fs_dir.c

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#ifndef __KERNEL__
#       define __KERNEL__
#endif


#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/version.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/statfs.h>
#include <linux/mm.h>
#include <asm/uaccess.h>
#include <asm/errno.h>
#include <linux/buffer_head.h>
#include <linux/pagemap.h> /* unlock_page */
#include <linux/proc_fs.h>
#include <asm/atomic.h>
#include <linux/string.h>


#include "fsc_device.h"
#include "rkfs.h"
#include "parser.h"


struct file_operations rkfs_dops = {
        read: generic_read_dir,
        readdir: rkfs_file_readdir,
        fsync: simple_sync_file
};


int rkfs_mkdir(struct inode * dir, struct dentry *dentry, int mode) {
        struct inode * inode;
        struct super_block *sb = dir->i_sb;
        int err = -EMLINK;
        char query_string[MAX_QUERY_LENGTH + 1];

        snprintf(query_string, MAX_QUERY_LENGTH + 1, "MYSQL1.1 MD %lu %s", dir->i_ino, dentry->d_name.name);

        if (query(query_string, strlen(query_string)) != RKFS_DEF_QUERY_OK) {           
                return err;
        } 
        else {
                if (ret_command.command_nr == CMD_ER_NR) {
                        return err;
                }
        }

        inode_inc_link_count(dir);
        
        /* allocate an inode */
        inode = iget(sb, rkfs_atoi(ret_command.param));
        
        err = PTR_ERR(inode);
        if (IS_ERR(inode)) {
                inode_dec_link_count(dir);
                return err;
        }
        /* size of the new directory is 0 - no files inside */
        inode->i_size = 0; 
        
        /* create as dir, with wanted mode */
        inode->i_mode = S_IFDIR | mode; 
        
        /* set the directory ops */
        inode->i_fop = &rkfs_dops;
        
        /* set the inode ops */ 
        inode->i_op = &rkfs_iops;
        
        /* number of hardlinks for the new directory is 2 - one for . and one for .. directory */ 
        inode->i_nlink =2; 

        d_instantiate(dentry, inode);
        
        /* parent directory size increases by one for this new directory */ 
        dir->i_size++;
        return 0; /* ok */
}


int rkfs_rmdir(struct inode * dir, struct dentry *dentry) {
        /* get pointer to a coresponding inode */
        struct inode * inode = dentry->d_inode;
        int err = -ENOTEMPTY;
        char query_string[MAX_QUERY_LENGTH + 1];

        FSPDEBUG("rkfs_rmdir for file '%s'\n", dentry->d_name.name);

        if (inode->i_size == 0) {
                snprintf(query_string, MAX_QUERY_LENGTH + 1, "MYSQL1.1 RD %lu", inode->i_ino);
                if (query(query_string, strlen(query_string)) != RKFS_DEF_QUERY_OK) {
                        return -EFAULT;
                } 
                else {
                        if (ret_command.command_nr == CMD_ER_NR) {
                                return -EFAULT;
                        }
                }
                inode->i_size = 0;
                inode_dec_link_count(inode);
                inode_dec_link_count(dir);
                
                /* parent directory size decreases by one for this removed directory */ 
                dir->i_size--;
                return 0;
        } 
        else {
                /* directory was not empty */
                return err;
        } 
}

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