1 files changed, 49 insertions, 14 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 6f0683c68952..dc4c47ab9588 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -29,6 +29,7 @@
 #include "cifsproto.h"
 #include "cifs_debug.h"
 #include "cifs_fs_sb.h"
+#include "fscache.h"
 
 
 static void cifs_set_ops(struct inode *inode, const bool is_dfs_referral)
@@ -288,7 +289,7 @@ int cifs_get_file_info_unix(struct file *filp)
         struct inode *inode = filp->f_path.dentry->d_inode;
         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
         struct cifsTconInfo *tcon = cifs_sb->tcon;
-        struct cifsFileInfo *cfile = (struct cifsFileInfo *) filp->private_data;
+        struct cifsFileInfo *cfile = filp->private_data;
 
         xid = GetXid();
         rc = CIFSSMBUnixQFileInfo(xid, tcon, cfile->netfid, &find_data);
@@ -515,7 +516,7 @@ int cifs_get_file_info(struct file *filp)
         struct inode *inode = filp->f_path.dentry->d_inode;
         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
         struct cifsTconInfo *tcon = cifs_sb->tcon;
-        struct cifsFileInfo *cfile = (struct cifsFileInfo *) filp->private_data;
+        struct cifsFileInfo *cfile = filp->private_data;
 
         xid = GetXid();
         rc = CIFSSMBQFileInfo(xid, tcon, cfile->netfid, &find_data);
@@ -723,18 +724,17 @@ cifs_find_inode(struct inode *inode, void *opaque)
 {
         struct cifs_fattr *fattr = (struct cifs_fattr *) opaque;
 
+        /* don't match inode with different uniqueid */
         if (CIFS_I(inode)->uniqueid != fattr->cf_uniqueid)
                 return 0;
 
-        /*
-         * uh oh -- it's a directory. We can't use it since hardlinked dirs are
-         * verboten. Disable serverino and return it as if it were found, the
-         * caller can discard it, generate a uniqueid and retry the find
-         */
-        if (S_ISDIR(inode->i_mode) && !list_empty(&inode->i_dentry)) {
+        /* don't match inode of different type */
+        if ((inode->i_mode & S_IFMT) != (fattr->cf_mode & S_IFMT))
+                return 0;
+
+        /* if it's not a directory or has no dentries, then flag it */
+        if (S_ISDIR(inode->i_mode) && !list_empty(&inode->i_dentry))
                 fattr->cf_flags |= CIFS_FATTR_INO_COLLISION;
-                cifs_autodisable_serverino(CIFS_SB(inode->i_sb));
-        }
 
         return 1;
 }
@@ -748,6 +748,27 @@ cifs_init_inode(struct inode *inode, void *opaque)
         return 0;
 }
 
+/*
+ * walk dentry list for an inode and report whether it has aliases that
+ * are hashed. We use this to determine if a directory inode can actually
+ * be used.
+ */
+static bool
+inode_has_hashed_dentries(struct inode *inode)
+{
+        struct dentry *dentry;
+
+        spin_lock(&dcache_lock);
+        list_for_each_entry(dentry, &inode->i_dentry, d_alias) {
+                if (!d_unhashed(dentry) || IS_ROOT(dentry)) {
+                        spin_unlock(&dcache_lock);
+                        return true;
+                }
+        }
+        spin_unlock(&dcache_lock);
+        return false;
+}
+
 /* Given fattrs, get a corresponding inode */
 struct inode *
 cifs_iget(struct super_block *sb, struct cifs_fattr *fattr)
@@ -763,12 +784,16 @@ retry_iget5_locked:
 
         inode = iget5_locked(sb, hash, cifs_find_inode, cifs_init_inode, fattr);
         if (inode) {
-                /* was there a problematic inode number collision? */
+                /* was there a potentially problematic inode collision? */
                 if (fattr->cf_flags & CIFS_FATTR_INO_COLLISION) {
-                        iput(inode);
-                        fattr->cf_uniqueid = iunique(sb, ROOT_I);
                         fattr->cf_flags &= ~CIFS_FATTR_INO_COLLISION;
-                        goto retry_iget5_locked;
+
+                        if (inode_has_hashed_dentries(inode)) {
+                                cifs_autodisable_serverino(CIFS_SB(sb));
+                                iput(inode);
+                                fattr->cf_uniqueid = iunique(sb, ROOT_I);
+                                goto retry_iget5_locked;
+                        }
                 }
 
                 cifs_fattr_to_inode(inode, fattr);
@@ -776,6 +801,10 @@ retry_iget5_locked:
                         inode->i_flags |= S_NOATIME | S_NOCMTIME;
                 if (inode->i_state & I_NEW) {
                         inode->i_ino = hash;
+#ifdef CONFIG_CIFS_FSCACHE
+                        /* initialize per-inode cache cookie pointer */
+                        CIFS_I(inode)->fscache = NULL;
+#endif
                         unlock_new_inode(inode);
                 }
         }
@@ -807,6 +836,11 @@ struct inode *cifs_root_iget(struct super_block *sb, unsigned long ino)
         if (!inode)
                 return ERR_PTR(-ENOMEM);
 
+#ifdef CONFIG_CIFS_FSCACHE
+        /* populate tcon->resource_id */
+        cifs_sb->tcon->resource_id = CIFS_I(inode)->uniqueid;
+#endif
+
         if (rc && cifs_sb->tcon->ipc) {
                 cFYI(1, "ipc connection - fake read inode");
                 inode->i_mode |= S_IFDIR;
@@ -1568,6 +1602,7 @@ cifs_invalidate_mapping(struct inode *inode)
                         cifs_i->write_behind_rc = rc;
         }
         invalidate_remote_inode(inode);
+        cifs_fscache_reset_inode_cookie(inode);
 }
 
 int cifs_revalidate_file(struct file *filp)