[PATCH v6] tpm: separate cmd_ready/go_idle from runtime_pm
From: Tomas Winkler
Date: Thu Jun 07 2018 - 17:21:14 EST
We cannot use go_idle cmd_ready commands via runtime_pm handles
as with the introduction of localities this is no longer an optional
feature, while runtime pm can be not enabled.
Though cmd_ready/go_idle provides a power saving, it's also a part of
TPM2 protocol and should be called explicitly.
This patch exposes cmd_read/go_idle via tpm class ops and removes
runtime pm support as it is not used by any driver.
A new tpm transmit flag is added TPM_TRANSMIT_NESTED, which implies
TPM_TRANSMIT_UNLOCKED and TPM_TRANSMIT_RAW. Both are needed to resolve
tpm spaces and locality request recursive calls to tpm_transmit().
New wrappers are added tpm_cmd_ready() and tpm_go_idle() to
streamline tpm_try_transmit code.
tpm_crb no longer needs own power saving functions and can drop using
tpm_pm_suspend/resume.
This patch cannot be really separated from the locality fix.
Fixes: 888d867df441 (tpm: cmd_ready command can be issued only after granting locality)
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 888d867df441 (tpm: cmd_ready command can be issued only after granting locality)
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
---
V2-3:resent
V4: 1. Use tpm_pm_suspend/resume in tpm_crb
2. Drop cmd_ready/go_idle around tpm_chip_register, as there is no
usage counter like in runtime_pm.
V5: 1. add tpm_cmd_ready and tpm_go_idle wrappers.
2. Abuse TPM_TRANSMIT_UNLOCKED flag to resolve tpm space
recursion.
V6: 1. Add new flags TPM_TRANSMIT_NESTED which implies
TPM_TRANSMIT_UNLOCKED and TPM_TRANSMIT_RAW, as not all
unlocked flows are recursive i.e. tpm2_unseal_trusted.
drivers/char/tpm/tpm-interface.c | 51 +++++++++++++++----
drivers/char/tpm/tpm.h | 13 ++++-
drivers/char/tpm/tpm2-space.c | 12 ++---
drivers/char/tpm/tpm_crb.c | 101 ++++++++++----------------------------
drivers/char/tpm/tpm_vtpm_proxy.c | 2 +-
include/linux/tpm.h | 2 +
6 files changed, 88 insertions(+), 93 deletions(-)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index e32f6e85dc6d..1abd8261651b 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -29,7 +29,6 @@
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/freezer.h>
-#include <linux/pm_runtime.h>
#include <linux/tpm_eventlog.h>
#include "tpm.h"
@@ -369,10 +368,13 @@ static int tpm_validate_command(struct tpm_chip *chip,
return -EINVAL;
}
-static int tpm_request_locality(struct tpm_chip *chip)
+static int tpm_request_locality(struct tpm_chip *chip, unsigned int flags)
{
int rc;
+ if (flags & __TPM_TRANSMIT_RAW)
+ return 0;
+
if (!chip->ops->request_locality)
return 0;
@@ -385,10 +387,13 @@ static int tpm_request_locality(struct tpm_chip *chip)
return 0;
}
-static void tpm_relinquish_locality(struct tpm_chip *chip)
+static void tpm_relinquish_locality(struct tpm_chip *chip, unsigned int flags)
{
int rc;
+ if (flags & __TPM_TRANSMIT_RAW)
+ return;
+
if (!chip->ops->relinquish_locality)
return;
@@ -399,6 +404,28 @@ static void tpm_relinquish_locality(struct tpm_chip *chip)
chip->locality = -1;
}
+static int tpm_cmd_ready(struct tpm_chip *chip, unsigned int flags)
+{
+ if (flags & __TPM_TRANSMIT_RAW)
+ return 0;
+
+ if (!chip->ops->cmd_ready)
+ return 0;
+
+ return chip->ops->cmd_ready(chip);
+}
+
+static int tpm_go_idle(struct tpm_chip *chip, unsigned int flags)
+{
+ if (flags & __TPM_TRANSMIT_RAW)
+ return 0;
+
+ if (!chip->ops->go_idle)
+ return 0;
+
+ return chip->ops->go_idle(chip);
+}
+
static ssize_t tpm_try_transmit(struct tpm_chip *chip,
struct tpm_space *space,
u8 *buf, size_t bufsiz,
@@ -449,14 +476,15 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
/* Store the decision as chip->locality will be changed. */
need_locality = chip->locality == -1;
- if (!(flags & TPM_TRANSMIT_RAW) && need_locality) {
- rc = tpm_request_locality(chip);
+ if (need_locality) {
+ rc = tpm_request_locality(chip, flags);
if (rc < 0)
goto out_no_locality;
}
- if (chip->dev.parent)
- pm_runtime_get_sync(chip->dev.parent);
+ rc = tpm_cmd_ready(chip, flags);
+ if (rc)
+ goto out;
rc = tpm2_prepare_space(chip, space, ordinal, buf);
if (rc)
@@ -516,13 +544,16 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
}
rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
+ if (rc)
+ dev_err(&chip->dev, "tpm2_commit_space: error %d\n", rc);
out:
- if (chip->dev.parent)
- pm_runtime_put_sync(chip->dev.parent);
+ rc = tpm_go_idle(chip, flags);
+ if (rc)
+ goto out;
if (need_locality)
- tpm_relinquish_locality(chip);
+ tpm_relinquish_locality(chip, flags);
out_no_locality:
if (chip->ops->clk_enable != NULL)
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 4426649e431c..beb0a763016c 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -511,9 +511,18 @@ extern const struct file_operations tpm_fops;
extern const struct file_operations tpmrm_fops;
extern struct idr dev_nums_idr;
+/**
+ * enum tpm_transmit_flags
+ *
+ * @TPM_TRANSMIT_UNLOCKED: used to lock sequence of tpm_transmit calls.
+ * @__TPM_TRANSMIT_RAW: prevent recursive calls into setup steps
+ * (go idle, locality,..). Don't use directly.
+ * @TPM_TRANSMIT_NESTED: Use from nested tpm_transmit calls
+ */
enum tpm_transmit_flags {
- TPM_TRANSMIT_UNLOCKED = BIT(0),
- TPM_TRANSMIT_RAW = BIT(1),
+ TPM_TRANSMIT_UNLOCKED = BIT(0),
+ __TPM_TRANSMIT_RAW = BIT(1),
+ TPM_TRANSMIT_NESTED = TPM_TRANSMIT_UNLOCKED | __TPM_TRANSMIT_RAW,
};
ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index 6122d3276f72..d2e101b32482 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -39,7 +39,7 @@ static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space)
for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++) {
if (space->session_tbl[i])
tpm2_flush_context_cmd(chip, space->session_tbl[i],
- TPM_TRANSMIT_UNLOCKED);
+ TPM_TRANSMIT_NESTED);
}
}
@@ -84,7 +84,7 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
tpm_buf_append(&tbuf, &buf[*offset], body_size);
rc = tpm_transmit_cmd(chip, NULL, tbuf.data, PAGE_SIZE, 4,
- TPM_TRANSMIT_UNLOCKED, NULL);
+ TPM_TRANSMIT_NESTED, NULL);
if (rc < 0) {
dev_warn(&chip->dev, "%s: failed with a system error %d\n",
__func__, rc);
@@ -133,7 +133,7 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
tpm_buf_append_u32(&tbuf, handle);
rc = tpm_transmit_cmd(chip, NULL, tbuf.data, PAGE_SIZE, 0,
- TPM_TRANSMIT_UNLOCKED, NULL);
+ TPM_TRANSMIT_NESTED, NULL);
if (rc < 0) {
dev_warn(&chip->dev, "%s: failed with a system error %d\n",
__func__, rc);
@@ -170,7 +170,7 @@ static void tpm2_flush_space(struct tpm_chip *chip)
for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++)
if (space->context_tbl[i] && ~space->context_tbl[i])
tpm2_flush_context_cmd(chip, space->context_tbl[i],
- TPM_TRANSMIT_UNLOCKED);
+ TPM_TRANSMIT_NESTED);
tpm2_flush_sessions(chip, space);
}
@@ -377,7 +377,7 @@ static int tpm2_map_response_header(struct tpm_chip *chip, u32 cc, u8 *rsp,
return 0;
out_no_slots:
- tpm2_flush_context_cmd(chip, phandle, TPM_TRANSMIT_UNLOCKED);
+ tpm2_flush_context_cmd(chip, phandle, TPM_TRANSMIT_NESTED);
dev_warn(&chip->dev, "%s: out of slots for 0x%08X\n", __func__,
phandle);
return -ENOMEM;
@@ -465,7 +465,7 @@ static int tpm2_save_space(struct tpm_chip *chip)
return rc;
tpm2_flush_context_cmd(chip, space->context_tbl[i],
- TPM_TRANSMIT_UNLOCKED);
+ TPM_TRANSMIT_NESTED);
space->context_tbl[i] = ~0;
}
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index 34fbc6cb097b..36952ef98f90 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -132,7 +132,7 @@ static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
}
/**
- * crb_go_idle - request tpm crb device to go the idle state
+ * __crb_go_idle - request tpm crb device to go the idle state
*
* @dev: crb device
* @priv: crb private data
@@ -147,7 +147,7 @@ static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
*
* Return: 0 always
*/
-static int crb_go_idle(struct device *dev, struct crb_priv *priv)
+static int __crb_go_idle(struct device *dev, struct crb_priv *priv)
{
if ((priv->sm == ACPI_TPM2_START_METHOD) ||
(priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
@@ -163,11 +163,20 @@ static int crb_go_idle(struct device *dev, struct crb_priv *priv)
dev_warn(dev, "goIdle timed out\n");
return -ETIME;
}
+
return 0;
}
+static int crb_go_idle(struct tpm_chip *chip)
+{
+ struct device *dev = &chip->dev;
+ struct crb_priv *priv = dev_get_drvdata(dev);
+
+ return __crb_go_idle(dev, priv);
+}
+
/**
- * crb_cmd_ready - request tpm crb device to enter ready state
+ * __crb_cmd_ready - request tpm crb device to enter ready state
*
* @dev: crb device
* @priv: crb private data
@@ -181,7 +190,7 @@ static int crb_go_idle(struct device *dev, struct crb_priv *priv)
*
* Return: 0 on success -ETIME on timeout;
*/
-static int crb_cmd_ready(struct device *dev, struct crb_priv *priv)
+static int __crb_cmd_ready(struct device *dev, struct crb_priv *priv)
{
if ((priv->sm == ACPI_TPM2_START_METHOD) ||
(priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
@@ -200,6 +209,14 @@ static int crb_cmd_ready(struct device *dev, struct crb_priv *priv)
return 0;
}
+static int crb_cmd_ready(struct tpm_chip *chip)
+{
+ struct device *dev = &chip->dev;
+ struct crb_priv *priv = dev_get_drvdata(dev);
+
+ return __crb_cmd_ready(dev, priv);
+}
+
static int __crb_request_locality(struct device *dev,
struct crb_priv *priv, int loc)
{
@@ -401,6 +418,8 @@ static const struct tpm_class_ops tpm_crb = {
.send = crb_send,
.cancel = crb_cancel,
.req_canceled = crb_req_canceled,
+ .go_idle = crb_go_idle,
+ .cmd_ready = crb_cmd_ready,
.request_locality = crb_request_locality,
.relinquish_locality = crb_relinquish_locality,
.req_complete_mask = CRB_DRV_STS_COMPLETE,
@@ -520,7 +539,7 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
* PTT HW bug w/a: wake up the device to access
* possibly not retained registers.
*/
- ret = crb_cmd_ready(dev, priv);
+ ret = __crb_cmd_ready(dev, priv);
if (ret)
goto out_relinquish_locality;
@@ -565,7 +584,7 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
if (!ret)
priv->cmd_size = cmd_size;
- crb_go_idle(dev, priv);
+ __crb_go_idle(dev, priv);
out_relinquish_locality:
@@ -628,32 +647,7 @@ static int crb_acpi_add(struct acpi_device *device)
chip->acpi_dev_handle = device->handle;
chip->flags = TPM_CHIP_FLAG_TPM2;
- rc = __crb_request_locality(dev, priv, 0);
- if (rc)
- return rc;
-
- rc = crb_cmd_ready(dev, priv);
- if (rc)
- goto out;
-
- pm_runtime_get_noresume(dev);
- pm_runtime_set_active(dev);
- pm_runtime_enable(dev);
-
- rc = tpm_chip_register(chip);
- if (rc) {
- crb_go_idle(dev, priv);
- pm_runtime_put_noidle(dev);
- pm_runtime_disable(dev);
- goto out;
- }
-
- pm_runtime_put_sync(dev);
-
-out:
- __crb_relinquish_locality(dev, priv, 0);
-
- return rc;
+ return tpm_chip_register(chip);
}
static int crb_acpi_remove(struct acpi_device *device)
@@ -663,52 +657,11 @@ static int crb_acpi_remove(struct acpi_device *device)
tpm_chip_unregister(chip);
- pm_runtime_disable(dev);
-
return 0;
}
-static int __maybe_unused crb_pm_runtime_suspend(struct device *dev)
-{
- struct tpm_chip *chip = dev_get_drvdata(dev);
- struct crb_priv *priv = dev_get_drvdata(&chip->dev);
-
- return crb_go_idle(dev, priv);
-}
-
-static int __maybe_unused crb_pm_runtime_resume(struct device *dev)
-{
- struct tpm_chip *chip = dev_get_drvdata(dev);
- struct crb_priv *priv = dev_get_drvdata(&chip->dev);
-
- return crb_cmd_ready(dev, priv);
-}
-
-static int __maybe_unused crb_pm_suspend(struct device *dev)
-{
- int ret;
-
- ret = tpm_pm_suspend(dev);
- if (ret)
- return ret;
-
- return crb_pm_runtime_suspend(dev);
-}
-
-static int __maybe_unused crb_pm_resume(struct device *dev)
-{
- int ret;
-
- ret = crb_pm_runtime_resume(dev);
- if (ret)
- return ret;
-
- return tpm_pm_resume(dev);
-}
-
static const struct dev_pm_ops crb_pm = {
- SET_SYSTEM_SLEEP_PM_OPS(crb_pm_suspend, crb_pm_resume)
- SET_RUNTIME_PM_OPS(crb_pm_runtime_suspend, crb_pm_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(tpm_pm_suspend, tpm_pm_resume)
};
static const struct acpi_device_id crb_device_ids[] = {
diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
index e4f79f920450..87a0ce47f201 100644
--- a/drivers/char/tpm/tpm_vtpm_proxy.c
+++ b/drivers/char/tpm/tpm_vtpm_proxy.c
@@ -418,7 +418,7 @@ static int vtpm_proxy_request_locality(struct tpm_chip *chip, int locality)
proxy_dev->state |= STATE_DRIVER_COMMAND;
rc = tpm_transmit_cmd(chip, NULL, buf.data, tpm_buf_length(&buf), 0,
- TPM_TRANSMIT_UNLOCKED | TPM_TRANSMIT_RAW,
+ TPM_TRANSMIT_NESTED,
"attempting to set locality");
proxy_dev->state &= ~STATE_DRIVER_COMMAND;
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 06639fb6ab85..8eb5e5ebe136 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -43,6 +43,8 @@ struct tpm_class_ops {
u8 (*status) (struct tpm_chip *chip);
bool (*update_timeouts)(struct tpm_chip *chip,
unsigned long *timeout_cap);
+ int (*go_idle)(struct tpm_chip *chip);
+ int (*cmd_ready)(struct tpm_chip *chip);
int (*request_locality)(struct tpm_chip *chip, int loc);
int (*relinquish_locality)(struct tpm_chip *chip, int loc);
void (*clk_enable)(struct tpm_chip *chip, bool value);
--
2.14.4