[PATCH v3 7/8] staging: erofs: switch to new decompression backend

From: Gao Xiang
Date: Mon Jun 24 2019 - 03:24:08 EST


From: Gao Xiang <gaoxiang25@xxxxxxxxxx>

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@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
---
drivers/staging/erofs/Makefile | 2 +-
drivers/staging/erofs/internal.h | 6 -
drivers/staging/erofs/unzip_vle.c | 59 +++----
drivers/staging/erofs/unzip_vle.h | 15 +-
drivers/staging/erofs/unzip_vle_lz4.c | 222 --------------------------
5 files changed, 24 insertions(+), 280 deletions(-)
delete mode 100644 drivers/staging/erofs/unzip_vle_lz4.c

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
@@ -321,14 +321,8 @@ 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 @@ static int z_erofs_vle_unzip(struct super_block *sb,
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@xxxxxxxxxx>
- *
- * 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;
-}
-
--
2.17.1