From 7973c1f15a0687f47ed70e591e4642d6fc4334d0 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 15 Jul 2008 17:58:14 -0400 Subject: [PATCH] NFS: Add mount options for controlling the lookup cache Add the following NFS-specific mount options to the parser. -o lookupcache=all /* Default: cache positive & negative dentries */ -o lookupcache=pos[itive] /* Don't cache negative dentries */ -o lookupcache=none /* Strict revalidation of all dentries */ Signed-off-by: Trond Myklebust --- fs/nfs/super.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/fs/nfs/super.c b/fs/nfs/super.c index 81686aeb1b5d..1e3558697219 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -91,6 +91,7 @@ enum { /* Mount options that take string arguments */ Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost, Opt_addr, Opt_mountaddr, Opt_clientaddr, + Opt_lookupcache, /* Special mount options */ Opt_userspace, Opt_deprecated, Opt_sloppy, @@ -154,6 +155,8 @@ static match_table_t nfs_mount_option_tokens = { { Opt_mounthost, "mounthost=%s" }, { Opt_mountaddr, "mountaddr=%s" }, + { Opt_lookupcache, "lookupcache=%s" }, + { Opt_err, NULL } }; @@ -200,6 +203,22 @@ static match_table_t nfs_secflavor_tokens = { { Opt_sec_err, NULL } }; +enum { + Opt_lookupcache_all, Opt_lookupcache_positive, + Opt_lookupcache_none, + + Opt_lookupcache_err +}; + +static match_table_t nfs_lookupcache_tokens = { + { Opt_lookupcache_all, "all" }, + { Opt_lookupcache_positive, "pos" }, + { Opt_lookupcache_positive, "positive" }, + { Opt_lookupcache_none, "none" }, + + { Opt_lookupcache_err, NULL } +}; + static void nfs_umount_begin(struct super_block *); static int nfs_statfs(struct dentry *, struct kstatfs *); @@ -1250,6 +1269,30 @@ static int nfs_parse_mount_options(char *raw, &mnt->mount_server.addrlen); kfree(string); break; + case Opt_lookupcache: + string = match_strdup(args); + if (string == NULL) + goto out_nomem; + token = match_token(string, + nfs_lookupcache_tokens, args); + kfree(string); + switch (token) { + case Opt_lookupcache_all: + mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE); + break; + case Opt_lookupcache_positive: + mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE; + mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG; + break; + case Opt_lookupcache_none: + mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE; + break; + default: + errors++; + dfprintk(MOUNT, "NFS: invalid " + "lookupcache argument\n"); + }; + break; /* * Special options -- 2.20.1