fs/mount.h

   1 #include <linux/mount.h>
   2 #include <linux/seq_file.h>
   3 #include <linux/poll.h>
   4
   5 struct mnt_namespace {
   6         atomic_t                count;
   7         struct mount *  root;
   8         struct list_head        list;
   9         wait_queue_head_t poll;
  10         int event;
  11 };
  12
  13 struct mnt_pcp {
  14         int mnt_count;
  15         int mnt_writers;
  16 };
  17
  18 struct mount {
  19         struct list_head mnt_hash;
  20         struct mount *mnt_parent;
  21         struct dentry *mnt_mountpoint;
  22         struct vfsmount mnt;
  23 #ifdef CONFIG_SMP
  24         struct mnt_pcp __percpu *mnt_pcp;
  25 #else
  26         int mnt_count;
  27         int mnt_writers;
  28 #endif
  29         struct list_head mnt_mounts;    /* list of children, anchored here */
  30         struct list_head mnt_child;     /* and going through their mnt_child */
  31         struct list_head mnt_instance;  /* mount instance on sb->s_mounts */
  32         const char *mnt_devname;        /* Name of device e.g. /dev/dsk/hda1 */
  33         struct list_head mnt_list;
  34         struct list_head mnt_expire;    /* link in fs-specific expiry list */
  35         struct list_head mnt_share;     /* circular list of shared mounts */
  36         struct list_head mnt_slave_list;/* list of slave mounts */
  37         struct list_head mnt_slave;     /* slave list entry */
  38         struct mount *mnt_master;       /* slave is on master->mnt_slave_list */
  39         struct mnt_namespace *mnt_ns;   /* containing namespace */
  40 #ifdef CONFIG_FSNOTIFY
  41         struct hlist_head mnt_fsnotify_marks;
  42         __u32 mnt_fsnotify_mask;
  43 #endif
  44         int mnt_id;                     /* mount identifier */
  45         int mnt_group_id;               /* peer group identifier */
  46         int mnt_expiry_mark;            /* true if marked for expiry */
  47         int mnt_pinned;
  48         int mnt_ghosts;
  49 };
  50
  51 #define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
  52
  53 static inline struct mount *real_mount(struct vfsmount *mnt)
  54 {
  55         return container_of(mnt, struct mount, mnt);
  56 }
  57
  58 static inline int mnt_has_parent(struct mount *mnt)
  59 {
  60         return mnt != mnt->mnt_parent;
  61 }
  62
  63 static inline int is_mounted(struct vfsmount *mnt)
  64 {
  65         /* neither detached nor internal? */
  66         return !IS_ERR_OR_NULL(real_mount(mnt));
  67 }
  68
  69 extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *, int);
  70
  71 static inline void get_mnt_ns(struct mnt_namespace *ns)
  72 {
  73         atomic_inc(&ns->count);
  74 }
  75
  76 struct proc_mounts {
  77         struct seq_file m;
  78         struct mnt_namespace *ns;
  79         struct path root;
  80         int (*show)(struct seq_file *, struct vfsmount *);
  81 };
  82
  83 #define proc_mounts(p) (container_of((p), struct proc_mounts, m))
  84
  85 extern const struct seq_operations mounts_op;