svn commit: r326998 - head/sys/fs/tmpfs

[John Baldwin]

Author: jhb
Date: Tue Dec 19 20:19:07 2017
New Revision: 326998
URL: https://svnweb.freebsd.org/changeset/base/326998

Log:
  Update tmpfs link count handling for ino64.
  
  Add a new TMPFS_LINK_MAX to use in place of LINK_MAX for link overflow
  checks and pathconf() reporting.  Rather than storing a full 64-bit
  link count, just use a plain int and use INT_MAX as TMPFS_LINK_MAX.
  
  Discussed with:	bde
  Reviewed by:	kib (part of a larger patch)
  Sponsored by:	Chelsio Communications

Modified:
  head/sys/fs/tmpfs/tmpfs.h
  head/sys/fs/tmpfs/tmpfs_subr.c
  head/sys/fs/tmpfs/tmpfs_vnops.c

Modified: head/sys/fs/tmpfs/tmpfs.h
==============================================================================
--- head/sys/fs/tmpfs/tmpfs.h	Tue Dec 19 20:17:07 2017	(r326997)
+++ head/sys/fs/tmpfs/tmpfs.h	Tue Dec 19 20:19:07 2017	(r326998)
@@ -188,8 +188,8 @@ struct tmpfs_node {
 	uid_t			tn_uid;		/* (v) */
 	gid_t			tn_gid;		/* (v) */
 	mode_t			tn_mode;	/* (v) */
+	int			tn_links;	/* (v) */
 	u_long			tn_flags;	/* (v) */
-	nlink_t			tn_links;	/* (v) */
 	struct timespec		tn_atime;	/* (vi) */
 	struct timespec		tn_mtime;	/* (vi) */
 	struct timespec		tn_ctime;	/* (vi) */
@@ -296,6 +296,8 @@ LIST_HEAD(tmpfs_node_list, tmpfs_node);
 #define tn_link tn_spec.tn_link
 #define tn_reg tn_spec.tn_reg
 #define tn_fifo tn_spec.tn_fifo
+
+#define	TMPFS_LINK_MAX INT_MAX
 
 #define TMPFS_NODE_LOCK(node) mtx_lock(&(node)->tn_interlock)
 #define TMPFS_NODE_UNLOCK(node) mtx_unlock(&(node)->tn_interlock)

Modified: head/sys/fs/tmpfs/tmpfs_subr.c
==============================================================================
--- head/sys/fs/tmpfs/tmpfs_subr.c	Tue Dec 19 20:17:07 2017	(r326997)
+++ head/sys/fs/tmpfs/tmpfs_subr.c	Tue Dec 19 20:19:07 2017	(r326998)
@@ -739,8 +739,8 @@ tmpfs_alloc_file(struct vnode *dvp, struct vnode **vpp
 	if (vap->va_type == VDIR) {
 		/* Ensure that we do not overflow the maximum number of links
 		 * imposed by the system. */
-		MPASS(dnode->tn_links <= LINK_MAX);
-		if (dnode->tn_links == LINK_MAX) {
+		MPASS(dnode->tn_links <= TMPFS_LINK_MAX);
+		if (dnode->tn_links == TMPFS_LINK_MAX) {
 			return (EMLINK);
 		}
 

Modified: head/sys/fs/tmpfs/tmpfs_vnops.c
==============================================================================
--- head/sys/fs/tmpfs/tmpfs_vnops.c	Tue Dec 19 20:17:07 2017	(r326997)
+++ head/sys/fs/tmpfs/tmpfs_vnops.c	Tue Dec 19 20:19:07 2017	(r326998)
@@ -41,6 +41,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/dirent.h>
 #include <sys/fcntl.h>
+#include <sys/limits.h>
 #include <sys/lockf.h>
 #include <sys/lock.h>
 #include <sys/mount.h>
@@ -618,8 +619,8 @@ tmpfs_link(struct vop_link_args *v)
 
 	/* Ensure that we do not overflow the maximum number of links imposed
 	 * by the system. */
-	MPASS(node->tn_links <= LINK_MAX);
-	if (node->tn_links == LINK_MAX) {
+	MPASS(node->tn_links <= TMPFS_LINK_MAX);
+	if (node->tn_links == TMPFS_LINK_MAX) {
 		error = EMLINK;
 		goto out;
 	}
@@ -1349,7 +1350,7 @@ tmpfs_pathconf(struct vop_pathconf_args *v)
 
 	switch (name) {
 	case _PC_LINK_MAX:
-		*retval = LINK_MAX;
+		*retval = TMPFS_LINK_MAX;
 		break;
 
 	case _PC_NAME_MAX: