Hi,
The Fedora 16 kernel 3.2.10-3.fc16 has patches that should reduce the
memory requirements of the old id mapper. The relevant changelog entry is:
* Wed Mar 14 2012 Steve Dickson <ste...@redhat.com>
- Reduce the foot print of the NFSv4 idmapping coda (bz 593035)
I have attached the patches they have applied.
The following bug report shows that also RHEL6 is affected by this bug:
https://bugzilla.redhat.com/show_bug.cgi?id=730045
I assume the patches they applied to their future 6.3 kernel are the
same as the Fedora patches and they confirm they fix the issue.
If switching to the new ID mapper code (bug 657078) is not considered
for the Wheezy kernel, please consider applying these patches to the 3.2
kernel in sid/testing.
Regards,
Rik
diff -up linux-3.2.noarch/fs/nfs/idmap.c.orig linux-3.2.noarch/fs/nfs/idmap.c
--- linux-3.2.noarch/fs/nfs/idmap.c.orig 2012-02-07 07:12:52.585471833 -0500
+++ linux-3.2.noarch/fs/nfs/idmap.c 2012-03-14 13:08:37.462928792 -0400
@@ -360,7 +360,7 @@ struct idmap_hashent {
unsigned long ih_expires;
__u32 ih_id;
size_t ih_namelen;
- char ih_name[IDMAP_NAMESZ];
+ const char *ih_name;
};
struct idmap_hashtable {
@@ -424,11 +424,16 @@ void
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);
}
@@ -491,9 +496,14 @@ static void
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;
}
diff -up linux-3.2.noarch/fs/nfs/idmap.c.orig linux-3.2.noarch/fs/nfs/idmap.c
--- linux-3.2.noarch/fs/nfs/idmap.c.orig 2012-03-14 13:08:37.462928792 -0400
+++ linux-3.2.noarch/fs/nfs/idmap.c 2012-03-14 13:10:17.076030982 -0400
@@ -365,7 +365,7 @@ struct idmap_hashent {
struct idmap_hashtable {
__u8 h_type;
- struct idmap_hashent h_entries[IDMAP_HASH_SZ];
+ struct idmap_hashent *h_entries;
};
struct idmap {
@@ -420,20 +420,39 @@ nfs_idmap_new(struct nfs_client *clp)
return 0;
}
+static void
+idmap_alloc_hashtable(struct idmap_hashtable *h)
+{
+ if (h->h_entries != NULL)
+ return;
+ h->h_entries = kcalloc(IDMAP_HASH_SZ,
+ sizeof(*h->h_entries),
+ GFP_KERNEL);
+}
+
+static void
+idmap_free_hashtable(struct idmap_hashtable *h)
+{
+ int i;
+
+ if (h->h_entries == NULL)
+ return;
+ for (i = 0; i < IDMAP_HASH_SZ; i++)
+ kfree(h->h_entries[i].ih_name);
+ kfree(h->h_entries);
+}
+
void
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);
+ idmap_free_hashtable(&idmap->idmap_user_hash);
+ idmap_free_hashtable(&idmap->idmap_group_hash);
kfree(idmap);
}
@@ -443,6 +462,8 @@ nfs_idmap_delete(struct nfs_client *clp)
static inline struct idmap_hashent *
idmap_name_hash(struct idmap_hashtable* h, const char *name, size_t len)
{
+ if (h->h_entries == NULL)
+ return NULL;
return &h->h_entries[fnvhash32(name, len) % IDMAP_HASH_SZ];
}
@@ -451,6 +472,8 @@ idmap_lookup_name(struct idmap_hashtable
{
struct idmap_hashent *he = idmap_name_hash(h, name, len);
+ if (he == NULL)
+ return NULL;
if (he->ih_namelen != len || memcmp(he->ih_name, name, len) != 0)
return NULL;
if (time_after(jiffies, he->ih_expires))
@@ -461,6 +484,8 @@ idmap_lookup_name(struct idmap_hashtable
static inline struct idmap_hashent *
idmap_id_hash(struct idmap_hashtable* h, __u32 id)
{
+ if (h->h_entries == NULL)
+ return NULL;
return &h->h_entries[fnvhash32(&id, sizeof(id)) % IDMAP_HASH_SZ];
}
@@ -468,6 +493,9 @@ static struct idmap_hashent *
idmap_lookup_id(struct idmap_hashtable *h, __u32 id)
{
struct idmap_hashent *he = idmap_id_hash(h, id);
+
+ if (he == NULL)
+ return NULL;
if (he->ih_id != id || he->ih_namelen == 0)
return NULL;
if (time_after(jiffies, he->ih_expires))
@@ -483,12 +511,14 @@ idmap_lookup_id(struct idmap_hashtable *
static inline struct idmap_hashent *
idmap_alloc_name(struct idmap_hashtable *h, char *name, size_t len)
{
+ idmap_alloc_hashtable(h);
return idmap_name_hash(h, name, len);
}
static inline struct idmap_hashent *
idmap_alloc_id(struct idmap_hashtable *h, __u32 id)
{
+ idmap_alloc_hashtable(h);
return idmap_id_hash(h, id);
}
