Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 456 insertions, 0 deletions

diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c
new file mode 100644
index 000000000..94d06a76e
--- /dev/null
+++ b/fs/btrfs/zlib.c
@@ -0,0 +1,456 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2008 Oracle.  All rights reserved.
+ *
+ * Based on jffs2 zlib code:
+ * Copyright © 2001-2007 Red Hat, Inc.
+ * Created by David Woodhouse <dwmw2@infradead.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/zlib.h>
+#include <linux/zutil.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/pagemap.h>
+#include <linux/bio.h>
+#include <linux/refcount.h>
+#include "compression.h"
+
+/* workspace buffer size for s390 zlib hardware support */
+#define ZLIB_DFLTCC_BUF_SIZE    (4 * PAGE_SIZE)
+
+struct workspace {
+	z_stream strm;
+	char *buf;
+	unsigned int buf_size;
+	struct list_head list;
+	int level;
+};
+
+static struct workspace_manager wsm;
+
+struct list_head *zlib_get_workspace(unsigned int level)
+{
+	struct list_head *ws = btrfs_get_workspace(BTRFS_COMPRESS_ZLIB, level);
+	struct workspace *workspace = list_entry(ws, struct workspace, list);
+
+	workspace->level = level;
+
+	return ws;
+}
+
+void zlib_free_workspace(struct list_head *ws)
+{
+	struct workspace *workspace = list_entry(ws, struct workspace, list);
+
+	kvfree(workspace->strm.workspace);
+	kfree(workspace->buf);
+	kfree(workspace);
+}
+
+struct list_head *zlib_alloc_workspace(unsigned int level)
+{
+	struct workspace *workspace;
+	int workspacesize;
+
+	workspace = kzalloc(sizeof(*workspace), GFP_KERNEL);
+	if (!workspace)
+		return ERR_PTR(-ENOMEM);
+
+	workspacesize = max(zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL),
+			zlib_inflate_workspacesize());
+	workspace->strm.workspace = kvzalloc(workspacesize, GFP_KERNEL);
+	workspace->level = level;
+	workspace->buf = NULL;
+	/*
+	 * In case of s390 zlib hardware support, allocate lager workspace
+	 * buffer. If allocator fails, fall back to a single page buffer.
+	 */
+	if (zlib_deflate_dfltcc_enabled()) {
+		workspace->buf = kmalloc(ZLIB_DFLTCC_BUF_SIZE,
+					 __GFP_NOMEMALLOC | __GFP_NORETRY |
+					 __GFP_NOWARN | GFP_NOIO);
+		workspace->buf_size = ZLIB_DFLTCC_BUF_SIZE;
+	}
+	if (!workspace->buf) {
+		workspace->buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+		workspace->buf_size = PAGE_SIZE;
+	}
+	if (!workspace->strm.workspace || !workspace->buf)
+		goto fail;
+
+	INIT_LIST_HEAD(&workspace->list);
+
+	return &workspace->list;
+fail:
+	zlib_free_workspace(&workspace->list);
+	return ERR_PTR(-ENOMEM);
+}
+
+int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
+		u64 start, struct page **pages, unsigned long *out_pages,
+		unsigned long *total_in, unsigned long *total_out)
+{
+	struct workspace *workspace = list_entry(ws, struct workspace, list);
+	int ret;
+	char *data_in = NULL;
+	char *cpage_out;
+	int nr_pages = 0;
+	struct page *in_page = NULL;
+	struct page *out_page = NULL;
+	unsigned long bytes_left;
+	unsigned int in_buf_pages;
+	unsigned long len = *total_out;
+	unsigned long nr_dest_pages = *out_pages;
+	const unsigned long max_out = nr_dest_pages * PAGE_SIZE;
+
+	*out_pages = 0;
+	*total_out = 0;
+	*total_in = 0;
+
+	if (Z_OK != zlib_deflateInit(&workspace->strm, workspace->level)) {
+		pr_warn("BTRFS: deflateInit failed\n");
+		ret = -EIO;
+		goto out;
+	}
+
+	workspace->strm.total_in = 0;
+	workspace->strm.total_out = 0;
+
+	out_page = alloc_page(GFP_NOFS);
+	if (out_page == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	cpage_out = page_address(out_page);
+	pages[0] = out_page;
+	nr_pages = 1;
+
+	workspace->strm.next_in = workspace->buf;
+	workspace->strm.avail_in = 0;
+	workspace->strm.next_out = cpage_out;
+	workspace->strm.avail_out = PAGE_SIZE;
+
+	while (workspace->strm.total_in < len) {
+		/*
+		 * Get next input pages and copy the contents to
+		 * the workspace buffer if required.
+		 */
+		if (workspace->strm.avail_in == 0) {
+			bytes_left = len - workspace->strm.total_in;
+			in_buf_pages = min(DIV_ROUND_UP(bytes_left, PAGE_SIZE),
+					   workspace->buf_size / PAGE_SIZE);
+			if (in_buf_pages > 1) {
+				int i;
+
+				for (i = 0; i < in_buf_pages; i++) {
+					if (data_in) {
+						kunmap_local(data_in);
+						put_page(in_page);
+					}
+					in_page = find_get_page(mapping,
+								start >> PAGE_SHIFT);
+					data_in = kmap_local_page(in_page);
+					memcpy(workspace->buf + i * PAGE_SIZE,
+					       data_in, PAGE_SIZE);
+					start += PAGE_SIZE;
+				}
+				workspace->strm.next_in = workspace->buf;
+			} else {
+				if (data_in) {
+					kunmap_local(data_in);
+					put_page(in_page);
+				}
+				in_page = find_get_page(mapping,
+							start >> PAGE_SHIFT);
+				data_in = kmap_local_page(in_page);
+				start += PAGE_SIZE;
+				workspace->strm.next_in = data_in;
+			}
+			workspace->strm.avail_in = min(bytes_left,
+						       (unsigned long) workspace->buf_size);
+		}
+
+		ret = zlib_deflate(&workspace->strm, Z_SYNC_FLUSH);
+		if (ret != Z_OK) {
+			pr_debug("BTRFS: deflate in loop returned %d\n",
+			       ret);
+			zlib_deflateEnd(&workspace->strm);
+			ret = -EIO;
+			goto out;
+		}
+
+		/* we're making it bigger, give up */
+		if (workspace->strm.total_in > 8192 &&
+		    workspace->strm.total_in <
+		    workspace->strm.total_out) {
+			ret = -E2BIG;
+			goto out;
+		}
+		/* we need another page for writing out.  Test this
+		 * before the total_in so we will pull in a new page for
+		 * the stream end if required
+		 */
+		if (workspace->strm.avail_out == 0) {
+			if (nr_pages == nr_dest_pages) {
+				ret = -E2BIG;
+				goto out;
+			}
+			out_page = alloc_page(GFP_NOFS);
+			if (out_page == NULL) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			cpage_out = page_address(out_page);
+			pages[nr_pages] = out_page;
+			nr_pages++;
+			workspace->strm.avail_out = PAGE_SIZE;
+			workspace->strm.next_out = cpage_out;
+		}
+		/* we're all done */
+		if (workspace->strm.total_in >= len)
+			break;
+		if (workspace->strm.total_out > max_out)
+			break;
+	}
+	workspace->strm.avail_in = 0;
+	/*
+	 * Call deflate with Z_FINISH flush parameter providing more output
+	 * space but no more input data, until it returns with Z_STREAM_END.
+	 */
+	while (ret != Z_STREAM_END) {
+		ret = zlib_deflate(&workspace->strm, Z_FINISH);
+		if (ret == Z_STREAM_END)
+			break;
+		if (ret != Z_OK && ret != Z_BUF_ERROR) {
+			zlib_deflateEnd(&workspace->strm);
+			ret = -EIO;
+			goto out;
+		} else if (workspace->strm.avail_out == 0) {
+			/* get another page for the stream end */
+			if (nr_pages == nr_dest_pages) {
+				ret = -E2BIG;
+				goto out;
+			}
+			out_page = alloc_page(GFP_NOFS);
+			if (out_page == NULL) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			cpage_out = page_address(out_page);
+			pages[nr_pages] = out_page;
+			nr_pages++;
+			workspace->strm.avail_out = PAGE_SIZE;
+			workspace->strm.next_out = cpage_out;
+		}
+	}
+	zlib_deflateEnd(&workspace->strm);
+
+	if (workspace->strm.total_out >= workspace->strm.total_in) {
+		ret = -E2BIG;
+		goto out;
+	}
+
+	ret = 0;
+	*total_out = workspace->strm.total_out;
+	*total_in = workspace->strm.total_in;
+out:
+	*out_pages = nr_pages;
+	if (data_in) {
+		kunmap_local(data_in);
+		put_page(in_page);
+	}
+
+	return ret;
+}
+
+int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
+{
+	struct workspace *workspace = list_entry(ws, struct workspace, list);
+	int ret = 0, ret2;
+	int wbits = MAX_WBITS;
+	char *data_in;
+	size_t total_out = 0;
+	unsigned long page_in_index = 0;
+	size_t srclen = cb->compressed_len;
+	unsigned long total_pages_in = DIV_ROUND_UP(srclen, PAGE_SIZE);
+	unsigned long buf_start;
+	struct page **pages_in = cb->compressed_pages;
+
+	data_in = kmap_local_page(pages_in[page_in_index]);
+	workspace->strm.next_in = data_in;
+	workspace->strm.avail_in = min_t(size_t, srclen, PAGE_SIZE);
+	workspace->strm.total_in = 0;
+
+	workspace->strm.total_out = 0;
+	workspace->strm.next_out = workspace->buf;
+	workspace->strm.avail_out = workspace->buf_size;
+
+	/* If it's deflate, and it's got no preset dictionary, then
+	   we can tell zlib to skip the adler32 check. */
+	if (srclen > 2 && !(data_in[1] & PRESET_DICT) &&
+	    ((data_in[0] & 0x0f) == Z_DEFLATED) &&
+	    !(((data_in[0]<<8) + data_in[1]) % 31)) {
+
+		wbits = -((data_in[0] >> 4) + 8);
+		workspace->strm.next_in += 2;
+		workspace->strm.avail_in -= 2;
+	}
+
+	if (Z_OK != zlib_inflateInit2(&workspace->strm, wbits)) {
+		pr_warn("BTRFS: inflateInit failed\n");
+		kunmap_local(data_in);
+		return -EIO;
+	}
+	while (workspace->strm.total_in < srclen) {
+		ret = zlib_inflate(&workspace->strm, Z_NO_FLUSH);
+		if (ret != Z_OK && ret != Z_STREAM_END)
+			break;
+
+		buf_start = total_out;
+		total_out = workspace->strm.total_out;
+
+		/* we didn't make progress in this inflate call, we're done */
+		if (buf_start == total_out)
+			break;
+
+		ret2 = btrfs_decompress_buf2page(workspace->buf,
+				total_out - buf_start, cb, buf_start);
+		if (ret2 == 0) {
+			ret = 0;
+			goto done;
+		}
+
+		workspace->strm.next_out = workspace->buf;
+		workspace->strm.avail_out = workspace->buf_size;
+
+		if (workspace->strm.avail_in == 0) {
+			unsigned long tmp;
+			kunmap_local(data_in);
+			page_in_index++;
+			if (page_in_index >= total_pages_in) {
+				data_in = NULL;
+				break;
+			}
+			data_in = kmap_local_page(pages_in[page_in_index]);
+			workspace->strm.next_in = data_in;
+			tmp = srclen - workspace->strm.total_in;
+			workspace->strm.avail_in = min(tmp, PAGE_SIZE);
+		}
+	}
+	if (ret != Z_STREAM_END)
+		ret = -EIO;
+	else
+		ret = 0;
+done:
+	zlib_inflateEnd(&workspace->strm);
+	if (data_in)
+		kunmap_local(data_in);
+	if (!ret)
+		zero_fill_bio(cb->orig_bio);
+	return ret;
+}
+
+int zlib_decompress(struct list_head *ws, unsigned char *data_in,
+		struct page *dest_page, unsigned long start_byte, size_t srclen,
+		size_t destlen)
+{
+	struct workspace *workspace = list_entry(ws, struct workspace, list);
+	int ret = 0;
+	int wbits = MAX_WBITS;
+	unsigned long bytes_left;
+	unsigned long total_out = 0;
+	unsigned long pg_offset = 0;
+
+	destlen = min_t(unsigned long, destlen, PAGE_SIZE);
+	bytes_left = destlen;
+
+	workspace->strm.next_in = data_in;
+	workspace->strm.avail_in = srclen;
+	workspace->strm.total_in = 0;
+
+	workspace->strm.next_out = workspace->buf;
+	workspace->strm.avail_out = workspace->buf_size;
+	workspace->strm.total_out = 0;
+	/* If it's deflate, and it's got no preset dictionary, then
+	   we can tell zlib to skip the adler32 check. */
+	if (srclen > 2 && !(data_in[1] & PRESET_DICT) &&
+	    ((data_in[0] & 0x0f) == Z_DEFLATED) &&
+	    !(((data_in[0]<<8) + data_in[1]) % 31)) {
+
+		wbits = -((data_in[0] >> 4) + 8);
+		workspace->strm.next_in += 2;
+		workspace->strm.avail_in -= 2;
+	}
+
+	if (Z_OK != zlib_inflateInit2(&workspace->strm, wbits)) {
+		pr_warn("BTRFS: inflateInit failed\n");
+		return -EIO;
+	}
+
+	while (bytes_left > 0) {
+		unsigned long buf_start;
+		unsigned long buf_offset;
+		unsigned long bytes;
+
+		ret = zlib_inflate(&workspace->strm, Z_NO_FLUSH);
+		if (ret != Z_OK && ret != Z_STREAM_END)
+			break;
+
+		buf_start = total_out;
+		total_out = workspace->strm.total_out;
+
+		if (total_out == buf_start) {
+			ret = -EIO;
+			break;
+		}
+
+		if (total_out <= start_byte)
+			goto next;
+
+		if (total_out > start_byte && buf_start < start_byte)
+			buf_offset = start_byte - buf_start;
+		else
+			buf_offset = 0;
+
+		bytes = min(PAGE_SIZE - pg_offset,
+			    PAGE_SIZE - (buf_offset % PAGE_SIZE));
+		bytes = min(bytes, bytes_left);
+
+		memcpy_to_page(dest_page, pg_offset,
+			       workspace->buf + buf_offset, bytes);
+
+		pg_offset += bytes;
+		bytes_left -= bytes;
+next:
+		workspace->strm.next_out = workspace->buf;
+		workspace->strm.avail_out = workspace->buf_size;
+	}
+
+	if (ret != Z_STREAM_END && bytes_left != 0)
+		ret = -EIO;
+	else
+		ret = 0;
+
+	zlib_inflateEnd(&workspace->strm);
+
+	/*
+	 * this should only happen if zlib returned fewer bytes than we
+	 * expected.  btrfs_get_block is responsible for zeroing from the
+	 * end of the inline extent (destlen) to the end of the page
+	 */
+	if (pg_offset < destlen) {
+		memzero_page(dest_page, pg_offset, destlen - pg_offset);
+	}
+	return ret;
+}
+
+const struct btrfs_compress_op btrfs_zlib_compress = {
+	.workspace_manager	= &wsm,
+	.max_level		= 9,
+	.default_level		= BTRFS_ZLIB_DEFAULT_LEVEL,
+};