From: Russ Weight <russell.h.weight@xxxxxxxxx>
Extend the FPGA 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@xxxxxxxxx>
Reviewed-by: Tom Rix <trix@xxxxxxxxxx>
Signed-off-by: Moritz Fischer <mdf@xxxxxxxxxx>
---
.../ABI/testing/sysfs-class-fpga-sec-mgr | 11 +++++
drivers/fpga/fpga-sec-mgr.c | 42 +++++++++++++++++--
2 files changed, 49 insertions(+), 4 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr b/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr
index 36d1b6ba8d76..b962ad2cf18d 100644
--- a/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr
+++ b/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr
@@ -16,3 +16,14 @@ Description: Write only. Write the filename of an image
BMC images, BMC firmware, Static Region images,
and Root Entry Hashes, and to cancel Code Signing
Keys (CSK).
+
+What: /sys/class/fpga_sec_mgr/fpga_secX/update/status
+Date: June 2021
+KernelVersion: 5.14
+Contact: Russ Weight <russell.h.weight@xxxxxxxxx>
+Description: Read-only. Returns a string describing the current
+ status of an update. The string will be one of the
+ following: idle, reading, 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/fpga-sec-mgr.c b/drivers/fpga/fpga-sec-mgr.c
index bfdb01d2de57..19f60048a965 100644
--- a/drivers/fpga/fpga-sec-mgr.c
+++ b/drivers/fpga/fpga-sec-mgr.c
@@ -23,6 +23,13 @@ struct fpga_sec_mgr_devres {
#define to_sec_mgr(d) container_of(d, struct fpga_sec_mgr, dev)
+static void update_progress(struct fpga_sec_mgr *smgr,
+ enum fpga_sec_prog new_progress)
+{
+ smgr->progress = new_progress;
+ sysfs_notify(&smgr->dev.kobj, "update", "status");
+}
+
static void fpga_sec_dev_error(struct fpga_sec_mgr *smgr,
enum fpga_sec_err err_code)
{
@@ -33,7 +40,7 @@ static void fpga_sec_dev_error(struct fpga_sec_mgr *smgr,
static void progress_complete(struct fpga_sec_mgr *smgr)
{
mutex_lock(&smgr->lock);
- smgr->progress = FPGA_SEC_PROG_IDLE;
+ update_progress(smgr, FPGA_SEC_PROG_IDLE);
complete_all(&smgr->update_done);
mutex_unlock(&smgr->lock);
}
@@ -61,14 +68,14 @@ static void fpga_sec_mgr_update(struct work_struct *work)
goto release_fw_exit;
}
- smgr->progress = FPGA_SEC_PROG_PREPARING;
+ update_progress(smgr, FPGA_SEC_PROG_PREPARING);
ret = smgr->sops->prepare(smgr);
if (ret != FPGA_SEC_ERR_NONE) {
fpga_sec_dev_error(smgr, ret);
goto modput_exit;
}
- smgr->progress = FPGA_SEC_PROG_WRITING;
+ update_progress(smgr, FPGA_SEC_PROG_WRITING);
while (smgr->remaining_size) {
ret = smgr->sops->write_blk(smgr, offset);
if (ret != FPGA_SEC_ERR_NONE) {
@@ -79,7 +86,7 @@ static void fpga_sec_mgr_update(struct work_struct *work)
offset = fw->size - smgr->remaining_size;
}
- smgr->progress = FPGA_SEC_PROG_PROGRAMMING;
+ update_progress(smgr, FPGA_SEC_PROG_PROGRAMMING);
ret = smgr->sops->poll_complete(smgr);
if (ret != FPGA_SEC_ERR_NONE)
fpga_sec_dev_error(smgr, ret);
@@ -107,6 +114,32 @@ static void fpga_sec_mgr_update(struct work_struct *work)
progress_complete(smgr);
}
+static const char * const sec_mgr_prog_str[] = {
+ [FPGA_SEC_PROG_IDLE] = "idle",
+ [FPGA_SEC_PROG_READING] = "reading",
+ [FPGA_SEC_PROG_PREPARING] = "preparing",
+ [FPGA_SEC_PROG_WRITING] = "writing",
+ [FPGA_SEC_PROG_PROGRAMMING] = "programming"
+};
+
+static ssize_t
+status_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct fpga_sec_mgr *smgr = to_sec_mgr(dev);
+ const char *status = "unknown-status";
+ enum fpga_sec_prog progress;
+
+ progress = smgr->progress;
+ if (progress < FPGA_SEC_PROG_MAX)
+ status = sec_mgr_prog_str[progress];
+ else
+ dev_err(dev, "Invalid status during secure update: %d\n",
+ progress);
+
+ return sysfs_emit(buf, "%s\n", status);
+}
+static DEVICE_ATTR_RO(status);
+
static ssize_t filename_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
@@ -141,6 +174,7 @@ static DEVICE_ATTR_WO(filename);
static struct attribute *sec_mgr_update_attrs[] = {
&dev_attr_filename.attr,
+ &dev_attr_status.attr,
NULL,
};
--
2.31.1
