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/*
* linux/fs/hfs/sysdep.c
*
* Copyright (C) 1996 Paul H. Hargrove
* This file may be distributed under the terms of the GNU General Public License.
*
* This file contains the code to do various system dependent things.
*
* "XXX" in a comment is a note to myself to consider changing something.
*
* In function preconditions the term "valid" applied to a pointer to
* a structure means that the pointer is non-NULL and the structure it
* points to has all fields initialized to consistent values.
*/
#include "hfs.h"
#include <linux/hfs_fs_sb.h>
#include <linux/hfs_fs_i.h>
#include <linux/hfs_fs.h>
#include <linux/smp_lock.h>
static int hfs_revalidate_dentry(struct dentry *, int);
static int hfs_hash_dentry(struct dentry *, struct qstr *);
static int hfs_compare_dentry(struct dentry *, struct qstr *, struct qstr *);
static void hfs_dentry_iput(struct dentry *, struct inode *);
struct dentry_operations hfs_dentry_operations =
{
d_revalidate: hfs_revalidate_dentry,
d_hash: hfs_hash_dentry,
d_compare: hfs_compare_dentry,
d_iput: hfs_dentry_iput,
};
/*
* hfs_buffer_get()
*
* Return a buffer for the 'block'th block of the media.
* If ('read'==0) then the buffer is not read from disk.
*/
hfs_buffer hfs_buffer_get(hfs_sysmdb sys_mdb, int block, int read) {
hfs_buffer tmp = HFS_BAD_BUFFER;
if (read) {
tmp = sb_bread(sys_mdb, block);
} else {
tmp = sb_getblk(sys_mdb, block);
if (tmp) {
mark_buffer_uptodate(tmp, 1);
}
}
if (!tmp) {
hfs_error("hfs_fs: unable to read block 0x%08x from dev %s\n",
block, hfs_mdb_name(sys_mdb));
}
return tmp;
}
/* dentry case-handling: just lowercase everything */
/* hfs_strhash now uses the same hashing function as the dcache. */
static int hfs_hash_dentry(struct dentry *dentry, struct qstr *this)
{
if (this->len > HFS_NAMELEN)
return 0;
this->hash = hfs_strhash(this->name, this->len);
return 0;
}
/* return 1 on failure and 0 on success */
static int hfs_compare_dentry(struct dentry *dentry, struct qstr *a,
struct qstr *b)
{
if (a->len != b->len) return 1;
if (a->len > HFS_NAMELEN)
return 1;
return !hfs_streq(a->name, a->len, b->name, b->len);
}
static void hfs_dentry_iput(struct dentry *dentry, struct inode *inode)
{
struct hfs_cat_entry *entry = HFS_I(inode)->entry;
lock_kernel();
entry->sys_entry[HFS_ITYPE_TO_INT(HFS_ITYPE(inode->i_ino))] = NULL;
unlock_kernel();
iput(inode);
}
static int hfs_revalidate_dentry(struct dentry *dentry, int flags)
{
struct inode *inode = dentry->d_inode;
int diff;
/* fix up inode on a timezone change */
lock_kernel();
if (inode &&
(diff = (hfs_to_utc(0) - HFS_I(inode)->tz_secondswest))) {
inode->i_ctime += diff;
inode->i_atime += diff;
inode->i_mtime += diff;
HFS_I(inode)->tz_secondswest += diff;
}
unlock_kernel();
return 1;
}
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