diff options
Diffstat (limited to 'fs/efs/namei.c')
-rw-r--r-- | fs/efs/namei.c | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/fs/efs/namei.c b/fs/efs/namei.c new file mode 100644 index 000000000..40ba9cc41 --- /dev/null +++ b/fs/efs/namei.c @@ -0,0 +1,119 @@ +/* + * 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(d_inode(child)->i_sb, ino)); + + return parent; +} |