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Diffstat (limited to 'fs/splice.c')
-rw-r--r--fs/splice.c74
1 files changed, 39 insertions, 35 deletions
diff --git a/fs/splice.c b/fs/splice.c
index 7fb04970c72..a285fd746dc 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -51,7 +51,7 @@ struct splice_pipe_desc {
* addition of remove_mapping(). If success is returned, the caller may
* attempt to reuse this page for another destination.
*/
-static int page_cache_pipe_buf_steal(struct pipe_inode_info *info,
+static int page_cache_pipe_buf_steal(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct page *page = buf->page;
@@ -78,16 +78,18 @@ static int page_cache_pipe_buf_steal(struct pipe_inode_info *info,
return 1;
}
+ buf->flags |= PIPE_BUF_FLAG_LRU;
return 0;
}
-static void page_cache_pipe_buf_release(struct pipe_inode_info *info,
+static void page_cache_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
page_cache_release(buf->page);
+ buf->flags &= ~PIPE_BUF_FLAG_LRU;
}
-static int page_cache_pipe_buf_pin(struct pipe_inode_info *info,
+static int page_cache_pipe_buf_pin(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
struct page *page = buf->page;
@@ -141,6 +143,7 @@ static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe,
if (!(buf->flags & PIPE_BUF_FLAG_GIFT))
return 1;
+ buf->flags |= PIPE_BUF_FLAG_LRU;
return generic_pipe_buf_steal(pipe, buf);
}
@@ -321,6 +324,8 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
mapping_gfp_mask(mapping));
if (unlikely(error)) {
page_cache_release(page);
+ if (error == -EEXIST)
+ continue;
break;
}
/*
@@ -497,14 +502,14 @@ EXPORT_SYMBOL(generic_file_splice_read);
* Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos'
* using sendpage(). Return the number of bytes sent.
*/
-static int pipe_to_sendpage(struct pipe_inode_info *info,
+static int pipe_to_sendpage(struct pipe_inode_info *pipe,
struct pipe_buffer *buf, struct splice_desc *sd)
{
struct file *file = sd->file;
loff_t pos = sd->pos;
int ret, more;
- ret = buf->ops->pin(info, buf);
+ ret = buf->ops->pin(pipe, buf);
if (!ret) {
more = (sd->flags & SPLICE_F_MORE) || sd->len < sd->total_len;
@@ -535,7 +540,7 @@ static int pipe_to_sendpage(struct pipe_inode_info *info,
* SPLICE_F_MOVE isn't set, or we cannot move the page, we simply create
* a new page in the output file page cache and fill/dirty that.
*/
-static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf,
+static int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
struct splice_desc *sd)
{
struct file *file = sd->file;
@@ -549,7 +554,7 @@ static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf,
/*
* make sure the data in this buffer is uptodate
*/
- ret = buf->ops->pin(info, buf);
+ ret = buf->ops->pin(pipe, buf);
if (unlikely(ret))
return ret;
@@ -566,37 +571,23 @@ static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf,
*/
if ((sd->flags & SPLICE_F_MOVE) && this_len == PAGE_CACHE_SIZE) {
/*
- * If steal succeeds, buf->page is now pruned from the vm
- * side (page cache) and we can reuse it. The page will also
- * be locked on successful return.
+ * If steal succeeds, buf->page is now pruned from the
+ * pagecache and we can reuse it. The page will also be
+ * locked on successful return.
*/
- if (buf->ops->steal(info, buf))
+ if (buf->ops->steal(pipe, buf))
goto find_page;
page = buf->page;
- page_cache_get(page);
-
- /*
- * page must be on the LRU for adding to the pagecache.
- * Check this without grabbing the zone lock, if it isn't
- * the do grab the zone lock, recheck, and add if necessary.
- */
- if (!PageLRU(page)) {
- struct zone *zone = page_zone(page);
-
- spin_lock_irq(&zone->lru_lock);
- if (!PageLRU(page)) {
- SetPageLRU(page);
- add_page_to_inactive_list(zone, page);
- }
- spin_unlock_irq(&zone->lru_lock);
- }
-
if (add_to_page_cache(page, mapping, index, gfp_mask)) {
- page_cache_release(page);
unlock_page(page);
goto find_page;
}
+
+ page_cache_get(page);
+
+ if (!(buf->flags & PIPE_BUF_FLAG_LRU))
+ lru_cache_add(page);
} else {
find_page:
page = find_lock_page(mapping, index);
@@ -647,23 +638,36 @@ find_page:
}
ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len);
- if (ret == AOP_TRUNCATED_PAGE) {
+ if (unlikely(ret)) {
+ loff_t isize = i_size_read(mapping->host);
+
+ if (ret != AOP_TRUNCATED_PAGE)
+ unlock_page(page);
page_cache_release(page);
- goto find_page;
- } else if (ret)
+ if (ret == AOP_TRUNCATED_PAGE)
+ goto find_page;
+
+ /*
+ * prepare_write() may have instantiated a few blocks
+ * outside i_size. Trim these off again.
+ */
+ if (sd->pos + this_len > isize)
+ vmtruncate(mapping->host, isize);
+
goto out;
+ }
if (buf->page != page) {
/*
* Careful, ->map() uses KM_USER0!
*/
- char *src = buf->ops->map(info, buf, 1);
+ char *src = buf->ops->map(pipe, buf, 1);
char *dst = kmap_atomic(page, KM_USER1);
memcpy(dst + offset, src + buf->offset, this_len);
flush_dcache_page(page);
kunmap_atomic(dst, KM_USER1);
- buf->ops->unmap(info, buf, src);
+ buf->ops->unmap(pipe, buf, src);
}
ret = mapping->a_ops->commit_write(file, page, offset, offset+this_len);