udf: Make udf exportable
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Rasmus Rohde <rohde@duff.dk>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/udf/namei.c b/fs/udf/namei.c
index ba5537d..47a6589 100644
--- a/fs/udf/namei.c
+++ b/fs/udf/namei.c
@@ -32,6 +32,7 @@
#include <linux/buffer_head.h>
#include <linux/sched.h>
#include <linux/crc-itu-t.h>
+#include <linux/exportfs.h>
static inline int udf_match(int len1, const char *name1, int len2,
const char *name2)
@@ -158,6 +159,8 @@
sector_t offset;
struct extent_position epos = {};
struct udf_inode_info *dinfo = UDF_I(dir);
+ int isdotdot = dentry->d_name.len == 2 &&
+ dentry->d_name.name[0] == '.' && dentry->d_name.name[1] == '.';
size = udf_ext0_offset(dir) + dir->i_size;
f_pos = udf_ext0_offset(dir);
@@ -225,6 +228,12 @@
continue;
}
+ if ((cfi->fileCharacteristics & FID_FILE_CHAR_PARENT) &&
+ isdotdot) {
+ brelse(epos.bh);
+ return fi;
+ }
+
if (!lfi)
continue;
@@ -286,9 +295,8 @@
}
}
unlock_kernel();
- d_add(dentry, inode);
- return NULL;
+ return d_splice_alias(inode, dentry);
}
static struct fileIdentDesc *udf_add_entry(struct inode *dir,
@@ -1232,6 +1240,134 @@
return retval;
}
+static struct dentry *udf_get_parent(struct dentry *child)
+{
+ struct dentry *parent;
+ struct inode *inode = NULL;
+ struct dentry dotdot;
+ struct fileIdentDesc cfi;
+ struct udf_fileident_bh fibh;
+
+ dotdot.d_name.name = "..";
+ dotdot.d_name.len = 2;
+
+ lock_kernel();
+ if (!udf_find_entry(child->d_inode, &dotdot, &fibh, &cfi))
+ goto out_unlock;
+
+ if (fibh.sbh != fibh.ebh)
+ brelse(fibh.ebh);
+ brelse(fibh.sbh);
+
+ inode = udf_iget(child->d_inode->i_sb,
+ lelb_to_cpu(cfi.icb.extLocation));
+ if (!inode)
+ goto out_unlock;
+ unlock_kernel();
+
+ parent = d_alloc_anon(inode);
+ if (!parent) {
+ iput(inode);
+ parent = ERR_PTR(-ENOMEM);
+ }
+
+ return parent;
+out_unlock:
+ unlock_kernel();
+ return ERR_PTR(-EACCES);
+}
+
+
+static struct dentry *udf_nfs_get_inode(struct super_block *sb, u32 block,
+ u16 partref, __u32 generation)
+{
+ struct inode *inode;
+ struct dentry *result;
+ kernel_lb_addr loc;
+
+ if (block == 0)
+ return ERR_PTR(-ESTALE);
+
+ loc.logicalBlockNum = block;
+ loc.partitionReferenceNum = partref;
+ inode = udf_iget(sb, loc);
+
+ if (inode == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ if (generation && inode->i_generation != generation) {
+ iput(inode);
+ return ERR_PTR(-ESTALE);
+ }
+ result = d_alloc_anon(inode);
+ if (!result) {
+ iput(inode);
+ return ERR_PTR(-ENOMEM);
+ }
+ return result;
+}
+
+static struct dentry *udf_fh_to_dentry(struct super_block *sb,
+ struct fid *fid, int fh_len, int fh_type)
+{
+ if ((fh_len != 3 && fh_len != 5) ||
+ (fh_type != FILEID_UDF_WITH_PARENT &&
+ fh_type != FILEID_UDF_WITHOUT_PARENT))
+ return NULL;
+
+ return udf_nfs_get_inode(sb, fid->udf.block, fid->udf.partref,
+ fid->udf.generation);
+}
+
+static struct dentry *udf_fh_to_parent(struct super_block *sb,
+ struct fid *fid, int fh_len, int fh_type)
+{
+ if (fh_len != 5 || fh_type != FILEID_UDF_WITH_PARENT)
+ return NULL;
+
+ return udf_nfs_get_inode(sb, fid->udf.parent_block,
+ fid->udf.parent_partref,
+ fid->udf.parent_generation);
+}
+static int udf_encode_fh(struct dentry *de, __u32 *fh, int *lenp,
+ int connectable)
+{
+ int len = *lenp;
+ struct inode *inode = de->d_inode;
+ kernel_lb_addr location = UDF_I(inode)->i_location;
+ struct fid *fid = (struct fid *)fh;
+ int type = FILEID_UDF_WITHOUT_PARENT;
+
+ if (len < 3 || (connectable && len < 5))
+ return 255;
+
+ *lenp = 3;
+ fid->udf.block = location.logicalBlockNum;
+ fid->udf.partref = location.partitionReferenceNum;
+ fid->udf.generation = inode->i_generation;
+
+ if (connectable && !S_ISDIR(inode->i_mode)) {
+ spin_lock(&de->d_lock);
+ inode = de->d_parent->d_inode;
+ location = UDF_I(inode)->i_location;
+ fid->udf.parent_block = location.logicalBlockNum;
+ fid->udf.parent_partref = location.partitionReferenceNum;
+ fid->udf.parent_generation = inode->i_generation;
+ spin_unlock(&de->d_lock);
+ *lenp = 5;
+ type = FILEID_UDF_WITH_PARENT;
+ }
+
+ return type;
+}
+
+const struct export_operations udf_export_ops = {
+ .encode_fh = udf_encode_fh,
+ .fh_to_dentry = udf_fh_to_dentry,
+ .fh_to_parent = udf_fh_to_parent,
+ .get_parent = udf_get_parent,
+};
+
const struct inode_operations udf_dir_inode_operations = {
.lookup = udf_lookup,
.create = udf_create,
diff --git a/fs/udf/super.c b/fs/udf/super.c
index b564fc1..260f4b82 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1933,6 +1933,7 @@
/* Fill in the rest of the superblock */
sb->s_op = &udf_sb_ops;
+ sb->s_export_op = &udf_export_ops;
sb->dq_op = NULL;
sb->s_dirt = 0;
sb->s_magic = UDF_SUPER_MAGIC;
diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h
index f3f45d0..8fa9c2d 100644
--- a/fs/udf/udfdecl.h
+++ b/fs/udf/udfdecl.h
@@ -73,6 +73,7 @@
struct buffer_head;
struct super_block;
+extern const struct export_operations udf_export_ops;
extern const struct inode_operations udf_dir_inode_operations;
extern const struct file_operations udf_dir_operations;
extern const struct inode_operations udf_file_inode_operations;