[PATCH v1 07/12] fpga: expose sec-mgr update status

Russ Weight
2020-09-04T23:53:58Z

Extend the Intel Security Manager class driver to
include an update/status sysfs node that can be polled
and read to monitor the progress of an ongoing secure
update. Sysfs_notify() is used to signal transitions
between different phases of the update process.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Wu Hao <hao.wu@intel.com>
---
.../ABI/testing/sysfs-class-ifpga-sec-mgr | 11 ++++++
drivers/fpga/ifpga-sec-mgr.c | 34 ++++++++++++++++---
2 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr b/Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr
index a476504b7ae9..849ccb2802f8 100644
--- a/Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr
+++ b/Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr
@@ -86,3 +86,14 @@ Description: Write only. Write the filename of an Intel image
BMC images, BMC firmware, Static Region images,
and Root Entry Hashes, and to cancel Code Signing
Keys (CSK).
+
+What: /sys/class/ifpga_sec_mgr/ifpga_secX/update/status
+Date: Sep 2020
+KernelVersion: 5.10
+Contact: Russ Weight <russell.h.weight@intel.com>
+Description: Read-only. Returns a string describing the current
+ status of an update. The string will be one of the
+ following: idle, read_file, preparing, writing,
+ programming. Userspace code can poll on this file,
+ as it will be signaled by sysfs_notify() on each
+ state change.
diff --git a/drivers/fpga/ifpga-sec-mgr.c b/drivers/fpga/ifpga-sec-mgr.c
index 73173badbe96..5fe3d85e2963 100644
--- a/drivers/fpga/ifpga-sec-mgr.c
+++ b/drivers/fpga/ifpga-sec-mgr.c
@@ -139,6 +139,13 @@ static struct attribute *sec_mgr_security_attrs[] = {
NULL,
};

+static void update_progress(struct ifpga_sec_mgr *imgr,
+ enum ifpga_sec_prog new_progress)
+{
+ imgr->progress = new_progress;
+ sysfs_notify(&imgr->dev.kobj, "update", "status");
+}
+
static void ifpga_sec_dev_error(struct ifpga_sec_mgr *imgr,
enum ifpga_sec_err err_code)
{
@@ -149,7 +156,7 @@ static void ifpga_sec_dev_error(struct ifpga_sec_mgr *imgr,
static void progress_complete(struct ifpga_sec_mgr *imgr)
{
mutex_lock(&imgr->lock);
- imgr->progress = IFPGA_SEC_PROG_IDLE;
+ update_progress(imgr, IFPGA_SEC_PROG_IDLE);
complete_all(&imgr->update_done);
mutex_unlock(&imgr->lock);
}
@@ -177,14 +184,14 @@ static void ifpga_sec_mgr_update(struct work_struct *work)
goto release_fw_exit;
}

- imgr->progress = IFPGA_SEC_PROG_PREPARING;
+ update_progress(imgr, IFPGA_SEC_PROG_PREPARING);
ret = imgr->iops->prepare(imgr);
if (ret) {
ifpga_sec_dev_error(imgr, ret);
goto modput_exit;
}

- imgr->progress = IFPGA_SEC_PROG_WRITING;
+ update_progress(imgr, IFPGA_SEC_PROG_WRITING);
size = imgr->remaining_size;
while (size) {
blk_size = min_t(u32, size, WRITE_BLOCK_SIZE);
@@ -199,7 +206,7 @@ static void ifpga_sec_mgr_update(struct work_struct *work)
offset += blk_size;
}

- imgr->progress = IFPGA_SEC_PROG_PROGRAMMING;
+ update_progress(imgr, IFPGA_SEC_PROG_PROGRAMMING);
ret = imgr->iops->poll_complete(imgr);
if (ret) {
ifpga_sec_dev_error(imgr, ret);
@@ -251,6 +258,24 @@ static struct attribute_group sec_mgr_security_attr_group = {
.is_visible = sec_mgr_visible,
};

+static const char * const sec_mgr_prog_str[] = {
+ "idle", /* IFPGA_SEC_PROG_IDLE */
+ "read_file", /* IFPGA_SEC_PROG_READ_FILE */
+ "preparing", /* IFPGA_SEC_PROG_PREPARING */
+ "writing", /* IFPGA_SEC_PROG_WRITING */
+ "programming" /* IFPGA_SEC_PROG_PROGRAMMING */
+};
+
+static ssize_t
+status_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct ifpga_sec_mgr *imgr = to_sec_mgr(dev);
+
+ return sprintf(buf, "%s\n", (imgr->progress < IFPGA_SEC_PROG_MAX) ?
+ sec_mgr_prog_str[imgr->progress] : "unknown-status");
+}
+static DEVICE_ATTR_RO(status);
+
static ssize_t filename_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
@@ -288,6 +313,7 @@ static DEVICE_ATTR_WO(filename);

static struct attribute *sec_mgr_update_attrs[] = {
&dev_attr_filename.attr,
+ &dev_attr_status.attr,
NULL,
};

--
2.17.1