Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 664 insertions, 0 deletions

diff --git a/fs/omfs/inode.c b/fs/omfs/inode.c
new file mode 100644
index 000000000..1d915ef72
--- /dev/null
+++ b/fs/omfs/inode.c
@@ -0,0 +1,664 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Optimized MPEG FS - inode and super operations.
+ * Copyright (C) 2006 Bob Copeland <me@bobcopeland.com>
+ */
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/vfs.h>
+#include <linux/cred.h>
+#include <linux/buffer_head.h>
+#include <linux/vmalloc.h>
+#include <linux/writeback.h>
+#include <linux/seq_file.h>
+#include <linux/crc-itu-t.h>
+#include <linux/fs_struct.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
+#include "omfs.h"
+
+MODULE_AUTHOR("Bob Copeland <me@bobcopeland.com>");
+MODULE_DESCRIPTION("OMFS (ReplayTV/Karma) Filesystem for Linux");
+MODULE_LICENSE("GPL");
+
+struct buffer_head *omfs_bread(struct super_block *sb, sector_t block)
+{
+	struct omfs_sb_info *sbi = OMFS_SB(sb);
+	if (block >= sbi->s_num_blocks)
+		return NULL;
+
+	return sb_bread(sb, clus_to_blk(sbi, block));
+}
+
+struct inode *omfs_new_inode(struct inode *dir, umode_t mode)
+{
+	struct inode *inode;
+	u64 new_block;
+	int err;
+	int len;
+	struct omfs_sb_info *sbi = OMFS_SB(dir->i_sb);
+
+	inode = new_inode(dir->i_sb);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+
+	err = omfs_allocate_range(dir->i_sb, sbi->s_mirrors, sbi->s_mirrors,
+			&new_block, &len);
+	if (err)
+		goto fail;
+
+	inode->i_ino = new_block;
+	inode_init_owner(&nop_mnt_idmap, inode, NULL, mode);
+	inode->i_mapping->a_ops = &omfs_aops;
+
+	simple_inode_init_ts(inode);
+	switch (mode & S_IFMT) {
+	case S_IFDIR:
+		inode->i_op = &omfs_dir_inops;
+		inode->i_fop = &omfs_dir_operations;
+		inode->i_size = sbi->s_sys_blocksize;
+		inc_nlink(inode);
+		break;
+	case S_IFREG:
+		inode->i_op = &omfs_file_inops;
+		inode->i_fop = &omfs_file_operations;
+		inode->i_size = 0;
+		break;
+	}
+
+	insert_inode_hash(inode);
+	mark_inode_dirty(inode);
+	return inode;
+fail:
+	make_bad_inode(inode);
+	iput(inode);
+	return ERR_PTR(err);
+}
+
+/*
+ * Update the header checksums for a dirty inode based on its contents.
+ * Caller is expected to hold the buffer head underlying oi and mark it
+ * dirty.
+ */
+static void omfs_update_checksums(struct omfs_inode *oi)
+{
+	int xor, i, ofs = 0, count;
+	u16 crc = 0;
+	unsigned char *ptr = (unsigned char *) oi;
+
+	count = be32_to_cpu(oi->i_head.h_body_size);
+	ofs = sizeof(struct omfs_header);
+
+	crc = crc_itu_t(crc, ptr + ofs, count);
+	oi->i_head.h_crc = cpu_to_be16(crc);
+
+	xor = ptr[0];
+	for (i = 1; i < OMFS_XOR_COUNT; i++)
+		xor ^= ptr[i];
+
+	oi->i_head.h_check_xor = xor;
+}
+
+static int __omfs_write_inode(struct inode *inode, int wait)
+{
+	struct omfs_inode *oi;
+	struct omfs_sb_info *sbi = OMFS_SB(inode->i_sb);
+	struct buffer_head *bh, *bh2;
+	u64 ctime;
+	int i;
+	int ret = -EIO;
+	int sync_failed = 0;
+
+	/* get current inode since we may have written sibling ptrs etc. */
+	bh = omfs_bread(inode->i_sb, inode->i_ino);
+	if (!bh)
+		goto out;
+
+	oi = (struct omfs_inode *) bh->b_data;
+
+	oi->i_head.h_self = cpu_to_be64(inode->i_ino);
+	if (S_ISDIR(inode->i_mode))
+		oi->i_type = OMFS_DIR;
+	else if (S_ISREG(inode->i_mode))
+		oi->i_type = OMFS_FILE;
+	else {
+		printk(KERN_WARNING "omfs: unknown file type: %d\n",
+			inode->i_mode);
+		goto out_brelse;
+	}
+
+	oi->i_head.h_body_size = cpu_to_be32(sbi->s_sys_blocksize -
+		sizeof(struct omfs_header));
+	oi->i_head.h_version = 1;
+	oi->i_head.h_type = OMFS_INODE_NORMAL;
+	oi->i_head.h_magic = OMFS_IMAGIC;
+	oi->i_size = cpu_to_be64(inode->i_size);
+
+	ctime = inode_get_ctime_sec(inode) * 1000LL +
+		((inode_get_ctime_nsec(inode) + 999)/1000);
+	oi->i_ctime = cpu_to_be64(ctime);
+
+	omfs_update_checksums(oi);
+
+	mark_buffer_dirty(bh);
+	if (wait) {
+		sync_dirty_buffer(bh);
+		if (buffer_req(bh) && !buffer_uptodate(bh))
+			sync_failed = 1;
+	}
+
+	/* if mirroring writes, copy to next fsblock */
+	for (i = 1; i < sbi->s_mirrors; i++) {
+		bh2 = omfs_bread(inode->i_sb, inode->i_ino + i);
+		if (!bh2)
+			goto out_brelse;
+
+		memcpy(bh2->b_data, bh->b_data, bh->b_size);
+		mark_buffer_dirty(bh2);
+		if (wait) {
+			sync_dirty_buffer(bh2);
+			if (buffer_req(bh2) && !buffer_uptodate(bh2))
+				sync_failed = 1;
+		}
+		brelse(bh2);
+	}
+	ret = (sync_failed) ? -EIO : 0;
+out_brelse:
+	brelse(bh);
+out:
+	return ret;
+}
+
+static int omfs_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+	return __omfs_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
+}
+
+int omfs_sync_inode(struct inode *inode)
+{
+	return __omfs_write_inode(inode, 1);
+}
+
+/*
+ * called when an entry is deleted, need to clear the bits in the
+ * bitmaps.
+ */
+static void omfs_evict_inode(struct inode *inode)
+{
+	truncate_inode_pages_final(&inode->i_data);
+	clear_inode(inode);
+
+	if (inode->i_nlink)
+		return;
+
+	if (S_ISREG(inode->i_mode)) {
+		inode->i_size = 0;
+		omfs_shrink_inode(inode);
+	}
+
+	omfs_clear_range(inode->i_sb, inode->i_ino, 2);
+}
+
+struct inode *omfs_iget(struct super_block *sb, ino_t ino)
+{
+	struct omfs_sb_info *sbi = OMFS_SB(sb);
+	struct omfs_inode *oi;
+	struct buffer_head *bh;
+	u64 ctime;
+	unsigned long nsecs;
+	struct inode *inode;
+
+	inode = iget_locked(sb, ino);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode_state_read_once(inode) & I_NEW))
+		return inode;
+
+	bh = omfs_bread(inode->i_sb, ino);
+	if (!bh)
+		goto iget_failed;
+
+	oi = (struct omfs_inode *)bh->b_data;
+
+	/* check self */
+	if (ino != be64_to_cpu(oi->i_head.h_self))
+		goto fail_bh;
+
+	inode->i_uid = sbi->s_uid;
+	inode->i_gid = sbi->s_gid;
+
+	ctime = be64_to_cpu(oi->i_ctime);
+	nsecs = do_div(ctime, 1000) * 1000L;
+
+	inode_set_atime(inode, ctime, nsecs);
+	inode_set_mtime(inode, ctime, nsecs);
+	inode_set_ctime(inode, ctime, nsecs);
+
+	inode->i_mapping->a_ops = &omfs_aops;
+
+	switch (oi->i_type) {
+	case OMFS_DIR:
+		inode->i_mode = S_IFDIR | (S_IRWXUGO & ~sbi->s_dmask);
+		inode->i_op = &omfs_dir_inops;
+		inode->i_fop = &omfs_dir_operations;
+		inode->i_size = sbi->s_sys_blocksize;
+		inc_nlink(inode);
+		break;
+	case OMFS_FILE:
+		inode->i_mode = S_IFREG | (S_IRWXUGO & ~sbi->s_fmask);
+		inode->i_fop = &omfs_file_operations;
+		inode->i_size = be64_to_cpu(oi->i_size);
+		break;
+	}
+	brelse(bh);
+	unlock_new_inode(inode);
+	return inode;
+fail_bh:
+	brelse(bh);
+iget_failed:
+	iget_failed(inode);
+	return ERR_PTR(-EIO);
+}
+
+static void omfs_put_super(struct super_block *sb)
+{
+	struct omfs_sb_info *sbi = OMFS_SB(sb);
+	kfree(sbi->s_imap);
+	kfree(sbi);
+	sb->s_fs_info = NULL;
+}
+
+static int omfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct super_block *s = dentry->d_sb;
+	struct omfs_sb_info *sbi = OMFS_SB(s);
+	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
+
+	buf->f_type = OMFS_MAGIC;
+	buf->f_bsize = sbi->s_blocksize;
+	buf->f_blocks = sbi->s_num_blocks;
+	buf->f_files = sbi->s_num_blocks;
+	buf->f_namelen = OMFS_NAMELEN;
+	buf->f_fsid = u64_to_fsid(id);
+
+	buf->f_bfree = buf->f_bavail = buf->f_ffree =
+		omfs_count_free(s);
+
+	return 0;
+}
+
+/*
+ * Display the mount options in /proc/mounts.
+ */
+static int omfs_show_options(struct seq_file *m, struct dentry *root)
+{
+	struct omfs_sb_info *sbi = OMFS_SB(root->d_sb);
+	umode_t cur_umask = current_umask();
+
+	if (!uid_eq(sbi->s_uid, current_uid()))
+		seq_printf(m, ",uid=%u",
+			   from_kuid_munged(&init_user_ns, sbi->s_uid));
+	if (!gid_eq(sbi->s_gid, current_gid()))
+		seq_printf(m, ",gid=%u",
+			   from_kgid_munged(&init_user_ns, sbi->s_gid));
+
+	if (sbi->s_dmask == sbi->s_fmask) {
+		if (sbi->s_fmask != cur_umask)
+			seq_printf(m, ",umask=%o", sbi->s_fmask);
+	} else {
+		if (sbi->s_dmask != cur_umask)
+			seq_printf(m, ",dmask=%o", sbi->s_dmask);
+		if (sbi->s_fmask != cur_umask)
+			seq_printf(m, ",fmask=%o", sbi->s_fmask);
+	}
+
+	return 0;
+}
+
+static const struct super_operations omfs_sops = {
+	.write_inode	= omfs_write_inode,
+	.evict_inode	= omfs_evict_inode,
+	.put_super	= omfs_put_super,
+	.statfs		= omfs_statfs,
+	.show_options	= omfs_show_options,
+};
+
+/*
+ * For Rio Karma, there is an on-disk free bitmap whose location is
+ * stored in the root block.  For ReplayTV, there is no such free bitmap
+ * so we have to walk the tree.  Both inodes and file data are allocated
+ * from the same map.  This array can be big (300k) so we allocate
+ * in units of the blocksize.
+ */
+static int omfs_get_imap(struct super_block *sb)
+{
+	unsigned int bitmap_size, array_size;
+	int count;
+	struct omfs_sb_info *sbi = OMFS_SB(sb);
+	struct buffer_head *bh;
+	unsigned long **ptr;
+	sector_t block;
+
+	bitmap_size = DIV_ROUND_UP(sbi->s_num_blocks, 8);
+	array_size = DIV_ROUND_UP(bitmap_size, sb->s_blocksize);
+
+	if (sbi->s_bitmap_ino == ~0ULL)
+		goto out;
+
+	sbi->s_imap_size = array_size;
+	sbi->s_imap = kcalloc(array_size, sizeof(unsigned long *), GFP_KERNEL);
+	if (!sbi->s_imap)
+		goto nomem;
+
+	block = clus_to_blk(sbi, sbi->s_bitmap_ino);
+	if (block >= sbi->s_num_blocks)
+		goto nomem;
+
+	ptr = sbi->s_imap;
+	for (count = bitmap_size; count > 0; count -= sb->s_blocksize) {
+		bh = sb_bread(sb, block++);
+		if (!bh)
+			goto nomem_free;
+		*ptr = kmemdup(bh->b_data, sb->s_blocksize, GFP_KERNEL);
+		if (!*ptr) {
+			brelse(bh);
+			goto nomem_free;
+		}
+		if (count < sb->s_blocksize)
+			memset((void *)*ptr + count, 0xff,
+				sb->s_blocksize - count);
+		brelse(bh);
+		ptr++;
+	}
+out:
+	return 0;
+
+nomem_free:
+	for (count = 0; count < array_size; count++)
+		kfree(sbi->s_imap[count]);
+
+	kfree(sbi->s_imap);
+nomem:
+	sbi->s_imap = NULL;
+	sbi->s_imap_size = 0;
+	return -ENOMEM;
+}
+
+struct omfs_mount_options {
+	kuid_t s_uid;
+	kgid_t s_gid;
+	int s_dmask;
+	int s_fmask;
+};
+
+enum {
+	Opt_uid, Opt_gid, Opt_umask, Opt_dmask, Opt_fmask,
+};
+
+static const struct fs_parameter_spec omfs_param_spec[] = {
+	fsparam_uid	("uid",		Opt_uid),
+	fsparam_gid	("gid",		Opt_gid),
+	fsparam_u32oct	("umask",	Opt_umask),
+	fsparam_u32oct	("dmask",	Opt_dmask),
+	fsparam_u32oct	("fmask",	Opt_fmask),
+	{}
+};
+
+static int
+omfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+	struct omfs_mount_options *opts = fc->fs_private;
+	int token;
+	struct fs_parse_result result;
+
+	/* All options are ignored on remount */
+	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE)
+		return 0;
+
+	token = fs_parse(fc, omfs_param_spec, param, &result);
+	if (token < 0)
+		return token;
+
+	switch (token) {
+	case Opt_uid:
+		opts->s_uid = result.uid;
+		break;
+	case Opt_gid:
+		opts->s_gid = result.gid;
+		break;
+	case Opt_umask:
+		opts->s_fmask = opts->s_dmask = result.uint_32;
+		break;
+	case Opt_dmask:
+		opts->s_dmask = result.uint_32;
+		break;
+	case Opt_fmask:
+		opts->s_fmask = result.uint_32;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void
+omfs_set_options(struct omfs_sb_info *sbi, struct omfs_mount_options *opts)
+{
+	sbi->s_uid = opts->s_uid;
+	sbi->s_gid = opts->s_gid;
+	sbi->s_dmask = opts->s_dmask;
+	sbi->s_fmask = opts->s_fmask;
+}
+
+static int omfs_fill_super(struct super_block *sb, struct fs_context *fc)
+{
+	struct buffer_head *bh, *bh2;
+	struct omfs_super_block *omfs_sb;
+	struct omfs_root_block *omfs_rb;
+	struct omfs_sb_info *sbi;
+	struct inode *root;
+	struct omfs_mount_options *parsed_opts = fc->fs_private;
+	int ret = -EINVAL;
+	int silent = fc->sb_flags & SB_SILENT;
+
+	sbi = kzalloc_obj(struct omfs_sb_info);
+	if (!sbi)
+		return -ENOMEM;
+
+	sb->s_fs_info = sbi;
+
+	omfs_set_options(sbi, parsed_opts);
+
+	sb->s_maxbytes = 0xffffffff;
+
+	sb->s_time_gran = NSEC_PER_MSEC;
+	sb->s_time_min = 0;
+	sb->s_time_max = U64_MAX / MSEC_PER_SEC;
+
+	if (!sb_set_blocksize(sb, 0x200))
+		goto end;
+
+	bh = sb_bread(sb, 0);
+	if (!bh)
+		goto end;
+
+	omfs_sb = (struct omfs_super_block *)bh->b_data;
+
+	if (omfs_sb->s_magic != cpu_to_be32(OMFS_MAGIC)) {
+		if (!silent)
+			printk(KERN_ERR "omfs: Invalid superblock (%x)\n",
+				   omfs_sb->s_magic);
+		goto out_brelse_bh;
+	}
+	sb->s_magic = OMFS_MAGIC;
+
+	sbi->s_num_blocks = be64_to_cpu(omfs_sb->s_num_blocks);
+	sbi->s_blocksize = be32_to_cpu(omfs_sb->s_blocksize);
+	sbi->s_mirrors = be32_to_cpu(omfs_sb->s_mirrors);
+	sbi->s_root_ino = be64_to_cpu(omfs_sb->s_root_block);
+	sbi->s_sys_blocksize = be32_to_cpu(omfs_sb->s_sys_blocksize);
+	mutex_init(&sbi->s_bitmap_lock);
+
+	if (sbi->s_num_blocks > OMFS_MAX_BLOCKS) {
+		printk(KERN_ERR "omfs: sysblock number (%llx) is out of range\n",
+		       (unsigned long long)sbi->s_num_blocks);
+		goto out_brelse_bh;
+	}
+
+	if (sbi->s_sys_blocksize > PAGE_SIZE) {
+		printk(KERN_ERR "omfs: sysblock size (%d) is out of range\n",
+			sbi->s_sys_blocksize);
+		goto out_brelse_bh;
+	}
+
+	if (sbi->s_sys_blocksize < OMFS_DIR_START) {
+		printk(KERN_ERR "omfs: sysblock size (%d) is too small\n",
+			sbi->s_sys_blocksize);
+		goto out_brelse_bh;
+	}
+
+	if (sbi->s_blocksize < sbi->s_sys_blocksize ||
+	    sbi->s_blocksize > OMFS_MAX_BLOCK_SIZE) {
+		printk(KERN_ERR "omfs: block size (%d) is out of range\n",
+			sbi->s_blocksize);
+		goto out_brelse_bh;
+	}
+
+	/*
+	 * Use sys_blocksize as the fs block since it is smaller than a
+	 * page while the fs blocksize can be larger.
+	 */
+	if (!sb_set_blocksize(sb, sbi->s_sys_blocksize))
+		goto out_brelse_bh;
+
+	/*
+	 * ...and the difference goes into a shift.  sys_blocksize is always
+	 * a power of two factor of blocksize.
+	 */
+	sbi->s_block_shift = get_bitmask_order(sbi->s_blocksize) -
+		get_bitmask_order(sbi->s_sys_blocksize);
+
+	bh2 = omfs_bread(sb, be64_to_cpu(omfs_sb->s_root_block));
+	if (!bh2)
+		goto out_brelse_bh;
+
+	omfs_rb = (struct omfs_root_block *)bh2->b_data;
+
+	sbi->s_bitmap_ino = be64_to_cpu(omfs_rb->r_bitmap);
+	sbi->s_clustersize = be32_to_cpu(omfs_rb->r_clustersize);
+
+	if (sbi->s_num_blocks != be64_to_cpu(omfs_rb->r_num_blocks)) {
+		printk(KERN_ERR "omfs: block count discrepancy between "
+			"super and root blocks (%llx, %llx)\n",
+			(unsigned long long)sbi->s_num_blocks,
+			(unsigned long long)be64_to_cpu(omfs_rb->r_num_blocks));
+		goto out_brelse_bh2;
+	}
+
+	if (sbi->s_bitmap_ino != ~0ULL &&
+	    sbi->s_bitmap_ino > sbi->s_num_blocks) {
+		printk(KERN_ERR "omfs: free space bitmap location is corrupt "
+			"(%llx, total blocks %llx)\n",
+			(unsigned long long) sbi->s_bitmap_ino,
+			(unsigned long long) sbi->s_num_blocks);
+		goto out_brelse_bh2;
+	}
+	if (sbi->s_clustersize < 1 ||
+	    sbi->s_clustersize > OMFS_MAX_CLUSTER_SIZE) {
+		printk(KERN_ERR "omfs: cluster size out of range (%d)",
+			sbi->s_clustersize);
+		goto out_brelse_bh2;
+	}
+
+	ret = omfs_get_imap(sb);
+	if (ret)
+		goto out_brelse_bh2;
+
+	sb->s_op = &omfs_sops;
+
+	root = omfs_iget(sb, be64_to_cpu(omfs_rb->r_root_dir));
+	if (IS_ERR(root)) {
+		ret = PTR_ERR(root);
+		goto out_brelse_bh2;
+	}
+
+	sb->s_root = d_make_root(root);
+	if (!sb->s_root) {
+		ret = -ENOMEM;
+		goto out_brelse_bh2;
+	}
+	printk(KERN_DEBUG "omfs: Mounted volume %s\n", omfs_rb->r_name);
+
+	ret = 0;
+out_brelse_bh2:
+	brelse(bh2);
+out_brelse_bh:
+	brelse(bh);
+end:
+	if (ret)
+		kfree(sbi);
+	return ret;
+}
+
+static int omfs_get_tree(struct fs_context *fc)
+{
+	return get_tree_bdev(fc, omfs_fill_super);
+}
+
+static void omfs_free_fc(struct fs_context *fc);
+
+static const struct fs_context_operations omfs_context_ops = {
+	.parse_param	= omfs_parse_param,
+	.get_tree	= omfs_get_tree,
+	.free		= omfs_free_fc,
+};
+
+static int omfs_init_fs_context(struct fs_context *fc)
+{
+	struct omfs_mount_options *opts;
+
+	opts = kzalloc_obj(*opts);
+	if (!opts)
+		return -ENOMEM;
+
+	/* Set mount options defaults */
+	opts->s_uid = current_uid();
+	opts->s_gid = current_gid();
+	opts->s_dmask = opts->s_fmask = current_umask();
+
+	fc->fs_private = opts;
+	fc->ops = &omfs_context_ops;
+
+	return 0;
+}
+
+static void omfs_free_fc(struct fs_context *fc)
+{
+	kfree(fc->fs_private);
+}
+
+static struct file_system_type omfs_fs_type = {
+	.owner		 = THIS_MODULE,
+	.name		 = "omfs",
+	.kill_sb	 = kill_block_super,
+	.fs_flags	 = FS_REQUIRES_DEV,
+	.init_fs_context = omfs_init_fs_context,
+	.parameters	 = omfs_param_spec,
+};
+MODULE_ALIAS_FS("omfs");
+
+static int __init init_omfs_fs(void)
+{
+	return register_filesystem(&omfs_fs_type);
+}
+
+static void __exit exit_omfs_fs(void)
+{
+	unregister_filesystem(&omfs_fs_type);
+}
+
+module_init(init_omfs_fs);
+module_exit(exit_omfs_fs);