[PATCH 10/13] erofs-utils: introduce compression for regular files
Gao Xiang
hsiangkao at aol.com
Fri May 31 10:50:44 AEST 2019
From: Gao Xiang <gaoxiang25 at huawei.com>
Yay! Let's try to transparent file compression
for all regular files if necessary.
Signed-off-by: Gao Xiang <gaoxiang25 at huawei.com>
---
include/erofs/compress.h | 25 ++++
include/erofs/config.h | 2 +
include/erofs/internal.h | 1 +
lib/Makefile.am | 2 +-
lib/compress.c | 303 +++++++++++++++++++++++++++++++++++++++
lib/config.c | 1 +
lib/inode.c | 18 ++-
mkfs/main.c | 21 +++
8 files changed, 369 insertions(+), 4 deletions(-)
create mode 100644 include/erofs/compress.h
create mode 100644 lib/compress.c
diff --git a/include/erofs/compress.h b/include/erofs/compress.h
new file mode 100644
index 0000000..e0abb8f
--- /dev/null
+++ b/include/erofs/compress.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * erofs_utils/include/erofs/compress.h
+ *
+ * Copyright (C) 2019 HUAWEI, Inc.
+ * http://www.huawei.com/
+ * Created by Gao Xiang <gaoxiang25 at huawei.com>
+ */
+#ifndef __EROFS_COMPRESS_H
+#define __EROFS_COMPRESS_H
+
+#include "internal.h"
+
+/* workaround for an upstream lz4 compression issue, which can crash us */
+/* #define EROFS_CONFIG_COMPR_MAX_SZ (1024 * 1024) */
+#define EROFS_CONFIG_COMPR_MAX_SZ (900 * 1024)
+#define EROFS_CONFIG_COMPR_MIN_SZ (32 * 1024)
+
+int erofs_write_compressed_file(struct erofs_inode *inode);
+
+int z_erofs_compress_init(void);
+int z_erofs_compress_exit(void);
+
+#endif
+
diff --git a/include/erofs/config.h b/include/erofs/config.h
index e31732b..177017b 100644
--- a/include/erofs/config.h
+++ b/include/erofs/config.h
@@ -19,6 +19,8 @@ struct erofs_configure {
/* related arguments for mkfs.erofs */
char *c_img_path;
char *c_src_path;
+ char *c_compr_alg_master;
+ int c_compr_level_master;
};
extern struct erofs_configure cfg;
diff --git a/include/erofs/internal.h b/include/erofs/internal.h
index dfa6173..78da589 100644
--- a/include/erofs/internal.h
+++ b/include/erofs/internal.h
@@ -94,6 +94,7 @@ struct erofs_inode {
struct erofs_buffer_head *bh_inline, *bh_data;
void *idata;
+ void *compressmeta;
};
#define IS_ROOT(x) ((x) == (x)->i_parent)
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 17dc9e1..dea82f7 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -2,7 +2,7 @@
# Makefile.am
noinst_LTLIBRARIES = liberofs.la
-liberofs_la_SOURCES = config.c io.c cache.c inode.c compressor.c
+liberofs_la_SOURCES = config.c io.c cache.c inode.c compress.c compressor.c
liberofs_la_CFLAGS = -Wall -Werror -I$(top_srcdir)/include
if ENABLE_LZ4
liberofs_la_CFLAGS += ${LZ4_CFLAGS}
diff --git a/lib/compress.c b/lib/compress.c
new file mode 100644
index 0000000..205a4f2
--- /dev/null
+++ b/lib/compress.c
@@ -0,0 +1,303 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * erofs_utils/lib/compress.c
+ *
+ * Copyright (C) 2018-2019 HUAWEI, Inc.
+ * http://www.huawei.com/
+ * Created by Miao Xie <miaoxie at huawei.com>
+ * with heavy changes by Gao Xiang <gaoxiang25 at huawei.com>
+ */
+#define _LARGEFILE64_SOURCE
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include "erofs/print.h"
+#include "erofs/io.h"
+#include "erofs/cache.h"
+#include "erofs/compress.h"
+#include "compressor.h"
+
+static struct erofs_compress compresshandle;
+static int compressionlevel;
+
+struct z_erofs_vle_compress_ctx {
+ u8 *metacur;
+
+ u8 queue[EROFS_CONFIG_COMPR_MAX_SZ * 2];
+ unsigned int head, tail;
+
+ erofs_blk_t blkaddr; /* pointing to the next blkaddr */
+ u16 clusterofs;
+};
+
+static unsigned int get_vle_compress_metasize(erofs_off_t filesize)
+{
+ const unsigned int indexsize = BLK_ROUND_UP(filesize) *
+ sizeof(struct z_erofs_vle_decompressed_index);
+
+ return sizeof(struct erofs_extent_header) + indexsize;
+}
+
+static void vle_write_indexes_final(struct z_erofs_vle_compress_ctx *ctx)
+{
+ const unsigned int type = Z_EROFS_VLE_CLUSTER_TYPE_PLAIN;
+ struct z_erofs_vle_decompressed_index di;
+
+ if (!ctx->clusterofs)
+ return;
+
+ di.di_clusterofs = cpu_to_le16(ctx->clusterofs);
+ di.di_u.blkaddr = 0;
+ di.di_advise = cpu_to_le16(type << Z_EROFS_VLE_DI_CLUSTER_TYPE_BIT);
+
+ memcpy(ctx->metacur, &di, sizeof(di));
+ ctx->metacur += sizeof(di);
+}
+
+static void vle_write_indexes(struct z_erofs_vle_compress_ctx *ctx,
+ unsigned int count, bool raw)
+{
+ unsigned int d0 = 0, d1 = (ctx->clusterofs + count) / EROFS_BLKSIZ;
+ unsigned int clusterofs = ctx->clusterofs;
+ struct z_erofs_vle_decompressed_index di;
+ unsigned int type;
+ __le16 advise;
+
+ di.di_clusterofs = cpu_to_le16(ctx->clusterofs);
+
+ /* whether the tail-end (un)compressed block or not */
+ if (clusterofs + count < EROFS_BLKSIZ) {
+ type = raw ? Z_EROFS_VLE_CLUSTER_TYPE_PLAIN :
+ Z_EROFS_VLE_CLUSTER_TYPE_HEAD;
+ advise = cpu_to_le16(type << Z_EROFS_VLE_DI_CLUSTER_TYPE_BIT);
+
+ di.di_advise = advise;
+ di.di_u.blkaddr = cpu_to_le32(ctx->blkaddr);
+ memcpy(ctx->metacur, &di, sizeof(di));
+ ctx->metacur += sizeof(di);
+
+ /* don't add the final index if the tail-end block exists */
+ ctx->clusterofs = 0;
+ return;
+ }
+
+ do {
+ if (d0) {
+ type = Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD;
+
+ di.di_u.delta[0] = cpu_to_le16(d0);
+ di.di_u.delta[1] = cpu_to_le16(d1);
+ } else {
+ type = raw ? Z_EROFS_VLE_CLUSTER_TYPE_PLAIN :
+ Z_EROFS_VLE_CLUSTER_TYPE_HEAD;
+ di.di_u.blkaddr = cpu_to_le32(ctx->blkaddr);
+ }
+ advise = cpu_to_le16(type << Z_EROFS_VLE_DI_CLUSTER_TYPE_BIT);
+ di.di_advise = advise;
+
+ memcpy(ctx->metacur, &di, sizeof(di));
+ ctx->metacur += sizeof(di);
+
+ count -= EROFS_BLKSIZ - clusterofs;
+ clusterofs = 0;
+
+ ++d0;
+ --d1;
+ } while (clusterofs + count >= EROFS_BLKSIZ);
+
+ ctx->clusterofs = clusterofs + count;
+}
+
+static int vle_compress_one(struct erofs_inode *inode,
+ struct z_erofs_vle_compress_ctx *ctx,
+ bool final)
+{
+ struct erofs_compress *const h = &compresshandle;
+ unsigned int len = ctx->tail - ctx->head;
+ unsigned int count;
+ int ret;
+ char dst[EROFS_BLKSIZ];
+
+ while (len) {
+ bool raw;
+
+ if (len <= EROFS_BLKSIZ) {
+ if (final)
+ goto nocompression;
+ break;
+ }
+
+ count = len;
+ ret = erofs_compress_destsize(h, compressionlevel,
+ ctx->queue + ctx->head,
+ &count, dst, EROFS_BLKSIZ);
+ if (ret) {
+ if (ret != -EAGAIN) {
+ erofs_err("failed to compress %s: %s",
+ inode->i_srcpath,
+ erofs_strerror(ret));
+ }
+nocompression:
+ /* fix up clusterofs to 0 if possable */
+ if (ctx->head >= ctx->clusterofs) {
+ ctx->head -= ctx->clusterofs;
+ len += ctx->clusterofs;
+ ctx->clusterofs = 0;
+ }
+
+ /* write uncompressed data */
+ count = min(EROFS_BLKSIZ, len);
+
+ memcpy(dst, ctx->queue + ctx->head, count);
+ memset(dst + count, 0, EROFS_BLKSIZ - count);
+
+ erofs_dbg("Writing %u uncompressed data to block %u",
+ count, ctx->blkaddr);
+
+ ret = blk_write(dst, ctx->blkaddr, 1);
+ if (ret)
+ return ret;
+ raw = true;
+ } else {
+ /* write compressed data */
+ erofs_dbg("Writing %u compressed data to block %u",
+ count, ctx->blkaddr);
+
+ ret = blk_write(dst, ctx->blkaddr, 1);
+ if (ret)
+ return ret;
+ raw = false;
+ }
+
+ ctx->head += count;
+ /* write compression indexes for this blkaddr */
+ vle_write_indexes(ctx, count, raw);
+
+ ++ctx->blkaddr;
+ len -= count;
+
+ if (!final && ctx->head >= EROFS_CONFIG_COMPR_MAX_SZ) {
+ const uint qh_aligned = round_down(ctx->head, EROFS_BLKSIZ);
+ const uint qh_after = ctx->head - qh_aligned;
+
+ memmove(ctx->queue, ctx->queue + qh_aligned,
+ len + qh_after);
+ ctx->head = qh_after;
+ ctx->tail = qh_after + len;
+ break;
+ }
+ }
+ return 0;
+}
+
+int erofs_write_compressed_file(struct erofs_inode *inode)
+{
+ const unsigned int metasize = get_vle_compress_metasize(inode->i_size);
+ struct erofs_buffer_head *bh;
+ struct z_erofs_vle_compress_ctx ctx;
+ erofs_off_t remaining;
+ erofs_blk_t blkaddr;
+
+ int ret, fd;
+ u8 *compressmeta = malloc(metasize);
+
+ if (!compressmeta)
+ return -ENOMEM;
+
+ fd = open(inode->i_srcpath, O_RDONLY | O_BINARY);
+ if (fd < 0) {
+ ret = -errno;
+ goto err_free;
+ }
+
+ /* allocate main data buffer */
+ bh = erofs_balloc(DATA, 0, 0, 0);
+ if (IS_ERR(bh)) {
+ ret = PTR_ERR(bh);
+ goto err_close;
+ }
+
+ blkaddr = erofs_mapbh(bh->block, true); /* start_blkaddr */
+ ctx.blkaddr = blkaddr;
+ ctx.metacur = compressmeta + sizeof(struct erofs_extent_header);
+ ctx.head = ctx.tail = 0;
+ ctx.clusterofs = 0;
+ remaining = inode->i_size;
+
+ while (remaining) {
+ const uint readcount = min_t(uint, remaining,
+ sizeof(ctx.queue) - ctx.tail);
+
+ ret = read(fd, ctx.queue + ctx.tail, readcount);
+ if (ret != readcount) {
+ ret = -errno;
+ goto err_bdrop;
+ }
+ remaining -= readcount;
+ ctx.tail += readcount;
+
+ /* do one compress round */
+ ret = vle_compress_one(inode, &ctx, false);
+ if (ret)
+ goto err_bdrop;
+ }
+
+ /* do the final round */
+ ret = vle_compress_one(inode, &ctx, true);
+ if (ret)
+ goto err_bdrop;
+
+ /* fall back to no compression mode */
+ if (ctx.blkaddr - blkaddr >= BLK_ROUND_UP(inode->i_size)) {
+ ret = -ENOSPC;
+ goto err_bdrop;
+ }
+
+ vle_write_indexes_final(&ctx);
+
+ close(fd);
+ ret = erofs_bh_balloon(bh, blknr_to_addr(ctx.blkaddr - blkaddr));
+ DBG_BUGON(ret);
+
+ erofs_info("compressed %s (%lu bytes) into %u blocks",
+ inode->i_srcpath, inode->i_size, ctx.blkaddr - blkaddr);
+
+ /*
+ * TODO: need to move erofs_bdrop to erofs_write_tail_end
+ * when both mkfs & kernel support compression inline.
+ */
+ erofs_bdrop(bh, false);
+ inode->compressmeta = compressmeta;
+ inode->idata_size = 0;
+ inode->extent_isize = metasize;
+ inode->data_mapping_mode = EROFS_INODE_LAYOUT_COMPRESSION;
+ return 0;
+
+err_bdrop:
+ erofs_bdrop(bh, true); /* revoke buffer */
+err_close:
+ close(fd);
+err_free:
+ free(compressmeta);
+ return ret;
+}
+
+int z_erofs_compress_init(void)
+{
+ /* initialize for primary compression algorithm */
+ int ret = erofs_compressor_init(&compresshandle,
+ cfg.c_compr_alg_master);
+ if (ret)
+ return ret;
+
+ compressionlevel = cfg.c_compr_level_master < 0 ?
+ compresshandle.alg->default_level :
+ cfg.c_compr_level_master;
+ return 0;
+}
+
+int z_erofs_compress_exit(void)
+{
+ return erofs_compressor_exit(&compresshandle);
+}
+
diff --git a/lib/config.c b/lib/config.c
index 6ff8e4d..3312c9b 100644
--- a/lib/config.c
+++ b/lib/config.c
@@ -18,6 +18,7 @@ void erofs_init_configure(void)
cfg.c_dbg_lvl = 0;
cfg.c_version = PACKAGE_VERSION;
cfg.c_dry_run = false;
+ cfg.c_compr_level_master = -1;
}
void erofs_show_config(void)
diff --git a/lib/inode.c b/lib/inode.c
index d3e5ed8..b7fcf0e 100644
--- a/lib/inode.c
+++ b/lib/inode.c
@@ -17,6 +17,7 @@
#include "erofs/inode.h"
#include "erofs/cache.h"
#include "erofs/io.h"
+#include "erofs/compress.h"
struct erofs_sb_info sbi;
@@ -286,8 +287,11 @@ int erofs_write_file(struct erofs_inode *inode)
unsigned int nblocks, i;
int ret, fd;
- if (erofs_file_is_compressible(inode)) {
- /* to be implemented */
+ if (cfg.c_compr_alg_master && erofs_file_is_compressible(inode)) {
+ ret = erofs_write_compressed_file(inode);
+
+ if (!ret || ret != -ENOSPC)
+ return ret;
}
/* fallback to all data uncompressed */
@@ -340,7 +344,7 @@ fail:
static bool erofs_bh_flush_write_inode(struct erofs_buffer_head *bh)
{
struct erofs_inode *const inode = bh->fsprivate;
- const erofs_off_t off = erofs_btell(bh, false);
+ erofs_off_t off = erofs_btell(bh, false);
/* let's support v1 currently */
struct erofs_inode_v1 v1 = {0};
@@ -379,6 +383,14 @@ static bool erofs_bh_flush_write_inode(struct erofs_buffer_head *bh)
if (ret)
return false;
+ if (inode->extent_isize) {
+ /* write compression metadata */
+ off = Z_EROFS_VLE_EXTENT_ALIGN(off + inode->inode_isize);
+ ret = dev_write(inode->compressmeta, off, inode->extent_isize);
+ if (ret)
+ return false;
+ }
+
erofs_iput(inode);
return erofs_bh_flush_generic_end(bh);
}
diff --git a/mkfs/main.c b/mkfs/main.c
index 1ed15d2..ce64ece 100644
--- a/mkfs/main.c
+++ b/mkfs/main.c
@@ -17,6 +17,7 @@
#include "erofs/cache.h"
#include "erofs/inode.h"
#include "erofs/io.h"
+#include "erofs/compress.h"
#define EROFS_SUPER_END (EROFS_SUPER_OFFSET + sizeof(struct erofs_super_block))
@@ -25,6 +26,7 @@ static void usage(char *execpath)
fprintf(stderr, "%s %s\n", basename(execpath), cfg.c_version);
fprintf(stderr, "usage: [options] FILE DIRECTORY\n\n");
fprintf(stderr, "Generate erofs image from DIRECTORY to FILE, and [options] are:\n");
+ fprintf(stderr, " -zX[,Y] X=compressor (Y=compression level, optional)\n");
fprintf(stderr, " -d# set output message level to # (maximum 9)\n");
}
@@ -44,6 +46,23 @@ static int mkfs_parse_options_cfg(int argc, char *argv[])
while ((opt = getopt(argc, argv, "d:z:")) != -1) {
switch (opt) {
+ case 'z':
+ if (!optarg) {
+ cfg.c_compr_alg_master = "(default)";
+ break;
+ }
+ /* get specified compression level */
+ for (i = 0; optarg[i] != '\0'; ++i) {
+ if (optarg[i] == ',') {
+ cfg.c_compr_level_master =
+ atoi(optarg + i + 1);
+ optarg[i] = '\0';
+ break;
+ }
+ }
+ cfg.c_compr_alg_master = strndup(optarg, i);
+ break;
+
case 'd':
cfg.c_dbg_lvl = parse_num_from_str(optarg);
break;
@@ -148,6 +167,7 @@ int main(int argc, char **argv)
goto exit;
}
+ z_erofs_compress_init();
erofs_inode_manager_init();
root_inode = erofs_mkfs_build_tree_from_path(NULL, cfg.c_src_path);
@@ -167,6 +187,7 @@ int main(int argc, char **argv)
if (!erofs_bflush(NULL))
err = -EIO;
exit:
+ z_erofs_compress_exit();
dev_close();
erofs_exit_configure();
--
2.17.1
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