scsi: ufs: qcom: Convert to use UFSHCD_QUIRK_CUSTOM_CRYPTO_PROFILE

By default the UFS core is responsible for initializing the
blk_crypto_profile, but Qualcomm platforms have their own way of
programming and evicting crypto keys.  So currently
ufs_hba_variant_ops::program_key is used to redirect control flow from
ufshcd_program_key().  This has worked until now, but it's a bit of a hack,
given that the key (and algorithm ID etc.) ends up being converted from
blk_crypto_key => ufs_crypto_cfg_entry => SCM call parameters, where the
intermediate ufs_crypto_cfg_entry step is unnecessary.  Taking a similar
approach with the upcoming wrapped key support, the implementation of which
is similarly platform-specific, would require adding four new methods to
ufs_hba_variant_ops, changing program_key to take the struct
blk_crypto_key, and adding a new UFSHCD_CAP_* flag to indicate support for
wrapped keys.

This patch takes a different approach.  It changes ufs-qcom to use the
existing UFSHCD_QUIRK_CUSTOM_CRYPTO_PROFILE which was recently added for
ufs-exynos.  This allows it to override the full blk_crypto_profile,
eliminating the need for the existing ufs_hba_variant_ops::program_key and
the hooks that would have been needed for wrapped key support.  It does
require a bit of duplicated code to read the crypto capability registers,
but it's worth the simplification in design with ufs-qcom and ufs-exynos
now using the same method to customize the crypto profile, and it makes it
much easier to add wrapped key support.

Tested-by: Bartosz Golaszewski <[email protected]> # sm8650
Signed-off-by: Eric Biggers <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Martin K. Petersen <[email protected]>

Author: ebiggers

drivers/ufs/host/ufs-qcom.c

@@ -112,11 +112,18 @@ static inline void ufs_qcom_ice_enable(struct ufs_qcom_host *host)
 		qcom_ice_enable(host->ice);
 }
 
+static const struct blk_crypto_ll_ops ufs_qcom_crypto_ops; /* forward decl */
+
 static int ufs_qcom_ice_init(struct ufs_qcom_host *host)
 {
 	struct ufs_hba *hba = host->hba;
+	struct blk_crypto_profile *profile = &hba->crypto_profile;
 	struct device *dev = hba->dev;
 	struct qcom_ice *ice;
+	union ufs_crypto_capabilities caps;
+	union ufs_crypto_cap_entry cap;
+	int err;
+	int i;
 
 	ice = of_qcom_ice_get(dev);
 	if (ice == ERR_PTR(-EOPNOTSUPP)) {
@@ -128,8 +135,38 @@ static int ufs_qcom_ice_init(struct ufs_qcom_host *host)
 		return PTR_ERR_OR_ZERO(ice);
 
 	host->ice = ice;
-	hba->caps |= UFSHCD_CAP_CRYPTO;
 
+	/* Initialize the blk_crypto_profile */
+
+	caps.reg_val = cpu_to_le32(ufshcd_readl(hba, REG_UFS_CCAP));
+
+	/* The number of keyslots supported is (CFGC+1) */
+	err = devm_blk_crypto_profile_init(dev, profile, caps.config_count + 1);
+	if (err)
+		return err;
+
+	profile->ll_ops = ufs_qcom_crypto_ops;
+	profile->max_dun_bytes_supported = 8;
+	profile->dev = dev;
+
+	/*
+	 * Currently this driver only supports AES-256-XTS.  All known versions
+	 * of ICE support it, but to be safe make sure it is really declared in
+	 * the crypto capability registers.  The crypto capability registers
+	 * also give the supported data unit size(s).
+	 */
+	for (i = 0; i < caps.num_crypto_cap; i++) {
+		cap.reg_val = cpu_to_le32(ufshcd_readl(hba,
+						       REG_UFS_CRYPTOCAP +
+						       i * sizeof(__le32)));
+		if (cap.algorithm_id == UFS_CRYPTO_ALG_AES_XTS &&
+		    cap.key_size == UFS_CRYPTO_KEY_SIZE_256)
+			profile->modes_supported[BLK_ENCRYPTION_MODE_AES_256_XTS] |=
+				cap.sdus_mask * 512;
+	}
+
+	hba->caps |= UFSHCD_CAP_CRYPTO;
+	hba->quirks |= UFSHCD_QUIRK_CUSTOM_CRYPTO_PROFILE;
 	return 0;
 }
 
@@ -149,32 +186,49 @@ static inline int ufs_qcom_ice_suspend(struct ufs_qcom_host *host)
 	return 0;
 }
 
-static int ufs_qcom_ice_program_key(struct ufs_hba *hba,
-				    const union ufs_crypto_cfg_entry *cfg,
-				    int slot)
+static int ufs_qcom_ice_keyslot_program(struct blk_crypto_profile *profile,
+					const struct blk_crypto_key *key,
+					unsigned int slot)
 {
+	struct ufs_hba *hba = ufs_hba_from_crypto_profile(profile);
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
-	union ufs_crypto_cap_entry cap;
-
-	if (!(cfg->config_enable & UFS_CRYPTO_CONFIGURATION_ENABLE))
-		return qcom_ice_evict_key(host->ice, slot);
+	int err;
 
 	/* Only AES-256-XTS has been tested so far. */
-	cap = hba->crypto_cap_array[cfg->crypto_cap_idx];
-	if (cap.algorithm_id != UFS_CRYPTO_ALG_AES_XTS ||
-	    cap.key_size != UFS_CRYPTO_KEY_SIZE_256)
+	if (key->crypto_cfg.crypto_mode != BLK_ENCRYPTION_MODE_AES_256_XTS)
 		return -EOPNOTSUPP;
 
-	return qcom_ice_program_key(host->ice,
-				    QCOM_ICE_CRYPTO_ALG_AES_XTS,
-				    QCOM_ICE_CRYPTO_KEY_SIZE_256,
-				    cfg->crypto_key,
-				    cfg->data_unit_size, slot);
+	ufshcd_hold(hba);
+	err = qcom_ice_program_key(host->ice,
+				   QCOM_ICE_CRYPTO_ALG_AES_XTS,
+				   QCOM_ICE_CRYPTO_KEY_SIZE_256,
+				   key->raw,
+				   key->crypto_cfg.data_unit_size / 512,
+				   slot);
+	ufshcd_release(hba);
+	return err;
 }
 
-#else
+static int ufs_qcom_ice_keyslot_evict(struct blk_crypto_profile *profile,
+				      const struct blk_crypto_key *key,
+				      unsigned int slot)
+{
+	struct ufs_hba *hba = ufs_hba_from_crypto_profile(profile);
+	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	int err;
+
+	ufshcd_hold(hba);
+	err = qcom_ice_evict_key(host->ice, slot);
+	ufshcd_release(hba);
+	return err;
+}
 
-#define ufs_qcom_ice_program_key NULL
+static const struct blk_crypto_ll_ops ufs_qcom_crypto_ops = {
+	.keyslot_program	= ufs_qcom_ice_keyslot_program,
+	.keyslot_evict		= ufs_qcom_ice_keyslot_evict,
+};
+
+#else
 
 static inline void ufs_qcom_ice_enable(struct ufs_qcom_host *host)
 {
@@ -1822,7 +1876,6 @@ static const struct ufs_hba_variant_ops ufs_hba_qcom_vops = {
 	.dbg_register_dump	= ufs_qcom_dump_dbg_regs,
 	.device_reset		= ufs_qcom_device_reset,
 	.config_scaling_param = ufs_qcom_config_scaling_param,
-	.program_key		= ufs_qcom_ice_program_key,
 	.reinit_notify		= ufs_qcom_reinit_notify,
 	.mcq_config_resource	= ufs_qcom_mcq_config_resource,
 	.get_hba_mac		= ufs_qcom_get_hba_mac,