Re: [PATCH 6.1.y 1/2] erofs: simplify compression configuration parser

Hi Yue,

On 2024/2/27 10:22, Yue Hu wrote:

From: Gao Xiang hsiangkao@linux.alibaba.com

[ Upstream commit efb4fb02cef3ab410b603c8f0e1c67f61d55f542 ]

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.

Reviewed-by: Chao Yu chao@kernel.org Signed-off-by: Gao Xiang hsiangkao@linux.alibaba.com Link: https://lore.kernel.org/r/20231022130957.11398-1-xiang@kernel.org Stable-dep-of: 118a8cf504d7 ("erofs: fix inconsistent per-file compression format") Signed-off-by: Yue Hu huyue2@coolpad.com

where is the real fix [patch 2/2]? It's needed to be posted here too.

Thanks, Gao Xiang

---

fs/erofs/compress.h | 4 ++ fs/erofs/decompressor.c | 60 ++++++++++++++++++++++++++++-- fs/erofs/decompressor_lzma.c | 4 +- fs/erofs/internal.h | 28 ++------------ fs/erofs/super.c | 72 +++++------------------------------- 5 files changed, 76 insertions(+), 92 deletions(-)

diff --git a/fs/erofs/compress.h b/fs/erofs/compress.h index 26fa170090b8..c4a3187bdb8f 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;

@@ -93,6 +95,8 @@ int z_erofs_decompress(struct z_erofs_decompress_req *rq, struct page **pagepool); /* 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_lzma_decompress(struct z_erofs_decompress_req *rq, struct page **pagepool); #endif

diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c index 0cfad74374ca..ae3cfd018d99 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) { @@ -374,17 +374,71 @@ static struct z_erofs_decompressor 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 };

+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;
  

• }
• 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(decompressors) ||
  

•     !decompressors[alg].config) {
  

• 	erofs_err(sb, "algorithm %d isn't enabled on this kernel",
  

• 		  alg);
  

• 	ret = -EOPNOTSUPP;
  

• } else {
  

• 	ret = decompressors[alg].config(sb,
  

• 			dsb, data, size);
  

• }
  

• kfree(data);
  

• if (ret)
  

• 	break;
  

• }
• erofs_put_metabuf(&buf);
• return ret;

+}

• int z_erofs_decompress(struct z_erofs_decompress_req *rq, struct page **pagepool) {

diff --git a/fs/erofs/decompressor_lzma.c b/fs/erofs/decompressor_lzma.c index 49addc345aeb..970464c4b676 100644 --- a/fs/erofs/decompressor_lzma.c +++ b/fs/erofs/decompressor_lzma.c @@ -72,10 +72,10 @@ int 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 d8d09fc3ed65..79a7a5815ea6 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -471,6 +471,8 @@ struct erofs_map_dev { /* data.c */ extern const struct file_operations erofs_file_fops; +void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,

• 	  erofs_off_t *offset, int *lengthp);
  

  void erofs_unmap_metabuf(struct erofs_buf *buf); void erofs_put_metabuf(struct erofs_buf *buf); void *erofs_bread(struct erofs_buf *buf, struct inode *inode,

@@ -565,9 +567,7 @@ 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 erofs_try_to_free_cached_page(struct page *page); -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_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) {} @@ -575,36 +575,14 @@ 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;

-} #endif /* !CONFIG_EROFS_FS_ZIP */ #ifdef CONFIG_EROFS_FS_ZIP_LZMA int 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 */ /* flags for erofs_fscache_register_cookie() */ diff --git a/fs/erofs/super.c b/fs/erofs/super.c index bd8bf8fc2f5d..f2647126cb2f 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -126,8 +126,8 @@ static bool check_layout_compatibility(struct super_block *sb, #ifdef CONFIG_EROFS_FS_ZIP /* read variable-sized metadata, offset will be aligned by 4-byte */ -static void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,

• 		 erofs_off_t *offset, int *lengthp)
  

+void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,

• 	  erofs_off_t *offset, int *lengthp)
  

  { u8 *buffer, *ptr; int len, i, cnt;

@@ -159,64 +159,15 @@ static void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf, } return buffer; }

-static int erofs_load_compr_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;
  

• }
• 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;
  

• }
  

• 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;
  

• 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)
  

+static int z_erofs_parse_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;

• if (!dsb->u1.available_compr_algs)

• return 0;
  

• erofs_err(sb, "compression disabled, unable to mount compressed EROFS");
• return -EOPNOTSUPP; } #endif

@@ -398,10 +349,7 @@ 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;