Ejemplo n.º 1
0
/**
 * vfs_fsync - perform a fsync or fdatasync on a file
 * @file:		file to sync
 * @datasync:		only perform a fdatasync operation
 *
 * Write back data and metadata for @file to disk.  If @datasync is
 * set only metadata needed to access modified file data is written.
 */
int vfs_fsync(struct file *file, int datasync)
{
	if (!fsync_enabled)
			return 0;

	return vfs_fsync_range(file, 0, LLONG_MAX, datasync);
}
Ejemplo n.º 2
0
static int wrapfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
	int err;
	struct file *lower_file;
	struct path lower_path;
	struct dentry *dentry = file->f_path.dentry;

#ifdef EXTRA_CREDIT
	if(wrapfs_get_debug(file->f_dentry->d_sb) & DEBUG_FILE)
		DEBUG_MESG("Enter");
#endif

	err = generic_file_fsync(file, start, end, datasync);
	if (err)
		goto out;
	lower_file = wrapfs_lower_file(file);
	wrapfs_get_lower_path(dentry, &lower_path);
	err = vfs_fsync_range(lower_file, start, end, datasync);
	wrapfs_put_lower_path(dentry, &lower_path);
out:

#ifdef EXTRA_CREDIT
	if(wrapfs_get_debug(file->f_dentry->d_sb) & DEBUG_FILE)
		DEBUG_RETURN("Exit", err);
#endif

	return err;
}
Ejemplo n.º 3
0
/**
 * vfs_fsync - perform a fsync or fdatasync on a file
 * @file:		file to sync
 * @datasync:		only perform a fdatasync operation
 *
 * Write back data and metadata for @file to disk.  If @datasync is
 * set only metadata needed to access modified file data is written.
 */
int vfs_fsync(struct file *file, int datasync)
{
	#ifdef CONFIG_FSYNC_OFF
		return 0;
	#endif
	return vfs_fsync_range(file, 0, LLONG_MAX, datasync);
}
Ejemplo n.º 4
0
/**
 * generic_write_sync - perform syncing after a write if file / inode is sync
 * @file:	file to which the write happened
 * @pos:	offset where the write started
 * @count:	length of the write
 *
 * This is just a simple wrapper about our general syncing function.
 */
int generic_write_sync(struct file *file, loff_t pos, loff_t count)
{
	if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
		return 0;
	return vfs_fsync_range(file, pos, pos + count - 1,
			       (file->f_flags & __O_SYNC) ? 0 : 1);
}
Ejemplo n.º 5
0
/**
 * vfs_fsync - perform a fsync or fdatasync on a file
 * @file:		file to sync
 * @datasync:		only perform a fdatasync operation
 *
 * Write back data and metadata for @file to disk.  If @datasync is
 * set only metadata needed to access modified file data is written.
 */
int vfs_fsync(struct file *file, int datasync)
{
#ifdef CONFIG_FSYNC_CONTROL
	if (!fsynccontrol_fsync_enabled())
		return 0;
#endif
	return vfs_fsync_range(file, 0, LLONG_MAX, datasync);
}
Ejemplo n.º 6
0
/**
 * vfs_fsync - perform a fsync or fdatasync on a file
 * @file:		file to sync
 * @datasync:		only perform a fdatasync operation
 *
 * Write back data and metadata for @file to disk.  If @datasync is
 * set only metadata needed to access modified file data is written.
 */
int vfs_fsync(struct file *file, int datasync)
{
	//conditional fsync disable
	#ifdef CONFIG_FSYNC_OFF
	  return 0;
	#endif
	return vfs_fsync_range(file, 0, LLONG_MAX, datasync);
}
Ejemplo n.º 7
0
/**
 * generic_write_sync - perform syncing after a write if file / inode is sync
 * @file:	file to which the write happened
 * @pos:	offset where the write started
 * @count:	length of the write
 *
 * This is just a simple wrapper about our general syncing function.
 */
int generic_write_sync(struct file *file, loff_t pos, loff_t count)
{
#ifdef CONFIG_FSYNC_CONTROL
	if (!fsynccontrol_fsync_enabled())
		return 0;
#endif
	if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
		return 0;
	return vfs_fsync_range(file, pos, pos + count - 1,
			       (file->f_flags & __O_SYNC) ? 0 : 1);
}
Ejemplo n.º 8
0
/**
 * generic_write_sync - perform syncing after a write if file / inode is sync
 * @file:	file to which the write happened
 * @pos:	offset where the write started
 * @count:	length of the write
 *
 * This is just a simple wrapper about our general syncing function.
 */
int generic_write_sync(struct file *file, loff_t pos, loff_t count)
{
	//conditional fsync disable
	#ifdef CONFIG_FSYNC_OFF
	  return 0;
	#endif
	if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
		return 0;
	return vfs_fsync_range(file, pos, pos + count - 1,
			       (file->f_flags & __O_SYNC) ? 0 : 1);
}
Ejemplo n.º 9
0
/**
 * generic_write_sync - perform syncing after a write if file / inode is sync
 * @file:	file to which the write happened
 * @pos:	offset where the write started
 * @count:	length of the write
 *
 * This is just a simple wrapper about our general syncing function.
 */
int generic_write_sync(struct file *file, loff_t pos, loff_t count)
{
#ifdef CONFIG_DYNAMIC_FSYNC
	if (!early_suspend_active)
		return 0;
#endif
	if (!(file->f_flags & O_DSYNC) && !IS_SYNC(file->f_mapping->host))
		return 0;
	return vfs_fsync_range(file, pos, pos + count - 1,
			       (file->f_flags & __O_SYNC) ? 0 : 1);
}
static int
ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
	int rc = 0;

	rc = generic_file_fsync(file, start, end, datasync);
	if (rc)
		goto out;
	rc = vfs_fsync_range(ecryptfs_file_to_lower(file), start, end,
			     datasync);
out:
	return rc;
}
Ejemplo n.º 11
0
static int
sdcardfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
	int err;
	struct file *lower_file;
	struct path lower_path;
	struct dentry *dentry = file->f_path.dentry;

	lower_file = sdcardfs_lower_file(file);
	sdcardfs_get_lower_path(dentry, &lower_path);
	err = vfs_fsync_range(lower_file, start, end, datasync);
	sdcardfs_put_lower_path(dentry, &lower_path);

	return err;
}
Ejemplo n.º 12
0
/*
 * WRITE Force Unit Access (FUA) emulation on a per struct se_task
 * LBA range basis..
 */
static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task)
{
	struct se_device *dev = cmd->se_dev;
	struct fd_dev *fd_dev = dev->dev_ptr;
	loff_t start = task->task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
	loff_t end = start + task->task_size;
	int ret;

	pr_debug("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n",
			task->task_lba, task->task_size);

	ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
	if (ret != 0)
		pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
}
Ejemplo n.º 13
0
static int wrapfs_fsync(struct file *file, loff_t start, loff_t end,
			int datasync)
{
	int err;
	struct file *lower_file;
	struct path lower_path;
	struct dentry *dentry = file->f_path.dentry;

	err = generic_file_fsync(file, start, end, datasync);
	if (err)
		goto out;
	lower_file = wrapfs_lower_file(file);
	wrapfs_get_lower_path(dentry, &lower_path);
	err = vfs_fsync_range(lower_file, start, end, datasync);
	wrapfs_put_lower_path(dentry, &lower_path);
out:
	return err;
}
Ejemplo n.º 14
0
Archivo: file.c Proyecto: Lyude/linux
static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
	struct fd real;
	const struct cred *old_cred;
	int ret;

	ret = ovl_real_fdget_meta(file, &real, !datasync);
	if (ret)
		return ret;

	/* Don't sync lower file for fear of receiving EROFS error */
	if (file_inode(real.file) == ovl_inode_upper(file_inode(file))) {
		old_cred = ovl_override_creds(file_inode(file)->i_sb);
		ret = vfs_fsync_range(real.file, start, end, datasync);
		revert_creds(old_cred);
	}

	fdput(real);

	return ret;
}
Ejemplo n.º 15
0
static void fd_emulate_sync_cache(struct se_task *task)
{
	struct se_cmd *cmd = task->task_se_cmd;
	struct se_device *dev = cmd->se_dev;
	struct fd_dev *fd_dev = dev->dev_ptr;
	int immed = (cmd->t_task_cdb[1] & 0x2);
	loff_t start, end;
	int ret;

	/*
	 * If the Immediate bit is set, queue up the GOOD response
	 * for this SYNCHRONIZE_CACHE op
	 */
	if (immed)
		transport_complete_sync_cache(cmd, 1);

	/*
	 * Determine if we will be flushing the entire device.
	 */
	if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
		start = 0;
		end = LLONG_MAX;
	} else {
		start = cmd->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size;
		if (cmd->data_length)
			end = start + cmd->data_length;
		else
			end = LLONG_MAX;
	}

	ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
	if (ret != 0)
		pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);

	if (!immed)
		transport_complete_sync_cache(cmd, ret == 0);
}
Ejemplo n.º 16
0
/**
 * vfs_fsync - perform a fsync or fdatasync on a file
 * @file:		file to sync
 * @datasync:		only perform a fdatasync operation
 *
 * Write back data and metadata for @file to disk.  If @datasync is
 * set only metadata needed to access modified file data is written.
 */
int vfs_fsync(struct file *file, int datasync)
{
	return vfs_fsync_range(file, 0, LLONG_MAX, datasync);
}
Ejemplo n.º 17
0
static int aio_submit(struct aio_output *output, struct aio_mref_aspect *mref_a, bool use_fdsync)
{
	struct mref_object *mref = mref_a->object;
	mm_segment_t oldfs;
	int res;
	struct iocb iocb = {
		.aio_data = (__u64)mref_a,
		.aio_lio_opcode = use_fdsync ? IOCB_CMD_FDSYNC : (mref->ref_rw != 0 ? IOCB_CMD_PWRITE : IOCB_CMD_PREAD),
		.aio_fildes = output->fd,
		.aio_buf = (unsigned long)mref->ref_data,
		.aio_nbytes = mref->ref_len,
		.aio_offset = mref->ref_pos,
		// .aio_reqprio = something(mref->ref_prio) field exists, but not yet implemented in kernelspace :(
	};
	struct iocb *iocbp = &iocb;
	unsigned long long latency;

	mars_trace(mref, "aio_submit");

	if (unlikely(output->fd < 0)) {
		MARS_ERR("bad fd = %d\n", output->fd);
		res = -EBADF;
		goto done;
	}

	oldfs = get_fs();
	set_fs(get_ds());
	latency = TIME_STATS(&timings[mref->ref_rw & 1], res = sys_io_submit(output->ctxp, 1, &iocbp));
	set_fs(oldfs);

	threshold_check(&aio_submit_threshold, latency);

	atomic_inc(&output->total_submit_count);

	if (likely(res >= 0)) {
		atomic_inc(&output->submit_count);
	} else if (likely(res == -EAGAIN)) {
		atomic_inc(&output->total_again_count);
	} else {
		MARS_ERR("error = %d\n", res);
	}

done:
	return res;
}

static int aio_submit_dummy(struct aio_output *output)
{
	mm_segment_t oldfs;
	int res;
	int dummy;
	struct iocb iocb = {
		.aio_buf = (__u64)&dummy,
	};
	struct iocb *iocbp = &iocb;

	oldfs = get_fs();
	set_fs(get_ds());
	res = sys_io_submit(output->ctxp, 1, &iocbp);
	set_fs(oldfs);

	if (likely(res >= 0)) {
		atomic_inc(&output->submit_count);
	}
	return res;
}

static
int aio_start_thread(
	struct aio_output *output,
	struct aio_threadinfo *tinfo,
	int(*fn)(void*),
	char class)
{
	int j;

	for (j = 0; j < MARS_PRIO_NR; j++) {
		INIT_LIST_HEAD(&tinfo->mref_list[j]);
	}
	tinfo->output = output;
	spin_lock_init(&tinfo->lock);
	init_waitqueue_head(&tinfo->event);
	init_waitqueue_head(&tinfo->terminate_event);
	tinfo->terminated = false;
	tinfo->thread = brick_thread_create(fn, tinfo, "mars_aio_%c%d", class, output->index);
	if (unlikely(!tinfo->thread)) {
		MARS_ERR("cannot create thread\n");
		return -ENOENT;
	}
	return 0;
}

static
void aio_stop_thread(struct aio_output *output, int i, bool do_submit_dummy)
{
	struct aio_threadinfo *tinfo = &output->tinfo[i];

	if (tinfo->thread) {
		MARS_DBG("stopping thread %d ...\n", i);
		brick_thread_stop_nowait(tinfo->thread);

		// workaround for waking up the receiver thread. TODO: check whether signal handlong could do better.
		if (do_submit_dummy) {
			MARS_DBG("submitting dummy for wakeup %d...\n", i);
			use_fake_mm();
			aio_submit_dummy(output);
			if (likely(current->mm)) {
				unuse_fake_mm();
			}
		}

		// wait for termination
		MARS_DBG("waiting for thread %d ...\n", i);
		wait_event_interruptible_timeout(
			tinfo->terminate_event,
			tinfo->terminated,
			(60 - i * 2) * HZ);
		if (likely(tinfo->terminated)) {
			brick_thread_stop(tinfo->thread);
		} else {
			MARS_ERR("thread %d did not terminate - leaving a zombie\n", i);
		}
	}
}

static
int aio_sync(struct file *file)
{
	int err;

	switch (aio_sync_mode) {
	case 1:
#if defined(S_BIAS) || (defined(RHEL_MAJOR) && (RHEL_MAJOR < 7))
		err = vfs_fsync_range(file, file->f_path.dentry, 0, LLONG_MAX, 1);
#else
		err = vfs_fsync_range(file, 0, LLONG_MAX, 1);
#endif
		break;
	case 2:
#if defined(S_BIAS) || (defined(RHEL_MAJOR) && (RHEL_MAJOR < 7))
		err = vfs_fsync_range(file, file->f_path.dentry, 0, LLONG_MAX, 0);
#else
		err = vfs_fsync_range(file, 0, LLONG_MAX, 0);
#endif
		break;
	default:
		err = filemap_write_and_wait_range(file->f_mapping, 0, LLONG_MAX);
	}

	return err;
}
Ejemplo n.º 18
0
static int gfs2_page_mkwrite(struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = file_inode(vmf->vma->vm_file);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_alloc_parms ap = { .aflags = 0, };
	unsigned long last_index;
	u64 pos = page->index << PAGE_SHIFT;
	unsigned int data_blocks, ind_blocks, rblocks;
	struct gfs2_holder gh;
	loff_t size;
	int ret;

	sb_start_pagefault(inode->i_sb);

	ret = gfs2_rsqa_alloc(ip);
	if (ret)
		goto out;

	gfs2_size_hint(vmf->vma->vm_file, pos, PAGE_SIZE);

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	ret = gfs2_glock_nq(&gh);
	if (ret)
		goto out_uninit;

	/* Update file times before taking page lock */
	file_update_time(vmf->vma->vm_file);

	set_bit(GLF_DIRTY, &ip->i_gl->gl_flags);
	set_bit(GIF_SW_PAGED, &ip->i_flags);

	if (!gfs2_write_alloc_required(ip, pos, PAGE_SIZE)) {
		lock_page(page);
		if (!PageUptodate(page) || page->mapping != inode->i_mapping) {
			ret = -EAGAIN;
			unlock_page(page);
		}
		goto out_unlock;
	}

	ret = gfs2_rindex_update(sdp);
	if (ret)
		goto out_unlock;

	gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
	ap.target = data_blocks + ind_blocks;
	ret = gfs2_quota_lock_check(ip, &ap);
	if (ret)
		goto out_unlock;
	ret = gfs2_inplace_reserve(ip, &ap);
	if (ret)
		goto out_quota_unlock;

	rblocks = RES_DINODE + ind_blocks;
	if (gfs2_is_jdata(ip))
		rblocks += data_blocks ? data_blocks : 1;
	if (ind_blocks || data_blocks) {
		rblocks += RES_STATFS + RES_QUOTA;
		rblocks += gfs2_rg_blocks(ip, data_blocks + ind_blocks);
	}
	ret = gfs2_trans_begin(sdp, rblocks, 0);
	if (ret)
		goto out_trans_fail;

	lock_page(page);
	ret = -EINVAL;
	size = i_size_read(inode);
	last_index = (size - 1) >> PAGE_SHIFT;
	/* Check page index against inode size */
	if (size == 0 || (page->index > last_index))
		goto out_trans_end;

	ret = -EAGAIN;
	/* If truncated, we must retry the operation, we may have raced
	 * with the glock demotion code.
	 */
	if (!PageUptodate(page) || page->mapping != inode->i_mapping)
		goto out_trans_end;

	/* Unstuff, if required, and allocate backing blocks for page */
	ret = 0;
	if (gfs2_is_stuffed(ip))
		ret = gfs2_unstuff_dinode(ip, page);
	if (ret == 0)
		ret = gfs2_allocate_page_backing(page);

out_trans_end:
	if (ret)
		unlock_page(page);
	gfs2_trans_end(sdp);
out_trans_fail:
	gfs2_inplace_release(ip);
out_quota_unlock:
	gfs2_quota_unlock(ip);
out_unlock:
	gfs2_glock_dq(&gh);
out_uninit:
	gfs2_holder_uninit(&gh);
	if (ret == 0) {
		set_page_dirty(page);
		wait_for_stable_page(page);
	}
out:
	sb_end_pagefault(inode->i_sb);
	return block_page_mkwrite_return(ret);
}

static const struct vm_operations_struct gfs2_vm_ops = {
	.fault = filemap_fault,
	.map_pages = filemap_map_pages,
	.page_mkwrite = gfs2_page_mkwrite,
};

/**
 * gfs2_mmap -
 * @file: The file to map
 * @vma: The VMA which described the mapping
 *
 * There is no need to get a lock here unless we should be updating
 * atime. We ignore any locking errors since the only consequence is
 * a missed atime update (which will just be deferred until later).
 *
 * Returns: 0
 */

static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);

	if (!(file->f_flags & O_NOATIME) &&
	    !IS_NOATIME(&ip->i_inode)) {
		struct gfs2_holder i_gh;
		int error;

		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
					   &i_gh);
		if (error)
			return error;
		/* grab lock to update inode */
		gfs2_glock_dq_uninit(&i_gh);
		file_accessed(file);
	}
	vma->vm_ops = &gfs2_vm_ops;

	return 0;
}

/**
 * gfs2_open_common - This is common to open and atomic_open
 * @inode: The inode being opened
 * @file: The file being opened
 *
 * This maybe called under a glock or not depending upon how it has
 * been called. We must always be called under a glock for regular
 * files, however. For other file types, it does not matter whether
 * we hold the glock or not.
 *
 * Returns: Error code or 0 for success
 */

int gfs2_open_common(struct inode *inode, struct file *file)
{
	struct gfs2_file *fp;
	int ret;

	if (S_ISREG(inode->i_mode)) {
		ret = generic_file_open(inode, file);
		if (ret)
			return ret;
	}

	fp = kzalloc(sizeof(struct gfs2_file), GFP_NOFS);
	if (!fp)
		return -ENOMEM;

	mutex_init(&fp->f_fl_mutex);

	gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
	file->private_data = fp;
	return 0;
}

/**
 * gfs2_open - open a file
 * @inode: the inode to open
 * @file: the struct file for this opening
 *
 * After atomic_open, this function is only used for opening files
 * which are already cached. We must still get the glock for regular
 * files to ensure that we have the file size uptodate for the large
 * file check which is in the common code. That is only an issue for
 * regular files though.
 *
 * Returns: errno
 */

static int gfs2_open(struct inode *inode, struct file *file)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder i_gh;
	int error;
	bool need_unlock = false;

	if (S_ISREG(ip->i_inode.i_mode)) {
		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
					   &i_gh);
		if (error)
			return error;
		need_unlock = true;
	}

	error = gfs2_open_common(inode, file);

	if (need_unlock)
		gfs2_glock_dq_uninit(&i_gh);

	return error;
}

/**
 * gfs2_release - 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_release(struct inode *inode, struct file *file)
{
	struct gfs2_inode *ip = GFS2_I(inode);

	kfree(file->private_data);
	file->private_data = NULL;

	if (!(file->f_mode & FMODE_WRITE))
		return 0;

	gfs2_rsqa_delete(ip, &inode->i_writecount);
	return 0;
}

/**
 * gfs2_fsync - sync the dirty data for a file (across the cluster)
 * @file: the file that points to the dentry
 * @start: the start position in the file to sync
 * @end: the end position in the file to sync
 * @datasync: set if we can ignore timestamp changes
 *
 * We split the data flushing here so that we don't wait for the data
 * until after we've also sent the metadata to disk. Note that for
 * data=ordered, we will write & wait for the data at the log flush
 * stage anyway, so this is unlikely to make much of a difference
 * except in the data=writeback case.
 *
 * If the fdatawrite fails due to any reason except -EIO, we will
 * continue the remainder of the fsync, although we'll still report
 * the error at the end. This is to match filemap_write_and_wait_range()
 * behaviour.
 *
 * Returns: errno
 */

static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
		      int datasync)
{
	struct address_space *mapping = file->f_mapping;
	struct inode *inode = mapping->host;
	int sync_state = inode->i_state & I_DIRTY_ALL;
	struct gfs2_inode *ip = GFS2_I(inode);
	int ret = 0, ret1 = 0;

	if (mapping->nrpages) {
		ret1 = filemap_fdatawrite_range(mapping, start, end);
		if (ret1 == -EIO)
			return ret1;
	}

	if (!gfs2_is_jdata(ip))
		sync_state &= ~I_DIRTY_PAGES;
	if (datasync)
		sync_state &= ~(I_DIRTY_SYNC | I_DIRTY_TIME);

	if (sync_state) {
		ret = sync_inode_metadata(inode, 1);
		if (ret)
			return ret;
		if (gfs2_is_jdata(ip))
			ret = file_write_and_wait(file);
		if (ret)
			return ret;
		gfs2_ail_flush(ip->i_gl, 1);
	}

	if (mapping->nrpages)
		ret = file_fdatawait_range(file, start, end);

	return ret ? ret : ret1;
}

/**
 * gfs2_file_write_iter - Perform a write to a file
 * @iocb: The io context
 * @iov: The data to write
 * @nr_segs: Number of @iov segments
 * @pos: The file position
 *
 * We have to do a lock/unlock here to refresh the inode size for
 * O_APPEND writes, otherwise we can land up writing at the wrong
 * offset. There is still a race, but provided the app is using its
 * own file locking, this will make O_APPEND work as expected.
 *
 */

static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
	struct file *file = iocb->ki_filp;
	struct gfs2_inode *ip = GFS2_I(file_inode(file));
	int ret;

	ret = gfs2_rsqa_alloc(ip);
	if (ret)
		return ret;

	gfs2_size_hint(file, iocb->ki_pos, iov_iter_count(from));

	if (iocb->ki_flags & IOCB_APPEND) {
		struct gfs2_holder gh;

		ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
		if (ret)
			return ret;
		gfs2_glock_dq_uninit(&gh);
	}

	return generic_file_write_iter(iocb, from);
}

static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len,
			   int mode)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct buffer_head *dibh;
	int error;
	unsigned int nr_blks;
	sector_t lblock = offset >> inode->i_blkbits;

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (unlikely(error))
		return error;

	gfs2_trans_add_meta(ip->i_gl, dibh);

	if (gfs2_is_stuffed(ip)) {
		error = gfs2_unstuff_dinode(ip, NULL);
		if (unlikely(error))
			goto out;
	}

	while (len) {
		struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
		bh_map.b_size = len;
		set_buffer_zeronew(&bh_map);

		error = gfs2_block_map(inode, lblock, &bh_map, 1);
		if (unlikely(error))
			goto out;
		len -= bh_map.b_size;
		nr_blks = bh_map.b_size >> inode->i_blkbits;
		lblock += nr_blks;
		if (!buffer_new(&bh_map))
			continue;
		if (unlikely(!buffer_zeronew(&bh_map))) {
			error = -EIO;
			goto out;
		}
	}
out:
	brelse(dibh);
	return error;
}
/**
 * calc_max_reserv() - Reverse of write_calc_reserv. Given a number of
 *                     blocks, determine how many bytes can be written.
 * @ip:          The inode in question.
 * @len:         Max cap of bytes. What we return in *len must be <= this.
 * @data_blocks: Compute and return the number of data blocks needed
 * @ind_blocks:  Compute and return the number of indirect blocks needed
 * @max_blocks:  The total blocks available to work with.
 *
 * Returns: void, but @len, @data_blocks and @ind_blocks are filled in.
 */
static void calc_max_reserv(struct gfs2_inode *ip, loff_t *len,
			    unsigned int *data_blocks, unsigned int *ind_blocks,
			    unsigned int max_blocks)
{
	loff_t max = *len;
	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
	unsigned int tmp, max_data = max_blocks - 3 * (sdp->sd_max_height - 1);

	for (tmp = max_data; tmp > sdp->sd_diptrs;) {
		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
		max_data -= tmp;
	}

	*data_blocks = max_data;
	*ind_blocks = max_blocks - max_data;
	*len = ((loff_t)max_data - 3) << sdp->sd_sb.sb_bsize_shift;
	if (*len > max) {
		*len = max;
		gfs2_write_calc_reserv(ip, max, data_blocks, ind_blocks);
	}
}

static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
{
	struct inode *inode = file_inode(file);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_alloc_parms ap = { .aflags = 0, };
	unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
	loff_t bytes, max_bytes, max_blks = UINT_MAX;
	int error;
	const loff_t pos = offset;
	const loff_t count = len;
	loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
	loff_t max_chunk_size = UINT_MAX & bsize_mask;

	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;

	offset &= bsize_mask;

	len = next - offset;
	bytes = sdp->sd_max_rg_data * sdp->sd_sb.sb_bsize / 2;
	if (!bytes)
		bytes = UINT_MAX;
	bytes &= bsize_mask;
	if (bytes == 0)
		bytes = sdp->sd_sb.sb_bsize;

	gfs2_size_hint(file, offset, len);

	gfs2_write_calc_reserv(ip, PAGE_SIZE, &data_blocks, &ind_blocks);
	ap.min_target = data_blocks + ind_blocks;

	while (len > 0) {
		if (len < bytes)
			bytes = len;
		if (!gfs2_write_alloc_required(ip, offset, bytes)) {
			len -= bytes;
			offset += bytes;
			continue;
		}

		/* We need to determine how many bytes we can actually
		 * fallocate without exceeding quota or going over the
		 * end of the fs. We start off optimistically by assuming
		 * we can write max_bytes */
		max_bytes = (len > max_chunk_size) ? max_chunk_size : len;

		/* Since max_bytes is most likely a theoretical max, we
		 * calculate a more realistic 'bytes' to serve as a good
		 * starting point for the number of bytes we may be able
		 * to write */
		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
		ap.target = data_blocks + ind_blocks;

		error = gfs2_quota_lock_check(ip, &ap);
		if (error)
			return error;
		/* ap.allowed tells us how many blocks quota will allow
		 * us to write. Check if this reduces max_blks */
		if (ap.allowed && ap.allowed < max_blks)
			max_blks = ap.allowed;

		error = gfs2_inplace_reserve(ip, &ap);
		if (error)
			goto out_qunlock;

		/* check if the selected rgrp limits our max_blks further */
		if (ap.allowed && ap.allowed < max_blks)
			max_blks = ap.allowed;

		/* Almost done. Calculate bytes that can be written using
		 * max_blks. We also recompute max_bytes, data_blocks and
		 * ind_blocks */
		calc_max_reserv(ip, &max_bytes, &data_blocks,
				&ind_blocks, max_blks);

		rblocks = RES_DINODE + ind_blocks + RES_STATFS + RES_QUOTA +
			  RES_RG_HDR + gfs2_rg_blocks(ip, data_blocks + ind_blocks);
		if (gfs2_is_jdata(ip))
			rblocks += data_blocks ? data_blocks : 1;

		error = gfs2_trans_begin(sdp, rblocks,
					 PAGE_SIZE/sdp->sd_sb.sb_bsize);
		if (error)
			goto out_trans_fail;

		error = fallocate_chunk(inode, offset, max_bytes, mode);
		gfs2_trans_end(sdp);

		if (error)
			goto out_trans_fail;

		len -= max_bytes;
		offset += max_bytes;
		gfs2_inplace_release(ip);
		gfs2_quota_unlock(ip);
	}

	if (!(mode & FALLOC_FL_KEEP_SIZE) && (pos + count) > inode->i_size) {
		i_size_write(inode, pos + count);
		file_update_time(file);
		mark_inode_dirty(inode);
	}

	if ((file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host))
		return vfs_fsync_range(file, pos, pos + count - 1,
			       (file->f_flags & __O_SYNC) ? 0 : 1);
	return 0;

out_trans_fail:
	gfs2_inplace_release(ip);
out_qunlock:
	gfs2_quota_unlock(ip);
	return error;
}

static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
{
	struct inode *inode = file_inode(file);
	struct gfs2_sbd *sdp = GFS2_SB(inode);
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder gh;
	int ret;

	if (mode & ~FALLOC_FL_KEEP_SIZE)
		return -EOPNOTSUPP;
	/* fallocate is needed by gfs2_grow to reserve space in the rindex */
	if (gfs2_is_jdata(ip) && inode != sdp->sd_rindex)
		return -EOPNOTSUPP;

	inode_lock(inode);

	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	ret = gfs2_glock_nq(&gh);
	if (ret)
		goto out_uninit;

	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
	    (offset + len) > inode->i_size) {
		ret = inode_newsize_ok(inode, offset + len);
		if (ret)
			goto out_unlock;
	}

	ret = get_write_access(inode);
	if (ret)
		goto out_unlock;

	ret = gfs2_rsqa_alloc(ip);
	if (ret)
		goto out_putw;

	ret = __gfs2_fallocate(file, mode, offset, len);
	if (ret)
		gfs2_rs_deltree(&ip->i_res);

out_putw:
	put_write_access(inode);
out_unlock:
	gfs2_glock_dq(&gh);
out_uninit:
	gfs2_holder_uninit(&gh);
	inode_unlock(inode);
	return ret;
}

static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe,
				      struct file *out, loff_t *ppos,
				      size_t len, unsigned int flags)
{
	int error;
	struct gfs2_inode *ip = GFS2_I(out->f_mapping->host);

	error = gfs2_rsqa_alloc(ip);
	if (error)
		return (ssize_t)error;

	gfs2_size_hint(out, *ppos, len);

	return iter_file_splice_write(pipe, out, ppos, len, flags);
}

#ifdef CONFIG_GFS2_FS_LOCKING_DLM

/**
 * 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 = GFS2_I(file->f_mapping->host);
	struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
	struct lm_lockstruct *ls = &sdp->sd_lockstruct;

	if (!(fl->fl_flags & FL_POSIX))
		return -ENOLCK;
	if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK)
		return -ENOLCK;

	if (cmd == F_CANCELLK) {
		/* Hack: */
		cmd = F_SETLK;
		fl->fl_type = F_UNLCK;
	}
	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
		if (fl->fl_type == F_UNLCK)
			locks_lock_file_wait(file, fl);
		return -EIO;
	}
	if (IS_GETLK(cmd))
		return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
	else if (fl->fl_type == F_UNLCK)
		return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
	else
		return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
}

static int do_flock(struct file *file, int cmd, struct file_lock *fl)
{
	struct gfs2_file *fp = file->private_data;
	struct gfs2_holder *fl_gh = &fp->f_fl_gh;
	struct gfs2_inode *ip = GFS2_I(file_inode(file));
	struct gfs2_glock *gl;
	unsigned int state;
	u16 flags;
	int error = 0;
	int sleeptime;

	state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
	flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY_1CB) | GL_EXACT;

	mutex_lock(&fp->f_fl_mutex);

	if (gfs2_holder_initialized(fl_gh)) {
		if (fl_gh->gh_state == state)
			goto out;
		locks_lock_file_wait(file,
				     &(struct file_lock) {
					     .fl_type = F_UNLCK,
					     .fl_flags = FL_FLOCK
				     });
		gfs2_glock_dq(fl_gh);
		gfs2_holder_reinit(state, flags, fl_gh);
	} else {