[PATCH] splice: fix offset problems (016b661e) · Commits · 戴 / test

fs/splice.c

+27 −19

Original line number	Diff line number	Diff line
		@@ -439,14 +439,13 @@ EXPORT_SYMBOL(generic_file_splice_read);

		/*
		* Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos'
		* using sendpage().
		* using sendpage(). Return the number of bytes sent.
		*/
		static int pipe_to_sendpage(struct pipe_inode_info *info,
		struct pipe_buffer buf, struct splice_desc sd)
		{
		struct file *file = sd->file;
		loff_t pos = sd->pos;
		unsigned int offset;
		ssize_t ret;
		void *ptr;
		int more;
		@@ -461,16 +460,13 @@ static int pipe_to_sendpage(struct pipe_inode_info *info,
		if (IS_ERR(ptr))
		return PTR_ERR(ptr);

		offset = pos & ~PAGE_CACHE_MASK;
		more = (sd->flags & SPLICE_F_MORE) \|\| sd->len < sd->total_len;

		ret = file->f_op->sendpage(file, buf->page, offset, sd->len, &pos,more);
		ret = file->f_op->sendpage(file, buf->page, buf->offset, sd->len,
		&pos, more);

		buf->ops->unmap(info, buf);
		if (ret == sd->len)
		return 0;

		return -EIO;
		return ret;
		}

		/*
		@@ -499,7 +495,7 @@ static int pipe_to_file(struct pipe_inode_info info, struct pipe_buffer buf,
		struct file *file = sd->file;
		struct address_space *mapping = file->f_mapping;
		gfp_t gfp_mask = mapping_gfp_mask(mapping);
		unsigned int offset;
		unsigned int offset, this_len;
		struct page *page;
		pgoff_t index;
		char *src;
		@@ -515,6 +511,10 @@ static int pipe_to_file(struct pipe_inode_info info, struct pipe_buffer buf,
		index = sd->pos >> PAGE_CACHE_SHIFT;
		offset = sd->pos & ~PAGE_CACHE_MASK;

		this_len = sd->len;
		if (this_len + offset > PAGE_CACHE_SIZE)
		this_len = PAGE_CACHE_SIZE - offset;

		/*
		* Reuse buf page, if SPLICE_F_MOVE is set.
		*/
		@@ -558,7 +558,7 @@ find_page:
		* the full page.
		*/
		if (!PageUptodate(page)) {
		if (sd->len < PAGE_CACHE_SIZE) {
		if (this_len < PAGE_CACHE_SIZE) {
		ret = mapping->a_ops->readpage(file, page);
		if (unlikely(ret))
		goto out;
		@@ -582,7 +582,7 @@ find_page:
		}
		}

		ret = mapping->a_ops->prepare_write(file, page, 0, sd->len);
		ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len);
		if (ret == AOP_TRUNCATED_PAGE) {
		page_cache_release(page);
		goto find_page;
		@@ -592,18 +592,22 @@ find_page:
		if (!(buf->flags & PIPE_BUF_FLAG_STOLEN)) {
		char *dst = kmap_atomic(page, KM_USER0);

		memcpy(dst + offset, src + buf->offset, sd->len);
		memcpy(dst + offset, src + buf->offset, this_len);
		flush_dcache_page(page);
		kunmap_atomic(dst, KM_USER0);
		}

		ret = mapping->a_ops->commit_write(file, page, 0, sd->len);
		ret = mapping->a_ops->commit_write(file, page, offset, offset+this_len);
		if (ret == AOP_TRUNCATED_PAGE) {
		page_cache_release(page);
		goto find_page;
		} else if (ret)
		goto out;

		/*
		* Return the number of bytes written.
		*/
		ret = this_len;
		mark_page_accessed(page);
		balance_dirty_pages_ratelimited(mapping);
		out:
		@@ -652,16 +656,22 @@ static ssize_t move_from_pipe(struct pipe_inode_info pipe, struct file out,
		sd.len = sd.total_len;

		err = actor(pipe, buf, &sd);
		if (err) {
		if (err <= 0) {
		if (!ret && err != -ENODATA)
		ret = err;

		break;
		}

		ret += sd.len;
		buf->offset += sd.len;
		buf->len -= sd.len;
		ret += err;
		buf->offset += err;
		buf->len -= err;

		sd.len -= err;
		sd.pos += err;
		sd.total_len -= err;
		if (sd.len)
		continue;

		if (!buf->len) {
		buf->ops = NULL;
		@@ -672,8 +682,6 @@ static ssize_t move_from_pipe(struct pipe_inode_info pipe, struct file out,
		do_wakeup = 1;
		}

		sd.pos += sd.len;
		sd.total_len -= sd.len;
		if (!sd.total_len)
		break;
		}

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