CIFS: Simplify mount code for further shared sb capability

Reorganize code to get mount option at first and when get a superblock.
This lets us use shared superblock model further for equal mounts.

Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 57 insertions, 31 deletions

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 493b74ca5648..131afadce0e0 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -104,19 +104,16 @@ cifs_sb_deactive(struct super_block *sb)
 }
 
 static int
-cifs_read_super(struct super_block *sb, void *data,
-                const char *devname, int silent)
+cifs_read_super(struct super_block *sb, struct cifs_sb_info *cifs_sb,
+                void *data, struct smb_vol *volume_info, const char *devname,
+                int silent)
 {
         struct inode *inode;
-        struct cifs_sb_info *cifs_sb;
         int rc = 0;
 
         /* BB should we make this contingent on mount parm? */
         sb->s_flags |= MS_NODIRATIME | MS_NOATIME;
-        sb->s_fs_info = kzalloc(sizeof(struct cifs_sb_info), GFP_KERNEL);
-        cifs_sb = CIFS_SB(sb);
-        if (cifs_sb == NULL)
-                return -ENOMEM;
+        sb->s_fs_info = cifs_sb;
 
         spin_lock_init(&cifs_sb->tlink_tree_lock);
         cifs_sb->tlink_tree = RB_ROOT;
@@ -128,22 +125,10 @@ cifs_read_super(struct super_block *sb, void *data,
         }
         cifs_sb->bdi.ra_pages = default_backing_dev_info.ra_pages;
 
-        /*
-         * Copy mount params to sb for use in submounts. Better to do
-         * the copy here and deal with the error before cleanup gets
-         * complicated post-mount.
-         */
-        if (data) {
-                cifs_sb->mountdata = kstrndup(data, PAGE_SIZE, GFP_KERNEL);
-                if (cifs_sb->mountdata == NULL) {
-                        bdi_destroy(&cifs_sb->bdi);
-                        kfree(sb->s_fs_info);
-                        sb->s_fs_info = NULL;
-                        return -ENOMEM;
-                }
-        }
+        if (data)
+                cifs_sb->mountdata = data;
 
-        rc = cifs_mount(sb, cifs_sb, devname);
+        rc = cifs_mount(sb, cifs_sb, volume_info, devname);
 
         if (rc) {
                 if (!silent)
@@ -561,27 +546,68 @@ static const struct super_operations cifs_super_ops = {
 
 static struct dentry *
 cifs_do_mount(struct file_system_type *fs_type,
-            int flags, const char *dev_name, void *data)
+              int flags, const char *dev_name, void *data)
 {
         int rc;
         struct super_block *sb;
-
-        sb = sget(fs_type, NULL, set_anon_super, NULL);
+        struct cifs_sb_info *cifs_sb;
+        struct smb_vol *volume_info;
+        struct dentry *root;
+        char *copied_data = NULL;
 
         cFYI(1, "Devname: %s flags: %d ", dev_name, flags);
 
-        if (IS_ERR(sb))
-                return ERR_CAST(sb);
+        rc = cifs_setup_volume_info(&volume_info, (char *)data, dev_name);
+        if (rc)
+                return ERR_PTR(rc);
+
+        cifs_sb = kzalloc(sizeof(struct cifs_sb_info), GFP_KERNEL);
+        if (cifs_sb == NULL) {
+                root = ERR_PTR(-ENOMEM);
+                goto out;
+        }
+
+        cifs_setup_cifs_sb(volume_info, cifs_sb);
+
+        sb = sget(fs_type, NULL, set_anon_super, NULL);
+        if (IS_ERR(sb)) {
+                kfree(cifs_sb);
+                root = ERR_CAST(sb);
+                goto out;
+        }
 
         sb->s_flags = flags;
 
-        rc = cifs_read_super(sb, data, dev_name, flags & MS_SILENT ? 1 : 0);
+        /*
+         * Copy mount params for use in submounts. Better to do
+         * the copy here and deal with the error before cleanup gets
+         * complicated post-mount.
+         */
+        copied_data = kstrndup(data, PAGE_SIZE, GFP_KERNEL);
+        if (copied_data == NULL) {
+                root = ERR_PTR(-ENOMEM);
+                goto err_out;
+        }
+
+        rc = cifs_read_super(sb, cifs_sb, copied_data, volume_info, dev_name,
+                             flags & MS_SILENT ? 1 : 0);
         if (rc) {
-                deactivate_locked_super(sb);
-                return ERR_PTR(rc);
+                root = ERR_PTR(rc);
+                goto err_out;
         }
+
         sb->s_flags |= MS_ACTIVE;
-        return dget(sb->s_root);
+
+        root = dget(sb->s_root);
+out:
+        cifs_cleanup_volume_info(&volume_info);
+        return root;
+
+err_out:
+        kfree(cifs_sb);
+        deactivate_locked_super(sb);
+        cifs_cleanup_volume_info(&volume_info);
+        return root;
 }
 
 static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,