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Diffstat (limited to 'include/linux/mount.h')
| -rw-r--r-- | include/linux/mount.h | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/include/linux/mount.h b/include/linux/mount.h new file mode 100644 index 00000000000..5d527536486 --- /dev/null +++ b/include/linux/mount.h @@ -0,0 +1,129 @@ +/* + * + * Definitions for mount interface. This describes the in the kernel build + * linkedlist with mounted filesystems. + * + * Author: Marco van Wieringen <mvw@planets.elm.net> + * + */ +#ifndef _LINUX_MOUNT_H +#define _LINUX_MOUNT_H + +#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_STRICTATIME 0x80 + +#define MNT_SHRINKABLE 0x100 +#define MNT_WRITE_HOLD 0x200 + +#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 */ + const 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 */ + int mnt_id; /* mount identifier */ + int mnt_group_id; /* peer group identifier */ + /* + * 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; +#ifdef CONFIG_SMP + int *mnt_writers; +#else + int mnt_writers; +#endif +}; + +static inline int *get_mnt_writers_ptr(struct vfsmount *mnt) +{ +#ifdef CONFIG_SMP + return mnt->mnt_writers; +#else + return &mnt->mnt_writers; +#endif +} + +static inline struct vfsmount *mntget(struct vfsmount *mnt) +{ + if (mnt) + atomic_inc(&mnt->mnt_count); + return mnt; +} + +struct file; /* forward dec */ + +extern int mnt_want_write(struct vfsmount *mnt); +extern int mnt_want_write_file(struct file *file); +extern int mnt_clone_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; + +struct path; +extern int do_add_mount(struct vfsmount *newmnt, struct path *path, + 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 /* _LINUX_MOUNT_H */ |