fuse_i.h

Go to the documentation of this file.

/*
  FUSE: Filesystem in Userspace
  Copyright (C) 2001-2008  Miklos Szeredi <[email protected]>

  This program can be distributed under the terms of the GNU GPL.
  See the file COPYING.
*/

#ifndef _FS_FUSE_I_H
#define _FS_FUSE_I_H

#include <linux/fuse.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/wait.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/backing-dev.h>
#include <linux/mutex.h>
#include <linux/rwsem.h>
#include <linux/rbtree.h>
#include <linux/poll.h>
#include <linux/workqueue.h>

#define FUSE_MAX_PAGES_PER_REQ 32

#define FUSE_NOWRITE INT_MIN

#define FUSE_NAME_MAX 1024

#define FUSE_CTL_NUM_DENTRIES 5

#define FUSE_DEFAULT_PERMISSIONS (1 << 0)

#define FUSE_ALLOW_OTHER         (1 << 1)

extern struct list_head fuse_conn_list;

extern struct mutex fuse_mutex;

extern unsigned max_user_bgreq;
extern unsigned max_user_congthresh;

/* One forget request */
struct fuse_forget_link {
    struct fuse_forget_one forget_one;
    struct fuse_forget_link *next;
};

struct fuse_inode {
    struct inode inode;

    u64 nodeid;

    u64 nlookup;

    struct fuse_forget_link *forget;

    u64 i_time;

    umode_t orig_i_mode;

    u64 orig_ino;

    u64 attr_version;

    struct list_head write_files;

    struct list_head queued_writes;

    int writectr;

    wait_queue_head_t page_waitq;

    struct list_head writepages;
};

struct fuse_conn;

struct fuse_file {
    struct fuse_conn *fc;

    struct fuse_req *reserved_req;

    u64 kh;

    u64 fh;

    u64 nodeid;

    atomic_t count;

    u32 open_flags;

    struct list_head write_entry;

    struct rb_node polled_node;

    wait_queue_head_t poll_wait;

    bool flock:1;
};

struct fuse_in_arg {
    unsigned size;
    const void *value;
};

struct fuse_in {
    struct fuse_in_header h;

    unsigned argpages:1;

    unsigned numargs;

    struct fuse_in_arg args[3];
};

struct fuse_arg {
    unsigned size;
    void *value;
};

struct fuse_out {
    struct fuse_out_header h;

    /*
     * The following bitfields are not changed during the request
     * processing
     */

    unsigned argvar:1;

    unsigned argpages:1;

    unsigned page_zeroing:1;

    unsigned page_replace:1;

    unsigned numargs;

    struct fuse_arg args[3];
};

enum fuse_req_state {
    FUSE_REQ_INIT = 0,
    FUSE_REQ_PENDING,
    FUSE_REQ_READING,
    FUSE_REQ_SENT,
    FUSE_REQ_WRITING,
    FUSE_REQ_FINISHED
};

struct fuse_req {
    struct list_head list;

    struct list_head intr_entry;

    atomic_t count;

    u64 intr_unique;

    /*
     * The following bitfields are either set once before the
     * request is queued or setting/clearing them is protected by
     * fuse_conn->lock
     */

    unsigned isreply:1;

    unsigned force:1;

    unsigned aborted:1;

    unsigned background:1;

    unsigned interrupted:1;

    unsigned locked:1;

    unsigned waiting:1;

    enum fuse_req_state state;

    struct fuse_in in;

    struct fuse_out out;

    wait_queue_head_t waitq;

    union {
        struct {
            union {
                struct fuse_release_in in;
                struct work_struct work;
            };
            struct path path;
        } release;
        struct fuse_init_in init_in;
        struct fuse_init_out init_out;
        struct cuse_init_in cuse_init_in;
        struct {
            struct fuse_read_in in;
            u64 attr_ver;
        } read;
        struct {
            struct fuse_write_in in;
            struct fuse_write_out out;
        } write;
        struct fuse_notify_retrieve_in retrieve_in;
        struct fuse_lk_in lk_in;
    } misc;

    struct page *pages[FUSE_MAX_PAGES_PER_REQ];

    unsigned num_pages;

    unsigned page_offset;

    struct fuse_file *ff;

    struct inode *inode;

    struct list_head writepages_entry;

    void (*end)(struct fuse_conn *, struct fuse_req *);

    struct file *stolen_file;
};

struct fuse_conn {
    spinlock_t lock;

    struct mutex inst_mutex;

    atomic_t count;

    uid_t user_id;

    gid_t group_id;

    unsigned flags;

    unsigned max_read;

    unsigned max_write;

    wait_queue_head_t waitq;

    struct list_head pending;

    struct list_head processing;

    struct list_head io;

    u64 khctr;

    struct rb_root polled_files;

    unsigned max_background;

    unsigned congestion_threshold;

    unsigned num_background;

    unsigned active_background;

    struct list_head bg_queue;

    struct list_head interrupts;

    struct fuse_forget_link forget_list_head;
    struct fuse_forget_link *forget_list_tail;

    int forget_batch;

    int blocked;

    wait_queue_head_t blocked_waitq;

    wait_queue_head_t reserved_req_waitq;

    u64 reqctr;

    unsigned connected;

    unsigned conn_error:1;

    unsigned conn_init:1;

    unsigned async_read:1;

    unsigned atomic_o_trunc:1;

    unsigned export_support:1;

    unsigned bdi_initialized:1;

    /*
     * The following bitfields are only for optimization purposes
     * and hence races in setting them will not cause malfunction
     */

    unsigned no_fsync:1;

    unsigned no_fsyncdir:1;

    unsigned no_flush:1;

    unsigned no_setxattr:1;

    unsigned no_getxattr:1;

    unsigned no_listxattr:1;

    unsigned no_removexattr:1;

    unsigned no_lock:1;

    unsigned no_access:1;

    unsigned no_create:1;

    unsigned no_interrupt:1;

    unsigned no_bmap:1;

    unsigned no_poll:1;

    unsigned big_writes:1;

    unsigned dont_mask:1;

    unsigned no_flock:1;

    unsigned no_fallocate:1;

    unsigned auto_inval_data:1;

    atomic_t num_waiting;

    unsigned minor;

    struct backing_dev_info bdi;

    struct list_head entry;

    dev_t dev;

    struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];

    int ctl_ndents;

    struct fasync_struct *fasync;

    u32 scramble_key[4];

    struct fuse_req *destroy_req;

    u64 attr_version;

    void (*release)(struct fuse_conn *);

    struct super_block *sb;

    struct rw_semaphore killsb;
};

static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
{
    return sb->s_fs_info;
}

static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
{
    return get_fuse_conn_super(inode->i_sb);
}

static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
{
    return container_of(inode, struct fuse_inode, inode);
}

static inline u64 get_node_id(struct inode *inode)
{
    return get_fuse_inode(inode)->nodeid;
}

extern const struct file_operations fuse_dev_operations;

extern const struct dentry_operations fuse_dentry_operations;

int fuse_inode_eq(struct inode *inode, void *_nodeidp);

struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
            int generation, struct fuse_attr *attr,
            u64 attr_valid, u64 attr_version);

int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
             struct fuse_entry_out *outarg, struct inode **inode);

void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
               u64 nodeid, u64 nlookup);

struct fuse_forget_link *fuse_alloc_forget(void);

void fuse_read_fill(struct fuse_req *req, struct file *file,
            loff_t pos, size_t count, int opcode);

int fuse_open_common(struct inode *inode, struct file *file, bool isdir);

struct fuse_file *fuse_file_alloc(struct fuse_conn *fc);
struct fuse_file *fuse_file_get(struct fuse_file *ff);
void fuse_file_free(struct fuse_file *ff);
void fuse_finish_open(struct inode *inode, struct file *file);

void fuse_sync_release(struct fuse_file *ff, int flags);

void fuse_release_common(struct file *file, int opcode);

int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
              int datasync, int isdir);

int fuse_notify_poll_wakeup(struct fuse_conn *fc,
                struct fuse_notify_poll_wakeup_out *outarg);

void fuse_init_file_inode(struct inode *inode);

void fuse_init_common(struct inode *inode);

void fuse_init_dir(struct inode *inode);

void fuse_init_symlink(struct inode *inode);

void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
                u64 attr_valid, u64 attr_version);

void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
                   u64 attr_valid);

int fuse_dev_init(void);

void fuse_dev_cleanup(void);

int fuse_ctl_init(void);
void fuse_ctl_cleanup(void);

struct fuse_req *fuse_request_alloc(void);

struct fuse_req *fuse_request_alloc_nofs(void);

void fuse_request_free(struct fuse_req *req);

struct fuse_req *fuse_get_req(struct fuse_conn *fc);

struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file);

void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);

void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req);

void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req);

void fuse_request_send_background_locked(struct fuse_conn *fc,
                     struct fuse_req *req);

/* Abort all requests */
void fuse_abort_conn(struct fuse_conn *fc);

void fuse_invalidate_attr(struct inode *inode);

void fuse_invalidate_entry_cache(struct dentry *entry);

struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);

void fuse_conn_kill(struct fuse_conn *fc);

void fuse_conn_init(struct fuse_conn *fc);

void fuse_conn_put(struct fuse_conn *fc);

int fuse_ctl_add_conn(struct fuse_conn *fc);

void fuse_ctl_remove_conn(struct fuse_conn *fc);

int fuse_valid_type(int m);

int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task);

u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);

int fuse_update_attributes(struct inode *inode, struct kstat *stat,
               struct file *file, bool *refreshed);

void fuse_flush_writepages(struct inode *inode);

void fuse_set_nowrite(struct inode *inode);
void fuse_release_nowrite(struct inode *inode);

u64 fuse_get_attr_version(struct fuse_conn *fc);

int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
                 loff_t offset, loff_t len);

int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
                 u64 child_nodeid, struct qstr *name);

int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
         bool isdir);
ssize_t fuse_direct_io(struct file *file, const char __user *buf,
               size_t count, loff_t *ppos, int write);
long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
           unsigned int flags);
long fuse_ioctl_common(struct file *file, unsigned int cmd,
               unsigned long arg, unsigned int flags);
unsigned fuse_file_poll(struct file *file, poll_table *wait);
int fuse_dev_release(struct inode *inode, struct file *file);

void fuse_write_update_size(struct inode *inode, loff_t pos);

#endif /* _FS_FUSE_I_H */