crypto: vmx - Adding enable_kernel_vsx() to access VSX instructions

commit 2d6f0600 upstream.

vmx-crypto driver make use of some VSX instructions which are
only available if VSX is enabled. Running in cases where VSX
are not enabled vmx-crypto fails in a VSX exception.

In order to fix this enable_kernel_vsx() was added to turn on
VSX instructions for vmx-crypto.
Signed-off-by: Leonidas S. Barbosa <leosilva@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/crypto/vmx/aes.c

@@ -80,6 +80,7 @@ static int p8_aes_setkey(struct crypto_tfm *tfm, const u8 *key,
 
     pagefault_disable();
     enable_kernel_altivec();
+    enable_kernel_vsx();
     ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key);
     ret += aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key);
     pagefault_enable();
@@ -97,6 +98,7 @@ static void p8_aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
     } else {
         pagefault_disable();
         enable_kernel_altivec();
+        enable_kernel_vsx();
         aes_p8_encrypt(src, dst, &ctx->enc_key);
         pagefault_enable();
     }
@@ -111,6 +113,7 @@ static void p8_aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
     } else {
         pagefault_disable();
         enable_kernel_altivec();
+        enable_kernel_vsx();
         aes_p8_decrypt(src, dst, &ctx->dec_key);
         pagefault_enable();
     }

drivers/crypto/vmx/aes_cbc.c

@@ -81,6 +81,7 @@ static int p8_aes_cbc_setkey(struct crypto_tfm *tfm, const u8 *key,
 
     pagefault_disable();
     enable_kernel_altivec();
+    enable_kernel_vsx();
     ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key);
     ret += aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key);
     pagefault_enable();
@@ -108,6 +109,7 @@ static int p8_aes_cbc_encrypt(struct blkcipher_desc *desc,
     } else {
         pagefault_disable();
         enable_kernel_altivec();
+        enable_kernel_vsx();
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
         ret = blkcipher_walk_virt(desc, &walk);
@@ -143,6 +145,7 @@ static int p8_aes_cbc_decrypt(struct blkcipher_desc *desc,
     } else {
         pagefault_disable();
         enable_kernel_altivec();
+        enable_kernel_vsx();
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
         ret = blkcipher_walk_virt(desc, &walk);

drivers/crypto/vmx/aes_ctr.c

@@ -79,6 +79,7 @@ static int p8_aes_ctr_setkey(struct crypto_tfm *tfm, const u8 *key,
 
     pagefault_disable();
     enable_kernel_altivec();
+    enable_kernel_vsx();
     ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key);
     pagefault_enable();
 
@@ -97,6 +98,7 @@ static void p8_aes_ctr_final(struct p8_aes_ctr_ctx *ctx,
 
     pagefault_disable();
     enable_kernel_altivec();
+    enable_kernel_vsx();
     aes_p8_encrypt(ctrblk, keystream, &ctx->enc_key);
     pagefault_enable();
 
@@ -127,6 +129,7 @@ static int p8_aes_ctr_crypt(struct blkcipher_desc *desc,
         while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
             pagefault_disable();
             enable_kernel_altivec();
+            enable_kernel_vsx();
             aes_p8_ctr32_encrypt_blocks(walk.src.virt.addr, walk.dst.virt.addr,
                 (nbytes & AES_BLOCK_MASK)/AES_BLOCK_SIZE, &ctx->enc_key, walk.iv);
             pagefault_enable();

drivers/crypto/vmx/ghash.c

@@ -116,6 +116,7 @@ static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key,
 
     pagefault_disable();
     enable_kernel_altivec();
+    enable_kernel_vsx();
     enable_kernel_fp();
     gcm_init_p8(ctx->htable, (const u64 *) key);
     pagefault_enable();
@@ -142,6 +143,7 @@ static int p8_ghash_update(struct shash_desc *desc,
                     GHASH_DIGEST_SIZE - dctx->bytes);
             pagefault_disable();
             enable_kernel_altivec();
+            enable_kernel_vsx();
             enable_kernel_fp();
             gcm_ghash_p8(dctx->shash, ctx->htable, dctx->buffer,
                     GHASH_DIGEST_SIZE);
@@ -154,6 +156,7 @@ static int p8_ghash_update(struct shash_desc *desc,
         if (len) {
             pagefault_disable();
             enable_kernel_altivec();
+            enable_kernel_vsx();
             enable_kernel_fp();
             gcm_ghash_p8(dctx->shash, ctx->htable, src, len);
             pagefault_enable();
@@ -182,6 +185,7 @@ static int p8_ghash_final(struct shash_desc *desc, u8 *out)
                 dctx->buffer[i] = 0;
             pagefault_disable();
             enable_kernel_altivec();
+            enable_kernel_vsx();
             enable_kernel_fp();
             gcm_ghash_p8(dctx->shash, ctx->htable, dctx->buffer,
                     GHASH_DIGEST_SIZE);