[PATCH 11/16] cifs: option to set unlimited number of cached dirs

[Steve French <smfrench@gmail.com>]

From: Shyam Prasad N <sprasad@microsoft.com>

Today we can control the number of cached dirs on the system using
the mount option max_cached_dirs. The default value is 16.

This change allows setting this option to a special value of 0,
which means unlimited number of cached dirs. Shrinker can still
evict the cached dirs.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
---
 fs/smb/client/cached_dir.c |  5 +++--
 fs/smb/client/fs_context.c | 10 +++++-----
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/fs/smb/client/cached_dir.c b/fs/smb/client/cached_dir.c
index 921a6f2c3c51..ecdc6907cf6d 100644
--- a/fs/smb/client/cached_dir.c
+++ b/fs/smb/client/cached_dir.c
@@ -1255,9 +1255,10 @@ static struct cached_fid *find_or_create_cached_dir(struct cached_fids *cfids,
 	if (lookup_only) {
 		return NULL;
 	}
-	if (cfids->num_entries >= max_cached_dirs) {
+
+	if (max_cached_dirs && cfids->num_entries >= max_cached_dirs)
 		return NULL;
-	}
+
 	cfid = init_cached_dir(path);
 	if (cfid == NULL) {
 		return NULL;
diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c
index 9bb41114237f..f2cc5530447a 100644
--- a/fs/smb/client/fs_context.c
+++ b/fs/smb/client/fs_context.c
@@ -1523,12 +1523,12 @@ static int smb3_fs_context_parse_param(struct fs_context *fc,
 		ctx->max_channels = result.uint_32;
 		break;
 	case Opt_max_cached_dirs:
-		if (result.uint_32 < 1) {
-			cifs_errorf(fc, "%s: Invalid max_cached_dirs, needs to be 1 or more\n",
-				    __func__);
-			goto cifs_parse_mount_err;
+		if (result.uint_32 > 0) {
+			ctx->max_cached_dirs = result.uint_32;
+		} else {
+			/* 0 means unlimited */
+			ctx->max_cached_dirs = 0;
 		}
-		ctx->max_cached_dirs = result.uint_32;
 		break;
 	case Opt_handletimeout:
 		ctx->handle_timeout = result.uint_32;
-- 
2.53.0