mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-16 16:36:58 +07:00
fc64005c93
... and neither can ever be NULL Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
120 lines
2.6 KiB
C
120 lines
2.6 KiB
C
/*
|
|
* namei.c
|
|
*
|
|
* Copyright (c) 1999 Al Smith
|
|
*
|
|
* Portions derived from work (c) 1995,1996 Christian Vogelgsang.
|
|
*/
|
|
|
|
#include <linux/buffer_head.h>
|
|
#include <linux/string.h>
|
|
#include <linux/exportfs.h>
|
|
#include "efs.h"
|
|
|
|
|
|
static efs_ino_t efs_find_entry(struct inode *inode, const char *name, int len)
|
|
{
|
|
struct buffer_head *bh;
|
|
|
|
int slot, namelen;
|
|
char *nameptr;
|
|
struct efs_dir *dirblock;
|
|
struct efs_dentry *dirslot;
|
|
efs_ino_t inodenum;
|
|
efs_block_t block;
|
|
|
|
if (inode->i_size & (EFS_DIRBSIZE-1))
|
|
pr_warn("%s(): directory size not a multiple of EFS_DIRBSIZE\n",
|
|
__func__);
|
|
|
|
for(block = 0; block < inode->i_blocks; block++) {
|
|
|
|
bh = sb_bread(inode->i_sb, efs_bmap(inode, block));
|
|
if (!bh) {
|
|
pr_err("%s(): failed to read dir block %d\n",
|
|
__func__, block);
|
|
return 0;
|
|
}
|
|
|
|
dirblock = (struct efs_dir *) bh->b_data;
|
|
|
|
if (be16_to_cpu(dirblock->magic) != EFS_DIRBLK_MAGIC) {
|
|
pr_err("%s(): invalid directory block\n", __func__);
|
|
brelse(bh);
|
|
return 0;
|
|
}
|
|
|
|
for (slot = 0; slot < dirblock->slots; slot++) {
|
|
dirslot = (struct efs_dentry *) (((char *) bh->b_data) + EFS_SLOTAT(dirblock, slot));
|
|
|
|
namelen = dirslot->namelen;
|
|
nameptr = dirslot->name;
|
|
|
|
if ((namelen == len) && (!memcmp(name, nameptr, len))) {
|
|
inodenum = be32_to_cpu(dirslot->inode);
|
|
brelse(bh);
|
|
return inodenum;
|
|
}
|
|
}
|
|
brelse(bh);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
struct dentry *efs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
|
|
{
|
|
efs_ino_t inodenum;
|
|
struct inode *inode = NULL;
|
|
|
|
inodenum = efs_find_entry(dir, dentry->d_name.name, dentry->d_name.len);
|
|
if (inodenum)
|
|
inode = efs_iget(dir->i_sb, inodenum);
|
|
|
|
return d_splice_alias(inode, dentry);
|
|
}
|
|
|
|
static struct inode *efs_nfs_get_inode(struct super_block *sb, u64 ino,
|
|
u32 generation)
|
|
{
|
|
struct inode *inode;
|
|
|
|
if (ino == 0)
|
|
return ERR_PTR(-ESTALE);
|
|
inode = efs_iget(sb, ino);
|
|
if (IS_ERR(inode))
|
|
return ERR_CAST(inode);
|
|
|
|
if (generation && inode->i_generation != generation) {
|
|
iput(inode);
|
|
return ERR_PTR(-ESTALE);
|
|
}
|
|
|
|
return inode;
|
|
}
|
|
|
|
struct dentry *efs_fh_to_dentry(struct super_block *sb, struct fid *fid,
|
|
int fh_len, int fh_type)
|
|
{
|
|
return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
|
|
efs_nfs_get_inode);
|
|
}
|
|
|
|
struct dentry *efs_fh_to_parent(struct super_block *sb, struct fid *fid,
|
|
int fh_len, int fh_type)
|
|
{
|
|
return generic_fh_to_parent(sb, fid, fh_len, fh_type,
|
|
efs_nfs_get_inode);
|
|
}
|
|
|
|
struct dentry *efs_get_parent(struct dentry *child)
|
|
{
|
|
struct dentry *parent = ERR_PTR(-ENOENT);
|
|
efs_ino_t ino;
|
|
|
|
ino = efs_find_entry(d_inode(child), "..", 2);
|
|
if (ino)
|
|
parent = d_obtain_alias(efs_iget(child->d_sb, ino));
|
|
|
|
return parent;
|
|
}
|