From 5e113224c17e2fb156b785ddbbc48a0209fddb0c Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 2 Sep 2019 13:02:55 -0400 Subject: [PATCH] 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 Signed-off-by: J. Bruce Fields --- fs/nfsd/export.c | 2 +- fs/nfsd/filecache.c | 33 +++++++++++++++++++++------------ fs/nfsd/filecache.h | 3 ++- fs/nfsd/nfssvc.c | 1 + 4 files changed, 25 insertions(+), 14 deletions(-) diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c index 052fac64b578..15422c951fd1 100644 --- a/fs/nfsd/export.c +++ b/fs/nfsd/export.c @@ -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); } diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 2e1a972231e5..da9e790a055e 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -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); diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h index 0c0c67166b87..851d9abf54c2 100644 --- a/fs/nfsd/filecache.h +++ b/fs/nfsd/filecache.h @@ -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); diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index d02712ca2685..b944553c6927 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -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);