Merge branch 'zcrypt-no-alloc'

Harald Freudenberger says:

====================
This series of patches has the goal to open up a do-not-allocate
memory path from the callers of the pkey in-kernel api down to
the crypto cards and back.

The asynch in-kernel cipher implementations (and the s390 PAES
cipher implementations are one of them) may be called in a
context where memory allocations which trigger IO is not acceptable.

So this patch series reworks the AP bus code, the zcrypt layer,
the pkey layer and the pkey handlers to respect this situation
by processing a new parameter xflags (execution hints flags).
There is a flag PKEY_XFLAG_NOMEMALLOC which tells the code to
not allocate memory which may lead to IO operations.

To reach this goal, the actual code changes have been differed.
The zcrypt misc functions which need memory for cprb build
use a pre allocated memory pool for this purpose. The findcard()
functions have one temp memory area preallocated and protected
with a mutex. Some smaller data is not allocated any more but went
to the stack instead. The AP bus also uses a pre-allocated
memory pool for building AP message requests.

Note that the PAES implementation still needs to get reworked
to run the protected key derivation in a real asynchronous way.
However, this rework of AP bus, zcrypt and pkey is the base work
required before reconsidering the PAES implementation.

The patch series starts bottom (AP bus) and goes up the call
chain (PKEY). At any time in the patch stack it should compile.
For easier review I tried to have one logic code change by
each patch and thus keep the patches "small".
====================

Link: https://lore.kernel.org/r/20250424133619.16495-1-freude@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

1 files changed, 167 insertions, 319 deletions

diff --git a/drivers/s390/crypto/zcrypt_ccamisc.c b/drivers/s390/crypto/zcrypt_ccamisc.c
index 43a27cb3db84..b975a3728c23 100644
--- a/drivers/s390/crypto/zcrypt_ccamisc.c
+++ b/drivers/s390/crypto/zcrypt_ccamisc.c
@@ -11,6 +11,7 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/init.h>
+#include <linux/mempool.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/random.h>
@@ -29,16 +30,31 @@
 /* Size of vardata block used for some of the cca requests/replies */
 #define VARDATASIZE 4096
 
-struct cca_info_list_entry {
-	struct list_head list;
-	u16 cardnr;
-	u16 domain;
-	struct cca_info info;
-};
+/*
+ * Cprb memory pool held for urgent cases where no memory
+ * can be allocated via kmalloc. This pool is only used
+ * when alloc_and_prep_cprbmem() is called with the xflag
+ * ZCRYPT_XFLAG_NOMEMALLOC. The cprb memory needs to hold
+ * space for request AND reply!
+ */
+#define CPRB_MEMPOOL_ITEM_SIZE (16 * 1024)
+static mempool_t *cprb_mempool;
 
-/* a list with cca_info_list_entry entries */
-static LIST_HEAD(cca_info_list);
-static DEFINE_SPINLOCK(cca_info_list_lock);
+/*
+ * This is a pre-allocated memory for the device status array
+ * used within the findcard() functions. It is currently
+ * 128 * 128 * 4 bytes = 64 KB big. Usage of this memory is
+ * controlled via dev_status_mem_mutex. Needs adaption if more
+ * than 128 cards or domains to be are supported.
+ */
+#define ZCRYPT_DEV_STATUS_CARD_MAX 128
+#define ZCRYPT_DEV_STATUS_QUEUE_MAX 128
+#define ZCRYPT_DEV_STATUS_ENTRIES (ZCRYPT_DEV_STATUS_CARD_MAX * \
+				   ZCRYPT_DEV_STATUS_QUEUE_MAX)
+#define ZCRYPT_DEV_STATUS_EXT_SIZE (ZCRYPT_DEV_STATUS_ENTRIES * \
+		sizeof(struct zcrypt_device_status_ext))
+static void *dev_status_mem;
+static DEFINE_MUTEX(dev_status_mem_mutex);
 
 /*
  * Simple check if the token is a valid CCA secure AES data key
@@ -219,19 +235,27 @@ EXPORT_SYMBOL(cca_check_sececckeytoken);
 static int alloc_and_prep_cprbmem(size_t paramblen,
 				  u8 **p_cprb_mem,
 				  struct CPRBX **p_req_cprb,
-				  struct CPRBX **p_rep_cprb)
+				  struct CPRBX **p_rep_cprb,
+				  u32 xflags)
 {
-	u8 *cprbmem;
+	u8 *cprbmem = NULL;
 	size_t cprbplusparamblen = sizeof(struct CPRBX) + paramblen;
+	size_t len = 2 * cprbplusparamblen;
 	struct CPRBX *preqcblk, *prepcblk;
 
 	/*
 	 * allocate consecutive memory for request CPRB, request param
 	 * block, reply CPRB and reply param block
 	 */
-	cprbmem = kcalloc(2, cprbplusparamblen, GFP_KERNEL);
+	if (xflags & ZCRYPT_XFLAG_NOMEMALLOC) {
+		if (len <= CPRB_MEMPOOL_ITEM_SIZE)
+			cprbmem = mempool_alloc_preallocated(cprb_mempool);
+	} else {
+		cprbmem = kmalloc(len, GFP_KERNEL);
+	}
 	if (!cprbmem)
 		return -ENOMEM;
+	memset(cprbmem, 0, len);
 
 	preqcblk = (struct CPRBX *)cprbmem;
 	prepcblk = (struct CPRBX *)(cprbmem + cprbplusparamblen);
@@ -261,11 +285,15 @@ static int alloc_and_prep_cprbmem(size_t paramblen,
  * with zeros before freeing (useful if there was some
  * clear key material in there).
  */
-static void free_cprbmem(void *mem, size_t paramblen, int scrub)
+static void free_cprbmem(void *mem, size_t paramblen, bool scrub, u32 xflags)
 {
-	if (scrub)
+	if (mem && scrub)
 		memzero_explicit(mem, 2 * (sizeof(struct CPRBX) + paramblen));
-	kfree(mem);
+
+	if (xflags & ZCRYPT_XFLAG_NOMEMALLOC)
+		mempool_free(mem, cprb_mempool);
+	else
+		kfree(mem);
 }
 
 /*
@@ -290,7 +318,7 @@ static inline void prep_xcrb(struct ica_xcRB *pxcrb,
  * Generate (random) CCA AES DATA secure key.
  */
 int cca_genseckey(u16 cardnr, u16 domain,
-		  u32 keybitsize, u8 *seckey)
+		  u32 keybitsize, u8 *seckey, u32 xflags)
 {
 	int i, rc, keysize;
 	int seckeysize;
@@ -332,7 +360,8 @@ int cca_genseckey(u16 cardnr, u16 domain,
 	} __packed * prepparm;
 
 	/* get already prepared memory for 2 cprbs with param block each */
-	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem,
+				    &preqcblk, &prepcblk, xflags);
 	if (rc)
 		return rc;
 
@@ -379,7 +408,7 @@ int cca_genseckey(u16 cardnr, u16 domain,
 	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
 
 	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
-	rc = zcrypt_send_cprb(&xcrb);
+	rc = zcrypt_send_cprb(&xcrb, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s zcrypt_send_cprb (cardnr=%d domain=%d) failed, errno %d\n",
 			       __func__, (int)cardnr, (int)domain, rc);
@@ -424,7 +453,7 @@ int cca_genseckey(u16 cardnr, u16 domain,
 	memcpy(seckey, prepparm->lv3.keyblock.tok, SECKEYBLOBSIZE);
 
 out:
-	free_cprbmem(mem, PARMBSIZE, 0);
+	free_cprbmem(mem, PARMBSIZE, false, xflags);
 	return rc;
 }
 EXPORT_SYMBOL(cca_genseckey);
@@ -433,7 +462,7 @@ EXPORT_SYMBOL(cca_genseckey);
  * Generate an CCA AES DATA secure key with given key value.
  */
 int cca_clr2seckey(u16 cardnr, u16 domain, u32 keybitsize,
-		   const u8 *clrkey, u8 *seckey)
+		   const u8 *clrkey, u8 *seckey, u32 xflags)
 {
 	int rc, keysize, seckeysize;
 	u8 *mem, *ptr;
@@ -473,7 +502,8 @@ int cca_clr2seckey(u16 cardnr, u16 domain, u32 keybitsize,
 	} __packed * prepparm;
 
 	/* get already prepared memory for 2 cprbs with param block each */
-	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem,
+				    &preqcblk, &prepcblk, xflags);
 	if (rc)
 		return rc;
 
@@ -517,7 +547,7 @@ int cca_clr2seckey(u16 cardnr, u16 domain, u32 keybitsize,
 	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
 
 	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
-	rc = zcrypt_send_cprb(&xcrb);
+	rc = zcrypt_send_cprb(&xcrb, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s zcrypt_send_cprb (cardnr=%d domain=%d) failed, rc=%d\n",
 			       __func__, (int)cardnr, (int)domain, rc);
@@ -563,7 +593,7 @@ int cca_clr2seckey(u16 cardnr, u16 domain, u32 keybitsize,
 		memcpy(seckey, prepparm->lv3.keyblock.tok, SECKEYBLOBSIZE);
 
 out:
-	free_cprbmem(mem, PARMBSIZE, 1);
+	free_cprbmem(mem, PARMBSIZE, true, xflags);
 	return rc;
 }
 EXPORT_SYMBOL(cca_clr2seckey);
@@ -573,7 +603,7 @@ EXPORT_SYMBOL(cca_clr2seckey);
  */
 int cca_sec2protkey(u16 cardnr, u16 domain,
 		    const u8 *seckey, u8 *protkey, u32 *protkeylen,
-		    u32 *protkeytype)
+		    u32 *protkeytype, u32 xflags)
 {
 	int rc;
 	u8 *mem, *ptr;
@@ -619,7 +649,8 @@ int cca_sec2protkey(u16 cardnr, u16 domain,
 	} __packed * prepparm;
 
 	/* get already prepared memory for 2 cprbs with param block each */
-	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem,
+				    &preqcblk, &prepcblk, xflags);
 	if (rc)
 		return rc;
 
@@ -644,7 +675,7 @@ int cca_sec2protkey(u16 cardnr, u16 domain,
 	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
 
 	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
-	rc = zcrypt_send_cprb(&xcrb);
+	rc = zcrypt_send_cprb(&xcrb, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s zcrypt_send_cprb (cardnr=%d domain=%d) failed, rc=%d\n",
 			       __func__, (int)cardnr, (int)domain, rc);
@@ -712,7 +743,7 @@ int cca_sec2protkey(u16 cardnr, u16 domain,
 		*protkeylen = prepparm->lv3.ckb.len;
 
 out:
-	free_cprbmem(mem, PARMBSIZE, 0);
+	free_cprbmem(mem, PARMBSIZE, true, xflags);
 	return rc;
 }
 EXPORT_SYMBOL(cca_sec2protkey);
@@ -737,7 +768,7 @@ static const u8 aes_cipher_key_skeleton[] = {
  * Generate (random) CCA AES CIPHER secure key.
  */
 int cca_gencipherkey(u16 cardnr, u16 domain, u32 keybitsize, u32 keygenflags,
-		     u8 *keybuf, u32 *keybufsize)
+		     u8 *keybuf, u32 *keybufsize, u32 xflags)
 {
 	int rc;
 	u8 *mem, *ptr;
@@ -813,7 +844,8 @@ int cca_gencipherkey(u16 cardnr, u16 domain, u32 keybitsize, u32 keygenflags,
 	struct cipherkeytoken *t;
 
 	/* get already prepared memory for 2 cprbs with param block each */
-	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem,
+				    &preqcblk, &prepcblk, xflags);
 	if (rc)
 		return rc;
 
@@ -872,7 +904,7 @@ int cca_gencipherkey(u16 cardnr, u16 domain, u32 keybitsize, u32 keygenflags,
 	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
 
 	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
-	rc = zcrypt_send_cprb(&xcrb);
+	rc = zcrypt_send_cprb(&xcrb, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s zcrypt_send_cprb (cardnr=%d domain=%d) failed, rc=%d\n",
 			       __func__, (int)cardnr, (int)domain, rc);
@@ -923,7 +955,7 @@ int cca_gencipherkey(u16 cardnr, u16 domain, u32 keybitsize, u32 keygenflags,
 	*keybufsize = t->len;
 
 out:
-	free_cprbmem(mem, PARMBSIZE, 0);
+	free_cprbmem(mem, PARMBSIZE, false, xflags);
 	return rc;
 }
 EXPORT_SYMBOL(cca_gencipherkey);
@@ -938,7 +970,8 @@ static int _ip_cprb_helper(u16 cardnr, u16 domain,
 			   const u8 *clr_key_value,
 			   int clr_key_bit_size,
 			   u8 *key_token,
-			   int *key_token_size)
+			   int *key_token_size,
+			   u32 xflags)
 {
 	int rc, n;
 	u8 *mem, *ptr;
@@ -989,7 +1022,8 @@ static int _ip_cprb_helper(u16 cardnr, u16 domain,
 	int complete = strncmp(rule_array_2, "COMPLETE", 8) ? 0 : 1;
 
 	/* get already prepared memory for 2 cprbs with param block each */
-	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem,
+				    &preqcblk, &prepcblk, xflags);
 	if (rc)
 		return rc;
 
@@ -1038,7 +1072,7 @@ static int _ip_cprb_helper(u16 cardnr, u16 domain,
 	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
 
 	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
-	rc = zcrypt_send_cprb(&xcrb);
+	rc = zcrypt_send_cprb(&xcrb, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s zcrypt_send_cprb (cardnr=%d domain=%d) failed, rc=%d\n",
 			       __func__, (int)cardnr, (int)domain, rc);
@@ -1077,7 +1111,7 @@ static int _ip_cprb_helper(u16 cardnr, u16 domain,
 	*key_token_size = t->len;
 
 out:
-	free_cprbmem(mem, PARMBSIZE, 0);
+	free_cprbmem(mem, PARMBSIZE, false, xflags);
 	return rc;
 }
 
@@ -1085,23 +1119,31 @@ out:
  * Build CCA AES CIPHER secure key with a given clear key value.
  */
 int cca_clr2cipherkey(u16 card, u16 dom, u32 keybitsize, u32 keygenflags,
-		      const u8 *clrkey, u8 *keybuf, u32 *keybufsize)
+		      const u8 *clrkey, u8 *keybuf, u32 *keybufsize, u32 xflags)
 {
 	int rc;
-	u8 *token;
+	void *mem;
 	int tokensize;
-	u8 exorbuf[32];
+	u8 *token, exorbuf[32];
 	struct cipherkeytoken *t;
 
 	/* fill exorbuf with random data */
 	get_random_bytes(exorbuf, sizeof(exorbuf));
 
-	/* allocate space for the key token to build */
-	token = kmalloc(MAXCCAVLSCTOKENSIZE, GFP_KERNEL);
-	if (!token)
+	/*
+	 * Allocate space for the key token to build.
+	 * Also we only need up to MAXCCAVLSCTOKENSIZE bytes for this
+	 * we use the already existing cprb mempool to solve this
+	 * short term memory requirement.
+	 */
+	mem = (xflags & ZCRYPT_XFLAG_NOMEMALLOC) ?
+		mempool_alloc_preallocated(cprb_mempool) :
+		mempool_alloc(cprb_mempool, GFP_KERNEL);
+	if (!mem)
 		return -ENOMEM;
 
 	/* prepare the token with the key skeleton */
+	token = (u8 *)mem;
 	tokensize = SIZEOF_SKELETON;
 	memcpy(token, aes_cipher_key_skeleton, tokensize);
 
@@ -1120,28 +1162,28 @@ int cca_clr2cipherkey(u16 card, u16 dom, u32 keybitsize, u32 keygenflags,
 	 * 4/4 COMPLETE the secure cipher key import
 	 */
 	rc = _ip_cprb_helper(card, dom, "AES     ", "FIRST   ", "MIN3PART",
-			     exorbuf, keybitsize, token, &tokensize);
+			     exorbuf, keybitsize, token, &tokensize, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s clear key import 1/4 with CSNBKPI2 failed, rc=%d\n",
 			       __func__, rc);
 		goto out;
 	}
 	rc = _ip_cprb_helper(card, dom, "AES     ", "ADD-PART", NULL,
-			     clrkey, keybitsize, token, &tokensize);
+			     clrkey, keybitsize, token, &tokensize, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s clear key import 2/4 with CSNBKPI2 failed, rc=%d\n",
 			       __func__, rc);
 		goto out;
 	}
 	rc = _ip_cprb_helper(card, dom, "AES     ", "ADD-PART", NULL,
-			     exorbuf, keybitsize, token, &tokensize);
+			     exorbuf, keybitsize, token, &tokensize, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s clear key import 3/4 with CSNBKPI2 failed, rc=%d\n",
 			       __func__, rc);
 		goto out;
 	}
 	rc = _ip_cprb_helper(card, dom, "AES     ", "COMPLETE", NULL,
-			     NULL, keybitsize, token, &tokensize);
+			     NULL, keybitsize, token, &tokensize, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s clear key import 4/4 with CSNBKPI2 failed, rc=%d\n",
 			       __func__, rc);
@@ -1158,7 +1200,7 @@ int cca_clr2cipherkey(u16 card, u16 dom, u32 keybitsize, u32 keygenflags,
 	*keybufsize = tokensize;
 
 out:
-	kfree(token);
+	mempool_free(mem, cprb_mempool);
 	return rc;
 }
 EXPORT_SYMBOL(cca_clr2cipherkey);
@@ -1167,7 +1209,8 @@ EXPORT_SYMBOL(cca_clr2cipherkey);
  * Derive proteced key from CCA AES cipher secure key.
  */
 int cca_cipher2protkey(u16 cardnr, u16 domain, const u8 *ckey,
-		       u8 *protkey, u32 *protkeylen, u32 *protkeytype)
+		       u8 *protkey, u32 *protkeylen, u32 *protkeytype,
+		       u32 xflags)
 {
 	int rc;
 	u8 *mem, *ptr;
@@ -1219,7 +1262,8 @@ int cca_cipher2protkey(u16 cardnr, u16 domain, const u8 *ckey,
 	int keytoklen = ((struct cipherkeytoken *)ckey)->len;
 
 	/* get already prepared memory for 2 cprbs with param block each */
-	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem,
+				    &preqcblk, &prepcblk, xflags);
 	if (rc)
 		return rc;
 
@@ -1249,7 +1293,7 @@ int cca_cipher2protkey(u16 cardnr, u16 domain, const u8 *ckey,
 	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
 
 	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
-	rc = zcrypt_send_cprb(&xcrb);
+	rc = zcrypt_send_cprb(&xcrb, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s zcrypt_send_cprb (cardnr=%d domain=%d) failed, rc=%d\n",
 			       __func__, (int)cardnr, (int)domain, rc);
@@ -1323,7 +1367,7 @@ int cca_cipher2protkey(u16 cardnr, u16 domain, const u8 *ckey,
 		*protkeylen = prepparm->vud.ckb.keylen;
 
 out:
-	free_cprbmem(mem, PARMBSIZE, 0);
+	free_cprbmem(mem, PARMBSIZE, true, xflags);
 	return rc;
 }
 EXPORT_SYMBOL(cca_cipher2protkey);
@@ -1332,7 +1376,7 @@ EXPORT_SYMBOL(cca_cipher2protkey);
  * Derive protected key from CCA ECC secure private key.
  */
 int cca_ecc2protkey(u16 cardnr, u16 domain, const u8 *key,
-		    u8 *protkey, u32 *protkeylen, u32 *protkeytype)
+		    u8 *protkey, u32 *protkeylen, u32 *protkeytype, u32 xflags)
 {
 	int rc;
 	u8 *mem, *ptr;
@@ -1382,7 +1426,8 @@ int cca_ecc2protkey(u16 cardnr, u16 domain, const u8 *key,
 	int keylen = ((struct eccprivkeytoken *)key)->len;
 
 	/* get already prepared memory for 2 cprbs with param block each */
-	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem,
+				    &preqcblk, &prepcblk, xflags);
 	if (rc)
 		return rc;
 
@@ -1412,7 +1457,7 @@ int cca_ecc2protkey(u16 cardnr, u16 domain, const u8 *key,
 	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
 
 	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
-	rc = zcrypt_send_cprb(&xcrb);
+	rc = zcrypt_send_cprb(&xcrb, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s zcrypt_send_cprb (cardnr=%d domain=%d) failed, rc=%d\n",
 			       __func__, (int)cardnr, (int)domain, rc);
@@ -1470,7 +1515,7 @@ int cca_ecc2protkey(u16 cardnr, u16 domain, const u8 *key,
 		*protkeytype = PKEY_KEYTYPE_ECC;
 
 out:
-	free_cprbmem(mem, PARMBSIZE, 0);
+	free_cprbmem(mem, PARMBSIZE, true, xflags);
 	return rc;
 }
 EXPORT_SYMBOL(cca_ecc2protkey);
@@ -1481,7 +1526,8 @@ EXPORT_SYMBOL(cca_ecc2protkey);
 int cca_query_crypto_facility(u16 cardnr, u16 domain,
 			      const char *keyword,
 			      u8 *rarray, size_t *rarraylen,
-			      u8 *varray, size_t *varraylen)
+			      u8 *varray, size_t *varraylen,
+			      u32 xflags)
 {
 	int rc;
 	u16 len;
@@ -1505,7 +1551,8 @@ int cca_query_crypto_facility(u16 cardnr, u16 domain,
 	} __packed * prepparm;
 
 	/* get already prepared memory for 2 cprbs with param block each */
-	rc = alloc_and_prep_cprbmem(parmbsize, &mem, &preqcblk, &prepcblk);
+	rc = alloc_and_prep_cprbmem(parmbsize, &mem,
+				    &preqcblk, &prepcblk, xflags);
 	if (rc)
 		return rc;
 
@@ -1526,7 +1573,7 @@ int cca_query_crypto_facility(u16 cardnr, u16 domain,
 	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
 
 	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
-	rc = zcrypt_send_cprb(&xcrb);
+	rc = zcrypt_send_cprb(&xcrb, xflags);
 	if (rc) {
 		ZCRYPT_DBF_ERR("%s zcrypt_send_cprb (cardnr=%d domain=%d) failed, rc=%d\n",
 			       __func__, (int)cardnr, (int)domain, rc);
@@ -1573,94 +1620,21 @@ int cca_query_crypto_facility(u16 cardnr, u16 domain,
 	}
 
 out:
-	free_cprbmem(mem, parmbsize, 0);
+	free_cprbmem(mem, parmbsize, false, xflags);
 	return rc;
 }
 EXPORT_SYMBOL(cca_query_crypto_facility);
 
-static int cca_info_cache_fetch(u16 cardnr, u16 domain, struct cca_info *ci)
-{
-	int rc = -ENOENT;
-	struct cca_info_list_entry *ptr;
-
-	spin_lock_bh(&cca_info_list_lock);
-	list_for_each_entry(ptr, &cca_info_list, list) {
-		if (ptr->cardnr == cardnr && ptr->domain == domain) {
-			memcpy(ci, &ptr->info, sizeof(*ci));
-			rc = 0;
-			break;
-		}
-	}
-	spin_unlock_bh(&cca_info_list_lock);
-
-	return rc;
-}
-
-static void cca_info_cache_update(u16 cardnr, u16 domain,
-				  const struct cca_info *ci)
-{
-	int found = 0;
-	struct cca_info_list_entry *ptr;
-
-	spin_lock_bh(&cca_info_list_lock);
-	list_for_each_entry(ptr, &cca_info_list, list) {
-		if (ptr->cardnr == cardnr &&
-		    ptr->domain == domain) {
-			memcpy(&ptr->info, ci, sizeof(*ci));
-			found = 1;
-			break;
-		}
-	}
-	if (!found) {
-		ptr = kmalloc(sizeof(*ptr), GFP_ATOMIC);
-		if (!ptr) {
-			spin_unlock_bh(&cca_info_list_lock);
-			return;
-		}
-		ptr->cardnr = cardnr;
-		ptr->domain = domain;
-		memcpy(&ptr->info, ci, sizeof(*ci));
-		list_add(&ptr->list, &cca_info_list);
-	}
-	spin_unlock_bh(&cca_info_list_lock);
-}
-
-static void cca_info_cache_scrub(u16 cardnr, u16 domain)
-{
-	struct cca_info_list_entry *ptr;
-
-	spin_lock_bh(&cca_info_list_lock);
-	list_for_each_entry(ptr, &cca_info_list, list) {
-		if (ptr->cardnr == cardnr &&
-		    ptr->domain == domain) {
-			list_del(&ptr->list);
-			kfree(ptr);
-			break;
-		}
-	}
-	spin_unlock_bh(&cca_info_list_lock);
-}
-
-static void __exit mkvp_cache_free(void)
-{
-	struct cca_info_list_entry *ptr, *pnext;
-
-	spin_lock_bh(&cca_info_list_lock);
-	list_for_each_entry_safe(ptr, pnext, &cca_info_list, list) {
-		list_del(&ptr->list);
-		kfree(ptr);
-	}
-	spin_unlock_bh(&cca_info_list_lock);
-}
-
 /*
- * Fetch cca_info values via query_crypto_facility from adapter.
+ * Fetch cca_info values about a CCA queue via
+ * query_crypto_facility from adapter.
  */
-static int fetch_cca_info(u16 cardnr, u16 domain, struct cca_info *ci)
+int cca_get_info(u16 cardnr, u16 domain, struct cca_info *ci, u32 xflags)
 {
+	void *mem;
 	int rc, found = 0;
 	size_t rlen, vlen;
-	u8 *rarray, *varray, *pg;
+	u8 *rarray, *varray;
 	struct zcrypt_device_status_ext devstat;
 
 	memset(ci, 0, sizeof(*ci));
@@ -1671,17 +1645,22 @@ static int fetch_cca_info(u16 cardnr, u16 domain, struct cca_info *ci)
 		return rc;
 	ci->hwtype = devstat.hwtype;
 
-	/* prep page for rule array and var array use */
-	pg = (u8 *)__get_free_page(GFP_KERNEL);
-	if (!pg)
+	/*
+	 * Prep memory for rule array and var array use.
+	 * Use the cprb mempool for this.
+	 */
+	mem = (xflags & ZCRYPT_XFLAG_NOMEMALLOC) ?
+		mempool_alloc_preallocated(cprb_mempool) :
+		mempool_alloc(cprb_mempool, GFP_KERNEL);
+	if (!mem)
 		return -ENOMEM;
-	rarray = pg;
-	varray = pg + PAGE_SIZE / 2;
+	rarray = (u8 *)mem;
+	varray = (u8 *)mem + PAGE_SIZE / 2;
 	rlen = vlen = PAGE_SIZE / 2;
 
 	/* QF for this card/domain */
 	rc = cca_query_crypto_facility(cardnr, domain, "STATICSA",
-				       rarray, &rlen, varray, &vlen);
+				       rarray, &rlen, varray, &vlen, xflags);
 	if (rc == 0 && rlen >= 10 * 8 && vlen >= 204) {
 		memcpy(ci->serial, rarray, 8);
 		ci->new_asym_mk_state = (char)rarray[4 * 8];
@@ -1708,7 +1687,7 @@ static int fetch_cca_info(u16 cardnr, u16 domain, struct cca_info *ci)
 		goto out;
 	rlen = vlen = PAGE_SIZE / 2;
 	rc = cca_query_crypto_facility(cardnr, domain, "STATICSB",
-				       rarray, &rlen, varray, &vlen);
+				       rarray, &rlen, varray, &vlen, xflags);
 	if (rc == 0 && rlen >= 13 * 8 && vlen >= 240) {
 		ci->new_apka_mk_state = (char)rarray[10 * 8];
 		ci->cur_apka_mk_state = (char)rarray[11 * 8];
@@ -1723,177 +1702,32 @@ static int fetch_cca_info(u16 cardnr, u16 domain, struct cca_info *ci)
 	}
 
 out:
-	free_page((unsigned long)pg);
+	mempool_free(mem, cprb_mempool);
 	return found == 2 ? 0 : -ENOENT;
 }
-
-/*
- * Fetch cca information about a CCA queue.
- */
-int cca_get_info(u16 card, u16 dom, struct cca_info *ci, int verify)
-{
-	int rc;
-
-	rc = cca_info_cache_fetch(card, dom, ci);
-	if (rc || verify) {
-		rc = fetch_cca_info(card, dom, ci);
-		if (rc == 0)
-			cca_info_cache_update(card, dom, ci);
-	}
-
-	return rc;
-}
 EXPORT_SYMBOL(cca_get_info);
 
-/*
- * Search for a matching crypto card based on the
- * Master Key Verification Pattern given.
- */
-static int findcard(u64 mkvp, u16 *pcardnr, u16 *pdomain,
-		    int verify, int minhwtype)
-{
-	struct zcrypt_device_status_ext *device_status;
-	u16 card, dom;
-	struct cca_info ci;
-	int i, rc, oi = -1;
-
-	/* mkvp must not be zero, minhwtype needs to be >= 0 */
-	if (mkvp == 0 || minhwtype < 0)
-		return -EINVAL;
-
-	/* fetch status of all crypto cards */
-	device_status = kvcalloc(MAX_ZDEV_ENTRIES_EXT,
-				 sizeof(struct zcrypt_device_status_ext),
-				 GFP_KERNEL);
-	if (!device_status)
-		return -ENOMEM;
-	zcrypt_device_status_mask_ext(device_status);
-
-	/* walk through all crypto cards */
-	for (i = 0; i < MAX_ZDEV_ENTRIES_EXT; i++) {
-		card = AP_QID_CARD(device_status[i].qid);
-		dom = AP_QID_QUEUE(device_status[i].qid);
-		if (device_status[i].online &&
-		    device_status[i].functions & 0x04) {
-			/* enabled CCA card, check current mkvp from cache */
-			if (cca_info_cache_fetch(card, dom, &ci) == 0 &&
-			    ci.hwtype >= minhwtype &&
-			    ci.cur_aes_mk_state == '2' &&
-			    ci.cur_aes_mkvp == mkvp) {
-				if (!verify)
-					break;
-				/* verify: refresh card info */
-				if (fetch_cca_info(card, dom, &ci) == 0) {
-					cca_info_cache_update(card, dom, &ci);
-					if (ci.hwtype >= minhwtype &&
-					    ci.cur_aes_mk_state == '2' &&
-					    ci.cur_aes_mkvp == mkvp)
-						break;
-				}
-			}
-		} else {
-			/* Card is offline and/or not a CCA card. */
-			/* del mkvp entry from cache if it exists */
-			cca_info_cache_scrub(card, dom);
-		}
-	}
-	if (i >= MAX_ZDEV_ENTRIES_EXT) {
-		/* nothing found, so this time without cache */
-		for (i = 0; i < MAX_ZDEV_ENTRIES_EXT; i++) {
-			if (!(device_status[i].online &&
-			      device_status[i].functions & 0x04))
-				continue;
-			card = AP_QID_CARD(device_status[i].qid);
-			dom = AP_QID_QUEUE(device_status[i].qid);
-			/* fresh fetch mkvp from adapter */
-			if (fetch_cca_info(card, dom, &ci) == 0) {
-				cca_info_cache_update(card, dom, &ci);
-				if (ci.hwtype >= minhwtype &&
-				    ci.cur_aes_mk_state == '2' &&
-				    ci.cur_aes_mkvp == mkvp)
-					break;
-				if (ci.hwtype >= minhwtype &&
-				    ci.old_aes_mk_state == '2' &&
-				    ci.old_aes_mkvp == mkvp &&
-				    oi < 0)
-					oi = i;
-			}
-		}
-		if (i >= MAX_ZDEV_ENTRIES_EXT && oi >= 0) {
-			/* old mkvp matched, use this card then */
-			card = AP_QID_CARD(device_status[oi].qid);
-			dom = AP_QID_QUEUE(device_status[oi].qid);
-		}
-	}
-	if (i < MAX_ZDEV_ENTRIES_EXT || oi >= 0) {
-		if (pcardnr)
-			*pcardnr = card;
-		if (pdomain)
-			*pdomain = dom;
-		rc = (i < MAX_ZDEV_ENTRIES_EXT ? 0 : 1);
-	} else {
-		rc = -ENODEV;
-	}
-
-	kvfree(device_status);
-	return rc;
-}
-
-/*
- * Search for a matching crypto card based on the Master Key
- * Verification Pattern provided inside a secure key token.
- */
-int cca_findcard(const u8 *key, u16 *pcardnr, u16 *pdomain, int verify)
-{
-	u64 mkvp;
-	int minhwtype = 0;
-	const struct keytoken_header *hdr = (struct keytoken_header *)key;
-
-	if (hdr->type != TOKTYPE_CCA_INTERNAL)
-		return -EINVAL;
-
-	switch (hdr->version) {
-	case TOKVER_CCA_AES:
-		mkvp = ((struct secaeskeytoken *)key)->mkvp;
-		break;
-	case TOKVER_CCA_VLSC:
-		mkvp = ((struct cipherkeytoken *)key)->mkvp0;
-		minhwtype = AP_DEVICE_TYPE_CEX6;
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	return findcard(mkvp, pcardnr, pdomain, verify, minhwtype);
-}
-EXPORT_SYMBOL(cca_findcard);
-
-int cca_findcard2(u32 **apqns, u32 *nr_apqns, u16 cardnr, u16 domain,
+int cca_findcard2(u32 *apqns, u32 *nr_apqns, u16 cardnr, u16 domain,
 		  int minhwtype, int mktype, u64 cur_mkvp, u64 old_mkvp,
-		  int verify)
+		  u32 xflags)
 {
 	struct zcrypt_device_status_ext *device_status;
-	u32 *_apqns = NULL, _nr_apqns = 0;
-	int i, card, dom, curmatch, oldmatch, rc = 0;
+	int i, card, dom, curmatch, oldmatch;
 	struct cca_info ci;
+	u32 _nr_apqns = 0;
 
-	/* fetch status of all crypto cards */
-	device_status = kvcalloc(MAX_ZDEV_ENTRIES_EXT,
-				 sizeof(struct zcrypt_device_status_ext),
-				 GFP_KERNEL);
-	if (!device_status)
-		return -ENOMEM;
-	zcrypt_device_status_mask_ext(device_status);
+	/* occupy the device status memory */
+	mutex_lock(&dev_status_mem_mutex);
+	memset(dev_status_mem, 0, ZCRYPT_DEV_STATUS_EXT_SIZE);
+	device_status = (struct zcrypt_device_status_ext *)dev_status_mem;
 
-	/* allocate 1k space for up to 256 apqns */
-	_apqns = kmalloc_array(256, sizeof(u32), GFP_KERNEL);
-	if (!_apqns) {
-		kvfree(device_status);
-		return -ENOMEM;
-	}
+	/* fetch crypto device status into this struct */
+	zcrypt_device_status_mask_ext(device_status,
+				      ZCRYPT_DEV_STATUS_CARD_MAX,
+				      ZCRYPT_DEV_STATUS_QUEUE_MAX);
 
 	/* walk through all the crypto apqnss */
-	for (i = 0; i < MAX_ZDEV_ENTRIES_EXT; i++) {
+	for (i = 0; i < ZCRYPT_DEV_STATUS_ENTRIES; i++) {
 		card = AP_QID_CARD(device_status[i].qid);
 		dom = AP_QID_QUEUE(device_status[i].qid);
 		/* check online state */
@@ -1909,7 +1743,7 @@ int cca_findcard2(u32 **apqns, u32 *nr_apqns, u16 cardnr, u16 domain,
 		if (domain != 0xFFFF && dom != domain)
 			continue;
 		/* get cca info on this apqn */
-		if (cca_get_info(card, dom, &ci, verify))
+		if (cca_get_info(card, dom, &ci, xflags))
 			continue;
 		/* current master key needs to be valid */
 		if (mktype == AES_MK_SET && ci.cur_aes_mk_state != '2')
@@ -1939,27 +1773,41 @@ int cca_findcard2(u32 **apqns, u32 *nr_apqns, u16 cardnr, u16 domain,
 				continue;
 		}
 		/* apqn passed all filtering criterons, add to the array */
-		if (_nr_apqns < 256)
-			_apqns[_nr_apqns++] = (((u16)card) << 16) | ((u16)dom);
+		if (_nr_apqns < *nr_apqns)
+			apqns[_nr_apqns++] = (((u16)card) << 16) | ((u16)dom);
 	}
 
-	/* nothing found ? */
-	if (!_nr_apqns) {
-		kfree(_apqns);
-		rc = -ENODEV;
-	} else {
-		/* no re-allocation, simple return the _apqns array */
-		*apqns = _apqns;
-		*nr_apqns = _nr_apqns;
-		rc = 0;
-	}
+	*nr_apqns = _nr_apqns;
 
-	kvfree(device_status);
-	return rc;
+	/* release the device status memory */
+	mutex_unlock(&dev_status_mem_mutex);
+
+	return _nr_apqns ? 0 : -ENODEV;
 }
 EXPORT_SYMBOL(cca_findcard2);
 
-void __exit zcrypt_ccamisc_exit(void)
+int __init zcrypt_ccamisc_init(void)
+{
+	/* Pre-allocate a small memory pool for cca cprbs. */
+	cprb_mempool = mempool_create_kmalloc_pool(zcrypt_mempool_threshold,
+						   CPRB_MEMPOOL_ITEM_SIZE);
+	if (!cprb_mempool)
+		return -ENOMEM;
+
+	/* Pre-allocate one crypto status card struct used in findcard() */
+	dev_status_mem = kvmalloc(ZCRYPT_DEV_STATUS_EXT_SIZE, GFP_KERNEL);
+	if (!dev_status_mem) {
+		mempool_destroy(cprb_mempool);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+void zcrypt_ccamisc_exit(void)
 {
-	mkvp_cache_free();
+	mutex_lock(&dev_status_mem_mutex);
+	kvfree(dev_status_mem);
+	mutex_unlock(&dev_status_mem_mutex);
+	mempool_destroy(cprb_mempool);
 }