/**
* generic_file_splice_write_nolock - generic_file_splice_write without mutexes
* @pipe: pipe info
* @out: file to write to
* @len: number of bytes to splice
* @flags: splice modifier flags
*
* Will either move or copy pages (determined by @flags options) from
* the given pipe inode to the given file. The caller is responsible
* for acquiring i_mutex on both inodes.
*
*/
ssize_t
generic_file_splice_write_nolock(struct pipe_inode_info *pipe, struct file *out,
loff_t *ppos, size_t len, unsigned int flags)
{
struct address_space *mapping = out->f_mapping;
struct inode *inode = mapping->host;
ssize_t ret;
int err;
err = remove_suid(out->f_dentry);
if (unlikely(err))
return err;
ret = __splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_file);
if (ret > 0) {
*ppos += ret;
/*
* If file or inode is SYNC and we actually wrote some data,
* sync it.
*/
if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) {
err = generic_osync_inode(inode, mapping,
OSYNC_METADATA|OSYNC_DATA);
if (err)
ret = err;
}
}
return ret;
}
/**
* generic_file_splice_write_nolock - generic_file_splice_write without mutexes
* @pipe: pipe info
* @out: file to write to
* @len: number of bytes to splice
* @flags: splice modifier flags
*
* Will either move or copy pages (determined by @flags options) from
* the given pipe inode to the given file. The caller is responsible
* for acquiring i_mutex on both inodes.
*
*/
ssize_t
generic_file_splice_write_nolock(struct pipe_inode_info *pipe, struct file *out,
loff_t *ppos, size_t len, unsigned int flags)
{
struct address_space *mapping = out->f_mapping;
struct inode *inode = mapping->host;
ssize_t ret;
int err;
err = remove_suid(out->f_path.dentry);
if (unlikely(err))
return err;
ret = __splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_file);
if (ret > 0) {
unsigned long nr_pages;
*ppos += ret;
nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
/*
* If file or inode is SYNC and we actually wrote some data,
* sync it.
*/
if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) {
err = generic_osync_inode(inode, mapping,
OSYNC_METADATA|OSYNC_DATA);
if (err)
ret = err;
}
balance_dirty_pages_ratelimited_nr(mapping, nr_pages);
}
ssize_t splice_from_pipe(struct pipe_inode_info *pipe, struct file *out,
loff_t *ppos, size_t len, unsigned int flags,
splice_actor *actor)
{
ssize_t ret;
struct inode *inode = out->f_mapping->host;
/*
* The actor worker might be calling ->prepare_write and
* ->commit_write. Most of the time, these expect i_mutex to
* be held. Since this may result in an ABBA deadlock with
* pipe->inode, we have to order lock acquiry here.
*/
inode_double_lock(inode, pipe->inode);
ret = __splice_from_pipe(pipe, out, ppos, len, flags, actor);
inode_double_unlock(inode, pipe->inode);
return ret;
}
static ssize_t __ocfs2_file_splice_write(struct pipe_inode_info *pipe,
struct file *out,
loff_t *ppos,
size_t len,
unsigned int flags)
{
int ret, err;
struct address_space *mapping = out->f_mapping;
struct inode *inode = mapping->host;
struct splice_desc sd = {
.total_len = len,
.flags = flags,
.pos = *ppos,
.u.file = out,
};
ret = __splice_from_pipe(pipe, &sd, ocfs2_splice_write_actor);
if (ret > 0) {
*ppos += ret;
if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) {
err = generic_osync_inode(inode, mapping,
OSYNC_METADATA|OSYNC_DATA);
if (err)
ret = err;
}
}
return ret;
}
static ssize_t ocfs2_file_splice_write(struct pipe_inode_info *pipe,
struct file *out,
loff_t *ppos,
size_t len,
unsigned int flags)
{
int ret;
struct inode *inode = out->f_path.dentry->d_inode;
mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", out, pipe,
(unsigned int)len,
out->f_path.dentry->d_name.len,
out->f_path.dentry->d_name.name);
mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
ret = ocfs2_rw_lock(inode, 1);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
ret = ocfs2_prepare_inode_for_write(out->f_path.dentry, ppos, len, 0,
NULL);
if (ret < 0) {
mlog_errno(ret);
goto out_unlock;
}
if (pipe->inode)
mutex_lock_nested(&pipe->inode->i_mutex, I_MUTEX_CHILD);
/* ok, we're done with i_size and alloc work */
ret = __ocfs2_file_splice_write(pipe, out, ppos, len, flags);
if (pipe->inode)
mutex_unlock(&pipe->inode->i_mutex);
out_unlock:
ocfs2_rw_unlock(inode, 1);
out:
mutex_unlock(&inode->i_mutex);
mlog_exit(ret);
return ret;
}