These interfaces are located in /sys/devices/platform/txt/log/.
Signed-off-by: Qiaowei Ren <[email protected]>
Signed-off-by: Xiaoyan Zhang <[email protected]>
Signed-off-by: Gang Wei <[email protected]>
---
drivers/char/txt/Makefile | 2 +-
drivers/char/txt/txt-log.c | 140 ++++++++++++++++++++++++++++++++++++++++++
drivers/char/txt/txt-log.h | 27 ++++++++
drivers/char/txt/txt-sysfs.c | 5 ++
4 files changed, 173 insertions(+), 1 deletion(-)
create mode 100644 drivers/char/txt/txt-log.c
create mode 100644 drivers/char/txt/txt-log.h
diff --git a/drivers/char/txt/Makefile b/drivers/char/txt/Makefile
index 3db5a6f..fcb0e81 100644
--- a/drivers/char/txt/Makefile
+++ b/drivers/char/txt/Makefile
@@ -2,4 +2,4 @@
# Makefile for the intel TXT drivers.
#
obj-$(CONFIG_TXT) += txt.o
-txt-y := txt-sysfs.o txt-config.o
+txt-y := txt-sysfs.o txt-config.o txt-log.o
diff --git a/drivers/char/txt/txt-log.c b/drivers/char/txt/txt-log.c
new file mode 100644
index 0000000..10f3918
--- /dev/null
+++ b/drivers/char/txt/txt-log.c
@@ -0,0 +1,140 @@
+/*
+ * txt-log.c
+ *
+ * - log/
+ * log_header -r--r--r-- ; output log header, including max_size and
+ * curr_pos.
+ * block -r--r--r-- ; output pure log in block style, 1 page size.
+ * block_index -rw-rw-r-- ; the block index for output.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sysfs.h>
+#include <linux/io.h>
+#include <linux/stat.h>
+
+#include "txt-log.h"
+
+static u32 log_block_index;
+
+static int are_uuids_equal(const struct uuid *uuid1,
+ const struct uuid *uuid2)
+{
+ return (memcmp(uuid1, uuid2, sizeof(*uuid1)) == 0) ? 1 : 0;
+}
+
+static struct tboot_log *get_log(void)
+{
+ struct tboot_log *log;
+
+ log = (struct tboot_log *)ioremap_nocache(TBOOT_SERIAL_LOG_ADDR,
+ TBOOT_SERIAL_LOG_SIZE);
+ if (!log)
+ return NULL;
+
+ if (!are_uuids_equal(&(log->uuid),
+ &((struct uuid)TBOOT_LOG_UUID))) {
+ iounmap(log);
+ return NULL;
+ }
+
+ return log;
+}
+
+ssize_t txt_show_log_header(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct tboot_log *log;
+ int ret;
+
+ log = get_log();
+ if (!log)
+ return -EFAULT;
+
+ ret = scnprintf(buf, PAGE_SIZE, "max_size: %x\ncurr_pos: %x\n",
+ log->max_size, log->curr_pos);
+
+ iounmap(log);
+ return ret;
+}
+static DEVICE_ATTR(log_header, S_IRUGO, txt_show_log_header, NULL);
+
+ssize_t txt_show_block(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tboot_log *log;
+ char *block;
+ int ret;
+
+ log = get_log();
+ if (!log)
+ return -EFAULT;
+
+ block = log->buf + log_block_index * PAGE_SIZE;
+ ret = scnprintf(buf, PAGE_SIZE, "%s\n", block);
+
+ iounmap(log);
+ return ret;
+}
+static DEVICE_ATTR(block, S_IRUGO, txt_show_block, NULL);
+
+ssize_t txt_show_block_index(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return scnprintf(buf, PAGE_SIZE, "%d\n", log_block_index);
+}
+
+ssize_t txt_store_block_index(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ u32 index;
+ struct tboot_log *log;
+
+ log = get_log();
+ if (!log)
+ return -EFAULT;
+
+ sscanf(buf, "%d", &index);
+ if (index > log->curr_pos / PAGE_SIZE)
+ return -EINVAL;
+ log_block_index = index;
+
+ iounmap(log);
+ return count;
+}
+static DEVICE_ATTR(block_index, S_IRUGO | S_IWUSR | S_IWGRP,
+ txt_show_block_index, txt_store_block_index);
+
+static struct attribute *log_attrs[] = {
+ &dev_attr_log_header.attr,
+ &dev_attr_block.attr,
+ &dev_attr_block_index.attr,
+ NULL,
+};
+
+static struct attribute_group log_attr_grp = {
+ .attrs = log_attrs
+};
+
+ssize_t sysfs_create_log(struct kobject *parent)
+{
+ struct kobject *log_kobj;
+ int retval;
+
+ log_kobj = kobject_create_and_add("log", parent);
+ if (!log_kobj)
+ return -ENOMEM;
+
+ retval = sysfs_create_group(log_kobj, &log_attr_grp);
+ if (retval)
+ kobject_put(log_kobj);
+ return retval;
+}
+EXPORT_SYMBOL_GPL(sysfs_create_log);
+
+MODULE_LICENSE("GPL");
+
diff --git a/drivers/char/txt/txt-log.h b/drivers/char/txt/txt-log.h
new file mode 100644
index 0000000..580d71c
--- /dev/null
+++ b/drivers/char/txt/txt-log.h
@@ -0,0 +1,27 @@
+#ifndef __LOG_H__
+#define __LOG_H__
+
+struct uuid {
+ uint32_t data1;
+ uint16_t data2;
+ uint16_t data3;
+ uint16_t data4;
+ uint8_t data5[6];
+} __packed;
+
+struct tboot_log {
+ struct uuid uuid;
+ uint32_t max_size;
+ uint32_t curr_pos;
+ char buf[];
+};
+
+#define TBOOT_LOG_UUID {0xc0192526, 0x6b30, 0x4db4, 0x844c, \
+ {0xa3, 0xe9, 0x53, 0xb8, 0x81, 0x74} }
+#define TBOOT_SERIAL_LOG_ADDR 0x60000
+#define TBOOT_SERIAL_LOG_SIZE 0x08000
+
+extern ssize_t sysfs_create_log(struct kobject *parent);
+
+#endif /* __LOG_H__ */
+
diff --git a/drivers/char/txt/txt-sysfs.c b/drivers/char/txt/txt-sysfs.c
index 99d42d0..e945586 100644
--- a/drivers/char/txt/txt-sysfs.c
+++ b/drivers/char/txt/txt-sysfs.c
@@ -17,6 +17,7 @@
#include <linux/sysfs.h>
#include "txt-config.h"
+#include "txt-log.h"
#define DEV_NAME "txt"
struct platform_device *pdev;
@@ -33,6 +34,10 @@ static int __init txt_sysfs_init(void)
if (retval)
goto err;
+ retval = sysfs_create_log(&pdev->dev.kobj);
+ if (retval)
+ goto err;
+
pr_info("Loading TXT module successfully\n");
return 0;
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
