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 

1 files changed, 39 insertions, 13 deletions

diff --git a/man/man5/zfs-module-parameters.5 b/man/man5/zfs-module-parameters.5
index a1a586df1..4a3ff1d49 100644
--- a/man/man5/zfs-module-parameters.5
+++ b/man/man5/zfs-module-parameters.5
@@ -2045,6 +2045,45 @@ Use \fB1\fR for yes and \fB0\fR for no (default).
 .sp
 .ne 2
 .na
+\fBzfs_qat_checksum_disable\fR (int)
+.ad
+.RS 12n
+This tunable disables qat hardware acceleration for sha256 checksums. It
+may be set after the zfs modules have been loaded to initialize the qat
+hardware as long as support is compiled in and the qat driver is present.
+.sp
+Use \fB1\fR for yes and \fB0\fR for no (default).
+.RE
+
+.sp
+.ne 2
+.na
+\fBzfs_qat_compress_disable\fR (int)
+.ad
+.RS 12n
+This tunable disables qat hardware acceleration for gzip compression. It
+may be set after the zfs modules have been loaded to initialize the qat
+hardware as long as support is compiled in and the qat driver is present.
+.sp
+Use \fB1\fR for yes and \fB0\fR for no (default).
+.RE
+
+.sp
+.ne 2
+.na
+\fBzfs_qat_encrypt_disable\fR (int)
+.ad
+.RS 12n
+This tunable disables qat hardware acceleration for AES-GCM encryption. It
+may be set after the zfs modules have been loaded to initialize the qat
+hardware as long as support is compiled in and the qat driver is present.
+.sp
+Use \fB1\fR for yes and \fB0\fR for no (default).
+.RE
+
+.sp
+.ne 2
+.na
 \fBzfs_read_chunk_size\fR (long)
 .ad
 .RS 12n
@@ -2961,19 +3000,6 @@ Valid values are \fB1\fR (full), \fB2\fR (dev) and \fB3\fR (none).
 Default value: \fB1\fR.
 .RE
 
-.sp
-.ne 2
-.na
-\fBzfs_qat_disable\fR (int)
-.ad
-.RS 12n
-This tunable disables qat hardware acceleration for gzip compression and.
-AES-GCM encryption. It is available only if qat acceleration is compiled in
-and the qat driver is present.
-.sp
-Use \fB1\fR for yes and \fB0\fR for no (default).
-.RE
-
 .SH ZFS I/O SCHEDULER
 ZFS issues I/O operations to leaf vdevs to satisfy and complete I/Os.
 The I/O scheduler determines when and in what order those operations are