addr1->sa_family) {
+ case AF_INET:
+ a = (struct sockaddr_in *)addr1;
+ b = (struct sockaddr_in *)addr2;
+
+ if (a->sin_addr.s_addr == b->sin_addr.s_addr &&
+ a->sin_port == b->sin_port)
+ return true;
+ break;
+
+ case AF_INET6:
+ a6 = (struct sockaddr_in6 *)addr1;
+ b6 = (struct sockaddr_in6 *)addr2;
+
+ /* LINKLOCAL addresses must have matching scope_id */
+ if (ipv6_addr_src_scope(&a6->sin6_addr) ==
+ IPV6_ADDR_SCOPE_LINKLOCAL &&
+ a6->sin6_scope_id != b6->sin6_scope_id)
+ return false;
+
+ if (ipv6_addr_equal(&a6->sin6_addr, &b6->sin6_addr) &&
+ a6->sin6_port == b6->sin6_port)
+ return true;
+ break;
+
+ default:
+ dprintk("%s: unhandled address family: %u\n",
+ __func__, addr1->sa_family);
+ return false;
+ }
+
+ return false;
+}
+
+static bool
+_same_data_server_addrs_locked(const struct list_head *dsaddrs1,
+ const struct list_head *dsaddrs2)
+{
+ struct nfs4_pnfs_ds_addr *da1, *da2;
+
+ /* step through both lists, comparing as we go */
+ for (da1 = list_first_entry(dsaddrs1, typeof(*da1), da_node),
+ da2 = list_first_entry(dsaddrs2, typeof(*da2), da_node);
+ da1 != NULL && da2 != NULL;
+ da1 = list_entry(da1->da_node.next, typeof(*da1), da_node),
+ da2 = list_entry(da2->da_node.next, typeof(*da2), da_node)) {
+ if (!same_sockaddr((struct sockaddr *)&da1->da_addr,
+ (struct sockaddr *)&da2->da_addr))
+ return false;
+ }
+ if (da1 == NULL && da2 == NULL)
+ return true;
+
+ return false;
+}
+
+/*
+ * Lookup DS by addresses. nfs4_ds_cache_lock is held
+ */
+static struct nfs4_pnfs_ds *
+_data_server_lookup_locked(const struct list_head *dsaddrs)
+{
+ struct nfs4_pnfs_ds *ds;
+
+ list_for_each_entry(ds, &nfs4_data_server_cache, ds_node)
+ if (_same_data_server_addrs_locked(&ds->ds_addrs, dsaddrs))
+ return ds;
+ return NULL;
+}
+
+static void destroy_ds(struct nfs4_pnfs_ds *ds)
+{
+ struct nfs4_pnfs_ds_addr *da;
+
+ dprintk("--> %s\n", __func__);
+ ifdebug(FACILITY)
+ print_ds(ds);
+
+ nfs_put_client(ds->ds_clp);
+
+ while (!list_empty(&ds->ds_addrs)) {
+ da = list_first_entry(&ds->ds_addrs,
+ struct nfs4_pnfs_ds_addr,
+ da_node);
+ list_del_init(&da->da_node);
+ kfree(da->da_remotestr);
+ kfree(da);
+ }
+
+ kfree(ds->ds_remotestr);
+ kfree(ds);
+}
+
+void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds)
+{
+ if (atomic_dec_and_lock(&ds->ds_count,
+ &nfs4_ds_cache_lock)) {
+ list_del_init(&ds->ds_node);
+ spin_unlock(&nfs4_ds_cache_lock);
+ destroy_ds(ds);
+ }
+}
+EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_put);
+
+/*
+ * Create a string with a human readable address and port to avoid
+ * complicated setup around many dprinks.
+ */
+static char *
+nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
+{
+ struct nfs4_pnfs_ds_addr *da;
+ char *remotestr;
+ size_t len;
+ char *p;
+
+ len = 3; /* '{', '}' and eol */
+ list_for_each_entry(da, dsaddrs, da_node) {
+ len += strlen(da->da_remotestr) + 1; /* string plus comma */
+ }
+
+ remotestr = kzalloc(len, gfp_flags);
+ if (!remotestr)
+ return NULL;
+
+ p = remotestr;
+ *(p++) = '{';
+ len--;
+ list_for_each_entry(da, dsaddrs, da_node) {
+ size_t ll = strlen(da->da_remotestr);
+
+ if (ll > len)
+ goto out_err;
+
+ memcpy(p, da->da_remotestr, ll);
+ p += ll;
+ len -= ll;
+
+ if (len < 1)
+ goto out_err;
+ (*p++) = ',';
+ len--;
+ }
+ if (len < 2)
+ goto out_err;
+ *(p++) = '}';
+ *p = '\0';
+ return remotestr;
+out_err:
+ kfree(remotestr);
+ return NULL;
+}
+
+/*
+ * Given a list of multipath struct nfs4_pnfs_ds_addr, add it to ds cache if
+ * uncached and return cached struct nfs4_pnfs_ds.
+ */
+struct nfs4_pnfs_ds *
+nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
+{
+ struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
+ char *remotestr;
+
+ if (list_empty(dsaddrs)) {
+ dprintk("%s: no addresses defined\n", __func__);
+ goto out;
+ }
+
+ ds = kzalloc(sizeof(*ds), gfp_flags);
+ if (!ds)
+ goto out;
+
+ /* this is only used for debugging, so it's ok if its NULL */
+ remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
+
+ spin_lock(&nfs4_ds_cache_lock);
+ tmp_ds = _data_server_lookup_locked(dsaddrs);
+ if (tmp_ds == NULL) {
+ INIT_LIST_HEAD(&ds->ds_addrs);
+ list_splice_init(dsaddrs, &ds->ds_addrs);
+ ds->ds_remotestr = remotestr;
+ atomic_set(&ds->ds_count, 1);
+ INIT_LIST_HEAD(&ds->ds_node);
+ ds->ds_clp = NULL;
+ list_add(&ds->ds_node, &nfs4_data_server_cache);
+ dprintk("%s add new data server %s\n", __func__,
+ ds->ds_remotestr);
+ } else {
+ kfree(remotestr);
+ kfree(ds);
+ atomic_inc(&tmp_ds->ds_count);
+ dprintk("%s data server %s found, inc'ed ds_count to %d\n",
+ __func__, tmp_ds->ds_remotestr,
+ atomic_read(&tmp_ds->ds_count));
+ ds = tmp_ds;
+ }
+ spin_unlock(&nfs4_ds_cache_lock);
+out:
+ return ds;
+}
+EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_add);
