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> --- v14: - Updated ABI documentation date and kernel version v13: - No change v12: - Updated Date and KernelVersion fields in ABI documentation - Changed syntax of sec_mgr_prog_str[] array definition from: "idle", /* FPGA_SEC_PROG_IDLE */ to: [FPGA_SEC_PROG_IDLE] = "idle", v11: - No change v10: - Rebased to 5.12-rc2 next - Updated Date and KernelVersion in ABI documentation v9: - Updated Date and KernelVersion in ABI documentation v8: - No change v7: - Changed Date in documentation file to December 2020 v6: - No change v5: - Use new function sysfs_emit() in the status_show() function v4: - Changed from "Intel FPGA Security Manager" to FPGA Security Manager" and removed unnecessary references to "Intel". - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_ v3: - Use a local variable to read progress once in status_show() - Use dev_err to report invalid progress status v2: - Bumped documentation date and version - Changed progress state "read_file" to "reading" --- .../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 278eff1389df..e62cb12d41d4 100644 --- a/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr +++ b/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr @@ -10,3 +10,14 @@ 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: Aug 2021 +KernelVersion: 5.15 +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 487a04f75657..436c00e4cd0f 100644 --- a/drivers/fpga/fpga-sec-mgr.c +++ b/drivers/fpga/fpga-sec-mgr.c @@ -20,6 +20,13 @@ static struct class *fpga_sec_mgr_class; #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) { @@ -30,7 +37,7 @@ 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); } @@ -58,14 +65,14 @@ 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) { @@ -76,7 +83,7 @@ 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); @@ -104,6 +111,32 @@ 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) { @@ -138,6 +171,7 @@ static DEVICE_ATTR_WO(filename); static struct attribute *sec_mgr_update_attrs[] = { &dev_attr_filename.attr, + &dev_attr_status.attr, NULL, }; -- 2.25.1