5.10-stable review patch. If anyone has any objections, please let me know.
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From: J. Bruce Fields bfields@redhat.com
[ Upstream commit a0ce48375a367222989c2618fe68bf34db8c7bb7 ]
It's unusual but possible for multiple filehandles to point to the same file. In that case, we may end up with multiple nfs4_files referencing the same inode.
For delegation purposes it will turn out to be useful to flag those cases.
Signed-off-by: J. Bruce Fields bfields@redhat.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/nfs4state.c | 37 ++++++++++++++++++++++++++++--------- fs/nfsd/state.h | 2 ++ 2 files changed, 30 insertions(+), 9 deletions(-)
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 8d2d6e90bfc5e..89d5669ce1463 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4120,6 +4120,8 @@ static void nfsd4_init_file(struct svc_fh *fh, unsigned int hashval, fp->fi_share_deny = 0; memset(fp->fi_fds, 0, sizeof(fp->fi_fds)); memset(fp->fi_access, 0, sizeof(fp->fi_access)); + fp->fi_aliased = false; + fp->fi_inode = d_inode(fh->fh_dentry); #ifdef CONFIG_NFSD_PNFS INIT_LIST_HEAD(&fp->fi_lo_states); atomic_set(&fp->fi_lo_recalls, 0); @@ -4472,6 +4474,31 @@ find_file_locked(struct svc_fh *fh, unsigned int hashval) return NULL; }
+static struct nfs4_file *insert_file(struct nfs4_file *new, struct svc_fh *fh, + unsigned int hashval) +{ + struct nfs4_file *fp; + struct nfs4_file *ret = NULL; + bool alias_found = false; + + spin_lock(&state_lock); + hlist_for_each_entry_rcu(fp, &file_hashtbl[hashval], fi_hash, + lockdep_is_held(&state_lock)) { + if (fh_match(&fp->fi_fhandle, &fh->fh_handle)) { + if (refcount_inc_not_zero(&fp->fi_ref)) + ret = fp; + } else if (d_inode(fh->fh_dentry) == fp->fi_inode) + fp->fi_aliased = alias_found = true; + } + if (likely(ret == NULL)) { + nfsd4_init_file(fh, hashval, new); + new->fi_aliased = alias_found; + ret = new; + } + spin_unlock(&state_lock); + return ret; +} + static struct nfs4_file * find_file(struct svc_fh *fh) { struct nfs4_file *fp; @@ -4495,15 +4522,7 @@ find_or_add_file(struct nfs4_file *new, struct svc_fh *fh) if (fp) return fp;
- spin_lock(&state_lock); - fp = find_file_locked(fh, hashval); - if (likely(fp == NULL)) { - nfsd4_init_file(fh, hashval, new); - fp = new; - } - spin_unlock(&state_lock); - - return fp; + return insert_file(new, fh, hashval); }
/* diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index 61a2d95d79233..e73bdbb1634ab 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -516,6 +516,8 @@ struct nfs4_clnt_odstate { */ struct nfs4_file { refcount_t fi_ref; + struct inode * fi_inode; + bool fi_aliased; spinlock_t fi_lock; struct hlist_node fi_hash; /* hash on fi_fhandle */ struct list_head fi_stateids;