Code improvement and bug fixes for QAT support

1. Support QAT when ZFS is root file-system:
   When ZFS module is loaded before QAT started, the QAT can
   be started again in post-process, e.g.:
   echo 0 > /sys/module/zfs/parameters/zfs_qat_compress_disable
   echo 0 > /sys/module/zfs/parameters/zfs_qat_encrypt_disable
   echo 0 > /sys/module/zfs/parameters/zfs_qat_checksum_disable
2. Verify alder checksum of the de-compress result
3. Allocate Digest, IV and AAD buffer in physical contiguous
   memory by QAT_PHYS_CONTIG_ALLOC.
4. Update the documentation for zfs_qat_compress_disable,
   zfs_qat_checksum_disable, zfs_qat_encrypt_disable.

Reviewed-by: Tom Caputi <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Weigang Li <[email protected]>
Signed-off-by: Chengfeix Zhu <[email protected]>
Closes #8323 
Closes #8610 

4 files changed, 143 insertions, 38 deletions

diff --git a/module/zfs/qat.c b/module/zfs/qat.c
index 0a4f9c72a..a6f024cb4 100644
--- a/module/zfs/qat.c
+++ b/module/zfs/qat.c
@@ -66,18 +66,6 @@ qat_mem_free_contig(void **pp_mem_addr)
 int
 qat_init(void)
 {
-	int ret;
-
-	ret = qat_dc_init();
-	if (ret != 0)
-		return (ret);
-
-	ret = qat_crypt_init();
-	if (ret != 0) {
-		qat_dc_fini();
-		return (ret);
-	}
-
 	qat_ksp = kstat_create("zfs", 0, "qat", "misc",
 	    KSTAT_TYPE_NAMED, sizeof (qat_stats) / sizeof (kstat_named_t),
 	    KSTAT_FLAG_VIRTUAL);
@@ -86,6 +74,19 @@ qat_init(void)
 		kstat_install(qat_ksp);
 	}
 
+	/*
+	 * Just set the disable flag when qat init failed, qat can be
+	 * turned on again in post-process after zfs module is loaded, e.g.:
+	 * echo 0 > /sys/module/zfs/parameters/zfs_qat_compress_disable
+	 */
+	if (qat_dc_init() != 0)
+		zfs_qat_compress_disable = 1;
+
+	if (qat_cy_init() != 0) {
+		zfs_qat_checksum_disable = 1;
+		zfs_qat_encrypt_disable = 1;
+	}
+
 	return (0);
 }
 
@@ -97,7 +98,7 @@ qat_fini(void)
 		qat_ksp = NULL;
 	}
 
-	qat_crypt_fini();
+	qat_cy_fini();
 	qat_dc_fini();
 }
 
diff --git a/module/zfs/qat.h b/module/zfs/qat.h
index b2cd5a9c1..9014c0314 100644
--- a/module/zfs/qat.h
+++ b/module/zfs/qat.h
@@ -147,6 +147,9 @@ typedef struct qat_stats {
 	QAT_STAT_INCR(stat, 1)
 
 extern qat_stats_t qat_stats;
+extern int zfs_qat_compress_disable;
+extern int zfs_qat_checksum_disable;
+extern int zfs_qat_encrypt_disable;
 
 /* inlined for performance */
 static inline struct page *
@@ -167,8 +170,8 @@ void qat_mem_free_contig(void **pp_mem_addr);
 
 extern int qat_dc_init(void);
 extern void qat_dc_fini(void);
-extern int qat_crypt_init(void);
-extern void qat_crypt_fini(void);
+extern int qat_cy_init(void);
+extern void qat_cy_fini(void);
 extern int qat_init(void);
 extern void qat_fini(void);
 
diff --git a/module/zfs/qat_compress.c b/module/zfs/qat_compress.c
index 8c1410c9e..1c5c0a4e7 100644
--- a/module/zfs/qat_compress.c
+++ b/module/zfs/qat_compress.c
@@ -24,7 +24,9 @@
 #include <linux/vmalloc.h>
 #include <linux/pagemap.h>
 #include <linux/completion.h>
+#include <linux/mod_compat.h>
 #include <sys/zfs_context.h>
+#include <sys/byteorder.h>
 #include <sys/zio.h>
 #include "qat.h"
 
@@ -111,6 +113,9 @@ qat_dc_init(void)
 	Cpa32U buff_meta_size = 0;
 	CpaDcSessionSetupData sd = {0};
 
+	if (qat_dc_init_done)
+		return (0);
+
 	status = cpaDcGetNumInstances(&num_inst);
 	if (status != CPA_STATUS_SUCCESS)
 		return (-1);
@@ -252,6 +257,7 @@ qat_compress_impl(qat_compress_dir_t dir, char *src, int src_len,
 	Cpa32U num_add_buf = (add_len >> PAGE_SHIFT) + 2;
 	Cpa32U bytes_left;
 	Cpa32U dst_pages = 0;
+	Cpa32U adler32 = 0;
 	char *data;
 	struct page *page;
 	struct page **in_pages = NULL;
@@ -468,6 +474,12 @@ qat_compress_impl(qat_compress_dir_t dir, char *src, int src_len,
 			goto fail;
 		}
 
+		/* verify adler checksum */
+		adler32 = *(Cpa32U *)(src + dc_results.consumed + ZLIB_HEAD_SZ);
+		if (adler32 != BSWAP_32(dc_results.checksum)) {
+			status = CPA_STATUS_FAIL;
+			goto fail;
+		}
 		*c_len = dc_results.produced;
 		QAT_STAT_INCR(decomp_total_out_bytes, *c_len);
 	}
@@ -534,7 +546,30 @@ qat_compress(qat_compress_dir_t dir, char *src, int src_len,
 	return (ret);
 }
 
-module_param(zfs_qat_compress_disable, int, 0644);
-MODULE_PARM_DESC(zfs_qat_compress_disable, "Disable QAT compression");
+static int
+param_set_qat_compress(const char *val, struct kernel_param *kp)
+{
+	int ret;
+	int *pvalue = kp->arg;
+	ret = param_set_int(val, kp);
+	if (ret)
+		return (ret);
+	/*
+	 * zfs_qat_compress_disable = 0: enable qat compress
+	 * try to initialize qat instance if it has not been done
+	 */
+	if (*pvalue == 0 && !qat_dc_init_done) {
+		ret = qat_dc_init();
+		if (ret != 0) {
+			zfs_qat_compress_disable = 1;
+			return (ret);
+		}
+	}
+	return (ret);
+}
+
+module_param_call(zfs_qat_compress_disable, param_set_qat_compress,
+    param_get_int, &zfs_qat_compress_disable, 0644);
+MODULE_PARM_DESC(zfs_qat_compress_disable, "Enable/Disable QAT compression");
 
 #endif
diff --git a/module/zfs/qat_crypt.c b/module/zfs/qat_crypt.c
index 5a5113e68..34c19b582 100644
--- a/module/zfs/qat_crypt.c
+++ b/module/zfs/qat_crypt.c
@@ -31,6 +31,7 @@
 #include <linux/vmalloc.h>
 #include <linux/pagemap.h>
 #include <linux/completion.h>
+#include <linux/mod_compat.h>
 #include <sys/zfs_context.h>
 #include <sys/zio_crypt.h>
 #include "lac/cpa_cy_im.h"
@@ -50,7 +51,7 @@
 static Cpa32U inst_num = 0;
 static Cpa16U num_inst = 0;
 static CpaInstanceHandle cy_inst_handles[QAT_CRYPT_MAX_INSTANCES];
-static boolean_t qat_crypt_init_done = B_FALSE;
+static boolean_t qat_cy_init_done = B_FALSE;
 int zfs_qat_encrypt_disable = 0;
 int zfs_qat_checksum_disable = 0;
 
@@ -76,7 +77,7 @@ boolean_t
 qat_crypt_use_accel(size_t s_len)
 {
 	return (!zfs_qat_encrypt_disable &&
-	    qat_crypt_init_done &&
+	    qat_cy_init_done &&
 	    s_len >= QAT_MIN_BUF_SIZE &&
 	    s_len <= QAT_MAX_BUF_SIZE);
 }
@@ -85,26 +86,29 @@ boolean_t
 qat_checksum_use_accel(size_t s_len)
 {
 	return (!zfs_qat_checksum_disable &&
-	    qat_crypt_init_done &&
+	    qat_cy_init_done &&
 	    s_len >= QAT_MIN_BUF_SIZE &&
 	    s_len <= QAT_MAX_BUF_SIZE);
 }
 
 void
-qat_crypt_clean(void)
+qat_cy_clean(void)
 {
 	for (Cpa16U i = 0; i < num_inst; i++)
 		cpaCyStopInstance(cy_inst_handles[i]);
 
 	num_inst = 0;
-	qat_crypt_init_done = B_FALSE;
+	qat_cy_init_done = B_FALSE;
 }
 
 int
-qat_crypt_init(void)
+qat_cy_init(void)
 {
 	CpaStatus status = CPA_STATUS_FAIL;
 
+	if (qat_cy_init_done)
+		return (0);
+
 	status = cpaCyGetNumInstances(&num_inst);
 	if (status != CPA_STATUS_SUCCESS)
 		return (-1);
@@ -131,21 +135,21 @@ qat_crypt_init(void)
 			goto error;
 	}
 
-	qat_crypt_init_done = B_TRUE;
+	qat_cy_init_done = B_TRUE;
 	return (0);
 
 error:
-	qat_crypt_clean();
+	qat_cy_clean();
 	return (-1);
 }
 
 void
-qat_crypt_fini(void)
+qat_cy_fini(void)
 {
-	if (!qat_crypt_init_done)
+	if (!qat_cy_init_done)
 		return;
 
-	qat_crypt_clean();
+	qat_cy_clean();
 }
 
 static CpaStatus
@@ -351,6 +355,21 @@ qat_crypt(qat_encrypt_dir_t dir, uint8_t *src_buf, uint8_t *dst_buf,
 	    nr_bufs * sizeof (CpaFlatBuffer));
 	if (status != CPA_STATUS_SUCCESS)
 		goto fail;
+	status = QAT_PHYS_CONTIG_ALLOC(&op_data.pDigestResult,
+	    ZIO_DATA_MAC_LEN);
+	if (status != CPA_STATUS_SUCCESS)
+		goto fail;
+	status = QAT_PHYS_CONTIG_ALLOC(&op_data.pIv,
+	    ZIO_DATA_IV_LEN);
+	if (status != CPA_STATUS_SUCCESS)
+		goto fail;
+	if (aad_len > 0) {
+		status = QAT_PHYS_CONTIG_ALLOC(&op_data.pAdditionalAuthData,
+		    aad_len);
+		if (status != CPA_STATUS_SUCCESS)
+			goto fail;
+		bcopy(aad_buf, op_data.pAdditionalAuthData, aad_len);
+	}
 
 	bytes_left = enc_len;
 	data = src_buf;
@@ -389,18 +408,13 @@ qat_crypt(qat_encrypt_dir_t dir, uint8_t *src_buf, uint8_t *dst_buf,
 
 	op_data.sessionCtx = cy_session_ctx;
 	op_data.packetType = CPA_CY_SYM_PACKET_TYPE_FULL;
-	op_data.pIv = NULL; /* set this later as the J0 block */
-	op_data.ivLenInBytes = 0;
 	op_data.cryptoStartSrcOffsetInBytes = 0;
 	op_data.messageLenToCipherInBytes = 0;
 	op_data.hashStartSrcOffsetInBytes = 0;
 	op_data.messageLenToHashInBytes = 0;
-	op_data.pDigestResult = 0;
 	op_data.messageLenToCipherInBytes = enc_len;
 	op_data.ivLenInBytes = ZIO_DATA_IV_LEN;
-	op_data.pDigestResult = digest_buf;
-	op_data.pAdditionalAuthData = aad_buf;
-	op_data.pIv = iv_buf;
+	bcopy(iv_buf, op_data.pIv, ZIO_DATA_IV_LEN);
 
 	cb.verify_result = CPA_FALSE;
 	init_completion(&cb.complete);
@@ -420,6 +434,8 @@ qat_crypt(qat_encrypt_dir_t dir, uint8_t *src_buf, uint8_t *dst_buf,
 		goto fail;
 	}
 
+	/* save digest result to digest_buf */
+	bcopy(op_data.pDigestResult, digest_buf, ZIO_DATA_MAC_LEN);
 	if (dir == QAT_ENCRYPT)
 		QAT_STAT_INCR(encrypt_total_out_bytes, enc_len);
 	else
@@ -435,6 +451,10 @@ fail:
 		kunmap(out_pages[i]);
 
 	cpaCySymRemoveSession(cy_inst_handle, cy_session_ctx);
+	if (aad_len > 0)
+		QAT_PHYS_CONTIG_FREE(op_data.pAdditionalAuthData);
+	QAT_PHYS_CONTIG_FREE(op_data.pIv);
+	QAT_PHYS_CONTIG_FREE(op_data.pDigestResult);
 	QAT_PHYS_CONTIG_FREE(src_buffer_list.pPrivateMetaData);
 	QAT_PHYS_CONTIG_FREE(dst_buffer_list.pPrivateMetaData);
 	QAT_PHYS_CONTIG_FREE(cy_session_ctx);
@@ -557,10 +577,56 @@ fail:
 	return (status);
 }
 
-module_param(zfs_qat_encrypt_disable, int, 0644);
-MODULE_PARM_DESC(zfs_qat_encrypt_disable, "Disable QAT encryption");
+static int
+param_set_qat_encrypt(const char *val, struct kernel_param *kp)
+{
+	int ret;
+	int *pvalue = kp->arg;
+	ret = param_set_int(val, kp);
+	if (ret)
+		return (ret);
+	/*
+	 * zfs_qat_encrypt_disable = 0: enable qat encrypt
+	 * try to initialize qat instance if it has not been done
+	 */
+	if (*pvalue == 0 && !qat_cy_init_done) {
+		ret = qat_cy_init();
+		if (ret != 0) {
+			zfs_qat_encrypt_disable = 1;
+			return (ret);
+		}
+	}
+	return (ret);
+}
+
+static int
+param_set_qat_checksum(const char *val, struct kernel_param *kp)
+{
+	int ret;
+	int *pvalue = kp->arg;
+	ret = param_set_int(val, kp);
+	if (ret)
+		return (ret);
+	/*
+	 * set_checksum_param_ops = 0: enable qat checksum
+	 * try to initialize qat instance if it has not been done
+	 */
+	if (*pvalue == 0 && !qat_cy_init_done) {
+		ret = qat_cy_init();
+		if (ret != 0) {
+			zfs_qat_checksum_disable = 1;
+			return (ret);
+		}
+	}
+	return (ret);
+}
+
+module_param_call(zfs_qat_encrypt_disable, param_set_qat_encrypt,
+    param_get_int, &zfs_qat_encrypt_disable, 0644);
+MODULE_PARM_DESC(zfs_qat_encrypt_disable, "Enable/Disable QAT encryption");
 
-module_param(zfs_qat_checksum_disable, int, 0644);
-MODULE_PARM_DESC(zfs_qat_checksum_disable, "Disable QAT checksumming");
+module_param_call(zfs_qat_checksum_disable, param_set_qat_checksum,
+    param_get_int, &zfs_qat_checksum_disable, 0644);
+MODULE_PARM_DESC(zfs_qat_checksum_disable, "Enable/Disable QAT checksumming");
 
 #endif