NFS: Separate tracking of file nlinks cache validity from the mode/uid/gid

Rename can cause us to revalidate the access cache, so lets track the
nlinks separately from the mode/uid/gid.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/dir.c

@@ -1711,7 +1711,7 @@ static void nfs_drop_nlink(struct inode *inode)
 	NFS_I(inode)->attr_gencount = nfs_inc_attr_generation_counter();
 	nfs_set_cache_invalid(
 		inode, NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_CTIME |
-			       NFS_INO_INVALID_OTHER | NFS_INO_REVAL_FORCED);
+			       NFS_INO_INVALID_NLINK | NFS_INO_REVAL_FORCED);
 	spin_unlock(&inode->i_lock);
 }
 

fs/nfs/inode.c

@@ -538,7 +538,7 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, st
 		if (fattr->valid & NFS_ATTR_FATTR_NLINK)
 			set_nlink(inode, fattr->nlink);
 		else if (nfs_server_capable(inode, NFS_CAP_NLINK))
-			nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
+			nfs_set_cache_invalid(inode, NFS_INO_INVALID_NLINK);
 		if (fattr->valid & NFS_ATTR_FATTR_OWNER)
 			inode->i_uid = fattr->uid;
 		else if (nfs_server_capable(inode, NFS_CAP_OWNER))
@@ -801,8 +801,10 @@ static u32 nfs_get_valid_attrmask(struct inode *inode)
 		reply_mask |= STATX_MTIME;
 	if (!(cache_validity & NFS_INO_INVALID_SIZE))
 		reply_mask |= STATX_SIZE;
+	if (!(cache_validity & NFS_INO_INVALID_NLINK))
+		reply_mask |= STATX_NLINK;
 	if (!(cache_validity & NFS_INO_INVALID_OTHER))
-		reply_mask |= STATX_UID | STATX_GID | STATX_MODE | STATX_NLINK;
+		reply_mask |= STATX_UID | STATX_GID | STATX_MODE;
 	if (!(cache_validity & NFS_INO_INVALID_BLOCKS))
 		reply_mask |= STATX_BLOCKS;
 	return reply_mask;
@@ -868,7 +870,9 @@ int nfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
 		do_update |= cache_validity & NFS_INO_INVALID_MTIME;
 	if (request_mask & STATX_SIZE)
 		do_update |= cache_validity & NFS_INO_INVALID_SIZE;
-	if (request_mask & (STATX_UID | STATX_GID | STATX_MODE | STATX_NLINK))
+	if (request_mask & STATX_NLINK)
+		do_update |= cache_validity & NFS_INO_INVALID_NLINK;
+	if (request_mask & (STATX_UID | STATX_GID | STATX_MODE))
 		do_update |= cache_validity & NFS_INO_INVALID_OTHER;
 	if (request_mask & STATX_BLOCKS)
 		do_update |= cache_validity & NFS_INO_INVALID_BLOCKS;
@@ -1518,7 +1522,7 @@ static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fat
 
 	/* Has the link count changed? */
 	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
-		invalid |= NFS_INO_INVALID_OTHER;
+		invalid |= NFS_INO_INVALID_NLINK;
 
 	ts = inode->i_atime;
 	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec64_equal(&ts, &fattr->atime))
@@ -1942,6 +1946,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 					| NFS_INO_INVALID_MTIME
 					| NFS_INO_INVALID_SIZE
 					| NFS_INO_INVALID_BLOCKS
+					| NFS_INO_INVALID_NLINK
 					| NFS_INO_INVALID_OTHER;
 				if (S_ISDIR(inode->i_mode))
 					nfs_force_lookup_revalidate(inode);
@@ -2074,7 +2079,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 		}
 	} else if (server->caps & NFS_CAP_NLINK) {
 		nfsi->cache_validity |= save_cache_validity &
-				(NFS_INO_INVALID_OTHER
+				(NFS_INO_INVALID_NLINK
 				| NFS_INO_REVAL_FORCED);
 		cache_revalidated = false;
 	}

fs/nfs/nfs4proc.c

@@ -1167,14 +1167,14 @@ int nfs4_call_sync(struct rpc_clnt *clnt,
 static void
 nfs4_inc_nlink_locked(struct inode *inode)
 {
-	nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
+	nfs_set_cache_invalid(inode, NFS_INO_INVALID_NLINK);
 	inc_nlink(inode);
 }
 
 static void
 nfs4_dec_nlink_locked(struct inode *inode)
 {
-	nfs_set_cache_invalid(inode, NFS_INO_INVALID_OTHER);
+	nfs_set_cache_invalid(inode, NFS_INO_INVALID_NLINK);
 	drop_nlink(inode);
 }
 
@@ -4717,11 +4717,11 @@ static int nfs4_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
 			/* Note: If we moved a directory, nlink will change */
 			nfs4_update_changeattr(old_dir, &res->old_cinfo,
 					res->old_fattr->time_start,
-					NFS_INO_INVALID_OTHER |
+					NFS_INO_INVALID_NLINK |
 					    NFS_INO_INVALID_DATA);
 			nfs4_update_changeattr(new_dir, &res->new_cinfo,
 					res->new_fattr->time_start,
-					NFS_INO_INVALID_OTHER |
+					NFS_INO_INVALID_NLINK |
 					    NFS_INO_INVALID_DATA);
 		} else
 			nfs4_update_changeattr(old_dir, &res->old_cinfo,
@@ -5433,8 +5433,9 @@ static void nfs4_bitmask_set(__u32 bitmask[NFS4_BITMASK_SZ], const __u32 *src,
 		bitmask[1] |= FATTR4_WORD1_TIME_ACCESS;
 	if (cache_validity & NFS_INO_INVALID_OTHER)
 		bitmask[1] |= FATTR4_WORD1_MODE | FATTR4_WORD1_OWNER |
-				FATTR4_WORD1_OWNER_GROUP |
-				FATTR4_WORD1_NUMLINKS;
+				FATTR4_WORD1_OWNER_GROUP;
+	if (cache_validity & NFS_INO_INVALID_NLINK)
+		bitmask[1] |= FATTR4_WORD1_NUMLINKS;
 	if (label && label->len && cache_validity & NFS_INO_INVALID_LABEL)
 		bitmask[2] |= FATTR4_WORD2_SECURITY_LABEL;
 	if (cache_validity & NFS_INO_INVALID_CTIME)

fs/nfs/nfstrace.h

@@ -48,6 +48,7 @@ TRACE_DEFINE_ENUM(NFS_INO_INVALID_OTHER);
 TRACE_DEFINE_ENUM(NFS_INO_DATA_INVAL_DEFER);
 TRACE_DEFINE_ENUM(NFS_INO_INVALID_BLOCKS);
 TRACE_DEFINE_ENUM(NFS_INO_INVALID_XATTR);
+TRACE_DEFINE_ENUM(NFS_INO_INVALID_NLINK);
 
 #define nfs_show_cache_validity(v) \
 	__print_flags(v, "|", \
@@ -65,7 +66,8 @@ TRACE_DEFINE_ENUM(NFS_INO_INVALID_XATTR);
 			{ NFS_INO_INVALID_OTHER, "INVALID_OTHER" }, \
 			{ NFS_INO_DATA_INVAL_DEFER, "DATA_INVAL_DEFER" }, \
 			{ NFS_INO_INVALID_BLOCKS, "INVALID_BLOCKS" }, \
-			{ NFS_INO_INVALID_XATTR, "INVALID_XATTR" })
+			{ NFS_INO_INVALID_XATTR, "INVALID_XATTR" }, \
+			{ NFS_INO_INVALID_NLINK, "INVALID_NLINK" })
 
 TRACE_DEFINE_ENUM(NFS_INO_ADVISE_RDPLUS);
 TRACE_DEFINE_ENUM(NFS_INO_STALE);

include/linux/nfs_fs.h

@@ -246,11 +246,13 @@ struct nfs4_copy_state {
 				BIT(13)		/* Deferred cache invalidation */
 #define NFS_INO_INVALID_BLOCKS	BIT(14)         /* cached blocks are invalid */
 #define NFS_INO_INVALID_XATTR	BIT(15)		/* xattrs are invalid */
+#define NFS_INO_INVALID_NLINK	BIT(16)		/* cached nlinks is invalid */
 
 #define NFS_INO_INVALID_ATTR	(NFS_INO_INVALID_CHANGE \
 		| NFS_INO_INVALID_CTIME \
 		| NFS_INO_INVALID_MTIME \
 		| NFS_INO_INVALID_SIZE \
+		| NFS_INO_INVALID_NLINK \
 		| NFS_INO_INVALID_OTHER)	/* inode metadata is invalid */
 
 /*