| /* |
| * |
| * Definitions for mount interface. This describes the in the kernel build |
| * linkedlist with mounted filesystems. |
| * |
| * Author: Marco van Wieringen <mvw@planets.elm.net> |
| * |
| * Version: $Id: mount.h,v 2.0 1996/11/17 16:48:14 mvw Exp mvw $ |
| * |
| */ |
| #ifndef _LINUX_MOUNT_H |
| #define _LINUX_MOUNT_H |
| #ifdef __KERNEL__ |
| |
| #include <linux/types.h> |
| #include <linux/list.h> |
| #include <linux/nodemask.h> |
| #include <linux/spinlock.h> |
| #include <asm/atomic.h> |
| |
| struct super_block; |
| struct vfsmount; |
| struct dentry; |
| struct mnt_namespace; |
| |
| #define MNT_NOSUID 0x01 |
| #define MNT_NODEV 0x02 |
| #define MNT_NOEXEC 0x04 |
| #define MNT_NOATIME 0x08 |
| #define MNT_NODIRATIME 0x10 |
| #define MNT_RELATIME 0x20 |
| #define MNT_READONLY 0x40 /* does the user want this to be r/o? */ |
| |
| #define MNT_SHRINKABLE 0x100 |
| #define MNT_IMBALANCED_WRITE_COUNT 0x200 /* just for debugging */ |
| |
| #define MNT_SHARED 0x1000 /* if the vfsmount is a shared mount */ |
| #define MNT_UNBINDABLE 0x2000 /* if the vfsmount is a unbindable mount */ |
| #define MNT_PNODE_MASK 0x3000 /* propagation flag mask */ |
| |
| struct vfsmount { |
| struct list_head mnt_hash; |
| struct vfsmount *mnt_parent; /* fs we are mounted on */ |
| struct dentry *mnt_mountpoint; /* dentry of mountpoint */ |
| struct dentry *mnt_root; /* root of the mounted tree */ |
| struct super_block *mnt_sb; /* pointer to superblock */ |
| struct list_head mnt_mounts; /* list of children, anchored here */ |
| struct list_head mnt_child; /* and going through their mnt_child */ |
| int mnt_flags; |
| /* 4 bytes hole on 64bits arches */ |
| char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */ |
| struct list_head mnt_list; |
| struct list_head mnt_expire; /* link in fs-specific expiry list */ |
| struct list_head mnt_share; /* circular list of shared mounts */ |
| struct list_head mnt_slave_list;/* list of slave mounts */ |
| struct list_head mnt_slave; /* slave list entry */ |
| struct vfsmount *mnt_master; /* slave is on master->mnt_slave_list */ |
| struct mnt_namespace *mnt_ns; /* containing namespace */ |
| /* |
| * We put mnt_count & mnt_expiry_mark at the end of struct vfsmount |
| * to let these frequently modified fields in a separate cache line |
| * (so that reads of mnt_flags wont ping-pong on SMP machines) |
| */ |
| atomic_t mnt_count; |
| int mnt_expiry_mark; /* true if marked for expiry */ |
| int mnt_pinned; |
| int mnt_ghosts; |
| /* |
| * This value is not stable unless all of the mnt_writers[] spinlocks |
| * are held, and all mnt_writer[]s on this mount have 0 as their ->count |
| */ |
| atomic_t __mnt_writers; |
| }; |
| |
| static inline struct vfsmount *mntget(struct vfsmount *mnt) |
| { |
| if (mnt) |
| atomic_inc(&mnt->mnt_count); |
| return mnt; |
| } |
| |
| extern int mnt_want_write(struct vfsmount *mnt); |
| extern void mnt_drop_write(struct vfsmount *mnt); |
| extern void mntput_no_expire(struct vfsmount *mnt); |
| extern void mnt_pin(struct vfsmount *mnt); |
| extern void mnt_unpin(struct vfsmount *mnt); |
| extern int __mnt_is_readonly(struct vfsmount *mnt); |
| |
| static inline void mntput(struct vfsmount *mnt) |
| { |
| if (mnt) { |
| mnt->mnt_expiry_mark = 0; |
| mntput_no_expire(mnt); |
| } |
| } |
| |
| extern struct vfsmount *do_kern_mount(const char *fstype, int flags, |
| const char *name, void *data); |
| |
| struct file_system_type; |
| extern struct vfsmount *vfs_kern_mount(struct file_system_type *type, |
| int flags, const char *name, |
| void *data); |
| |
| struct nameidata; |
| |
| extern int do_add_mount(struct vfsmount *newmnt, struct nameidata *nd, |
| int mnt_flags, struct list_head *fslist); |
| |
| extern void mark_mounts_for_expiry(struct list_head *mounts); |
| |
| extern spinlock_t vfsmount_lock; |
| extern dev_t name_to_dev_t(char *name); |
| |
| #endif |
| #endif /* _LINUX_MOUNT_H */ |