/*
FUSE: Filesystem in Userspace
- Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu>
+ Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu>
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
#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 <asm/semaphore.h>
+#include <linux/mutex.h>
/** Max number of pages that can be used in a single read request */
#define FUSE_MAX_PAGES_PER_REQ 32
-/** If more requests are outstanding, then the operation will block */
-#define FUSE_MAX_OUTSTANDING 10
+/** Maximum number of outstanding background requests */
+#define FUSE_MAX_BACKGROUND 10
/** It could be as large as PATH_MAX, but would that have any uses? */
#define FUSE_NAME_MAX 1024
+/** Number of dentries for each connection in the control filesystem */
+#define FUSE_CTL_NUM_DENTRIES 3
+
/** If the FUSE_DEFAULT_PERMISSIONS flag is given, the filesystem
module will check permissions based on the file mode. Otherwise no
permission checking is done in the kernel */
doing the mount will be allowed to access the filesystem */
#define FUSE_ALLOW_OTHER (1 << 1)
+/** List of active connections */
+extern struct list_head fuse_conn_list;
+
+/** Global mutex protecting fuse_conn_list and the control filesystem */
+extern struct mutex fuse_mutex;
/** FUSE inode */
struct fuse_inode {
struct fuse_req *forget_req;
/** Time in jiffies until the file attributes are valid */
- unsigned long i_time;
+ u64 i_time;
};
/** FUSE specific file data */
struct fuse_file {
/** Request reserved for flush and release */
- struct fuse_req *release_req;
+ struct fuse_req *reserved_req;
/** File handle used by userspace */
u64 fh;
FUSE_REQ_PENDING,
FUSE_REQ_READING,
FUSE_REQ_SENT,
+ FUSE_REQ_WRITING,
FUSE_REQ_FINISHED
};
* A request to the client
*/
struct fuse_req {
- /** This can be on either unused_list, pending processing or
- io lists in fuse_conn */
+ /** This can be on either pending processing or io lists in
+ fuse_conn */
struct list_head list;
- /** Entry on the background list */
- struct list_head bg_entry;
+ /** Entry on the interrupts list */
+ struct list_head intr_entry;
/** refcount */
atomic_t count;
+ /** Unique ID for the interrupt request */
+ u64 intr_unique;
+
/*
* The following bitfields are either set once before the
* request is queued or setting/clearing them is protected by
- * fuse_lock
+ * fuse_conn->lock
*/
/** True if the request has reply */
unsigned isreply:1;
- /** The request is preallocated */
- unsigned preallocated:1;
+ /** Force sending of the request even if interrupted */
+ unsigned force:1;
- /** The request was interrupted */
- unsigned interrupted:1;
+ /** The request was aborted */
+ unsigned aborted:1;
/** Request is sent in the background */
unsigned background:1;
+ /** The request has been interrupted */
+ unsigned interrupted:1;
+
/** Data is being copied to/from the request */
unsigned locked:1;
+ /** Request is counted as "waiting" */
+ unsigned waiting:1;
+
/** State of the request */
enum fuse_req_state state;
struct fuse_init_in init_in;
struct fuse_init_out init_out;
struct fuse_read_in read_in;
+ struct fuse_lk_in lk_in;
} misc;
/** page vector */
/** offset of data on first page */
unsigned page_offset;
- /** Inode used in the request */
- struct inode *inode;
-
- /** Second inode used in the request (or NULL) */
- struct inode *inode2;
-
/** File used in the request (or NULL) */
struct file *file;
+ /** vfsmount used in release */
+ struct vfsmount *vfsmount;
+
+ /** dentry used in release */
+ struct dentry *dentry;
+
/** Request completion callback */
void (*end)(struct fuse_conn *, struct fuse_req *);
+
+ /** Request is stolen from fuse_file->reserved_req */
+ struct file *stolen_file;
};
/**
* unmounted.
*/
struct fuse_conn {
+ /** Lock protecting accessess to members of this structure */
+ spinlock_t lock;
+
+ /** Mutex protecting against directory alias creation */
+ struct mutex inst_mutex;
+
+ /** Refcount */
+ atomic_t count;
+
/** The user id for this mount */
uid_t user_id;
/** The list of requests under I/O */
struct list_head io;
- /** Requests put in the background (RELEASE or any other
- interrupted request) */
- struct list_head background;
+ /** Number of requests currently in the background */
+ unsigned num_background;
- /** Controls the maximum number of outstanding requests */
- struct semaphore outstanding_sem;
+ /** Pending interrupts */
+ struct list_head interrupts;
- /** This counts the number of outstanding requests if
- outstanding_sem would go negative */
- unsigned outstanding_debt;
+ /** Flag indicating if connection is blocked. This will be
+ the case before the INIT reply is received, and if there
+ are too many outstading backgrounds requests */
+ int blocked;
- /** RW semaphore for exclusion with fuse_put_super() */
- struct rw_semaphore sbput_sem;
-
- /** The list of unused requests */
- struct list_head unused_list;
+ /** waitq for blocked connection */
+ wait_queue_head_t blocked_waitq;
/** The next unique request id */
u64 reqctr;
- /** Mount is active */
- unsigned mounted;
-
/** Connection established, cleared on umount, connection
abort and device release */
unsigned connected;
reply, before any other request, and never cleared */
unsigned conn_error : 1;
+ /** Do readpages asynchronously? Only set in INIT */
+ unsigned async_read : 1;
+
/*
* The following bitfields are only for optimization purposes
* and hence races in setting them will not cause malfunction
/** Is removexattr not implemented by fs? */
unsigned no_removexattr : 1;
+ /** Are file locking primitives not implemented by fs? */
+ unsigned no_lock : 1;
+
/** Is access not implemented by fs? */
unsigned no_access : 1;
/** Is create not implemented by fs? */
unsigned no_create : 1;
+ /** Is interrupt not implemented by fs? */
+ unsigned no_interrupt : 1;
+
/** The number of requests waiting for completion */
atomic_t num_waiting;
/** Backing dev info */
struct backing_dev_info bdi;
- /** kobject */
- struct kobject kobj;
+ /** Entry on the fuse_conn_list */
+ struct list_head entry;
+
+ /** Unique ID */
+ u64 id;
+
+ /** Dentries in the control filesystem */
+ struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];
+
+ /** number of dentries used in the above array */
+ int ctl_ndents;
+
+ /** O_ASYNC requests */
+ struct fasync_struct *fasync;
+
+ /** Key for lock owner ID scrambling */
+ u32 scramble_key[4];
};
static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
return get_fuse_conn_super(inode->i_sb);
}
-static inline struct fuse_conn *get_fuse_conn_kobj(struct kobject *obj)
-{
- return container_of(obj, struct fuse_conn, kobj);
-}
-
static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
{
return container_of(inode, struct fuse_inode, inode);
}
/** Device operations */
-extern struct file_operations fuse_dev_operations;
-
-/**
- * This is the single global spinlock which protects FUSE's structures
- *
- * The following data is protected by this lock:
- *
- * - the private_data field of the device file
- * - the s_fs_info field of the super block
- * - unused_list, pending, processing lists in fuse_conn
- * - background list in fuse_conn
- * - the unique request ID counter reqctr in fuse_conn
- * - the sb (super_block) field in fuse_conn
- * - the file (device file) field in fuse_conn
- */
-extern spinlock_t fuse_lock;
+extern const struct file_operations fuse_dev_operations;
/**
* Get a filled in inode
void fuse_finish_open(struct inode *inode, struct file *file,
struct fuse_file *ff, struct fuse_open_out *outarg);
-/**
- * Send a RELEASE request
- */
-void fuse_send_release(struct fuse_conn *fc, struct fuse_file *ff,
- u64 nodeid, struct inode *inode, int flags, int isdir);
-
+/** */
+struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags,
+ int opcode);
/**
* Send RELEASE or RELEASEDIR request
*/
*/
void fuse_dev_cleanup(void);
+int fuse_ctl_init(void);
+void fuse_ctl_cleanup(void);
+
/**
* Allocate a request
*/
void fuse_request_free(struct fuse_req *req);
/**
- * Reinitialize a request, the preallocated flag is left unmodified
+ * Get a request, may fail with -ENOMEM
*/
-void fuse_reset_request(struct fuse_req *req);
+struct fuse_req *fuse_get_req(struct fuse_conn *fc);
/**
- * Reserve a preallocated request
+ * Gets a requests for a file operation, always succeeds
*/
-struct fuse_req *fuse_get_request(struct fuse_conn *fc);
+struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file);
/**
- * Decrement reference count of a request. If count goes to zero put
- * on unused list (preallocated) or free request (not preallocated).
+ * Decrement reference count of a request. If count goes to zero free
+ * the request.
*/
void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);
*/
void request_send_background(struct fuse_conn *fc, struct fuse_req *req);
-/**
- * Release inodes and file associated with background request
- */
-void fuse_release_background(struct fuse_req *req);
-
/* Abort all requests */
void fuse_abort_conn(struct fuse_conn *fc);
* Invalidate inode attributes
*/
void fuse_invalidate_attr(struct inode *inode);
+
+/**
+ * Acquire reference to fuse_conn
+ */
+struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
+
+/**
+ * Release reference to fuse_conn
+ */
+void fuse_conn_put(struct fuse_conn *fc);
+
+/**
+ * Add connection to control filesystem
+ */
+int fuse_ctl_add_conn(struct fuse_conn *fc);
+
+/**
+ * Remove connection from control filesystem
+ */
+void fuse_ctl_remove_conn(struct fuse_conn *fc);