Aadjust print function and fix compiler warning

Align the print function with the Simplefs print format for consistency.
Also adjust variable declarations to fix compiler warnings when building
under the C90 standard.

Author: RoyWFHuang

bitmap.h

@@ -48,11 +48,11 @@ static inline uint32_t get_free_blocks(struct super_block *sb, uint32_t len)
     struct simplefs_sb_info *sbi = SIMPLEFS_SB(sb);
     uint32_t ret = get_first_free_bits(sbi->bfree_bitmap, sbi->nr_blocks, len);
     uint32_t i;
+    struct buffer_head *bh;
     if (!ret) /* No enough free blocks */
         return 0;
 
     sbi->nr_free_blocks -= len;
-    struct buffer_head *bh;
     for (i = 0; i < len; i++) {
         bh = sb_bread(sb, ret + i);
         if (!bh) {

inode.c

@@ -996,7 +996,7 @@ static int simplefs_link(struct dentry *old_dentry,
     eblock = (struct simplefs_file_ei_block *) bh->b_data;
     if (eblock->nr_files == SIMPLEFS_MAX_SUBFILES) {
         ret = -EMLINK;
-        printk(KERN_INFO "directory is full");
+        pr_info("directory is full");
         goto end;
     }
 
@@ -1097,7 +1097,7 @@ static int simplefs_symlink(struct inode *dir,
 
     if (eblock->nr_files == SIMPLEFS_MAX_SUBFILES) {
         ret = -EMLINK;
-        printk(KERN_INFO "directory is full");
+        pr_info("directory is full");
         goto end;
     }
 

super.c

@@ -293,23 +293,21 @@ static journal_t *simplefs_get_dev_journal(struct super_block *sb,
 
 #if SIMPLEFS_AT_LEAST(6, 9, 0)
     if (IS_ERR(bdev_file)) {
-        printk(KERN_ERR
-               "failed to open journal device unknown-block(%u,%u) %ld\n",
+        pr_err("failed to open journal device unknown-block(%u,%u) %ld\n",
                MAJOR(journal_dev), MINOR(journal_dev), PTR_ERR(bdev_file));
         return ERR_CAST(bdev_file);
     }
     bdev = file_bdev(bdev_file);
 #elif SIMPLEFS_AT_LEAST(6, 7, 0)
     if (IS_ERR(bdev_handle)) {
-        printk(KERN_ERR
-               "failed to open journal device unknown-block(%u,%u) %ld\n",
+        pr_err("failed to open journal device unknown-block(%u,%u) %ld\n",
                MAJOR(journal_dev), MINOR(journal_dev), PTR_ERR(bdev_handle));
         return ERR_CAST(bdev_handle);
     }
     bdev = bdev_handle->bdev;
 #elif SIMPLEFS_AT_LEAST(5, 10, 0)
     if (IS_ERR(bdev)) {
-        printk(KERN_ERR "failed to open block device (%u:%u), error: %ld\n",
+        pr_err("failed to open block device (%u:%u), error: %ld\n",
                MAJOR(journal_dev), MINOR(journal_dev), PTR_ERR(bdev));
         return ERR_CAST(bdev);
     }