mmc: crypto: add mmc_from_crypto_profile()

Add a helper function that encapsulates a container_of expression.  For
now there is just one user but soon there will be more.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Message-ID: <20241213041958.202565-7-ebiggers@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Author: ebiggers

drivers/mmc/host/cqhci-crypto.c

@@ -25,10 +25,7 @@ static const struct cqhci_crypto_alg_entry {
 static inline struct cqhci_host *
 cqhci_host_from_crypto_profile(struct blk_crypto_profile *profile)
 {
-	struct mmc_host *mmc =
-		container_of(profile, struct mmc_host, crypto_profile);
-
-	return mmc->cqe_private;
+	return mmc_from_crypto_profile(profile)->cqe_private;
 }
 
 static int cqhci_crypto_program_key(struct cqhci_host *cq_host,

include/linux/mmc/host.h

@@ -590,6 +590,14 @@ static inline struct mmc_host *mmc_from_priv(void *priv)
 	return container_of(priv, struct mmc_host, private);
 }
 
+#ifdef CONFIG_MMC_CRYPTO
+static inline struct mmc_host *
+mmc_from_crypto_profile(struct blk_crypto_profile *profile)
+{
+	return container_of(profile, struct mmc_host, crypto_profile);
+}
+#endif
+
 #define mmc_host_is_spi(host)	((host)->caps & MMC_CAP_SPI)
 
 #define mmc_dev(x)	((x)->parent)