[GFS2] The core of GFS2

This patch contains all the core files for GFS2.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 1597 insertions, 0 deletions

diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
new file mode 100644
index 000000000000..1e6f51b74f44
--- /dev/null
+++ b/fs/gfs2/ops_file.c
@@ -0,0 +1,1597 @@
+/*
+ * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
+ * Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/pagemap.h>
+#include <linux/uio.h>
+#include <linux/blkdev.h>
+#include <linux/mm.h>
+#include <linux/smp_lock.h>
+#include <linux/gfs2_ioctl.h>
+#include <asm/semaphore.h>
+#include <asm/uaccess.h>
+
+#include "gfs2.h"
+#include "bmap.h"
+#include "dir.h"
+#include "glock.h"
+#include "glops.h"
+#include "inode.h"
+#include "jdata.h"
+#include "lm.h"
+#include "log.h"
+#include "meta_io.h"
+#include "ops_file.h"
+#include "ops_vm.h"
+#include "quota.h"
+#include "rgrp.h"
+#include "trans.h"
+
+/* "bad" is for NFS support */
+struct filldir_bad_entry {
+	char *fbe_name;
+	unsigned int fbe_length;
+	uint64_t fbe_offset;
+	struct gfs2_inum fbe_inum;
+	unsigned int fbe_type;
+};
+
+struct filldir_bad {
+	struct gfs2_sbd *fdb_sbd;
+
+	struct filldir_bad_entry *fdb_entry;
+	unsigned int fdb_entry_num;
+	unsigned int fdb_entry_off;
+
+	char *fdb_name;
+	unsigned int fdb_name_size;
+	unsigned int fdb_name_off;
+};
+
+/* For regular, non-NFS */
+struct filldir_reg {
+	struct gfs2_sbd *fdr_sbd;
+	int fdr_prefetch;
+
+	filldir_t fdr_filldir;
+	void *fdr_opaque;
+};
+
+typedef ssize_t(*do_rw_t) (struct file *file,
+		   char __user *buf,
+		   size_t size, loff_t *offset,
+		   unsigned int num_gh, struct gfs2_holder *ghs);
+
+/**
+ * gfs2_llseek - seek to a location in a file
+ * @file: the file
+ * @offset: the offset
+ * @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
+ *
+ * SEEK_END requires the glock for the file because it references the
+ * file's size.
+ *
+ * Returns: The new offset, or errno
+ */
+
+static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
+{
+	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
+	struct gfs2_holder i_gh;
+	loff_t error;
+
+	atomic_inc(&ip->i_sbd->sd_ops_file);
+
+	if (origin == 2) {
+		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
+					   &i_gh);
+		if (!error) {
+			error = remote_llseek(file, offset, origin);
+			gfs2_glock_dq_uninit(&i_gh);
+		}
+	} else
+		error = remote_llseek(file, offset, origin);
+
+	return error;
+}
+
+static inline unsigned int vma2state(struct vm_area_struct *vma)
+{
+	if ((vma->vm_flags & (VM_MAYWRITE | VM_MAYSHARE)) ==
+	    (VM_MAYWRITE | VM_MAYSHARE))
+		return LM_ST_EXCLUSIVE;
+	return LM_ST_SHARED;
+}
+
+static ssize_t walk_vm_hard(struct file *file, const char __user *buf, size_t size,
+		    loff_t *offset, do_rw_t operation)
+{
+	struct gfs2_holder *ghs;
+	unsigned int num_gh = 0;
+	ssize_t count;
+	struct super_block *sb = file->f_dentry->d_inode->i_sb;
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	unsigned long start = (unsigned long)buf;
+	unsigned long end = start + size;
+	int dumping = (current->flags & PF_DUMPCORE);
+	unsigned int x = 0;
+
+	for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
+		if (end <= vma->vm_start)
+			break;
+		if (vma->vm_file &&
+		    vma->vm_file->f_dentry->d_inode->i_sb == sb) {
+			num_gh++;
+		}
+	}
+
+	ghs = kcalloc((num_gh + 1), sizeof(struct gfs2_holder), GFP_KERNEL);
+	if (!ghs) {
+		if (!dumping)
+			up_read(&mm->mmap_sem);
+		return -ENOMEM;
+	}
+
+	for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
+		if (end <= vma->vm_start)
+			break;
+		if (vma->vm_file) {
+			struct inode *inode = vma->vm_file->f_dentry->d_inode;
+			if (inode->i_sb == sb)
+				gfs2_holder_init(get_v2ip(inode)->i_gl,
+						 vma2state(vma), 0, &ghs[x++]);
+		}
+	}
+
+	if (!dumping)
+		up_read(&mm->mmap_sem);
+
+	gfs2_assert(get_v2sdp(sb), x == num_gh);
+
+	count = operation(file, buf, size, offset, num_gh, ghs);
+
+	while (num_gh--)
+		gfs2_holder_uninit(&ghs[num_gh]);
+	kfree(ghs);
+
+	return count;
+}
+
+/**
+ * walk_vm - Walk the vmas associated with a buffer for read or write.
+ *    If any of them are gfs2, pass the gfs2 inode down to the read/write
+ *    worker function so that locks can be acquired in the correct order.
+ * @file: The file to read/write from/to
+ * @buf: The buffer to copy to/from
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ * @operation: The read or write worker function
+ *
+ * Outputs: Offset - updated according to number of bytes written
+ *
+ * Returns: The number of bytes written, errno on failure
+ */
+
+static ssize_t walk_vm(struct file *file, const char __user *buf, size_t size,
+	       loff_t *offset, do_rw_t operation)
+{
+	struct gfs2_holder gh;
+
+	if (current->mm) {
+		struct super_block *sb = file->f_dentry->d_inode->i_sb;
+		struct mm_struct *mm = current->mm;
+		struct vm_area_struct *vma;
+		unsigned long start = (unsigned long)buf;
+		unsigned long end = start + size;
+		int dumping = (current->flags & PF_DUMPCORE);
+
+		if (!dumping)
+			down_read(&mm->mmap_sem);
+
+		for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
+			if (end <= vma->vm_start)
+				break;
+			if (vma->vm_file &&
+			    vma->vm_file->f_dentry->d_inode->i_sb == sb)
+				goto do_locks;
+		}
+
+		if (!dumping)
+			up_read(&mm->mmap_sem);
+	}
+
+	return operation(file, buf, size, offset, 0, &gh);
+
+do_locks:
+	return walk_vm_hard(file, buf, size, offset, operation);
+}
+
+static ssize_t do_jdata_read(struct file *file, char __user *buf, size_t size,
+			     loff_t *offset)
+{
+	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
+	ssize_t count = 0;
+
+	if (*offset < 0)
+		return -EINVAL;
+	if (!access_ok(VERIFY_WRITE, buf, size))
+		return -EFAULT;
+
+	if (!(file->f_flags & O_LARGEFILE)) {
+		if (*offset >= MAX_NON_LFS)
+			return -EFBIG;
+		if (*offset + size > MAX_NON_LFS)
+			size = MAX_NON_LFS - *offset;
+	}
+
+	count = gfs2_jdata_read(ip, buf, *offset, size, gfs2_copy2user);
+
+	if (count > 0)
+		*offset += count;
+
+	return count;
+}
+
+/**
+ * do_read_direct - Read bytes from a file
+ * @file: The file to read from
+ * @buf: The buffer to copy into
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ * @num_gh: The number of other locks we need to do the read
+ * @ghs: the locks we need plus one for our lock
+ *
+ * Outputs: Offset - updated according to number of bytes read
+ *
+ * Returns: The number of bytes read, errno on failure
+ */
+
+static ssize_t do_read_direct(struct file *file, char __user *buf, size_t size,
+			      loff_t *offset, unsigned int num_gh,
+			      struct gfs2_holder *ghs)
+{
+	struct inode *inode = file->f_mapping->host;
+	struct gfs2_inode *ip = get_v2ip(inode);
+	unsigned int state = LM_ST_DEFERRED;
+	int flags = 0;
+	unsigned int x;
+	ssize_t count = 0;
+	int error;
+
+	for (x = 0; x < num_gh; x++)
+		if (ghs[x].gh_gl == ip->i_gl) {
+			state = LM_ST_SHARED;
+			flags |= GL_LOCAL_EXCL;
+			break;
+		}
+
+	gfs2_holder_init(ip->i_gl, state, flags, &ghs[num_gh]);
+
+	error = gfs2_glock_nq_m(num_gh + 1, ghs);
+	if (error)
+		goto out;
+
+	error = -EINVAL;
+	if (gfs2_is_jdata(ip))
+		goto out_gunlock;
+
+	if (gfs2_is_stuffed(ip)) {
+		size_t mask = bdev_hardsect_size(inode->i_sb->s_bdev) - 1;
+
+		if (((*offset) & mask) || (((unsigned long)buf) & mask))
+			goto out_gunlock;
+
+		count = do_jdata_read(file, buf, size & ~mask, offset);
+	} else
+		count = generic_file_read(file, buf, size, offset);
+
+	error = 0;
+
+ out_gunlock:
+	gfs2_glock_dq_m(num_gh + 1, ghs);
+
+ out:
+	gfs2_holder_uninit(&ghs[num_gh]);
+
+	return (count) ? count : error;
+}
+
+/**
+ * do_read_buf - Read bytes from a file
+ * @file: The file to read from
+ * @buf: The buffer to copy into
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ * @num_gh: The number of other locks we need to do the read
+ * @ghs: the locks we need plus one for our lock
+ *
+ * Outputs: Offset - updated according to number of bytes read
+ *
+ * Returns: The number of bytes read, errno on failure
+ */
+
+static ssize_t do_read_buf(struct file *file, char __user *buf, size_t size,
+			   loff_t *offset, unsigned int num_gh,
+			   struct gfs2_holder *ghs)
+{
+	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
+	ssize_t count = 0;
+	int error;
+
+	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &ghs[num_gh]);
+
+	error = gfs2_glock_nq_m_atime(num_gh + 1, ghs);
+	if (error)
+		goto out;
+
+	if (gfs2_is_jdata(ip))
+		count = do_jdata_read(file, buf, size, offset);
+	else
+		count = generic_file_read(file, buf, size, offset);
+
+	gfs2_glock_dq_m(num_gh + 1, ghs);
+
+ out:
+	gfs2_holder_uninit(&ghs[num_gh]);
+
+	return (count) ? count : error;
+}
+
+/**
+ * gfs2_read - Read bytes from a file
+ * @file: The file to read from
+ * @buf: The buffer to copy into
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ *
+ * Outputs: Offset - updated according to number of bytes read
+ *
+ * Returns: The number of bytes read, errno on failure
+ */
+
+static ssize_t gfs2_read(struct file *file, char __user *buf, size_t size,
+			 loff_t *offset)
+{
+	atomic_inc(&get_v2sdp(file->f_mapping->host->i_sb)->sd_ops_file);
+
+	if (file->f_flags & O_DIRECT)
+		return walk_vm(file, buf, size, offset, do_read_direct);
+	else
+		return walk_vm(file, buf, size, offset, do_read_buf);
+}
+
+/**
+ * grope_mapping - feel up a mapping that needs to be written
+ * @buf: the start of the memory to be written
+ * @size: the size of the memory to be written
+ *
+ * We do this after acquiring the locks on the mapping,
+ * but before starting the write transaction.  We need to make
+ * sure that we don't cause recursive transactions if blocks
+ * need to be allocated to the file backing the mapping.
+ *
+ * Returns: errno
+ */
+
+static int grope_mapping(const char __user *buf, size_t size)
+{
+	const char __user *stop = buf + size;
+	char c;
+
+	while (buf < stop) {
+		if (copy_from_user(&c, buf, 1))
+			return -EFAULT;
+		buf += PAGE_CACHE_SIZE;
+		buf = (const char __user *)PAGE_ALIGN((unsigned long)buf);
+	}
+
+	return 0;
+}
+
+/**
+ * do_write_direct_alloc - Write bytes to a file
+ * @file: The file to write to
+ * @buf: The buffer to copy from
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ *
+ * Outputs: Offset - updated according to number of bytes written
+ *
+ * Returns: The number of bytes written, errno on failure
+ */
+
+static ssize_t do_write_direct_alloc(struct file *file, const char __user *buf, size_t size,
+				     loff_t *offset)
+{
+	struct inode *inode = file->f_mapping->host;
+	struct gfs2_inode *ip = get_v2ip(inode);
+	struct gfs2_sbd *sdp = ip->i_sbd;
+	struct gfs2_alloc *al = NULL;
+	struct iovec local_iov = { .iov_base = buf, .iov_len = size };
+	struct buffer_head *dibh;
+	unsigned int data_blocks, ind_blocks;
+	ssize_t count;
+	int error;
+
+	gfs2_write_calc_reserv(ip, size, &data_blocks, &ind_blocks);
+
+	al = gfs2_alloc_get(ip);
+
+	error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
+	if (error)
+		goto fail;
+
+	error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
+	if (error)
+		goto fail_gunlock_q;
+
+	al->al_requested = data_blocks + ind_blocks;
+
+	error = gfs2_inplace_reserve(ip);
+	if (error)
+		goto fail_gunlock_q;
+
+	error = gfs2_trans_begin(sdp,
+				 al->al_rgd->rd_ri.ri_length + ind_blocks +
+				 RES_DINODE + RES_STATFS + RES_QUOTA, 0);
+	if (error)
+		goto fail_ipres;
+
+	if ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)) {
+		error = gfs2_meta_inode_buffer(ip, &dibh);
+		if (error)
+			goto fail_end_trans;
+
+		ip->i_di.di_mode &= (ip->i_di.di_mode & S_IXGRP) ?
+			(~(S_ISUID | S_ISGID)) : (~S_ISUID);
+
+		gfs2_trans_add_bh(ip->i_gl, dibh);
+		gfs2_dinode_out(&ip->i_di, dibh->b_data);
+		brelse(dibh);
+	}
+
+	if (gfs2_is_stuffed(ip)) {
+		error = gfs2_unstuff_dinode(ip, gfs2_unstuffer_sync, NULL);
+		if (error)
+			goto fail_end_trans;
+	}
+
+	count = generic_file_write_nolock(file, &local_iov, 1, offset);
+	if (count < 0) {
+		error = count;
+		goto fail_end_trans;
+	}
+
+	error = gfs2_meta_inode_buffer(ip, &dibh);
+	if (error)
+		goto fail_end_trans;
+
+	if (ip->i_di.di_size < inode->i_size)
+		ip->i_di.di_size = inode->i_size;
+	ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
+
+	gfs2_trans_add_bh(ip->i_gl, dibh);
+	gfs2_dinode_out(&ip->i_di, dibh->b_data);
+	brelse(dibh);
+
+	gfs2_trans_end(sdp);
+
+	if (file->f_flags & O_SYNC)
+		gfs2_log_flush_glock(ip->i_gl);
+
+	gfs2_inplace_release(ip);
+	gfs2_quota_unlock(ip);
+	gfs2_alloc_put(ip);
+
+	if (file->f_mapping->nrpages) {
+		error = filemap_fdatawrite(file->f_mapping);
+		if (!error)
+			error = filemap_fdatawait(file->f_mapping);
+	}
+	if (error)
+		return error;
+
+	return count;
+
+ fail_end_trans:
+	gfs2_trans_end(sdp);
+
+ fail_ipres:
+	gfs2_inplace_release(ip);
+
+ fail_gunlock_q:
+	gfs2_quota_unlock(ip);
+
+ fail:
+	gfs2_alloc_put(ip);
+
+	return error;
+}
+
+/**
+ * do_write_direct - Write bytes to a file
+ * @file: The file to write to
+ * @buf: The buffer to copy from
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ * @num_gh: The number of other locks we need to do the read
+ * @gh: the locks we need plus one for our lock
+ *
+ * Outputs: Offset - updated according to number of bytes written
+ *
+ * Returns: The number of bytes written, errno on failure
+ */
+
+static ssize_t do_write_direct(struct file *file, const char __user *buf, size_t size,
+			       loff_t *offset, unsigned int num_gh,
+			       struct gfs2_holder *ghs)
+{
+	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
+	struct gfs2_sbd *sdp = ip->i_sbd;
+	struct gfs2_file *fp = get_v2fp(file);
+	unsigned int state = LM_ST_DEFERRED;
+	int alloc_required;
+	unsigned int x;
+	size_t s;
+	ssize_t count = 0;
+	int error;
+
+	if (test_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags))
+		state = LM_ST_EXCLUSIVE;
+	else
+		for (x = 0; x < num_gh; x++)
+			if (ghs[x].gh_gl == ip->i_gl) {
+				state = LM_ST_EXCLUSIVE;
+				break;
+			}
+
+ restart:
+	gfs2_holder_init(ip->i_gl, state, 0, &ghs[num_gh]);
+
+	error = gfs2_glock_nq_m(num_gh + 1, ghs);
+	if (error)
+		goto out;
+
+	error = -EINVAL;
+	if (gfs2_is_jdata(ip))
+		goto out_gunlock;
+
+	if (num_gh) {
+		error = grope_mapping(buf, size);
+		if (error)
+			goto out_gunlock;
+	}
+
+	if (file->f_flags & O_APPEND)
+		*offset = ip->i_di.di_size;
+
+	if (!(file->f_flags & O_LARGEFILE)) {
+		error = -EFBIG;
+		if (*offset >= MAX_NON_LFS)
+			goto out_gunlock;
+		if (*offset + size > MAX_NON_LFS)
+			size = MAX_NON_LFS - *offset;
+	}
+
+	if (gfs2_is_stuffed(ip) ||
+	    *offset + size > ip->i_di.di_size ||
+	    ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)))
+		alloc_required = 1;
+	else {
+		error = gfs2_write_alloc_required(ip, *offset, size,
+						 &alloc_required);
+		if (error)
+			goto out_gunlock;
+	}
+
+	if (alloc_required && state != LM_ST_EXCLUSIVE) {
+		gfs2_glock_dq_m(num_gh + 1, ghs);
+		gfs2_holder_uninit(&ghs[num_gh]);
+		state = LM_ST_EXCLUSIVE;
+		goto restart;
+	}
+
+	if (alloc_required) {
+		set_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags);
+
+		/* split large writes into smaller atomic transactions */
+		while (size) {
+			s = gfs2_tune_get(sdp, gt_max_atomic_write);
+			if (s > size)
+				s = size;
+
+			error = do_write_direct_alloc(file, buf, s, offset);
+			if (error < 0)
+				goto out_gunlock;
+
+			buf += error;
+			size -= error;
+			count += error;
+		}
+	} else {
+		struct iovec local_iov = { .iov_base = buf, .iov_len = size };
+		struct gfs2_holder t_gh;
+
+		clear_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags);
+
+		error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
+					   GL_NEVER_RECURSE, &t_gh);
+		if (error)
+			goto out_gunlock;
+
+		count = generic_file_write_nolock(file, &local_iov, 1, offset);
+
+		gfs2_glock_dq_uninit(&t_gh);
+	}
+
+	error = 0;
+
+ out_gunlock:
+	gfs2_glock_dq_m(num_gh + 1, ghs);
+
+ out:
+	gfs2_holder_uninit(&ghs[num_gh]);
+
+	return (count) ? count : error;
+}
+
+/**
+ * do_do_write_buf - Write bytes to a file
+ * @file: The file to write to
+ * @buf: The buffer to copy from
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ *
+ * Outputs: Offset - updated according to number of bytes written
+ *
+ * Returns: The number of bytes written, errno on failure
+ */
+
+static ssize_t do_do_write_buf(struct file *file, const char __user *buf, size_t size,
+			       loff_t *offset)
+{
+	struct inode *inode = file->f_mapping->host;
+	struct gfs2_inode *ip = get_v2ip(inode);
+	struct gfs2_sbd *sdp = ip->i_sbd;
+	struct gfs2_alloc *al = NULL;
+	struct buffer_head *dibh;
+	unsigned int data_blocks, ind_blocks;
+	int alloc_required, journaled;
+	ssize_t count;
+	int error;
+
+	journaled = gfs2_is_jdata(ip);
+
+	gfs2_write_calc_reserv(ip, size, &data_blocks, &ind_blocks);
+
+	error = gfs2_write_alloc_required(ip, *offset, size, &alloc_required);
+	if (error)
+		return error;
+
+	if (alloc_required) {
+		al = gfs2_alloc_get(ip);
+
+		error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
+		if (error)
+			goto fail;
+
+		error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
+		if (error)
+			goto fail_gunlock_q;
+
+		al->al_requested = data_blocks + ind_blocks;
+
+		error = gfs2_inplace_reserve(ip);
+		if (error)
+			goto fail_gunlock_q;
+
+		error = gfs2_trans_begin(sdp,
+					 al->al_rgd->rd_ri.ri_length +
+					 ind_blocks +
+					 ((journaled) ? data_blocks : 0) +
+					 RES_DINODE + RES_STATFS + RES_QUOTA,
+					 0);
+		if (error)
+			goto fail_ipres;
+	} else {
+		error = gfs2_trans_begin(sdp,
+					((journaled) ? data_blocks : 0) +
+					RES_DINODE,
+					0);
+		if (error)
+			goto fail_ipres;
+	}
+
+	if ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)) {
+		error = gfs2_meta_inode_buffer(ip, &dibh);
+		if (error)
+			goto fail_end_trans;
+
+		ip->i_di.di_mode &= (ip->i_di.di_mode & S_IXGRP) ?
+					  (~(S_ISUID | S_ISGID)) : (~S_ISUID);
+
+		gfs2_trans_add_bh(ip->i_gl, dibh);
+		gfs2_dinode_out(&ip->i_di, dibh->b_data);
+		brelse(dibh);
+	}
+
+	if (journaled) {
+		count = gfs2_jdata_write(ip, buf, *offset, size,
+					 gfs2_copy_from_user);
+		if (count < 0) {
+			error = count;
+			goto fail_end_trans;
+		}
+
+		*offset += count;
+	} else {
+		struct iovec local_iov = { .iov_base = buf, .iov_len = size };
+
+		count = generic_file_write_nolock(file, &local_iov, 1, offset);
+		if (count < 0) {
+			error = count;
+			goto fail_end_trans;
+		}
+
+		error = gfs2_meta_inode_buffer(ip, &dibh);
+		if (error)
+			goto fail_end_trans;
+
+		if (ip->i_di.di_size < inode->i_size)
+			ip->i_di.di_size = inode->i_size;
+		ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
+
+		gfs2_trans_add_bh(ip->i_gl, dibh);
+		gfs2_dinode_out(&ip->i_di, dibh->b_data);
+		brelse(dibh);
+	}
+
+	gfs2_trans_end(sdp);
+
+	if (file->f_flags & O_SYNC || IS_SYNC(inode)) {
+		gfs2_log_flush_glock(ip->i_gl);
+		error = filemap_fdatawrite(file->f_mapping);
+		if (error == 0)
+			error = filemap_fdatawait(file->f_mapping);
+		if (error)
+			goto fail_ipres;
+	}
+
+	if (alloc_required) {
+		gfs2_assert_warn(sdp, count != size ||
+				 al->al_alloced);
+		gfs2_inplace_release(ip);
+		gfs2_quota_unlock(ip);
+		gfs2_alloc_put(ip);
+	}
+
+	return count;
+
+ fail_end_trans:
+	gfs2_trans_end(sdp);
+
+ fail_ipres:
+	if (alloc_required)
+		gfs2_inplace_release(ip);
+
+ fail_gunlock_q:
+	if (alloc_required)
+		gfs2_quota_unlock(ip);
+
+ fail:
+	if (alloc_required)
+		gfs2_alloc_put(ip);
+
+	return error;
+}
+
+/**
+ * do_write_buf - Write bytes to a file
+ * @file: The file to write to
+ * @buf: The buffer to copy from
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ * @num_gh: The number of other locks we need to do the read
+ * @gh: the locks we need plus one for our lock
+ *
+ * Outputs: Offset - updated according to number of bytes written
+ *
+ * Returns: The number of bytes written, errno on failure
+ */
+
+static ssize_t do_write_buf(struct file *file, const char __user *buf, size_t size,
+			    loff_t *offset, unsigned int num_gh,
+			    struct gfs2_holder *ghs)
+{
+	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
+	struct gfs2_sbd *sdp = ip->i_sbd;
+	size_t s;
+	ssize_t count = 0;
+	int error;
+
+	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ghs[num_gh]);
+
+	error = gfs2_glock_nq_m(num_gh + 1, ghs);
+	if (error)
+		goto out;
+
+	if (num_gh) {
+		error = grope_mapping(buf, size);
+		if (error)
+			goto out_gunlock;
+	}
+
+	if (file->f_flags & O_APPEND)
+		*offset = ip->i_di.di_size;
+
+	if (!(file->f_flags & O_LARGEFILE)) {
+		error = -EFBIG;
+		if (*offset >= MAX_NON_LFS)
+			goto out_gunlock;
+		if (*offset + size > MAX_NON_LFS)
+			size = MAX_NON_LFS - *offset;
+	}
+
+	/* split large writes into smaller atomic transactions */
+	while (size) {
+		s = gfs2_tune_get(sdp, gt_max_atomic_write);
+		if (s > size)
+			s = size;
+
+		error = do_do_write_buf(file, buf, s, offset);
+		if (error < 0)
+			goto out_gunlock;
+
+		buf += error;
+		size -= error;
+		count += error;
+	}
+
+	error = 0;
+
+ out_gunlock:
+	gfs2_glock_dq_m(num_gh + 1, ghs);
+
+ out:
+	gfs2_holder_uninit(&ghs[num_gh]);
+
+	return (count) ? count : error;
+}
+
+/**
+ * gfs2_write - Write bytes to a file
+ * @file: The file to write to
+ * @buf: The buffer to copy from
+ * @size: The amount of data requested
+ * @offset: The current file offset
+ *
+ * Outputs: Offset - updated according to number of bytes written
+ *
+ * Returns: The number of bytes written, errno on failure
+ */
+
+static ssize_t gfs2_write(struct file *file, const char __user *buf,
+			  size_t size, loff_t *offset)
+{
+	struct inode *inode = file->f_mapping->host;
+	ssize_t count;
+
+	atomic_inc(&get_v2sdp(inode->i_sb)->sd_ops_file);
+
+	if (*offset < 0)
+		return -EINVAL;
+	if (!access_ok(VERIFY_READ, buf, size))
+		return -EFAULT;
+
+	mutex_lock(&inode->i_mutex);
+	if (file->f_flags & O_DIRECT)
+		count = walk_vm(file, buf, size, offset,
+				do_write_direct);
+	else
+		count = walk_vm(file, buf, size, offset, do_write_buf);
+	mutex_unlock(&inode->i_mutex);
+
+	return count;
+}
+
+/**
+ * filldir_reg_func - Report a directory entry to the caller of gfs2_dir_read()
+ * @opaque: opaque data used by the function
+ * @name: the name of the directory entry
+ * @length: the length of the name
+ * @offset: the entry's offset in the directory
+ * @inum: the inode number the entry points to
+ * @type: the type of inode the entry points to
+ *
+ * Returns: 0 on success, 1 if buffer full
+ */
+
+static int filldir_reg_func(void *opaque, const char *name, unsigned int length,
+			    uint64_t offset, struct gfs2_inum *inum,
+			    unsigned int type)
+{
+	struct filldir_reg *fdr = (struct filldir_reg *)opaque;
+	struct gfs2_sbd *sdp = fdr->fdr_sbd;
+	int error;
+
+	error = fdr->fdr_filldir(fdr->fdr_opaque, name, length, offset,
+				 inum->no_formal_ino, type);
+	if (error)
+		return 1;
+
+	if (fdr->fdr_prefetch && !(length == 1 && *name == '.')) {
+		gfs2_glock_prefetch_num(sdp,
+				       inum->no_addr, &gfs2_inode_glops,
+				       LM_ST_SHARED, LM_FLAG_TRY | LM_FLAG_ANY);
+		gfs2_glock_prefetch_num(sdp,
+				       inum->no_addr, &gfs2_iopen_glops,
+				       LM_ST_SHARED, LM_FLAG_TRY);
+	}
+
+	return 0;
+}
+
+/**
+ * readdir_reg - Read directory entries from a directory
+ * @file: The directory to read from
+ * @dirent: Buffer for dirents
+ * @filldir: Function used to do the copying
+ *
+ * Returns: errno
+ */
+
+static int readdir_reg(struct file *file, void *dirent, filldir_t filldir)
+{
+	struct gfs2_inode *dip = get_v2ip(file->f_mapping->host);
+	struct filldir_reg fdr;
+	struct gfs2_holder d_gh;
+	uint64_t offset = file->f_pos;
+	int error;
+
+	fdr.fdr_sbd = dip->i_sbd;
+	fdr.fdr_prefetch = 1;
+	fdr.fdr_filldir = filldir;
+	fdr.fdr_opaque = dirent;
+
+	gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
+	error = gfs2_glock_nq_atime(&d_gh);
+	if (error) {
+		gfs2_holder_uninit(&d_gh);
+		return error;
+	}
+
+	error = gfs2_dir_read(dip, &offset, &fdr, filldir_reg_func);
+
+	gfs2_glock_dq_uninit(&d_gh);
+
+	file->f_pos = offset;
+
+	return error;
+}
+
+/**
+ * filldir_bad_func - Report a directory entry to the caller of gfs2_dir_read()
+ * @opaque: opaque data used by the function
+ * @name: the name of the directory entry
+ * @length: the length of the name
+ * @offset: the entry's offset in the directory
+ * @inum: the inode number the entry points to
+ * @type: the type of inode the entry points to
+ *
+ * For supporting NFS.
+ *
+ * Returns: 0 on success, 1 if buffer full
+ */
+
+static int filldir_bad_func(void *opaque, const char *name, unsigned int length,
+			    uint64_t offset, struct gfs2_inum *inum,
+			    unsigned int type)
+{
+	struct filldir_bad *fdb = (struct filldir_bad *)opaque;
+	struct gfs2_sbd *sdp = fdb->fdb_sbd;
+	struct filldir_bad_entry *fbe;
+
+	if (fdb->fdb_entry_off == fdb->fdb_entry_num ||
+	    fdb->fdb_name_off + length > fdb->fdb_name_size)
+		return 1;
+
+	fbe = &fdb->fdb_entry[fdb->fdb_entry_off];
+	fbe->fbe_name = fdb->fdb_name + fdb->fdb_name_off;
+	memcpy(fbe->fbe_name, name, length);
+	fbe->fbe_length = length;
+	fbe->fbe_offset = offset;
+	fbe->fbe_inum = *inum;
+	fbe->fbe_type = type;
+
+	fdb->fdb_entry_off++;
+	fdb->fdb_name_off += length;
+
+	if (!(length == 1 && *name == '.')) {
+		gfs2_glock_prefetch_num(sdp,
+				       inum->no_addr, &gfs2_inode_glops,
+				       LM_ST_SHARED, LM_FLAG_TRY | LM_FLAG_ANY);
+		gfs2_glock_prefetch_num(sdp,
+				       inum->no_addr, &gfs2_iopen_glops,
+				       LM_ST_SHARED, LM_FLAG_TRY);
+	}
+
+	return 0;
+}
+
+/**
+ * readdir_bad - Read directory entries from a directory
+ * @file: The directory to read from
+ * @dirent: Buffer for dirents
+ * @filldir: Function used to do the copying
+ *
+ * For supporting NFS.
+ *
+ * Returns: errno
+ */
+
+static int readdir_bad(struct file *file, void *dirent, filldir_t filldir)
+{
+	struct gfs2_inode *dip = get_v2ip(file->f_mapping->host);
+	struct gfs2_sbd *sdp = dip->i_sbd;
+	struct filldir_reg fdr;
+	unsigned int entries, size;
+	struct filldir_bad *fdb;
+	struct gfs2_holder d_gh;
+	uint64_t offset = file->f_pos;
+	unsigned int x;
+	struct filldir_bad_entry *fbe;
+	int error;
+
+	entries = gfs2_tune_get(sdp, gt_entries_per_readdir);
+	size = sizeof(struct filldir_bad) +
+	    entries * (sizeof(struct filldir_bad_entry) + GFS2_FAST_NAME_SIZE);
+
+	fdb = kzalloc(size, GFP_KERNEL);
+	if (!fdb)
+		return -ENOMEM;
+
+	fdb->fdb_sbd = sdp;
+	fdb->fdb_entry = (struct filldir_bad_entry *)(fdb + 1);
+	fdb->fdb_entry_num = entries;
+	fdb->fdb_name = ((char *)fdb) + sizeof(struct filldir_bad) +
+		entries * sizeof(struct filldir_bad_entry);
+	fdb->fdb_name_size = entries * GFS2_FAST_NAME_SIZE;
+
+	gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
+	error = gfs2_glock_nq_atime(&d_gh);
+	if (error) {
+		gfs2_holder_uninit(&d_gh);
+		goto out;
+	}
+
+	error = gfs2_dir_read(dip, &offset, fdb, filldir_bad_func);
+
+	gfs2_glock_dq_uninit(&d_gh);
+
+	fdr.fdr_sbd = sdp;
+	fdr.fdr_prefetch = 0;
+	fdr.fdr_filldir = filldir;
+	fdr.fdr_opaque = dirent;
+
+	for (x = 0; x < fdb->fdb_entry_off; x++) {
+		fbe = &fdb->fdb_entry[x];
+
+		error = filldir_reg_func(&fdr,
+					 fbe->fbe_name, fbe->fbe_length,
+					 fbe->fbe_offset,
+					 &fbe->fbe_inum, fbe->fbe_type);
+		if (error) {
+			file->f_pos = fbe->fbe_offset;
+			error = 0;
+			goto out;
+		}
+	}
+
+	file->f_pos = offset;
+
+ out:
+	kfree(fdb);
+
+	return error;
+}
+
+/**
+ * gfs2_readdir - Read directory entries from a directory
+ * @file: The directory to read from
+ * @dirent: Buffer for dirents
+ * @filldir: Function used to do the copying
+ *
+ * Returns: errno
+ */
+
+static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir)
+{
+	int error;
+
+	atomic_inc(&get_v2sdp(file->f_mapping->host->i_sb)->sd_ops_file);
+
+	if (strcmp(current->comm, "nfsd") != 0)
+		error = readdir_reg(file, dirent, filldir);
+	else
+		error = readdir_bad(file, dirent, filldir);
+
+	return error;
+}
+
+static int gfs2_ioctl_flags(struct gfs2_inode *ip, unsigned int cmd, unsigned long arg)
+{
+	unsigned int lmode = (cmd == GFS2_IOCTL_SETFLAGS) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
+	struct buffer_head *dibh;
+	struct gfs2_holder i_gh;
+	int error;
+	__u32 flags = 0, change;
+
+	if (cmd == GFS2_IOCTL_SETFLAGS) {
+		error = get_user(flags, (__u32 __user *)arg);
+		if (error)
+			return -EFAULT;
+	}
+
+	error = gfs2_glock_nq_init(ip->i_gl, lmode, 0, &i_gh);
+	if (error)
+		return error;
+
+	if (cmd == GFS2_IOCTL_SETFLAGS) {
+		change = flags ^ ip->i_di.di_flags;
+		error = -EPERM;
+		if (change & (GFS2_DIF_IMMUTABLE|GFS2_DIF_APPENDONLY)) {
+			if (!capable(CAP_LINUX_IMMUTABLE))
+				goto out;
+		}
+		error = -EINVAL;
+		if (flags & (GFS2_DIF_JDATA|GFS2_DIF_DIRECTIO)) {
+			if (!S_ISREG(ip->i_di.di_mode))
+				goto out;
+			/* FIXME: Would be nice not to require the following test */
+			if ((flags & GFS2_DIF_JDATA) && ip->i_di.di_size)
+				goto out;
+		}
+		if (flags & (GFS2_DIF_INHERIT_JDATA|GFS2_DIF_INHERIT_DIRECTIO)) {
+			if (!S_ISDIR(ip->i_di.di_mode))
+				goto out;
+		}
+
+		error = gfs2_trans_begin(ip->i_sbd, RES_DINODE, 0);
+		if (error)
+			goto out;
+
+		error = gfs2_meta_inode_buffer(ip, &dibh);
+		if (error)
+			goto out_trans_end;
+
+		ip->i_di.di_flags = flags;
+
+		gfs2_trans_add_bh(ip->i_gl, dibh);
+        	gfs2_dinode_out(&ip->i_di, dibh->b_data);
+
+        	brelse(dibh);
+
+out_trans_end:
+		gfs2_trans_end(ip->i_sbd);
+	} else {
+		flags = ip->i_di.di_flags;
+	}
+out:
+	gfs2_glock_dq_uninit(&i_gh);
+	if (cmd == GFS2_IOCTL_GETFLAGS) {
+		if (put_user(flags, (__u32 __user *)arg))
+			return -EFAULT;
+	}
+	return error;
+}
+
+/**
+ * gfs2_ioctl - do an ioctl on a file
+ * @inode: the inode
+ * @file: the file pointer
+ * @cmd: the ioctl command
+ * @arg: the argument
+ *
+ * Returns: errno
+ */
+
+static int gfs2_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+		      unsigned long arg)
+{
+	struct gfs2_inode *ip = get_v2ip(inode);
+
+	atomic_inc(&ip->i_sbd->sd_ops_file);
+
+	switch (cmd) {
+	case GFS2_IOCTL_IDENTIFY: {
+		unsigned int x = GFS2_MAGIC;
+		if (copy_to_user((unsigned int __user *)arg, &x, sizeof(unsigned int)))
+			return -EFAULT;
+		return 0;
+
+	case GFS2_IOCTL_SETFLAGS:
+	case GFS2_IOCTL_GETFLAGS:
+		return gfs2_ioctl_flags(ip, cmd, arg);
+	}
+
+	default:
+		return -ENOTTY;
+	}
+}
+
+/**
+ * gfs2_mmap -
+ * @file: The file to map
+ * @vma: The VMA which described the mapping
+ *
+ * Returns: 0 or error code
+ */
+
+static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
+	struct gfs2_holder i_gh;
+	int error;
+
+	atomic_inc(&ip->i_sbd->sd_ops_file);
+
+	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
+	error = gfs2_glock_nq_atime(&i_gh);
+	if (error) {
+		gfs2_holder_uninit(&i_gh);
+		return error;
+	}
+
+	if (gfs2_is_jdata(ip)) {
+		if (vma->vm_flags & VM_MAYSHARE)
+			error = -EOPNOTSUPP;
+		else
+			vma->vm_ops = &gfs2_vm_ops_private;
+	} else {
+		/* This is VM_MAYWRITE instead of VM_WRITE because a call
+		   to mprotect() can turn on VM_WRITE later. */
+
+		if ((vma->vm_flags & (VM_MAYSHARE | VM_MAYWRITE)) ==
+		    (VM_MAYSHARE | VM_MAYWRITE))
+			vma->vm_ops = &gfs2_vm_ops_sharewrite;
+		else
+			vma->vm_ops = &gfs2_vm_ops_private;
+	}
+
+	gfs2_glock_dq_uninit(&i_gh);
+
+	return error;
+}
+
+/**
+ * gfs2_open - open a file
+ * @inode: the inode to open
+ * @file: the struct file for this opening
+ *
+ * Returns: errno
+ */
+
+static int gfs2_open(struct inode *inode, struct file *file)
+{
+	struct gfs2_inode *ip = get_v2ip(inode);
+	struct gfs2_holder i_gh;
+	struct gfs2_file *fp;
+	int error;
+
+	atomic_inc(&ip->i_sbd->sd_ops_file);
+
+	fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
+	if (!fp)
+		return -ENOMEM;
+
+	init_MUTEX(&fp->f_fl_mutex);
+
+	fp->f_inode = ip;
+	fp->f_vfile = file;
+
+	gfs2_assert_warn(ip->i_sbd, !get_v2fp(file));
+	set_v2fp(file, fp);
+
+	if (S_ISREG(ip->i_di.di_mode)) {
+		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
+					   &i_gh);
+		if (error)
+			goto fail;
+
+		if (!(file->f_flags & O_LARGEFILE) &&
+		    ip->i_di.di_size > MAX_NON_LFS) {
+			error = -EFBIG;
+			goto fail_gunlock;
+		}
+
+		/* Listen to the Direct I/O flag */
+
+		if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
+			file->f_flags |= O_DIRECT;
+
+		/* Don't let the user open O_DIRECT on a jdata file */
+
+		if ((file->f_flags & O_DIRECT) && gfs2_is_jdata(ip)) {
+			error = -EINVAL;
+			goto fail_gunlock;
+		}
+
+		gfs2_glock_dq_uninit(&i_gh);
+	}
+
+	return 0;
+
+ fail_gunlock:
+	gfs2_glock_dq_uninit(&i_gh);
+
+ fail:
+	set_v2fp(file, NULL);
+	kfree(fp);
+
+	return error;
+}
+
+/**
+ * gfs2_close - called to close a struct file
+ * @inode: the inode the struct file belongs to
+ * @file: the struct file being closed
+ *
+ * Returns: errno
+ */
+
+static int gfs2_close(struct inode *inode, struct file *file)
+{
+	struct gfs2_sbd *sdp = get_v2sdp(inode->i_sb);
+	struct gfs2_file *fp;
+
+	atomic_inc(&sdp->sd_ops_file);
+
+	fp = get_v2fp(file);
+	set_v2fp(file, NULL);
+
+	if (gfs2_assert_warn(sdp, fp))
+		return -EIO;
+
+	kfree(fp);
+
+	return 0;
+}
+
+/**
+ * gfs2_fsync - sync the dirty data for a file (across the cluster)
+ * @file: the file that points to the dentry (we ignore this)
+ * @dentry: the dentry that points to the inode to sync
+ *
+ * Returns: errno
+ */
+
+static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+	struct gfs2_inode *ip = get_v2ip(dentry->d_inode);
+
+	atomic_inc(&ip->i_sbd->sd_ops_file);
+	gfs2_log_flush_glock(ip->i_gl);
+
+	return 0;
+}
+
+/**
+ * gfs2_lock - acquire/release a posix lock on a file
+ * @file: the file pointer
+ * @cmd: either modify or retrieve lock state, possibly wait
+ * @fl: type and range of lock
+ *
+ * Returns: errno
+ */
+
+static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
+{
+	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
+	struct gfs2_sbd *sdp = ip->i_sbd;
+	struct lm_lockname name =
+		{ .ln_number = ip->i_num.no_addr,
+		  .ln_type = LM_TYPE_PLOCK };
+
+	atomic_inc(&sdp->sd_ops_file);
+
+	if (!(fl->fl_flags & FL_POSIX))
+		return -ENOLCK;
+	if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
+		return -ENOLCK;
+
+	if (sdp->sd_args.ar_localflocks) {
+		if (IS_GETLK(cmd)) {
+			struct file_lock *tmp;
+			lock_kernel();
+			tmp = posix_test_lock(file, fl);
+			fl->fl_type = F_UNLCK;
+			if (tmp)
+				memcpy(fl, tmp, sizeof(struct file_lock));
+			unlock_kernel();
+			return 0;
+		} else {
+			int error;
+			lock_kernel();
+			error = posix_lock_file_wait(file, fl);
+			unlock_kernel();
+			return error;
+		}
+	}
+
+	if (IS_GETLK(cmd))
+		return gfs2_lm_plock_get(sdp, &name, file, fl);
+	else if (fl->fl_type == F_UNLCK)
+		return gfs2_lm_punlock(sdp, &name, file, fl);
+	else
+		return gfs2_lm_plock(sdp, &name, file, cmd, fl);
+}
+
+/**
+ * gfs2_sendfile - Send bytes to a file or socket
+ * @in_file: The file to read from
+ * @out_file: The file to write to
+ * @count: The amount of data
+ * @offset: The beginning file offset
+ *
+ * Outputs: offset - updated according to number of bytes read
+ *
+ * Returns: The number of bytes sent, errno on failure
+ */
+
+static ssize_t gfs2_sendfile(struct file *in_file, loff_t *offset, size_t count,
+			     read_actor_t actor, void *target)
+{
+	struct gfs2_inode *ip = get_v2ip(in_file->f_mapping->host);
+	struct gfs2_holder gh;
+	ssize_t retval;
+
+	atomic_inc(&ip->i_sbd->sd_ops_file);
+
+	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
+
+	retval = gfs2_glock_nq_atime(&gh);
+	if (retval)
+		goto out;
+
+	if (gfs2_is_jdata(ip))
+		retval = -EOPNOTSUPP;
+	else
+		retval = generic_file_sendfile(in_file, offset, count, actor,
+					       target);
+
+	gfs2_glock_dq(&gh);
+
+ out:
+	gfs2_holder_uninit(&gh);
+
+	return retval;
+}
+
+static int do_flock(struct file *file, int cmd, struct file_lock *fl)
+{
+	struct gfs2_file *fp = get_v2fp(file);
+	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
+	struct gfs2_inode *ip = fp->f_inode;
+	struct gfs2_glock *gl;
+	unsigned int state;
+	int flags;
+	int error = 0;
+
+	state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
+	flags = ((IS_SETLKW(cmd)) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
+
+	down(&fp->f_fl_mutex);
+
+	gl = fl_gh->gh_gl;
+	if (gl) {
+		if (fl_gh->gh_state == state)
+			goto out;
+		gfs2_glock_hold(gl);
+		flock_lock_file_wait(file,
+				     &(struct file_lock){.fl_type = F_UNLCK});		
+		gfs2_glock_dq_uninit(fl_gh);
+	} else {
+		error = gfs2_glock_get(ip->i_sbd,
+				      ip->i_num.no_addr, &gfs2_flock_glops,
+				      CREATE, &gl);
+		if (error)
+			goto out;
+	}
+
+	gfs2_holder_init(gl, state, flags, fl_gh);
+	gfs2_glock_put(gl);
+
+	error = gfs2_glock_nq(fl_gh);
+	if (error) {
+		gfs2_holder_uninit(fl_gh);
+		if (error == GLR_TRYFAILED)
+			error = -EAGAIN;
+	} else {
+		error = flock_lock_file_wait(file, fl);
+		gfs2_assert_warn(ip->i_sbd, !error);
+	}
+
+ out:
+	up(&fp->f_fl_mutex);
+
+	return error;
+}
+
+static void do_unflock(struct file *file, struct file_lock *fl)
+{
+	struct gfs2_file *fp = get_v2fp(file);
+	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
+
+	down(&fp->f_fl_mutex);
+	flock_lock_file_wait(file, fl);
+	if (fl_gh->gh_gl)
+		gfs2_glock_dq_uninit(fl_gh);
+	up(&fp->f_fl_mutex);
+}
+
+/**
+ * gfs2_flock - acquire/release a flock lock on a file
+ * @file: the file pointer
+ * @cmd: either modify or retrieve lock state, possibly wait
+ * @fl: type and range of lock
+ *
+ * Returns: errno
+ */
+
+static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
+{
+	struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
+	struct gfs2_sbd *sdp = ip->i_sbd;
+
+	atomic_inc(&ip->i_sbd->sd_ops_file);
+
+	if (!(fl->fl_flags & FL_FLOCK))
+		return -ENOLCK;
+	if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
+		return -ENOLCK;
+
+	if (sdp->sd_args.ar_localflocks)
+		return flock_lock_file_wait(file, fl);
+
+	if (fl->fl_type == F_UNLCK) {
+		do_unflock(file, fl);
+		return 0;
+	} else
+		return do_flock(file, cmd, fl);
+}
+
+struct file_operations gfs2_file_fops = {
+	.llseek = gfs2_llseek,
+	.read = gfs2_read,
+	.write = gfs2_write,
+	.ioctl = gfs2_ioctl,
+	.mmap = gfs2_mmap,
+	.open = gfs2_open,
+	.release = gfs2_close,
+	.fsync = gfs2_fsync,
+	.lock = gfs2_lock,
+	.sendfile = gfs2_sendfile,
+	.flock = gfs2_flock,
+};
+
+struct file_operations gfs2_dir_fops = {
+	.readdir = gfs2_readdir,
+	.ioctl = gfs2_ioctl,
+	.open = gfs2_open,
+	.release = gfs2_close,
+	.fsync = gfs2_fsync,
+	.lock = gfs2_lock,
+	.flock = gfs2_flock,
+};
+