NFS: Add a helper to remove case-insensitive aliases

When dealing with case insensitive names, the client has no idea how the
server performs the mapping, so cannot collapse the dentries into a
single representative. So both rename and unlink need to deal with the
fact that there could be several dentries representing the file, and
have to somehow force them to be revalidated. Use d_prune_aliases() as a
big hammer approach.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index a691a1e364a7907c9d36e6d481ad857838608158..d2a58f7a73a616f794b15413dc0ad6cffdcb0154 100644 (file)
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1819,6 +1819,14 @@ out:
 }
 EXPORT_SYMBOL_GPL(nfs_lookup);
 
+void nfs_d_prune_case_insensitive_aliases(struct inode *inode)
+{
+       /* Case insensitive server? Revalidate dentries */
+       if (inode && nfs_server_capable(inode, NFS_CAP_CASE_INSENSITIVE))
+               d_prune_aliases(inode);
+}
+EXPORT_SYMBOL_GPL(nfs_d_prune_case_insensitive_aliases);
+
 #if IS_ENABLED(CONFIG_NFS_V4)
 static int nfs4_lookup_revalidate(struct dentry *, unsigned int);
 
@@ -2199,8 +2207,10 @@ static void nfs_dentry_remove_handle_error(struct inode *dir,
        switch (error) {
        case -ENOENT:
                d_delete(dentry);
-               fallthrough;
+               nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
+               break;
        case 0:
+               nfs_d_prune_case_insensitive_aliases(d_inode(dentry));
                nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
        }
 }

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 12f6acb483bbd60b002121bc9a56bbcbc5f16b52..2de7c56a1fbedb2e1e9077c7ba5bebf5992a0954 100644 (file)
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -373,6 +373,7 @@ extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
 extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
                                           struct shrink_control *sc);
 struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
+void nfs_d_prune_case_insensitive_aliases(struct inode *inode);
 int nfs_create(struct user_namespace *, struct inode *, struct dentry *,
               umode_t, bool);
 int nfs_mkdir(struct user_namespace *, struct inode *, struct dentry *,

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index a6d7472058adb777bdbaf8f663d2bf67b847f5b0..7df2eb74025ff54c0448b32cb0fd11db617b95c7 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -4670,8 +4670,10 @@ static void nfs4_proc_unlink_setup(struct rpc_message *msg,
 
        nfs_fattr_init(res->dir_attr);
 
-       if (inode)
+       if (inode) {
                nfs4_inode_return_delegation(inode);
+               nfs_d_prune_case_insensitive_aliases(inode);
+       }
 }
 
 static void nfs4_proc_unlink_rpc_prepare(struct rpc_task *task, struct nfs_unlinkdata *data)
@@ -4737,6 +4739,7 @@ static int nfs4_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
                return 0;
 
        if (task->tk_status == 0) {
+               nfs_d_prune_case_insensitive_aliases(d_inode(data->old_dentry));
                if (new_dir != old_dir) {
                        /* Note: If we moved a directory, nlink will change */
                        nfs4_update_changeattr(old_dir, &res->old_cinfo,