Commit 067c054f authored by Al Viro's avatar Al Viro
Browse files

dlmfs: clean up dlmfs_file_{read,write}() a bit 



The damn file is constant-sized - 64 bytes.  IOW,
	* i_size_read() is pointless
	* so's dynamic allocation
	* so's the 'size' argument of user_dlm_read_lvb()
	* ... and so's open-coding simple_read_from_buffer(), while we are at it.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent b3a9e3b9

fs/ocfs2/dlmfs/dlmfs.c

+8 −44
Original line number Diff line number Diff line
@@ -221,47 +221,17 @@ static __poll_t dlmfs_file_poll(struct file *file, poll_table *wait) 
	return event;

}



static ssize_t dlmfs_file_read(struct file *filp,

static ssize_t dlmfs_file_read(struct file *file,

			       char __user *buf,

			       size_t count,

			       loff_t *ppos)

{

	int bytes_left;

	ssize_t got;

	char *lvb_buf;

	struct inode *inode = file_inode(filp);



	mlog(0, "inode %lu, count = %zu, *ppos = %llu\n",

		inode->i_ino, count, *ppos);

	char lvb[DLM_LVB_LEN];



	if (*ppos >= i_size_read(inode))

	if (!user_dlm_read_lvb(file_inode(file), lvb))

		return 0;



	/* don't read past the lvb */

	if (count > i_size_read(inode) - *ppos)

		count = i_size_read(inode) - *ppos;



	if (!count)

		return 0;



	lvb_buf = kmalloc(count, GFP_NOFS);

	if (!lvb_buf)

		return -ENOMEM;



	got = user_dlm_read_lvb(inode, lvb_buf, count);

	if (got) {

		BUG_ON(got != count);

		bytes_left = copy_to_user(buf, lvb_buf, count);

		count -= bytes_left;

	} else

		count = 0;



	kfree(lvb_buf);



	*ppos = *ppos + count;



	mlog(0, "read %zu bytes\n", count);

	return count;

	return simple_read_from_buffer(buf, count, ppos, lvb, sizeof(lvb));

}



static ssize_t dlmfs_file_write(struct file *filp,
@@ -269,34 +239,28 @@ static ssize_t dlmfs_file_write(struct file *filp, 
				size_t count,

				loff_t *ppos)

{

	char lvb_buf[DLM_LVB_LEN];

	int bytes_left;

	char *lvb_buf;

	struct inode *inode = file_inode(filp);



	mlog(0, "inode %lu, count = %zu, *ppos = %llu\n",

		inode->i_ino, count, *ppos);



	if (*ppos >= i_size_read(inode))

	if (*ppos >= DLM_LVB_LEN)

		return -ENOSPC;



	/* don't write past the lvb */

	if (count > i_size_read(inode) - *ppos)

		count = i_size_read(inode) - *ppos;

	if (count > DLM_LVB_LEN - *ppos)

		count = DLM_LVB_LEN - *ppos;



	if (!count)

		return 0;



	lvb_buf = kmalloc(count, GFP_NOFS);

	if (!lvb_buf)

		return -ENOMEM;



	bytes_left = copy_from_user(lvb_buf, buf, count);

	count -= bytes_left;

	if (count)

		user_dlm_write_lvb(inode, lvb_buf, count);



	kfree(lvb_buf);



	*ppos = *ppos + count;

	mlog(0, "wrote %zu bytes\n", count);

	return count;

fs/ocfs2/dlmfs/userdlm.c

+4 −8
Original line number Diff line number Diff line
@@ -547,24 +547,20 @@ void user_dlm_write_lvb(struct inode *inode, 
	spin_unlock(&lockres->l_lock);

}



ssize_t user_dlm_read_lvb(struct inode *inode,

			  char *val,

			  unsigned int len)

bool user_dlm_read_lvb(struct inode *inode, char *val)

{

	struct user_lock_res *lockres = &DLMFS_I(inode)->ip_lockres;

	char *lvb;

	ssize_t ret = len;



	BUG_ON(len > DLM_LVB_LEN);

	bool ret = true;



	spin_lock(&lockres->l_lock);



	BUG_ON(lockres->l_level < DLM_LOCK_PR);

	if (ocfs2_dlm_lvb_valid(&lockres->l_lksb)) {

		lvb = ocfs2_dlm_lvb(&lockres->l_lksb);

		memcpy(val, lvb, len);

		memcpy(val, lvb, DLM_LVB_LEN);

	} else

		ret = 0;

		ret = false;



	spin_unlock(&lockres->l_lock);

	return ret;

fs/ocfs2/dlmfs/userdlm.h

+1 −3
Original line number Diff line number Diff line
@@ -66,9 +66,7 @@ void user_dlm_cluster_unlock(struct user_lock_res *lockres, 
void user_dlm_write_lvb(struct inode *inode,

			const char *val,

			unsigned int len);

ssize_t user_dlm_read_lvb(struct inode *inode,

			  char *val,

			  unsigned int len);

bool user_dlm_read_lvb(struct inode *inode, char *val);

struct ocfs2_cluster_connection *user_dlm_register(const struct qstr *name);

void user_dlm_unregister(struct ocfs2_cluster_connection *conn);

void user_dlm_set_locking_protocol(void);