summaryrefslogtreecommitdiff
path: root/include/linux/exportfs.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux/exportfs.h')
-rw-r--r--include/linux/exportfs.h56
1 files changed, 50 insertions, 6 deletions
diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h
index bb37ad5cc954..25c4a5afbd44 100644
--- a/include/linux/exportfs.h
+++ b/include/linux/exportfs.h
@@ -3,6 +3,7 @@
#define LINUX_EXPORTFS_H 1
#include <linux/types.h>
+#include <linux/path.h>
struct dentry;
struct iattr;
@@ -156,8 +157,33 @@ struct fid {
};
};
+enum handle_to_path_flags {
+ HANDLE_CHECK_PERMS = (1 << 0),
+ HANDLE_CHECK_SUBTREE = (1 << 1),
+};
+
+struct handle_to_path_ctx {
+ struct path root;
+ enum handle_to_path_flags flags;
+ unsigned int fh_flags;
+};
+
#define EXPORT_FH_CONNECTABLE 0x1 /* Encode file handle with parent */
#define EXPORT_FH_FID 0x2 /* File handle may be non-decodeable */
+#define EXPORT_FH_DIR_ONLY 0x4 /* Only decode file handle for a directory */
+
+/*
+ * Filesystems use only lower 8 bits of file_handle type for fid_type.
+ * name_to_handle_at() uses upper 16 bits of type as user flags to be
+ * interpreted by open_by_handle_at().
+ */
+#define FILEID_USER_FLAGS_MASK 0xffff0000
+#define FILEID_USER_FLAGS(type) ((type) & FILEID_USER_FLAGS_MASK)
+
+/* Flags supported in encoded handle_type that is exported to user */
+#define FILEID_IS_CONNECTABLE 0x10000
+#define FILEID_IS_DIR 0x20000
+#define FILEID_VALID_USER_FLAGS (FILEID_IS_CONNECTABLE | FILEID_IS_DIR)
/**
* struct export_operations - for nfsd to communicate with file systems
@@ -211,6 +237,12 @@ struct fid {
* is also a directory. In the event that it cannot be found, or storage
* space cannot be allocated, a %ERR_PTR should be returned.
*
+ * permission:
+ * Allow filesystems to specify a custom permission function.
+ *
+ * open:
+ * Allow filesystems to specify a custom open function.
+ *
* commit_metadata:
* @commit_metadata should commit metadata changes to stable storage.
*
@@ -237,6 +269,8 @@ struct export_operations {
bool write, u32 *device_generation);
int (*commit_blocks)(struct inode *inode, struct iomap *iomaps,
int nr_iomaps, struct iattr *iattr);
+ int (*permission)(struct handle_to_path_ctx *ctx, unsigned int oflags);
+ struct file * (*open)(struct path *path, unsigned int oflags);
#define EXPORT_OP_NOWCC (0x1) /* don't collect v3 wcc data */
#define EXPORT_OP_NOSUBTREECHK (0x2) /* no subtree checking */
#define EXPORT_OP_CLOSE_BEFORE_UNLINK (0x4) /* close files before unlink */
@@ -245,21 +279,20 @@ struct export_operations {
atomic attribute updates
*/
#define EXPORT_OP_FLUSH_ON_CLOSE (0x20) /* fs flushes file data on close */
-#define EXPORT_OP_ASYNC_LOCK (0x40) /* fs can do async lock request */
+#define EXPORT_OP_NOLOCKS (0x40) /* no file locking support */
unsigned long flags;
};
/**
- * exportfs_lock_op_is_async() - export op supports async lock operation
+ * exportfs_cannot_lock() - check if export implements file locking
* @export_ops: the nfs export operations to check
*
- * Returns true if the nfs export_operations structure has
- * EXPORT_OP_ASYNC_LOCK in their flags set
+ * Returns true if the export does not support file locking.
*/
static inline bool
-exportfs_lock_op_is_async(const struct export_operations *export_ops)
+exportfs_cannot_lock(const struct export_operations *export_ops)
{
- return export_ops->flags & EXPORT_OP_ASYNC_LOCK;
+ return export_ops->flags & EXPORT_OP_NOLOCKS;
}
extern int exportfs_encode_inode_fh(struct inode *inode, struct fid *fid,
@@ -281,6 +314,9 @@ static inline bool exportfs_can_decode_fh(const struct export_operations *nop)
static inline bool exportfs_can_encode_fh(const struct export_operations *nop,
int fh_flags)
{
+ if (!nop)
+ return false;
+
/*
* If a non-decodeable file handle was requested, we only need to make
* sure that filesystem did not opt-out of encoding fid.
@@ -289,6 +325,13 @@ static inline bool exportfs_can_encode_fh(const struct export_operations *nop,
return exportfs_can_encode_fid(nop);
/*
+ * If a connectable file handle was requested, we need to make sure that
+ * filesystem can also decode connected file handles.
+ */
+ if ((fh_flags & EXPORT_FH_CONNECTABLE) && !nop->fh_to_parent)
+ return false;
+
+ /*
* If a decodeable file handle was requested, we need to make sure that
* filesystem can also decode file handles.
*/
@@ -305,6 +348,7 @@ static inline int exportfs_encode_fid(struct inode *inode, struct fid *fid,
extern struct dentry *exportfs_decode_fh_raw(struct vfsmount *mnt,
struct fid *fid, int fh_len,
int fileid_type,
+ unsigned int flags,
int (*acceptable)(void *, struct dentry *),
void *context);
extern struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid,