vfs: spread struct mount - __lookup_mnt() result

switch __lookup_mnt() to returning struct mount *; callers adjusted. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfs: spread struct mount - __lookup_mnt() result
switch __lookup_mnt() to returning struct mount *; callers adjusted. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro
1 parent 7d6fec45a5
Showing 5 changed files with 31 additions and 22 deletions Side-by-side Diff
fs/internal.h
fs/mount.h
fs/namei.c
fs/namespace.c
fs/pnode.c
@@ -15,6 +15,7 @@
 struct file_system_type;
 struct linux_binprm;
 struct path;
+struct mount;
  
 /*
  * block_dev.c
@@ -46,7 +47,6 @@
 extern int copy_mount_options(const void __user *, unsigned long *);
 extern int copy_mount_string(const void __user *, char **);
  
-extern struct vfsmount *__lookup_mnt(struct vfsmount *, struct dentry *, int);
 extern struct vfsmount *lookup_mnt(struct path *);
 extern int finish_automount(struct vfsmount *, struct path *);
  
@@ -13,4 +13,6 @@
 {
 	return mnt != mnt->mnt_parent;
 }
+
+extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *, int);
@@ -36,6 +36,7 @@
 #include <asm/uaccess.h>
  
 #include "internal.h"
+#include "mount.h"
  
 /* [Feb-1997 T. Schoebel-Theuer]
  * Fundamental changes in the pathname lookup mechanisms (namei)
@@ -884,7 +885,7 @@
 			       struct inode **inode)
 {
 	for (;;) {
-		struct vfsmount *mounted;
+		struct mount *mounted;
 		/*
 		 * Don't forget we might have a non-mountpoint managed dentry
 		 * that wants to block transit.
@@ -898,8 +899,8 @@
 		mounted = __lookup_mnt(path->mnt, path->dentry, 1);
 		if (!mounted)
 			break;
-		path->mnt = mounted;
-		path->dentry = mounted->mnt_root;
+		path->mnt = &mounted->mnt;
+		path->dentry = mounted->mnt.mnt_root;
 		nd->flags |= LOOKUP_JUMPED;
 		nd->seq = read_seqcount_begin(&path->dentry->d_seq);
 		/*
  
@@ -915,12 +916,12 @@
 static void follow_mount_rcu(struct nameidata *nd)
 {
 	while (d_mountpoint(nd->path.dentry)) {
-		struct vfsmount *mounted;
+		struct mount *mounted;
 		mounted = __lookup_mnt(nd->path.mnt, nd->path.dentry, 1);
 		if (!mounted)
 			break;
-		nd->path.mnt = mounted;
-		nd->path.dentry = mounted->mnt_root;
+		nd->path.mnt = &mounted->mnt;
+		nd->path.dentry = mounted->mnt.mnt_root;
 		nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq);
 	}
 }
@@ -464,20 +464,20 @@
  * @dir. If @dir is set return the first mount else return the last mount.
  * vfsmount_lock must be held for read or write.
  */
-struct vfsmount *__lookup_mnt(struct vfsmount *mnt, struct dentry *dentry,
+struct mount *__lookup_mnt(struct vfsmount *mnt, struct dentry *dentry,
 			      int dir)
 {
 	struct list_head *head = mount_hashtable + hash(mnt, dentry);
 	struct list_head *tmp = head;
-	struct vfsmount *p, *found = NULL;
+	struct mount *p, *found = NULL;
  
 	for (;;) {
 		tmp = dir ? tmp->next : tmp->prev;
 		p = NULL;
 		if (tmp == head)
 			break;
-		p = list_entry(tmp, struct vfsmount, mnt_hash);
-		if (p->mnt_parent == mnt && p->mnt_mountpoint == dentry) {
+		p = list_entry(tmp, struct mount, mnt.mnt_hash);
+		if (p->mnt.mnt_parent == mnt && p->mnt.mnt_mountpoint == dentry) {
 			found = p;
 			break;
 		}
  
@@ -491,13 +491,18 @@
  */
 struct vfsmount *lookup_mnt(struct path *path)
 {
-	struct vfsmount *child_mnt;
+	struct mount *child_mnt;
  
 	br_read_lock(vfsmount_lock);
-	if ((child_mnt = __lookup_mnt(path->mnt, path->dentry, 1)))
-		mntget(child_mnt);
-	br_read_unlock(vfsmount_lock);
-	return child_mnt;
+	child_mnt = __lookup_mnt(path->mnt, path->dentry, 1);
+	if (child_mnt) {
+		mnt_add_count(child_mnt, 1);
+		br_read_unlock(vfsmount_lock);
+		return &child_mnt->mnt;
+	} else {
+		br_read_unlock(vfsmount_lock);
+		return NULL;
+	}
 }
  
 static inline int check_mnt(struct vfsmount *mnt)
@@ -289,7 +289,8 @@
  */
 int propagate_mount_busy(struct vfsmount *mnt, int refcnt)
 {
-	struct vfsmount *m, *child;
+	struct vfsmount *m;
+	struct mount *child;
 	struct vfsmount *parent = mnt->mnt_parent;
 	int ret = 0;
  
@@ -307,8 +308,8 @@
 	for (m = propagation_next(parent, parent); m;
 	     		m = propagation_next(m, parent)) {
 		child = __lookup_mnt(m, mnt->mnt_mountpoint, 0);
-		if (child && list_empty(&child->mnt_mounts) &&
-		    (ret = do_refcount_check(child, 1)))
+		if (child && list_empty(&child->mnt.mnt_mounts) &&
+		    (ret = do_refcount_check(&child->mnt, 1)))
 			break;
 	}
 	return ret;
  
@@ -328,14 +329,14 @@
 	for (m = propagation_next(parent, parent); m;
 			m = propagation_next(m, parent)) {
  
-		struct vfsmount *child = __lookup_mnt(m,
+		struct mount *child = __lookup_mnt(m,
 					mnt->mnt_mountpoint, 0);
 		/*
 		 * umount the child only if the child has no
 		 * other children
 		 */
-		if (child && list_empty(&child->mnt_mounts))
-			list_move_tail(&child->mnt_hash, &mnt->mnt_hash);
+		if (child && list_empty(&child->mnt.mnt_mounts))
+			list_move_tail(&child->mnt.mnt_hash, &mnt->mnt_hash);
 	}
 }
...	...	@@ -15,6 +15,7 @@
15	15	struct file_system_type;
16	16	struct linux_binprm;
17	17	struct path;
	18	+struct mount;
18	19
19	20	/*
20	21	* block_dev.c
...	...	@@ -46,7 +47,6 @@
46	47	extern int copy_mount_options(const void __user , unsigned long );
47	48	extern int copy_mount_string(const void __user , char *);
48	49
49		-extern struct vfsmount __lookup_mnt(struct vfsmount , struct dentry *, int);
50	50	extern struct vfsmount lookup_mnt(struct path );
51	51	extern int finish_automount(struct vfsmount , struct path );
52	52
...	...	@@ -13,4 +13,6 @@
13	13	{
14	14	return mnt != mnt->mnt_parent;
15	15	}
	16	+
	17	+extern struct mount __lookup_mnt(struct vfsmount , struct dentry *, int);
...	...	@@ -36,6 +36,7 @@
36	36	#include <asm/uaccess.h>
37	37
38	38	#include "internal.h"
	39	+#include "mount.h"
39	40
40	41	/* [Feb-1997 T. Schoebel-Theuer]
41	42	* Fundamental changes in the pathname lookup mechanisms (namei)
...	...	@@ -884,7 +885,7 @@
884	885	struct inode **inode)
885	886	{
886	887	for (;;) {
887		- struct vfsmount *mounted;
	888	+ struct mount *mounted;
888	889	/*
889	890	* Don't forget we might have a non-mountpoint managed dentry
890	891	* that wants to block transit.
...	...	@@ -898,8 +899,8 @@
898	899	mounted = __lookup_mnt(path->mnt, path->dentry, 1);
899	900	if (!mounted)
900	901	break;
901		- path->mnt = mounted;
902		- path->dentry = mounted->mnt_root;
	902	+ path->mnt = &mounted->mnt;
	903	+ path->dentry = mounted->mnt.mnt_root;
903	904	nd->flags \|= LOOKUP_JUMPED;
904	905	nd->seq = read_seqcount_begin(&path->dentry->d_seq);
905	906	/*
906	907
...	...	@@ -915,12 +916,12 @@
915	916	static void follow_mount_rcu(struct nameidata *nd)
916	917	{
917	918	while (d_mountpoint(nd->path.dentry)) {
918		- struct vfsmount *mounted;
	919	+ struct mount *mounted;
919	920	mounted = __lookup_mnt(nd->path.mnt, nd->path.dentry, 1);
920	921	if (!mounted)
921	922	break;
922		- nd->path.mnt = mounted;
923		- nd->path.dentry = mounted->mnt_root;
	923	+ nd->path.mnt = &mounted->mnt;
	924	+ nd->path.dentry = mounted->mnt.mnt_root;
924	925	nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq);
925	926	}
926	927	}
...	...	@@ -464,20 +464,20 @@
464	464	* @dir. If @dir is set return the first mount else return the last mount.
465	465	* vfsmount_lock must be held for read or write.
466	466	*/
467		-struct vfsmount __lookup_mnt(struct vfsmount mnt, struct dentry *dentry,
	467	+struct mount __lookup_mnt(struct vfsmount mnt, struct dentry *dentry,
468	468	int dir)
469	469	{
470	470	struct list_head *head = mount_hashtable + hash(mnt, dentry);
471	471	struct list_head *tmp = head;
472		- struct vfsmount p, found = NULL;
	472	+ struct mount p, found = NULL;
473	473
474	474	for (;;) {
475	475	tmp = dir ? tmp->next : tmp->prev;
476	476	p = NULL;
477	477	if (tmp == head)
478	478	break;
479		- p = list_entry(tmp, struct vfsmount, mnt_hash);
480		- if (p->mnt_parent == mnt && p->mnt_mountpoint == dentry) {
	479	+ p = list_entry(tmp, struct mount, mnt.mnt_hash);
	480	+ if (p->mnt.mnt_parent == mnt && p->mnt.mnt_mountpoint == dentry) {
481	481	found = p;
482	482	break;
483	483	}
484	484
...	...	@@ -491,13 +491,18 @@
491	491	*/
492	492	struct vfsmount lookup_mnt(struct path path)
493	493	{
494		- struct vfsmount *child_mnt;
	494	+ struct mount *child_mnt;
495	495
496	496	br_read_lock(vfsmount_lock);
497		- if ((child_mnt = __lookup_mnt(path->mnt, path->dentry, 1)))
498		- mntget(child_mnt);
499		- br_read_unlock(vfsmount_lock);
500		- return child_mnt;
	497	+ child_mnt = __lookup_mnt(path->mnt, path->dentry, 1);
	498	+ if (child_mnt) {
	499	+ mnt_add_count(child_mnt, 1);
	500	+ br_read_unlock(vfsmount_lock);
	501	+ return &child_mnt->mnt;
	502	+ } else {
	503	+ br_read_unlock(vfsmount_lock);
	504	+ return NULL;
	505	+ }
501	506	}
502	507
503	508	static inline int check_mnt(struct vfsmount *mnt)
...	...	@@ -289,7 +289,8 @@
289	289	*/
290	290	int propagate_mount_busy(struct vfsmount *mnt, int refcnt)
291	291	{
292		- struct vfsmount m, child;
	292	+ struct vfsmount *m;
	293	+ struct mount *child;
293	294	struct vfsmount *parent = mnt->mnt_parent;
294	295	int ret = 0;
295	296
...	...	@@ -307,8 +308,8 @@
307	308	for (m = propagation_next(parent, parent); m;
308	309	m = propagation_next(m, parent)) {
309	310	child = __lookup_mnt(m, mnt->mnt_mountpoint, 0);
310		- if (child && list_empty(&child->mnt_mounts) &&
311		- (ret = do_refcount_check(child, 1)))
	311	+ if (child && list_empty(&child->mnt.mnt_mounts) &&
	312	+ (ret = do_refcount_check(&child->mnt, 1)))
312	313	break;
313	314	}
314	315	return ret;
315	316
...	...	@@ -328,14 +329,14 @@
328	329	for (m = propagation_next(parent, parent); m;
329	330	m = propagation_next(m, parent)) {
330	331
331		- struct vfsmount *child = __lookup_mnt(m,
	332	+ struct mount *child = __lookup_mnt(m,
332	333	mnt->mnt_mountpoint, 0);
333	334	/*
334	335	* umount the child only if the child has no
335	336	* other children
336	337	*/
337		- if (child && list_empty(&child->mnt_mounts))
338		- list_move_tail(&child->mnt_hash, &mnt->mnt_hash);
	338	+ if (child && list_empty(&child->mnt.mnt_mounts))
	339	+ list_move_tail(&child->mnt.mnt_hash, &mnt->mnt_hash);
339	340	}
340	341	}
341	342