crypto: aes-ni - Do not sleep when using the FPU

Because AES-NI instructions will touch XMM state, corresponding code
must be enclosed within kernel_fpu_begin/end, which used
preempt_disable/enable. So sleep should be prevented between
kernel_fpu_begin/end.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index 4e66339..c580c5e 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -198,6 +198,7 @@
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
+	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
@@ -221,6 +222,7 @@
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
+	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
@@ -266,6 +268,7 @@
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
+	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
@@ -289,6 +292,7 @@
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
+	desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {