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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /fs/fuse/inode.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/fuse/inode.c')
-rw-r--r--fs/fuse/inode.c2094
1 files changed, 2094 insertions, 0 deletions
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
new file mode 100644
index 0000000000..5974381356
--- /dev/null
+++ b/fs/fuse/inode.c
@@ -0,0 +1,2094 @@
+/*
+ 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.
+*/
+
+#include "fuse_i.h"
+
+#include <linux/pagemap.h>
+#include <linux/slab.h>
+#include <linux/file.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
+#include <linux/statfs.h>
+#include <linux/random.h>
+#include <linux/sched.h>
+#include <linux/exportfs.h>
+#include <linux/posix_acl.h>
+#include <linux/pid_namespace.h>
+#include <uapi/linux/magic.h>
+
+MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
+MODULE_DESCRIPTION("Filesystem in Userspace");
+MODULE_LICENSE("GPL");
+
+static struct kmem_cache *fuse_inode_cachep;
+struct list_head fuse_conn_list;
+DEFINE_MUTEX(fuse_mutex);
+
+static int set_global_limit(const char *val, const struct kernel_param *kp);
+
+unsigned max_user_bgreq;
+module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
+ &max_user_bgreq, 0644);
+__MODULE_PARM_TYPE(max_user_bgreq, "uint");
+MODULE_PARM_DESC(max_user_bgreq,
+ "Global limit for the maximum number of backgrounded requests an "
+ "unprivileged user can set");
+
+unsigned max_user_congthresh;
+module_param_call(max_user_congthresh, set_global_limit, param_get_uint,
+ &max_user_congthresh, 0644);
+__MODULE_PARM_TYPE(max_user_congthresh, "uint");
+MODULE_PARM_DESC(max_user_congthresh,
+ "Global limit for the maximum congestion threshold an "
+ "unprivileged user can set");
+
+#define FUSE_DEFAULT_BLKSIZE 512
+
+/** Maximum number of outstanding background requests */
+#define FUSE_DEFAULT_MAX_BACKGROUND 12
+
+/** Congestion starts at 75% of maximum */
+#define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4)
+
+#ifdef CONFIG_BLOCK
+static struct file_system_type fuseblk_fs_type;
+#endif
+
+struct fuse_forget_link *fuse_alloc_forget(void)
+{
+ return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL_ACCOUNT);
+}
+
+static struct fuse_submount_lookup *fuse_alloc_submount_lookup(void)
+{
+ struct fuse_submount_lookup *sl;
+
+ sl = kzalloc(sizeof(struct fuse_submount_lookup), GFP_KERNEL_ACCOUNT);
+ if (!sl)
+ return NULL;
+ sl->forget = fuse_alloc_forget();
+ if (!sl->forget)
+ goto out_free;
+
+ return sl;
+
+out_free:
+ kfree(sl);
+ return NULL;
+}
+
+static struct inode *fuse_alloc_inode(struct super_block *sb)
+{
+ struct fuse_inode *fi;
+
+ fi = alloc_inode_sb(sb, fuse_inode_cachep, GFP_KERNEL);
+ if (!fi)
+ return NULL;
+
+ fi->i_time = 0;
+ fi->inval_mask = ~0;
+ fi->nodeid = 0;
+ fi->nlookup = 0;
+ fi->attr_version = 0;
+ fi->orig_ino = 0;
+ fi->state = 0;
+ fi->submount_lookup = NULL;
+ mutex_init(&fi->mutex);
+ spin_lock_init(&fi->lock);
+ fi->forget = fuse_alloc_forget();
+ if (!fi->forget)
+ goto out_free;
+
+ if (IS_ENABLED(CONFIG_FUSE_DAX) && !fuse_dax_inode_alloc(sb, fi))
+ goto out_free_forget;
+
+ return &fi->inode;
+
+out_free_forget:
+ kfree(fi->forget);
+out_free:
+ kmem_cache_free(fuse_inode_cachep, fi);
+ return NULL;
+}
+
+static void fuse_free_inode(struct inode *inode)
+{
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ mutex_destroy(&fi->mutex);
+ kfree(fi->forget);
+#ifdef CONFIG_FUSE_DAX
+ kfree(fi->dax);
+#endif
+ kmem_cache_free(fuse_inode_cachep, fi);
+}
+
+static void fuse_cleanup_submount_lookup(struct fuse_conn *fc,
+ struct fuse_submount_lookup *sl)
+{
+ if (!refcount_dec_and_test(&sl->count))
+ return;
+
+ fuse_queue_forget(fc, sl->forget, sl->nodeid, 1);
+ sl->forget = NULL;
+ kfree(sl);
+}
+
+static void fuse_evict_inode(struct inode *inode)
+{
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ /* Will write inode on close/munmap and in all other dirtiers */
+ WARN_ON(inode->i_state & I_DIRTY_INODE);
+
+ truncate_inode_pages_final(&inode->i_data);
+ clear_inode(inode);
+ if (inode->i_sb->s_flags & SB_ACTIVE) {
+ struct fuse_conn *fc = get_fuse_conn(inode);
+
+ if (FUSE_IS_DAX(inode))
+ fuse_dax_inode_cleanup(inode);
+ if (fi->nlookup) {
+ fuse_queue_forget(fc, fi->forget, fi->nodeid,
+ fi->nlookup);
+ fi->forget = NULL;
+ }
+
+ if (fi->submount_lookup) {
+ fuse_cleanup_submount_lookup(fc, fi->submount_lookup);
+ fi->submount_lookup = NULL;
+ }
+ }
+ if (S_ISREG(inode->i_mode) && !fuse_is_bad(inode)) {
+ WARN_ON(!list_empty(&fi->write_files));
+ WARN_ON(!list_empty(&fi->queued_writes));
+ }
+}
+
+static int fuse_reconfigure(struct fs_context *fsc)
+{
+ struct super_block *sb = fsc->root->d_sb;
+
+ sync_filesystem(sb);
+ if (fsc->sb_flags & SB_MANDLOCK)
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
+ * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
+ * so that it will fit.
+ */
+static ino_t fuse_squash_ino(u64 ino64)
+{
+ ino_t ino = (ino_t) ino64;
+ if (sizeof(ino_t) < sizeof(u64))
+ ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8;
+ return ino;
+}
+
+void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
+ struct fuse_statx *sx,
+ u64 attr_valid, u32 cache_mask)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ lockdep_assert_held(&fi->lock);
+
+ fi->attr_version = atomic64_inc_return(&fc->attr_version);
+ fi->i_time = attr_valid;
+ /* Clear basic stats from invalid mask */
+ set_mask_bits(&fi->inval_mask, STATX_BASIC_STATS, 0);
+
+ inode->i_ino = fuse_squash_ino(attr->ino);
+ inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
+ set_nlink(inode, attr->nlink);
+ inode->i_uid = make_kuid(fc->user_ns, attr->uid);
+ inode->i_gid = make_kgid(fc->user_ns, attr->gid);
+ inode->i_blocks = attr->blocks;
+
+ /* Sanitize nsecs */
+ attr->atimensec = min_t(u32, attr->atimensec, NSEC_PER_SEC - 1);
+ attr->mtimensec = min_t(u32, attr->mtimensec, NSEC_PER_SEC - 1);
+ attr->ctimensec = min_t(u32, attr->ctimensec, NSEC_PER_SEC - 1);
+
+ inode->i_atime.tv_sec = attr->atime;
+ inode->i_atime.tv_nsec = attr->atimensec;
+ /* mtime from server may be stale due to local buffered write */
+ if (!(cache_mask & STATX_MTIME)) {
+ inode->i_mtime.tv_sec = attr->mtime;
+ inode->i_mtime.tv_nsec = attr->mtimensec;
+ }
+ if (!(cache_mask & STATX_CTIME)) {
+ inode_set_ctime(inode, attr->ctime, attr->ctimensec);
+ }
+ if (sx) {
+ /* Sanitize nsecs */
+ sx->btime.tv_nsec =
+ min_t(u32, sx->btime.tv_nsec, NSEC_PER_SEC - 1);
+
+ /*
+ * Btime has been queried, cache is valid (whether or not btime
+ * is available or not) so clear STATX_BTIME from inval_mask.
+ *
+ * Availability of the btime attribute is indicated in
+ * FUSE_I_BTIME
+ */
+ set_mask_bits(&fi->inval_mask, STATX_BTIME, 0);
+ if (sx->mask & STATX_BTIME) {
+ set_bit(FUSE_I_BTIME, &fi->state);
+ fi->i_btime.tv_sec = sx->btime.tv_sec;
+ fi->i_btime.tv_nsec = sx->btime.tv_nsec;
+ }
+ }
+
+ if (attr->blksize != 0)
+ inode->i_blkbits = ilog2(attr->blksize);
+ else
+ inode->i_blkbits = inode->i_sb->s_blocksize_bits;
+
+ /*
+ * Don't set the sticky bit in i_mode, unless we want the VFS
+ * to check permissions. This prevents failures due to the
+ * check in may_delete().
+ */
+ fi->orig_i_mode = inode->i_mode;
+ if (!fc->default_permissions)
+ inode->i_mode &= ~S_ISVTX;
+
+ fi->orig_ino = attr->ino;
+
+ /*
+ * We are refreshing inode data and it is possible that another
+ * client set suid/sgid or security.capability xattr. So clear
+ * S_NOSEC. Ideally, we could have cleared it only if suid/sgid
+ * was set or if security.capability xattr was set. But we don't
+ * know if security.capability has been set or not. So clear it
+ * anyway. Its less efficient but should be safe.
+ */
+ inode->i_flags &= ~S_NOSEC;
+}
+
+u32 fuse_get_cache_mask(struct inode *inode)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+
+ if (!fc->writeback_cache || !S_ISREG(inode->i_mode))
+ return 0;
+
+ return STATX_MTIME | STATX_CTIME | STATX_SIZE;
+}
+
+void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
+ struct fuse_statx *sx,
+ u64 attr_valid, u64 attr_version)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ u32 cache_mask;
+ loff_t oldsize;
+ struct timespec64 old_mtime;
+
+ spin_lock(&fi->lock);
+ /*
+ * In case of writeback_cache enabled, writes update mtime, ctime and
+ * may update i_size. In these cases trust the cached value in the
+ * inode.
+ */
+ cache_mask = fuse_get_cache_mask(inode);
+ if (cache_mask & STATX_SIZE)
+ attr->size = i_size_read(inode);
+
+ if (cache_mask & STATX_MTIME) {
+ attr->mtime = inode->i_mtime.tv_sec;
+ attr->mtimensec = inode->i_mtime.tv_nsec;
+ }
+ if (cache_mask & STATX_CTIME) {
+ attr->ctime = inode_get_ctime(inode).tv_sec;
+ attr->ctimensec = inode_get_ctime(inode).tv_nsec;
+ }
+
+ if ((attr_version != 0 && fi->attr_version > attr_version) ||
+ test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) {
+ spin_unlock(&fi->lock);
+ return;
+ }
+
+ old_mtime = inode->i_mtime;
+ fuse_change_attributes_common(inode, attr, sx, attr_valid, cache_mask);
+
+ oldsize = inode->i_size;
+ /*
+ * In case of writeback_cache enabled, the cached writes beyond EOF
+ * extend local i_size without keeping userspace server in sync. So,
+ * attr->size coming from server can be stale. We cannot trust it.
+ */
+ if (!(cache_mask & STATX_SIZE))
+ i_size_write(inode, attr->size);
+ spin_unlock(&fi->lock);
+
+ if (!cache_mask && S_ISREG(inode->i_mode)) {
+ bool inval = false;
+
+ if (oldsize != attr->size) {
+ truncate_pagecache(inode, attr->size);
+ if (!fc->explicit_inval_data)
+ inval = true;
+ } else if (fc->auto_inval_data) {
+ struct timespec64 new_mtime = {
+ .tv_sec = attr->mtime,
+ .tv_nsec = attr->mtimensec,
+ };
+
+ /*
+ * Auto inval mode also checks and invalidates if mtime
+ * has changed.
+ */
+ if (!timespec64_equal(&old_mtime, &new_mtime))
+ inval = true;
+ }
+
+ if (inval)
+ invalidate_inode_pages2(inode->i_mapping);
+ }
+
+ if (IS_ENABLED(CONFIG_FUSE_DAX))
+ fuse_dax_dontcache(inode, attr->flags);
+}
+
+static void fuse_init_submount_lookup(struct fuse_submount_lookup *sl,
+ u64 nodeid)
+{
+ sl->nodeid = nodeid;
+ refcount_set(&sl->count, 1);
+}
+
+static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr,
+ struct fuse_conn *fc)
+{
+ inode->i_mode = attr->mode & S_IFMT;
+ inode->i_size = attr->size;
+ inode->i_mtime.tv_sec = attr->mtime;
+ inode->i_mtime.tv_nsec = attr->mtimensec;
+ inode_set_ctime(inode, attr->ctime, attr->ctimensec);
+ if (S_ISREG(inode->i_mode)) {
+ fuse_init_common(inode);
+ fuse_init_file_inode(inode, attr->flags);
+ } else if (S_ISDIR(inode->i_mode))
+ fuse_init_dir(inode);
+ else if (S_ISLNK(inode->i_mode))
+ fuse_init_symlink(inode);
+ else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
+ S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
+ fuse_init_common(inode);
+ init_special_inode(inode, inode->i_mode,
+ new_decode_dev(attr->rdev));
+ } else
+ BUG();
+ /*
+ * Ensure that we don't cache acls for daemons without FUSE_POSIX_ACL
+ * so they see the exact same behavior as before.
+ */
+ if (!fc->posix_acl)
+ inode->i_acl = inode->i_default_acl = ACL_DONT_CACHE;
+}
+
+static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
+{
+ u64 nodeid = *(u64 *) _nodeidp;
+ if (get_node_id(inode) == nodeid)
+ return 1;
+ else
+ return 0;
+}
+
+static int fuse_inode_set(struct inode *inode, void *_nodeidp)
+{
+ u64 nodeid = *(u64 *) _nodeidp;
+ get_fuse_inode(inode)->nodeid = nodeid;
+ return 0;
+}
+
+struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
+ int generation, struct fuse_attr *attr,
+ u64 attr_valid, u64 attr_version)
+{
+ struct inode *inode;
+ struct fuse_inode *fi;
+ struct fuse_conn *fc = get_fuse_conn_super(sb);
+
+ /*
+ * Auto mount points get their node id from the submount root, which is
+ * not a unique identifier within this filesystem.
+ *
+ * To avoid conflicts, do not place submount points into the inode hash
+ * table.
+ */
+ if (fc->auto_submounts && (attr->flags & FUSE_ATTR_SUBMOUNT) &&
+ S_ISDIR(attr->mode)) {
+ struct fuse_inode *fi;
+
+ inode = new_inode(sb);
+ if (!inode)
+ return NULL;
+
+ fuse_init_inode(inode, attr, fc);
+ fi = get_fuse_inode(inode);
+ fi->nodeid = nodeid;
+ fi->submount_lookup = fuse_alloc_submount_lookup();
+ if (!fi->submount_lookup) {
+ iput(inode);
+ return NULL;
+ }
+ /* Sets nlookup = 1 on fi->submount_lookup->nlookup */
+ fuse_init_submount_lookup(fi->submount_lookup, nodeid);
+ inode->i_flags |= S_AUTOMOUNT;
+ goto done;
+ }
+
+retry:
+ inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
+ if (!inode)
+ return NULL;
+
+ if ((inode->i_state & I_NEW)) {
+ inode->i_flags |= S_NOATIME;
+ if (!fc->writeback_cache || !S_ISREG(attr->mode))
+ inode->i_flags |= S_NOCMTIME;
+ inode->i_generation = generation;
+ fuse_init_inode(inode, attr, fc);
+ unlock_new_inode(inode);
+ } else if (fuse_stale_inode(inode, generation, attr)) {
+ /* nodeid was reused, any I/O on the old inode should fail */
+ fuse_make_bad(inode);
+ iput(inode);
+ goto retry;
+ }
+ fi = get_fuse_inode(inode);
+ spin_lock(&fi->lock);
+ fi->nlookup++;
+ spin_unlock(&fi->lock);
+done:
+ fuse_change_attributes(inode, attr, NULL, attr_valid, attr_version);
+
+ return inode;
+}
+
+struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid,
+ struct fuse_mount **fm)
+{
+ struct fuse_mount *fm_iter;
+ struct inode *inode;
+
+ WARN_ON(!rwsem_is_locked(&fc->killsb));
+ list_for_each_entry(fm_iter, &fc->mounts, fc_entry) {
+ if (!fm_iter->sb)
+ continue;
+
+ inode = ilookup5(fm_iter->sb, nodeid, fuse_inode_eq, &nodeid);
+ if (inode) {
+ if (fm)
+ *fm = fm_iter;
+ return inode;
+ }
+ }
+
+ return NULL;
+}
+
+int fuse_reverse_inval_inode(struct fuse_conn *fc, u64 nodeid,
+ loff_t offset, loff_t len)
+{
+ struct fuse_inode *fi;
+ struct inode *inode;
+ pgoff_t pg_start;
+ pgoff_t pg_end;
+
+ inode = fuse_ilookup(fc, nodeid, NULL);
+ if (!inode)
+ return -ENOENT;
+
+ fi = get_fuse_inode(inode);
+ spin_lock(&fi->lock);
+ fi->attr_version = atomic64_inc_return(&fc->attr_version);
+ spin_unlock(&fi->lock);
+
+ fuse_invalidate_attr(inode);
+ forget_all_cached_acls(inode);
+ if (offset >= 0) {
+ pg_start = offset >> PAGE_SHIFT;
+ if (len <= 0)
+ pg_end = -1;
+ else
+ pg_end = (offset + len - 1) >> PAGE_SHIFT;
+ invalidate_inode_pages2_range(inode->i_mapping,
+ pg_start, pg_end);
+ }
+ iput(inode);
+ return 0;
+}
+
+bool fuse_lock_inode(struct inode *inode)
+{
+ bool locked = false;
+
+ if (!get_fuse_conn(inode)->parallel_dirops) {
+ mutex_lock(&get_fuse_inode(inode)->mutex);
+ locked = true;
+ }
+
+ return locked;
+}
+
+void fuse_unlock_inode(struct inode *inode, bool locked)
+{
+ if (locked)
+ mutex_unlock(&get_fuse_inode(inode)->mutex);
+}
+
+static void fuse_umount_begin(struct super_block *sb)
+{
+ struct fuse_conn *fc = get_fuse_conn_super(sb);
+
+ if (fc->no_force_umount)
+ return;
+
+ fuse_abort_conn(fc);
+
+ // Only retire block-device-based superblocks.
+ if (sb->s_bdev != NULL)
+ retire_super(sb);
+}
+
+static void fuse_send_destroy(struct fuse_mount *fm)
+{
+ if (fm->fc->conn_init) {
+ FUSE_ARGS(args);
+
+ args.opcode = FUSE_DESTROY;
+ args.force = true;
+ args.nocreds = true;
+ fuse_simple_request(fm, &args);
+ }
+}
+
+static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
+{
+ stbuf->f_type = FUSE_SUPER_MAGIC;
+ stbuf->f_bsize = attr->bsize;
+ stbuf->f_frsize = attr->frsize;
+ stbuf->f_blocks = attr->blocks;
+ stbuf->f_bfree = attr->bfree;
+ stbuf->f_bavail = attr->bavail;
+ stbuf->f_files = attr->files;
+ stbuf->f_ffree = attr->ffree;
+ stbuf->f_namelen = attr->namelen;
+ /* fsid is left zero */
+}
+
+static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct fuse_mount *fm = get_fuse_mount_super(sb);
+ FUSE_ARGS(args);
+ struct fuse_statfs_out outarg;
+ int err;
+
+ if (!fuse_allow_current_process(fm->fc)) {
+ buf->f_type = FUSE_SUPER_MAGIC;
+ return 0;
+ }
+
+ memset(&outarg, 0, sizeof(outarg));
+ args.in_numargs = 0;
+ args.opcode = FUSE_STATFS;
+ args.nodeid = get_node_id(d_inode(dentry));
+ args.out_numargs = 1;
+ args.out_args[0].size = sizeof(outarg);
+ args.out_args[0].value = &outarg;
+ err = fuse_simple_request(fm, &args);
+ if (!err)
+ convert_fuse_statfs(buf, &outarg.st);
+ return err;
+}
+
+static struct fuse_sync_bucket *fuse_sync_bucket_alloc(void)
+{
+ struct fuse_sync_bucket *bucket;
+
+ bucket = kzalloc(sizeof(*bucket), GFP_KERNEL | __GFP_NOFAIL);
+ if (bucket) {
+ init_waitqueue_head(&bucket->waitq);
+ /* Initial active count */
+ atomic_set(&bucket->count, 1);
+ }
+ return bucket;
+}
+
+static void fuse_sync_fs_writes(struct fuse_conn *fc)
+{
+ struct fuse_sync_bucket *bucket, *new_bucket;
+ int count;
+
+ new_bucket = fuse_sync_bucket_alloc();
+ spin_lock(&fc->lock);
+ bucket = rcu_dereference_protected(fc->curr_bucket, 1);
+ count = atomic_read(&bucket->count);
+ WARN_ON(count < 1);
+ /* No outstanding writes? */
+ if (count == 1) {
+ spin_unlock(&fc->lock);
+ kfree(new_bucket);
+ return;
+ }
+
+ /*
+ * Completion of new bucket depends on completion of this bucket, so add
+ * one more count.
+ */
+ atomic_inc(&new_bucket->count);
+ rcu_assign_pointer(fc->curr_bucket, new_bucket);
+ spin_unlock(&fc->lock);
+ /*
+ * Drop initial active count. At this point if all writes in this and
+ * ancestor buckets complete, the count will go to zero and this task
+ * will be woken up.
+ */
+ atomic_dec(&bucket->count);
+
+ wait_event(bucket->waitq, atomic_read(&bucket->count) == 0);
+
+ /* Drop temp count on descendant bucket */
+ fuse_sync_bucket_dec(new_bucket);
+ kfree_rcu(bucket, rcu);
+}
+
+static int fuse_sync_fs(struct super_block *sb, int wait)
+{
+ struct fuse_mount *fm = get_fuse_mount_super(sb);
+ struct fuse_conn *fc = fm->fc;
+ struct fuse_syncfs_in inarg;
+ FUSE_ARGS(args);
+ int err;
+
+ /*
+ * Userspace cannot handle the wait == 0 case. Avoid a
+ * gratuitous roundtrip.
+ */
+ if (!wait)
+ return 0;
+
+ /* The filesystem is being unmounted. Nothing to do. */
+ if (!sb->s_root)
+ return 0;
+
+ if (!fc->sync_fs)
+ return 0;
+
+ fuse_sync_fs_writes(fc);
+
+ memset(&inarg, 0, sizeof(inarg));
+ args.in_numargs = 1;
+ args.in_args[0].size = sizeof(inarg);
+ args.in_args[0].value = &inarg;
+ args.opcode = FUSE_SYNCFS;
+ args.nodeid = get_node_id(sb->s_root->d_inode);
+ args.out_numargs = 0;
+
+ err = fuse_simple_request(fm, &args);
+ if (err == -ENOSYS) {
+ fc->sync_fs = 0;
+ err = 0;
+ }
+
+ return err;
+}
+
+enum {
+ OPT_SOURCE,
+ OPT_SUBTYPE,
+ OPT_FD,
+ OPT_ROOTMODE,
+ OPT_USER_ID,
+ OPT_GROUP_ID,
+ OPT_DEFAULT_PERMISSIONS,
+ OPT_ALLOW_OTHER,
+ OPT_MAX_READ,
+ OPT_BLKSIZE,
+ OPT_ERR
+};
+
+static const struct fs_parameter_spec fuse_fs_parameters[] = {
+ fsparam_string ("source", OPT_SOURCE),
+ fsparam_u32 ("fd", OPT_FD),
+ fsparam_u32oct ("rootmode", OPT_ROOTMODE),
+ fsparam_u32 ("user_id", OPT_USER_ID),
+ fsparam_u32 ("group_id", OPT_GROUP_ID),
+ fsparam_flag ("default_permissions", OPT_DEFAULT_PERMISSIONS),
+ fsparam_flag ("allow_other", OPT_ALLOW_OTHER),
+ fsparam_u32 ("max_read", OPT_MAX_READ),
+ fsparam_u32 ("blksize", OPT_BLKSIZE),
+ fsparam_string ("subtype", OPT_SUBTYPE),
+ {}
+};
+
+static int fuse_parse_param(struct fs_context *fsc, struct fs_parameter *param)
+{
+ struct fs_parse_result result;
+ struct fuse_fs_context *ctx = fsc->fs_private;
+ int opt;
+
+ if (fsc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
+ /*
+ * Ignore options coming from mount(MS_REMOUNT) for backward
+ * compatibility.
+ */
+ if (fsc->oldapi)
+ return 0;
+
+ return invalfc(fsc, "No changes allowed in reconfigure");
+ }
+
+ opt = fs_parse(fsc, fuse_fs_parameters, param, &result);
+ if (opt < 0)
+ return opt;
+
+ switch (opt) {
+ case OPT_SOURCE:
+ if (fsc->source)
+ return invalfc(fsc, "Multiple sources specified");
+ fsc->source = param->string;
+ param->string = NULL;
+ break;
+
+ case OPT_SUBTYPE:
+ if (ctx->subtype)
+ return invalfc(fsc, "Multiple subtypes specified");
+ ctx->subtype = param->string;
+ param->string = NULL;
+ return 0;
+
+ case OPT_FD:
+ ctx->fd = result.uint_32;
+ ctx->fd_present = true;
+ break;
+
+ case OPT_ROOTMODE:
+ if (!fuse_valid_type(result.uint_32))
+ return invalfc(fsc, "Invalid rootmode");
+ ctx->rootmode = result.uint_32;
+ ctx->rootmode_present = true;
+ break;
+
+ case OPT_USER_ID:
+ ctx->user_id = make_kuid(fsc->user_ns, result.uint_32);
+ if (!uid_valid(ctx->user_id))
+ return invalfc(fsc, "Invalid user_id");
+ ctx->user_id_present = true;
+ break;
+
+ case OPT_GROUP_ID:
+ ctx->group_id = make_kgid(fsc->user_ns, result.uint_32);
+ if (!gid_valid(ctx->group_id))
+ return invalfc(fsc, "Invalid group_id");
+ ctx->group_id_present = true;
+ break;
+
+ case OPT_DEFAULT_PERMISSIONS:
+ ctx->default_permissions = true;
+ break;
+
+ case OPT_ALLOW_OTHER:
+ ctx->allow_other = true;
+ break;
+
+ case OPT_MAX_READ:
+ ctx->max_read = result.uint_32;
+ break;
+
+ case OPT_BLKSIZE:
+ if (!ctx->is_bdev)
+ return invalfc(fsc, "blksize only supported for fuseblk");
+ ctx->blksize = result.uint_32;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void fuse_free_fsc(struct fs_context *fsc)
+{
+ struct fuse_fs_context *ctx = fsc->fs_private;
+
+ if (ctx) {
+ kfree(ctx->subtype);
+ kfree(ctx);
+ }
+}
+
+static int fuse_show_options(struct seq_file *m, struct dentry *root)
+{
+ struct super_block *sb = root->d_sb;
+ struct fuse_conn *fc = get_fuse_conn_super(sb);
+
+ if (fc->legacy_opts_show) {
+ seq_printf(m, ",user_id=%u",
+ from_kuid_munged(fc->user_ns, fc->user_id));
+ seq_printf(m, ",group_id=%u",
+ from_kgid_munged(fc->user_ns, fc->group_id));
+ if (fc->default_permissions)
+ seq_puts(m, ",default_permissions");
+ if (fc->allow_other)
+ seq_puts(m, ",allow_other");
+ if (fc->max_read != ~0)
+ seq_printf(m, ",max_read=%u", fc->max_read);
+ if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
+ seq_printf(m, ",blksize=%lu", sb->s_blocksize);
+ }
+#ifdef CONFIG_FUSE_DAX
+ if (fc->dax_mode == FUSE_DAX_ALWAYS)
+ seq_puts(m, ",dax=always");
+ else if (fc->dax_mode == FUSE_DAX_NEVER)
+ seq_puts(m, ",dax=never");
+ else if (fc->dax_mode == FUSE_DAX_INODE_USER)
+ seq_puts(m, ",dax=inode");
+#endif
+
+ return 0;
+}
+
+static void fuse_iqueue_init(struct fuse_iqueue *fiq,
+ const struct fuse_iqueue_ops *ops,
+ void *priv)
+{
+ memset(fiq, 0, sizeof(struct fuse_iqueue));
+ spin_lock_init(&fiq->lock);
+ init_waitqueue_head(&fiq->waitq);
+ INIT_LIST_HEAD(&fiq->pending);
+ INIT_LIST_HEAD(&fiq->interrupts);
+ fiq->forget_list_tail = &fiq->forget_list_head;
+ fiq->connected = 1;
+ fiq->ops = ops;
+ fiq->priv = priv;
+}
+
+static void fuse_pqueue_init(struct fuse_pqueue *fpq)
+{
+ unsigned int i;
+
+ spin_lock_init(&fpq->lock);
+ for (i = 0; i < FUSE_PQ_HASH_SIZE; i++)
+ INIT_LIST_HEAD(&fpq->processing[i]);
+ INIT_LIST_HEAD(&fpq->io);
+ fpq->connected = 1;
+}
+
+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)
+{
+ memset(fc, 0, sizeof(*fc));
+ spin_lock_init(&fc->lock);
+ spin_lock_init(&fc->bg_lock);
+ init_rwsem(&fc->killsb);
+ refcount_set(&fc->count, 1);
+ atomic_set(&fc->dev_count, 1);
+ init_waitqueue_head(&fc->blocked_waitq);
+ fuse_iqueue_init(&fc->iq, fiq_ops, fiq_priv);
+ INIT_LIST_HEAD(&fc->bg_queue);
+ INIT_LIST_HEAD(&fc->entry);
+ INIT_LIST_HEAD(&fc->devices);
+ atomic_set(&fc->num_waiting, 0);
+ fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
+ fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
+ atomic64_set(&fc->khctr, 0);
+ fc->polled_files = RB_ROOT;
+ fc->blocked = 0;
+ fc->initialized = 0;
+ fc->connected = 1;
+ atomic64_set(&fc->attr_version, 1);
+ get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
+ fc->pid_ns = get_pid_ns(task_active_pid_ns(current));
+ fc->user_ns = get_user_ns(user_ns);
+ fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ;
+ fc->max_pages_limit = FUSE_MAX_MAX_PAGES;
+
+ INIT_LIST_HEAD(&fc->mounts);
+ list_add(&fm->fc_entry, &fc->mounts);
+ fm->fc = fc;
+}
+EXPORT_SYMBOL_GPL(fuse_conn_init);
+
+void fuse_conn_put(struct fuse_conn *fc)
+{
+ if (refcount_dec_and_test(&fc->count)) {
+ struct fuse_iqueue *fiq = &fc->iq;
+ struct fuse_sync_bucket *bucket;
+
+ if (IS_ENABLED(CONFIG_FUSE_DAX))
+ fuse_dax_conn_free(fc);
+ if (fiq->ops->release)
+ fiq->ops->release(fiq);
+ put_pid_ns(fc->pid_ns);
+ put_user_ns(fc->user_ns);
+ bucket = rcu_dereference_protected(fc->curr_bucket, 1);
+ if (bucket) {
+ WARN_ON(atomic_read(&bucket->count) != 1);
+ kfree(bucket);
+ }
+ fc->release(fc);
+ }
+}
+EXPORT_SYMBOL_GPL(fuse_conn_put);
+
+struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
+{
+ refcount_inc(&fc->count);
+ return fc;
+}
+EXPORT_SYMBOL_GPL(fuse_conn_get);
+
+static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
+{
+ struct fuse_attr attr;
+ memset(&attr, 0, sizeof(attr));
+
+ attr.mode = mode;
+ attr.ino = FUSE_ROOT_ID;
+ attr.nlink = 1;
+ return fuse_iget(sb, 1, 0, &attr, 0, 0);
+}
+
+struct fuse_inode_handle {
+ u64 nodeid;
+ u32 generation;
+};
+
+static struct dentry *fuse_get_dentry(struct super_block *sb,
+ struct fuse_inode_handle *handle)
+{
+ struct fuse_conn *fc = get_fuse_conn_super(sb);
+ struct inode *inode;
+ struct dentry *entry;
+ int err = -ESTALE;
+
+ if (handle->nodeid == 0)
+ goto out_err;
+
+ inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
+ if (!inode) {
+ struct fuse_entry_out outarg;
+ const struct qstr name = QSTR_INIT(".", 1);
+
+ if (!fc->export_support)
+ goto out_err;
+
+ err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
+ &inode);
+ if (err && err != -ENOENT)
+ goto out_err;
+ if (err || !inode) {
+ err = -ESTALE;
+ goto out_err;
+ }
+ err = -EIO;
+ if (get_node_id(inode) != handle->nodeid)
+ goto out_iput;
+ }
+ err = -ESTALE;
+ if (inode->i_generation != handle->generation)
+ goto out_iput;
+
+ entry = d_obtain_alias(inode);
+ if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID)
+ fuse_invalidate_entry_cache(entry);
+
+ return entry;
+
+ out_iput:
+ iput(inode);
+ out_err:
+ return ERR_PTR(err);
+}
+
+static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len,
+ struct inode *parent)
+{
+ int len = parent ? 6 : 3;
+ u64 nodeid;
+ u32 generation;
+
+ if (*max_len < len) {
+ *max_len = len;
+ return FILEID_INVALID;
+ }
+
+ nodeid = get_fuse_inode(inode)->nodeid;
+ generation = inode->i_generation;
+
+ fh[0] = (u32)(nodeid >> 32);
+ fh[1] = (u32)(nodeid & 0xffffffff);
+ fh[2] = generation;
+
+ if (parent) {
+ nodeid = get_fuse_inode(parent)->nodeid;
+ generation = parent->i_generation;
+
+ fh[3] = (u32)(nodeid >> 32);
+ fh[4] = (u32)(nodeid & 0xffffffff);
+ fh[5] = generation;
+ }
+
+ *max_len = len;
+ return parent ? 0x82 : 0x81;
+}
+
+static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
+ struct fid *fid, int fh_len, int fh_type)
+{
+ struct fuse_inode_handle handle;
+
+ if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
+ return NULL;
+
+ handle.nodeid = (u64) fid->raw[0] << 32;
+ handle.nodeid |= (u64) fid->raw[1];
+ handle.generation = fid->raw[2];
+ return fuse_get_dentry(sb, &handle);
+}
+
+static struct dentry *fuse_fh_to_parent(struct super_block *sb,
+ struct fid *fid, int fh_len, int fh_type)
+{
+ struct fuse_inode_handle parent;
+
+ if (fh_type != 0x82 || fh_len < 6)
+ return NULL;
+
+ parent.nodeid = (u64) fid->raw[3] << 32;
+ parent.nodeid |= (u64) fid->raw[4];
+ parent.generation = fid->raw[5];
+ return fuse_get_dentry(sb, &parent);
+}
+
+static struct dentry *fuse_get_parent(struct dentry *child)
+{
+ struct inode *child_inode = d_inode(child);
+ struct fuse_conn *fc = get_fuse_conn(child_inode);
+ struct inode *inode;
+ struct dentry *parent;
+ struct fuse_entry_out outarg;
+ int err;
+
+ if (!fc->export_support)
+ return ERR_PTR(-ESTALE);
+
+ err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
+ &dotdot_name, &outarg, &inode);
+ if (err) {
+ if (err == -ENOENT)
+ return ERR_PTR(-ESTALE);
+ return ERR_PTR(err);
+ }
+
+ parent = d_obtain_alias(inode);
+ if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID)
+ fuse_invalidate_entry_cache(parent);
+
+ return parent;
+}
+
+static const struct export_operations fuse_export_operations = {
+ .fh_to_dentry = fuse_fh_to_dentry,
+ .fh_to_parent = fuse_fh_to_parent,
+ .encode_fh = fuse_encode_fh,
+ .get_parent = fuse_get_parent,
+};
+
+static const struct super_operations fuse_super_operations = {
+ .alloc_inode = fuse_alloc_inode,
+ .free_inode = fuse_free_inode,
+ .evict_inode = fuse_evict_inode,
+ .write_inode = fuse_write_inode,
+ .drop_inode = generic_delete_inode,
+ .umount_begin = fuse_umount_begin,
+ .statfs = fuse_statfs,
+ .sync_fs = fuse_sync_fs,
+ .show_options = fuse_show_options,
+};
+
+static void sanitize_global_limit(unsigned *limit)
+{
+ /*
+ * The default maximum number of async requests is calculated to consume
+ * 1/2^13 of the total memory, assuming 392 bytes per request.
+ */
+ if (*limit == 0)
+ *limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 392;
+
+ if (*limit >= 1 << 16)
+ *limit = (1 << 16) - 1;
+}
+
+static int set_global_limit(const char *val, const struct kernel_param *kp)
+{
+ int rv;
+
+ rv = param_set_uint(val, kp);
+ if (rv)
+ return rv;
+
+ sanitize_global_limit((unsigned *)kp->arg);
+
+ return 0;
+}
+
+static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg)
+{
+ int cap_sys_admin = capable(CAP_SYS_ADMIN);
+
+ if (arg->minor < 13)
+ return;
+
+ sanitize_global_limit(&max_user_bgreq);
+ sanitize_global_limit(&max_user_congthresh);
+
+ spin_lock(&fc->bg_lock);
+ if (arg->max_background) {
+ fc->max_background = arg->max_background;
+
+ if (!cap_sys_admin && fc->max_background > max_user_bgreq)
+ fc->max_background = max_user_bgreq;
+ }
+ if (arg->congestion_threshold) {
+ fc->congestion_threshold = arg->congestion_threshold;
+
+ if (!cap_sys_admin &&
+ fc->congestion_threshold > max_user_congthresh)
+ fc->congestion_threshold = max_user_congthresh;
+ }
+ spin_unlock(&fc->bg_lock);
+}
+
+struct fuse_init_args {
+ struct fuse_args args;
+ struct fuse_init_in in;
+ struct fuse_init_out out;
+};
+
+static void process_init_reply(struct fuse_mount *fm, struct fuse_args *args,
+ int error)
+{
+ struct fuse_conn *fc = fm->fc;
+ struct fuse_init_args *ia = container_of(args, typeof(*ia), args);
+ struct fuse_init_out *arg = &ia->out;
+ bool ok = true;
+
+ if (error || arg->major != FUSE_KERNEL_VERSION)
+ ok = false;
+ else {
+ unsigned long ra_pages;
+
+ process_init_limits(fc, arg);
+
+ if (arg->minor >= 6) {
+ u64 flags = arg->flags;
+
+ if (flags & FUSE_INIT_EXT)
+ flags |= (u64) arg->flags2 << 32;
+
+ ra_pages = arg->max_readahead / PAGE_SIZE;
+ if (flags & FUSE_ASYNC_READ)
+ fc->async_read = 1;
+ if (!(flags & FUSE_POSIX_LOCKS))
+ fc->no_lock = 1;
+ if (arg->minor >= 17) {
+ if (!(flags & FUSE_FLOCK_LOCKS))
+ fc->no_flock = 1;
+ } else {
+ if (!(flags & FUSE_POSIX_LOCKS))
+ fc->no_flock = 1;
+ }
+ if (flags & FUSE_ATOMIC_O_TRUNC)
+ fc->atomic_o_trunc = 1;
+ if (arg->minor >= 9) {
+ /* LOOKUP has dependency on proto version */
+ if (flags & FUSE_EXPORT_SUPPORT)
+ fc->export_support = 1;
+ }
+ if (flags & FUSE_BIG_WRITES)
+ fc->big_writes = 1;
+ if (flags & FUSE_DONT_MASK)
+ fc->dont_mask = 1;
+ if (flags & FUSE_AUTO_INVAL_DATA)
+ fc->auto_inval_data = 1;
+ else if (flags & FUSE_EXPLICIT_INVAL_DATA)
+ fc->explicit_inval_data = 1;
+ if (flags & FUSE_DO_READDIRPLUS) {
+ fc->do_readdirplus = 1;
+ if (flags & FUSE_READDIRPLUS_AUTO)
+ fc->readdirplus_auto = 1;
+ }
+ if (flags & FUSE_ASYNC_DIO)
+ fc->async_dio = 1;
+ if (flags & FUSE_WRITEBACK_CACHE)
+ fc->writeback_cache = 1;
+ if (flags & FUSE_PARALLEL_DIROPS)
+ fc->parallel_dirops = 1;
+ if (flags & FUSE_HANDLE_KILLPRIV)
+ fc->handle_killpriv = 1;
+ if (arg->time_gran && arg->time_gran <= 1000000000)
+ fm->sb->s_time_gran = arg->time_gran;
+ if ((flags & FUSE_POSIX_ACL)) {
+ fc->default_permissions = 1;
+ fc->posix_acl = 1;
+ }
+ if (flags & FUSE_CACHE_SYMLINKS)
+ fc->cache_symlinks = 1;
+ if (flags & FUSE_ABORT_ERROR)
+ fc->abort_err = 1;
+ if (flags & FUSE_MAX_PAGES) {
+ fc->max_pages =
+ min_t(unsigned int, fc->max_pages_limit,
+ max_t(unsigned int, arg->max_pages, 1));
+ }
+ if (IS_ENABLED(CONFIG_FUSE_DAX)) {
+ if (flags & FUSE_MAP_ALIGNMENT &&
+ !fuse_dax_check_alignment(fc, arg->map_alignment)) {
+ ok = false;
+ }
+ if (flags & FUSE_HAS_INODE_DAX)
+ fc->inode_dax = 1;
+ }
+ if (flags & FUSE_HANDLE_KILLPRIV_V2) {
+ fc->handle_killpriv_v2 = 1;
+ fm->sb->s_flags |= SB_NOSEC;
+ }
+ if (flags & FUSE_SETXATTR_EXT)
+ fc->setxattr_ext = 1;
+ if (flags & FUSE_SECURITY_CTX)
+ fc->init_security = 1;
+ if (flags & FUSE_CREATE_SUPP_GROUP)
+ fc->create_supp_group = 1;
+ if (flags & FUSE_DIRECT_IO_ALLOW_MMAP)
+ fc->direct_io_allow_mmap = 1;
+ } else {
+ ra_pages = fc->max_read / PAGE_SIZE;
+ fc->no_lock = 1;
+ fc->no_flock = 1;
+ }
+
+ fm->sb->s_bdi->ra_pages =
+ min(fm->sb->s_bdi->ra_pages, ra_pages);
+ fc->minor = arg->minor;
+ fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
+ fc->max_write = max_t(unsigned, 4096, fc->max_write);
+ fc->conn_init = 1;
+ }
+ kfree(ia);
+
+ if (!ok) {
+ fc->conn_init = 0;
+ fc->conn_error = 1;
+ }
+
+ fuse_set_initialized(fc);
+ wake_up_all(&fc->blocked_waitq);
+}
+
+void fuse_send_init(struct fuse_mount *fm)
+{
+ struct fuse_init_args *ia;
+ u64 flags;
+
+ ia = kzalloc(sizeof(*ia), GFP_KERNEL | __GFP_NOFAIL);
+
+ ia->in.major = FUSE_KERNEL_VERSION;
+ ia->in.minor = FUSE_KERNEL_MINOR_VERSION;
+ ia->in.max_readahead = fm->sb->s_bdi->ra_pages * PAGE_SIZE;
+ flags =
+ FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
+ FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
+ FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
+ FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
+ FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
+ FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT |
+ FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL |
+ FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS |
+ FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA |
+ FUSE_HANDLE_KILLPRIV_V2 | FUSE_SETXATTR_EXT | FUSE_INIT_EXT |
+ FUSE_SECURITY_CTX | FUSE_CREATE_SUPP_GROUP |
+ FUSE_HAS_EXPIRE_ONLY | FUSE_DIRECT_IO_ALLOW_MMAP;
+#ifdef CONFIG_FUSE_DAX
+ if (fm->fc->dax)
+ flags |= FUSE_MAP_ALIGNMENT;
+ if (fuse_is_inode_dax_mode(fm->fc->dax_mode))
+ flags |= FUSE_HAS_INODE_DAX;
+#endif
+ if (fm->fc->auto_submounts)
+ flags |= FUSE_SUBMOUNTS;
+
+ ia->in.flags = flags;
+ ia->in.flags2 = flags >> 32;
+
+ ia->args.opcode = FUSE_INIT;
+ ia->args.in_numargs = 1;
+ ia->args.in_args[0].size = sizeof(ia->in);
+ ia->args.in_args[0].value = &ia->in;
+ ia->args.out_numargs = 1;
+ /* Variable length argument used for backward compatibility
+ with interface version < 7.5. Rest of init_out is zeroed
+ by do_get_request(), so a short reply is not a problem */
+ ia->args.out_argvar = true;
+ ia->args.out_args[0].size = sizeof(ia->out);
+ ia->args.out_args[0].value = &ia->out;
+ ia->args.force = true;
+ ia->args.nocreds = true;
+ ia->args.end = process_init_reply;
+
+ if (fuse_simple_background(fm, &ia->args, GFP_KERNEL) != 0)
+ process_init_reply(fm, &ia->args, -ENOTCONN);
+}
+EXPORT_SYMBOL_GPL(fuse_send_init);
+
+void fuse_free_conn(struct fuse_conn *fc)
+{
+ WARN_ON(!list_empty(&fc->devices));
+ kfree_rcu(fc, rcu);
+}
+EXPORT_SYMBOL_GPL(fuse_free_conn);
+
+static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
+{
+ int err;
+ char *suffix = "";
+
+ if (sb->s_bdev) {
+ suffix = "-fuseblk";
+ /*
+ * sb->s_bdi points to blkdev's bdi however we want to redirect
+ * it to our private bdi...
+ */
+ bdi_put(sb->s_bdi);
+ sb->s_bdi = &noop_backing_dev_info;
+ }
+ err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev),
+ MINOR(fc->dev), suffix);
+ if (err)
+ return err;
+
+ /* fuse does it's own writeback accounting */
+ sb->s_bdi->capabilities &= ~BDI_CAP_WRITEBACK_ACCT;
+ sb->s_bdi->capabilities |= BDI_CAP_STRICTLIMIT;
+
+ /*
+ * For a single fuse filesystem use max 1% of dirty +
+ * writeback threshold.
+ *
+ * This gives about 1M of write buffer for memory maps on a
+ * machine with 1G and 10% dirty_ratio, which should be more
+ * than enough.
+ *
+ * Privileged users can raise it by writing to
+ *
+ * /sys/class/bdi/<bdi>/max_ratio
+ */
+ bdi_set_max_ratio(sb->s_bdi, 1);
+
+ return 0;
+}
+
+struct fuse_dev *fuse_dev_alloc(void)
+{
+ struct fuse_dev *fud;
+ struct list_head *pq;
+
+ fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL);
+ if (!fud)
+ return NULL;
+
+ pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL);
+ if (!pq) {
+ kfree(fud);
+ return NULL;
+ }
+
+ fud->pq.processing = pq;
+ fuse_pqueue_init(&fud->pq);
+
+ return fud;
+}
+EXPORT_SYMBOL_GPL(fuse_dev_alloc);
+
+void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc)
+{
+ fud->fc = fuse_conn_get(fc);
+ spin_lock(&fc->lock);
+ list_add_tail(&fud->entry, &fc->devices);
+ spin_unlock(&fc->lock);
+}
+EXPORT_SYMBOL_GPL(fuse_dev_install);
+
+struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc)
+{
+ struct fuse_dev *fud;
+
+ fud = fuse_dev_alloc();
+ if (!fud)
+ return NULL;
+
+ fuse_dev_install(fud, fc);
+ return fud;
+}
+EXPORT_SYMBOL_GPL(fuse_dev_alloc_install);
+
+void fuse_dev_free(struct fuse_dev *fud)
+{
+ struct fuse_conn *fc = fud->fc;
+
+ if (fc) {
+ spin_lock(&fc->lock);
+ list_del(&fud->entry);
+ spin_unlock(&fc->lock);
+
+ fuse_conn_put(fc);
+ }
+ kfree(fud->pq.processing);
+ kfree(fud);
+}
+EXPORT_SYMBOL_GPL(fuse_dev_free);
+
+static void fuse_fill_attr_from_inode(struct fuse_attr *attr,
+ const struct fuse_inode *fi)
+{
+ struct timespec64 ctime = inode_get_ctime(&fi->inode);
+
+ *attr = (struct fuse_attr){
+ .ino = fi->inode.i_ino,
+ .size = fi->inode.i_size,
+ .blocks = fi->inode.i_blocks,
+ .atime = fi->inode.i_atime.tv_sec,
+ .mtime = fi->inode.i_mtime.tv_sec,
+ .ctime = ctime.tv_sec,
+ .atimensec = fi->inode.i_atime.tv_nsec,
+ .mtimensec = fi->inode.i_mtime.tv_nsec,
+ .ctimensec = ctime.tv_nsec,
+ .mode = fi->inode.i_mode,
+ .nlink = fi->inode.i_nlink,
+ .uid = fi->inode.i_uid.val,
+ .gid = fi->inode.i_gid.val,
+ .rdev = fi->inode.i_rdev,
+ .blksize = 1u << fi->inode.i_blkbits,
+ };
+}
+
+static void fuse_sb_defaults(struct super_block *sb)
+{
+ sb->s_magic = FUSE_SUPER_MAGIC;
+ sb->s_op = &fuse_super_operations;
+ sb->s_xattr = fuse_xattr_handlers;
+ sb->s_maxbytes = MAX_LFS_FILESIZE;
+ sb->s_time_gran = 1;
+ sb->s_export_op = &fuse_export_operations;
+ sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE;
+ if (sb->s_user_ns != &init_user_ns)
+ sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER;
+ sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION);
+}
+
+static int fuse_fill_super_submount(struct super_block *sb,
+ struct fuse_inode *parent_fi)
+{
+ struct fuse_mount *fm = get_fuse_mount_super(sb);
+ struct super_block *parent_sb = parent_fi->inode.i_sb;
+ struct fuse_attr root_attr;
+ struct inode *root;
+ struct fuse_submount_lookup *sl;
+ struct fuse_inode *fi;
+
+ fuse_sb_defaults(sb);
+ fm->sb = sb;
+
+ WARN_ON(sb->s_bdi != &noop_backing_dev_info);
+ sb->s_bdi = bdi_get(parent_sb->s_bdi);
+
+ sb->s_xattr = parent_sb->s_xattr;
+ sb->s_time_gran = parent_sb->s_time_gran;
+ sb->s_blocksize = parent_sb->s_blocksize;
+ sb->s_blocksize_bits = parent_sb->s_blocksize_bits;
+ sb->s_subtype = kstrdup(parent_sb->s_subtype, GFP_KERNEL);
+ if (parent_sb->s_subtype && !sb->s_subtype)
+ return -ENOMEM;
+
+ fuse_fill_attr_from_inode(&root_attr, parent_fi);
+ root = fuse_iget(sb, parent_fi->nodeid, 0, &root_attr, 0, 0);
+ /*
+ * This inode is just a duplicate, so it is not looked up and
+ * its nlookup should not be incremented. fuse_iget() does
+ * that, though, so undo it here.
+ */
+ fi = get_fuse_inode(root);
+ fi->nlookup--;
+
+ sb->s_d_op = &fuse_dentry_operations;
+ sb->s_root = d_make_root(root);
+ if (!sb->s_root)
+ return -ENOMEM;
+
+ /*
+ * Grab the parent's submount_lookup pointer and take a
+ * reference on the shared nlookup from the parent. This is to
+ * prevent the last forget for this nodeid from getting
+ * triggered until all users have finished with it.
+ */
+ sl = parent_fi->submount_lookup;
+ WARN_ON(!sl);
+ if (sl) {
+ refcount_inc(&sl->count);
+ fi->submount_lookup = sl;
+ }
+
+ return 0;
+}
+
+/* Filesystem context private data holds the FUSE inode of the mount point */
+static int fuse_get_tree_submount(struct fs_context *fsc)
+{
+ struct fuse_mount *fm;
+ struct fuse_inode *mp_fi = fsc->fs_private;
+ struct fuse_conn *fc = get_fuse_conn(&mp_fi->inode);
+ struct super_block *sb;
+ int err;
+
+ fm = kzalloc(sizeof(struct fuse_mount), GFP_KERNEL);
+ if (!fm)
+ return -ENOMEM;
+
+ fm->fc = fuse_conn_get(fc);
+ fsc->s_fs_info = fm;
+ sb = sget_fc(fsc, NULL, set_anon_super_fc);
+ if (fsc->s_fs_info)
+ fuse_mount_destroy(fm);
+ if (IS_ERR(sb))
+ return PTR_ERR(sb);
+
+ /* Initialize superblock, making @mp_fi its root */
+ err = fuse_fill_super_submount(sb, mp_fi);
+ if (err) {
+ deactivate_locked_super(sb);
+ return err;
+ }
+
+ down_write(&fc->killsb);
+ list_add_tail(&fm->fc_entry, &fc->mounts);
+ up_write(&fc->killsb);
+
+ sb->s_flags |= SB_ACTIVE;
+ fsc->root = dget(sb->s_root);
+
+ return 0;
+}
+
+static const struct fs_context_operations fuse_context_submount_ops = {
+ .get_tree = fuse_get_tree_submount,
+};
+
+int fuse_init_fs_context_submount(struct fs_context *fsc)
+{
+ fsc->ops = &fuse_context_submount_ops;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(fuse_init_fs_context_submount);
+
+int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx)
+{
+ struct fuse_dev *fud = NULL;
+ struct fuse_mount *fm = get_fuse_mount_super(sb);
+ struct fuse_conn *fc = fm->fc;
+ struct inode *root;
+ struct dentry *root_dentry;
+ int err;
+
+ err = -EINVAL;
+ if (sb->s_flags & SB_MANDLOCK)
+ goto err;
+
+ rcu_assign_pointer(fc->curr_bucket, fuse_sync_bucket_alloc());
+ fuse_sb_defaults(sb);
+
+ if (ctx->is_bdev) {
+#ifdef CONFIG_BLOCK
+ err = -EINVAL;
+ if (!sb_set_blocksize(sb, ctx->blksize))
+ goto err;
+#endif
+ } else {
+ sb->s_blocksize = PAGE_SIZE;
+ sb->s_blocksize_bits = PAGE_SHIFT;
+ }
+
+ sb->s_subtype = ctx->subtype;
+ ctx->subtype = NULL;
+ if (IS_ENABLED(CONFIG_FUSE_DAX)) {
+ err = fuse_dax_conn_alloc(fc, ctx->dax_mode, ctx->dax_dev);
+ if (err)
+ goto err;
+ }
+
+ if (ctx->fudptr) {
+ err = -ENOMEM;
+ fud = fuse_dev_alloc_install(fc);
+ if (!fud)
+ goto err_free_dax;
+ }
+
+ fc->dev = sb->s_dev;
+ fm->sb = sb;
+ err = fuse_bdi_init(fc, sb);
+ if (err)
+ goto err_dev_free;
+
+ /* Handle umasking inside the fuse code */
+ if (sb->s_flags & SB_POSIXACL)
+ fc->dont_mask = 1;
+ sb->s_flags |= SB_POSIXACL;
+
+ fc->default_permissions = ctx->default_permissions;
+ fc->allow_other = ctx->allow_other;
+ fc->user_id = ctx->user_id;
+ fc->group_id = ctx->group_id;
+ fc->legacy_opts_show = ctx->legacy_opts_show;
+ fc->max_read = max_t(unsigned int, 4096, ctx->max_read);
+ fc->destroy = ctx->destroy;
+ fc->no_control = ctx->no_control;
+ fc->no_force_umount = ctx->no_force_umount;
+
+ err = -ENOMEM;
+ root = fuse_get_root_inode(sb, ctx->rootmode);
+ sb->s_d_op = &fuse_root_dentry_operations;
+ root_dentry = d_make_root(root);
+ if (!root_dentry)
+ goto err_dev_free;
+ /* Root dentry doesn't have .d_revalidate */
+ sb->s_d_op = &fuse_dentry_operations;
+
+ mutex_lock(&fuse_mutex);
+ err = -EINVAL;
+ if (ctx->fudptr && *ctx->fudptr)
+ goto err_unlock;
+
+ err = fuse_ctl_add_conn(fc);
+ if (err)
+ goto err_unlock;
+
+ list_add_tail(&fc->entry, &fuse_conn_list);
+ sb->s_root = root_dentry;
+ if (ctx->fudptr)
+ *ctx->fudptr = fud;
+ mutex_unlock(&fuse_mutex);
+ return 0;
+
+ err_unlock:
+ mutex_unlock(&fuse_mutex);
+ dput(root_dentry);
+ err_dev_free:
+ if (fud)
+ fuse_dev_free(fud);
+ err_free_dax:
+ if (IS_ENABLED(CONFIG_FUSE_DAX))
+ fuse_dax_conn_free(fc);
+ err:
+ return err;
+}
+EXPORT_SYMBOL_GPL(fuse_fill_super_common);
+
+static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc)
+{
+ struct fuse_fs_context *ctx = fsc->fs_private;
+ int err;
+
+ if (!ctx->file || !ctx->rootmode_present ||
+ !ctx->user_id_present || !ctx->group_id_present)
+ return -EINVAL;
+
+ /*
+ * Require mount to happen from the same user namespace which
+ * opened /dev/fuse to prevent potential attacks.
+ */
+ if ((ctx->file->f_op != &fuse_dev_operations) ||
+ (ctx->file->f_cred->user_ns != sb->s_user_ns))
+ return -EINVAL;
+ ctx->fudptr = &ctx->file->private_data;
+
+ err = fuse_fill_super_common(sb, ctx);
+ if (err)
+ return err;
+ /* file->private_data shall be visible on all CPUs after this */
+ smp_mb();
+ fuse_send_init(get_fuse_mount_super(sb));
+ return 0;
+}
+
+/*
+ * This is the path where user supplied an already initialized fuse dev. In
+ * this case never create a new super if the old one is gone.
+ */
+static int fuse_set_no_super(struct super_block *sb, struct fs_context *fsc)
+{
+ return -ENOTCONN;
+}
+
+static int fuse_test_super(struct super_block *sb, struct fs_context *fsc)
+{
+
+ return fsc->sget_key == get_fuse_conn_super(sb);
+}
+
+static int fuse_get_tree(struct fs_context *fsc)
+{
+ struct fuse_fs_context *ctx = fsc->fs_private;
+ struct fuse_dev *fud;
+ struct fuse_conn *fc;
+ struct fuse_mount *fm;
+ struct super_block *sb;
+ int err;
+
+ fc = kmalloc(sizeof(*fc), GFP_KERNEL);
+ if (!fc)
+ return -ENOMEM;
+
+ fm = kzalloc(sizeof(*fm), GFP_KERNEL);
+ if (!fm) {
+ kfree(fc);
+ return -ENOMEM;
+ }
+
+ fuse_conn_init(fc, fm, fsc->user_ns, &fuse_dev_fiq_ops, NULL);
+ fc->release = fuse_free_conn;
+
+ fsc->s_fs_info = fm;
+
+ if (ctx->fd_present)
+ ctx->file = fget(ctx->fd);
+
+ if (IS_ENABLED(CONFIG_BLOCK) && ctx->is_bdev) {
+ err = get_tree_bdev(fsc, fuse_fill_super);
+ goto out;
+ }
+ /*
+ * While block dev mount can be initialized with a dummy device fd
+ * (found by device name), normal fuse mounts can't
+ */
+ err = -EINVAL;
+ if (!ctx->file)
+ goto out;
+
+ /*
+ * Allow creating a fuse mount with an already initialized fuse
+ * connection
+ */
+ fud = READ_ONCE(ctx->file->private_data);
+ if (ctx->file->f_op == &fuse_dev_operations && fud) {
+ fsc->sget_key = fud->fc;
+ sb = sget_fc(fsc, fuse_test_super, fuse_set_no_super);
+ err = PTR_ERR_OR_ZERO(sb);
+ if (!IS_ERR(sb))
+ fsc->root = dget(sb->s_root);
+ } else {
+ err = get_tree_nodev(fsc, fuse_fill_super);
+ }
+out:
+ if (fsc->s_fs_info)
+ fuse_mount_destroy(fm);
+ if (ctx->file)
+ fput(ctx->file);
+ return err;
+}
+
+static const struct fs_context_operations fuse_context_ops = {
+ .free = fuse_free_fsc,
+ .parse_param = fuse_parse_param,
+ .reconfigure = fuse_reconfigure,
+ .get_tree = fuse_get_tree,
+};
+
+/*
+ * Set up the filesystem mount context.
+ */
+static int fuse_init_fs_context(struct fs_context *fsc)
+{
+ struct fuse_fs_context *ctx;
+
+ ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->max_read = ~0;
+ ctx->blksize = FUSE_DEFAULT_BLKSIZE;
+ ctx->legacy_opts_show = true;
+
+#ifdef CONFIG_BLOCK
+ if (fsc->fs_type == &fuseblk_fs_type) {
+ ctx->is_bdev = true;
+ ctx->destroy = true;
+ }
+#endif
+
+ fsc->fs_private = ctx;
+ fsc->ops = &fuse_context_ops;
+ return 0;
+}
+
+bool fuse_mount_remove(struct fuse_mount *fm)
+{
+ struct fuse_conn *fc = fm->fc;
+ bool last = false;
+
+ down_write(&fc->killsb);
+ list_del_init(&fm->fc_entry);
+ if (list_empty(&fc->mounts))
+ last = true;
+ up_write(&fc->killsb);
+
+ return last;
+}
+EXPORT_SYMBOL_GPL(fuse_mount_remove);
+
+void fuse_conn_destroy(struct fuse_mount *fm)
+{
+ struct fuse_conn *fc = fm->fc;
+
+ if (fc->destroy)
+ fuse_send_destroy(fm);
+
+ fuse_abort_conn(fc);
+ fuse_wait_aborted(fc);
+
+ if (!list_empty(&fc->entry)) {
+ mutex_lock(&fuse_mutex);
+ list_del(&fc->entry);
+ fuse_ctl_remove_conn(fc);
+ mutex_unlock(&fuse_mutex);
+ }
+}
+EXPORT_SYMBOL_GPL(fuse_conn_destroy);
+
+static void fuse_sb_destroy(struct super_block *sb)
+{
+ struct fuse_mount *fm = get_fuse_mount_super(sb);
+ bool last;
+
+ if (sb->s_root) {
+ last = fuse_mount_remove(fm);
+ if (last)
+ fuse_conn_destroy(fm);
+ }
+}
+
+void fuse_mount_destroy(struct fuse_mount *fm)
+{
+ fuse_conn_put(fm->fc);
+ kfree(fm);
+}
+EXPORT_SYMBOL(fuse_mount_destroy);
+
+static void fuse_kill_sb_anon(struct super_block *sb)
+{
+ fuse_sb_destroy(sb);
+ kill_anon_super(sb);
+ fuse_mount_destroy(get_fuse_mount_super(sb));
+}
+
+static struct file_system_type fuse_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "fuse",
+ .fs_flags = FS_HAS_SUBTYPE | FS_USERNS_MOUNT,
+ .init_fs_context = fuse_init_fs_context,
+ .parameters = fuse_fs_parameters,
+ .kill_sb = fuse_kill_sb_anon,
+};
+MODULE_ALIAS_FS("fuse");
+
+#ifdef CONFIG_BLOCK
+static void fuse_kill_sb_blk(struct super_block *sb)
+{
+ fuse_sb_destroy(sb);
+ kill_block_super(sb);
+ fuse_mount_destroy(get_fuse_mount_super(sb));
+}
+
+static struct file_system_type fuseblk_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "fuseblk",
+ .init_fs_context = fuse_init_fs_context,
+ .parameters = fuse_fs_parameters,
+ .kill_sb = fuse_kill_sb_blk,
+ .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
+};
+MODULE_ALIAS_FS("fuseblk");
+
+static inline int register_fuseblk(void)
+{
+ return register_filesystem(&fuseblk_fs_type);
+}
+
+static inline void unregister_fuseblk(void)
+{
+ unregister_filesystem(&fuseblk_fs_type);
+}
+#else
+static inline int register_fuseblk(void)
+{
+ return 0;
+}
+
+static inline void unregister_fuseblk(void)
+{
+}
+#endif
+
+static void fuse_inode_init_once(void *foo)
+{
+ struct inode *inode = foo;
+
+ inode_init_once(inode);
+}
+
+static int __init fuse_fs_init(void)
+{
+ int err;
+
+ fuse_inode_cachep = kmem_cache_create("fuse_inode",
+ sizeof(struct fuse_inode), 0,
+ SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT,
+ fuse_inode_init_once);
+ err = -ENOMEM;
+ if (!fuse_inode_cachep)
+ goto out;
+
+ err = register_fuseblk();
+ if (err)
+ goto out2;
+
+ err = register_filesystem(&fuse_fs_type);
+ if (err)
+ goto out3;
+
+ return 0;
+
+ out3:
+ unregister_fuseblk();
+ out2:
+ kmem_cache_destroy(fuse_inode_cachep);
+ out:
+ return err;
+}
+
+static void fuse_fs_cleanup(void)
+{
+ unregister_filesystem(&fuse_fs_type);
+ unregister_fuseblk();
+
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+ kmem_cache_destroy(fuse_inode_cachep);
+}
+
+static struct kobject *fuse_kobj;
+
+static int fuse_sysfs_init(void)
+{
+ int err;
+
+ fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
+ if (!fuse_kobj) {
+ err = -ENOMEM;
+ goto out_err;
+ }
+
+ err = sysfs_create_mount_point(fuse_kobj, "connections");
+ if (err)
+ goto out_fuse_unregister;
+
+ return 0;
+
+ out_fuse_unregister:
+ kobject_put(fuse_kobj);
+ out_err:
+ return err;
+}
+
+static void fuse_sysfs_cleanup(void)
+{
+ sysfs_remove_mount_point(fuse_kobj, "connections");
+ kobject_put(fuse_kobj);
+}
+
+static int __init fuse_init(void)
+{
+ int res;
+
+ pr_info("init (API version %i.%i)\n",
+ FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
+
+ INIT_LIST_HEAD(&fuse_conn_list);
+ res = fuse_fs_init();
+ if (res)
+ goto err;
+
+ res = fuse_dev_init();
+ if (res)
+ goto err_fs_cleanup;
+
+ res = fuse_sysfs_init();
+ if (res)
+ goto err_dev_cleanup;
+
+ res = fuse_ctl_init();
+ if (res)
+ goto err_sysfs_cleanup;
+
+ sanitize_global_limit(&max_user_bgreq);
+ sanitize_global_limit(&max_user_congthresh);
+
+ return 0;
+
+ err_sysfs_cleanup:
+ fuse_sysfs_cleanup();
+ err_dev_cleanup:
+ fuse_dev_cleanup();
+ err_fs_cleanup:
+ fuse_fs_cleanup();
+ err:
+ return res;
+}
+
+static void __exit fuse_exit(void)
+{
+ pr_debug("exit\n");
+
+ fuse_ctl_cleanup();
+ fuse_sysfs_cleanup();
+ fuse_fs_cleanup();
+ fuse_dev_cleanup();
+}
+
+module_init(fuse_init);
+module_exit(fuse_exit);