lib: zstd: Add kernel-specific API

This patch:
- Moves `include/linux/zstd.h` -> `include/linux/zstd_lib.h`
- Updates modified zstd headers to yearless copyright
- Adds a new API in `include/linux/zstd.h` that is functionally
  equivalent to the in-use subset of the current API. Functions are
  renamed to avoid symbol collisions with zstd, to make it clear it is
  not the upstream zstd API, and to follow the kernel style guide.
- Updates all callers to use the new API.

There are no functional changes in this patch. Since there are no
functional change, I felt it was okay to update all the callers in a
single patch. Once the API is approved, the callers are mechanically
changed.

This patch is preparing for the 3rd patch in this series, which updates
zstd to version 1.4.10. Since the upstream zstd API is no longer exposed
to callers, the update can happen transparently.

Signed-off-by: Nick Terrell <terrelln@fb.com>
Tested By: Paul Jones <paul@pauljones.id.au>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 on x86-64
Tested-by: Jean-Denis Girard <jd.girard@sysnux.pf>

2 files changed, 29 insertions, 29 deletions

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index 20a083dc9042..b8d70deddfb7 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -336,8 +336,8 @@ static const struct f2fs_compress_ops f2fs_lz4_ops = {
 
 static int zstd_init_compress_ctx(struct compress_ctx *cc)
 {
-	ZSTD_parameters params;
-	ZSTD_CStream *stream;
+	zstd_parameters params;
+	zstd_cstream *stream;
 	void *workspace;
 	unsigned int workspace_size;
 	unsigned char level = F2FS_I(cc->inode)->i_compress_flag >>
@@ -346,17 +346,17 @@ static int zstd_init_compress_ctx(struct compress_ctx *cc)
 	if (!level)
 		level = F2FS_ZSTD_DEFAULT_CLEVEL;
 
-	params = ZSTD_getParams(level, cc->rlen, 0);
-	workspace_size = ZSTD_CStreamWorkspaceBound(params.cParams);
+	params = zstd_get_params(F2FS_ZSTD_DEFAULT_CLEVEL, cc->rlen);
+	workspace_size = zstd_cstream_workspace_bound(&params.cParams);
 
 	workspace = f2fs_kvmalloc(F2FS_I_SB(cc->inode),
 					workspace_size, GFP_NOFS);
 	if (!workspace)
 		return -ENOMEM;
 
-	stream = ZSTD_initCStream(params, 0, workspace, workspace_size);
+	stream = zstd_init_cstream(&params, 0, workspace, workspace_size);
 	if (!stream) {
-		printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_initCStream failed\n",
+		printk_ratelimited("%sF2FS-fs (%s): %s zstd_init_cstream failed\n",
 				KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
 				__func__);
 		kvfree(workspace);
@@ -379,9 +379,9 @@ static void zstd_destroy_compress_ctx(struct compress_ctx *cc)
 
 static int zstd_compress_pages(struct compress_ctx *cc)
 {
-	ZSTD_CStream *stream = cc->private2;
-	ZSTD_inBuffer inbuf;
-	ZSTD_outBuffer outbuf;
+	zstd_cstream *stream = cc->private2;
+	zstd_in_buffer inbuf;
+	zstd_out_buffer outbuf;
 	int src_size = cc->rlen;
 	int dst_size = src_size - PAGE_SIZE - COMPRESS_HEADER_SIZE;
 	int ret;
@@ -394,19 +394,19 @@ static int zstd_compress_pages(struct compress_ctx *cc)
 	outbuf.dst = cc->cbuf->cdata;
 	outbuf.size = dst_size;
 
-	ret = ZSTD_compressStream(stream, &outbuf, &inbuf);
-	if (ZSTD_isError(ret)) {
-		printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_compressStream failed, ret: %d\n",
+	ret = zstd_compress_stream(stream, &outbuf, &inbuf);
+	if (zstd_is_error(ret)) {
+		printk_ratelimited("%sF2FS-fs (%s): %s zstd_compress_stream failed, ret: %d\n",
 				KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
-				__func__, ZSTD_getErrorCode(ret));
+				__func__, zstd_get_error_code(ret));
 		return -EIO;
 	}
 
-	ret = ZSTD_endStream(stream, &outbuf);
-	if (ZSTD_isError(ret)) {
-		printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_endStream returned %d\n",
+	ret = zstd_end_stream(stream, &outbuf);
+	if (zstd_is_error(ret)) {
+		printk_ratelimited("%sF2FS-fs (%s): %s zstd_end_stream returned %d\n",
 				KERN_ERR, F2FS_I_SB(cc->inode)->sb->s_id,
-				__func__, ZSTD_getErrorCode(ret));
+				__func__, zstd_get_error_code(ret));
 		return -EIO;
 	}
 
@@ -423,22 +423,22 @@ static int zstd_compress_pages(struct compress_ctx *cc)
 
 static int zstd_init_decompress_ctx(struct decompress_io_ctx *dic)
 {
-	ZSTD_DStream *stream;
+	zstd_dstream *stream;
 	void *workspace;
 	unsigned int workspace_size;
 	unsigned int max_window_size =
 			MAX_COMPRESS_WINDOW_SIZE(dic->log_cluster_size);
 
-	workspace_size = ZSTD_DStreamWorkspaceBound(max_window_size);
+	workspace_size = zstd_dstream_workspace_bound(max_window_size);
 
 	workspace = f2fs_kvmalloc(F2FS_I_SB(dic->inode),
 					workspace_size, GFP_NOFS);
 	if (!workspace)
 		return -ENOMEM;
 
-	stream = ZSTD_initDStream(max_window_size, workspace, workspace_size);
+	stream = zstd_init_dstream(max_window_size, workspace, workspace_size);
 	if (!stream) {
-		printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_initDStream failed\n",
+		printk_ratelimited("%sF2FS-fs (%s): %s zstd_init_dstream failed\n",
 				KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id,
 				__func__);
 		kvfree(workspace);
@@ -460,9 +460,9 @@ static void zstd_destroy_decompress_ctx(struct decompress_io_ctx *dic)
 
 static int zstd_decompress_pages(struct decompress_io_ctx *dic)
 {
-	ZSTD_DStream *stream = dic->private2;
-	ZSTD_inBuffer inbuf;
-	ZSTD_outBuffer outbuf;
+	zstd_dstream *stream = dic->private2;
+	zstd_in_buffer inbuf;
+	zstd_out_buffer outbuf;
 	int ret;
 
 	inbuf.pos = 0;
@@ -473,11 +473,11 @@ static int zstd_decompress_pages(struct decompress_io_ctx *dic)
 	outbuf.dst = dic->rbuf;
 	outbuf.size = dic->rlen;
 
-	ret = ZSTD_decompressStream(stream, &outbuf, &inbuf);
-	if (ZSTD_isError(ret)) {
-		printk_ratelimited("%sF2FS-fs (%s): %s ZSTD_compressStream failed, ret: %d\n",
+	ret = zstd_decompress_stream(stream, &outbuf, &inbuf);
+	if (zstd_is_error(ret)) {
+		printk_ratelimited("%sF2FS-fs (%s): %s zstd_decompress_stream failed, ret: %d\n",
 				KERN_ERR, F2FS_I_SB(dic->inode)->sb->s_id,
-				__func__, ZSTD_getErrorCode(ret));
+				__func__, zstd_get_error_code(ret));
 		return -EIO;
 	}
 
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index cf049a042482..78b64bf5e0f7 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -592,7 +592,7 @@ static int f2fs_set_zstd_level(struct f2fs_sb_info *sbi, const char *str)
 	if (kstrtouint(str + 1, 10, &level))
 		return -EINVAL;
 
-	if (!level || level > ZSTD_maxCLevel()) {
+	if (!level || level > zstd_max_clevel()) {
 		f2fs_info(sbi, "invalid zstd compress level: %d", level);
 		return -EINVAL;
 	}