Implement boot device r/w functions for vboot

lib_generic/chromeos/boot_device.c

+/*
+ * Copyright 2010, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ */
+
+#include <config.h>
+#include <common.h>
+#include <part.h>
+#include <boot_device.h>
+
+static struct {
+        block_dev_desc_t *dev_desc;
+        ulong offset, limit;
+} bootdev_config = {
+        .dev_desc = NULL,
+        .offset = 0u,
+        .limit = 0u
+};
+
+block_dev_desc_t *get_bootdev(void)
+{
+        return bootdev_config.dev_desc;
+}
+
+int set_bootdev(char *ifname, int dev, int part)
+{
+        disk_partition_t part_info;
+
+        if ((bootdev_config.dev_desc = get_dev(ifname, dev)) == NULL)
+                goto cleanup; /* block device not supported */
+
+        /* largest address not available in block_dev_desc_t */
+        if (part == 0) {
+                bootdev_config.limit = ~0;
+                return 0;
+        }
+
+        if (get_partition_info(bootdev_config.dev_desc, part, &part_info))
+                goto cleanup; /* cannot find partition */
+
+        bootdev_config.offset = part_info.start;
+        bootdev_config.limit = part_info.size;
+
+        return 0;
+
+cleanup:
+        bootdev_config.dev_desc = NULL;
+        bootdev_config.offset = 0;
+        bootdev_config.limit = 0;
+
+        return 1;
+}
+
+int BootDeviceReadLBA(uint64_t lba_start, uint64_t lba_count, void *buffer)
+{
+        block_dev_desc_t *dev_desc;
+
+        if ((dev_desc = bootdev_config.dev_desc) == NULL)
+                return 1; /* No boot device configured */
+
+        if (lba_start + lba_count > bootdev_config.limit)
+                return 1; /* read out of range */
+
+        if (dev_desc->block_read(dev_desc->dev,
+                                bootdev_config.offset + lba_start, lba_count,
+                                buffer) < 0)
+                return 1; /* error reading blocks */
+
+        return 0;
+}
+
+int BootDeviceWriteLBA(uint64_t lba_start, uint64_t lba_count,
+                const void *buffer)
+{
+        block_dev_desc_t *dev_desc;
+
+        if ((dev_desc = bootdev_config.dev_desc) == NULL)
+                return 1; /* No boot device configured */
+
+        if (lba_start + lba_count > bootdev_config.limit)
+                return 1; /* read out of range */
+
+        if (dev_desc->block_write(dev_desc->dev,
+                                bootdev_config.offset + lba_start, lba_count,
+                                buffer) < 0)
+                return 1; /* error reading blocks */
+
+        return 0;
+}