disk: efi: unify code for finding a valid gpt

There were 3 copies of the same sequence, make it into a function.

Signed-off-by: Urja Rannikko <urjaman@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>

1 files changed, 34 insertions, 39 deletions

diff --git a/disk/part_efi.c b/disk/part_efi.c
index 359b55a818..3d9306235c 100644
--- a/disk/part_efi.c
+++ b/disk/part_efi.c
@@ -51,6 +51,8 @@ static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba,
 static gpt_entry *alloc_read_gpt_entries(struct blk_desc *dev_desc,
 					 gpt_header *pgpt_head);
 static int is_pte_valid(gpt_entry * pte);
+static int find_valid_gpt(struct blk_desc *dev_desc, gpt_header *gpt_head,
+			  gpt_entry **pgpt_pte);
 
 static char *print_efiname(gpt_entry *pte)
 {
@@ -192,19 +194,8 @@ int get_disk_guid(struct blk_desc * dev_desc, char *guid)
 	unsigned char *guid_bin;
 
 	/* This function validates AND fills in the GPT header and PTE */
-	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
-			 gpt_head, &gpt_pte) != 1) {
-		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
-		if (is_gpt_valid(dev_desc, dev_desc->lba - 1,
-				 gpt_head, &gpt_pte) != 1) {
-			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
-			       __func__);
-			return -EINVAL;
-		} else {
-			printf("%s: ***        Using Backup GPT ***\n",
-			       __func__);
-		}
-	}
+	if (find_valid_gpt(dev_desc, gpt_head, &gpt_pte) != 1)
+		return -EINVAL;
 
 	guid_bin = gpt_head->disk_guid.b;
 	uuid_bin_to_str(guid_bin, guid, UUID_STR_FORMAT_GUID);
@@ -223,19 +214,8 @@ void part_print_efi(struct blk_desc *dev_desc)
 	unsigned char *uuid_bin;
 
 	/* This function validates AND fills in the GPT header and PTE */
-	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
-			 gpt_head, &gpt_pte) != 1) {
-		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
-		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
-				 gpt_head, &gpt_pte) != 1) {
-			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
-			       __func__);
-			return;
-		} else {
-			printf("%s: ***        Using Backup GPT ***\n",
-			       __func__);
-		}
-	}
+	if (find_valid_gpt(dev_desc, gpt_head, &gpt_pte) != 1)
+		return;
 
 	debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
 
@@ -284,19 +264,8 @@ int part_get_info_efi(struct blk_desc *dev_desc, int part,
 	}
 
 	/* This function validates AND fills in the GPT header and PTE */
-	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
-			gpt_head, &gpt_pte) != 1) {
-		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
-		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
-				 gpt_head, &gpt_pte) != 1) {
-			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
-			       __func__);
-			return -1;
-		} else {
-			printf("%s: ***        Using Backup GPT ***\n",
-			       __func__);
-		}
-	}
+	if (find_valid_gpt(dev_desc, gpt_head, &gpt_pte) != 1)
+		return -1;
 
 	if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
 	    !is_pte_valid(&gpt_pte[part - 1])) {
@@ -997,6 +966,32 @@ static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba,
 }
 
 /**
+ * find_valid_gpt() - finds a valid GPT header and PTEs
+ *
+ * gpt is a GPT header ptr, filled on return.
+ * ptes is a PTEs ptr, filled on return.
+ *
+ * Description: returns 1 if found a valid gpt,  0 on error.
+ * If valid, returns pointers to PTEs.
+ */
+static int find_valid_gpt(struct blk_desc *dev_desc, gpt_header *gpt_head,
+			  gpt_entry **pgpt_pte)
+{
+	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
+			 gpt_head, pgpt_pte) != 1) {
+		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
+		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
+				 gpt_head, pgpt_pte) != 1) {
+			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
+			       __func__);
+			return 0;
+		}
+		printf("%s: ***        Using Backup GPT ***\n",  __func__);
+	}
+	return 1;
+}
+
+/**
  * alloc_read_gpt_entries(): reads partition entries from disk
  * @dev_desc
  * @gpt - GPT header