#include <linux/poll.h>
#include <linux/slab.h>
+#include <linux/jiffies.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/freezer.h>
mutex_unlock(&chip->buffer_mutex);
}
-/*
- * Returns max number of jiffies to wait
- */
-unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
- u32 ordinal)
+static void set_needs_resume(struct tpm_chip *chip)
{
- int duration_idx = TPM_UNDEFINED;
- int duration = 0;
+ mutex_lock(&chip->resume_mutex);
+ chip->resume_time = jiffies;
+ chip->needs_resume = 1;
+ mutex_unlock(&chip->resume_mutex);
+}
- if (ordinal < TPM_MAX_ORDINAL)
- duration_idx = tpm_ordinal_duration[ordinal];
- else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
- TPM_MAX_PROTECTED_ORDINAL)
- duration_idx =
- tpm_protected_ordinal_duration[ordinal &
- TPM_PROTECTED_ORDINAL_MASK];
+#define TPM_ORD_CONTINUE_SELFTEST 83
+#define CONTINUE_SELFTEST_RESULT_SIZE 10
- if (duration_idx != TPM_UNDEFINED)
- duration = chip->vendor.duration[duration_idx];
- if (duration <= 0)
- return 2 * 60 * HZ;
- else
- return duration;
-}
-EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
+#define TPM_INTERNAL_RESULT_SIZE 200
+#define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
+#define TPM_ORD_GET_CAP cpu_to_be32(101)
+
+static const struct tpm_input_header tpm_getcap_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(22),
+ .ordinal = TPM_ORD_GET_CAP
+};
+
+static struct tpm_input_header continue_selftest_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(10),
+ .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
+};
/*
* Internal kernel interface to transmit TPM commands
return rc;
}
-#define TPM_DIGEST_SIZE 20
-#define TPM_RET_CODE_IDX 6
-
-enum tpm_capabilities {
- TPM_CAP_FLAG = cpu_to_be32(4),
- TPM_CAP_PROP = cpu_to_be32(5),
- CAP_VERSION_1_1 = cpu_to_be32(0x06),
- CAP_VERSION_1_2 = cpu_to_be32(0x1A)
-};
-
-enum tpm_sub_capabilities {
- TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
- TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
- TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
- TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
- TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
- TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
- TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
+void tpm_continue_selftest_nocheck(struct tpm_chip *chip)
+{
+ struct tpm_cmd_t cmd;
+ cmd.header.in = continue_selftest_header;
+ tpm_transmit(chip, (u8 *) &cmd, CONTINUE_SELFTEST_RESULT_SIZE);
+}
-};
+/* The maximum time in milliseconds that the TPM self test will take to
+ * complete. TODO(semenzato): 1s should be plenty for all TPMs, but how can we
+ * ensure it?
+ */
+#define TPM_SELF_TEST_DURATION_MSEC 1000
+
+/* We don't want to wait for the self test to complete at resume, because it
+ * impacts the resume speed. TPM commands are infrequent so the wait is
+ * usually not needed and is wasteful. Instead, before we send any command, we
+ * check that enough time has elapsed from the resume so that we are
+ * comfortable that the self test has completed. If not, we wait. Unlike at
+ * boot, here we don't check the return code of continue_self_test, so we can
+ * use a code path which avoids recursion. Furthermore, this only works when
+ * ContinueSelfTest is blocking, that is it returns only after the self test
+ * has completed, which is the case for the Infineon TPM.
+ */
+static void resume_if_needed(struct tpm_chip *chip)
+{
+ mutex_lock(&chip->resume_mutex);
+ if (chip->needs_resume) {
+ /* If it's been TPM_SELF_TEST_DURATION_MSEC msec since resume,
+ * then selftest has completed and we don't need to wait.
+ */
+ if (jiffies - chip->resume_time <
+ msecs_to_jiffies(TPM_SELF_TEST_DURATION_MSEC)) {
+ dev_info(chip->dev, "waiting for TPM self test");
+ tpm_continue_selftest_nocheck(chip);
+ }
+ chip->needs_resume = 0;
+ dev_info(chip->dev, "TPM delayed resume completed");
+ }
+ mutex_unlock(&chip->resume_mutex);
+}
static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
int len, const char *desc)
{
int err;
+ resume_if_needed(chip);
+
len = tpm_transmit(chip,(u8 *) cmd, len);
if (len < 0)
return len;
return err;
}
-#define TPM_INTERNAL_RESULT_SIZE 200
-#define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
-#define TPM_ORD_GET_CAP cpu_to_be32(101)
+/**
+ * tpm_continue_selftest -- run TPM's selftest
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
+ * a TPM error code.
+ */
+int tpm_continue_selftest(struct tpm_chip *chip)
+{
+ int rc;
+ struct tpm_cmd_t cmd;
+
+ cmd.header.in = continue_selftest_header;
+ rc = transmit_cmd(chip, (const u8 *) &cmd,
+ CONTINUE_SELFTEST_RESULT_SIZE, "continue selftest");
+ return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_continue_selftest);
+
+/*
+ * Returns max number of jiffies to wait
+ */
+unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
+ u32 ordinal)
+{
+ int duration_idx = TPM_UNDEFINED;
+ int duration = 0;
+
+ if (ordinal < TPM_MAX_ORDINAL)
+ duration_idx = tpm_ordinal_duration[ordinal];
+ else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
+ TPM_MAX_PROTECTED_ORDINAL)
+ duration_idx =
+ tpm_protected_ordinal_duration[ordinal &
+ TPM_PROTECTED_ORDINAL_MASK];
+
+ if (duration_idx != TPM_UNDEFINED)
+ duration = chip->vendor.duration[duration_idx];
+ if (duration <= 0)
+ return 2 * 60 * HZ;
+ else
+ return duration;
+}
+EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
+
+#define TPM_DIGEST_SIZE 20
+#define TPM_RET_CODE_IDX 6
+
+enum tpm_capabilities {
+ TPM_CAP_FLAG = cpu_to_be32(4),
+ TPM_CAP_PROP = cpu_to_be32(5),
+ CAP_VERSION_1_1 = cpu_to_be32(0x06),
+ CAP_VERSION_1_2 = cpu_to_be32(0x1A)
+};
+
+enum tpm_sub_capabilities {
+ TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
+ TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
+ TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
+ TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
+ TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
+ TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
+ TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
-static const struct tpm_input_header tpm_getcap_header = {
- .tag = TPM_TAG_RQU_COMMAND,
- .length = cpu_to_be32(22),
- .ordinal = TPM_ORD_GET_CAP
};
ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
}
EXPORT_SYMBOL_GPL(tpm_get_timeouts);
-#define TPM_ORD_CONTINUE_SELFTEST 83
-#define CONTINUE_SELFTEST_RESULT_SIZE 10
-
-static struct tpm_input_header continue_selftest_header = {
- .tag = TPM_TAG_RQU_COMMAND,
- .length = cpu_to_be32(10),
- .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
-};
-
-/**
- * tpm_continue_selftest -- run TPM's selftest
- * @chip: TPM chip to use
- *
- * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
- * a TPM error code.
- */
-static int tpm_continue_selftest(struct tpm_chip *chip)
-{
- int rc;
- struct tpm_cmd_t cmd;
-
- cmd.header.in = continue_selftest_header;
- rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
- "continue selftest");
- return rc;
-}
-
ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
char *buf)
{
be32_to_cpu(cap.manufacturer_id));
rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
- "attempting to determine the 1.1 version");
+ "attempting to determine the 1.1 version");
if (rc)
return 0;
str += sprintf(str,
while (atomic_read(&chip->data_pending) != 0)
msleep(TPM_TIMEOUT);
+ resume_if_needed(chip);
+
mutex_lock(&chip->buffer_mutex);
if (in_size > TPM_BUFSIZE)
del_singleshot_timer_sync(&chip->user_read_timer);
flush_work_sync(&chip->work);
ret_size = atomic_read(&chip->data_pending);
+ /* TODO(wad): atomic_set should come AFTER the buffer is copied. */
atomic_set(&chip->data_pending, 0);
if (ret_size > 0) { /* relay data */
ssize_t orig_ret_size = ret_size;
if (chip == NULL)
return -ENODEV;
+ set_needs_resume(chip);
return 0;
}
EXPORT_SYMBOL_GPL(tpm_pm_resume);
mutex_init(&chip->buffer_mutex);
mutex_init(&chip->tpm_mutex);
+ mutex_init(&chip->resume_mutex);
INIT_LIST_HEAD(&chip->list);
INIT_WORK(&chip->work, timeout_work);
projects / cascardo / linux.git / blobdiff