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diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
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+/*
+ 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;
+};
+
+/* Submount lookup tracking */
+struct fuse_submount_lookup {
+ /** Refcount */
+ refcount_t count;
+
+ /** Unique ID, which identifies the inode between userspace
+ * and kernel */
+ u64 nodeid;
+
+ /** The request used for sending the FORGET message */
+ struct fuse_forget_link *forget;
+};
+
+/** 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;
+
+#ifdef CONFIG_FUSE_DAX
+ /*
+ * Dax specific inode data
+ */
+ struct fuse_inode_dax *dax;
+#endif
+ /** Submount specific lookup tracking */
+ struct fuse_submount_lookup *submount_lookup;
+};
+
+/** 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;
+};
+
+enum fuse_dax_mode {
+ FUSE_DAX_INODE_DEFAULT, /* default */
+ FUSE_DAX_ALWAYS, /* "-o dax=always" */
+ FUSE_DAX_NEVER, /* "-o dax=never" */
+ FUSE_DAX_INODE_USER, /* "-o dax=inode" */
+};
+
+static inline bool fuse_is_inode_dax_mode(enum fuse_dax_mode mode)
+{
+ return mode == FUSE_DAX_INODE_DEFAULT || mode == FUSE_DAX_INODE_USER;
+}
+
+struct fuse_fs_context {
+ int fd;
+ struct file *file;
+ 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;
+ enum fuse_dax_mode dax_mode;
+ 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;
+};
+
+struct fuse_sync_bucket {
+ /* count is a possible scalability bottleneck */
+ atomic_t count;
+ wait_queue_head_t waitq;
+ struct rcu_head rcu;
+};
+
+/**
+ * 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;
+
+ /** Maximum 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 readahead 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;
+
+ /*
+ * fs kills suid/sgid/cap on write/chown/trunc. suid is killed on
+ * write/trunc only if caller did not have CAP_FSETID. sgid is killed
+ * on write/truncate only if caller did not have CAP_FSETID as well as
+ * file has group execute permission.
+ */
+ unsigned handle_killpriv_v2:1;
+
+ /*
+ * 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;
+
+ /** Does file server support extended setxattr */
+ unsigned setxattr_ext: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 responsible 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;
+
+ /* Propagate syncfs() to server */
+ unsigned int sync_fs:1;
+
+ /* Initialize security xattrs when creating a new inode */
+ unsigned int init_security:1;
+
+ /* Does the filesystem support per inode DAX? */
+ unsigned int inode_dax:1;
+
+ /* Is tmpfile not implemented by fs? */
+ unsigned int no_tmpfile: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 mode */
+ enum fuse_dax_mode dax_mode;
+
+ /* 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;
+
+ /* New writepages go into this bucket */
+ struct fuse_sync_bucket __rcu *curr_bucket;
+};
+
+/*
+ * 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;
+
+ /*
+ * 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)
+{
+ return get_fuse_mount_super(sb)->fc;
+}
+
+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)
+{
+ return get_fuse_mount_super(inode->i_sb)->fc;
+}
+
+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));
+}
+
+static inline struct page **fuse_pages_alloc(unsigned int npages, gfp_t flags,
+ struct fuse_page_desc **desc)
+{
+ struct page **pages;
+
+ pages = kzalloc(npages * (sizeof(struct page *) +
+ sizeof(struct fuse_page_desc)), flags);
+ *desc = (void *) (pages + npages);
+
+ return pages;
+}
+
+static inline void fuse_page_descs_length_init(struct fuse_page_desc *descs,
+ unsigned int index,
+ unsigned int nr_pages)
+{
+ int i;
+
+ for (i = index; i < index + nr_pages; i++)
+ descs[i].length = PAGE_SIZE - descs[i].offset;
+}
+
+static inline void fuse_sync_bucket_dec(struct fuse_sync_bucket *bucket)
+{
+ /* Need RCU protection to prevent use after free after the decrement */
+ rcu_read_lock();
+ if (atomic_dec_and_test(&bucket->count))
+ wake_up(&bucket->waitq);
+ rcu_read_unlock();
+}
+
+/** 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,
+ unsigned 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, unsigned int flags);
+
+/**
+ * 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, u32 cache_mask);
+
+u32 fuse_get_cache_mask(struct inode *inode);
+
+/**
+ * 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
+ */
+
+/* Attributes possibly changed on data modification */
+#define FUSE_STATX_MODIFY (STATX_MTIME | STATX_CTIME | STATX_BLOCKS)
+
+/* Attributes possibly changed on data and/or size modification */
+#define FUSE_STATX_MODSIZE (FUSE_STATX_MODIFY | STATX_SIZE)
+
+void fuse_invalidate_attr(struct inode *inode);
+void fuse_invalidate_attr_mask(struct inode *inode, u32 mask);
+
+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);
+
+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);
+
+/*
+ * Remove the mount from the connection
+ *
+ * Returns whether this was the last mount
+ */
+bool fuse_mount_remove(struct fuse_mount *fm);
+
+/*
+ * Setup context ops for submounts
+ */
+int fuse_init_fs_context_submount(struct fs_context *fsc);
+
+/*
+ * Shut down the connection (possibly sending DESTROY request).
+ */
+void fuse_conn_destroy(struct fuse_mount *fm);
+
+/* Drop the connection and free the fuse mount */
+void fuse_mount_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, u32 mask);
+
+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_attr(struct inode *inode, loff_t pos, ssize_t written);
+
+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, unsigned int extra_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, bool rcu);
+int fuse_set_acl(struct user_namespace *mnt_userns, 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, enum fuse_dax_mode mode,
+ 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, unsigned int flags);
+void fuse_dax_inode_cleanup(struct inode *inode);
+void fuse_dax_dontcache(struct inode *inode, unsigned int flags);
+bool fuse_dax_check_alignment(struct fuse_conn *fc, unsigned int map_alignment);
+void fuse_dax_cancel_work(struct fuse_conn *fc);
+
+/* ioctl.c */
+long fuse_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg);
+int fuse_fileattr_get(struct dentry *dentry, struct fileattr *fa);
+int fuse_fileattr_set(struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct fileattr *fa);
+
+/* file.c */
+
+struct fuse_file *fuse_file_open(struct fuse_mount *fm, u64 nodeid,
+ unsigned int open_flags, bool isdir);
+void fuse_file_release(struct inode *inode, struct fuse_file *ff,
+ unsigned int open_flags, fl_owner_t id, bool isdir);
+
+#endif /* _FS_FUSE_I_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 09:40:43 +0000