get rid of dynamic buffer struct allocation during pcomp lzma decompression and inste...

[openwrt/openwrt.git] / target / linux / generic-2.6 / patches-2.6.30 / 052-pcomp_lzma_support.patch

diff --git a/target/linux/generic-2.6/patches-2.6.30/052-pcomp_lzma_support.patch b/target/linux/generic-2.6/patches-2.6.30/052-pcomp_lzma_support.patch
index 75dfc376a6597e22eac86b40505377bc10f4aec8..afb37a80cd49beab70eae983f1e2961588ba4381 100644 (file)
--- a/target/linux/generic-2.6/patches-2.6.30/052-pcomp_lzma_support.patch
+++ b/target/linux/generic-2.6/patches-2.6.30/052-pcomp_lzma_support.patch
@@ -1,6 +1,6 @@
 --- /dev/null
 +++ b/crypto/unlzma.c
-@@ -0,0 +1,723 @@
+@@ -0,0 +1,748 @@
 +/*
 + * LZMA uncompresion module for pcomp
 + * Copyright (C) 2009  Felix Fietkau <nbd@openwrt.org>
@@ -36,12 +36,12 @@
 +#include <linux/kthread.h>
 +
 +#include <crypto/internal/compress.h>
++#include <net/netlink.h>
 +#include "unlzma.h"
 +
 +static int instance = 0;
 +
 +struct unlzma_buffer {
-+      struct unlzma_buffer *last;
 +      int offset;
 +      int size;
 +      u8 *ptr;
@@ -68,8 +68,10 @@
 +      /* writer state */
 +      u8 previous_byte;
 +      ssize_t pos;
-+      struct unlzma_buffer *head;
 +      int buf_full;
++      int n_buffers;
++      int buffers_max;
++      struct unlzma_buffer *buffers;
 +
 +      /* cstate */
 +      int state;
@@ -92,12 +94,11 @@
 +{
 +      struct unlzma_buffer *bh;
 +
-+      bh = kzalloc(sizeof(struct unlzma_buffer), GFP_KERNEL);
++      BUG_ON(ctx->n_buffers >= ctx->buffers_max);
++      bh = &ctx->buffers[ctx->n_buffers++];
 +      bh->ptr = ctx->next_out;
 +      bh->offset = ctx->pos;
-+      bh->last = ctx->head;
 +      bh->size = ctx->avail_out;
-+      ctx->head = bh;
 +      ctx->buf_full = 0;
 +}
 +
@@ -208,17 +209,20 @@
 +static u8
 +peek_old_byte(struct unlzma_ctx *ctx, u32 offs)
 +{
-+      struct unlzma_buffer *bh = ctx->head;
++      struct unlzma_buffer *bh = &ctx->buffers[ctx->n_buffers - 1];
++      int i = ctx->n_buffers;
 +      u32 pos;
 +
++      BUG_ON(!ctx->n_buffers);
 +      pos = ctx->pos - offs;
 +      if (pos >= ctx->dict_size) {
 +              pos = (~pos % ctx->dict_size);
 +      }
 +
 +      while (bh->offset > pos) {
-+              bh = bh->last;
-+              BUG_ON(!bh);
++              bh--;
++              i--;
++              BUG_ON(!i);
 +      }
 +
 +      pos -= bh->offset;
@@ -460,6 +464,7 @@
 +              hdr_buf[i] = rc_read(ctx);
 +      }
 +
++      ctx->n_buffers = 0;
 +      ctx->pos = 0;
 +      get_buffer(ctx);
 +      ctx->active = true;
@@ -554,11 +559,6 @@
 +              unlzma_reset_buf(ctx);
 +              ctx->cancel = false;
 +              ctx->active = false;
-+              while (ctx->head) {
-+                      struct unlzma_buffer *bh = ctx->head;
-+                      ctx->head = bh->last;
-+                      kfree(bh);
-+              }
 +      } while (!kthread_should_stop());
 +      mutex_unlock(&ctx->mutex);
 +      return 0;
@@ -598,6 +598,10 @@
 +              unlzma_cancel(ctx);
 +              kthread_stop(ctx->thread);
 +              ctx->thread = NULL;
++              if (ctx->buffers)
++                      kfree(ctx->buffers);
++              ctx->buffers_max = 0;
++              ctx->buffers = NULL;
 +      }
 +}
 +
@@ -605,10 +609,31 @@
 +unlzma_decompress_setup(struct crypto_pcomp *tfm, void *p, unsigned int len)
 +{
 +      struct unlzma_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
++      struct nlattr *tb[UNLZMA_DECOMP_MAX + 1];
 +      int ret = 0;
 +
 +      if (ctx->thread)
-+              return 0;
++              return -EINVAL;
++
++      if (!p)
++              return -EINVAL;
++
++      ret = nla_parse(tb, UNLZMA_DECOMP_MAX, p, len, NULL);
++      if (!tb[UNLZMA_DECOMP_OUT_BUFFERS])
++              return -EINVAL;
++
++      if (ctx->buffers_max && (ctx->buffers_max <
++          nla_get_u32(tb[UNLZMA_DECOMP_OUT_BUFFERS]))) {
++              kfree(ctx->buffers);
++              ctx->buffers_max = 0;
++              ctx->buffers = NULL;
++      }
++      if (!ctx->buffers) {
++              ctx->buffers_max = nla_get_u32(tb[UNLZMA_DECOMP_OUT_BUFFERS]);
++              ctx->buffers = kzalloc(sizeof(struct unlzma_buffer) * ctx->buffers_max, GFP_KERNEL);
++      }
++      if (!ctx->buffers)
++              return -ENOMEM;
 +
 +      mutex_init(&ctx->mutex);
 +      init_waitqueue_head(&ctx->next_req);
@@ -832,3 +857,18 @@
 +#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
 +
 +#endif
+--- a/include/crypto/compress.h
++++ b/include/crypto/compress.h
+@@ -49,6 +49,12 @@ enum zlib_decomp_params {
+ 
+ #define ZLIB_DECOMP_MAX       (__ZLIB_DECOMP_MAX - 1)
+ 
++enum unlzma_decomp_params {
++      UNLZMA_DECOMP_OUT_BUFFERS = 1, /* naximum number of output buffers */
++      __UNLZMA_DECOMP_MAX,
++};
++#define UNLZMA_DECOMP_MAX     (__UNLZMA_DECOMP_MAX - 1)
++
+ 
+ struct crypto_pcomp {
+       struct crypto_tfm base;