zdev: Add support for reading firmware configuration files

Add support for reading firmware-provided I/O configuration data files.
Such configuration files are generated by the Dynamic Partition Manager
and made available via a kernel interface for consumption by Linux.

To read a firmware configuration file, use the existing --import option:

 # chzdev --import /sys/firmware/sclp_sd/config/data

This will apply all I/O configuration data found in the specified file
to the persistent configuration.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

zdev/include/firmware.h

@@ -0,0 +1,25 @@
+/*
+ * zdev - Modify and display the persistent configuration of devices
+ *
+ * Copyright IBM Corp. 2017
+ *
+ * s390-tools is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+ */
+
+#ifndef FIRMWARE_H
+#define FIRMWARE_H
+
+#include <stdio.h>
+#include <stdbool.h>
+
+#include "exit_code.h"
+#include "misc.h"
+
+struct util_list;
+
+bool firmware_detect(FILE *fd);
+exit_code_t firmware_read(FILE *fd, const char *filename, long skip,
+			  config_t config, struct util_list *objects);
+
+#endif /* FIRMWARE_H */

zdev/man/chzdev.8

@@ -409,13 +409,23 @@ default value.
 .PP
 .
 .OD import "" "FILENAME" "|-"
-Import configuration data from a text file.
+Import configuration data from a text or machine-provided file.
 
 Reads configuration data from FILENAME and applies it. If a single hyphen ("-")
 is specified as FILENAME data is read from the standard input stream. The
-input format of the data read must be the same format as produced by the
-chzdev \-\-export action.
+input format must be either in the format as produced by the chzdev \-\-export
+action, or in the format of a machine-provided I/O configuration data file.
 
+.B Machine-provided data:
+Some machine models provide I/O configuration data which is made available
+by the Linux kernel via a sysfs interface. While this data is intended for
+automatic consumption during the boot phase, you can also apply it manually
+using the \-\-import action like in the following example
+
+.B Example:
+.CL chzdev --import /sys/firmware/sclp_sd/config/data
+
+.B Note:
 By default all configuration data that is read is also applied. To reduce the
 scope of imported configuration data, you can select specific devices, a device
 type, or define whether only data for the active or persistent configuration

zdev/src/Makefile

@@ -8,7 +8,7 @@ ALL_CPPFLAGS += -I ../include -std=gnu99 -Wno-unused-parameter \
 chzdev_objects += attrib.o chzdev.o device.o devnode.o devtype.o exit_code.o \
 		  export.o hash.o inuse.o misc.o namespace.o opts.o path.o \
 		  root.o select.o setting.o subtype.o table.o table_attribs.o \
-		  table_types.o net.o
+		  table_types.o net.o firmware.o
 
 # Devtype Helpers
 chzdev_objects += blkinfo.o ccw.o ccwgroup.o findmnt.o modprobe.o module.o \

zdev/src/chzdev.c

@@ -27,6 +27,7 @@
 #include "devnode.h"
 #include "devtype.h"
 #include "export.h"
+#include "firmware.h"
 #include "inuse.h"
 #include "misc.h"
 #include "module.h"
@@ -2500,9 +2501,9 @@ static exit_code_t do_export(struct options *opts)
 	/* Open output stream. */
 	if (strcmp(opts->export, "-") == 0) {
 		fd = stdout;
-		info("Exporting configuration data to standard output\n");
+		info("Exporting data to standard output\n");
 	} else {
-		info("Exporting configuration data to %s\n", opts->export);
+		info("Exporting data to %s\n", opts->export);
 		if (!util_path_exists(opts->export)) {
 			rc = path_create(opts->export);
 			if (rc)
@@ -2735,6 +2736,7 @@ static exit_code_t do_import(struct options *opts)
 	exit_code_t drc = EXIT_OK;
 	const char *filename;
 	int found;
+	bool is_firmware;
 
 	/* Open input stream. */
 	if (strcmp(opts->import, "-") == 0) {
@@ -2744,16 +2746,23 @@ static exit_code_t do_import(struct options *opts)
 		fd = fopen(opts->import, "r");
 		filename = opts->import;
 	}
-	info("Importing configuration data from %s\n", filename);
+
 	if (!fd) {
 		error("Could not open file %s: %s\n", opts->import,
 		      strerror(errno));
 		return EXIT_RUNTIME_ERROR;
 	}
 
+	is_firmware = firmware_detect(fd);
+	info("Importing data from %s%s\n", filename,
+	     is_firmware ? " (firmware format)" : "");
+
 	/* Read data. */
 	objects = ptrlist_new();
-	rc = export_read(fd, filename, objects);
+	if (is_firmware)
+		rc = firmware_read(fd, filename, -1, opts->config, objects);
+	else
+		rc = export_read(fd, filename, objects);
 	if (rc)
 		goto out;
 
@@ -2766,8 +2775,8 @@ static exit_code_t do_import(struct options *opts)
 			      "selection\n", filename);
 			rc = EXIT_EMPTY_SELECTION;
 		} else {
-			error("%s: No settings found to import\n", filename);
-			rc = EXIT_NO_DATA;
+			info("%s: No settings found to import\n", filename);
+			rc = EXIT_OK;
 		}
 		goto out;
 	}

zdev/src/firmware.c

@@ -0,0 +1,676 @@
+/*
+ * zdev - Modify and display the persistent configuration of devices
+ *
+ * Copyright IBM Corp. 2017
+ *
+ * s390-tools is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+ */
+
+#include <err.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "attrib.h"
+#include "ccw.h"
+#include "ccwgroup.h"
+#include "dasd.h"
+#include "device.h"
+#include "export.h"
+#include "firmware.h"
+#include "misc.h"
+#include "qeth.h"
+#include "subtype.h"
+#include "zfcp_host.h"
+#include "zfcp_lun.h"
+
+/* In-memory firmware file representation. */
+struct fw_file {
+	const char *name;
+	char *buffer;
+	size_t size;
+	char *last_access;
+	size_t last_size;
+};
+
+/* Record access to fields of the buffered file for use in warning messages. */
+#define fwacc(f, x)	((f)->last_access = (char *) &(x), \
+			 (f)->last_size = sizeof(x), x)
+
+/*
+ * Firmware file format definitions.
+ */
+
+/* Firmware file header. */
+struct fw_filehdr {
+	uint32_t magic;
+	uint16_t ver;
+	uint16_t hdr_len;
+	uint32_t file_len;
+	uint32_t seq;
+	uint32_t zeroes;
+	uint16_t de_count;
+	char unused[10];
+} __packed;
+
+#define FW_HDR_MAGIC		0x7a646576	/* ASCII "zdev" */
+#define FW_HDR_VER_Z14		0x0000
+
+/* I/O device ID. */
+struct fw_iodevid {
+	uint8_t cssid;
+	uint8_t ssid;
+	uint16_t devno;
+} __packed;
+
+#define FW_IODEVID_FLAG_MCSS	0x01
+
+/* Device setting. */
+struct fw_setting {
+	uint16_t len;
+	uint8_t key_type;
+	uint8_t key_len;
+	uint8_t val_type;
+	uint8_t val_len;
+	char data[];
+} __packed;
+
+#define FW_SETTING_KEYTYPE_ASCII	0x00
+#define FW_SETTING_VALTYPE_ASCII	0x00
+#define FW_SETTING_VALTYPE_UINT		0x01
+
+/* Device settings list. */
+struct fw_setlist {
+	uint16_t len;
+	char data[];
+} __packed;
+
+/* Device entry header. */
+struct fw_dehdr {
+	uint16_t type;
+	uint16_t len;
+	uint32_t seq;
+} __packed;
+
+#define FW_DE_HDR_TYPE_DASD		0x0001
+#define FW_DE_HDR_TYPE_ZFCP_HOST	0x0002
+#define FW_DE_HDR_TYPE_ZFCP_LUN		0x0003
+#define FW_DE_HDR_TYPE_QETH		0x0004
+
+/* DASD device entry. */
+struct fw_dasd {
+	struct fw_dehdr hdr;
+	uint8_t id_flags;
+	struct fw_iodevid id;
+	char settings[];
+} __packed;
+
+/* zFCP host device entry. */
+struct fw_zfcp_host {
+	struct fw_dehdr hdr;
+	uint8_t id_flags;
+	struct fw_iodevid id;
+	char settings[];
+} __packed;
+
+/* zFCP LUN device entry. */
+struct fw_zfcp_lun {
+	struct fw_dehdr hdr;
+	uint8_t id_flags;
+	struct fw_iodevid id;
+	uint64_t wwpn;
+	uint64_t fcp_lun;
+	char settings[];
+} __packed;
+
+/* QETH device entry. */
+struct fw_qeth {
+	struct fw_dehdr hdr;
+	uint8_t id_flags;
+	struct fw_iodevid read_id;
+	struct fw_iodevid write_id;
+	struct fw_iodevid data_id;
+	char settings[];
+} __packed;
+
+/* Emit a warning that refers to a position in a firmware file. */
+static void fwwarn(struct fw_file *f, const char *fmt, ...)
+{
+	va_list args;
+	off_t start = (off_t) (f->last_access - f->buffer),
+	      end = start + f->last_size - 1;
+
+	fprintf(stderr, "%s: ", f->name);
+	if (start == end)
+		fprintf(stderr, "Byte 0x%zx: ", start);
+	else
+		fprintf(stderr, "Bytes 0x%zx-0x%zx: ", start, end);
+
+	va_start(args, fmt);
+	vfprintf(stderr, fmt, args);
+	va_end(args);
+	fprintf(stderr, "\n");
+}
+
+/* Basic file format header sanity check. */
+static bool check_header(struct fw_file *f, struct fw_filehdr *hdr)
+{
+	if (fwacc(f, hdr->magic) != FW_HDR_MAGIC)
+		fwwarn(f, "Invalid file magic (0x%08x)", hdr->magic);
+	else if (fwacc(f, hdr->ver) != FW_HDR_VER_Z14)
+		fwwarn(f, "Unsupported file version (0x%04x)", hdr->ver);
+	else
+		return true;
+
+	return false;
+}
+
+#define READ_RETRY	3
+
+/* Read a firmware configuration file. */
+static exit_code_t read_fw(struct fw_file *file, FILE *fd, const char *filename)
+{
+	struct fw_file f = { NULL };
+	struct fw_filehdr *hdr;
+	char *buffer, *buffer2;
+	size_t size, size2;
+	int retry;
+	exit_code_t rc = EXIT_OK;
+
+	for (retry = 0; retry < READ_RETRY; retry++) {
+		/* Read complete file once */
+		rc = misc_read_fd(fd, (void **) &buffer, &size);
+		if (rc) {
+			warn("%s: Could not read file", filename);
+			return rc;
+		}
+		if (!buffer) {
+			/* Empty file - skip silently as this is the default
+			 * on machines without firmware support. */
+			return rc;
+		}
+
+		/* Re-read complete file to detect in-flight modifications. */
+		if (fseek(fd, 0, SEEK_SET) == -1) {
+			/* Could be a pipe, socket, or FIFO - accept v1. */
+			break;
+		}
+		rc = misc_read_fd(fd, (void **) &buffer2, &size2);
+		if (rc || !buffer2) {
+			/* Could not get second version - accept v1. */
+			break;
+		}
+
+		if (size == size2 && memcmp(buffer, buffer2, size) == 0) {
+			/* No change */
+			free(buffer2);
+			break;
+		}
+
+		free(buffer);
+		free(buffer2);
+	}
+
+	if (retry >= READ_RETRY) {
+		warnx("%s: File changed %d times while reading - aborting",
+		      filename, retry);
+		return EXIT_RUNTIME_ERROR;
+	}
+
+	/* Perform basic checks */
+	f.name = filename;
+	f.buffer = buffer;
+	f.size = size;
+	hdr = (void *) buffer;
+	if (!check_header(&f, hdr)) {
+		free(buffer);
+		return EXIT_FORMAT_ERROR;
+	}
+	if (fwacc(&f, hdr->file_len) > size) {
+		fwwarn(&f, "File length mismatch (expect %zu) - adjusting",
+		       size);
+		hdr->file_len = size;
+	}
+
+	*file = f;
+
+	return EXIT_OK;
+}
+
+/* Return textual representation of a device entry type. */
+static const char *type_to_str(uint16_t type)
+{
+	switch (type) {
+	case FW_DE_HDR_TYPE_DASD:
+		return "dasd";
+	case FW_DE_HDR_TYPE_ZFCP_HOST:
+		return "zfcp-host";
+	case FW_DE_HDR_TYPE_ZFCP_LUN:
+		return "zfcp-lun";
+	case FW_DE_HDR_TYPE_QETH:
+		return "qeth";
+	default:
+		return "<unknown>";
+	}
+}
+
+/* Convert a binary format device setting of the specified length to integer. */
+static unsigned long parse_value(char *data, uint8_t len)
+{
+	switch (len) {
+	case 1:
+		return (unsigned long) *((uint8_t *) data);
+	case 2:
+		return (unsigned long) *((uint16_t *) data);
+	case 4:
+		return (unsigned long) *((uint32_t *) data);
+	case 8:
+		return (unsigned long) *((uint64_t *) data);
+	default:
+		return 0;
+	}
+}
+
+/* Perform sanity checks on device setting. */
+static bool check_setting(struct fw_file *f, struct fw_setting *set)
+{
+	/* Key sanity checks */
+	if (fwacc(f, set->key_type) != FW_SETTING_KEYTYPE_ASCII) {
+		fwwarn(f, "Unsupported key type: %d", set->key_type);
+		return false;
+	}
+	if (fwacc(f, set->key_len) < 1) {
+		fwwarn(f, "Unsupported key length: %d", set->key_len);
+		return false;
+	}
+	if (sizeof(struct fw_setting) + fwacc(f, set->key_len) > set->len) {
+		fwwarn(f, "Key length exceeds setting");
+		return false;
+	}
+	if (fwacc(f, set->data[set->key_len - 1])) {
+		fwwarn(f, "Key not null-terminated");
+		return false;
+	}
+
+	/* Value sanity checks */
+	if (fwacc(f, set->val_type) != FW_SETTING_VALTYPE_UINT &&
+	    fwacc(f, set->val_type) != FW_SETTING_VALTYPE_ASCII) {
+		fwwarn(f, "Unsupported value type: %d", set->val_type);
+		return false;
+	}
+	if (fwacc(f, set->val_len) < 1) {
+		fwwarn(f, "Unsupported value length: %d", set->val_len);
+		return false;
+	}
+	if (sizeof(struct fw_setting) + set->key_len +
+	    fwacc(f, set->val_len) > set->len) {
+		fwwarn(f, "Value length exceeds setting");
+		return false;
+	}
+	if ((set->val_type == FW_SETTING_VALTYPE_ASCII) &&
+	    fwacc(f, set->data[set->key_len + set->val_len - 1])) {
+		fwwarn(f, "Value not null-terminated");
+		return false;
+	}
+	if (set->val_type == FW_SETTING_VALTYPE_UINT) {
+		switch (fwacc(f, set->val_len)) {
+		case 1:
+		case 2:
+		case 4:
+		case 8:
+			break;
+		default:
+			fwwarn(f, "Unsupported integer value length: %d",
+			       set->val_len);
+			return false;
+		}
+	}
+
+	return true;
+}
+
+/* Add a setting to the device. Emit a warning if the setting is not known. */
+static void _add_setting(const char *filename, struct device *dev,
+			 config_t config, const char *key, const char *value)
+{
+	struct attrib *a;
+	struct setting_list *list;
+
+	list = device_get_setting_list(dev, config);
+	a = attrib_find(dev->subtype->dev_attribs, key);
+	if (!a) {
+		warnx("%s: Applying unknown device setting %s=%s", filename,
+		      key, value);
+	}
+	setting_list_apply(list, a, key, value);
+}
+
+static void add_setting(const char *filename, struct device *dev,
+			config_t config, const char *key, const char *value)
+{
+	if (SCOPE_ACTIVE(config))
+		_add_setting(filename, dev, config_active, key, value);
+	if (SCOPE_PERSISTENT(config))
+		_add_setting(filename, dev, config_persistent, key, value);
+}
+
+/* Parse a single device setting in firmware format and apply it to the
+ * specified device. */
+static void parse_setting(struct fw_file *f, struct fw_setting *set,
+			  struct device *dev, config_t config)
+{
+	char *ascii_key, *ascii_val;
+	unsigned long ulong_val;
+
+	if (!check_setting(f, set))
+		return;
+
+	ascii_key = &set->data[0];
+	if (set->val_type == FW_SETTING_VALTYPE_UINT) {
+		ulong_val = parse_value(&set->data[set->key_len], set->val_len);
+		ascii_val = misc_asprintf("%lu", ulong_val);
+		add_setting(f->name, dev, config, ascii_key, ascii_val);
+		free(ascii_val);
+	} else {
+		ascii_val = &set->data[set->key_len];
+		add_setting(f->name, dev, config, ascii_key, ascii_val);
+	}
+}
+
+/* Parse a device settings list in firmware format and apply the resulting
+ * settings to the specified device. */
+static void parse_settings(struct fw_file *f, char *data, struct device *dev,
+			   config_t config)
+{
+	struct fw_setlist *list = (struct fw_setlist *) data;
+	struct fw_setting *set;
+	uint16_t off;
+
+	for (off = sizeof(struct fw_setlist); off < list->len;
+	     off += set->len) {
+		set = (struct fw_setting *) &data[off];
+		if (fwacc(f, set->len) < sizeof(struct fw_setting)) {
+			fwwarn(f, "Setting too short");
+			break;
+		}
+		if (off + fwacc(f, set->len) > list->len) {
+			fwwarn(f, "Setting too long");
+			break;
+		}
+		parse_setting(f, set, dev, config);
+	}
+}
+
+/* Perform sanity checks on an I/O device ID. */
+static bool check_iodevid(struct fw_file *f, uint8_t *flags,
+			  struct fw_iodevid *id)
+{
+
+	if (fwacc(f, *flags) & FW_IODEVID_FLAG_MCSS) {
+		fwwarn(f, "Unsupported entry in non-default CSS");
+		return false;
+	}
+	if (fwacc(f, id->cssid) != 0) {
+		fwwarn(f, "Non-zero CSS-ID");
+		return false;
+	}
+	return true;
+}
+
+/* Perform sanity checks on a device entry. */
+static bool check_de_size(struct fw_file *f, struct fw_dehdr *de, size_t size)
+{
+	if (fwacc(f, de->len) < size) {
+		fwwarn(f, "Device entry too short (expect %zu)", size);
+		return false;
+	}
+	return true;
+}
+
+/* Convert an I/O device ID to CCW device ID format. */
+static void io_to_ccw(struct ccw_devid *c, struct fw_iodevid *i)
+{
+	c->cssid = i->cssid;
+	c->ssid = i->ssid;
+	c->devno = i->devno;
+}
+
+/* Register a new device configuration. */
+static struct device *add_device(struct fw_file *f, struct subtype *st,
+				 const char *id, config_t config,
+				 struct util_list *objects)
+{
+	struct device *dev;
+
+	if (!st->devices)
+		st->devices = device_list_new(st);
+
+	dev = device_list_find(st->devices, id, NULL);
+	if (!dev) {
+		dev = device_new(st, id);
+		if (!dev) {
+			warnx("%s: Skipping invalid %s device ID %s", f->name,
+			      st->name, id);
+			return NULL;
+		}
+		device_list_add(st->devices, dev);
+	}
+	ptrlist_add(objects, object_new(export_device, dev));
+
+	/* Prepare device for new settings. */
+	if (SCOPE_ACTIVE(config)) {
+		setting_list_clear(dev->active.settings);
+		if (dev->subtype->support_definable)
+			dev->active.definable = 1;
+		else
+			dev->active.exists = 1;
+	}
+	if (SCOPE_PERSISTENT(config)) {
+		setting_list_clear(dev->persistent.settings);
+		dev->persistent.exists = 1;
+	}
+
+	return dev;
+}
+
+/* Parse a DASD device entry. */
+static void parse_dasd(struct fw_file *f, struct fw_dehdr *de, config_t config,
+		       struct util_list *objects)
+{
+	struct fw_dasd *dasd = (struct fw_dasd *) de;
+	struct ccw_devid devid;
+	struct device *dev_eckd, *dev_fba;
+	char *id;
+
+	if (!check_de_size(f, de, sizeof(struct fw_dasd)))
+		return;
+	if (!check_iodevid(f, &dasd->id_flags, &dasd->id))
+		return;
+
+	/* Could be either dasd_eckd or dasd_fba - add both entries */
+	io_to_ccw(&devid, &dasd->id);
+	id = ccw_devid_to_str(&devid);
+	dev_eckd = add_device(f, &dasd_subtype_eckd, id, config, objects);
+	dev_fba = add_device(f, &dasd_subtype_fba, id, config, objects);
+	free(id);
+
+	if (dasd->hdr.len > sizeof(struct fw_dasd)) {
+		if (dev_eckd)
+			parse_settings(f, dasd->settings, dev_eckd, config);
+		if (dev_fba)
+			parse_settings(f, dasd->settings, dev_fba, config);
+	}
+}
+
+/* Parse a zFCP host device entry. */
+static void parse_zfcp_host(struct fw_file *f, struct fw_dehdr *de,
+			    config_t config, struct util_list *objects)
+{
+	struct fw_zfcp_host *zfcp_host = (struct fw_zfcp_host *) de;
+	struct ccw_devid devid;
+	struct device *dev;
+	char *id;
+
+	if (!check_de_size(f, de, sizeof(struct fw_zfcp_host)))
+		return;
+	if (!check_iodevid(f, &zfcp_host->id_flags, &zfcp_host->id))
+		return;
+
+	/* Add zfcp_host entry */
+	io_to_ccw(&devid, &zfcp_host->id);
+	id = ccw_devid_to_str(&devid);
+	dev = add_device(f, &zfcp_host_subtype, id, config, objects);
+	free(id);
+
+	if (dev && zfcp_host->hdr.len > sizeof(struct fw_zfcp_host))
+		parse_settings(f, zfcp_host->settings, dev, config);
+}
+
+/* Parse a zFCP LUN device entry. */
+static void parse_zfcp_lun(struct fw_file *f, struct fw_dehdr *de,
+			   config_t config, struct util_list *objects)
+{
+	struct fw_zfcp_lun *zfcp_lun = (struct fw_zfcp_lun *) de;
+	struct zfcp_lun_devid devid;
+	struct device *dev;
+	char *id;
+
+	if (!check_de_size(f, de, sizeof(struct fw_zfcp_lun)))
+		return;
+	if (!check_iodevid(f, &zfcp_lun->id_flags, &zfcp_lun->id))
+		return;
+
+	/* Add zfcp_lun entry */
+	io_to_ccw(&devid.fcp_dev, &zfcp_lun->id);
+	devid.wwpn = zfcp_lun->wwpn;
+	devid.lun = zfcp_lun->fcp_lun;
+	id = zfcp_lun_devid_to_str(&devid);
+	dev = add_device(f, &zfcp_lun_subtype, id, config, objects);
+	free(id);
+
+	if (dev && zfcp_lun->hdr.len > sizeof(struct fw_zfcp_lun))
+		parse_settings(f, zfcp_lun->settings, dev, config);
+
+}
+
+/* Parse a QETH device entry. */
+static void parse_qeth(struct fw_file *f, struct fw_dehdr *de, config_t config,
+		       struct util_list *objects)
+{
+	struct fw_qeth *qeth = (struct fw_qeth *) de;
+	struct ccwgroup_devid devid;
+	struct device *dev;
+	char *id;
+
+	if (!check_de_size(f, de, sizeof(struct fw_qeth)))
+		return;
+	if (!check_iodevid(f, &qeth->id_flags, &qeth->read_id) ||
+	    !check_iodevid(f, &qeth->id_flags, &qeth->write_id) ||
+	    !check_iodevid(f, &qeth->id_flags, &qeth->data_id))
+		return;
+
+	/* Add qeth entry */
+	devid.num = 3;
+	io_to_ccw(&devid.devid[0], &qeth->read_id);
+	io_to_ccw(&devid.devid[1], &qeth->write_id);
+	io_to_ccw(&devid.devid[2], &qeth->data_id);
+	id = ccwgroup_devid_to_str(&devid);
+	dev = add_device(f, &qeth_subtype_qeth, id, config, objects);
+	free(id);
+
+	if (dev && qeth->hdr.len > sizeof(struct fw_qeth))
+		parse_settings(f, qeth->settings, dev, config);
+}
+
+/* Parse a firmware file. */
+static void parse_fw(struct fw_file *f, long skip, config_t config,
+		     struct util_list *objects)
+{
+	char *data = f->buffer;
+	struct fw_filehdr *hdr = (struct fw_filehdr *) data;
+	struct fw_dehdr *de;
+	uint16_t count = 0;
+	uint32_t off;
+
+	for (off = hdr->hdr_len; off < hdr->file_len; off += de->len) {
+		count++;
+		de = (struct fw_dehdr *) &data[off];
+		if (fwacc(f, de->len) == 0) {
+			fwwarn(f, "Empty device entry");
+			break;
+		}
+		if (off + fwacc(f, de->len) > hdr->file_len) {
+			fwwarn(f, "Device entry too long");
+			break;
+		}
+		if (skip >= 0 && de->seq <= skip) {
+			debug("Skipping %s entry due to sequence (%08x)\n",
+			      type_to_str(de->type), de->seq);
+			continue;
+		}
+		switch (fwacc(f, de->type)) {
+		case FW_DE_HDR_TYPE_DASD:
+			parse_dasd(f, de, config, objects);
+			break;
+		case FW_DE_HDR_TYPE_ZFCP_HOST:
+			parse_zfcp_host(f, de, config, objects);
+			break;
+		case FW_DE_HDR_TYPE_ZFCP_LUN:
+			parse_zfcp_lun(f, de, config, objects);
+			break;
+		case FW_DE_HDR_TYPE_QETH:
+			parse_qeth(f, de, config, objects);
+			break;
+		default:
+			fwwarn(f, "Unknown entry (type=%04x)", de->type);
+			break;
+		}
+	}
+
+	if (count != fwacc(f, hdr->de_count))
+		fwwarn(f, "Device entry count mismatch");
+}
+
+/* Read configuration objects from @fd in firmware file format. Add pointers to
+ * newly allocated struct export_objects to ptrlist @objects. If @skip is a
+ * positive number, skip over entries with a sequence number equal to or
+ * greater than @skip. */
+exit_code_t firmware_read(FILE *fd, const char *filename, long skip,
+			  config_t config, struct util_list *objects)
+{
+	struct fw_file file;
+	exit_code_t rc;
+
+	rc = read_fw(&file, fd, filename);
+	if (rc)
+		return rc;
+
+	parse_fw(&file, skip, config, objects);
+	free(file.buffer);
+
+	return rc;
+}
+
+/* Check if @fd refers to a file in binary firmware format. */
+bool firmware_detect(FILE *fd)
+{
+	int c;
+
+	c = fgetc(fd);
+	ungetc(c, fd);
+
+	/* Note: A full check would require looking at least at the first 4
+	 * bytes, but fd might be non-seekable (e.g. pipe). Since there is no
+	 * way that a textual import file can start with a 'z', looking at
+	 * the first char should be enough. */
+
+	return c == 'z';
+}