From 9010dbc007b853ed55905e40fa8e9d39fcb75935 Mon Sep 17 00:00:00 2001 From: Mikhail Zaslonko Date: Thu, 26 Jan 2023 14:14:27 +0100 Subject: lib/zlib: DFLTCC support inflate with small window There is no hardware control for DFLTCC window size. After this change, software and hardware window formats no longer match: the software will use wbits and wsize, and the hardware will use HB_BITS and HB_SIZE. Since neither dictionary manipulation nor internal allocation functions are relevant to kernel zlib and zlib_inflate_workspacesize() always use MAX_WBITS for window size calculation, only dfltcc_can_inflate() and dfltcc_inflate() functions are affected by this patch. This commit is based on: https://github.com/zlib-ng/zlib-ng/commit/3eab317 Link: https://lkml.kernel.org/r/20230126131428.1222214-8-zaslonko@linux.ibm.com Signed-off-by: Mikhail Zaslonko Acked-by: Ilya Leoshkevich Cc: Heiko Carstens Cc: Vasily Gorbik Signed-off-by: Andrew Morton --- lib/zlib_dfltcc/dfltcc_inflate.c | 8 -------- 1 file changed, 8 deletions(-) (limited to 'lib/zlib_dfltcc') diff --git a/lib/zlib_dfltcc/dfltcc_inflate.c b/lib/zlib_dfltcc/dfltcc_inflate.c index a16f416c8811..5786030c6dc2 100644 --- a/lib/zlib_dfltcc/dfltcc_inflate.c +++ b/lib/zlib_dfltcc/dfltcc_inflate.c @@ -22,10 +22,6 @@ int dfltcc_can_inflate( zlib_dfltcc_support == ZLIB_DFLTCC_DEFLATE_ONLY) return 0; - /* Unsupported compression settings */ - if (state->wbits != HB_BITS) - return 0; - /* Unsupported hardware */ return is_bit_set(dfltcc_state->af.fns, DFLTCC_XPND) && is_bit_set(dfltcc_state->af.fmts, DFLTCC_FMT0); @@ -129,8 +125,6 @@ dfltcc_inflate_action dfltcc_inflate( /* Translate stream to parameter block */ param->cvt = CVT_ADLER32; param->sbb = state->bits; - param->hl = state->whave; /* Software and hardware history formats match */ - param->ho = (state->write - state->whave) & ((1 << HB_BITS) - 1); if (param->hl) param->nt = 0; /* Honor history for the first block */ param->cv = state->check; @@ -144,8 +138,6 @@ dfltcc_inflate_action dfltcc_inflate( strm->msg = oesc_msg(dfltcc_state->msg, param->oesc); state->last = cc == DFLTCC_CC_OK; state->bits = param->sbb; - state->whave = param->hl; - state->write = (param->ho + param->hl) & ((1 << HB_BITS) - 1); state->check = param->cv; if (cc == DFLTCC_CC_OP2_CORRUPT && param->oesc != 0) { /* Report an error if stream is corrupted */ -- cgit