CRYPTO: Octeon: always disable preemption when using crypto engine

Always disable preemption on behalf of the drivers when crypto engine
is taken into use. This will simplify the usage.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David S. Miller <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9494/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 3 insertions, 5 deletions

diff --git a/arch/mips/cavium-octeon/crypto/octeon-crypto.c b/arch/mips/cavium-octeon/crypto/octeon-crypto.c
index 7c82ff463b65..f66bd1adc7ff 100644
--- a/arch/mips/cavium-octeon/crypto/octeon-crypto.c
+++ b/arch/mips/cavium-octeon/crypto/octeon-crypto.c
@@ -17,7 +17,7 @@
  * crypto operations in calls to octeon_crypto_enable/disable in order to make
  * sure the state of COP2 isn't corrupted if userspace is also performing
  * hardware crypto operations. Allocate the state parameter on the stack.
- * Preemption must be disabled to prevent context switches.
+ * Returns with preemption disabled.
  *
  * @state: Pointer to state structure to store current COP2 state in.
  *
@@ -28,6 +28,7 @@ unsigned long octeon_crypto_enable(struct octeon_cop2_state *state)
         int status;
         unsigned long flags;
 
+        preempt_disable();
         local_irq_save(flags);
         status = read_c0_status();
         write_c0_status(status | ST0_CU2);
@@ -62,5 +63,6 @@ void octeon_crypto_disable(struct octeon_cop2_state *state,
         else
                 write_c0_status(read_c0_status() & ~ST0_CU2);
         local_irq_restore(flags);
+        preempt_enable();
 }
 EXPORT_SYMBOL_GPL(octeon_crypto_disable);
diff --git a/arch/mips/cavium-octeon/crypto/octeon-md5.c b/arch/mips/cavium-octeon/crypto/octeon-md5.c
index 3dd88450d440..12dccdb38286 100644
--- a/arch/mips/cavium-octeon/crypto/octeon-md5.c
+++ b/arch/mips/cavium-octeon/crypto/octeon-md5.c
@@ -97,7 +97,6 @@ static int octeon_md5_update(struct shash_desc *desc, const u8 *data,
         memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), data,
                avail);
 
-        preempt_disable();
         flags = octeon_crypto_enable(&state);
         octeon_md5_store_hash(mctx);
 
@@ -113,7 +112,6 @@ static int octeon_md5_update(struct shash_desc *desc, const u8 *data,
 
         octeon_md5_read_hash(mctx);
         octeon_crypto_disable(&state, flags);
-        preempt_enable();
 
         memcpy(mctx->block, data, len);
 
@@ -131,7 +129,6 @@ static int octeon_md5_final(struct shash_desc *desc, u8 *out)
 
         *p++ = 0x80;
 
-        preempt_disable();
         flags = octeon_crypto_enable(&state);
         octeon_md5_store_hash(mctx);
 
@@ -149,7 +146,6 @@ static int octeon_md5_final(struct shash_desc *desc, u8 *out)
 
         octeon_md5_read_hash(mctx);
         octeon_crypto_disable(&state, flags);
-        preempt_enable();
 
         memcpy(out, mctx->hash, sizeof(mctx->hash));
         memset(mctx, 0, sizeof(*mctx));