ocfs2: Use own splice write actor

We need to fill holes during a splice write. Provide our own splice write
actor which can call ocfs2_file_buffered_write() with a splice-specific
callback.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
This commit is contained in:
Mark Fasheh 2007-03-06 17:24:46 -08:00
parent fa41045fcb
commit 6af67d8205
3 changed files with 162 additions and 1 deletions

View file

@ -25,6 +25,7 @@
#include <linux/pagemap.h>
#include <asm/byteorder.h>
#include <linux/swap.h>
#include <linux/pipe_fs_i.h>
#define MLOG_MASK_PREFIX ML_FILE_IO
#include <cluster/masklog.h>
@ -748,6 +749,74 @@ int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
return ret;
}
/*
* This will copy user data from the buffer page in the splice
* context.
*
* For now, we ignore SPLICE_F_MOVE as that would require some extra
* communication out all the way to ocfs2_write().
*/
int ocfs2_map_and_write_splice_data(struct inode *inode,
struct ocfs2_write_ctxt *wc, u64 *p_blkno,
unsigned int *ret_from, unsigned int *ret_to)
{
int ret;
unsigned int to, from, cluster_start, cluster_end;
char *src, *dst;
struct ocfs2_splice_write_priv *sp = wc->w_private;
struct pipe_buffer *buf = sp->s_buf;
unsigned long bytes, src_from;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
ocfs2_figure_cluster_boundaries(osb, wc->w_cpos, &cluster_start,
&cluster_end);
from = sp->s_offset;
src_from = sp->s_buf_offset;
bytes = wc->w_count;
if (wc->w_large_pages) {
/*
* For cluster size < page size, we have to
* calculate pos within the cluster and obey
* the rightmost boundary.
*/
bytes = min(bytes, (unsigned long)(osb->s_clustersize
- (wc->w_pos & (osb->s_clustersize - 1))));
}
to = from + bytes;
if (wc->w_this_page_new)
ret = ocfs2_map_page_blocks(wc->w_this_page, p_blkno, inode,
cluster_start, cluster_end, 1);
else
ret = ocfs2_map_page_blocks(wc->w_this_page, p_blkno, inode,
from, to, 0);
if (ret) {
mlog_errno(ret);
goto out;
}
BUG_ON(from > PAGE_CACHE_SIZE);
BUG_ON(to > PAGE_CACHE_SIZE);
BUG_ON(from > osb->s_clustersize);
BUG_ON(to > osb->s_clustersize);
src = buf->ops->map(sp->s_pipe, buf, 1);
dst = kmap_atomic(wc->w_this_page, KM_USER1);
memcpy(dst + from, src + src_from, bytes);
kunmap_atomic(wc->w_this_page, KM_USER1);
buf->ops->unmap(sp->s_pipe, buf, src);
wc->w_finished_copy = 1;
*ret_from = from;
*ret_to = to;
out:
return bytes ? (unsigned int)bytes : ret;
}
/*
* This will copy user data from the iovec in the buffered write
* context.

View file

@ -80,6 +80,20 @@ int ocfs2_map_and_write_user_data(struct inode *inode,
unsigned int *ret_from,
unsigned int *ret_to);
struct ocfs2_splice_write_priv {
struct splice_desc *s_sd;
struct pipe_buffer *s_buf;
struct pipe_inode_info *s_pipe;
/* Neither offset value is ever larger than one page */
unsigned int s_offset;
unsigned int s_buf_offset;
};
int ocfs2_map_and_write_splice_data(struct inode *inode,
struct ocfs2_write_ctxt *wc,
u64 *p_blkno,
unsigned int *ret_from,
unsigned int *ret_to);
/* all ocfs2_dio_end_io()'s fault */
#define ocfs2_iocb_is_rw_locked(iocb) \
test_bit(0, (unsigned long *)&iocb->private)

View file

@ -1603,6 +1603,84 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
return written ? written : ret;
}
static int ocfs2_splice_write_actor(struct pipe_inode_info *pipe,
struct pipe_buffer *buf,
struct splice_desc *sd)
{
int ret, count, total = 0;
ssize_t copied = 0;
struct ocfs2_splice_write_priv sp;
ret = buf->ops->pin(pipe, buf);
if (ret)
goto out;
sp.s_sd = sd;
sp.s_buf = buf;
sp.s_pipe = pipe;
sp.s_offset = sd->pos & ~PAGE_CACHE_MASK;
sp.s_buf_offset = buf->offset;
count = sd->len;
if (count + sp.s_offset > PAGE_CACHE_SIZE)
count = PAGE_CACHE_SIZE - sp.s_offset;
do {
/*
* splice wants us to copy up to one page at a
* time. For pagesize > cluster size, this means we
* might enter ocfs2_buffered_write_cluster() more
* than once, so keep track of our progress here.
*/
copied = ocfs2_buffered_write_cluster(sd->file,
(loff_t)sd->pos + total,
count,
ocfs2_map_and_write_splice_data,
&sp);
if (copied < 0) {
mlog_errno(copied);
ret = copied;
goto out;
}
count -= copied;
sp.s_offset += copied;
sp.s_buf_offset += copied;
total += copied;
} while (count);
ret = 0;
out:
return total ? total : 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;
ret = __splice_from_pipe(pipe, out, ppos, len, flags,
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,
@ -1633,7 +1711,7 @@ static ssize_t ocfs2_file_splice_write(struct pipe_inode_info *pipe,
}
/* ok, we're done with i_size and alloc work */
ret = generic_file_splice_write_nolock(pipe, out, ppos, len, flags);
ret = __ocfs2_file_splice_write(pipe, out, ppos, len, flags);
out_unlock:
ocfs2_rw_unlock(inode, 1);