From 5875bf287d95314c58add01184f361cc5aa38429 Mon Sep 17 00:00:00 2001 From: Tetsuhiro Kohada Date: Fri, 29 May 2020 19:14:59 +0900 Subject: exfat: standardize checksum calculation To clarify that it is a 16-bit checksum, the parts related to the 16-bit checksum are renamed and change type to u16. Furthermore, replace checksum calculation in exfat_load_upcase_table() with exfat_calc_checksum32(). Signed-off-by: Tetsuhiro Kohada Reviewed-by: Sungjong Seo Signed-off-by: Namjae Jeon --- fs/exfat/nls.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) (limited to 'fs/exfat/nls.c') diff --git a/fs/exfat/nls.c b/fs/exfat/nls.c index 1ebda90cbdd7..19321773dd07 100644 --- a/fs/exfat/nls.c +++ b/fs/exfat/nls.c @@ -527,7 +527,7 @@ static int exfat_utf8_to_utf16(struct super_block *sb, *uniname = '\0'; p_uniname->name_len = unilen; - p_uniname->name_hash = exfat_calc_chksum_2byte(upname, unilen << 1, 0, + p_uniname->name_hash = exfat_calc_chksum16(upname, unilen << 1, 0, CS_DEFAULT); if (p_lossy) @@ -623,7 +623,7 @@ static int exfat_nls_to_ucs2(struct super_block *sb, *uniname = '\0'; p_uniname->name_len = unilen; - p_uniname->name_hash = exfat_calc_chksum_2byte(upname, unilen << 1, 0, + p_uniname->name_hash = exfat_calc_chksum16(upname, unilen << 1, 0, CS_DEFAULT); if (p_lossy) @@ -655,7 +655,8 @@ static int exfat_load_upcase_table(struct super_block *sb, { struct exfat_sb_info *sbi = EXFAT_SB(sb); unsigned int sect_size = sb->s_blocksize; - unsigned int i, index = 0, checksum = 0; + unsigned int i, index = 0; + u32 chksum = 0; int ret; unsigned char skip = false; unsigned short *upcase_table; @@ -681,13 +682,6 @@ static int exfat_load_upcase_table(struct super_block *sb, for (i = 0; i < sect_size && index <= 0xFFFF; i += 2) { unsigned short uni = get_unaligned_le16(bh->b_data + i); - checksum = ((checksum & 1) ? 0x80000000 : 0) + - (checksum >> 1) + - *(((unsigned char *)bh->b_data) + i); - checksum = ((checksum & 1) ? 0x80000000 : 0) + - (checksum >> 1) + - *(((unsigned char *)bh->b_data) + (i + 1)); - if (skip) { index += uni; skip = false; @@ -701,13 +695,14 @@ static int exfat_load_upcase_table(struct super_block *sb, } } brelse(bh); + chksum = exfat_calc_chksum32(bh->b_data, i, chksum, CS_DEFAULT); } - if (index >= 0xFFFF && utbl_checksum == checksum) + if (index >= 0xFFFF && utbl_checksum == chksum) return 0; exfat_err(sb, "failed to load upcase table (idx : 0x%08x, chksum : 0x%08x, utbl_chksum : 0x%08x)", - index, checksum, utbl_checksum); + index, chksum, utbl_checksum); ret = -EINVAL; free_table: exfat_free_upcase_table(sbi); -- cgit v1.2.1