[PATCH v9 09/11] tpm-buf: Remove tpm_buf_append_handle

[Jarkko Sakkinen <jarkko@kernel.org>]

Since the number of handles is fixed to a single handle, eliminate all uses
of buf->handles and deduce values during compile-time.

Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
v2:
- Streamline the code change and remove dead code.
---
 drivers/char/tpm/tpm-buf.c       | 23 -----------------------
 drivers/char/tpm/tpm2-cmd.c      |  2 +-
 drivers/char/tpm/tpm2-sessions.c | 14 ++------------
 include/linux/tpm.h              |  2 --
 4 files changed, 3 insertions(+), 38 deletions(-)

diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index dc882fc9fa9e..1d2b87455d3a 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c
@@ -44,7 +44,6 @@ void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal)
 	head->tag = cpu_to_be16(tag);
 	head->length = cpu_to_be32(sizeof(*head));
 	head->ordinal = cpu_to_be32(ordinal);
-	buf->handles = 0;
 }
 EXPORT_SYMBOL_GPL(tpm_buf_reset);
 
@@ -146,26 +145,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
 }
 EXPORT_SYMBOL_GPL(tpm_buf_append_u32);
 
-/**
- * tpm_buf_append_handle() - Add a handle
- * @chip:	&tpm_chip instance
- * @buf:	&tpm_buf instance
- * @handle:	a TPM object handle
- *
- * Add a handle to the buffer, and increase the count tracking the number of
- * handles in the command buffer. Works only for command buffers.
- */
-void tpm_buf_append_handle(struct tpm_chip *chip, struct tpm_buf *buf, u32 handle)
-{
-	if (buf->flags & TPM_BUF_TPM2B) {
-		dev_err(&chip->dev, "Invalid buffer type (TPM2B)\n");
-		return;
-	}
-
-	tpm_buf_append_u32(buf, handle);
-	buf->handles++;
-}
-
 /**
  * tpm_buf_read() - Read from a TPM buffer
  * @buf:	&tpm_buf instance
@@ -242,5 +221,3 @@ u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset)
 	return be32_to_cpu(value);
 }
 EXPORT_SYMBOL_GPL(tpm_buf_read_u32);
-
-
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 96a45391036c..39ef6b7a0fbc 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -210,7 +210,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
 		}
 		tpm_buf_append_hmac_session(chip, &buf, 0, NULL, 0);
 	} else {
-		tpm_buf_append_handle(chip, &buf, pcr_idx);
+		tpm_buf_append_u32(&buf, pcr_idx);
 		tpm_buf_append_auth(chip, &buf, NULL, 0);
 	}
 
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 98cea20040cf..016bed63a755 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -268,7 +268,7 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
 	}
 
 	if (!tpm2_chip_auth(chip)) {
-		tpm_buf_append_handle(chip, buf, handle);
+		tpm_buf_append_u32(buf, handle);
 		return 0;
 	}
 
@@ -295,17 +295,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_append_name);
 void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
 			 u8 *passphrase, int passphrase_len)
 {
-	/* offset tells us where the sessions area begins */
-	int offset = buf->handles * 4 + TPM_HEADER_SIZE;
-	u32 len = 9 + passphrase_len;
-
-	if (tpm_buf_length(buf) != offset) {
-		/* not the first session so update the existing length */
-		len += get_unaligned_be32(&buf->data[offset]);
-		put_unaligned_be32(len, &buf->data[offset]);
-	} else {
-		tpm_buf_append_u32(buf, len);
-	}
+	tpm_buf_append_u32(buf, 9 + passphrase_len);
 	/* auth handle */
 	tpm_buf_append_u32(buf, TPM2_RS_PW);
 	/* nonce */
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 7468709ad245..e8339f0c9a2e 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -397,7 +397,6 @@ struct tpm_buf {
 	u32 flags;
 	u32 length;
 	u8 *data;
-	u8 handles;
 };
 
 enum tpm2_object_attributes {
@@ -441,7 +440,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value);
 u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset);
 u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset);
 u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset);
-void tpm_buf_append_handle(struct tpm_chip *chip, struct tpm_buf *buf, u32 handle);
 
 /*
  * Check if TPM device is in the firmware upgrade mode.
-- 
2.52.0