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Switch gfs2 to nd_set_link()

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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2010-01-14 00:59:16 -05:00
parent 8737c9305b
commit c177c2ac8c
1 changed files with 44 additions and 103 deletions
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147
fs/gfs2/ops_inode.c
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@ -975,103 +975,12 @@ out:
return error;
}
/**
* gfs2_readlinki - return the contents of a symlink
* @ip: the symlink's inode
* @buf: a pointer to the buffer to be filled
* @len: a pointer to the length of @buf
*
* If @buf is too small, a piece of memory is kmalloc()ed and needs
* to be freed by the caller.
*
* Returns: errno
*/
static int gfs2_readlinki(struct gfs2_inode *ip, char **buf, unsigned int *len)
{
struct gfs2_holder i_gh;
struct buffer_head *dibh;
unsigned int x;
int error;
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
error = gfs2_glock_nq(&i_gh);
if (error) {
gfs2_holder_uninit(&i_gh);
return error;
}
if (!ip->i_disksize) {
gfs2_consist_inode(ip);
error = -EIO;
goto out;
}
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto out;
x = ip->i_disksize + 1;
if (x > *len) {
*buf = kmalloc(x, GFP_NOFS);
if (!*buf) {
error = -ENOMEM;
goto out_brelse;
}
}
memcpy(*buf, dibh->b_data + sizeof(struct gfs2_dinode), x);
*len = x;
out_brelse:
brelse(dibh);
out:
gfs2_glock_dq_uninit(&i_gh);
return error;
}
/**
* gfs2_readlink - Read the value of a symlink
* @dentry: the symlink
* @buf: the buffer to read the symlink data into
* @size: the size of the buffer
*
* Returns: errno
*/
static int gfs2_readlink(struct dentry *dentry, char __user *user_buf,
int user_size)
{
struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
char array[GFS2_FAST_NAME_SIZE], *buf = array;
unsigned int len = GFS2_FAST_NAME_SIZE;
int error;
error = gfs2_readlinki(ip, &buf, &len);
if (error)
return error;
if (user_size > len - 1)
user_size = len - 1;
if (copy_to_user(user_buf, buf, user_size))
error = -EFAULT;
else
error = user_size;
if (buf != array)
kfree(buf);
return error;
}
/**
* gfs2_follow_link - Follow a symbolic link
* @dentry: The dentry of the link
* @nd: Data that we pass to vfs_follow_link()
*
* This can handle symlinks of any size. It is optimised for symlinks
* under GFS2_FAST_NAME_SIZE.
* This can handle symlinks of any size.
*
* Returns: 0 on success or error code
*/
@ -1079,19 +988,50 @@ static int gfs2_readlink(struct dentry *dentry, char __user *user_buf,
static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
{
struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
char array[GFS2_FAST_NAME_SIZE], *buf = array;
unsigned int len = GFS2_FAST_NAME_SIZE;
struct gfs2_holder i_gh;
struct buffer_head *dibh;
unsigned int x;
char *buf;
int error;
error = gfs2_readlinki(ip, &buf, &len);
if (!error) {
error = vfs_follow_link(nd, buf);
if (buf != array)
kfree(buf);
} else
path_put(&nd->path);
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
error = gfs2_glock_nq(&i_gh);
if (error) {
gfs2_holder_uninit(&i_gh);
nd_set_link(nd, ERR_PTR(error));
return NULL;
}
return ERR_PTR(error);
if (!ip->i_disksize) {
gfs2_consist_inode(ip);
buf = ERR_PTR(-EIO);
goto out;
}
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error) {
buf = ERR_PTR(error);
goto out;
}
x = ip->i_disksize + 1;
buf = kmalloc(x, GFP_NOFS);
if (!buf)
buf = ERR_PTR(-ENOMEM);
else
memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), x);
brelse(dibh);
out:
gfs2_glock_dq_uninit(&i_gh);
nd_set_link(nd, buf);
return NULL;
}
static void gfs2_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
{
char *s = nd_get_link(nd);
if (!IS_ERR(s))
kfree(s);
}
/**
@ -1426,8 +1366,9 @@ const struct inode_operations gfs2_dir_iops = {
};
const struct inode_operations gfs2_symlink_iops = {
.readlink = gfs2_readlink,
.readlink = generic_readlink,
.follow_link = gfs2_follow_link,
.put_link = gfs2_put_link,
.permission = gfs2_permission,
.setattr = gfs2_setattr,
.getattr = gfs2_getattr,