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root/fs/hfsplus/dir.c

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DEFINITIONS

This source file includes following definitions.
  1. hfsplus_instantiate
  2. hfsplus_lookup
  3. hfsplus_readdir
  4. hfsplus_dir_release
  5. hfsplus_create
  6. hfsplus_link
  7. hfsplus_unlink
  8. hfsplus_mkdir
  9. hfsplus_rmdir
  10. hfsplus_symlink
  11. hfsplus_mknod
  12. hfsplus_rename

/*
 *  linux/fs/hfsplus/dir.c
 *
 * Copyright (C) 2001
 * Brad Boyer (flar@allandria.com)
 * (C) 2003 Ardis Technologies <roman@ardistech.com>
 *
 * Handling of directories
 */

#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/random.h>

#include "hfsplus_fs.h"
#include "hfsplus_raw.h"

static inline void hfsplus_instantiate(struct dentry *dentry,
                                       struct inode *inode, u32 cnid)
{
        dentry->d_fsdata = (void *)(unsigned long)cnid;
        d_instantiate(dentry, inode);
}

/* Find the entry inside dir named dentry->d_name */
static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
                                     struct nameidata *nd)
{
        struct inode *inode = NULL;
        struct hfs_find_data fd;
        struct super_block *sb;
        hfsplus_cat_entry entry;
        int err;
        u32 cnid, linkid = 0;
        u16 type;

        sb = dir->i_sb;

        dentry->d_op = &hfsplus_dentry_operations;
        dentry->d_fsdata = NULL;
        hfs_find_init(HFSPLUS_SB(sb).cat_tree, &fd);
        hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);
again:
        err = hfs_brec_read(&fd, &entry, sizeof(entry));
        if (err) {
                if (err == -ENOENT) {
                        hfs_find_exit(&fd);
                        /* No such entry */
                        inode = NULL;
                        goto out;
                }
                goto fail;
        }
        type = be16_to_cpu(entry.type);
        if (type == HFSPLUS_FOLDER) {
                if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
                        err = -EIO;
                        goto fail;
                }
                cnid = be32_to_cpu(entry.folder.id);
                dentry->d_fsdata = (void *)(unsigned long)cnid;
        } else if (type == HFSPLUS_FILE) {
                if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
                        err = -EIO;
                        goto fail;
                }
                cnid = be32_to_cpu(entry.file.id);
                if (entry.file.user_info.fdType == cpu_to_be32(HFSP_HARDLINK_TYPE) &&
                    entry.file.user_info.fdCreator == cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
                    (entry.file.create_date == HFSPLUS_I(HFSPLUS_SB(sb).hidden_dir).create_date ||
                     entry.file.create_date == HFSPLUS_I(sb->s_root->d_inode).create_date) &&
                    HFSPLUS_SB(sb).hidden_dir) {
                        struct qstr str;
                        char name[32];

                        if (dentry->d_fsdata) {
                                /*
                                 * We found a link pointing to another link,
                                 * so ignore it and treat it as regular file.
                                 */
                                cnid = (unsigned long)dentry->d_fsdata;
                                linkid = 0;
                        } else {
                                dentry->d_fsdata = (void *)(unsigned long)cnid;
                                linkid = be32_to_cpu(entry.file.permissions.dev);
                                str.len = sprintf(name, "iNode%d", linkid);
                                str.name = name;
                                hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_SB(sb).hidden_dir->i_ino, &str);
                                goto again;
                        }
                } else if (!dentry->d_fsdata)
                        dentry->d_fsdata = (void *)(unsigned long)cnid;
        } else {
                printk(KERN_ERR "hfs: invalid catalog entry type in lookup\n");
                err = -EIO;
                goto fail;
        }
        hfs_find_exit(&fd);
        inode = hfsplus_iget(dir->i_sb, cnid);
        if (IS_ERR(inode))
                return ERR_CAST(inode);
        if (S_ISREG(inode->i_mode))
                HFSPLUS_I(inode).dev = linkid;
out:
        d_add(dentry, inode);
        return NULL;
fail:
        hfs_find_exit(&fd);
        return ERR_PTR(err);
}

static int hfsplus_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
        struct inode *inode = filp->f_path.dentry->d_inode;
        struct super_block *sb = inode->i_sb;
        int len, err;
        char strbuf[HFSPLUS_MAX_STRLEN + 1];
        hfsplus_cat_entry entry;
        struct hfs_find_data fd;
        struct hfsplus_readdir_data *rd;
        u16 type;

        if (filp->f_pos >= inode->i_size)
                return 0;

        hfs_find_init(HFSPLUS_SB(sb).cat_tree, &fd);
        hfsplus_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
        err = hfs_brec_find(&fd);
        if (err)
                goto out;

        switch ((u32)filp->f_pos) {
        case 0:
                /* This is completely artificial... */
                if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR))
                        goto out;
                filp->f_pos++;
                /* fall through */
        case 1:
                hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
                if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
                        printk(KERN_ERR "hfs: bad catalog folder thread\n");
                        err = -EIO;
                        goto out;
                }
                if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
                        printk(KERN_ERR "hfs: truncated catalog thread\n");
                        err = -EIO;
                        goto out;
                }
                if (filldir(dirent, "..", 2, 1,
                            be32_to_cpu(entry.thread.parentID), DT_DIR))
                        goto out;
                filp->f_pos++;
                /* fall through */
        default:
                if (filp->f_pos >= inode->i_size)
                        goto out;
                err = hfs_brec_goto(&fd, filp->f_pos - 1);
                if (err)
                        goto out;
        }

        for (;;) {
                if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
                        printk(KERN_ERR "hfs: walked past end of dir\n");
                        err = -EIO;
                        goto out;
                }
                hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
                type = be16_to_cpu(entry.type);
                len = HFSPLUS_MAX_STRLEN;
                err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
                if (err)
                        goto out;
                if (type == HFSPLUS_FOLDER) {
                        if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
                                printk(KERN_ERR "hfs: small dir entry\n");
                                err = -EIO;
                                goto out;
                        }
                        if (HFSPLUS_SB(sb).hidden_dir &&
                            HFSPLUS_SB(sb).hidden_dir->i_ino == be32_to_cpu(entry.folder.id))
                                goto next;
                        if (filldir(dirent, strbuf, len, filp->f_pos,
                                    be32_to_cpu(entry.folder.id), DT_DIR))
                                break;
                } else if (type == HFSPLUS_FILE) {
                        if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
                                printk(KERN_ERR "hfs: small file entry\n");
                                err = -EIO;
                                goto out;
                        }
                        if (filldir(dirent, strbuf, len, filp->f_pos,
                                    be32_to_cpu(entry.file.id), DT_REG))
                                break;
                } else {
                        printk(KERN_ERR "hfs: bad catalog entry type\n");
                        err = -EIO;
                        goto out;
                }
        next:
                filp->f_pos++;
                if (filp->f_pos >= inode->i_size)
                        goto out;
                err = hfs_brec_goto(&fd, 1);
                if (err)
                        goto out;
        }
        rd = filp->private_data;
        if (!rd) {
                rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
                if (!rd) {
                        err = -ENOMEM;
                        goto out;
                }
                filp->private_data = rd;
                rd->file = filp;
                list_add(&rd->list, &HFSPLUS_I(inode).open_dir_list);
        }
        memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
out:
        hfs_find_exit(&fd);
        return err;
}

static int hfsplus_dir_release(struct inode *inode, struct file *file)
{
        struct hfsplus_readdir_data *rd = file->private_data;
        if (rd) {
                list_del(&rd->list);
                kfree(rd);
        }
        return 0;
}

static int hfsplus_create(struct inode *dir, struct dentry *dentry, int mode,
                          struct nameidata *nd)
{
        struct inode *inode;
        int res;

        inode = hfsplus_new_inode(dir->i_sb, mode);
        if (!inode)
                return -ENOSPC;

        res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
        if (res) {
                inode->i_nlink = 0;
                hfsplus_delete_inode(inode);
                iput(inode);
                return res;
        }
        hfsplus_instantiate(dentry, inode, inode->i_ino);
        mark_inode_dirty(inode);
        return 0;
}

static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
                        struct dentry *dst_dentry)
{
        struct super_block *sb = dst_dir->i_sb;
        struct inode *inode = src_dentry->d_inode;
        struct inode *src_dir = src_dentry->d_parent->d_inode;
        struct qstr str;
        char name[32];
        u32 cnid, id;
        int res;

        if (HFSPLUS_IS_RSRC(inode))
                return -EPERM;

        if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
                for (;;) {
                        get_random_bytes(&id, sizeof(cnid));
                        id &= 0x3fffffff;
                        str.name = name;
                        str.len = sprintf(name, "iNode%d", id);
                        res = hfsplus_rename_cat(inode->i_ino,
                                                 src_dir, &src_dentry->d_name,
                                                 HFSPLUS_SB(sb).hidden_dir, &str);
                        if (!res)
                                break;
                        if (res != -EEXIST)
                                return res;
                }
                HFSPLUS_I(inode).dev = id;
                cnid = HFSPLUS_SB(sb).next_cnid++;
                src_dentry->d_fsdata = (void *)(unsigned long)cnid;
                res = hfsplus_create_cat(cnid, src_dir, &src_dentry->d_name, inode);
                if (res)
                        /* panic? */
                        return res;
                HFSPLUS_SB(sb).file_count++;
        }
        cnid = HFSPLUS_SB(sb).next_cnid++;
        res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
        if (res)
                return res;

        inc_nlink(inode);
        hfsplus_instantiate(dst_dentry, inode, cnid);
        atomic_inc(&inode->i_count);
        inode->i_ctime = CURRENT_TIME_SEC;
        mark_inode_dirty(inode);
        HFSPLUS_SB(sb).file_count++;
        sb->s_dirt = 1;

        return 0;
}

static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
{
        struct super_block *sb = dir->i_sb;
        struct inode *inode = dentry->d_inode;
        struct qstr str;
        char name[32];
        u32 cnid;
        int res;

        if (HFSPLUS_IS_RSRC(inode))
                return -EPERM;

        cnid = (u32)(unsigned long)dentry->d_fsdata;
        if (inode->i_ino == cnid &&
            atomic_read(&HFSPLUS_I(inode).opencnt)) {
                str.name = name;
                str.len = sprintf(name, "temp%lu", inode->i_ino);
                res = hfsplus_rename_cat(inode->i_ino,
                                         dir, &dentry->d_name,
                                         HFSPLUS_SB(sb).hidden_dir, &str);
                if (!res)
                        inode->i_flags |= S_DEAD;
                return res;
        }
        res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
        if (res)
                return res;

        if (inode->i_nlink > 0)
                drop_nlink(inode);
        if (inode->i_ino == cnid)
                clear_nlink(inode);
        if (!inode->i_nlink) {
                if (inode->i_ino != cnid) {
                        HFSPLUS_SB(sb).file_count--;
                        if (!atomic_read(&HFSPLUS_I(inode).opencnt)) {
                                res = hfsplus_delete_cat(inode->i_ino,
                                                         HFSPLUS_SB(sb).hidden_dir,
                                                         NULL);
                                if (!res)
                                        hfsplus_delete_inode(inode);
                        } else
                                inode->i_flags |= S_DEAD;
                } else
                        hfsplus_delete_inode(inode);
        } else
                HFSPLUS_SB(sb).file_count--;
        inode->i_ctime = CURRENT_TIME_SEC;
        mark_inode_dirty(inode);

        return res;
}

static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
        struct inode *inode;
        int res;

        inode = hfsplus_new_inode(dir->i_sb, S_IFDIR | mode);
        if (!inode)
                return -ENOSPC;

        res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
        if (res) {
                inode->i_nlink = 0;
                hfsplus_delete_inode(inode);
                iput(inode);
                return res;
        }
        hfsplus_instantiate(dentry, inode, inode->i_ino);
        mark_inode_dirty(inode);
        return 0;
}

static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
{
        struct inode *inode;
        int res;

        inode = dentry->d_inode;
        if (inode->i_size != 2)
                return -ENOTEMPTY;
        res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
        if (res)
                return res;
        clear_nlink(inode);
        inode->i_ctime = CURRENT_TIME_SEC;
        hfsplus_delete_inode(inode);
        mark_inode_dirty(inode);
        return 0;
}

static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
                           const char *symname)
{
        struct super_block *sb;
        struct inode *inode;
        int res;

        sb = dir->i_sb;
        inode = hfsplus_new_inode(sb, S_IFLNK | S_IRWXUGO);
        if (!inode)
                return -ENOSPC;

        res = page_symlink(inode, symname, strlen(symname) + 1);
        if (res) {
                inode->i_nlink = 0;
                hfsplus_delete_inode(inode);
                iput(inode);
                return res;
        }

        mark_inode_dirty(inode);
        res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);

        if (!res) {
                hfsplus_instantiate(dentry, inode, inode->i_ino);
                mark_inode_dirty(inode);
        }

        return res;
}

static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
                         int mode, dev_t rdev)
{
        struct super_block *sb;
        struct inode *inode;
        int res;

        sb = dir->i_sb;
        inode = hfsplus_new_inode(sb, mode);
        if (!inode)
                return -ENOSPC;

        res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
        if (res) {
                inode->i_nlink = 0;
                hfsplus_delete_inode(inode);
                iput(inode);
                return res;
        }
        init_special_inode(inode, mode, rdev);
        hfsplus_instantiate(dentry, inode, inode->i_ino);
        mark_inode_dirty(inode);

        return 0;
}

static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
                          struct inode *new_dir, struct dentry *new_dentry)
{
        int res;

        /* Unlink destination if it already exists */
        if (new_dentry->d_inode) {
                res = hfsplus_unlink(new_dir, new_dentry);
                if (res)
                        return res;
        }

        res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
                                 old_dir, &old_dentry->d_name,
                                 new_dir, &new_dentry->d_name);
        if (!res)
                new_dentry->d_fsdata = old_dentry->d_fsdata;
        return res;
}

const struct inode_operations hfsplus_dir_inode_operations = {
        .lookup         = hfsplus_lookup,
        .create         = hfsplus_create,
        .link           = hfsplus_link,
        .unlink         = hfsplus_unlink,
        .mkdir          = hfsplus_mkdir,
        .rmdir          = hfsplus_rmdir,
        .symlink        = hfsplus_symlink,
        .mknod          = hfsplus_mknod,
        .rename         = hfsplus_rename,
};

const struct file_operations hfsplus_dir_operations = {
        .read           = generic_read_dir,
        .readdir        = hfsplus_readdir,
        .ioctl          = hfsplus_ioctl,
        .llseek         = generic_file_llseek,
        .release        = hfsplus_dir_release,
};

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