[PATCH] v9fs: VFS superblock operations and glue

This part of the patch contains VFS superblock and mapping code.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 271 insertions, 0 deletions

diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
new file mode 100644
index 000000000000..ce0778acc90a
--- /dev/null
+++ b/fs/9p/vfs_super.c
@@ -0,0 +1,271 @@
+/*
+ *  linux/fs/9p/vfs_super.c
+ *
+ * This file contians superblock ops for 9P2000. It is intended that
+ * you mount this file system on directories.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/smp_lock.h>
+#include <linux/inet.h>
+#include <linux/pagemap.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/idr.h>
+
+#include "debug.h"
+#include "v9fs.h"
+#include "9p.h"
+#include "v9fs_vfs.h"
+#include "conv.h"
+#include "fid.h"
+
+static void v9fs_clear_inode(struct inode *);
+static struct super_operations v9fs_super_ops;
+
+/**
+ * v9fs_clear_inode - release an inode
+ * @inode: inode to release
+ *
+ */
+
+static void v9fs_clear_inode(struct inode *inode)
+{
+        filemap_fdatawrite(inode->i_mapping);
+}
+
+/**
+ * v9fs_set_super - set the superblock
+ * @s: super block
+ * @data: file system specific data
+ *
+ */
+
+static int v9fs_set_super(struct super_block *s, void *data)
+{
+        s->s_fs_info = data;
+        return set_anon_super(s, data);
+}
+
+/**
+ * v9fs_fill_super - populate superblock with info
+ * @sb: superblock
+ * @v9ses: session information
+ *
+ */
+
+static void
+v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
+                int flags)
+{
+        sb->s_maxbytes = MAX_LFS_FILESIZE;
+        sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
+        sb->s_blocksize = 1 << sb->s_blocksize_bits;
+        sb->s_magic = V9FS_MAGIC;
+        sb->s_op = &v9fs_super_ops;
+
+        sb->s_flags = flags | MS_ACTIVE | MS_SYNCHRONOUS | MS_DIRSYNC |
+            MS_NODIRATIME | MS_NOATIME;
+}
+
+/**
+ * v9fs_get_sb - mount a superblock
+ * @fs_type: file system type
+ * @flags: mount flags
+ * @dev_name: device name that was mounted
+ * @data: mount options
+ *
+ */
+
+static struct super_block *v9fs_get_sb(struct file_system_type
+                                       *fs_type, int flags,
+                                       const char *dev_name, void *data)
+{
+        struct super_block *sb = NULL;
+        struct v9fs_fcall *fcall = NULL;
+        struct inode *inode = NULL;
+        struct dentry *root = NULL;
+        struct v9fs_session_info *v9ses = NULL;
+        struct v9fs_fid *root_fid = NULL;
+        int mode = S_IRWXUGO | S_ISVTX;
+        uid_t uid = current->fsuid;
+        gid_t gid = current->fsgid;
+        int stat_result = 0;
+        int newfid = 0;
+        int retval = 0;
+
+        dprintk(DEBUG_VFS, " \n");
+
+        v9ses = kcalloc(1, sizeof(struct v9fs_session_info), GFP_KERNEL);
+        if (!v9ses)
+                return ERR_PTR(-ENOMEM);
+
+        if ((newfid = v9fs_session_init(v9ses, dev_name, data)) < 0) {
+                dprintk(DEBUG_ERROR, "problem initiating session\n");
+                retval = newfid;
+                goto free_session;
+        }
+
+        sb = sget(fs_type, NULL, v9fs_set_super, v9ses);
+
+        v9fs_fill_super(sb, v9ses, flags);
+
+        inode = v9fs_get_inode(sb, S_IFDIR | mode);
+        if (IS_ERR(inode)) {
+                retval = PTR_ERR(inode);
+                goto put_back_sb;
+        }
+
+        inode->i_uid = uid;
+        inode->i_gid = gid;
+
+        root = d_alloc_root(inode);
+
+        if (!root) {
+                retval = -ENOMEM;
+                goto release_inode;
+        }
+
+        sb->s_root = root;
+
+        /* Setup the Root Inode */
+        root_fid = v9fs_fid_create(root);
+        if (root_fid == NULL) {
+                retval = -ENOMEM;
+                goto release_dentry;
+        }
+
+        root_fid->fidopen = 0;
+        root_fid->v9ses = v9ses;
+
+        stat_result = v9fs_t_stat(v9ses, newfid, &fcall);
+        if (stat_result < 0) {
+                dprintk(DEBUG_ERROR, "stat error\n");
+                v9fs_t_clunk(v9ses, newfid, NULL);
+                v9fs_put_idpool(newfid, &v9ses->fidpool);
+        } else {
+                root_fid->fid = newfid;
+                root_fid->qid = fcall->params.rstat.stat->qid;
+                root->d_inode->i_ino =
+                    v9fs_qid2ino(&fcall->params.rstat.stat->qid);
+                v9fs_mistat2inode(fcall->params.rstat.stat, root->d_inode, sb);
+        }
+
+        kfree(fcall);
+
+        if (stat_result < 0) {
+                retval = stat_result;
+                goto release_dentry;
+        }
+
+        return sb;
+
+      release_dentry:
+        dput(sb->s_root);
+
+      release_inode:
+        iput(inode);
+
+      put_back_sb:
+        up_write(&sb->s_umount);
+        deactivate_super(sb);
+        v9fs_session_close(v9ses);
+
+      free_session:
+        kfree(v9ses);
+
+        return ERR_PTR(retval);
+}
+
+/**
+ * v9fs_kill_super - Kill Superblock
+ * @s: superblock
+ *
+ */
+
+static void v9fs_kill_super(struct super_block *s)
+{
+        struct v9fs_session_info *v9ses = s->s_fs_info;
+
+        dprintk(DEBUG_VFS, " %p\n", s);
+
+        v9fs_dentry_release(s->s_root); /* clunk root */
+
+        kill_anon_super(s);
+
+        v9fs_session_close(v9ses);
+        kfree(v9ses);
+        dprintk(DEBUG_VFS, "exiting kill_super\n");
+}
+
+/**
+ * v9fs_show_options - Show mount options in /proc/mounts
+ * @m: seq_file to write to
+ * @mnt: mount descriptor
+ *
+ */
+
+static int v9fs_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+        struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info;
+
+        if (v9ses->debug != 0)
+                seq_printf(m, ",debug=%u", v9ses->debug);
+        if (v9ses->port != V9FS_PORT)
+                seq_printf(m, ",port=%u", v9ses->port);
+        if (v9ses->maxdata != 9000)
+                seq_printf(m, ",msize=%u", v9ses->maxdata);
+        if (v9ses->afid != ~0)
+                seq_printf(m, ",afid=%u", v9ses->afid);
+        if (v9ses->proto == PROTO_UNIX)
+                seq_puts(m, ",proto=unix");
+        if (v9ses->extended == 0)
+                seq_puts(m, ",noextend");
+        if (v9ses->nodev == 1)
+                seq_puts(m, ",nodevmap");
+        seq_printf(m, ",name=%s", v9ses->name);
+        seq_printf(m, ",aname=%s", v9ses->remotename);
+        seq_printf(m, ",uid=%u", v9ses->uid);
+        seq_printf(m, ",gid=%u", v9ses->gid);
+        return 0;
+}
+
+static struct super_operations v9fs_super_ops = {
+        .statfs = simple_statfs,
+        .clear_inode = v9fs_clear_inode,
+        .show_options = v9fs_show_options,
+};
+
+struct file_system_type v9fs_fs_type = {
+        .name = "9P",
+        .get_sb = v9fs_get_sb,
+        .kill_sb = v9fs_kill_super,
+        .owner = THIS_MODULE,
+};