/* * 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/smp_lock.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)) printk(KERN_WARNING "EFS: WARNING: find_entry(): directory size not a multiple of EFS_DIRBSIZE\n"); for(block = 0; block < inode->i_blocks; block++) { bh = sb_bread(inode->i_sb, efs_bmap(inode, block)); if (!bh) { printk(KERN_ERR "EFS: find_entry(): failed to read dir block %d\n", block); return 0; } dirblock = (struct efs_dir *) bh->b_data; if (be16_to_cpu(dirblock->magic) != EFS_DIRBLK_MAGIC) { printk(KERN_ERR "EFS: find_entry(): invalid directory block\n"); 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, struct nameidata *nd) { efs_ino_t inodenum; struct inode * inode = NULL; lock_kernel(); inodenum = efs_find_entry(dir, dentry->d_name.name, dentry->d_name.len); if (inodenum) { inode = efs_iget(dir->i_sb, inodenum); if (IS_ERR(inode)) { unlock_kernel(); return ERR_CAST(inode); } } unlock_kernel(); d_add(dentry, inode); return NULL; } 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; struct inode *inode; efs_ino_t ino; long error; lock_kernel(); error = -ENOENT; ino = efs_find_entry(child->d_inode, "..", 2); if (!ino) goto fail; inode = efs_iget(child->d_inode->i_sb, ino); if (IS_ERR(inode)) { error = PTR_ERR(inode); goto fail; } error = -ENOMEM; parent = d_alloc_anon(inode); if (!parent) goto fail_iput; unlock_kernel(); return parent; fail_iput: iput(inode); fail: unlock_kernel(); return ERR_PTR(error); }