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Diffstat (limited to 'fs/fuse/fuse_i.h')
| -rw-r--r-- | fs/fuse/fuse_i.h | 1239 |
1 files changed, 1239 insertions, 0 deletions
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h new file mode 100644 index 000000000..ceaa68683 --- /dev/null +++ b/fs/fuse/fuse_i.h @@ -0,0 +1,1239 @@ +/* + FUSE: Filesystem in Userspace + 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 + +#ifndef pr_fmt +# define pr_fmt(fmt) "fuse: " fmt +#endif + +#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> +#include <linux/kref.h> +#include <linux/xattr.h> +#include <linux/pid_namespace.h> +#include <linux/refcount.h> +#include <linux/user_namespace.h> + +/** Default max number of pages that can be used in a single read request */ +#define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32 + +/** Maximum of max_pages received in init_out */ +#define FUSE_MAX_MAX_PAGES 256 + +/** 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 + +/** 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; + +/** Module parameters */ +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; +}; + +/** FUSE inode */ +struct fuse_inode { + /** Inode data */ + struct inode inode; + + /** Unique ID, which identifies the inode between userspace + * and kernel */ + u64 nodeid; + + /** Number of lookups on this inode */ + u64 nlookup; + + /** The request used for sending the FORGET message */ + struct fuse_forget_link *forget; + + /** Time in jiffies until the file attributes are valid */ + u64 i_time; + + /* Which attributes are invalid */ + u32 inval_mask; + + /** The sticky bit in inode->i_mode may have been removed, so + preserve the original mode */ + umode_t orig_i_mode; + + /** 64 bit inode number */ + u64 orig_ino; + + /** Version of last attribute change */ + u64 attr_version; + + union { + /* Write related fields (regular file only) */ + struct { + /* Files usable in writepage. Protected by fi->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 rb_root writepages; + }; + + /* readdir cache (directory only) */ + struct { + /* true if fully cached */ + bool cached; + + /* size of cache */ + loff_t size; + + /* position at end of cache (position of next entry) */ + loff_t pos; + + /* version of the cache */ + u64 version; + + /* modification time of directory when cache was + * started */ + struct timespec64 mtime; + + /* iversion of directory when cache was started */ + u64 iversion; + + /* protects above fields */ + spinlock_t lock; + } rdc; + }; + + /** Miscellaneous bits describing inode state */ + unsigned long state; + + /** Lock for serializing lookup and readdir for back compatibility*/ + struct mutex mutex; + + /** Lock to protect write related fields */ + spinlock_t lock; + + /** + * Can't take inode lock in fault path (leads to circular dependency). + * Introduce another semaphore which can be taken in fault path and + * then other filesystem paths can take this to block faults. + */ + struct rw_semaphore i_mmap_sem; + +#ifdef CONFIG_FUSE_DAX + /* + * Dax specific inode data + */ + struct fuse_inode_dax *dax; +#endif +}; + +/** FUSE inode state bits */ +enum { + /** Advise readdirplus */ + FUSE_I_ADVISE_RDPLUS, + /** Initialized with readdirplus */ + FUSE_I_INIT_RDPLUS, + /** An operation changing file size is in progress */ + FUSE_I_SIZE_UNSTABLE, + /* Bad inode */ + FUSE_I_BAD, +}; + +struct fuse_conn; +struct fuse_mount; +struct fuse_release_args; + +/** FUSE specific file data */ +struct fuse_file { + /** Fuse connection for this file */ + struct fuse_mount *fm; + + /* Argument space reserved for release */ + struct fuse_release_args *release_args; + + /** Kernel file handle guaranteed to be unique */ + u64 kh; + + /** File handle used by userspace */ + u64 fh; + + /** Node id of this file */ + u64 nodeid; + + /** Refcount */ + refcount_t count; + + /** FOPEN_* flags returned by open */ + u32 open_flags; + + /** Entry on inode's write_files list */ + struct list_head write_entry; + + /* Readdir related */ + struct { + /* + * Protects below fields against (crazy) parallel readdir on + * same open file. Uncontended in the normal case. + */ + struct mutex lock; + + /* Dir stream position */ + loff_t pos; + + /* Offset in cache */ + loff_t cache_off; + + /* Version of cache we are reading */ + u64 version; + + } readdir; + + /** 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; + + /** Has flock been performed on this file? */ + bool flock:1; +}; + +/** One input argument of a request */ +struct fuse_in_arg { + unsigned size; + const void *value; +}; + +/** One output argument of a request */ +struct fuse_arg { + unsigned size; + void *value; +}; + +/** FUSE page descriptor */ +struct fuse_page_desc { + unsigned int length; + unsigned int offset; +}; + +struct fuse_args { + uint64_t nodeid; + uint32_t opcode; + unsigned short in_numargs; + unsigned short out_numargs; + bool force:1; + bool noreply:1; + bool nocreds:1; + bool in_pages:1; + bool out_pages:1; + bool user_pages:1; + bool out_argvar:1; + bool page_zeroing:1; + bool page_replace:1; + bool may_block:1; + struct fuse_in_arg in_args[3]; + struct fuse_arg out_args[2]; + void (*end)(struct fuse_mount *fm, struct fuse_args *args, int error); +}; + +struct fuse_args_pages { + struct fuse_args args; + struct page **pages; + struct fuse_page_desc *descs; + unsigned int num_pages; +}; + +#define FUSE_ARGS(args) struct fuse_args args = {} + +/** The request IO state (for asynchronous processing) */ +struct fuse_io_priv { + struct kref refcnt; + int async; + spinlock_t lock; + unsigned reqs; + ssize_t bytes; + size_t size; + __u64 offset; + bool write; + bool should_dirty; + int err; + struct kiocb *iocb; + struct completion *done; + bool blocking; +}; + +#define FUSE_IO_PRIV_SYNC(i) \ +{ \ + .refcnt = KREF_INIT(1), \ + .async = 0, \ + .iocb = i, \ +} + +/** + * Request flags + * + * FR_ISREPLY: set if the request has reply + * FR_FORCE: force sending of the request even if interrupted + * FR_BACKGROUND: request is sent in the background + * FR_WAITING: request is counted as "waiting" + * FR_ABORTED: the request was aborted + * FR_INTERRUPTED: the request has been interrupted + * FR_LOCKED: data is being copied to/from the request + * FR_PENDING: request is not yet in userspace + * FR_SENT: request is in userspace, waiting for an answer + * FR_FINISHED: request is finished + * FR_PRIVATE: request is on private list + * FR_ASYNC: request is asynchronous + */ +enum fuse_req_flag { + FR_ISREPLY, + FR_FORCE, + FR_BACKGROUND, + FR_WAITING, + FR_ABORTED, + FR_INTERRUPTED, + FR_LOCKED, + FR_PENDING, + FR_SENT, + FR_FINISHED, + FR_PRIVATE, + FR_ASYNC, +}; + +/** + * A request to the client + * + * .waitq.lock protects the following fields: + * - FR_ABORTED + * - FR_LOCKED (may also be modified under fc->lock, tested under both) + */ +struct fuse_req { + /** This can be on either pending processing or io lists in + fuse_conn */ + struct list_head list; + + /** Entry on the interrupts list */ + struct list_head intr_entry; + + /* Input/output arguments */ + struct fuse_args *args; + + /** refcount */ + refcount_t count; + + /* Request flags, updated with test/set/clear_bit() */ + unsigned long flags; + + /* The request input header */ + struct { + struct fuse_in_header h; + } in; + + /* The request output header */ + struct { + struct fuse_out_header h; + } out; + + /** Used to wake up the task waiting for completion of request*/ + wait_queue_head_t waitq; + +#if IS_ENABLED(CONFIG_VIRTIO_FS) + /** virtio-fs's physically contiguous buffer for in and out args */ + void *argbuf; +#endif + + /** fuse_mount this request belongs to */ + struct fuse_mount *fm; +}; + +struct fuse_iqueue; + +/** + * Input queue callbacks + * + * Input queue signalling is device-specific. For example, the /dev/fuse file + * uses fiq->waitq and fasync to wake processes that are waiting on queue + * readiness. These callbacks allow other device types to respond to input + * queue activity. + */ +struct fuse_iqueue_ops { + /** + * Signal that a forget has been queued + */ + void (*wake_forget_and_unlock)(struct fuse_iqueue *fiq) + __releases(fiq->lock); + + /** + * Signal that an INTERRUPT request has been queued + */ + void (*wake_interrupt_and_unlock)(struct fuse_iqueue *fiq) + __releases(fiq->lock); + + /** + * Signal that a request has been queued + */ + void (*wake_pending_and_unlock)(struct fuse_iqueue *fiq) + __releases(fiq->lock); + + /** + * Clean up when fuse_iqueue is destroyed + */ + void (*release)(struct fuse_iqueue *fiq); +}; + +/** /dev/fuse input queue operations */ +extern const struct fuse_iqueue_ops fuse_dev_fiq_ops; + +struct fuse_iqueue { + /** Connection established */ + unsigned connected; + + /** Lock protecting accesses to members of this structure */ + spinlock_t lock; + + /** Readers of the connection are waiting on this */ + wait_queue_head_t waitq; + + /** The next unique request id */ + u64 reqctr; + + /** The list of pending requests */ + struct list_head pending; + + /** Pending interrupts */ + struct list_head interrupts; + + /** Queue of pending forgets */ + struct fuse_forget_link forget_list_head; + struct fuse_forget_link *forget_list_tail; + + /** Batching of FORGET requests (positive indicates FORGET batch) */ + int forget_batch; + + /** O_ASYNC requests */ + struct fasync_struct *fasync; + + /** Device-specific callbacks */ + const struct fuse_iqueue_ops *ops; + + /** Device-specific state */ + void *priv; +}; + +#define FUSE_PQ_HASH_BITS 8 +#define FUSE_PQ_HASH_SIZE (1 << FUSE_PQ_HASH_BITS) + +struct fuse_pqueue { + /** Connection established */ + unsigned connected; + + /** Lock protecting accessess to members of this structure */ + spinlock_t lock; + + /** Hash table of requests being processed */ + struct list_head *processing; + + /** The list of requests under I/O */ + struct list_head io; +}; + +/** + * Fuse device instance + */ +struct fuse_dev { + /** Fuse connection for this device */ + struct fuse_conn *fc; + + /** Processing queue */ + struct fuse_pqueue pq; + + /** list entry on fc->devices */ + struct list_head entry; +}; + +struct fuse_fs_context { + int fd; + unsigned int rootmode; + kuid_t user_id; + kgid_t group_id; + bool is_bdev:1; + bool fd_present:1; + bool rootmode_present:1; + bool user_id_present:1; + bool group_id_present:1; + bool default_permissions:1; + bool allow_other:1; + bool destroy:1; + bool no_control:1; + bool no_force_umount:1; + bool legacy_opts_show:1; + bool dax:1; + unsigned int max_read; + unsigned int blksize; + const char *subtype; + + /* DAX device, may be NULL */ + struct dax_device *dax_dev; + + /* fuse_dev pointer to fill in, should contain NULL on entry */ + void **fudptr; +}; + +/** + * A Fuse connection. + * + * This structure is created, when the root filesystem is mounted, and + * is destroyed, when the client device is closed and the last + * fuse_mount is destroyed. + */ +struct fuse_conn { + /** Lock protecting accessess to members of this structure */ + spinlock_t lock; + + /** Refcount */ + refcount_t count; + + /** Number of fuse_dev's */ + atomic_t dev_count; + + struct rcu_head rcu; + + /** The user id for this mount */ + kuid_t user_id; + + /** The group id for this mount */ + kgid_t group_id; + + /** The pid namespace for this mount */ + struct pid_namespace *pid_ns; + + /** The user namespace for this mount */ + struct user_namespace *user_ns; + + /** Maximum read size */ + unsigned max_read; + + /** Maximum write size */ + unsigned max_write; + + /** Maxmum number of pages that can be used in a single request */ + unsigned int max_pages; + + /** Constrain ->max_pages to this value during feature negotiation */ + unsigned int max_pages_limit; + + /** Input queue */ + struct fuse_iqueue iq; + + /** The next unique kernel file handle */ + atomic64_t 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; + + /** Number of requests currently in the background */ + unsigned num_background; + + /** Number of background requests currently queued for userspace */ + unsigned active_background; + + /** The list of background requests set aside for later queuing */ + struct list_head bg_queue; + + /** Protects: max_background, congestion_threshold, num_background, + * active_background, bg_queue, blocked */ + spinlock_t bg_lock; + + /** Flag indicating that INIT reply has been received. Allocating + * any fuse request will be suspended until the flag is set */ + int initialized; + + /** 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; + + /** Connection established, cleared on umount, connection + abort and device release */ + unsigned connected; + + /** Connection aborted via sysfs */ + bool aborted; + + /** 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; + + /** Return an unique read error after abort. Only set in INIT */ + unsigned abort_err: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; + + /** write-back cache policy (default is write-through) */ + unsigned writeback_cache:1; + + /** allow parallel lookups and readdir (default is serialized) */ + unsigned parallel_dirops:1; + + /** handle fs handles killing suid/sgid/cap on write/chown/trunc */ + unsigned handle_killpriv:1; + + /** cache READLINK responses in page cache */ + unsigned cache_symlinks:1; + + /* show legacy mount options */ + unsigned int legacy_opts_show:1; + + /* + * The following bitfields are only for optimization purposes + * and hence races in setting them will not cause malfunction + */ + + /** Is open/release not implemented by fs? */ + unsigned no_open:1; + + /** Is opendir/releasedir not implemented by fs? */ + unsigned no_opendir:1; + + /** Is fsync not implemented by fs? */ + unsigned no_fsync:1; + + /** Is fsyncdir not implemented by fs? */ + unsigned no_fsyncdir:1; + + /** Is flush not implemented by fs? */ + unsigned no_flush:1; + + /** Is setxattr not implemented by fs? */ + unsigned no_setxattr:1; + + /** Is getxattr not implemented by fs? */ + unsigned no_getxattr:1; + + /** Is listxattr not implemented by fs? */ + unsigned no_listxattr:1; + + /** Is removexattr not implemented by fs? */ + unsigned no_removexattr:1; + + /** Are posix 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; + + /** Are BSD file locking primitives not implemented by fs? */ + unsigned no_flock:1; + + /** Is fallocate not implemented by fs? */ + unsigned no_fallocate:1; + + /** Is rename with flags implemented by fs? */ + unsigned no_rename2:1; + + /** Use enhanced/automatic page cache invalidation. */ + unsigned auto_inval_data:1; + + /** Filesystem is fully reponsible for page cache invalidation. */ + unsigned explicit_inval_data:1; + + /** Does the filesystem support readdirplus? */ + unsigned do_readdirplus:1; + + /** Does the filesystem want adaptive readdirplus? */ + unsigned readdirplus_auto:1; + + /** Does the filesystem support asynchronous direct-IO submission? */ + unsigned async_dio:1; + + /** Is lseek not implemented by fs? */ + unsigned no_lseek:1; + + /** Does the filesystem support posix acls? */ + unsigned posix_acl:1; + + /** Check permissions based on the file mode or not? */ + unsigned default_permissions:1; + + /** Allow other than the mounter user to access the filesystem ? */ + unsigned allow_other:1; + + /** Does the filesystem support copy_file_range? */ + unsigned no_copy_file_range:1; + + /* Send DESTROY request */ + unsigned int destroy:1; + + /* Delete dentries that have gone stale */ + unsigned int delete_stale:1; + + /** Do not create entry in fusectl fs */ + unsigned int no_control:1; + + /** Do not allow MNT_FORCE umount */ + unsigned int no_force_umount:1; + + /* Auto-mount submounts announced by the server */ + unsigned int auto_submounts:1; + + /** The number of requests waiting for completion */ + atomic_t num_waiting; + + /** Negotiated minor version */ + unsigned minor; + + /** Entry on the fuse_mount_list */ + struct list_head entry; + + /** Device ID from the root 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; + + /** Key for lock owner ID scrambling */ + u32 scramble_key[4]; + + /** Version counter for attribute changes */ + atomic64_t attr_version; + + /** Called on final put */ + void (*release)(struct fuse_conn *); + + /** + * Read/write semaphore to hold when accessing the sb of any + * fuse_mount belonging to this connection + */ + struct rw_semaphore killsb; + + /** List of device instances belonging to this connection */ + struct list_head devices; + +#ifdef CONFIG_FUSE_DAX + /* Dax specific conn data, non-NULL if DAX is enabled */ + struct fuse_conn_dax *dax; +#endif + + /** List of filesystems using this connection */ + struct list_head mounts; +}; + +/* + * Represents a mounted filesystem, potentially a submount. + * + * This object allows sharing a fuse_conn between separate mounts to + * allow submounts with dedicated superblocks and thus separate device + * IDs. + */ +struct fuse_mount { + /* Underlying (potentially shared) connection to the FUSE server */ + struct fuse_conn *fc; + + /* Refcount */ + refcount_t count; + + /* + * Super block for this connection (fc->killsb must be held when + * accessing this). + */ + struct super_block *sb; + + /* Entry on fc->mounts */ + struct list_head fc_entry; +}; + +static inline struct fuse_mount *get_fuse_mount_super(struct super_block *sb) +{ + return sb->s_fs_info; +} + +static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb) +{ + struct fuse_mount *fm = get_fuse_mount_super(sb); + + return fm ? fm->fc : NULL; +} + +static inline struct fuse_mount *get_fuse_mount(struct inode *inode) +{ + return get_fuse_mount_super(inode->i_sb); +} + +static inline struct fuse_conn *get_fuse_conn(struct inode *inode) +{ + struct fuse_mount *fm = get_fuse_mount(inode); + + return fm ? fm->fc : NULL; +} + +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; +} + +static inline int invalid_nodeid(u64 nodeid) +{ + return !nodeid || nodeid == FUSE_ROOT_ID; +} + +static inline u64 fuse_get_attr_version(struct fuse_conn *fc) +{ + return atomic64_read(&fc->attr_version); +} + +static inline bool fuse_stale_inode(const struct inode *inode, int generation, + struct fuse_attr *attr) +{ + return inode->i_generation != generation || + inode_wrong_type(inode, attr->mode); +} + +static inline void fuse_make_bad(struct inode *inode) +{ + remove_inode_hash(inode); + set_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state); +} + +static inline bool fuse_is_bad(struct inode *inode) +{ + return unlikely(test_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state)); +} + +/** Device operations */ +extern const struct file_operations fuse_dev_operations; + +extern const struct dentry_operations fuse_dentry_operations; +extern const struct dentry_operations fuse_root_dentry_operations; + +/** + * Get a filled in inode + */ +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, const struct qstr *name, + struct fuse_entry_out *outarg, struct inode **inode); + +/** + * Send FORGET command + */ +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); + +struct fuse_forget_link *fuse_dequeue_forget(struct fuse_iqueue *fiq, + unsigned int max, + unsigned int *countp); + +/* + * Initialize READ or READDIR request + */ +struct fuse_io_args { + union { + struct { + struct fuse_read_in in; + u64 attr_ver; + } read; + struct { + struct fuse_write_in in; + struct fuse_write_out out; + bool page_locked; + } write; + }; + struct fuse_args_pages ap; + struct fuse_io_priv *io; + struct fuse_file *ff; +}; + +void fuse_read_args_fill(struct fuse_io_args *ia, 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_mount *fm); +void fuse_file_free(struct fuse_file *ff); +void fuse_finish_open(struct inode *inode, struct file *file); + +void fuse_sync_release(struct fuse_inode *fi, struct fuse_file *ff, int flags); + +/** + * Send RELEASE or RELEASEDIR request + */ +void fuse_release_common(struct file *file, bool isdir); + +/** + * Send FSYNC or FSYNCDIR request + */ +int fuse_fsync_common(struct file *file, loff_t start, loff_t end, + int datasync, int opcode); + +/** + * 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); + +/** + * Initialize inode operations on regular files and special files + */ +void fuse_init_common(struct inode *inode); + +/** + * Initialize inode and file operations on a directory + */ +void fuse_init_dir(struct inode *inode); + +/** + * 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, + u64 attr_valid, u64 attr_version); + +void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr, + u64 attr_valid); + +/** + * Initialize the client device + */ +int fuse_dev_init(void); + +/** + * Cleanup the client device + */ +void fuse_dev_cleanup(void); + +int fuse_ctl_init(void); +void __exit fuse_ctl_cleanup(void); + +/** + * Simple request sending that does request allocation and freeing + */ +ssize_t fuse_simple_request(struct fuse_mount *fm, struct fuse_args *args); +int fuse_simple_background(struct fuse_mount *fm, struct fuse_args *args, + gfp_t gfp_flags); + +/** + * End a finished request + */ +void fuse_request_end(struct fuse_req *req); + +/* Abort all requests */ +void fuse_abort_conn(struct fuse_conn *fc); +void fuse_wait_aborted(struct fuse_conn *fc); + +/** + * Invalidate inode attributes + */ +void fuse_invalidate_attr(struct inode *inode); + +void fuse_invalidate_entry_cache(struct dentry *entry); + +void fuse_invalidate_atime(struct inode *inode); + +u64 entry_attr_timeout(struct fuse_entry_out *o); +void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o); + +/** + * Acquire reference to fuse_conn + */ +struct fuse_conn *fuse_conn_get(struct fuse_conn *fc); + +/** + * Initialize fuse_conn + */ +void fuse_conn_init(struct fuse_conn *fc, struct fuse_mount *fm, + struct user_namespace *user_ns, + const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv); + +/** + * Release reference to fuse_conn + */ +void fuse_conn_put(struct fuse_conn *fc); + +/** + * Acquire reference to fuse_mount + */ +struct fuse_mount *fuse_mount_get(struct fuse_mount *fm); + +/** + * Release reference to fuse_mount + */ +void fuse_mount_put(struct fuse_mount *fm); + +struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc); +struct fuse_dev *fuse_dev_alloc(void); +void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc); +void fuse_dev_free(struct fuse_dev *fud); +void fuse_send_init(struct fuse_mount *fm); + +/** + * Fill in superblock and initialize fuse connection + * @sb: partially-initialized superblock to fill in + * @ctx: mount context + */ +int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx); + +/* + * Fill in superblock for submounts + * @sb: partially-initialized superblock to fill in + * @parent_fi: The fuse_inode of the parent filesystem where this submount is + * mounted + */ +int fuse_fill_super_submount(struct super_block *sb, + struct fuse_inode *parent_fi); + +/* + * Remove the mount from the connection + * + * Returns whether this was the last mount + */ +bool fuse_mount_remove(struct fuse_mount *fm); + +/* + * Shut down the connection (possibly sending DESTROY request). + */ +void fuse_conn_destroy(struct fuse_mount *fm); + +/** + * 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); + +/** + * Is file type valid? + */ +int fuse_valid_type(int m); + +bool fuse_invalid_attr(struct fuse_attr *attr); + +/** + * Is current process allowed to perform filesystem operation? + */ +int fuse_allow_current_process(struct fuse_conn *fc); + +u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id); + +void fuse_flush_time_update(struct inode *inode); +void fuse_update_ctime(struct inode *inode); + +int fuse_update_attributes(struct inode *inode, struct file *file); + +void fuse_flush_writepages(struct inode *inode); + +void fuse_set_nowrite(struct inode *inode); +void fuse_release_nowrite(struct inode *inode); + +/** + * Scan all fuse_mounts belonging to fc to find the first where + * ilookup5() returns a result. Return that result and the + * respective fuse_mount in *fm (unless fm is NULL). + * + * The caller must hold fc->killsb. + */ +struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid, + struct fuse_mount **fm); + +/** + * File-system tells the kernel to invalidate cache for the given node id. + */ +int fuse_reverse_inval_inode(struct fuse_conn *fc, u64 nodeid, + loff_t offset, loff_t len); + +/** + * File-system tells the kernel to invalidate parent attributes and + * the dentry matching parent/name. + * + * If the child_nodeid is non-zero and: + * - matches the inode number for the dentry matching parent/name, + * - is not a mount point + * - is a file or oan empty directory + * then the dentry is unhashed (d_delete()). + */ +int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid, + u64 child_nodeid, struct qstr *name); + +int fuse_do_open(struct fuse_mount *fm, u64 nodeid, struct file *file, + bool isdir); + +/** + * fuse_direct_io() flags + */ + +/** If set, it is WRITE; otherwise - READ */ +#define FUSE_DIO_WRITE (1 << 0) + +/** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */ +#define FUSE_DIO_CUSE (1 << 1) + +ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter, + loff_t *ppos, int flags); +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); +__poll_t fuse_file_poll(struct file *file, poll_table *wait); +int fuse_dev_release(struct inode *inode, struct file *file); + +bool fuse_write_update_size(struct inode *inode, loff_t pos); + +int fuse_flush_times(struct inode *inode, struct fuse_file *ff); +int fuse_write_inode(struct inode *inode, struct writeback_control *wbc); + +int fuse_do_setattr(struct dentry *dentry, struct iattr *attr, + struct file *file); + +void fuse_set_initialized(struct fuse_conn *fc); + +void fuse_unlock_inode(struct inode *inode, bool locked); +bool fuse_lock_inode(struct inode *inode); + +int fuse_setxattr(struct inode *inode, const char *name, const void *value, + size_t size, int flags); +ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value, + size_t size); +ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size); +int fuse_removexattr(struct inode *inode, const char *name); +extern const struct xattr_handler *fuse_xattr_handlers[]; +extern const struct xattr_handler *fuse_acl_xattr_handlers[]; +extern const struct xattr_handler *fuse_no_acl_xattr_handlers[]; + +struct posix_acl; +struct posix_acl *fuse_get_acl(struct inode *inode, int type); +int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type); + + +/* readdir.c */ +int fuse_readdir(struct file *file, struct dir_context *ctx); + +/** + * Return the number of bytes in an arguments list + */ +unsigned int fuse_len_args(unsigned int numargs, struct fuse_arg *args); + +/** + * Get the next unique ID for a request + */ +u64 fuse_get_unique(struct fuse_iqueue *fiq); +void fuse_free_conn(struct fuse_conn *fc); + +/* dax.c */ + +#define FUSE_IS_DAX(inode) (IS_ENABLED(CONFIG_FUSE_DAX) && IS_DAX(inode)) + +ssize_t fuse_dax_read_iter(struct kiocb *iocb, struct iov_iter *to); +ssize_t fuse_dax_write_iter(struct kiocb *iocb, struct iov_iter *from); +int fuse_dax_mmap(struct file *file, struct vm_area_struct *vma); +int fuse_dax_break_layouts(struct inode *inode, u64 dmap_start, u64 dmap_end); +int fuse_dax_conn_alloc(struct fuse_conn *fc, struct dax_device *dax_dev); +void fuse_dax_conn_free(struct fuse_conn *fc); +bool fuse_dax_inode_alloc(struct super_block *sb, struct fuse_inode *fi); +void fuse_dax_inode_init(struct inode *inode); +void fuse_dax_inode_cleanup(struct inode *inode); +bool fuse_dax_check_alignment(struct fuse_conn *fc, unsigned int map_alignment); +void fuse_dax_cancel_work(struct fuse_conn *fc); + +#endif /* _FS_FUSE_I_H */ |