[PATCH v10 12/25] crypto: acomp - Add "void *kernel_data" in "struct acomp_req" for kernel users.

[Kanchana P Sridhar]

This commit adds a "void *kernel_data" member in "struct acomp_req":

  @kernel_data:  Private API kernel code data for kernel users

This allows kernel modules such as zswap and zram to input driver data
without interfering with existing usage of acomp_req->base.data.

Since acomp_request_set_params() is the main interface for kernel users
to initialize the acomp_req members, this routine sets
acomp_req->kernel_data to NULL. Kernel users such as zswap will need to
explicitly set acomp_req->kernel_data for interacting with
crypto_acomp_[de]compress(). This usage model will be covered in a
separate patch-series.

Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@xxxxxxxxx>
---
 include/crypto/acompress.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/crypto/acompress.h b/include/crypto/acompress.h
index 9eacb9fa375d7..0312322d2ca03 100644
--- a/include/crypto/acompress.h
+++ b/include/crypto/acompress.h
@@ -79,6 +79,7 @@ struct acomp_req_chain {
  * @dvirt:	Destination virtual address
  * @slen:	Size of the input buffer
  * @dlen:	Size of the output buffer and number of bytes produced
+ * @kernel_data:  Private API kernel code data for kernel users
  * @chain:	Private API code data, do not use
  * @__ctx:	Start of private context data
  */
@@ -95,6 +96,7 @@ struct acomp_req {
 	unsigned int slen;
 	unsigned int dlen;
 
+	void *kernel_data;
 	struct acomp_req_chain chain;
 
 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
@@ -354,6 +356,7 @@ static inline void acomp_request_set_params(struct acomp_req *req,
 	req->dst = dst;
 	req->slen = slen;
 	req->dlen = dlen;
+	req->kernel_data = NULL;
 
 	req->base.flags &= ~(CRYPTO_ACOMP_REQ_SRC_VIRT |
 			     CRYPTO_ACOMP_REQ_SRC_NONDMA |
-- 
2.27.0