1 /* 2 * 3 * Definitions for mount interface. This describes the in the kernel build 4 * linkedlist with mounted filesystems. 5 * 6 * Author: Marco van Wieringen <[email protected]> 7 * 8 * Version: $Id: mount.h,v 2.0 1996/11/17 16:48:14 mvw Exp mvw $ 9 * 10 */ 11 #ifndef _LINUX_MOUNT_H 12 #define _LINUX_MOUNT_H 13 #ifdef __KERNEL__ 14 15 #include <linux/types.h> 16 #include <linux/list.h> 17 #include <linux/spinlock.h> 18 #include <asm/atomic.h> 19 20 struct super_block; 21 struct vfsmount; 22 struct dentry; 23 struct mnt_namespace; 24 25 #define MNT_NOSUID 0x01 26 #define MNT_NODEV 0x02 27 #define MNT_NOEXEC 0x04 28 #define MNT_NOATIME 0x08 29 #define MNT_NODIRATIME 0x10 30 #define MNT_RELATIME 0x20 31 32 #define MNT_SHRINKABLE 0x100 33 34 #define MNT_SHARED 0x1000 /* if the vfsmount is a shared mount */ 35 #define MNT_UNBINDABLE 0x2000 /* if the vfsmount is a unbindable mount */ 36 #define MNT_PNODE_MASK 0x3000 /* propogation flag mask */ 37 38 struct vfsmount { 39 struct list_head mnt_hash; 40 struct vfsmount *mnt_parent; /* fs we are mounted on */ 41 struct dentry *mnt_mountpoint; /* dentry of mountpoint */ 42 struct dentry *mnt_root; /* root of the mounted tree */ 43 struct super_block *mnt_sb; /* pointer to superblock */ 44 struct list_head mnt_mounts; /* list of children, anchored here */ 45 struct list_head mnt_child; /* and going through their mnt_child */ 46 atomic_t mnt_count; 47 int mnt_flags; 48 int mnt_expiry_mark; /* true if marked for expiry */ 49 char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */ 50 struct list_head mnt_list; 51 struct list_head mnt_expire; /* link in fs-specific expiry list */ 52 struct list_head mnt_share; /* circular list of shared mounts */ 53 struct list_head mnt_slave_list;/* list of slave mounts */ 54 struct list_head mnt_slave; /* slave list entry */ 55 struct vfsmount *mnt_master; /* slave is on master->mnt_slave_list */ 56 struct mnt_namespace *mnt_ns; /* containing namespace */ 57 int mnt_pinned; 58 }; 59 60 static inline struct vfsmount *mntget(struct vfsmount *mnt) 61 { 62 if (mnt) 63 atomic_inc(&mnt->mnt_count); 64 return mnt; 65 } 66 67 extern void mntput_no_expire(struct vfsmount *mnt); 68 extern void mnt_pin(struct vfsmount *mnt); 69 extern void mnt_unpin(struct vfsmount *mnt); 70 71 static inline void mntput(struct vfsmount *mnt) 72 { 73 if (mnt) { 74 mnt->mnt_expiry_mark = 0; 75 mntput_no_expire(mnt); 76 } 77 } 78 79 extern void free_vfsmnt(struct vfsmount *mnt); 80 extern struct vfsmount *alloc_vfsmnt(const char *name); 81 extern struct vfsmount *do_kern_mount(const char *fstype, int flags, 82 const char *name, void *data); 83 84 struct file_system_type; 85 extern struct vfsmount *vfs_kern_mount(struct file_system_type *type, 86 int flags, const char *name, 87 void *data); 88 89 struct nameidata; 90 91 extern int do_add_mount(struct vfsmount *newmnt, struct nameidata *nd, 92 int mnt_flags, struct list_head *fslist); 93 94 extern void mark_mounts_for_expiry(struct list_head *mounts); 95 extern void shrink_submounts(struct vfsmount *mountpoint, struct list_head *mounts); 96 97 extern spinlock_t vfsmount_lock; 98 extern dev_t name_to_dev_t(char *name); 99 100 #endif 101 #endif /* _LINUX_MOUNT_H */ 102