propagate_mnt(): get rid of globals
TBH, I'm not sure it makes the things better, but...
Fixed a stale comment, while we are at it - propagate_mnt() does *not*
use ->mnt_list for linkage and it does not attach the secondaries to
the original - they go into the caller-supplied list. It had gone
stale before the entire thing got merged into the tree...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/pnode.c b/fs/pnode.c
index b54f7ca..dacb7f5 100644
--- a/fs/pnode.c
+++ b/fs/pnode.c
@@ -214,25 +214,28 @@ static struct mount *next_group(struct mount *m, struct mount *origin)
}
}
-/* all accesses are serialized by namespace_sem */
-static struct mount *last_dest, *first_source, *last_source;
-static struct hlist_head *list;
+struct propagate_mnt_context {
+ struct mountpoint *dest_mp;
+ struct hlist_head *list;
+ struct mount *last_dest, *source, *last_source;
+};
-static int propagate_one(struct mount *m, struct mountpoint *dest_mp)
+static int propagate_one(struct mount *m, struct propagate_mnt_context *ctx)
{
- struct mount *child;
+ struct mount *last_source = ctx->last_source;
+ struct mount *copy;
int type;
/* skip ones added by this propagate_mnt() */
if (IS_MNT_NEW(m))
return 0;
/* skip if mountpoint isn't visible in m */
- if (!is_subdir(dest_mp->m_dentry, m->mnt.mnt_root))
+ if (!is_subdir(ctx->dest_mp->m_dentry, m->mnt.mnt_root))
return 0;
/* skip if m is in the anon_ns */
if (is_anon_ns(m->mnt_ns))
return 0;
- if (peers(m, last_dest)) {
+ if (peers(m, ctx->last_dest)) {
type = CL_MAKE_SHARED;
} else {
struct mount *n, *p;
@@ -244,7 +247,7 @@ static int propagate_one(struct mount *m, struct mountpoint *dest_mp)
}
do {
struct mount *parent = last_source->mnt_parent;
- if (peers(last_source, first_source))
+ if (peers(last_source, ctx->source))
break;
done = parent->mnt_master == p;
if (done && peers(n, parent))
@@ -258,18 +261,18 @@ static int propagate_one(struct mount *m, struct mountpoint *dest_mp)
type |= CL_MAKE_SHARED;
}
- child = copy_tree(last_source, last_source->mnt.mnt_root, type);
- if (IS_ERR(child))
- return PTR_ERR(child);
+ copy = copy_tree(last_source, last_source->mnt.mnt_root, type);
+ if (IS_ERR(copy))
+ return PTR_ERR(copy);
read_seqlock_excl(&mount_lock);
- mnt_set_mountpoint(m, dest_mp, child);
+ mnt_set_mountpoint(m, ctx->dest_mp, copy);
read_sequnlock_excl(&mount_lock);
if (m->mnt_master)
SET_MNT_MARK(m->mnt_master);
- last_dest = m;
- last_source = child;
- hlist_add_head(&child->mnt_hash, list);
- return count_mounts(m->mnt_ns, child);
+ ctx->last_dest = m;
+ ctx->last_source = copy;
+ hlist_add_head(©->mnt_hash, ctx->list);
+ return count_mounts(m->mnt_ns, copy);
}
/*
@@ -277,35 +280,33 @@ static int propagate_one(struct mount *m, struct mountpoint *dest_mp)
* dentry 'dest_dentry'. And propagate that mount to
* all the peer and slave mounts of 'dest_mnt'.
* Link all the new mounts into a propagation tree headed at
- * source_mnt. Also link all the new mounts using ->mnt_list
- * headed at source_mnt's ->mnt_list
+ * source_mnt. Roots of all copies placed into 'tree_list',
+ * linked by ->mnt_hash.
*
* @dest_mnt: destination mount.
* @dest_dentry: destination dentry.
* @source_mnt: source mount.
- * @tree_list : list of heads of trees to be attached.
+ * @tree_list : list of trees to be attached.
*/
int propagate_mnt(struct mount *dest_mnt, struct mountpoint *dest_mp,
struct mount *source_mnt, struct hlist_head *tree_list)
{
struct mount *m, *n;
int ret = 0;
+ struct propagate_mnt_context ctx = {
+ .source = source_mnt,
+ .dest_mp = dest_mp,
+ .list = tree_list,
+ .last_source = source_mnt,
+ .last_dest = dest_mnt,
+ };
- /*
- * we don't want to bother passing tons of arguments to
- * propagate_one(); everything is serialized by namespace_sem,
- * so globals will do just fine.
- */
- last_dest = dest_mnt;
- first_source = source_mnt;
- last_source = source_mnt;
- list = tree_list;
if (dest_mnt->mnt_master)
SET_MNT_MARK(dest_mnt->mnt_master);
/* all peers of dest_mnt, except dest_mnt itself */
for (n = next_peer(dest_mnt); n != dest_mnt; n = next_peer(n)) {
- ret = propagate_one(n, dest_mp);
+ ret = propagate_one(n, &ctx);
if (ret)
goto out;
}
@@ -316,7 +317,7 @@ int propagate_mnt(struct mount *dest_mnt, struct mountpoint *dest_mp,
/* everything in that slave group */
n = m;
do {
- ret = propagate_one(n, dest_mp);
+ ret = propagate_one(n, &ctx);
if (ret)
goto out;
n = next_peer(n);
