staging: erofs: switch to new decompression backend

This patch integrates new decompression framework to
erofs decompression path, and remove the old
decompression implementation as well.

On kirin980 platform, sequential read is slightly
improved to 778MiB/s after the new decompression
backend is used.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

5 files changed, 24 insertions, 280 deletions

diff --git a/drivers/staging/erofs/Makefile b/drivers/staging/erofs/Makefile
index adeb5d6e2668..e704d9e51514 100644
--- a/drivers/staging/erofs/Makefile
+++ b/drivers/staging/erofs/Makefile
@@ -9,5 +9,5 @@ obj-$(CONFIG_EROFS_FS) += erofs.o
 ccflags-y += -I $(srctree)/$(src)/include
 erofs-objs := super.o inode.o data.o namei.o dir.o utils.o
 erofs-$(CONFIG_EROFS_FS_XATTR) += xattr.o
-erofs-$(CONFIG_EROFS_FS_ZIP) += unzip_vle.o unzip_vle_lz4.o zmap.o decompressor.o
+erofs-$(CONFIG_EROFS_FS_ZIP) += unzip_vle.o zmap.o decompressor.o
 
diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h
index dcbe6f7f5dae..6c8767d4a1d5 100644
--- a/drivers/staging/erofs/internal.h
+++ b/drivers/staging/erofs/internal.h
@@ -321,15 +321,9 @@ static inline void z_erofs_exit_zip_subsystem(void) {}
 
 /* page count of a compressed cluster */
 #define erofs_clusterpages(sbi)         ((1 << (sbi)->clusterbits) / PAGE_SIZE)
-#define Z_EROFS_NR_INLINE_PAGEVECS      3
 
-#if (Z_EROFS_CLUSTER_MAX_PAGES > Z_EROFS_NR_INLINE_PAGEVECS)
 #define EROFS_PCPUBUF_NR_PAGES          Z_EROFS_CLUSTER_MAX_PAGES
 #else
-#define EROFS_PCPUBUF_NR_PAGES          Z_EROFS_NR_INLINE_PAGEVECS
-#endif
-
-#else
 #define EROFS_PCPUBUF_NR_PAGES          0
 #endif
 
diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c
index d95f985936b6..cb870b83f3c8 100644
--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -897,12 +897,12 @@ static int z_erofs_vle_unzip(struct super_block *sb,
 	unsigned int sparsemem_pages = 0;
 	struct page *pages_onstack[Z_EROFS_VLE_VMAP_ONSTACK_PAGES];
 	struct page **pages, **compressed_pages, *page;
-	unsigned int i, llen;
+	unsigned int algorithm;
+	unsigned int i, outputsize;
 
 	enum z_erofs_page_type page_type;
 	bool overlapped;
 	struct z_erofs_vle_work *work;
-	void *vout;
 	int err;
 
 	might_sleep();
@@ -1009,43 +1009,26 @@ repeat:
 	if (unlikely(err))
 		goto out;
 
-	llen = (nr_pages << PAGE_SHIFT) - work->pageofs;
-
-	if (z_erofs_vle_workgrp_fmt(grp) == Z_EROFS_VLE_WORKGRP_FMT_PLAIN) {
-		err = z_erofs_vle_plain_copy(compressed_pages, clusterpages,
-					     pages, nr_pages, work->pageofs);
-		goto out;
-	}
-
-	if (llen > grp->llen)
-		llen = grp->llen;
-
-	err = z_erofs_vle_unzip_fast_percpu(compressed_pages, clusterpages,
-					    pages, llen, work->pageofs);
-	if (err != -ENOTSUPP)
-		goto out;
-
-	if (sparsemem_pages >= nr_pages)
-		goto skip_allocpage;
-
-	for (i = 0; i < nr_pages; ++i) {
-		if (pages[i])
-			continue;
-
-		pages[i] = __stagingpage_alloc(page_pool, GFP_NOFS);
-	}
-
-skip_allocpage:
-	vout = erofs_vmap(pages, nr_pages);
-	if (!vout) {
-		err = -ENOMEM;
-		goto out;
-	}
-
-	err = z_erofs_vle_unzip_vmap(compressed_pages, clusterpages, vout,
-				     llen, work->pageofs, overlapped);
+	if (nr_pages << PAGE_SHIFT >= work->pageofs + grp->llen)
+		outputsize = grp->llen;
+	else
+		outputsize = (nr_pages << PAGE_SHIFT) - work->pageofs;
 
-	erofs_vunmap(vout, nr_pages);
+	if (z_erofs_vle_workgrp_fmt(grp) == Z_EROFS_VLE_WORKGRP_FMT_PLAIN)
+		algorithm = Z_EROFS_COMPRESSION_SHIFTED;
+	else
+		algorithm = Z_EROFS_COMPRESSION_LZ4;
+
+	err = z_erofs_decompress(&(struct z_erofs_decompress_req) {
+					.sb = sb,
+					.in = compressed_pages,
+					.out = pages,
+					.pageofs_out = work->pageofs,
+					.inputsize = PAGE_SIZE,
+					.outputsize = outputsize,
+					.alg = algorithm,
+					.inplace_io = overlapped,
+					.partial_decoding = true }, page_pool);
 
 out:
 	/* must handle all compressed pages before endding pages */
diff --git a/drivers/staging/erofs/unzip_vle.h b/drivers/staging/erofs/unzip_vle.h
index 6c3e0deb63e7..a2d9b60beebd 100644
--- a/drivers/staging/erofs/unzip_vle.h
+++ b/drivers/staging/erofs/unzip_vle.h
@@ -16,6 +16,8 @@
 #include "internal.h"
 #include "unzip_pagevec.h"
 
+#define Z_EROFS_NR_INLINE_PAGEVECS      3
+
 /*
  * Structure fields follow one of the following exclusion rules.
  *
@@ -189,18 +191,5 @@ static inline void z_erofs_onlinepage_endio(struct page *page)
 	min_t(unsigned int, THREAD_SIZE / 8 / sizeof(struct page *), 96U)
 #define Z_EROFS_VLE_VMAP_GLOBAL_PAGES	2048
 
-/* unzip_vle_lz4.c */
-int z_erofs_vle_plain_copy(struct page **compressed_pages,
-			   unsigned int clusterpages, struct page **pages,
-			   unsigned int nr_pages, unsigned short pageofs);
-int z_erofs_vle_unzip_fast_percpu(struct page **compressed_pages,
-				  unsigned int clusterpages,
-				  struct page **pages, unsigned int outlen,
-				  unsigned short pageofs);
-int z_erofs_vle_unzip_vmap(struct page **compressed_pages,
-			   unsigned int clusterpages,
-			   void *vaddr, unsigned int llen,
-			   unsigned short pageofs, bool overlapped);
-
 #endif
 
diff --git a/drivers/staging/erofs/unzip_vle_lz4.c b/drivers/staging/erofs/unzip_vle_lz4.c
deleted file mode 100644
index 02e694d9288d..000000000000
--- a/drivers/staging/erofs/unzip_vle_lz4.c
+++ /dev/null
@@ -1,222 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * linux/drivers/staging/erofs/unzip_vle_lz4.c
- *
- * Copyright (C) 2018 HUAWEI, Inc.
- *             http://www.huawei.com/
- * Created by Gao Xiang <gaoxiang25@huawei.com>
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file COPYING in the main directory of the Linux
- * distribution for more details.
- */
-#include "unzip_vle.h"
-#include <linux/lz4.h>
-
-static int z_erofs_unzip_lz4(void *in, void *out, size_t inlen, size_t outlen)
-{
-	int ret = LZ4_decompress_safe_partial(in, out, inlen, outlen, outlen);
-
-	if (ret >= 0)
-		return ret;
-
-	/*
-	 * LZ4_decompress_safe_partial will return an error code
-	 * (< 0) if decompression failed
-	 */
-	errln("%s, failed to decompress, in[%p, %zu] outlen[%p, %zu]",
-	      __func__, in, inlen, out, outlen);
-	WARN_ON(1);
-	print_hex_dump(KERN_DEBUG, "raw data [in]: ", DUMP_PREFIX_OFFSET,
-		       16, 1, in, inlen, true);
-	print_hex_dump(KERN_DEBUG, "raw data [out]: ", DUMP_PREFIX_OFFSET,
-		       16, 1, out, outlen, true);
-	return -EIO;
-}
-
-int z_erofs_vle_plain_copy(struct page **compressed_pages,
-			   unsigned int clusterpages,
-			   struct page **pages,
-			   unsigned int nr_pages,
-			   unsigned short pageofs)
-{
-	unsigned int i, j;
-	void *src = NULL;
-	const unsigned int righthalf = PAGE_SIZE - pageofs;
-	char *percpu_data;
-	bool mirrored[Z_EROFS_CLUSTER_MAX_PAGES] = { 0 };
-
-	percpu_data = erofs_get_pcpubuf(0);
-	if (IS_ERR(percpu_data))
-		return PTR_ERR(percpu_data);
-
-	j = 0;
-	for (i = 0; i < nr_pages; j = i++) {
-		struct page *page = pages[i];
-		void *dst;
-
-		if (!page) {
-			if (src) {
-				if (!mirrored[j])
-					kunmap_atomic(src);
-				src = NULL;
-			}
-			continue;
-		}
-
-		dst = kmap_atomic(page);
-
-		for (; j < clusterpages; ++j) {
-			if (compressed_pages[j] != page)
-				continue;
-
-			DBG_BUGON(mirrored[j]);
-			memcpy(percpu_data + j * PAGE_SIZE, dst, PAGE_SIZE);
-			mirrored[j] = true;
-			break;
-		}
-
-		if (i) {
-			if (!src)
-				src = mirrored[i - 1] ?
-					percpu_data + (i - 1) * PAGE_SIZE :
-					kmap_atomic(compressed_pages[i - 1]);
-
-			memcpy(dst, src + righthalf, pageofs);
-
-			if (!mirrored[i - 1])
-				kunmap_atomic(src);
-
-			if (unlikely(i >= clusterpages)) {
-				kunmap_atomic(dst);
-				break;
-			}
-		}
-
-		if (!righthalf) {
-			src = NULL;
-		} else {
-			src = mirrored[i] ? percpu_data + i * PAGE_SIZE :
-				kmap_atomic(compressed_pages[i]);
-
-			memcpy(dst + pageofs, src, righthalf);
-		}
-
-		kunmap_atomic(dst);
-	}
-
-	if (src && !mirrored[j])
-		kunmap_atomic(src);
-
-	erofs_put_pcpubuf(percpu_data);
-	return 0;
-}
-
-int z_erofs_vle_unzip_fast_percpu(struct page **compressed_pages,
-				  unsigned int clusterpages,
-				  struct page **pages,
-				  unsigned int outlen,
-				  unsigned short pageofs)
-{
-	void *vin, *vout;
-	unsigned int nr_pages, i, j;
-	int ret;
-
-	if (outlen + pageofs > EROFS_PCPUBUF_NR_PAGES * PAGE_SIZE)
-		return -ENOTSUPP;
-
-	nr_pages = DIV_ROUND_UP(outlen + pageofs, PAGE_SIZE);
-
-	if (clusterpages == 1) {
-		vin = kmap_atomic(compressed_pages[0]);
-	} else {
-		vin = erofs_vmap(compressed_pages, clusterpages);
-		if (!vin)
-			return -ENOMEM;
-	}
-
-	vout = erofs_get_pcpubuf(0);
-	if (IS_ERR(vout))
-		return PTR_ERR(vout);
-
-	ret = z_erofs_unzip_lz4(vin, vout + pageofs,
-				clusterpages * PAGE_SIZE, outlen);
-
-	if (ret < 0)
-		goto out;
-	ret = 0;
-
-	for (i = 0; i < nr_pages; ++i) {
-		j = min((unsigned int)PAGE_SIZE - pageofs, outlen);
-
-		if (pages[i]) {
-			if (clusterpages == 1 &&
-			    pages[i] == compressed_pages[0]) {
-				memcpy(vin + pageofs, vout + pageofs, j);
-			} else {
-				void *dst = kmap_atomic(pages[i]);
-
-				memcpy(dst + pageofs, vout + pageofs, j);
-				kunmap_atomic(dst);
-			}
-		}
-		vout += PAGE_SIZE;
-		outlen -= j;
-		pageofs = 0;
-	}
-
-out:
-	erofs_put_pcpubuf(vout);
-
-	if (clusterpages == 1)
-		kunmap_atomic(vin);
-	else
-		erofs_vunmap(vin, clusterpages);
-
-	return ret;
-}
-
-int z_erofs_vle_unzip_vmap(struct page **compressed_pages,
-			   unsigned int clusterpages,
-			   void *vout,
-			   unsigned int llen,
-			   unsigned short pageofs,
-			   bool overlapped)
-{
-	void *vin;
-	unsigned int i;
-	int ret;
-
-	if (overlapped) {
-		vin = erofs_get_pcpubuf(0);
-		if (IS_ERR(vin))
-			return PTR_ERR(vin);
-
-		for (i = 0; i < clusterpages; ++i) {
-			void *t = kmap_atomic(compressed_pages[i]);
-
-			memcpy(vin + PAGE_SIZE * i, t, PAGE_SIZE);
-			kunmap_atomic(t);
-		}
-	} else if (clusterpages == 1) {
-		vin = kmap_atomic(compressed_pages[0]);
-	} else {
-		vin = erofs_vmap(compressed_pages, clusterpages);
-	}
-
-	ret = z_erofs_unzip_lz4(vin, vout + pageofs,
-				clusterpages * PAGE_SIZE, llen);
-	if (ret > 0)
-		ret = 0;
-
-	if (overlapped) {
-		erofs_put_pcpubuf(vin);
-	} else {
-		if (clusterpages == 1)
-			kunmap_atomic(vin);
-		else
-			erofs_vunmap(vin, clusterpages);
-	}
-	return ret;
-}
-