Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / fs / efs / namei.c

diff --git a/kernel/fs/efs/namei.c b/kernel/fs/efs/namei.c
new file mode 100644 (file)
index 0000000..40ba9cc
--- /dev/null
+++ b/kernel/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;
+}