Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Fun set of conflict resolutions here...

For the mac80211 stuff, these were fortunately just parallel
adds.  Trivially resolved.

In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.

In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.

The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.

The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:

====================

    Due to bug fixes found by the syzkaller bot and taken into the for-rc
    branch after development for the 4.17 merge window had already started
    being taken into the for-next branch, there were fairly non-trivial
    merge issues that would need to be resolved between the for-rc branch
    and the for-next branch.  This merge resolves those conflicts and
    provides a unified base upon which ongoing development for 4.17 can
    be based.

    Conflicts:
            drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f9524
            (IB/mlx5: Fix cleanup order on unload) added to for-rc and
            commit b5ca15ad7e61 (IB/mlx5: Add proper representors support)
            add as part of the devel cycle both needed to modify the
            init/de-init functions used by mlx5.  To support the new
            representors, the new functions added by the cleanup patch
            needed to be made non-static, and the init/de-init list
            added by the representors patch needed to be modified to
            match the init/de-init list changes made by the cleanup
            patch.
    Updates:
            drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
            prototypes added by representors patch to reflect new function
            names as changed by cleanup patch
            drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
            stage list to match new order from cleanup patch
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 40 insertions, 18 deletions

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index fcd97b783fa1..3b1bd469accd 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -669,38 +669,59 @@ struct inode *ovl_lookup_inode(struct super_block *sb, struct dentry *real,
 	return inode;
 }
 
+/*
+ * Does overlay inode need to be hashed by lower inode?
+ */
+static bool ovl_hash_bylower(struct super_block *sb, struct dentry *upper,
+			     struct dentry *lower, struct dentry *index)
+{
+	struct ovl_fs *ofs = sb->s_fs_info;
+
+	/* No, if pure upper */
+	if (!lower)
+		return false;
+
+	/* Yes, if already indexed */
+	if (index)
+		return true;
+
+	/* Yes, if won't be copied up */
+	if (!ofs->upper_mnt)
+		return true;
+
+	/* No, if lower hardlink is or will be broken on copy up */
+	if ((upper || !ovl_indexdir(sb)) &&
+	    !d_is_dir(lower) && d_inode(lower)->i_nlink > 1)
+		return false;
+
+	/* No, if non-indexed upper with NFS export */
+	if (sb->s_export_op && upper)
+		return false;
+
+	/* Otherwise, hash by lower inode for fsnotify */
+	return true;
+}
+
 struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry,
 			    struct dentry *lowerdentry, struct dentry *index,
 			    unsigned int numlower)
 {
-	struct ovl_fs *ofs = sb->s_fs_info;
 	struct inode *realinode = upperdentry ? d_inode(upperdentry) : NULL;
 	struct inode *inode;
-	/* Already indexed or could be indexed on copy up? */
-	bool indexed = (index || (ovl_indexdir(sb) && !upperdentry));
-	struct dentry *origin = indexed ? lowerdentry : NULL;
+	bool bylower = ovl_hash_bylower(sb, upperdentry, lowerdentry, index);
 	bool is_dir;
 
-	if (WARN_ON(upperdentry && indexed && !lowerdentry))
-		return ERR_PTR(-EIO);
-
 	if (!realinode)
 		realinode = d_inode(lowerdentry);
 
 	/*
-	 * Copy up origin (lower) may exist for non-indexed non-dir upper, but
-	 * we must not use lower as hash key in that case.
-	 * Hash non-dir that is or could be indexed by origin inode.
-	 * Hash dir that is or could be merged by origin inode.
-	 * Hash pure upper and non-indexed non-dir by upper inode.
-	 * Hash non-indexed dir by upper inode for NFS export.
+	 * Copy up origin (lower) may exist for non-indexed upper, but we must
+	 * not use lower as hash key if this is a broken hardlink.
 	 */
 	is_dir = S_ISDIR(realinode->i_mode);
-	if (is_dir && (indexed || !sb->s_export_op || !ofs->upper_mnt))
-		origin = lowerdentry;
-
-	if (upperdentry || origin) {
-		struct inode *key = d_inode(origin ?: upperdentry);
+	if (upperdentry || bylower) {
+		struct inode *key = d_inode(bylower ? lowerdentry :
+						      upperdentry);
 		unsigned int nlink = is_dir ? 1 : realinode->i_nlink;
 
 		inode = iget5_locked(sb, (unsigned long) key,
@@ -728,6 +749,7 @@ struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry,
 			nlink = ovl_get_nlink(lowerdentry, upperdentry, nlink);
 		set_nlink(inode, nlink);
 	} else {
+		/* Lower hardlink that will be broken on copy up */
 		inode = new_inode(sb);
 		if (!inode)
 			goto out_nomem;