erofs: refine z_erofs_{init,exit}_subsystem()

Introduce z_erofs_{init,exit}_decompressor() to unexport
z_erofs_{deflate,lzma,zstd}_{init,exit}().

Besides, call them in z_erofs_{init,exit}_subsystem()
for simplicity.
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240709094106.3018109-2-hsiangkao@linux.alibaba.com

fs/erofs/compress.h

@@ -24,6 +24,8 @@ struct z_erofs_decompressor {
 		      void *data, int size);
 	int (*decompress)(struct z_erofs_decompress_req *rq,
 			  struct page **pagepool);
+	int (*init)(void);
+	void (*exit)(void);
 	char *name;
 };
 
@@ -88,4 +90,6 @@ extern const struct z_erofs_decompressor *z_erofs_decomp[];
 
 int z_erofs_fixup_insize(struct z_erofs_decompress_req *rq, const char *padbuf,
 			 unsigned int padbufsize);
+int __init z_erofs_init_decompressor(void);
+void z_erofs_exit_decompressor(void);
 #endif

fs/erofs/decompressor.c

@@ -2,6 +2,7 @@
 /*
  * Copyright (C) 2019 HUAWEI, Inc.
  *             https://www.huawei.com/
+ * Copyright (C) 2024 Alibaba Cloud
  */
 #include "compress.h"
 #include <linux/lz4.h>
@@ -383,6 +384,8 @@ const struct z_erofs_decompressor *z_erofs_decomp[] = {
 	[Z_EROFS_COMPRESSION_LZ4] = &(const struct z_erofs_decompressor) {
 		.config = z_erofs_load_lz4_config,
 		.decompress = z_erofs_lz4_decompress,
+		.init = z_erofs_gbuf_init,
+		.exit = z_erofs_gbuf_exit,
 		.name = "lz4"
 	},
 #ifdef CONFIG_EROFS_FS_ZIP_LZMA
@@ -446,3 +449,28 @@ int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb)
 	erofs_put_metabuf(&buf);
 	return ret;
 }
+
+int __init z_erofs_init_decompressor(void)
+{
+	int i, err;
+
+	for (i = 0; i < Z_EROFS_COMPRESSION_MAX; ++i) {
+		err = z_erofs_decomp[i] ? z_erofs_decomp[i]->init() : 0;
+		if (err) {
+			while (--i)
+				if (z_erofs_decomp[i])
+					z_erofs_decomp[i]->exit();
+			return err;
+		}
+	}
+	return 0;
+}
+
+void z_erofs_exit_decompressor(void)
+{
+	int i;
+
+	for (i = 0; i < Z_EROFS_COMPRESSION_MAX; ++i)
+		if (z_erofs_decomp[i])
+			z_erofs_decomp[i]->exit();
+}

fs/erofs/decompressor_deflate.c

@@ -15,7 +15,7 @@ static DECLARE_WAIT_QUEUE_HEAD(z_erofs_deflate_wq);
 
 module_param_named(deflate_streams, z_erofs_deflate_nstrms, uint, 0444);
 
-void z_erofs_deflate_exit(void)
+static void z_erofs_deflate_exit(void)
 {
 	/* there should be no running fs instance */
 	while (z_erofs_deflate_avail_strms) {
@@ -41,7 +41,7 @@ void z_erofs_deflate_exit(void)
 	}
 }
 
-int __init z_erofs_deflate_init(void)
+static int __init z_erofs_deflate_init(void)
 {
 	/* by default, use # of possible CPUs instead */
 	if (!z_erofs_deflate_nstrms)
@@ -256,5 +256,7 @@ static int z_erofs_deflate_decompress(struct z_erofs_decompress_req *rq,
 const struct z_erofs_decompressor z_erofs_deflate_decomp = {
 	.config = z_erofs_load_deflate_config,
 	.decompress = z_erofs_deflate_decompress,
+	.init = z_erofs_deflate_init,
+	.exit = z_erofs_deflate_exit,
 	.name = "deflate",
 };

fs/erofs/decompressor_lzma.c

@@ -18,7 +18,7 @@ static DECLARE_WAIT_QUEUE_HEAD(z_erofs_lzma_wq);
 
 module_param_named(lzma_streams, z_erofs_lzma_nstrms, uint, 0444);
 
-void z_erofs_lzma_exit(void)
+static void z_erofs_lzma_exit(void)
 {
 	/* there should be no running fs instance */
 	while (z_erofs_lzma_avail_strms) {
@@ -46,7 +46,7 @@ void z_erofs_lzma_exit(void)
 	}
 }
 
-int __init z_erofs_lzma_init(void)
+static int __init z_erofs_lzma_init(void)
 {
 	unsigned int i;
 
@@ -297,5 +297,7 @@ static int z_erofs_lzma_decompress(struct z_erofs_decompress_req *rq,
 const struct z_erofs_decompressor z_erofs_lzma_decomp = {
 	.config = z_erofs_load_lzma_config,
 	.decompress = z_erofs_lzma_decompress,
+	.init = z_erofs_lzma_init,
+	.exit = z_erofs_lzma_exit,
 	.name = "lzma"
 };

fs/erofs/decompressor_zstd.c

@@ -34,7 +34,7 @@ static struct z_erofs_zstd *z_erofs_isolate_strms(bool all)
 	return strm;
 }
 
-void z_erofs_zstd_exit(void)
+static void z_erofs_zstd_exit(void)
 {
 	while (z_erofs_zstd_avail_strms) {
 		struct z_erofs_zstd *strm, *n;
@@ -49,7 +49,7 @@ void z_erofs_zstd_exit(void)
 	}
 }
 
-int __init z_erofs_zstd_init(void)
+static int __init z_erofs_zstd_init(void)
 {
 	/* by default, use # of possible CPUs instead */
 	if (!z_erofs_zstd_nstrms)
@@ -281,5 +281,7 @@ static int z_erofs_zstd_decompress(struct z_erofs_decompress_req *rq,
 const struct z_erofs_decompressor z_erofs_zstd_decomp = {
 	.config = z_erofs_load_zstd_config,
 	.decompress = z_erofs_zstd_decompress,
+	.init = z_erofs_zstd_init,
+	.exit = z_erofs_zstd_exit,
 	.name = "zstd",
 };

fs/erofs/internal.h

@@ -454,8 +454,8 @@ void erofs_shrinker_register(struct super_block *sb);
 void erofs_shrinker_unregister(struct super_block *sb);
 int __init erofs_init_shrinker(void);
 void erofs_exit_shrinker(void);
-int __init z_erofs_init_zip_subsystem(void);
-void z_erofs_exit_zip_subsystem(void);
+int __init z_erofs_init_subsystem(void);
+void z_erofs_exit_subsystem(void);
 int erofs_try_to_free_all_cached_folios(struct erofs_sb_info *sbi,
 					struct erofs_workgroup *egrp);
 int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
@@ -472,37 +472,11 @@ static inline void erofs_shrinker_register(struct super_block *sb) {}
 static inline void erofs_shrinker_unregister(struct super_block *sb) {}
 static inline int erofs_init_shrinker(void) { return 0; }
 static inline void erofs_exit_shrinker(void) {}
-static inline int z_erofs_init_zip_subsystem(void) { return 0; }
-static inline void z_erofs_exit_zip_subsystem(void) {}
-static inline int z_erofs_gbuf_init(void) { return 0; }
-static inline void z_erofs_gbuf_exit(void) {}
+static inline int z_erofs_init_subsystem(void) { return 0; }
+static inline void z_erofs_exit_subsystem(void) {}
 static inline int erofs_init_managed_cache(struct super_block *sb) { return 0; }
 #endif	/* !CONFIG_EROFS_FS_ZIP */
 
-#ifdef CONFIG_EROFS_FS_ZIP_LZMA
-int __init z_erofs_lzma_init(void);
-void z_erofs_lzma_exit(void);
-#else
-static inline int z_erofs_lzma_init(void) { return 0; }
-static inline int z_erofs_lzma_exit(void) { return 0; }
-#endif	/* !CONFIG_EROFS_FS_ZIP_LZMA */
-
-#ifdef CONFIG_EROFS_FS_ZIP_DEFLATE
-int __init z_erofs_deflate_init(void);
-void z_erofs_deflate_exit(void);
-#else
-static inline int z_erofs_deflate_init(void) { return 0; }
-static inline int z_erofs_deflate_exit(void) { return 0; }
-#endif	/* !CONFIG_EROFS_FS_ZIP_DEFLATE */
-
-#ifdef CONFIG_EROFS_FS_ZIP_ZSTD
-int __init z_erofs_zstd_init(void);
-void z_erofs_zstd_exit(void);
-#else
-static inline int z_erofs_zstd_init(void) { return 0; }
-static inline int z_erofs_zstd_exit(void) { return 0; }
-#endif	/* !CONFIG_EROFS_FS_ZIP_ZSTD */
-
 #ifdef CONFIG_EROFS_FS_ONDEMAND
 int erofs_fscache_register_fs(struct super_block *sb);
 void erofs_fscache_unregister_fs(struct super_block *sb);

fs/erofs/super.c

@@ -849,23 +849,7 @@ static int __init erofs_module_init(void)
 	if (err)
 		goto shrinker_err;
 
-	err = z_erofs_lzma_init();
-	if (err)
-		goto lzma_err;
-
-	err = z_erofs_deflate_init();
-	if (err)
-		goto deflate_err;
-
-	err = z_erofs_zstd_init();
-	if (err)
-		goto zstd_err;
-
-	err = z_erofs_gbuf_init();
-	if (err)
-		goto gbuf_err;
-
-	err = z_erofs_init_zip_subsystem();
+	err = z_erofs_init_subsystem();
 	if (err)
 		goto zip_err;
 
@@ -882,16 +866,8 @@ static int __init erofs_module_init(void)
 fs_err:
 	erofs_exit_sysfs();
 sysfs_err:
-	z_erofs_exit_zip_subsystem();
+	z_erofs_exit_subsystem();
 zip_err:
-	z_erofs_gbuf_exit();
-gbuf_err:
-	z_erofs_zstd_exit();
-zstd_err:
-	z_erofs_deflate_exit();
-deflate_err:
-	z_erofs_lzma_exit();
-lzma_err:
 	erofs_exit_shrinker();
 shrinker_err:
 	kmem_cache_destroy(erofs_inode_cachep);
@@ -906,13 +882,9 @@ static void __exit erofs_module_exit(void)
 	rcu_barrier();
 
 	erofs_exit_sysfs();
-	z_erofs_exit_zip_subsystem();
-	z_erofs_zstd_exit();
-	z_erofs_deflate_exit();
-	z_erofs_lzma_exit();
+	z_erofs_exit_subsystem();
 	erofs_exit_shrinker();
 	kmem_cache_destroy(erofs_inode_cachep);
-	z_erofs_gbuf_exit();
 }
 
 static int erofs_statfs(struct dentry *dentry, struct kstatfs *buf)

fs/erofs/zdata.c

@@ -446,44 +446,51 @@ static inline int erofs_cpu_hotplug_init(void) { return 0; }
 static inline void erofs_cpu_hotplug_destroy(void) {}
 #endif
 
-void z_erofs_exit_zip_subsystem(void)
+void z_erofs_exit_subsystem(void)
 {
 	erofs_cpu_hotplug_destroy();
 	erofs_destroy_percpu_workers();
 	destroy_workqueue(z_erofs_workqueue);
 	z_erofs_destroy_pcluster_pool();
+	z_erofs_exit_decompressor();
 }
 
-int __init z_erofs_init_zip_subsystem(void)
+int __init z_erofs_init_subsystem(void)
 {
-	int err = z_erofs_create_pcluster_pool();
+	int err = z_erofs_init_decompressor();
 
 	if (err)
-		goto out_error_pcluster_pool;
+		goto err_decompressor;
+
+	err = z_erofs_create_pcluster_pool();
+	if (err)
+		goto err_pcluster_pool;
 
 	z_erofs_workqueue = alloc_workqueue("erofs_worker",
 			WQ_UNBOUND | WQ_HIGHPRI, num_possible_cpus());
 	if (!z_erofs_workqueue) {
 		err = -ENOMEM;
-		goto out_error_workqueue_init;
+		goto err_workqueue_init;
 	}
 
 	err = erofs_init_percpu_workers();
 	if (err)
-		goto out_error_pcpu_worker;
+		goto err_pcpu_worker;
 
 	err = erofs_cpu_hotplug_init();
 	if (err < 0)
-		goto out_error_cpuhp_init;
+		goto err_cpuhp_init;
 	return err;
 
-out_error_cpuhp_init:
+err_cpuhp_init:
 	erofs_destroy_percpu_workers();
-out_error_pcpu_worker:
+err_pcpu_worker:
 	destroy_workqueue(z_erofs_workqueue);
-out_error_workqueue_init:
+err_workqueue_init:
 	z_erofs_destroy_pcluster_pool();
-out_error_pcluster_pool:
+err_pcluster_pool:
+	z_erofs_exit_decompressor();
+err_decompressor:
 	return err;
 }