btrfs-progs: merge device id comparators

There are two similar but slightly different implementations of devid
comparison functions: cmp_device_id() in filesystem.c and _cmp_device_by_id()
in mkfs/main.c. Merge them as cmp_device_id in common/device-utils.c.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Author: asj

cmds/filesystem.c

@@ -259,21 +259,6 @@ static int uuid_search(struct btrfs_fs_devices *fs_devices, const char *search)
 	return 0;
 }
 
-/*
- * Sort devices by devid, ascending
- */
-static int cmp_device_id(void *priv, struct list_head *a,
-		struct list_head *b)
-{
-	const struct btrfs_device *da = list_entry(a, struct btrfs_device,
-			dev_list);
-	const struct btrfs_device *db = list_entry(b, struct btrfs_device,
-			dev_list);
-
-	return da->devid < db->devid ? -1 :
-		da->devid > db->devid ? 1 : 0;
-}
-
 static void splice_device_list(struct list_head *seed_devices,
 			       struct list_head *all_devices)
 {

common/device-utils.c

@@ -641,3 +641,15 @@ ssize_t btrfs_direct_pwrite(int fd, const void *buf, size_t count, off_t offset)
 	free(bounce_buf);
 	return ret;
 }
+
+/* Sort devices by devid, ascending */
+int cmp_device_id(void *priv, struct list_head *a, struct list_head *b)
+{
+	const struct btrfs_device *da = list_entry(a, struct btrfs_device,
+			dev_list);
+	const struct btrfs_device *db = list_entry(b, struct btrfs_device,
+			dev_list);
+
+	return da->devid < db->devid ? -1 :
+		da->devid > db->devid ? 1 : 0;
+}

common/device-utils.h

@@ -58,6 +58,8 @@ int btrfs_prepare_device(int fd, const char *file, u64 *block_count_ret,
 ssize_t btrfs_direct_pread(int fd, void *buf, size_t count, off_t offset);
 ssize_t btrfs_direct_pwrite(int fd, const void *buf, size_t count, off_t offset);
 
+int cmp_device_id(void *priv, struct list_head *a, struct list_head *b);
+
 #ifdef BTRFS_ZONED
 static inline ssize_t btrfs_pwrite(int fd, const void *buf, size_t count,
 				   off_t offset, bool direct)

mkfs/main.c

@@ -512,13 +512,6 @@ static int zero_output_file(int out_fd, u64 size)
 	return ret;
 }
 
-static int _cmp_device_by_id(void *priv, struct list_head *a,
-			     struct list_head *b)
-{
-	return list_entry(a, struct btrfs_device, dev_list)->devid -
-	       list_entry(b, struct btrfs_device, dev_list)->devid;
-}
-
 static void list_all_devices(struct btrfs_root *root, bool is_zoned)
 {
 	struct btrfs_fs_devices *fs_devices;
@@ -532,7 +525,7 @@ static void list_all_devices(struct btrfs_root *root, bool is_zoned)
 	list_for_each_entry(device, &fs_devices->devices, dev_list)
 		number_of_devices++;
 
-	list_sort(NULL, &fs_devices->devices, _cmp_device_by_id);
+	list_sort(NULL, &fs_devices->devices, cmp_device_id);
 
 	printf("Number of devices:  %d\n", number_of_devices);
 	printf("Devices:\n");