mmc: core: Add basic support for inline encryption
authorEric Biggers <ebiggers@google.com>
Tue, 26 Jan 2021 00:14:48 +0000 (16:14 -0800)
committerUlf Hansson <ulf.hansson@linaro.org>
Mon, 1 Feb 2021 11:02:33 +0000 (12:02 +0100)
In preparation for adding CQHCI crypto engine (inline encryption)
support, add the code required to make mmc_core and mmc_block aware of
inline encryption.  Specifically:

- Add a capability flag MMC_CAP2_CRYPTO to struct mmc_host.  Drivers
  will set this if the host and driver support inline encryption.

- Embed a blk_keyslot_manager in struct mmc_host.  Drivers will
  initialize this (as a device-managed resource) if the host and driver
  support inline encryption.  mmc_block registers this keyslot manager
  with the request_queue of any MMC card attached to the host.

- Make mmc_block copy the crypto keyslot and crypto data unit number
  from struct request to struct mmc_request, so that drivers will have
  access to them.

- If the MMC host is reset, reprogram all the keyslots to ensure that
  the software state stays in sync with the hardware state.

Co-developed-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Satya Tangirala <satyat@google.com>
Reviewed-and-tested-by: Peng Zhou <peng.zhou@mediatek.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20210126001456.382989-2-ebiggers@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
drivers/mmc/core/Kconfig
drivers/mmc/core/Makefile
drivers/mmc/core/block.c
drivers/mmc/core/core.c
drivers/mmc/core/crypto.c [new file with mode: 0644]
drivers/mmc/core/crypto.h [new file with mode: 0644]
drivers/mmc/core/host.c
drivers/mmc/core/queue.c
include/linux/mmc/core.h
include/linux/mmc/host.h

index c12fe13e4b1472595b3a68744fc45a83bb750493..ae8b69aee61907e44fc1a3d6ce1956f623f3a2db 100644 (file)
@@ -81,3 +81,11 @@ config MMC_TEST
          This driver is only of interest to those developing or
          testing a host driver. Most people should say N here.
 
+config MMC_CRYPTO
+       bool "MMC Crypto Engine Support"
+       depends on BLK_INLINE_ENCRYPTION
+       help
+         Enable Crypto Engine Support in MMC.
+         Enabling this makes it possible for the kernel to use the crypto
+         capabilities of the MMC device (if present) to perform crypto
+         operations on data being transferred to/from the device.
index 95ffe008ebdf8e088379ca8491078df594d0c9c2..6a907736cd7a515cf80e616114b0e6f924d63773 100644 (file)
@@ -18,3 +18,4 @@ obj-$(CONFIG_MMC_BLOCK)               += mmc_block.o
 mmc_block-objs                 := block.o queue.o
 obj-$(CONFIG_MMC_TEST)         += mmc_test.o
 obj-$(CONFIG_SDIO_UART)                += sdio_uart.o
+mmc_core-$(CONFIG_MMC_CRYPTO)  += crypto.o
index 42e27a2982180efe570f1ea658c6dfc57ccf4222..b877f62df3660d1e6f3ebe1bf2dc837eb3fa8715 100644 (file)
@@ -51,6 +51,7 @@
 #include "block.h"
 #include "core.h"
 #include "card.h"
+#include "crypto.h"
 #include "host.h"
 #include "bus.h"
 #include "mmc_ops.h"
@@ -1247,6 +1248,8 @@ static void mmc_blk_data_prep(struct mmc_queue *mq, struct mmc_queue_req *mqrq,
 
        memset(brq, 0, sizeof(struct mmc_blk_request));
 
+       mmc_crypto_prepare_req(mqrq);
+
        brq->mrq.data = &brq->data;
        brq->mrq.tag = req->tag;
 
index 49d9117550afef412695a3f4556de83f1f821578..1136b859ddd86d5397abbd48b9c462cab0e80eaa 100644 (file)
@@ -37,6 +37,7 @@
 
 #include "core.h"
 #include "card.h"
+#include "crypto.h"
 #include "bus.h"
 #include "host.h"
 #include "sdio_bus.h"
@@ -992,6 +993,8 @@ void mmc_set_initial_state(struct mmc_host *host)
                host->ops->hs400_enhanced_strobe(host, &host->ios);
 
        mmc_set_ios(host);
+
+       mmc_crypto_set_initial_state(host);
 }
 
 /**
diff --git a/drivers/mmc/core/crypto.c b/drivers/mmc/core/crypto.c
new file mode 100644 (file)
index 0000000..419a368
--- /dev/null
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MMC crypto engine (inline encryption) support
+ *
+ * Copyright 2020 Google LLC
+ */
+
+#include <linux/blk-crypto.h>
+#include <linux/mmc/host.h>
+
+#include "core.h"
+#include "crypto.h"
+#include "queue.h"
+
+void mmc_crypto_set_initial_state(struct mmc_host *host)
+{
+       /* Reset might clear all keys, so reprogram all the keys. */
+       if (host->caps2 & MMC_CAP2_CRYPTO)
+               blk_ksm_reprogram_all_keys(&host->ksm);
+}
+
+void mmc_crypto_setup_queue(struct request_queue *q, struct mmc_host *host)
+{
+       if (host->caps2 & MMC_CAP2_CRYPTO)
+               blk_ksm_register(&host->ksm, q);
+}
+EXPORT_SYMBOL_GPL(mmc_crypto_setup_queue);
+
+void mmc_crypto_prepare_req(struct mmc_queue_req *mqrq)
+{
+       struct request *req = mmc_queue_req_to_req(mqrq);
+       struct mmc_request *mrq = &mqrq->brq.mrq;
+
+       if (!req->crypt_keyslot)
+               return;
+
+       mrq->crypto_enabled = true;
+       mrq->crypto_key_slot = blk_ksm_get_slot_idx(req->crypt_keyslot);
+
+       /*
+        * For now we assume that all MMC drivers set max_dun_bytes_supported=4,
+        * which is the limit for CQHCI crypto.  So all DUNs should be 32-bit.
+        */
+       WARN_ON_ONCE(req->crypt_ctx->bc_dun[0] > U32_MAX);
+
+       mrq->data_unit_num = req->crypt_ctx->bc_dun[0];
+}
+EXPORT_SYMBOL_GPL(mmc_crypto_prepare_req);
diff --git a/drivers/mmc/core/crypto.h b/drivers/mmc/core/crypto.h
new file mode 100644 (file)
index 0000000..fbe9a52
--- /dev/null
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * MMC crypto engine (inline encryption) support
+ *
+ * Copyright 2020 Google LLC
+ */
+
+#ifndef _MMC_CORE_CRYPTO_H
+#define _MMC_CORE_CRYPTO_H
+
+struct mmc_host;
+struct mmc_queue_req;
+struct request_queue;
+
+#ifdef CONFIG_MMC_CRYPTO
+
+void mmc_crypto_set_initial_state(struct mmc_host *host);
+
+void mmc_crypto_setup_queue(struct request_queue *q, struct mmc_host *host);
+
+void mmc_crypto_prepare_req(struct mmc_queue_req *mqrq);
+
+#else /* CONFIG_MMC_CRYPTO */
+
+static inline void mmc_crypto_set_initial_state(struct mmc_host *host)
+{
+}
+
+static inline void mmc_crypto_setup_queue(struct request_queue *q,
+                                         struct mmc_host *host)
+{
+}
+
+static inline void mmc_crypto_prepare_req(struct mmc_queue_req *mqrq)
+{
+}
+
+#endif /* !CONFIG_MMC_CRYPTO */
+
+#endif /* _MMC_CORE_CRYPTO_H */
index 74e853bb694821bf3a0d4fab3e59adf134295eb1..9b89a91b6b476d325e73672fd324498ccaf171b6 100644 (file)
@@ -25,6 +25,7 @@
 #include <linux/mmc/slot-gpio.h>
 
 #include "core.h"
+#include "crypto.h"
 #include "host.h"
 #include "slot-gpio.h"
 #include "pwrseq.h"
index 002426e3cf76c9d2f0fec4c35f757a7153717710..33e7e65b6ddea86512f5bc7d96696eed38b0fe34 100644 (file)
@@ -19,6 +19,7 @@
 #include "block.h"
 #include "core.h"
 #include "card.h"
+#include "crypto.h"
 #include "host.h"
 
 #define MMC_DMA_MAP_MERGE_SEGMENTS     512
@@ -407,6 +408,8 @@ static void mmc_setup_queue(struct mmc_queue *mq, struct mmc_card *card)
        mutex_init(&mq->complete_lock);
 
        init_waitqueue_head(&mq->wait);
+
+       mmc_crypto_setup_queue(mq->queue, host);
 }
 
 static inline bool mmc_merge_capable(struct mmc_host *host)
index 29aa507116261f109bfbe36305d630bbbc622ef9..ab19245e994511d8359c3f695eee4a889450976c 100644 (file)
@@ -162,6 +162,12 @@ struct mmc_request {
        bool                    cap_cmd_during_tfr;
 
        int                     tag;
+
+#ifdef CONFIG_MMC_CRYPTO
+       bool                    crypto_enabled;
+       int                     crypto_key_slot;
+       u32                     data_unit_num;
+#endif
 };
 
 struct mmc_card;
index 8cf686d98a68f3ab7ae5c07186394a7ca852c377..927ba75666176ac9914983724d1cea829ba7d226 100644 (file)
@@ -15,6 +15,7 @@
 #include <linux/mmc/card.h>
 #include <linux/mmc/pm.h>
 #include <linux/dma-direction.h>
+#include <linux/keyslot-manager.h>
 
 struct mmc_ios {
        unsigned int    clock;                  /* clock rate */
@@ -395,6 +396,11 @@ struct mmc_host {
 #define MMC_CAP2_CQE_DCMD      (1 << 24)       /* CQE can issue a direct command */
 #define MMC_CAP2_AVOID_3_3V    (1 << 25)       /* Host must negotiate down from 3.3V */
 #define MMC_CAP2_MERGE_CAPABLE (1 << 26)       /* Host can merge a segment over the segment size */
+#ifdef CONFIG_MMC_CRYPTO
+#define MMC_CAP2_CRYPTO                (1 << 27)       /* Host supports inline encryption */
+#else
+#define MMC_CAP2_CRYPTO                0
+#endif
 
        int                     fixed_drv_type; /* fixed driver type for non-removable media */
 
@@ -489,6 +495,11 @@ struct mmc_host {
        bool                    cqe_enabled;
        bool                    cqe_on;
 
+       /* Inline encryption support */
+#ifdef CONFIG_MMC_CRYPTO
+       struct blk_keyslot_manager ksm;
+#endif
+
        /* Host Software Queue support */
        bool                    hsq_enabled;