1 files changed, 153 insertions, 47 deletions

diff --git a/drivers/crypto/padlock-aes.c b/drivers/crypto/padlock-aes.c
index bf2917d197a..633ba945e15 100644
--- a/drivers/crypto/padlock-aes.c
+++ b/drivers/crypto/padlock-aes.c
@@ -9,15 +9,32 @@
 
 #include <crypto/algapi.h>
 #include <crypto/aes.h>
+#include <crypto/padlock.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/errno.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
+#include <linux/percpu.h>
+#include <linux/smp.h>
+#include <linux/slab.h>
+#include <asm/cpu_device_id.h>
 #include <asm/byteorder.h>
+#include <asm/processor.h>
 #include <asm/i387.h>
-#include "padlock.h"
+
+/*
+ * Number of data blocks actually fetched for each xcrypt insn.
+ * Processors with prefetch errata will fetch extra blocks.
+ */
+static unsigned int ecb_fetch_blocks = 2;
+#define MAX_ECB_FETCH_BLOCKS (8)
+#define ecb_fetch_bytes (ecb_fetch_blocks * AES_BLOCK_SIZE)
+
+static unsigned int cbc_fetch_blocks = 1;
+#define MAX_CBC_FETCH_BLOCKS (4)
+#define cbc_fetch_bytes (cbc_fetch_blocks * AES_BLOCK_SIZE)
 
 /* Control word. */
 struct cword {
@@ -49,6 +66,8 @@ struct aes_ctx {
 	u32 *D;
 };
 
+static DEFINE_PER_CPU(struct cword *, paes_last_cword);
+
 /* Tells whether the ACE is capable to generate
    the extended key for a given key_len. */
 static inline int
@@ -89,6 +108,7 @@ static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
 	const __le32 *key = (const __le32 *)in_key;
 	u32 *flags = &tfm->crt_flags;
 	struct crypto_aes_ctx gen_aes;
+	int cpu;
 
 	if (key_len % 8) {
 		*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
@@ -118,7 +138,7 @@ static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
 
 	/* Don't generate extended keys if the hardware can do it. */
 	if (aes_hw_extkey_available(key_len))
-		return 0;
+		goto ok;
 
 	ctx->D = ctx->d_data;
 	ctx->cword.encrypt.keygen = 1;
@@ -131,15 +151,34 @@ static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
 
 	memcpy(ctx->E, gen_aes.key_enc, AES_MAX_KEYLENGTH);
 	memcpy(ctx->D, gen_aes.key_dec, AES_MAX_KEYLENGTH);
+
+ok:
+	for_each_online_cpu(cpu)
+		if (&ctx->cword.encrypt == per_cpu(paes_last_cword, cpu) ||
+		    &ctx->cword.decrypt == per_cpu(paes_last_cword, cpu))
+			per_cpu(paes_last_cword, cpu) = NULL;
+
 	return 0;
 }
 
 /* ====== Encryption/decryption routines ====== */
 
 /* These are the real call to PadLock. */
-static inline void padlock_reset_key(void)
+static inline void padlock_reset_key(struct cword *cword)
+{
+	int cpu = raw_smp_processor_id();
+
+	if (cword != per_cpu(paes_last_cword, cpu))
+#ifndef CONFIG_X86_64
+		asm volatile ("pushfl; popfl");
+#else
+		asm volatile ("pushfq; popfq");
+#endif
+}
+
+static inline void padlock_store_cword(struct cword *cword)
 {
-	asm volatile ("pushfl; popfl");
+	per_cpu(paes_last_cword, raw_smp_processor_id()) = cword;
 }
 
 /*
@@ -148,64 +187,111 @@ static inline void padlock_reset_key(void)
  * should be used only inside the irq_ts_save/restore() context
  */
 
-static inline void padlock_xcrypt(const u8 *input, u8 *output, void *key,
-				  void *control_word)
+static inline void rep_xcrypt_ecb(const u8 *input, u8 *output, void *key,
+				  struct cword *control_word, int count)
 {
 	asm volatile (".byte 0xf3,0x0f,0xa7,0xc8"	/* rep xcryptecb */
 		      : "+S"(input), "+D"(output)
-		      : "d"(control_word), "b"(key), "c"(1));
+		      : "d"(control_word), "b"(key), "c"(count));
+}
+
+static inline u8 *rep_xcrypt_cbc(const u8 *input, u8 *output, void *key,
+				 u8 *iv, struct cword *control_word, int count)
+{
+	asm volatile (".byte 0xf3,0x0f,0xa7,0xd0"	/* rep xcryptcbc */
+		      : "+S" (input), "+D" (output), "+a" (iv)
+		      : "d" (control_word), "b" (key), "c" (count));
+	return iv;
+}
+
+static void ecb_crypt_copy(const u8 *in, u8 *out, u32 *key,
+			   struct cword *cword, int count)
+{
+	/*
+	 * Padlock prefetches extra data so we must provide mapped input buffers.
+	 * Assume there are at least 16 bytes of stack already in use.
+	 */
+	u8 buf[AES_BLOCK_SIZE * (MAX_ECB_FETCH_BLOCKS - 1) + PADLOCK_ALIGNMENT - 1];
+	u8 *tmp = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT);
+
+	memcpy(tmp, in, count * AES_BLOCK_SIZE);
+	rep_xcrypt_ecb(tmp, out, key, cword, count);
 }
 
-static void aes_crypt_copy(const u8 *in, u8 *out, u32 *key, struct cword *cword)
+static u8 *cbc_crypt_copy(const u8 *in, u8 *out, u32 *key,
+			   u8 *iv, struct cword *cword, int count)
 {
-	u8 buf[AES_BLOCK_SIZE * 2 + PADLOCK_ALIGNMENT - 1];
+	/*
+	 * Padlock prefetches extra data so we must provide mapped input buffers.
+	 * Assume there are at least 16 bytes of stack already in use.
+	 */
+	u8 buf[AES_BLOCK_SIZE * (MAX_CBC_FETCH_BLOCKS - 1) + PADLOCK_ALIGNMENT - 1];
 	u8 *tmp = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT);
 
-	memcpy(tmp, in, AES_BLOCK_SIZE);
-	padlock_xcrypt(tmp, out, key, cword);
+	memcpy(tmp, in, count * AES_BLOCK_SIZE);
+	return rep_xcrypt_cbc(tmp, out, key, iv, cword, count);
 }
 
-static inline void aes_crypt(const u8 *in, u8 *out, u32 *key,
-			     struct cword *cword)
+static inline void ecb_crypt(const u8 *in, u8 *out, u32 *key,
+			     struct cword *cword, int count)
 {
-	/* padlock_xcrypt requires at least two blocks of data. */
-	if (unlikely(!(((unsigned long)in ^ (PAGE_SIZE - AES_BLOCK_SIZE)) &
-		       (PAGE_SIZE - 1)))) {
-		aes_crypt_copy(in, out, key, cword);
+	/* Padlock in ECB mode fetches at least ecb_fetch_bytes of data.
+	 * We could avoid some copying here but it's probably not worth it.
+	 */
+	if (unlikely(((unsigned long)in & ~PAGE_MASK) + ecb_fetch_bytes > PAGE_SIZE)) {
+		ecb_crypt_copy(in, out, key, cword, count);
 		return;
 	}
 
-	padlock_xcrypt(in, out, key, cword);
+	rep_xcrypt_ecb(in, out, key, cword, count);
+}
+
+static inline u8 *cbc_crypt(const u8 *in, u8 *out, u32 *key,
+			    u8 *iv, struct cword *cword, int count)
+{
+	/* Padlock in CBC mode fetches at least cbc_fetch_bytes of data. */
+	if (unlikely(((unsigned long)in & ~PAGE_MASK) + cbc_fetch_bytes > PAGE_SIZE))
+		return cbc_crypt_copy(in, out, key, iv, cword, count);
+
+	return rep_xcrypt_cbc(in, out, key, iv, cword, count);
 }
 
 static inline void padlock_xcrypt_ecb(const u8 *input, u8 *output, void *key,
 				      void *control_word, u32 count)
 {
-	if (count == 1) {
-		aes_crypt(input, output, key, control_word);
+	u32 initial = count & (ecb_fetch_blocks - 1);
+
+	if (count < ecb_fetch_blocks) {
+		ecb_crypt(input, output, key, control_word, count);
 		return;
 	}
 
-	asm volatile ("test $1, %%cl;"
-		      "je 1f;"
-		      "lea -1(%%ecx), %%eax;"
-		      "mov $1, %%ecx;"
-		      ".byte 0xf3,0x0f,0xa7,0xc8;"	/* rep xcryptecb */
-		      "mov %%eax, %%ecx;"
-		      "1:"
-		      ".byte 0xf3,0x0f,0xa7,0xc8"	/* rep xcryptecb */
+	if (initial)
+		asm volatile (".byte 0xf3,0x0f,0xa7,0xc8"	/* rep xcryptecb */
+			      : "+S"(input), "+D"(output)
+			      : "d"(control_word), "b"(key), "c"(initial));
+
+	asm volatile (".byte 0xf3,0x0f,0xa7,0xc8"	/* rep xcryptecb */
 		      : "+S"(input), "+D"(output)
-		      : "d"(control_word), "b"(key), "c"(count)
-		      : "ax");
+		      : "d"(control_word), "b"(key), "c"(count - initial));
 }
 
 static inline u8 *padlock_xcrypt_cbc(const u8 *input, u8 *output, void *key,
 				     u8 *iv, void *control_word, u32 count)
 {
-	/* rep xcryptcbc */
-	asm volatile (".byte 0xf3,0x0f,0xa7,0xd0"
+	u32 initial = count & (cbc_fetch_blocks - 1);
+
+	if (count < cbc_fetch_blocks)
+		return cbc_crypt(input, output, key, iv, control_word, count);
+
+	if (initial)
+		asm volatile (".byte 0xf3,0x0f,0xa7,0xd0"	/* rep xcryptcbc */
+			      : "+S" (input), "+D" (output), "+a" (iv)
+			      : "d" (control_word), "b" (key), "c" (initial));
+
+	asm volatile (".byte 0xf3,0x0f,0xa7,0xd0"	/* rep xcryptcbc */
 		      : "+S" (input), "+D" (output), "+a" (iv)
-		      : "d" (control_word), "b" (key), "c" (count));
+		      : "d" (control_word), "b" (key), "c" (count-initial));
 	return iv;
 }
 
@@ -213,22 +299,24 @@ static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	struct aes_ctx *ctx = aes_ctx(tfm);
 	int ts_state;
-	padlock_reset_key();
 
+	padlock_reset_key(&ctx->cword.encrypt);
 	ts_state = irq_ts_save();
-	aes_crypt(in, out, ctx->E, &ctx->cword.encrypt);
+	ecb_crypt(in, out, ctx->E, &ctx->cword.encrypt, 1);
 	irq_ts_restore(ts_state);
+	padlock_store_cword(&ctx->cword.encrypt);
 }
 
 static void aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	struct aes_ctx *ctx = aes_ctx(tfm);
 	int ts_state;
-	padlock_reset_key();
 
+	padlock_reset_key(&ctx->cword.encrypt);
 	ts_state = irq_ts_save();
-	aes_crypt(in, out, ctx->D, &ctx->cword.decrypt);
+	ecb_crypt(in, out, ctx->D, &ctx->cword.decrypt, 1);
 	irq_ts_restore(ts_state);
+	padlock_store_cword(&ctx->cword.encrypt);
 }
 
 static struct crypto_alg aes_alg = {
@@ -240,7 +328,6 @@ static struct crypto_alg aes_alg = {
 	.cra_ctxsize		=	sizeof(struct aes_ctx),
 	.cra_alignmask		=	PADLOCK_ALIGNMENT - 1,
 	.cra_module		=	THIS_MODULE,
-	.cra_list		=	LIST_HEAD_INIT(aes_alg.cra_list),
 	.cra_u			=	{
 		.cipher = {
 			.cia_min_keysize	=	AES_MIN_KEY_SIZE,
@@ -261,7 +348,7 @@ static int ecb_aes_encrypt(struct blkcipher_desc *desc,
 	int err;
 	int ts_state;
 
-	padlock_reset_key();
+	padlock_reset_key(&ctx->cword.encrypt);
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
@@ -276,6 +363,8 @@ static int ecb_aes_encrypt(struct blkcipher_desc *desc,
 	}
 	irq_ts_restore(ts_state);
 
+	padlock_store_cword(&ctx->cword.encrypt);
+
 	return err;
 }
 
@@ -288,7 +377,7 @@ static int ecb_aes_decrypt(struct blkcipher_desc *desc,
 	int err;
 	int ts_state;
 
-	padlock_reset_key();
+	padlock_reset_key(&ctx->cword.decrypt);
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
@@ -302,6 +391,9 @@ static int ecb_aes_decrypt(struct blkcipher_desc *desc,
 		err = blkcipher_walk_done(desc, &walk, nbytes);
 	}
 	irq_ts_restore(ts_state);
+
+	padlock_store_cword(&ctx->cword.encrypt);
+
 	return err;
 }
 
@@ -315,7 +407,6 @@ static struct crypto_alg ecb_aes_alg = {
 	.cra_alignmask		=	PADLOCK_ALIGNMENT - 1,
 	.cra_type		=	&crypto_blkcipher_type,
 	.cra_module		=	THIS_MODULE,
-	.cra_list		=	LIST_HEAD_INIT(ecb_aes_alg.cra_list),
 	.cra_u			=	{
 		.blkcipher = {
 			.min_keysize		=	AES_MIN_KEY_SIZE,
@@ -336,7 +427,7 @@ static int cbc_aes_encrypt(struct blkcipher_desc *desc,
 	int err;
 	int ts_state;
 
-	padlock_reset_key();
+	padlock_reset_key(&ctx->cword.encrypt);
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
@@ -353,6 +444,8 @@ static int cbc_aes_encrypt(struct blkcipher_desc *desc,
 	}
 	irq_ts_restore(ts_state);
 
+	padlock_store_cword(&ctx->cword.decrypt);
+
 	return err;
 }
 
@@ -365,7 +458,7 @@ static int cbc_aes_decrypt(struct blkcipher_desc *desc,
 	int err;
 	int ts_state;
 
-	padlock_reset_key();
+	padlock_reset_key(&ctx->cword.encrypt);
 
 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	err = blkcipher_walk_virt(desc, &walk);
@@ -380,6 +473,9 @@ static int cbc_aes_decrypt(struct blkcipher_desc *desc,
 	}
 
 	irq_ts_restore(ts_state);
+
+	padlock_store_cword(&ctx->cword.encrypt);
+
 	return err;
 }
 
@@ -393,7 +489,6 @@ static struct crypto_alg cbc_aes_alg = {
 	.cra_alignmask		=	PADLOCK_ALIGNMENT - 1,
 	.cra_type		=	&crypto_blkcipher_type,
 	.cra_module		=	THIS_MODULE,
-	.cra_list		=	LIST_HEAD_INIT(cbc_aes_alg.cra_list),
 	.cra_u			=	{
 		.blkcipher = {
 			.min_keysize		=	AES_MIN_KEY_SIZE,
@@ -406,14 +501,19 @@ static struct crypto_alg cbc_aes_alg = {
 	}
 };
 
+static struct x86_cpu_id padlock_cpu_id[] = {
+	X86_FEATURE_MATCH(X86_FEATURE_XCRYPT),
+	{}
+};
+MODULE_DEVICE_TABLE(x86cpu, padlock_cpu_id);
+
 static int __init padlock_init(void)
 {
 	int ret;
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
-	if (!cpu_has_xcrypt) {
-		printk(KERN_NOTICE PFX "VIA PadLock not detected.\n");
+	if (!x86_match_cpu(padlock_cpu_id))
 		return -ENODEV;
-	}
 
 	if (!cpu_has_xcrypt_enabled) {
 		printk(KERN_NOTICE PFX "VIA PadLock detected, but not enabled. Hmm, strange...\n");
@@ -431,6 +531,12 @@ static int __init padlock_init(void)
 
 	printk(KERN_NOTICE PFX "Using VIA PadLock ACE for AES algorithm.\n");
 
+	if (c->x86 == 6 && c->x86_model == 15 && c->x86_mask == 2) {
+		ecb_fetch_blocks = MAX_ECB_FETCH_BLOCKS;
+		cbc_fetch_blocks = MAX_CBC_FETCH_BLOCKS;
+		printk(KERN_NOTICE PFX "VIA Nano stepping 2 detected: enabling workaround.\n");
+	}
+
 out:
 	return ret;