lib/zlib: Split deflate and inflate states for DFLTCC

Currently deflate and inflate both use a common state struct. There are
several variables in this struct that we don't need for inflate, and
more may be coming in the future. Therefore split them in two separate
structs.
Apart from that, introduce separate headers for dfltcc_deflate and
dfltcc_inflate.

This commit is based on:
  https://github.com/zlib-ng/zlib-ng/commit/c592b1b

Link: https://lkml.kernel.org/r/20230126131428.1222214-7-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 27 insertions, 8 deletions

diff --git a/lib/zlib_dfltcc/dfltcc_deflate.c b/lib/zlib_dfltcc/dfltcc_deflate.c
index d4c92f99808e..80924f067c24 100644
--- a/lib/zlib_dfltcc/dfltcc_deflate.c
+++ b/lib/zlib_dfltcc/dfltcc_deflate.c
@@ -2,11 +2,13 @@
 
 #include "../zlib_deflate/defutil.h"
 #include "dfltcc_util.h"
-#include "dfltcc.h"
+#include "dfltcc_deflate.h"
 #include <asm/setup.h>
 #include <linux/export.h>
 #include <linux/zutil.h>
 
+#define GET_DFLTCC_DEFLATE_STATE(state) ((struct dfltcc_deflate_state *)GET_DFLTCC_STATE(state))
+
 /*
  * Compress.
  */
@@ -15,7 +17,7 @@ int dfltcc_can_deflate(
 )
 {
     deflate_state *state = (deflate_state *)strm->state;
-    struct dfltcc_state *dfltcc_state = GET_DFLTCC_STATE(state);
+    struct dfltcc_deflate_state *dfltcc_state = GET_DFLTCC_DEFLATE_STATE(state);
 
     /* Check for kernel dfltcc command line parameter */
     if (zlib_dfltcc_support == ZLIB_DFLTCC_DISABLED ||
@@ -28,15 +30,32 @@ int dfltcc_can_deflate(
         return 0;
 
     /* Unsupported hardware */
-    if (!is_bit_set(dfltcc_state->af.fns, DFLTCC_GDHT) ||
-            !is_bit_set(dfltcc_state->af.fns, DFLTCC_CMPR) ||
-            !is_bit_set(dfltcc_state->af.fmts, DFLTCC_FMT0))
+    if (!is_bit_set(dfltcc_state->common.af.fns, DFLTCC_GDHT) ||
+            !is_bit_set(dfltcc_state->common.af.fns, DFLTCC_CMPR) ||
+            !is_bit_set(dfltcc_state->common.af.fmts, DFLTCC_FMT0))
         return 0;
 
     return 1;
 }
 EXPORT_SYMBOL(dfltcc_can_deflate);
 
+void dfltcc_reset_deflate_state(z_streamp strm) {
+    deflate_state *state = (deflate_state *)strm->state;
+    struct dfltcc_deflate_state *dfltcc_state = GET_DFLTCC_DEFLATE_STATE(state);
+
+    dfltcc_reset_state(&dfltcc_state->common);
+
+    /* Initialize tuning parameters */
+    if (zlib_dfltcc_support == ZLIB_DFLTCC_FULL_DEBUG)
+        dfltcc_state->level_mask = DFLTCC_LEVEL_MASK_DEBUG;
+    else
+        dfltcc_state->level_mask = DFLTCC_LEVEL_MASK;
+    dfltcc_state->block_size = DFLTCC_BLOCK_SIZE;
+    dfltcc_state->block_threshold = DFLTCC_FIRST_FHT_BLOCK_SIZE;
+    dfltcc_state->dht_threshold = DFLTCC_DHT_MIN_SAMPLE_SIZE;
+}
+EXPORT_SYMBOL(dfltcc_reset_deflate_state);
+
 static void dfltcc_gdht(
     z_streamp strm
 )
@@ -104,8 +123,8 @@ int dfltcc_deflate(
 )
 {
     deflate_state *state = (deflate_state *)strm->state;
-    struct dfltcc_state *dfltcc_state = GET_DFLTCC_STATE(state);
-    struct dfltcc_param_v0 *param = &dfltcc_state->param;
+    struct dfltcc_deflate_state *dfltcc_state = GET_DFLTCC_DEFLATE_STATE(state);
+    struct dfltcc_param_v0 *param = &dfltcc_state->common.param;
     uInt masked_avail_in;
     dfltcc_cc cc;
     int need_empty_block;
@@ -244,7 +263,7 @@ again:
     } while (cc == DFLTCC_CC_AGAIN);
 
     /* Translate parameter block to stream */
-    strm->msg = oesc_msg(dfltcc_state->msg, param->oesc);
+    strm->msg = oesc_msg(dfltcc_state->common.msg, param->oesc);
     state->bi_valid = param->sbb;
     if (state->bi_valid == 0)
         state->bi_buf = 0; /* Avoid accessing next_out */