[PATCH v2 2/3] genhd, efi: add efi partition metadata to hd_structs

[Will Drewry <wad@chromium.org>]

This change extends the partition_meta_info structure to
support EFI GPT-specific metadata and ensures that data
is copied in on partition scanning.

Signed-off-by: Will Drewry <wad@chromium.org>

v2: move info assignment after memcpy()s
    adds _MAX to the enum after EFI
---
 fs/partitions/efi.c   |   16 ++++++++++++++++
 include/linux/genhd.h |   14 ++++++++++++++
 2 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/fs/partitions/efi.c b/fs/partitions/efi.c
index 9efb2cf..fac527d 100644
--- a/fs/partitions/efi.c
+++ b/fs/partitions/efi.c
@@ -614,6 +614,7 @@ int efi_partition(struct parsed_partitions *state)
 	pr_debug("GUID Partition Table is valid!  Yea!\n");
 
 	for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) {
+		struct partition_meta_info *info;
 		u64 start = le64_to_cpu(ptes[i].starting_lba);
 		u64 size = le64_to_cpu(ptes[i].ending_lba) -
 			   le64_to_cpu(ptes[i].starting_lba) + 1ULL;
@@ -627,6 +628,21 @@ int efi_partition(struct parsed_partitions *state)
 		if (!efi_guidcmp(ptes[i].partition_type_guid,
 				 PARTITION_LINUX_RAID_GUID))
 			state->parts[i + 1].flags = ADDPART_FLAG_RAID;
+
+		info = alloc_part_info(NULL);
+		if (!info) {
+			printk(KERN_WARNING
+			       "unable to allocate memory for part->info\n");
+			continue;
+		}
+		info->format = PARTITION_META_INFO_FORMAT_EFI;
+		memcpy(info->efi.uuid.b, ptes[i].unique_partition_guid.b,
+			sizeof(info->efi.uuid.b));
+		memcpy(info->efi.type.b, ptes[i].partition_type_guid.b,
+			sizeof(info->efi.type.b));
+		memcpy(info->efi.label, ptes[i].partition_name,
+			sizeof(info->efi.label));
+		state->parts[i + 1].info = info;
 	}
 	kfree(ptes);
 	kfree(gpt);
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 7b6644a..beb98e3 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -91,11 +91,25 @@ struct disk_stats {
 enum partition_meta_info_format_t {
 	/* Partition info format */
 	PARTITION_META_INFO_FORMAT_NONE = 0,
+	PARTITION_META_INFO_FORMAT_EFI,
+	/* Place additional formats here. */
+	PARTITION_META_INFO_FORMAT_MAX,
 };
 
+#ifdef CONFIG_EFI_PARTITION
+#include <linux/efi.h>
+#endif
+
 struct partition_meta_info {
 	enum partition_meta_info_format_t format;
 	union {
+#ifdef CONFIG_EFI_PARTITION
+		struct {
+			efi_guid_t uuid;
+			efi_guid_t type;
+			efi_char16_t label[72 / sizeof(efi_char16_t)];
+		} efi;
+#endif
 	};
 };
 
-- 
1.7.0.4