Commit 8c945d32 authored by David Sterba's avatar David Sterba
Browse files

btrfs: compression: drop kmap/kunmap from lzo 



As we don't use highmem pages anymore, drop the kmap/kunmap. The kmap is
simply page_address and kunmap is a no-op.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent b0ee5e1e

fs/btrfs/lzo.c

+10 −28
Original line number Diff line number Diff line
@@ -140,7 +140,7 @@ int lzo_compress_pages(struct list_head *ws, struct address_space *mapping, 
	*total_in = 0;



	in_page = find_get_page(mapping, start >> PAGE_SHIFT);

	data_in = kmap(in_page);

	data_in = page_address(in_page);



	/*

	 * store the size of all chunks of compressed data in
@@ -151,7 +151,7 @@ int lzo_compress_pages(struct list_head *ws, struct address_space *mapping, 
		ret = -ENOMEM;

		goto out;

	}

	cpage_out = kmap(out_page);

	cpage_out = page_address(out_page);

	out_offset = LZO_LEN;

	tot_out = LZO_LEN;

	pages[0] = out_page;
@@ -209,7 +209,6 @@ int lzo_compress_pages(struct list_head *ws, struct address_space *mapping, 
				if (out_len == 0 && tot_in >= len)

					break;



				kunmap(out_page);

				if (nr_pages == nr_dest_pages) {

					out_page = NULL;

					ret = -E2BIG;
@@ -221,7 +220,7 @@ int lzo_compress_pages(struct list_head *ws, struct address_space *mapping, 
					ret = -ENOMEM;

					goto out;

				}

				cpage_out = kmap(out_page);

				cpage_out = page_address(out_page);

				pages[nr_pages++] = out_page;



				pg_bytes_left = PAGE_SIZE;
@@ -243,12 +242,11 @@ int lzo_compress_pages(struct list_head *ws, struct address_space *mapping, 
			break;



		bytes_left = len - tot_in;

		kunmap(in_page);

		put_page(in_page);



		start += PAGE_SIZE;

		in_page = find_get_page(mapping, start >> PAGE_SHIFT);

		data_in = kmap(in_page);

		data_in = page_address(in_page);

		in_len = min(bytes_left, PAGE_SIZE);

	}
@@ -258,22 +256,17 @@ int lzo_compress_pages(struct list_head *ws, struct address_space *mapping, 
	}



	/* store the size of all chunks of compressed data */

	sizes_ptr = kmap_local_page(pages[0]);

	sizes_ptr = page_address(pages[0]);

	write_compress_length(sizes_ptr, tot_out);

	kunmap_local(sizes_ptr);



	ret = 0;

	*total_out = tot_out;

	*total_in = tot_in;

out:

	*out_pages = nr_pages;

	if (out_page)

		kunmap(out_page);



	if (in_page) {

		kunmap(in_page);

	if (in_page)

		put_page(in_page);

	}



	return ret;

}
@@ -299,12 +292,11 @@ int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb) 
	unsigned long tot_out;

	unsigned long tot_len;

	char *buf;

	bool may_late_unmap, need_unmap;

	struct page **pages_in = cb->compressed_pages;

	u64 disk_start = cb->start;

	struct bio *orig_bio = cb->orig_bio;



	data_in = kmap(pages_in[0]);

	data_in = page_address(pages_in[0]);

	tot_len = read_compress_length(data_in);

	/*

	 * Compressed data header check.
@@ -345,13 +337,11 @@ int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb) 


		tot_in += in_len;

		working_bytes = in_len;

		may_late_unmap = need_unmap = false;



		/* fast path: avoid using the working buffer */

		if (in_page_bytes_left >= in_len) {

			buf = data_in + in_offset;

			bytes = in_len;

			may_late_unmap = true;

			goto cont;

		}
@@ -381,12 +371,8 @@ int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb) 
					goto done;

				}



				if (may_late_unmap)

					need_unmap = true;

				else

					kunmap(pages_in[page_in_index]);



				data_in = kmap(pages_in[++page_in_index]);

				page_in_index++;

				data_in = page_address(pages_in[page_in_index]);



				in_page_bytes_left = PAGE_SIZE;

				in_offset = 0;
@@ -396,8 +382,6 @@ int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb) 
		out_len = max_segment_len;

		ret = lzo1x_decompress_safe(buf, in_len, workspace->buf,

					    &out_len);

		if (need_unmap)

			kunmap(pages_in[page_in_index - 1]);

		if (ret != LZO_E_OK) {

			pr_warn("BTRFS: decompress failed\n");

			ret = -EIO;
@@ -413,7 +397,6 @@ int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb) 
			break;

	}

done:

	kunmap(pages_in[page_in_index]);

	if (!ret)

		zero_fill_bio(orig_bio);

	return ret;
@@ -466,7 +449,7 @@ int lzo_decompress(struct list_head *ws, unsigned char *data_in, 
	destlen = min_t(unsigned long, destlen, PAGE_SIZE);

	bytes = min_t(unsigned long, destlen, out_len - start_byte);



	kaddr = kmap_local_page(dest_page);

	kaddr = page_address(dest_page);

	memcpy(kaddr, workspace->buf + start_byte, bytes);



	/*
@@ -476,7 +459,6 @@ int lzo_decompress(struct list_head *ws, unsigned char *data_in, 
	 */

	if (bytes < destlen)

		memset(kaddr+bytes, 0, destlen-bytes);

	kunmap_local(kaddr);

out:

	return ret;

}