powerpc: Create disable_kernel_{fp,altivec,vsx,spe}()

The enable_kernel_*() functions leave the relevant MSR bits enabled
until we exit the kernel sometime later. Create disable versions
that wrap the kernel use of FP, Altivec VSX or SPE.

While we don't want to disable it normally for performance reasons
(MSR writes are slow), it will be used for a debug boot option that
does this and catches bad uses in other areas of the kernel.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

4 files changed, 13 insertions, 0 deletions

diff --git a/drivers/crypto/vmx/aes.c b/drivers/crypto/vmx/aes.c
index 20539fb..022c7ab 100644
--- a/drivers/crypto/vmx/aes.c
+++ b/drivers/crypto/vmx/aes.c
@@ -86,6 +86,7 @@ static int p8_aes_setkey(struct crypto_tfm *tfm, const u8 *key,
 	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);
+	disable_kernel_vsx();
 	pagefault_enable();
 	preempt_enable();
 
@@ -104,6 +105,7 @@ static void p8_aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
 		pagefault_disable();
 		enable_kernel_vsx();
 		aes_p8_encrypt(src, dst, &ctx->enc_key);
+		disable_kernel_vsx();
 		pagefault_enable();
 		preempt_enable();
 	}
@@ -120,6 +122,7 @@ static void p8_aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
 		pagefault_disable();
 		enable_kernel_vsx();
 		aes_p8_decrypt(src, dst, &ctx->dec_key);
+		disable_kernel_vsx();
 		pagefault_enable();
 		preempt_enable();
 	}
diff --git a/drivers/crypto/vmx/aes_cbc.c b/drivers/crypto/vmx/aes_cbc.c
index 8847b92..1881b3f 100644
--- a/drivers/crypto/vmx/aes_cbc.c
+++ b/drivers/crypto/vmx/aes_cbc.c
@@ -87,6 +87,7 @@ static int p8_aes_cbc_setkey(struct crypto_tfm *tfm, const u8 *key,
 	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);
+	disable_kernel_vsx();
 	pagefault_enable();
 	preempt_enable();
 
@@ -127,6 +128,7 @@ static int p8_aes_cbc_encrypt(struct blkcipher_desc *desc,
 			ret = blkcipher_walk_done(desc, &walk, nbytes);
 		}
 
+		disable_kernel_vsx();
 		pagefault_enable();
 		preempt_enable();
 	}
@@ -167,6 +169,7 @@ static int p8_aes_cbc_decrypt(struct blkcipher_desc *desc,
 			ret = blkcipher_walk_done(desc, &walk, nbytes);
 		}
 
+		disable_kernel_vsx();
 		pagefault_enable();
 		preempt_enable();
 	}
diff --git a/drivers/crypto/vmx/aes_ctr.c b/drivers/crypto/vmx/aes_ctr.c
index 8095866..2d58b18 100644
--- a/drivers/crypto/vmx/aes_ctr.c
+++ b/drivers/crypto/vmx/aes_ctr.c
@@ -83,6 +83,7 @@ static int p8_aes_ctr_setkey(struct crypto_tfm *tfm, const u8 *key,
 	pagefault_disable();
 	enable_kernel_vsx();
 	ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key);
+	disable_kernel_vsx();
 	pagefault_enable();
 
 	ret += crypto_blkcipher_setkey(ctx->fallback, key, keylen);
@@ -101,6 +102,7 @@ static void p8_aes_ctr_final(struct p8_aes_ctr_ctx *ctx,
 	pagefault_disable();
 	enable_kernel_vsx();
 	aes_p8_encrypt(ctrblk, keystream, &ctx->enc_key);
+	disable_kernel_vsx();
 	pagefault_enable();
 
 	crypto_xor(keystream, src, nbytes);
@@ -139,6 +141,7 @@ static int p8_aes_ctr_crypt(struct blkcipher_desc *desc,
 						    AES_BLOCK_SIZE,
 						    &ctx->enc_key,
 						    walk.iv);
+			disable_kernel_vsx();
 			pagefault_enable();
 
 			/* We need to update IV mostly for last bytes/round */
diff --git a/drivers/crypto/vmx/ghash.c b/drivers/crypto/vmx/ghash.c
index 1f4586c..6c999cb0 100644
--- a/drivers/crypto/vmx/ghash.c
+++ b/drivers/crypto/vmx/ghash.c
@@ -120,6 +120,7 @@ static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key,
 	pagefault_disable();
 	enable_kernel_vsx();
 	gcm_init_p8(ctx->htable, (const u64 *) key);
+	disable_kernel_vsx();
 	pagefault_enable();
 	preempt_enable();
 	return crypto_shash_setkey(ctx->fallback, key, keylen);
@@ -150,6 +151,7 @@ static int p8_ghash_update(struct shash_desc *desc,
 			enable_kernel_vsx();
 			gcm_ghash_p8(dctx->shash, ctx->htable,
 				     dctx->buffer, GHASH_DIGEST_SIZE);
+			disable_kernel_vsx();
 			pagefault_enable();
 			preempt_enable();
 			src += GHASH_DIGEST_SIZE - dctx->bytes;
@@ -162,6 +164,7 @@ static int p8_ghash_update(struct shash_desc *desc,
 			pagefault_disable();
 			enable_kernel_vsx();
 			gcm_ghash_p8(dctx->shash, ctx->htable, src, len);
+			disable_kernel_vsx();
 			pagefault_enable();
 			preempt_enable();
 			src += len;
@@ -192,6 +195,7 @@ static int p8_ghash_final(struct shash_desc *desc, u8 *out)
 			enable_kernel_vsx();
 			gcm_ghash_p8(dctx->shash, ctx->htable,
 				     dctx->buffer, GHASH_DIGEST_SIZE);
+			disable_kernel_vsx();
 			pagefault_enable();
 			preempt_enable();
 			dctx->bytes = 0;