/*
FUSE: Filesystem in Userspace
- Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu>
+ Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
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 <asm/semaphore.h>
+#include <linux/mutex.h>
+#include <linux/rwsem.h>
+#include <linux/rbtree.h>
+#include <linux/poll.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
+/** Bias for fi->writectr, meaning new writepages must not be sent */
+#define FUSE_NOWRITE INT_MIN
+
+/** 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 5
/** If the FUSE_DEFAULT_PERMISSIONS flag is given, the filesystem
module will check permissions based on the file mode. Otherwise no
doing the mount will be allowed to access the filesystem */
#define FUSE_ALLOW_OTHER (1 << 1)
-/** If the FUSE_KERNEL_CACHE flag is given, then cached data will not
- be flushed on open */
-#define FUSE_KERNEL_CACHE (1 << 2)
+/** List of active connections */
+extern struct list_head fuse_conn_list;
-/** Bypass the page cache for read and write operations */
-#define FUSE_DIRECT_IO (1 << 3)
+/** Global mutex protecting fuse_conn_list and the control filesystem */
+extern struct mutex fuse_mutex;
+
+/** Module parameters */
+extern unsigned max_user_bgreq;
+extern unsigned max_user_congthresh;
/** 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;
+
+ /** The sticky bit in inode->i_mode may have been removed, so
+ preserve the original mode */
+ mode_t orig_i_mode;
+
+ /** Version of last attribute change */
+ u64 attr_version;
+
+ /** Files usable in writepage. Protected by fc->lock */
+ struct list_head write_files;
+
+ /** Writepages pending on truncate or fsync */
+ struct list_head queued_writes;
+
+ /** Number of sent writes, a negative bias (FUSE_NOWRITE)
+ * means more writes are blocked */
+ int writectr;
+
+ /** Waitq for writepage completion */
+ wait_queue_head_t page_waitq;
+
+ /** List of writepage requestst (pending or sent) */
+ struct list_head writepages;
};
+struct fuse_conn;
+
/** FUSE specific file data */
struct fuse_file {
+ /** Fuse connection for this file */
+ struct fuse_conn *fc;
+
/** Request reserved for flush and release */
- struct fuse_req *release_req;
+ struct fuse_req *reserved_req;
+
+ /** Kernel file handle guaranteed to be unique */
+ u64 kh;
/** File handle used by userspace */
u64 fh;
+
+ /** Node id of this file */
+ u64 nodeid;
+
+ /** Refcount */
+ atomic_t count;
+
+ /** FOPEN_* flags returned by open */
+ u32 open_flags;
+
+ /** Entry on inode's write_files list */
+ struct list_head write_entry;
+
+ /** RB node to be linked on fuse_conn->polled_files */
+ struct rb_node polled_node;
+
+ /** Wait queue head for poll */
+ wait_queue_head_t poll_wait;
};
/** One input argument of a request */
/** Header returned from userspace */
struct fuse_out_header h;
+ /*
+ * The following bitfields are not changed during the request
+ * processing
+ */
+
/** Last argument is variable length (can be shorter than
arg->size) */
unsigned argvar:1;
struct fuse_arg args[3];
};
-struct fuse_req;
-struct fuse_conn;
+/** The request state */
+enum fuse_req_state {
+ FUSE_REQ_INIT = 0,
+ 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 or processing
- 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_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 has been sent to userspace */
- unsigned sent:1;
+ /** Request is counted as "waiting" */
+ unsigned waiting:1;
- /** The request is finished */
- unsigned finished:1;
+ /** State of the request */
+ enum fuse_req_state state;
/** The request input */
struct fuse_in in;
/** Data for asynchronous requests */
union {
struct fuse_forget_in forget_in;
- struct fuse_release_in release_in;
- struct fuse_init_in_out init_in_out;
+ struct {
+ struct fuse_release_in in;
+ struct path path;
+ } release;
+ struct fuse_init_in init_in;
+ struct fuse_init_out init_out;
+ struct cuse_init_in cuse_init_in;
+ struct cuse_init_out cuse_init_out;
+ struct {
+ struct fuse_read_in in;
+ u64 attr_ver;
+ } read;
+ struct {
+ struct fuse_write_in in;
+ struct fuse_write_out out;
+ } write;
+ struct fuse_lk_in lk_in;
} misc;
/** page vector */
/** offset of data on first page */
unsigned page_offset;
- /** Inode used in the request */
+ /** File used in the request (or NULL) */
+ struct fuse_file *ff;
+
+ /** Inode used in the request or NULL */
struct inode *inode;
- /** Second inode used in the request (or NULL) */
- struct inode *inode2;
+ /** Link on fi->writepages */
+ struct list_head writepages_entry;
- /** 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 {
- /** Reference count */
- int count;
+ /** 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 being processed */
struct list_head processing;
- /** Requests put in the background (RELEASE or any other
- interrupted request) */
- struct list_head background;
+ /** The list of requests under I/O */
+ struct list_head io;
+
+ /** The next unique kernel file handle */
+ u64 khctr;
+
+ /** rbtree of fuse_files waiting for poll events indexed by ph */
+ struct rb_root polled_files;
+
+ /** Maximum number of outstanding background requests */
+ unsigned max_background;
+
+ /** Number of background requests at which congestion starts */
+ unsigned congestion_threshold;
- /** Controls the maximum number of outstanding requests */
- struct semaphore outstanding_sem;
+ /** Number of requests currently in the background */
+ unsigned num_background;
- /** This counts the number of outstanding requests if
- outstanding_sem would go negative */
- unsigned outstanding_debt;
+ /** Number of background requests currently queued for userspace */
+ unsigned active_background;
- /** RW semaphore for exclusion with fuse_put_super() */
- struct rw_semaphore sbput_sem;
+ /** The list of background requests set aside for later queuing */
+ struct list_head bg_queue;
- /** The list of unused requests */
- struct list_head unused_list;
+ /** Pending interrupts */
+ struct list_head interrupts;
+
+ /** 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;
+
+ /** waitq for blocked connection */
+ wait_queue_head_t blocked_waitq;
+
+ /** waitq for reserved requests */
+ wait_queue_head_t reserved_req_waitq;
/** The next unique request id */
u64 reqctr;
- /** Mount is active */
- unsigned mounted : 1;
+ /** Connection established, cleared on umount, connection
+ abort and device release */
+ unsigned connected;
+
+ /** Connection failed (version mismatch). Cannot race with
+ setting other bitfields since it is only set once in INIT
+ reply, before any other request, and never cleared */
+ unsigned conn_error:1;
+
+ /** Connection successful. Only set in INIT */
+ unsigned conn_init:1;
+
+ /** Do readpages asynchronously? Only set in INIT */
+ unsigned async_read:1;
+
+ /** Do not send separate SETATTR request before open(O_TRUNC) */
+ unsigned atomic_o_trunc:1;
+
+ /** Filesystem supports NFS exporting. Only set in INIT */
+ unsigned export_support:1;
- /** Connection established */
- unsigned connected : 1;
+ /** Set if bdi is valid */
+ unsigned bdi_initialized:1;
- /** Connection failed (version mismatch) */
- unsigned conn_error : 1;
+ /*
+ * The following bitfields are only for optimization purposes
+ * and hence races in setting them will not cause malfunction
+ */
/** Is fsync not implemented by fs? */
- unsigned no_fsync : 1;
+ unsigned no_fsync:1;
+
+ /** Is fsyncdir not implemented by fs? */
+ unsigned no_fsyncdir:1;
/** Is flush not implemented by fs? */
- unsigned no_flush : 1;
+ unsigned no_flush:1;
/** Is setxattr not implemented by fs? */
- unsigned no_setxattr : 1;
+ unsigned no_setxattr:1;
/** Is getxattr not implemented by fs? */
- unsigned no_getxattr : 1;
+ unsigned no_getxattr:1;
/** Is listxattr not implemented by fs? */
- unsigned no_listxattr : 1;
+ unsigned no_listxattr:1;
/** Is removexattr not implemented by fs? */
- unsigned no_removexattr : 1;
+ 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;
+
+ /** Is bmap not implemented by fs? */
+ unsigned no_bmap:1;
+
+ /** Is poll not implemented by fs? */
+ unsigned no_poll:1;
+
+ /** Do multi-page cached writes */
+ unsigned big_writes:1;
+
+ /** Don't apply umask to creation modes */
+ unsigned dont_mask:1;
+
+ /** The number of requests waiting for completion */
+ atomic_t num_waiting;
+
+ /** Negotiated minor version */
+ unsigned minor;
/** Backing dev info */
struct backing_dev_info bdi;
-};
-struct fuse_getdir_out_i {
- int fd;
- void *file; /* Used by kernel only */
-};
+ /** Entry on the fuse_conn_list */
+ struct list_head entry;
-static inline struct fuse_conn **get_fuse_conn_super_p(struct super_block *sb)
-{
- return (struct fuse_conn **) &sb->s_fs_info;
-}
+ /** Device ID from super block */
+ dev_t dev;
+
+ /** 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];
+
+ /** Reserved request for the DESTROY message */
+ struct fuse_req *destroy_req;
+
+ /** Version counter for attribute changes */
+ u64 attr_version;
+
+ /** Called on final put */
+ void (*release)(struct fuse_conn *);
+
+ /** Super block for this connection. */
+ struct super_block *sb;
+
+ /** Read/write semaphore to hold when accessing sb. */
+ struct rw_semaphore killsb;
+};
static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
{
- return *get_fuse_conn_super_p(sb);
+ return sb->s_fs_info;
}
static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
}
/** Device operations */
-extern struct file_operations fuse_dev_operations;
+extern const struct file_operations fuse_dev_operations;
+
+extern const struct dentry_operations fuse_dentry_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
+ * Inode to nodeid comparison.
*/
-extern spinlock_t fuse_lock;
+int fuse_inode_eq(struct inode *inode, void *_nodeidp);
/**
* Get a filled in inode
*/
-struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
- int generation, struct fuse_attr *attr);
+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);
/**
* Send FORGET command
*/
void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
- unsigned long nodeid, u64 nlookup);
+ u64 nodeid, u64 nlookup);
/**
- * Initialise file operations on a regular file
+ * Initialize READ or READDIR request
+ */
+void fuse_read_fill(struct fuse_req *req, struct file *file,
+ loff_t pos, size_t count, int opcode);
+
+/**
+ * Send OPEN or OPENDIR request
+ */
+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);
+
+/**
+ * Send RELEASE or RELEASEDIR request
+ */
+void fuse_release_common(struct file *file, int opcode);
+
+/**
+ * Send FSYNC or FSYNCDIR request
+ */
+int fuse_fsync_common(struct file *file, struct dentry *de, int datasync,
+ int isdir);
+
+/**
+ * Notify poll wakeup
+ */
+int fuse_notify_poll_wakeup(struct fuse_conn *fc,
+ struct fuse_notify_poll_wakeup_out *outarg);
+
+/**
+ * Initialize file operations on a regular file
*/
void fuse_init_file_inode(struct inode *inode);
/**
- * Initialise inode operations on regular files and special files
+ * Initialize inode operations on regular files and special files
*/
void fuse_init_common(struct inode *inode);
/**
- * Initialise inode and file operations on a directory
+ * Initialize inode and file operations on a directory
*/
void fuse_init_dir(struct inode *inode);
/**
- * Initialise inode operations on a symlink
+ * Initialize inode operations on a symlink
*/
void fuse_init_symlink(struct inode *inode);
/**
* Change attributes of an inode
*/
-void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr);
+void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
+ u64 attr_valid, u64 attr_version);
-/**
- * Check if the connection can be released, and if yes, then free the
- * connection structure
- */
-void fuse_release_conn(struct fuse_conn *fc);
+void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
+ u64 attr_valid);
/**
* Initialize the client device
*/
void fuse_dev_cleanup(void);
+int fuse_ctl_init(void);
+void fuse_ctl_cleanup(void);
+
/**
* Allocate a request
*/
struct fuse_req *fuse_request_alloc(void);
+struct fuse_req *fuse_request_alloc_nofs(void);
+
/**
* Free 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);
/**
- * Reserve a preallocated request, only interruptible by SIGKILL
+ * Decrement reference count of a request. If count goes to zero free
+ * the request.
*/
-struct fuse_req *fuse_get_request_nonint(struct fuse_conn *fc);
+void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);
/**
- * Decrement reference count of a request. If count goes to zero put
- * on unused list (preallocated) or free reqest (not preallocated).
+ * Send a request (synchronous)
*/
-void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);
+void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req);
/**
- * Send a request (synchronous, interruptible)
+ * Send a request with no reply
*/
-void request_send(struct fuse_conn *fc, struct fuse_req *req);
+void fuse_request_send_noreply(struct fuse_conn *fc, struct fuse_req *req);
/**
- * Send a request (synchronous, non-interruptible except by SIGKILL)
+ * Send a request in the background
*/
-void request_send_nonint(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);
/**
- * Send a request with no reply
+ * Invalidate inode attributes
*/
-void request_send_noreply(struct fuse_conn *fc, struct fuse_req *req);
+void fuse_invalidate_attr(struct inode *inode);
+
+void fuse_invalidate_entry_cache(struct dentry *entry);
/**
- * Send a request in the background
+ * Acquire reference to fuse_conn
*/
-void request_send_background(struct fuse_conn *fc, struct fuse_req *req);
+struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
+
+void fuse_conn_kill(struct fuse_conn *fc);
/**
- * Release inodes and file assiciated with background request
+ * Initialize fuse_conn
*/
-void fuse_release_background(struct fuse_req *req);
+void fuse_conn_init(struct fuse_conn *fc);
/**
- * Get the attributes of a file
+ * Release reference to fuse_conn
*/
-int fuse_do_getattr(struct inode *inode);
+void fuse_conn_put(struct fuse_conn *fc);
/**
- * Invalidate inode attributes
+ * Add connection to control filesystem
*/
-void fuse_invalidate_attr(struct inode *inode);
+int fuse_ctl_add_conn(struct fuse_conn *fc);
+
+/**
+ * Remove connection from control filesystem
+ */
+void fuse_ctl_remove_conn(struct fuse_conn *fc);
+
+/**
+ * Is file type valid?
+ */
+int fuse_valid_type(int m);
+
+/**
+ * Is task allowed to perform filesystem operation?
+ */
+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);
+
+/**
+ * File-system tells the kernel to invalidate cache for the given node id.
+ */
+int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
+ loff_t offset, loff_t len);
/**
- * Send the INIT message
+ * File-system tells the kernel to invalidate parent attributes and
+ * the dentry matching parent/name.
*/
-void fuse_send_init(struct fuse_conn *fc);
+int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_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);
+unsigned fuse_file_poll(struct file *file, poll_table *wait);
+int fuse_dev_release(struct inode *inode, struct file *file);
+
+#endif /* _FS_FUSE_I_H */