/*
FUSE: Filesystem in Userspace
- Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu>
+ Copyright (C) 2001-2005 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 <linux/mutex.h>
+#include <asm/semaphore.h>
/** Max number of pages that can be used in a single read request */
#define FUSE_MAX_PAGES_PER_REQ 32
-/** Maximum number of outstanding background requests */
-#define FUSE_MAX_BACKGROUND 10
+/** If more requests are outstanding, then the operation will block */
+#define FUSE_MAX_OUTSTANDING 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 */
- u64 i_time;
+ unsigned long i_time;
};
/** FUSE specific file data */
struct fuse_file {
/** Request reserved for flush and release */
- struct fuse_req *reserved_req;
+ struct fuse_req *release_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 pending processing or io lists in
- fuse_conn */
+ /** This can be on either unused_list, pending processing or
+ io lists in fuse_conn */
struct list_head list;
- /** Entry on the interrupts list */
- struct list_head intr_entry;
+ /** Entry on the background list */
+ struct list_head bg_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_conn->lock
+ * fuse_lock
*/
/** True if the request has reply */
unsigned isreply:1;
- /** Force sending of the request even if interrupted */
- unsigned force:1;
+ /** The request is preallocated */
+ unsigned preallocated:1;
- /** The request was aborted */
- unsigned aborted:1;
+ /** The request was interrupted */
+ unsigned interrupted: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;
- /** File used in the request (or NULL) */
- struct file *file;
+ /** Inode used in the request */
+ struct inode *inode;
- /** vfsmount used in release */
- struct vfsmount *vfsmount;
+ /** Second inode used in the request (or NULL) */
+ struct inode *inode2;
- /** dentry used in release */
- struct dentry *dentry;
+ /** File used in the request (or NULL) */
+ struct file *file;
/** 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;
-
- /** 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;
- /** Number of requests currently in the background */
- unsigned num_background;
+ /** Requests put in the background (RELEASE or any other
+ interrupted request) */
+ struct list_head background;
- /** Pending interrupts */
- struct list_head interrupts;
+ /** Controls the maximum number of outstanding requests */
+ struct semaphore outstanding_sem;
- /** 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;
+ /** This counts the number of outstanding requests if
+ outstanding_sem would go negative */
+ unsigned outstanding_debt;
- /** waitq for blocked connection */
- wait_queue_head_t blocked_waitq;
+ /** RW semaphore for exclusion with fuse_put_super() */
+ struct rw_semaphore sbput_sem;
+
+ /** The list of unused requests */
+ struct list_head unused_list;
/** The next unique request id */
u64 reqctr;
+ /** Mount is active */
+ unsigned mounted;
+
/** Connection established, cleared on umount, connection
abort and device release */
unsigned connected;
/** 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;
- /** 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];
+ /** kobject */
+ struct kobject kobj;
};
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 const struct file_operations fuse_dev_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;
/**
* Get a filled in inode
void fuse_finish_open(struct inode *inode, struct file *file,
struct fuse_file *ff, struct fuse_open_out *outarg);
-/** */
-struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags,
- int opcode);
+/**
+ * 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);
+
/**
* 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);
/**
- * Get a request, may fail with -ENOMEM
+ * Reinitialize a request, the preallocated flag is left unmodified
*/
-struct fuse_req *fuse_get_req(struct fuse_conn *fc);
+void fuse_reset_request(struct fuse_req *req);
/**
- * Gets a requests for a file operation, always succeeds
+ * Reserve a preallocated request
*/
-struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file);
+struct fuse_req *fuse_get_request(struct fuse_conn *fc);
/**
- * Decrement reference count of a request. If count goes to zero free
- * the request.
+ * Decrement reference count of a request. If count goes to zero put
+ * on unused list (preallocated) or free request (not preallocated).
*/
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);
git://git.onelab.eu / linux-2.6.git / blobdiff