From: Trond Myklebust Date: Tue, 7 Feb 2012 14:59:05 -0500 Subject: [1/2] NFSv4: Reduce the footprint of the idmapper commit d073e9b541e1ac3f52d72c3a153855d9a9ee3278 upstream. Instead of pre-allocating the storage for all the strings, we can significantly reduce the size of that table by doing the allocation when we do the downcall. Signed-off-by: Trond Myklebust Reviewed-by: Jeff Layton [bwh: Backported to 3.2: adjust context in nfs_idmap_delete()] --- fs/nfs/idmap.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) --- a/fs/nfs/idmap.c +++ b/fs/nfs/idmap.c @@ -318,7 +318,7 @@ unsigned long ih_expires; __u32 ih_id; size_t ih_namelen; - char ih_name[IDMAP_NAMESZ]; + const char *ih_name; }; struct idmap_hashtable { @@ -382,11 +382,16 @@ nfs_idmap_delete(struct nfs_client *clp) { struct idmap *idmap = clp->cl_idmap; + int i; if (!idmap) return; rpc_unlink(idmap->idmap_dentry); clp->cl_idmap = NULL; + for (i = 0; i < ARRAY_SIZE(idmap->idmap_user_hash.h_entries); i++) + kfree(idmap->idmap_user_hash.h_entries[i].ih_name); + for (i = 0; i < ARRAY_SIZE(idmap->idmap_group_hash.h_entries); i++) + kfree(idmap->idmap_group_hash.h_entries[i].ih_name); kfree(idmap); } @@ -449,9 +454,14 @@ idmap_update_entry(struct idmap_hashent *he, const char *name, size_t namelen, __u32 id) { + char *str = kmalloc(namelen + 1, GFP_KERNEL); + if (str == NULL) + return; + kfree(he->ih_name); he->ih_id = id; - memcpy(he->ih_name, name, namelen); - he->ih_name[namelen] = '\0'; + memcpy(str, name, namelen); + str[namelen] = '\0'; + he->ih_name = str; he->ih_namelen = namelen; he->ih_expires = jiffies + nfs_idmap_cache_timeout; }