NFSD: Hook up the filecache stat file

There has always been the capability of exporting filecache metrics
via /proc, but it was never hooked up. Let's surface these metrics
to enable better observability of the filecache.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 66c352bf61b1d454c0ce66badb5a1e1392d4df1a..7002edbf26870ece3444661c94203fc2c87d80f4 100644 (file)
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -25,6 +25,7 @@
 #include "state.h"
 #include "netns.h"
 #include "pnfs.h"
+#include "filecache.h"
 
 /*
  *     We have a single directory with several nodes in it.
@@ -45,6 +46,7 @@ enum {
        NFSD_Ports,
        NFSD_MaxBlkSize,
        NFSD_MaxConnections,
+       NFSD_Filecache,
        NFSD_SupportedEnctypes,
        /*
         * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
@@ -229,6 +231,13 @@ static const struct file_operations reply_cache_stats_operations = {
        .release        = single_release,
 };
 
+static const struct file_operations filecache_ops = {
+       .open           = nfsd_file_cache_stats_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
 /*----------------------------------------------------------------------------*/
 /*
  * payload - write methods
@@ -1370,6 +1379,7 @@ static int nfsd_fill_super(struct super_block *sb, struct fs_context *fc)
                [NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
                [NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
                [NFSD_MaxConnections] = {"max_connections", &transaction_ops, S_IWUSR|S_IRUGO},
+               [NFSD_Filecache] = {"filecache", &filecache_ops, S_IRUGO},
 #if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE)
                [NFSD_SupportedEnctypes] = {"supported_krb5_enctypes", &supported_enctypes_ops, S_IRUGO},
 #endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */