2023-10-21 02:02:09

by Gao Xiang

[permalink] [raw]
Subject: [PATCH] erofs: simplify compression configuration parser

Move erofs_load_compr_cfgs() into decompressor.c as well as introduce
a callback instead of a hard-coded switch for each algorithm for
simplicity.

Signed-off-by: Gao Xiang <[email protected]>
---
fs/erofs/compress.h | 6 +++
fs/erofs/decompressor.c | 60 ++++++++++++++++++++++++++-
fs/erofs/decompressor_deflate.c | 5 ++-
fs/erofs/decompressor_lzma.c | 4 +-
fs/erofs/internal.h | 38 +----------------
fs/erofs/super.c | 72 ++++-----------------------------
6 files changed, 78 insertions(+), 107 deletions(-)

diff --git a/fs/erofs/compress.h b/fs/erofs/compress.h
index 349c3316ae6b..279933e007d2 100644
--- a/fs/erofs/compress.h
+++ b/fs/erofs/compress.h
@@ -21,6 +21,8 @@ struct z_erofs_decompress_req {
};

struct z_erofs_decompressor {
+ int (*config)(struct super_block *sb, struct erofs_super_block *dsb,
+ void *data, int size);
int (*decompress)(struct z_erofs_decompress_req *rq,
struct page **pagepool);
char *name;
@@ -92,6 +94,10 @@ int z_erofs_fixup_insize(struct z_erofs_decompress_req *rq, const char *padbuf,
extern const struct z_erofs_decompressor erofs_decompressors[];

/* prototypes for specific algorithms */
+int z_erofs_load_lzma_config(struct super_block *sb,
+ struct erofs_super_block *dsb, void *data, int size);
+int z_erofs_load_deflate_config(struct super_block *sb,
+ struct erofs_super_block *dsb, void *data, int size);
int z_erofs_lzma_decompress(struct z_erofs_decompress_req *rq,
struct page **pagepool);
int z_erofs_deflate_decompress(struct z_erofs_decompress_req *rq,
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index 332ec5f74002..6cb57e45c180 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -25,10 +25,10 @@ struct z_erofs_lz4_decompress_ctx {
};

int z_erofs_load_lz4_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lz4_cfgs *lz4, int size)
+ struct erofs_super_block *dsb, void *data, int size)
{
struct erofs_sb_info *sbi = EROFS_SB(sb);
+ struct z_erofs_lz4_cfgs *lz4 = data;
u16 distance;

if (lz4) {
@@ -370,19 +370,75 @@ const struct z_erofs_decompressor erofs_decompressors[] = {
.name = "interlaced"
},
[Z_EROFS_COMPRESSION_LZ4] = {
+ .config = z_erofs_load_lz4_config,
.decompress = z_erofs_lz4_decompress,
.name = "lz4"
},
#ifdef CONFIG_EROFS_FS_ZIP_LZMA
[Z_EROFS_COMPRESSION_LZMA] = {
+ .config = z_erofs_load_lzma_config,
.decompress = z_erofs_lzma_decompress,
.name = "lzma"
},
#endif
#ifdef CONFIG_EROFS_FS_ZIP_DEFLATE
[Z_EROFS_COMPRESSION_DEFLATE] = {
+ .config = z_erofs_load_deflate_config,
.decompress = z_erofs_deflate_decompress,
.name = "deflate"
},
#endif
};
+
+int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb)
+{
+ struct erofs_sb_info *sbi = EROFS_SB(sb);
+ struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
+ unsigned int algs, alg;
+ erofs_off_t offset;
+ int size, ret = 0;
+
+ if (!erofs_sb_has_compr_cfgs(sbi)) {
+ sbi->available_compr_algs = Z_EROFS_COMPRESSION_LZ4;
+ return z_erofs_load_lz4_config(sb, dsb, NULL, 0);
+ }
+
+ sbi->available_compr_algs = le16_to_cpu(dsb->u1.available_compr_algs);
+ if (sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS) {
+ erofs_err(sb, "unidentified algorithms %x, please upgrade kernel",
+ sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS);
+ return -EOPNOTSUPP;
+ }
+
+ erofs_init_metabuf(&buf, sb);
+ offset = EROFS_SUPER_OFFSET + sbi->sb_size;
+ alg = 0;
+ for (algs = sbi->available_compr_algs; algs; algs >>= 1, ++alg) {
+ void *data;
+
+ if (!(algs & 1))
+ continue;
+
+ data = erofs_read_metadata(sb, &buf, &offset, &size);
+ if (IS_ERR(data)) {
+ ret = PTR_ERR(data);
+ break;
+ }
+
+ if (alg >= ARRAY_SIZE(erofs_decompressors) ||
+ !erofs_decompressors[alg].config) {
+ erofs_err(sb, "algorithm %d isn't enabled on this kernel",
+ alg);
+ ret = -EOPNOTSUPP;
+ } else {
+ ret = erofs_decompressors[alg].config(sb,
+ dsb, data, size);
+ }
+
+ kfree(data);
+ if (ret)
+ break;
+ }
+ erofs_put_metabuf(&buf);
+ return ret;
+}
diff --git a/fs/erofs/decompressor_deflate.c b/fs/erofs/decompressor_deflate.c
index 19e5bdeb30b6..0e1946a6bda5 100644
--- a/fs/erofs/decompressor_deflate.c
+++ b/fs/erofs/decompressor_deflate.c
@@ -77,9 +77,10 @@ int __init z_erofs_deflate_init(void)
}

int z_erofs_load_deflate_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_deflate_cfgs *dfl, int size)
+ struct erofs_super_block *dsb, void *data, int size)
{
+ struct z_erofs_deflate_cfgs *dfl = data;
+
if (!dfl || size < sizeof(struct z_erofs_deflate_cfgs)) {
erofs_err(sb, "invalid deflate cfgs, size=%u", size);
return -EINVAL;
diff --git a/fs/erofs/decompressor_lzma.c b/fs/erofs/decompressor_lzma.c
index dee10d22ada9..ba4ec73f4aae 100644
--- a/fs/erofs/decompressor_lzma.c
+++ b/fs/erofs/decompressor_lzma.c
@@ -72,10 +72,10 @@ int __init z_erofs_lzma_init(void)
}

int z_erofs_load_lzma_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lzma_cfgs *lzma, int size)
+ struct erofs_super_block *dsb, void *data, int size)
{
static DEFINE_MUTEX(lzma_resize_mutex);
+ struct z_erofs_lzma_cfgs *lzma = data;
unsigned int dict_size, i;
struct z_erofs_lzma *strm, *head = NULL;
int err;
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 4ff88d0dd980..d8de61350dc0 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -469,9 +469,6 @@ int __init z_erofs_init_zip_subsystem(void);
void z_erofs_exit_zip_subsystem(void);
int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
struct erofs_workgroup *egrp);
-int z_erofs_load_lz4_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lz4_cfgs *lz4, int len);
int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
int flags);
void *erofs_get_pcpubuf(unsigned int requiredpages);
@@ -480,6 +477,7 @@ int erofs_pcpubuf_growsize(unsigned int nrpages);
void __init erofs_pcpubuf_init(void);
void erofs_pcpubuf_exit(void);
int erofs_init_managed_cache(struct super_block *sb);
+int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb);
#else
static inline void erofs_shrinker_register(struct super_block *sb) {}
static inline void erofs_shrinker_unregister(struct super_block *sb) {}
@@ -487,16 +485,6 @@ 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_load_lz4_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lz4_cfgs *lz4, int len)
-{
- if (lz4 || dsb->u1.lz4_max_distance) {
- erofs_err(sb, "lz4 algorithm isn't enabled");
- return -EINVAL;
- }
- return 0;
-}
static inline void erofs_pcpubuf_init(void) {}
static inline void erofs_pcpubuf_exit(void) {}
static inline int erofs_init_managed_cache(struct super_block *sb) { return 0; }
@@ -505,41 +493,17 @@ static inline int erofs_init_managed_cache(struct super_block *sb) { return 0; }
#ifdef CONFIG_EROFS_FS_ZIP_LZMA
int __init z_erofs_lzma_init(void);
void z_erofs_lzma_exit(void);
-int z_erofs_load_lzma_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lzma_cfgs *lzma, int size);
#else
static inline int z_erofs_lzma_init(void) { return 0; }
static inline int z_erofs_lzma_exit(void) { return 0; }
-static inline int z_erofs_load_lzma_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lzma_cfgs *lzma, int size) {
- if (lzma) {
- erofs_err(sb, "lzma algorithm isn't enabled");
- return -EINVAL;
- }
- 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);
-int z_erofs_load_deflate_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_deflate_cfgs *dfl, int size);
#else
static inline int z_erofs_deflate_init(void) { return 0; }
static inline int z_erofs_deflate_exit(void) { return 0; }
-static inline int z_erofs_load_deflate_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_deflate_cfgs *dfl, int size) {
- if (dfl) {
- erofs_err(sb, "deflate algorithm isn't enabled");
- return -EINVAL;
- }
- return 0;
-}
#endif /* !CONFIG_EROFS_FS_ZIP_DEFLATE */

#ifdef CONFIG_EROFS_FS_ONDEMAND
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 3700af9ee173..cc44fb2e001e 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -156,68 +156,15 @@ void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,
return buffer;
}

-#ifdef CONFIG_EROFS_FS_ZIP
-static int erofs_load_compr_cfgs(struct super_block *sb,
- struct erofs_super_block *dsb)
+#ifndef CONFIG_EROFS_FS_ZIP
+static int z_erofs_parse_cfgs(struct super_block *sb,
+ struct erofs_super_block *dsb)
{
- struct erofs_sb_info *sbi = EROFS_SB(sb);
- struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
- unsigned int algs, alg;
- erofs_off_t offset;
- int size, ret = 0;
-
- sbi->available_compr_algs = le16_to_cpu(dsb->u1.available_compr_algs);
- if (sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS) {
- erofs_err(sb, "try to load compressed fs with unsupported algorithms %x",
- sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS);
- return -EINVAL;
- }
-
- erofs_init_metabuf(&buf, sb);
- offset = EROFS_SUPER_OFFSET + sbi->sb_size;
- alg = 0;
- for (algs = sbi->available_compr_algs; algs; algs >>= 1, ++alg) {
- void *data;
-
- if (!(algs & 1))
- continue;
-
- data = erofs_read_metadata(sb, &buf, &offset, &size);
- if (IS_ERR(data)) {
- ret = PTR_ERR(data);
- break;
- }
+ if (!dsb->u1.available_compr_algs)
+ return 0;

- switch (alg) {
- case Z_EROFS_COMPRESSION_LZ4:
- ret = z_erofs_load_lz4_config(sb, dsb, data, size);
- break;
- case Z_EROFS_COMPRESSION_LZMA:
- ret = z_erofs_load_lzma_config(sb, dsb, data, size);
- break;
- case Z_EROFS_COMPRESSION_DEFLATE:
- ret = z_erofs_load_deflate_config(sb, dsb, data, size);
- break;
- default:
- DBG_BUGON(1);
- ret = -EFAULT;
- }
- kfree(data);
- if (ret)
- break;
- }
- erofs_put_metabuf(&buf);
- return ret;
-}
-#else
-static int erofs_load_compr_cfgs(struct super_block *sb,
- struct erofs_super_block *dsb)
-{
- if (dsb->u1.available_compr_algs) {
- erofs_err(sb, "try to load compressed fs when compression is disabled");
- return -EINVAL;
- }
- return 0;
+ erofs_err(sb, "compression disabled, unable to mount compressed EROFS");
+ return -EOPNOTSUPP;
}
#endif

@@ -406,10 +353,7 @@ static int erofs_read_superblock(struct super_block *sb)
}

/* parse on-disk compression configurations */
- if (erofs_sb_has_compr_cfgs(sbi))
- ret = erofs_load_compr_cfgs(sb, dsb);
- else
- ret = z_erofs_load_lz4_config(sb, dsb, NULL, 0);
+ ret = z_erofs_parse_cfgs(sb, dsb);
if (ret < 0)
goto out;

--
2.39.3


2023-10-22 13:12:21

by Gao Xiang

[permalink] [raw]
Subject: [PATCH v2] erofs: simplify compression configuration parser

From: Gao Xiang <[email protected]>

Move erofs_load_compr_cfgs() into decompressor.c as well as introduce
a callback instead of a hard-coded switch for each algorithm for
simplicity.

Signed-off-by: Gao Xiang <[email protected]>
---
v2:
- fix build warning of `-Wmissing-declarations`
https://lore.kernel.org/r/[email protected]

fs/erofs/compress.h | 6 +++
fs/erofs/decompressor.c | 62 ++++++++++++++++++++++++++--
fs/erofs/decompressor_deflate.c | 5 ++-
fs/erofs/decompressor_lzma.c | 4 +-
fs/erofs/internal.h | 38 +----------------
fs/erofs/super.c | 72 ++++-----------------------------
6 files changed, 79 insertions(+), 108 deletions(-)

diff --git a/fs/erofs/compress.h b/fs/erofs/compress.h
index 349c3316ae6b..279933e007d2 100644
--- a/fs/erofs/compress.h
+++ b/fs/erofs/compress.h
@@ -21,6 +21,8 @@ struct z_erofs_decompress_req {
};

struct z_erofs_decompressor {
+ int (*config)(struct super_block *sb, struct erofs_super_block *dsb,
+ void *data, int size);
int (*decompress)(struct z_erofs_decompress_req *rq,
struct page **pagepool);
char *name;
@@ -92,6 +94,10 @@ int z_erofs_fixup_insize(struct z_erofs_decompress_req *rq, const char *padbuf,
extern const struct z_erofs_decompressor erofs_decompressors[];

/* prototypes for specific algorithms */
+int z_erofs_load_lzma_config(struct super_block *sb,
+ struct erofs_super_block *dsb, void *data, int size);
+int z_erofs_load_deflate_config(struct super_block *sb,
+ struct erofs_super_block *dsb, void *data, int size);
int z_erofs_lzma_decompress(struct z_erofs_decompress_req *rq,
struct page **pagepool);
int z_erofs_deflate_decompress(struct z_erofs_decompress_req *rq,
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index 332ec5f74002..e75edc8f1753 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -24,11 +24,11 @@ struct z_erofs_lz4_decompress_ctx {
unsigned int oend;
};

-int z_erofs_load_lz4_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lz4_cfgs *lz4, int size)
+static int z_erofs_load_lz4_config(struct super_block *sb,
+ struct erofs_super_block *dsb, void *data, int size)
{
struct erofs_sb_info *sbi = EROFS_SB(sb);
+ struct z_erofs_lz4_cfgs *lz4 = data;
u16 distance;

if (lz4) {
@@ -370,19 +370,75 @@ const struct z_erofs_decompressor erofs_decompressors[] = {
.name = "interlaced"
},
[Z_EROFS_COMPRESSION_LZ4] = {
+ .config = z_erofs_load_lz4_config,
.decompress = z_erofs_lz4_decompress,
.name = "lz4"
},
#ifdef CONFIG_EROFS_FS_ZIP_LZMA
[Z_EROFS_COMPRESSION_LZMA] = {
+ .config = z_erofs_load_lzma_config,
.decompress = z_erofs_lzma_decompress,
.name = "lzma"
},
#endif
#ifdef CONFIG_EROFS_FS_ZIP_DEFLATE
[Z_EROFS_COMPRESSION_DEFLATE] = {
+ .config = z_erofs_load_deflate_config,
.decompress = z_erofs_deflate_decompress,
.name = "deflate"
},
#endif
};
+
+int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb)
+{
+ struct erofs_sb_info *sbi = EROFS_SB(sb);
+ struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
+ unsigned int algs, alg;
+ erofs_off_t offset;
+ int size, ret = 0;
+
+ if (!erofs_sb_has_compr_cfgs(sbi)) {
+ sbi->available_compr_algs = Z_EROFS_COMPRESSION_LZ4;
+ return z_erofs_load_lz4_config(sb, dsb, NULL, 0);
+ }
+
+ sbi->available_compr_algs = le16_to_cpu(dsb->u1.available_compr_algs);
+ if (sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS) {
+ erofs_err(sb, "unidentified algorithms %x, please upgrade kernel",
+ sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS);
+ return -EOPNOTSUPP;
+ }
+
+ erofs_init_metabuf(&buf, sb);
+ offset = EROFS_SUPER_OFFSET + sbi->sb_size;
+ alg = 0;
+ for (algs = sbi->available_compr_algs; algs; algs >>= 1, ++alg) {
+ void *data;
+
+ if (!(algs & 1))
+ continue;
+
+ data = erofs_read_metadata(sb, &buf, &offset, &size);
+ if (IS_ERR(data)) {
+ ret = PTR_ERR(data);
+ break;
+ }
+
+ if (alg >= ARRAY_SIZE(erofs_decompressors) ||
+ !erofs_decompressors[alg].config) {
+ erofs_err(sb, "algorithm %d isn't enabled on this kernel",
+ alg);
+ ret = -EOPNOTSUPP;
+ } else {
+ ret = erofs_decompressors[alg].config(sb,
+ dsb, data, size);
+ }
+
+ kfree(data);
+ if (ret)
+ break;
+ }
+ erofs_put_metabuf(&buf);
+ return ret;
+}
diff --git a/fs/erofs/decompressor_deflate.c b/fs/erofs/decompressor_deflate.c
index 19e5bdeb30b6..0e1946a6bda5 100644
--- a/fs/erofs/decompressor_deflate.c
+++ b/fs/erofs/decompressor_deflate.c
@@ -77,9 +77,10 @@ int __init z_erofs_deflate_init(void)
}

int z_erofs_load_deflate_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_deflate_cfgs *dfl, int size)
+ struct erofs_super_block *dsb, void *data, int size)
{
+ struct z_erofs_deflate_cfgs *dfl = data;
+
if (!dfl || size < sizeof(struct z_erofs_deflate_cfgs)) {
erofs_err(sb, "invalid deflate cfgs, size=%u", size);
return -EINVAL;
diff --git a/fs/erofs/decompressor_lzma.c b/fs/erofs/decompressor_lzma.c
index 5f413f19a064..852dd8eac5df 100644
--- a/fs/erofs/decompressor_lzma.c
+++ b/fs/erofs/decompressor_lzma.c
@@ -72,10 +72,10 @@ int __init z_erofs_lzma_init(void)
}

int z_erofs_load_lzma_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lzma_cfgs *lzma, int size)
+ struct erofs_super_block *dsb, void *data, int size)
{
static DEFINE_MUTEX(lzma_resize_mutex);
+ struct z_erofs_lzma_cfgs *lzma = data;
unsigned int dict_size, i;
struct z_erofs_lzma *strm, *head = NULL;
int err;
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 4ff88d0dd980..d8de61350dc0 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -469,9 +469,6 @@ int __init z_erofs_init_zip_subsystem(void);
void z_erofs_exit_zip_subsystem(void);
int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
struct erofs_workgroup *egrp);
-int z_erofs_load_lz4_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lz4_cfgs *lz4, int len);
int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
int flags);
void *erofs_get_pcpubuf(unsigned int requiredpages);
@@ -480,6 +477,7 @@ int erofs_pcpubuf_growsize(unsigned int nrpages);
void __init erofs_pcpubuf_init(void);
void erofs_pcpubuf_exit(void);
int erofs_init_managed_cache(struct super_block *sb);
+int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb);
#else
static inline void erofs_shrinker_register(struct super_block *sb) {}
static inline void erofs_shrinker_unregister(struct super_block *sb) {}
@@ -487,16 +485,6 @@ 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_load_lz4_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lz4_cfgs *lz4, int len)
-{
- if (lz4 || dsb->u1.lz4_max_distance) {
- erofs_err(sb, "lz4 algorithm isn't enabled");
- return -EINVAL;
- }
- return 0;
-}
static inline void erofs_pcpubuf_init(void) {}
static inline void erofs_pcpubuf_exit(void) {}
static inline int erofs_init_managed_cache(struct super_block *sb) { return 0; }
@@ -505,41 +493,17 @@ static inline int erofs_init_managed_cache(struct super_block *sb) { return 0; }
#ifdef CONFIG_EROFS_FS_ZIP_LZMA
int __init z_erofs_lzma_init(void);
void z_erofs_lzma_exit(void);
-int z_erofs_load_lzma_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lzma_cfgs *lzma, int size);
#else
static inline int z_erofs_lzma_init(void) { return 0; }
static inline int z_erofs_lzma_exit(void) { return 0; }
-static inline int z_erofs_load_lzma_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_lzma_cfgs *lzma, int size) {
- if (lzma) {
- erofs_err(sb, "lzma algorithm isn't enabled");
- return -EINVAL;
- }
- 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);
-int z_erofs_load_deflate_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_deflate_cfgs *dfl, int size);
#else
static inline int z_erofs_deflate_init(void) { return 0; }
static inline int z_erofs_deflate_exit(void) { return 0; }
-static inline int z_erofs_load_deflate_config(struct super_block *sb,
- struct erofs_super_block *dsb,
- struct z_erofs_deflate_cfgs *dfl, int size) {
- if (dfl) {
- erofs_err(sb, "deflate algorithm isn't enabled");
- return -EINVAL;
- }
- return 0;
-}
#endif /* !CONFIG_EROFS_FS_ZIP_DEFLATE */

#ifdef CONFIG_EROFS_FS_ONDEMAND
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 3700af9ee173..cc44fb2e001e 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -156,68 +156,15 @@ void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,
return buffer;
}

-#ifdef CONFIG_EROFS_FS_ZIP
-static int erofs_load_compr_cfgs(struct super_block *sb,
- struct erofs_super_block *dsb)
+#ifndef CONFIG_EROFS_FS_ZIP
+static int z_erofs_parse_cfgs(struct super_block *sb,
+ struct erofs_super_block *dsb)
{
- struct erofs_sb_info *sbi = EROFS_SB(sb);
- struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
- unsigned int algs, alg;
- erofs_off_t offset;
- int size, ret = 0;
-
- sbi->available_compr_algs = le16_to_cpu(dsb->u1.available_compr_algs);
- if (sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS) {
- erofs_err(sb, "try to load compressed fs with unsupported algorithms %x",
- sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS);
- return -EINVAL;
- }
-
- erofs_init_metabuf(&buf, sb);
- offset = EROFS_SUPER_OFFSET + sbi->sb_size;
- alg = 0;
- for (algs = sbi->available_compr_algs; algs; algs >>= 1, ++alg) {
- void *data;
-
- if (!(algs & 1))
- continue;
-
- data = erofs_read_metadata(sb, &buf, &offset, &size);
- if (IS_ERR(data)) {
- ret = PTR_ERR(data);
- break;
- }
+ if (!dsb->u1.available_compr_algs)
+ return 0;

- switch (alg) {
- case Z_EROFS_COMPRESSION_LZ4:
- ret = z_erofs_load_lz4_config(sb, dsb, data, size);
- break;
- case Z_EROFS_COMPRESSION_LZMA:
- ret = z_erofs_load_lzma_config(sb, dsb, data, size);
- break;
- case Z_EROFS_COMPRESSION_DEFLATE:
- ret = z_erofs_load_deflate_config(sb, dsb, data, size);
- break;
- default:
- DBG_BUGON(1);
- ret = -EFAULT;
- }
- kfree(data);
- if (ret)
- break;
- }
- erofs_put_metabuf(&buf);
- return ret;
-}
-#else
-static int erofs_load_compr_cfgs(struct super_block *sb,
- struct erofs_super_block *dsb)
-{
- if (dsb->u1.available_compr_algs) {
- erofs_err(sb, "try to load compressed fs when compression is disabled");
- return -EINVAL;
- }
- return 0;
+ erofs_err(sb, "compression disabled, unable to mount compressed EROFS");
+ return -EOPNOTSUPP;
}
#endif

@@ -406,10 +353,7 @@ static int erofs_read_superblock(struct super_block *sb)
}

/* parse on-disk compression configurations */
- if (erofs_sb_has_compr_cfgs(sbi))
- ret = erofs_load_compr_cfgs(sb, dsb);
- else
- ret = z_erofs_load_lz4_config(sb, dsb, NULL, 0);
+ ret = z_erofs_parse_cfgs(sb, dsb);
if (ret < 0)
goto out;

--
2.30.2

2023-10-30 15:02:18

by Chao Yu

[permalink] [raw]
Subject: Re: [PATCH v2] erofs: simplify compression configuration parser

On 2023/10/22 21:09, Gao Xiang wrote:
> From: Gao Xiang <[email protected]>
>
> Move erofs_load_compr_cfgs() into decompressor.c as well as introduce
> a callback instead of a hard-coded switch for each algorithm for
> simplicity.
>
> Signed-off-by: Gao Xiang <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,