[PATCH] erofs-utils: clevel set up as an individual function

[Gao Xiang]

Compression level passed in can be verified then. Also, in order for
preparation of upcoming LZMA fixed-sized output compression.

Signed-off-by: Gao Xiang <xiang at kernel.org>
---
A preparing patch for LZMA and range LZ4 dictionary I'd like to merge
in advance.

 lib/compress.c         | 11 ++++-------
 lib/compressor.c       | 22 +++++++++++++++-------
 lib/compressor.h       |  6 ++++--
 lib/compressor_lz4.c   |  1 -
 lib/compressor_lz4hc.c | 21 +++++++++++++++------
 5 files changed, 38 insertions(+), 23 deletions(-)

diff --git a/lib/compress.c b/lib/compress.c
index 36c6a28ad0f6..6ca5bedaf596 100644
--- a/lib/compress.c
+++ b/lib/compress.c
@@ -20,8 +20,6 @@
 #include "erofs/compress_hints.h"
 
 static struct erofs_compress compresshandle;
-static int compressionlevel;
-
 static unsigned int algorithmtype[2];
 
 struct z_erofs_vle_compress_ctx {
@@ -190,8 +188,7 @@ static int vle_compress_one(struct erofs_inode *inode,
 		}
 
 		count = min(len, cfg.c_max_decompressed_extent_bytes);
-		ret = erofs_compress_destsize(h, compressionlevel,
-					      ctx->queue + ctx->head,
+		ret = erofs_compress_destsize(h, ctx->queue + ctx->head,
 					      &count, dst, pclustersize);
 		if (ret <= 0) {
 			if (ret != -EAGAIN) {
@@ -645,9 +642,9 @@ int z_erofs_compress_init(struct erofs_buffer_head *sb_bh)
 	if (!cfg.c_compr_alg_master)
 		return 0;
 
-	compressionlevel = cfg.c_compr_level_master < 0 ?
-		compresshandle.alg->default_level :
-		cfg.c_compr_level_master;
+	ret = erofs_compressor_setlevel(&compresshandle, cfg.c_compr_level_master);
+	if (ret)
+		return ret;
 
 	/* figure out primary algorithm */
 	ret = erofs_get_compress_algorithm_id(cfg.c_compr_alg_master);
diff --git a/lib/compressor.c b/lib/compressor.c
index 1f1a33d099ba..89c1be10dd0c 100644
--- a/lib/compressor.c
+++ b/lib/compressor.c
@@ -20,11 +20,8 @@ static struct erofs_compressor *compressors[] = {
 };
 
 int erofs_compress_destsize(struct erofs_compress *c,
-			    int compression_level,
-			    void *src,
-			    unsigned int *srcsize,
-			    void *dst,
-			    unsigned int dstsize)
+			    void *src, unsigned int *srcsize,
+			    void *dst, unsigned int dstsize)
 {
 	unsigned int uncompressed_size;
 	int ret;
@@ -33,8 +30,7 @@ int erofs_compress_destsize(struct erofs_compress *c,
 	if (!c->alg->compress_destsize)
 		return -ENOTSUP;
 
-	ret = c->alg->compress_destsize(c, compression_level,
-					src, srcsize, dst, dstsize);
+	ret = c->alg->compress_destsize(c, src, srcsize, dst, dstsize);
 	if (ret < 0)
 		return ret;
 
@@ -51,6 +47,18 @@ const char *z_erofs_list_available_compressors(unsigned int i)
 	return i >= ARRAY_SIZE(compressors) ? NULL : compressors[i]->name;
 }
 
+int erofs_compressor_setlevel(struct erofs_compress *c, int compression_level)
+{
+	DBG_BUGON(!c->alg);
+	if (c->alg->setlevel)
+		return c->alg->setlevel(c, compression_level);
+
+	if (compression_level >= 0)
+		return -EINVAL;
+	c->compression_level = 0;
+	return 0;
+}
+
 int erofs_compressor_init(struct erofs_compress *c, char *alg_name)
 {
 	int ret, i;
diff --git a/lib/compressor.h b/lib/compressor.h
index 151c43d607db..d1b43c87291f 100644
--- a/lib/compressor.h
+++ b/lib/compressor.h
@@ -19,9 +19,9 @@ struct erofs_compressor {
 
 	int (*init)(struct erofs_compress *c);
 	int (*exit)(struct erofs_compress *c);
+	int (*setlevel)(struct erofs_compress *c, int compression_level);
 
 	int (*compress_destsize)(struct erofs_compress *c,
-				 int compress_level,
 				 void *src, unsigned int *srcsize,
 				 void *dst, unsigned int dstsize);
 };
@@ -30,6 +30,7 @@ struct erofs_compress {
 	struct erofs_compressor *alg;
 
 	unsigned int compress_threshold;
+	unsigned int compression_level;
 
 	/* *_destsize specific */
 	unsigned int destsize_alignsize;
@@ -43,10 +44,11 @@ struct erofs_compress {
 extern struct erofs_compressor erofs_compressor_lz4;
 extern struct erofs_compressor erofs_compressor_lz4hc;
 
-int erofs_compress_destsize(struct erofs_compress *c, int compression_level,
+int erofs_compress_destsize(struct erofs_compress *c,
 			    void *src, unsigned int *srcsize,
 			    void *dst, unsigned int dstsize);
 
+int erofs_compressor_setlevel(struct erofs_compress *c, int compression_level);
 int erofs_compressor_init(struct erofs_compress *c, char *alg_name);
 int erofs_compressor_exit(struct erofs_compress *c);
 
diff --git a/lib/compressor_lz4.c b/lib/compressor_lz4.c
index f71252ed6dca..f6832be251b2 100644
--- a/lib/compressor_lz4.c
+++ b/lib/compressor_lz4.c
@@ -13,7 +13,6 @@
 #endif
 
 static int lz4_compress_destsize(struct erofs_compress *c,
-				 int compression_level,
 				 void *src, unsigned int *srcsize,
 				 void *dst, unsigned int dstsize)
 {
diff --git a/lib/compressor_lz4hc.c b/lib/compressor_lz4hc.c
index 0c912fb0ea1e..fd801ab16f37 100644
--- a/lib/compressor_lz4hc.c
+++ b/lib/compressor_lz4hc.c
@@ -14,16 +14,13 @@
 #endif
 
 static int lz4hc_compress_destsize(struct erofs_compress *c,
-				   int compression_level,
-				   void *src,
-				   unsigned int *srcsize,
-				   void *dst,
-				   unsigned int dstsize)
+				   void *src, unsigned int *srcsize,
+				   void *dst, unsigned int dstsize)
 {
 	int srcSize = (int)*srcsize;
 	int rc = LZ4_compress_HC_destSize(c->private_data, src, dst,
 					  &srcSize, (int)dstsize,
-					  compression_level);
+					  c->compression_level);
 	if (!rc)
 		return -EFAULT;
 	*srcsize = srcSize;
@@ -51,11 +48,23 @@ static int compressor_lz4hc_init(struct erofs_compress *c)
 	return 0;
 }
 
+static int compressor_lz4hc_setlevel(struct erofs_compress *c,
+				     int compression_level)
+{
+	if (compression_level > LZ4HC_CLEVEL_MAX)
+		return -EINVAL;
+
+	c->compression_level = compression_level < 0 ?
+		LZ4HC_CLEVEL_DEFAULT : compression_level;
+	return 0;
+}
+
 struct erofs_compressor erofs_compressor_lz4hc = {
 	.name = "lz4hc",
 	.default_level = LZ4HC_CLEVEL_DEFAULT,
 	.best_level = LZ4HC_CLEVEL_MAX,
 	.init = compressor_lz4hc_init,
 	.exit = compressor_lz4hc_exit,
+	.setlevel = compressor_lz4hc_setlevel,
 	.compress_destsize = lz4hc_compress_destsize,
 };
-- 
2.20.1