nfsd: nfsd_file cache entries should be per net namespace

Ensure that we can safely clear out the file cache entries when the
nfs server is shut down on a container. Otherwise, the file cache
may end up pinning the mounts.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
Trond Myklebust 2019-09-02 13:02:55 -04:00 committed by J. Bruce Fields
parent 2b86e3aaf9
commit 5e113224c1
4 changed files with 25 additions and 14 deletions

View File

@ -240,7 +240,7 @@ static void expkey_flush(void)
* destroyed while we're in the middle of flushing.
*/
mutex_lock(&nfsd_mutex);
nfsd_file_cache_purge();
nfsd_file_cache_purge(current->nsproxy->net_ns);
mutex_unlock(&nfsd_mutex);
}

View File

@ -16,6 +16,7 @@
#include "vfs.h"
#include "nfsd.h"
#include "nfsfh.h"
#include "netns.h"
#include "filecache.h"
#include "trace.h"
@ -167,7 +168,8 @@ nfsd_file_mark_find_or_create(struct nfsd_file *nf)
}
static struct nfsd_file *
nfsd_file_alloc(struct inode *inode, unsigned int may, unsigned int hashval)
nfsd_file_alloc(struct inode *inode, unsigned int may, unsigned int hashval,
struct net *net)
{
struct nfsd_file *nf;
@ -177,6 +179,7 @@ nfsd_file_alloc(struct inode *inode, unsigned int may, unsigned int hashval)
INIT_LIST_HEAD(&nf->nf_lru);
nf->nf_file = NULL;
nf->nf_cred = get_current_cred();
nf->nf_net = net;
nf->nf_flags = 0;
nf->nf_inode = inode;
nf->nf_hashval = hashval;
@ -607,10 +610,11 @@ out_err:
* Note this can deadlock with nfsd_file_lru_cb.
*/
void
nfsd_file_cache_purge(void)
nfsd_file_cache_purge(struct net *net)
{
unsigned int i;
struct nfsd_file *nf;
struct hlist_node *next;
LIST_HEAD(dispose);
bool del;
@ -618,10 +622,12 @@ nfsd_file_cache_purge(void)
return;
for (i = 0; i < NFSD_FILE_HASH_SIZE; i++) {
spin_lock(&nfsd_file_hashtbl[i].nfb_lock);
while(!hlist_empty(&nfsd_file_hashtbl[i].nfb_head)) {
nf = hlist_entry(nfsd_file_hashtbl[i].nfb_head.first,
struct nfsd_file, nf_node);
struct nfsd_fcache_bucket *nfb = &nfsd_file_hashtbl[i];
spin_lock(&nfb->nfb_lock);
hlist_for_each_entry_safe(nf, next, &nfb->nfb_head, nf_node) {
if (net && nf->nf_net != net)
continue;
del = nfsd_file_unhash_and_release_locked(nf, &dispose);
/*
@ -630,7 +636,7 @@ nfsd_file_cache_purge(void)
*/
WARN_ON_ONCE(!del);
}
spin_unlock(&nfsd_file_hashtbl[i].nfb_lock);
spin_unlock(&nfb->nfb_lock);
nfsd_file_dispose_list(&dispose);
}
}
@ -649,7 +655,7 @@ nfsd_file_cache_shutdown(void)
* calling nfsd_file_cache_purge
*/
cancel_delayed_work_sync(&nfsd_filecache_laundrette);
nfsd_file_cache_purge();
nfsd_file_cache_purge(NULL);
list_lru_destroy(&nfsd_file_lru);
rcu_barrier();
fsnotify_put_group(nfsd_file_fsnotify_group);
@ -685,7 +691,7 @@ nfsd_match_cred(const struct cred *c1, const struct cred *c2)
static struct nfsd_file *
nfsd_file_find_locked(struct inode *inode, unsigned int may_flags,
unsigned int hashval)
unsigned int hashval, struct net *net)
{
struct nfsd_file *nf;
unsigned char need = may_flags & NFSD_FILE_MAY_MASK;
@ -696,6 +702,8 @@ nfsd_file_find_locked(struct inode *inode, unsigned int may_flags,
continue;
if (nf->nf_inode != inode)
continue;
if (nf->nf_net != net)
continue;
if (!nfsd_match_cred(nf->nf_cred, current_cred()))
continue;
if (nfsd_file_get(nf) != NULL)
@ -738,6 +746,7 @@ nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
unsigned int may_flags, struct nfsd_file **pnf)
{
__be32 status;
struct net *net = SVC_NET(rqstp);
struct nfsd_file *nf, *new;
struct inode *inode;
unsigned int hashval;
@ -752,12 +761,12 @@ nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
hashval = (unsigned int)hash_long(inode->i_ino, NFSD_FILE_HASH_BITS);
retry:
rcu_read_lock();
nf = nfsd_file_find_locked(inode, may_flags, hashval);
nf = nfsd_file_find_locked(inode, may_flags, hashval, net);
rcu_read_unlock();
if (nf)
goto wait_for_construction;
new = nfsd_file_alloc(inode, may_flags, hashval);
new = nfsd_file_alloc(inode, may_flags, hashval, net);
if (!new) {
trace_nfsd_file_acquire(rqstp, hashval, inode, may_flags,
NULL, nfserr_jukebox);
@ -765,7 +774,7 @@ retry:
}
spin_lock(&nfsd_file_hashtbl[hashval].nfb_lock);
nf = nfsd_file_find_locked(inode, may_flags, hashval);
nf = nfsd_file_find_locked(inode, may_flags, hashval, net);
if (nf == NULL)
goto open_file;
spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock);

View File

@ -34,6 +34,7 @@ struct nfsd_file {
struct rcu_head nf_rcu;
struct file *nf_file;
const struct cred *nf_cred;
struct net *nf_net;
#define NFSD_FILE_HASHED (0)
#define NFSD_FILE_PENDING (1)
#define NFSD_FILE_BREAK_READ (2)
@ -48,7 +49,7 @@ struct nfsd_file {
};
int nfsd_file_cache_init(void);
void nfsd_file_cache_purge(void);
void nfsd_file_cache_purge(struct net *);
void nfsd_file_cache_shutdown(void);
void nfsd_file_put(struct nfsd_file *nf);
struct nfsd_file *nfsd_file_get(struct nfsd_file *nf);

View File

@ -387,6 +387,7 @@ static void nfsd_shutdown_net(struct net *net)
{
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
nfsd_file_cache_purge(net);
nfs4_state_shutdown_net(net);
if (nn->lockd_up) {
lockd_down(net);