fuse/fuse.c

/*
  FUSE: Filesystem in Userspace
  Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>

  This program can be distributed under the terms of the GNU LGPLv2.
  See the file COPYING.LIB
*/


/* For pthread_rwlock_t */
#define _GNU_SOURCE

#include "config.h"
#include "fuse_i.h"
#include "fuse_lowlevel.h"
#include "fuse_opt.h"
#include "fuse_misc.h"
#include "fuse_common_compat.h"
#include "fuse_compat.h"
#include "fuse_kernel.h"

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdbool.h>
#include <unistd.h>
#include <time.h>
#include <fcntl.h>
#include <limits.h>
#include <errno.h>
#include <signal.h>
#include <dlfcn.h>
#include <assert.h>
#include <poll.h>
#include <sys/param.h>
#include <sys/uio.h>
#include <sys/time.h>
#include <sys/mman.h>

#define FUSE_NODE_SLAB 1

#ifndef MAP_ANONYMOUS
#undef FUSE_NODE_SLAB
#endif

#define FUSE_DEFAULT_INTR_SIGNAL SIGUSR1

#define FUSE_UNKNOWN_INO 0xffffffff
#define OFFSET_MAX 0x7fffffffffffffffLL

#define NODE_TABLE_MIN_SIZE 8192

struct fuse_config {
	unsigned int uid;
	unsigned int gid;
	unsigned int  umask;
	double entry_timeout;
	double negative_timeout;
	double attr_timeout;
	double ac_attr_timeout;
	int ac_attr_timeout_set;
	int remember;
	int nopath;
	int debug;
	int hard_remove;
	int use_ino;
	int readdir_ino;
	int set_mode;
	int set_uid;
	int set_gid;
	int direct_io;
	int kernel_cache;
	int auto_cache;
	int intr;
	int intr_signal;
	int help;
	char *modules;
};

struct fuse_fs {
	struct fuse_operations op;
	struct fuse_module *m;
	void *user_data;
	int compat;
	int debug;
};

struct fusemod_so {
	void *handle;
	int ctr;
};

struct lock_queue_element {
	struct lock_queue_element *next;
	pthread_cond_t cond;
	fuse_ino_t nodeid1;
	const char *name1;
	char **path1;
	struct node **wnode1;
	fuse_ino_t nodeid2;
	const char *name2;
	char **path2;
	struct node **wnode2;
	int err;
	bool first_locked : 1;
	bool second_locked : 1;
	bool done : 1;
};

struct node_table {
	struct node **array;
	size_t use;
	size_t size;
	size_t split;
};

#define container_of(ptr, type, member) ({                              \
                        const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                        (type *)( (char *)__mptr - offsetof(type,member) );})

#define list_entry(ptr, type, member)           \
        container_of(ptr, type, member)

struct list_head {
	struct list_head *next;
	struct list_head *prev;
};

struct node_slab {
	struct list_head list;  /* must be the first member */
	struct list_head freelist;
	int used;
};

struct fuse {
	struct fuse_session *se;
	struct node_table name_table;
	struct node_table id_table;
	struct list_head lru_table;
	fuse_ino_t ctr;
	unsigned int generation;
	unsigned int hidectr;
	pthread_mutex_t lock;
	struct fuse_config conf;
	int intr_installed;
	struct fuse_fs *fs;
	int nullpath_ok;
	int utime_omit_ok;
	struct lock_queue_element *lockq;
	int pagesize;
	struct list_head partial_slabs;
	struct list_head full_slabs;
	pthread_t prune_thread;
};

struct lock {
	int type;
	off64_t start;
	off64_t end;
	pid_t pid;
	uint64_t owner;
	struct lock *next;
};

struct node {
	struct node *name_next;
	struct node *id_next;
	fuse_ino_t nodeid;
	unsigned int generation;
	int refctr;
	struct node *parent;
	char *name;
	uint64_t nlookup;
	int open_count;
	struct timespec stat_updated;
	struct timespec mtime;
	off64_t size;
	struct lock *locks;
	unsigned int is_hidden : 1;
	unsigned int cache_valid : 1;
	int treelock;
	char inline_name[32];
};

#define TREELOCK_WRITE -1
#define TREELOCK_WAIT_OFFSET INT_MIN

struct node_lru {
	struct node node;
	struct list_head lru;
	struct timespec forget_time;
};

struct fuse_dh {
	pthread_mutex_t lock;
	struct fuse *fuse;
	fuse_req_t req;
	char *contents;
	int allocated;
	unsigned len;
	unsigned size;
	unsigned needlen;
	int filled;
	uint64_t fh;
	int error;
	fuse_ino_t nodeid;
};

/* old dir handle */
struct fuse_dirhandle {
	fuse_fill_dir_t filler;
	void *buf;
};

struct fuse_context_i {
	struct fuse_context ctx;
	fuse_req_t req;
};

static pthread_key_t fuse_context_key;
static pthread_mutex_t fuse_context_lock = PTHREAD_MUTEX_INITIALIZER;
static int fuse_context_ref;
static struct fusemod_so *fuse_current_so;
static struct fuse_module *fuse_modules;

static int fuse_load_so_name(const char *soname)
{
	struct fusemod_so *so;

	so = calloc(1, sizeof(struct fusemod_so));
	if (!so) {
		fprintf(stderr, "fuse: memory allocation failed\n");
		return -1;
	}

	fuse_current_so = so;
	so->handle = dlopen(soname, RTLD_NOW);
	fuse_current_so = NULL;
	if (!so->handle) {
		fprintf(stderr, "fuse: %s\n", dlerror());
		goto err;
	}
	if (!so->ctr) {
		fprintf(stderr, "fuse: %s did not register any modules\n",
			soname);
		goto err;
	}
	return 0;

err:
	if (so->handle)
		dlclose(so->handle);
	free(so);
	return -1;
}

static int fuse_load_so_module(const char *module)
{
	int res;
	char *soname = malloc(strlen(module) + 64);
	if (!soname) {
		fprintf(stderr, "fuse: memory allocation failed\n");
		return -1;
	}
	sprintf(soname, "libfusemod_%s.so", module);
	res = fuse_load_so_name(soname);
	free(soname);
	return res;
}

static struct fuse_module *fuse_find_module(const char *module)
{
	struct fuse_module *m;
	for (m = fuse_modules; m; m = m->next) {
		if (strcmp(module, m->name) == 0) {
			m->ctr++;
			break;
		}
	}
	return m;
}

static struct fuse_module *fuse_get_module(const char *module)
{
	struct fuse_module *m;

	pthread_mutex_lock(&fuse_context_lock);
	m = fuse_find_module(module);
	if (!m) {
		int err = fuse_load_so_module(module);
		if (!err)
			m = fuse_find_module(module);
	}
	pthread_mutex_unlock(&fuse_context_lock);
	return m;
}

static void fuse_put_module(struct fuse_module *m)
{
	pthread_mutex_lock(&fuse_context_lock);
	assert(m->ctr > 0);
	m->ctr--;
	if (!m->ctr && m->so) {
		struct fusemod_so *so = m->so;
		assert(so->ctr > 0);
		so->ctr--;
		if (!so->ctr) {
			struct fuse_module **mp;
			for (mp = &fuse_modules; *mp;) {
				if ((*mp)->so == so)
					*mp = (*mp)->next;
				else
					mp = &(*mp)->next;
			}
			dlclose(so->handle);
			free(so);
		}
	}
	pthread_mutex_unlock(&fuse_context_lock);
}

static void init_list_head(struct list_head *list)
{
	list->next = list;
	list->prev = list;
}

static int list_empty(const struct list_head *head)
{
	return head->next == head;
}

static void list_add(struct list_head *new, struct list_head *prev,
		     struct list_head *next)
{
	next->prev = new;
	new->next = next;
	new->prev = prev;
	prev->next = new;
}

static inline void list_add_head(struct list_head *new, struct list_head *head)
{
	list_add(new, head, head->next);
}

static inline void list_add_tail(struct list_head *new, struct list_head *head)
{
	list_add(new, head->prev, head);
}

static inline void list_del(struct list_head *entry)
{
	struct list_head *prev = entry->prev;
	struct list_head *next = entry->next;

	next->prev = prev;
	prev->next = next;
}

static inline int lru_enabled(struct fuse *f)
{
	return f->conf.remember > 0;
}

static struct node_lru *node_lru(struct node *node)
{
	return (struct node_lru *) node;
}

static size_t get_node_size(struct fuse *f)
{
	if (lru_enabled(f))
		return sizeof(struct node_lru);
	else
		return sizeof(struct node);
}

#ifdef FUSE_NODE_SLAB
static struct node_slab *list_to_slab(struct list_head *head)
{
	return (struct node_slab *) head;
}

static struct node_slab *node_to_slab(struct fuse *f, struct node *node)
{
	return (struct node_slab *) (((uintptr_t) node) & ~((uintptr_t) f->pagesize - 1));
}

static int alloc_slab(struct fuse *f)
{
	void *mem;
	struct node_slab *slab;
	char *start;
	size_t num;
	size_t i;
	size_t node_size = get_node_size(f);

	mem = mmap(NULL, f->pagesize, PROT_READ | PROT_WRITE,
		   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);

	if (mem == MAP_FAILED)
		return -1;

	slab = mem;
	init_list_head(&slab->freelist);
	slab->used = 0;
	num = (f->pagesize - sizeof(struct node_slab)) / node_size;

	start = (char *) mem + f->pagesize - num * node_size;
	for (i = 0; i < num; i++) {
		struct list_head *n;

		n = (struct list_head *) (start + i * node_size);
		list_add_tail(n, &slab->freelist);
	}
	list_add_tail(&slab->list, &f->partial_slabs);

	return 0;
}

static struct node *alloc_node(struct fuse *f)
{
	struct node_slab *slab;
	struct list_head *node;

	if (list_empty(&f->partial_slabs)) {
		int res = alloc_slab(f);
		if (res != 0)
			return NULL;
	}
	slab = list_to_slab(f->partial_slabs.next);
	slab->used++;
	node = slab->freelist.next;
	list_del(node);
	if (list_empty(&slab->freelist)) {
		list_del(&slab->list);
		list_add_tail(&slab->list, &f->full_slabs);
	}
	memset(node, 0, sizeof(struct node));

	return (struct node *) node;
}

static void free_slab(struct fuse *f, struct node_slab *slab)
{
	int res;

	list_del(&slab->list);
	res = munmap(slab, f->pagesize);
	if (res == -1)
		fprintf(stderr, "fuse warning: munmap(%p) failed\n", slab);
}

static void free_node_mem(struct fuse *f, struct node *node)
{
	struct node_slab *slab = node_to_slab(f, node);
	struct list_head *n = (struct list_head *) node;

	slab->used--;
	if (slab->used) {
		if (list_empty(&slab->freelist)) {
			list_del(&slab->list);
			list_add_tail(&slab->list, &f->partial_slabs);
		}
		list_add_head(n, &slab->freelist);
	} else {
		free_slab(f, slab);
	}
}
#else
static struct node *alloc_node(struct fuse *f)
{
	return (struct node *) calloc(1, get_node_size(f));
}

static void free_node_mem(struct fuse *f, struct node *node)
{
	(void) f;
	free(node);
}
#endif

static size_t id_hash(struct fuse *f, fuse_ino_t ino)
{
	uint64_t hash = ((uint32_t) ino * 2654435761U) % f->id_table.size;
	uint64_t oldhash = hash % (f->id_table.size / 2);

	if (oldhash >= f->id_table.split)
		return oldhash;
	else
		return hash;
}

static struct node *get_node_nocheck(struct fuse *f, fuse_ino_t nodeid)
{
	size_t hash = id_hash(f, nodeid);
	struct node *node;

	for (node = f->id_table.array[hash]; node != NULL; node = node->id_next)
		if (node->nodeid == nodeid)
			return node;

	return NULL;
}

static struct node *get_node(struct fuse *f, fuse_ino_t nodeid)
{
	struct node *node = get_node_nocheck(f, nodeid);
	if (!node) {
		fprintf(stderr, "fuse internal error: node %llu not found\n",
			(unsigned long long) nodeid);
		abort();
	}
	return node;
}

static void curr_time(struct timespec *now);
static double diff_timespec(const struct timespec *t1,
			   const struct timespec *t2);

static void remove_node_lru(struct node *node)
{
	struct node_lru *lnode = node_lru(node);
	list_del(&lnode->lru);
	init_list_head(&lnode->lru);
}

static void set_forget_time(struct fuse *f, struct node *node)
{
	struct node_lru *lnode = node_lru(node);

	list_del(&lnode->lru);
	list_add_tail(&lnode->lru, &f->lru_table);
	curr_time(&lnode->forget_time);
}

static void free_node(struct fuse *f, struct node *node)
{
	if (node->name != node->inline_name)
		free(node->name);
	free_node_mem(f, node);
}

static void node_table_reduce(struct node_table *t)
{
	size_t newsize = t->size / 2;
	void *newarray;

	if (newsize < NODE_TABLE_MIN_SIZE)
		return;

	newarray = realloc(t->array, sizeof(struct node *) * newsize);
	if (newarray != NULL)
		t->array = newarray;

	t->size = newsize;
	t->split = t->size / 2;
}

static void remerge_id(struct fuse *f)
{
	struct node_table *t = &f->id_table;
	int iter;

	if (t->split == 0)
		node_table_reduce(t);

	for (iter = 8; t->split > 0 && iter; iter--) {
		struct node **upper;

		t->split--;
		upper = &t->array[t->split + t->size / 2];
		if (*upper) {
			struct node **nodep;

			for (nodep = &t->array[t->split]; *nodep;
			     nodep = &(*nodep)->id_next);

			*nodep = *upper;
			*upper = NULL;
			break;
		}
	}
}

static void unhash_id(struct fuse *f, struct node *node)
{
	struct node **nodep = &f->id_table.array[id_hash(f, node->nodeid)];

	for (; *nodep != NULL; nodep = &(*nodep)->id_next)
		if (*nodep == node) {
			*nodep = node->id_next;
			f->id_table.use--;

			if(f->id_table.use < f->id_table.size / 4)
				remerge_id(f);
			return;
		}
}

static int node_table_resize(struct node_table *t)
{
	size_t newsize = t->size * 2;
	void *newarray;

	newarray = realloc(t->array, sizeof(struct node *) * newsize);
	if (newarray == NULL)
		return -1;

	t->array = newarray;
	memset(t->array + t->size, 0, t->size * sizeof(struct node *));
	t->size = newsize;
	t->split = 0;

	return 0;
}

static void rehash_id(struct fuse *f)
{
	struct node_table *t = &f->id_table;
	struct node **nodep;
	struct node **next;
	size_t hash;

	if (t->split == t->size / 2)
		return;

	hash = t->split;
	t->split++;
	for (nodep = &t->array[hash]; *nodep != NULL; nodep = next) {
		struct node *node = *nodep;
		size_t newhash = id_hash(f, node->nodeid);

		if (newhash != hash) {
			next = nodep;
			*nodep = node->id_next;
			node->id_next = t->array[newhash];
			t->array[newhash] = node;
		} else {
			next = &node->id_next;
		}
	}
	if (t->split == t->size / 2)
		node_table_resize(t);
}

static void hash_id(struct fuse *f, struct node *node)
{
	size_t hash = id_hash(f, node->nodeid);
	node->id_next = f->id_table.array[hash];
	f->id_table.array[hash] = node;
	f->id_table.use++;

	if (f->id_table.use >= f->id_table.size / 2)
		rehash_id(f);
}

static size_t name_hash(struct fuse *f, fuse_ino_t parent,
			const char *name)
{
	uint64_t hash = parent;
	uint64_t oldhash;

	for (; *name; name++)
		hash = hash * 31 + (unsigned char) *name;

	hash %= f->name_table.size;
	oldhash = hash % (f->name_table.size / 2);
	if (oldhash >= f->name_table.split)
		return oldhash;
	else
		return hash;
}

static void unref_node(struct fuse *f, struct node *node);

static void remerge_name(struct fuse *f)
{
	struct node_table *t = &f->name_table;
	int iter;

	if (t->split == 0)
		node_table_reduce(t);

	for (iter = 8; t->split > 0 && iter; iter--) {
		struct node **upper;

		t->split--;
		upper = &t->array[t->split + t->size / 2];
		if (*upper) {
			struct node **nodep;

			for (nodep = &t->array[t->split]; *nodep;
			     nodep = &(*nodep)->name_next);

			*nodep = *upper;
			*upper = NULL;
			break;
		}
	}
}

static void unhash_name(struct fuse *f, struct node *node)
{
	if (node->name) {
		size_t hash = name_hash(f, node->parent->nodeid, node->name);
		struct node **nodep = &f->name_table.array[hash];

		for (; *nodep != NULL; nodep = &(*nodep)->name_next)
			if (*nodep == node) {
				*nodep = node->name_next;
				node->name_next = NULL;
				unref_node(f, node->parent);
				if (node->name != node->inline_name)
					free(node->name);
				node->name = NULL;
				node->parent = NULL;
				f->name_table.use--;

				if (f->name_table.use < f->name_table.size / 4)
					remerge_name(f);
				return;
			}
		fprintf(stderr,
			"fuse internal error: unable to unhash node: %llu\n",
			(unsigned long long) node->nodeid);
		abort();
	}
}

static void rehash_name(struct fuse *f)
{
	struct node_table *t = &f->name_table;
	struct node **nodep;
	struct node **next;
	size_t hash;

	if (t->split == t->size / 2)
		return;

	hash = t->split;
	t->split++;
	for (nodep = &t->array[hash]; *nodep != NULL; nodep = next) {
		struct node *node = *nodep;
		size_t newhash = name_hash(f, node->parent->nodeid, node->name);

		if (newhash != hash) {
			next = nodep;
			*nodep = node->name_next;
			node->name_next = t->array[newhash];
			t->array[newhash] = node;
		} else {
			next = &node->name_next;
		}
	}
	if (t->split == t->size / 2)
		node_table_resize(t);
}

static int hash_name(struct fuse *f, struct node *node, fuse_ino_t parentid,
		     const char *name)
{
	size_t hash = name_hash(f, parentid, name);
	struct node *parent = get_node(f, parentid);
	if (strlen(name) < sizeof(node->inline_name)) {
		strcpy(node->inline_name, name);
		node->name = node->inline_name;
	} else {
		node->name = strdup(name);
		if (node->name == NULL)
			return -1;
	}

	parent->refctr ++;
	node->parent = parent;
	node->name_next = f->name_table.array[hash];
	f->name_table.array[hash] = node;
	f->name_table.use++;

	if (f->name_table.use >= f->name_table.size / 2)
		rehash_name(f);

	return 0;
}

static void delete_node(struct fuse *f, struct node *node)
{
	if (f->conf.debug)
		fprintf(stderr, "DELETE: %llu\n",
			(unsigned long long) node->nodeid);

	assert(node->treelock == 0);
	unhash_name(f, node);
	if (lru_enabled(f))
		remove_node_lru(node);
	unhash_id(f, node);
	free_node(f, node);
}

static void unref_node(struct fuse *f, struct node *node)
{
	assert(node->refctr > 0);
	node->refctr --;
	if (!node->refctr)
		delete_node(f, node);
}

static fuse_ino_t next_id(struct fuse *f)
{
	do {
		f->ctr = (f->ctr + 1) & 0xffffffff;
		if (!f->ctr)
			f->generation ++;
	} while (f->ctr == 0 || f->ctr == FUSE_UNKNOWN_INO ||
		 get_node_nocheck(f, f->ctr) != NULL);
	return f->ctr;
}

static struct node *lookup_node(struct fuse *f, fuse_ino_t parent,
				const char *name)
{
	size_t hash = name_hash(f, parent, name);
	struct node *node;

	for (node = f->name_table.array[hash]; node != NULL; node = node->name_next)
		if (node->parent->nodeid == parent &&
		    strcmp(node->name, name) == 0)
			return node;

	return NULL;
}

static void inc_nlookup(struct node *node)
{
	if (!node->nlookup)
		node->refctr++;
	node->nlookup++;
}

static struct node *find_node(struct fuse *f, fuse_ino_t parent,
			      const char *name)
{
	struct node *node;

	pthread_mutex_lock(&f->lock);
	if (!name)
		node = get_node(f, parent);
	else
		node = lookup_node(f, parent, name);
	if (node == NULL) {
		node = alloc_node(f);
		if (node == NULL)
			goto out_err;

		node->nodeid = next_id(f);
		node->generation = f->generation;
		if (f->conf.remember)
			inc_nlookup(node);

		if (hash_name(f, node, parent, name) == -1) {
			free_node(f, node);
			node = NULL;
			goto out_err;
		}
		hash_id(f, node);
		if (lru_enabled(f)) {
			struct node_lru *lnode = node_lru(node);
			init_list_head(&lnode->lru);
		}
	} else if (lru_enabled(f) && node->nlookup == 1) {
		remove_node_lru(node);
	}
	inc_nlookup(node);
out_err:
	pthread_mutex_unlock(&f->lock);
	return node;
}

static char *add_name(char **buf, unsigned *bufsize, char *s, const char *name)
{
	size_t len = strlen(name);

	if (s - len <= *buf) {
		unsigned pathlen = *bufsize - (s - *buf);
		unsigned newbufsize = *bufsize;
		char *newbuf;

		while (newbufsize < pathlen + len + 1) {
			if (newbufsize >= 0x80000000)
				newbufsize = 0xffffffff;
			else
				newbufsize *= 2;
		}

		newbuf = realloc(*buf, newbufsize);
		if (newbuf == NULL)
			return NULL;

		*buf = newbuf;
		s = newbuf + newbufsize - pathlen;
		memmove(s, newbuf + *bufsize - pathlen, pathlen);
		*bufsize = newbufsize;
	}
	s -= len;
	strncpy(s, name, len);
	s--;
	*s = '/';

	return s;
}

static void unlock_path(struct fuse *f, fuse_ino_t nodeid, struct node *wnode,
			struct node *end)
{
	struct node *node;

	if (wnode) {
		assert(wnode->treelock == TREELOCK_WRITE);
		wnode->treelock = 0;
	}

	for (node = get_node(f, nodeid);
	     node != end && node->nodeid != FUSE_ROOT_ID; node = node->parent) {
		assert(node->treelock != 0);
		assert(node->treelock != TREELOCK_WAIT_OFFSET);
		assert(node->treelock != TREELOCK_WRITE);
		node->treelock--;
		if (node->treelock == TREELOCK_WAIT_OFFSET)
			node->treelock = 0;
	}
}

static int try_get_path(struct fuse *f, fuse_ino_t nodeid, const char *name,
			char **path, struct node **wnodep, bool need_lock)
{
	unsigned bufsize = 256;
	char *buf;
	char *s;
	struct node *node;
	struct node *wnode = NULL;
	int err;

	*path = NULL;

	err = -ENOMEM;
	buf = malloc(bufsize);
	if (buf == NULL)
		goto out_err;

	s = buf + bufsize - 1;
	*s = '\0';

	if (name != NULL) {
		s = add_name(&buf, &bufsize, s, name);
		err = -ENOMEM;
		if (s == NULL)
			goto out_free;
	}

	if (wnodep) {
		assert(need_lock);
		wnode = lookup_node(f, nodeid, name);
		if (wnode) {
			if (wnode->treelock != 0) {
				if (wnode->treelock > 0)
					wnode->treelock += TREELOCK_WAIT_OFFSET;
				err = -EAGAIN;
				goto out_free;
			}
			wnode->treelock = TREELOCK_WRITE;
		}
	}

	for (node = get_node(f, nodeid); node->nodeid != FUSE_ROOT_ID;
	     node = node->parent) {
		err = -ENOENT;
		if (node->name == NULL || node->parent == NULL)
			goto out_unlock;

		err = -ENOMEM;
		s = add_name(&buf, &bufsize, s, node->name);
		if (s == NULL)
			goto out_unlock;

		if (need_lock) {
			err = -EAGAIN;
			if (node->treelock < 0)
				goto out_unlock;

			node->treelock++;
		}
	}

	if (s[0])
		memmove(buf, s, bufsize - (s - buf));
	else
		strcpy(buf, "/");

	*path = buf;
	if (wnodep)
		*wnodep = wnode;

	return 0;

 out_unlock:
	if (need_lock)
		unlock_path(f, nodeid, wnode, node);
 out_free:
	free(buf);

 out_err:
	return err;
}

static void queue_element_unlock(struct fuse *f, struct lock_queue_element *qe)
{
	struct node *wnode;

	if (qe->first_locked) {
		wnode = qe->wnode1 ? *qe->wnode1 : NULL;
		unlock_path(f, qe->nodeid1, wnode, NULL);
	}
	if (qe->second_locked) {
		wnode = qe->wnode2 ? *qe->wnode2 : NULL;
		unlock_path(f, qe->nodeid2, wnode, NULL);
	}
}

static void queue_element_wakeup(struct fuse *f, struct lock_queue_element *qe)
{
	int err;
	bool first = (qe == f->lockq);

	if (!qe->path1) {
		/* Just waiting for it to be unlocked */
		if (get_node(f, qe->nodeid1)->treelock == 0)
			pthread_cond_signal(&qe->cond);

		return;
	}

	if (!qe->first_locked) {
		err = try_get_path(f, qe->nodeid1, qe->name1, qe->path1,
				   qe->wnode1, true);
		if (!err)
			qe->first_locked = true;
		else if (err != -EAGAIN)
			goto err_unlock;
	}
	if (!qe->second_locked && qe->path2) {
		err = try_get_path(f, qe->nodeid2, qe->name2, qe->path2,
				   qe->wnode2, true);
		if (!err)
			qe->second_locked = true;
		else if (err != -EAGAIN)
			goto err_unlock;
	}

	if (qe->first_locked && (qe->second_locked || !qe->path2)) {
		err = 0;
		goto done;
	}

	/*
	 * Only let the first element be partially locked otherwise there could
	 * be a deadlock.
	 *
	 * But do allow the first element to be partially locked to prevent
	 * starvation.
	 */
	if (!first)
		queue_element_unlock(f, qe);

	/* keep trying */
	return;

err_unlock:
	queue_element_unlock(f, qe);
done:
	qe->err = err;
	qe->done = true;
	pthread_cond_signal(&qe->cond);
}

static void wake_up_queued(struct fuse *f)
{
	struct lock_queue_element *qe;

	for (qe = f->lockq; qe != NULL; qe = qe->next)
		queue_element_wakeup(f, qe);
}

static void debug_path(struct fuse *f, const char *msg, fuse_ino_t nodeid,
		       const char *name, bool wr)
{
	if (f->conf.debug) {
		struct node *wnode = NULL;

		if (wr)
			wnode = lookup_node(f, nodeid, name);

		if (wnode)
			fprintf(stderr, "%s %li (w)\n",	msg, wnode->nodeid);
		else
			fprintf(stderr, "%s %li\n", msg, nodeid);
	}
}

static void queue_path(struct fuse *f, struct lock_queue_element *qe)
{
	struct lock_queue_element **qp;

	qe->done = false;
	qe->first_locked = false;
	qe->second_locked = false;
	pthread_cond_init(&qe->cond, NULL);
	qe->next = NULL;
	for (qp = &f->lockq; *qp != NULL; qp = &(*qp)->next);
	*qp = qe;
}

static void dequeue_path(struct fuse *f, struct lock_queue_element *qe)
{
	struct lock_queue_element **qp;

	pthread_cond_destroy(&qe->cond);
	for (qp = &f->lockq; *qp != qe; qp = &(*qp)->next);
	*qp = qe->next;
}

static int wait_path(struct fuse *f, struct lock_queue_element *qe)
{
	queue_path(f, qe);

	do {
		pthread_cond_wait(&qe->cond, &f->lock);
	} while (!qe->done);

	dequeue_path(f, qe);

	return qe->err;
}

static int get_path_common(struct fuse *f, fuse_ino_t nodeid, const char *name,
			   char **path, struct node **wnode)
{
	int err;

	pthread_mutex_lock(&f->lock);
	err = try_get_path(f, nodeid, name, path, wnode, true);
	if (err == -EAGAIN) {
		struct lock_queue_element qe = {
			.nodeid1 = nodeid,
			.name1 = name,
			.path1 = path,
			.wnode1 = wnode,
		};
		debug_path(f, "QUEUE PATH", nodeid, name, !!wnode);
		err = wait_path(f, &qe);
		debug_path(f, "DEQUEUE PATH", nodeid, name, !!wnode);
	}
	pthread_mutex_unlock(&f->lock);

	return err;
}

static int get_path(struct fuse *f, fuse_ino_t nodeid, char **path)
{
	return get_path_common(f, nodeid, NULL, path, NULL);
}

static int get_path_nullok(struct fuse *f, fuse_ino_t nodeid, char **path)
{
	int err = 0;

	if (f->conf.nopath) {
		*path = NULL;
	} else {
		err = get_path_common(f, nodeid, NULL, path, NULL);
		if (err == -ENOENT && f->nullpath_ok)
			err = 0;
	}

	return err;
}

static int get_path_name(struct fuse *f, fuse_ino_t nodeid, const char *name,
			 char **path)
{
	return get_path_common(f, nodeid, name, path, NULL);
}

static int get_path_wrlock(struct fuse *f, fuse_ino_t nodeid, const char *name,
			   char **path, struct node **wnode)
{
	return get_path_common(f, nodeid, name, path, wnode);
}

static int try_get_path2(struct fuse *f, fuse_ino_t nodeid1, const char *name1,
			 fuse_ino_t nodeid2, const char *name2,
			 char **path1, char **path2,
			 struct node **wnode1, struct node **wnode2)
{
	int err;

	/* FIXME: locking two paths needs deadlock checking */
	err = try_get_path(f, nodeid1, name1, path1, wnode1, true);
	if (!err) {
		err = try_get_path(f, nodeid2, name2, path2, wnode2, true);
		if (err) {
			struct node *wn1 = wnode1 ? *wnode1 : NULL;

			unlock_path(f, nodeid1, wn1, NULL);
			free(*path1);
		}
	}
	return err;
}

static int get_path2(struct fuse *f, fuse_ino_t nodeid1, const char *name1,
		     fuse_ino_t nodeid2, const char *name2,
		     char **path1, char **path2,
		     struct node **wnode1, struct node **wnode2)
{
	int err;

	pthread_mutex_lock(&f->lock);
	err = try_get_path2(f, nodeid1, name1, nodeid2, name2,
			    path1, path2, wnode1, wnode2);
	if (err == -EAGAIN) {
		struct lock_queue_element qe = {
			.nodeid1 = nodeid1,
			.name1 = name1,
			.path1 = path1,
			.wnode1 = wnode1,
			.nodeid2 = nodeid2,
			.name2 = name2,
			.path2 = path2,
			.wnode2 = wnode2,
		};

		debug_path(f, "QUEUE PATH1", nodeid1, name1, !!wnode1);
		debug_path(f, "      PATH2", nodeid2, name2, !!wnode2);
		err = wait_path(f, &qe);
		debug_path(f, "DEQUEUE PATH1", nodeid1, name1, !!wnode1);
		debug_path(f, "        PATH2", nodeid2, name2, !!wnode2);
	}
	pthread_mutex_unlock(&f->lock);

	return err;
}

static void free_path_wrlock(struct fuse *f, fuse_ino_t nodeid,
			     struct node *wnode, char *path)
{
	pthread_mutex_lock(&f->lock);
	unlock_path(f, nodeid, wnode, NULL);
	if (f->lockq)
		wake_up_queued(f);
	pthread_mutex_unlock(&f->lock);
	free(path);
}

static void free_path(struct fuse *f, fuse_ino_t nodeid, char *path)
{
	if (path)
		free_path_wrlock(f, nodeid, NULL, path);
}

static void free_path2(struct fuse *f, fuse_ino_t nodeid1, fuse_ino_t nodeid2,
		       struct node *wnode1, struct node *wnode2,
		       char *path1, char *path2)
{
	pthread_mutex_lock(&f->lock);
	unlock_path(f, nodeid1, wnode1, NULL);
	unlock_path(f, nodeid2, wnode2, NULL);
	wake_up_queued(f);
	pthread_mutex_unlock(&f->lock);
	free(path1);
	free(path2);
}

static void forget_node(struct fuse *f, fuse_ino_t nodeid, uint64_t nlookup)
{
	struct node *node;
	if (nodeid == FUSE_ROOT_ID)
		return;
	pthread_mutex_lock(&f->lock);
	node = get_node(f, nodeid);

	/*
	 * Node may still be locked due to interrupt idiocy in open,
	 * create and opendir
	 */
	while (node->nlookup == nlookup && node->treelock) {
		struct lock_queue_element qe = {
			.nodeid1 = nodeid,
		};

		debug_path(f, "QUEUE PATH (forget)", nodeid, NULL, false);
		queue_path(f, &qe);

		do {
			pthread_cond_wait(&qe.cond, &f->lock);
		} while (node->nlookup == nlookup && node->treelock);

		dequeue_path(f, &qe);
		debug_path(f, "DEQUEUE_PATH (forget)", nodeid, NULL, false);
	}

	assert(node->nlookup >= nlookup);
	node->nlookup -= nlookup;
	if (!node->nlookup) {
		unref_node(f, node);
	} else if (lru_enabled(f) && node->nlookup == 1) {
		set_forget_time(f, node);
	}
	pthread_mutex_unlock(&f->lock);
}

static void unlink_node(struct fuse *f, struct node *node)
{
	if (f->conf.remember) {
		assert(node->nlookup > 1);
		node->nlookup--;
	}
	unhash_name(f, node);
}

static void remove_node(struct fuse *f, fuse_ino_t dir, const char *name)
{
	struct node *node;

	pthread_mutex_lock(&f->lock);
	node = lookup_node(f, dir, name);
	if (node != NULL)
		unlink_node(f, node);
	pthread_mutex_unlock(&f->lock);
}

static int rename_node(struct fuse *f, fuse_ino_t olddir, const char *oldname,
		       fuse_ino_t newdir, const char *newname, int hide)
{
	struct node *node;
	struct node *newnode;
	int err = 0;

	pthread_mutex_lock(&f->lock);
	node  = lookup_node(f, olddir, oldname);
	newnode	 = lookup_node(f, newdir, newname);
	if (node == NULL)
		goto out;

	if (newnode != NULL) {
		if (hide) {
			fprintf(stderr, "fuse: hidden file got created during hiding\n");
			err = -EBUSY;
			goto out;
		}
		unlink_node(f, newnode);
	}

	unhash_name(f, node);
	if (hash_name(f, node, newdir, newname) == -1) {
		err = -ENOMEM;
		goto out;
	}

	if (hide)
		node->is_hidden = 1;

out:
	pthread_mutex_unlock(&f->lock);
	return err;
}

static void set_stat(struct fuse *f, fuse_ino_t nodeid, struct stat *stbuf)
{
	if (!f->conf.use_ino)
		stbuf->st_ino = nodeid;
	if (f->conf.set_mode)
		stbuf->st_mode = (stbuf->st_mode & S_IFMT) |
				 (0777 & ~f->conf.umask);
	if (f->conf.set_uid)
		stbuf->st_uid = f->conf.uid;
	if (f->conf.set_gid)
		stbuf->st_gid = f->conf.gid;
}

static struct fuse *req_fuse(fuse_req_t req)
{
	return (struct fuse *) fuse_req_userdata(req);
}

static void fuse_intr_sighandler(int sig)
{
	(void) sig;
	/* Nothing to do */
}

struct fuse_intr_data {
	pthread_t id;
	pthread_cond_t cond;
	int finished;
};

static void fuse_interrupt(fuse_req_t req, void *d_)
{
	struct fuse_intr_data *d = d_;
	struct fuse *f = req_fuse(req);

	if (d->id == pthread_self())
		return;

	pthread_mutex_lock(&f->lock);
	while (!d->finished) {
		struct timeval now;
		struct timespec timeout;

		pthread_kill(d->id, f->conf.intr_signal);
		gettimeofday(&now, NULL);
		timeout.tv_sec = now.tv_sec + 1;
		timeout.tv_nsec = now.tv_usec * 1000;
		pthread_cond_timedwait(&d->cond, &f->lock, &timeout);
	}
	pthread_mutex_unlock(&f->lock);
}

static void fuse_do_finish_interrupt(struct fuse *f, fuse_req_t req,
				     struct fuse_intr_data *d)
{
	pthread_mutex_lock(&f->lock);
	d->finished = 1;
	pthread_cond_broadcast(&d->cond);
	pthread_mutex_unlock(&f->lock);
	fuse_req_interrupt_func(req, NULL, NULL);
	pthread_cond_destroy(&d->cond);
}

static void fuse_do_prepare_interrupt(fuse_req_t req, struct fuse_intr_data *d)
{
	d->id = pthread_self();
	pthread_cond_init(&d->cond, NULL);
	d->finished = 0;
	fuse_req_interrupt_func(req, fuse_interrupt, d);
}

static inline void fuse_finish_interrupt(struct fuse *f, fuse_req_t req,
					 struct fuse_intr_data *d)
{
	if (f->conf.intr)
		fuse_do_finish_interrupt(f, req, d);
}

static inline void fuse_prepare_interrupt(struct fuse *f, fuse_req_t req,
					  struct fuse_intr_data *d)
{
	if (f->conf.intr)
		fuse_do_prepare_interrupt(req, d);
}

#if !defined(__FreeBSD__) && !defined(__NetBSD__)

static int fuse_compat_open(struct fuse_fs *fs, const char *path,
			    struct fuse_file_info *fi)
{
	int err;
	if (!fs->compat || fs->compat >= 25)
		err = fs->op.open(path, fi);
	else if (fs->compat == 22) {
		struct fuse_file_info_compat tmp;
		memcpy(&tmp, fi, sizeof(tmp));
		err = ((struct fuse_operations_compat22 *) &fs->op)->open(path,
									  &tmp);
		memcpy(fi, &tmp, sizeof(tmp));
		fi->fh = tmp.fh;
	} else
		err = ((struct fuse_operations_compat2 *) &fs->op)
			->open(path, fi->flags);
	return err;
}

static int fuse_compat_release(struct fuse_fs *fs, const char *path,
			       struct fuse_file_info *fi)
{
	if (!fs->compat || fs->compat >= 22)
		return fs->op.release(path, fi);
	else
		return ((struct fuse_operations_compat2 *) &fs->op)
			->release(path, fi->flags);
}

static int fuse_compat_opendir(struct fuse_fs *fs, const char *path,
			       struct fuse_file_info *fi)
{
	if (!fs->compat || fs->compat >= 25)
		return fs->op.opendir(path, fi);
	else {
		int err;
		struct fuse_file_info_compat tmp;
		memcpy(&tmp, fi, sizeof(tmp));
		err = ((struct fuse_operations_compat22 *) &fs->op)
			->opendir(path, &tmp);
		memcpy(fi, &tmp, sizeof(tmp));
		fi->fh = tmp.fh;
		return err;
	}
}

static void convert_statfs_compat(struct fuse_statfs_compat1 *compatbuf,
				  struct statvfs *stbuf)
{
	stbuf->f_bsize	 = compatbuf->block_size;
	stbuf->f_blocks	 = compatbuf->blocks;
	stbuf->f_bfree	 = compatbuf->blocks_free;
	stbuf->f_bavail	 = compatbuf->blocks_free;
	stbuf->f_files	 = compatbuf->files;
	stbuf->f_ffree	 = compatbuf->files_free;
	stbuf->f_namemax = compatbuf->namelen;
}

static void convert_statfs_old(struct statfs *oldbuf, struct statvfs *stbuf)
{
	stbuf->f_bsize	 = oldbuf->f_bsize;
	stbuf->f_blocks	 = oldbuf->f_blocks;
	stbuf->f_bfree	 = oldbuf->f_bfree;
	stbuf->f_bavail	 = oldbuf->f_bavail;
	stbuf->f_files	 = oldbuf->f_files;
	stbuf->f_ffree	 = oldbuf->f_ffree;
	stbuf->f_namemax = oldbuf->f_namelen;
}

static int fuse_compat_statfs(struct fuse_fs *fs, const char *path,
			      struct statvfs *buf)
{
	int err;

	if (!fs->compat || fs->compat >= 25) {
		err = fs->op.statfs(fs->compat == 25 ? "/" : path, buf);
	} else if (fs->compat > 11) {
		struct statfs oldbuf;
		err = ((struct fuse_operations_compat22 *) &fs->op)
			->statfs("/", &oldbuf);
		if (!err)
			convert_statfs_old(&oldbuf, buf);
	} else {
		struct fuse_statfs_compat1 compatbuf;
		memset(&compatbuf, 0, sizeof(struct fuse_statfs_compat1));
		err = ((struct fuse_operations_compat1 *) &fs->op)
			->statfs(&compatbuf);
		if (!err)
			convert_statfs_compat(&compatbuf, buf);
	}
	return err;
}

#else /* __FreeBSD__ || __NetBSD__ */

static inline int fuse_compat_open(struct fuse_fs *fs, char *path,
				   struct fuse_file_info *fi)
{
	return fs->op.open(path, fi);
}

static inline int fuse_compat_release(struct fuse_fs *fs, const char *path,
				      struct fuse_file_info *fi)
{
	return fs->op.release(path, fi);
}

static inline int fuse_compat_opendir(struct fuse_fs *fs, const char *path,
				      struct fuse_file_info *fi)
{
	return fs->op.opendir(path, fi);
}

static inline int fuse_compat_statfs(struct fuse_fs *fs, const char *path,
				     struct statvfs *buf)
{
	return fs->op.statfs(fs->compat == 25 ? "/" : path, buf);
}

#endif /* __FreeBSD__ || __NetBSD__ */

int fuse_fs_getattr(struct fuse_fs *fs, const char *path, struct stat *buf)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.getattr) {
		if (fs->debug)
			fprintf(stderr, "getattr %s\n", path);

		return fs->op.getattr(path, buf);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_fgetattr(struct fuse_fs *fs, const char *path, struct stat *buf,
		     struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.fgetattr) {
		if (fs->debug)
			fprintf(stderr, "fgetattr[%llu] %s\n",
				(unsigned long long) fi->fh, path);

		return fs->op.fgetattr(path, buf, fi);
	} else if (path && fs->op.getattr) {
		if (fs->debug)
			fprintf(stderr, "getattr %s\n", path);

		return fs->op.getattr(path, buf);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_rename(struct fuse_fs *fs, const char *oldpath,
		   const char *newpath)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.rename) {
		if (fs->debug)
			fprintf(stderr, "rename %s %s\n", oldpath, newpath);

		return fs->op.rename(oldpath, newpath);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_unlink(struct fuse_fs *fs, const char *path)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.unlink) {
		if (fs->debug)
			fprintf(stderr, "unlink %s\n", path);

		return fs->op.unlink(path);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_rmdir(struct fuse_fs *fs, const char *path)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.rmdir) {
		if (fs->debug)
			fprintf(stderr, "rmdir %s\n", path);

		return fs->op.rmdir(path);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_symlink(struct fuse_fs *fs, const char *linkname, const char *path)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.symlink) {
		if (fs->debug)
			fprintf(stderr, "symlink %s %s\n", linkname, path);

		return fs->op.symlink(linkname, path);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_link(struct fuse_fs *fs, const char *oldpath, const char *newpath)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.link) {
		if (fs->debug)
			fprintf(stderr, "link %s %s\n", oldpath, newpath);

		return fs->op.link(oldpath, newpath);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_release(struct fuse_fs *fs,	 const char *path,
		    struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.release) {
		if (fs->debug)
			fprintf(stderr, "release%s[%llu] flags: 0x%x\n",
				fi->flush ? "+flush" : "",
				(unsigned long long) fi->fh, fi->flags);

		return fuse_compat_release(fs, path, fi);
	} else {
		return 0;
	}
}

int fuse_fs_opendir(struct fuse_fs *fs, const char *path,
		    struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.opendir) {
		int err;

		if (fs->debug)
			fprintf(stderr, "opendir flags: 0x%x %s\n", fi->flags,
				path);

		err = fuse_compat_opendir(fs, path, fi);

		if (fs->debug && !err)
			fprintf(stderr, "   opendir[%lli] flags: 0x%x %s\n",
				(unsigned long long) fi->fh, fi->flags, path);

		return err;
	} else {
		return 0;
	}
}

int fuse_fs_open(struct fuse_fs *fs, const char *path,
		 struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.open) {
		int err;

		if (fs->debug)
			fprintf(stderr, "open flags: 0x%x %s\n", fi->flags,
				path);

		err = fuse_compat_open(fs, path, fi);

		if (fs->debug && !err)
			fprintf(stderr, "   open[%lli] flags: 0x%x %s\n",
				(unsigned long long) fi->fh, fi->flags, path);

		return err;
	} else {
		return 0;
	}
}

static void fuse_free_buf(struct fuse_bufvec *buf)
{
	if (buf != NULL) {
		size_t i;

		for (i = 0; i < buf->count; i++)
			free(buf->buf[i].mem);
		free(buf);
	}
}

int fuse_fs_read_buf(struct fuse_fs *fs, const char *path,
		     struct fuse_bufvec **bufp, size_t size, off64_t off,
		     struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.read || fs->op.read_buf) {
		int res;

		if (fs->debug)
			fprintf(stderr,
				"read[%llu] %zu bytes from %llu flags: 0x%x\n",
				(unsigned long long) fi->fh,
				size, (unsigned long long) off, fi->flags);

		if (fs->op.read_buf) {
			res = fs->op.read_buf(path, bufp, size, off, fi);
		} else {
			struct fuse_bufvec *buf;
			void *mem;

			buf = malloc(sizeof(struct fuse_bufvec));
			if (buf == NULL)
				return -ENOMEM;

			mem = malloc(size);
			if (mem == NULL) {
				free(buf);
				return -ENOMEM;
			}
			*buf = FUSE_BUFVEC_INIT(size);
			buf->buf[0].mem = mem;
			*bufp = buf;

			res = fs->op.read(path, mem, size, off, fi);
			if (res >= 0)
				buf->buf[0].size = res;
		}

		if (fs->debug && res >= 0)
			fprintf(stderr, "   read[%llu] %zu bytes from %llu\n",
				(unsigned long long) fi->fh,
				fuse_buf_size(*bufp),
				(unsigned long long) off);
		if (res >= 0 && fuse_buf_size(*bufp) > (int) size)
			fprintf(stderr, "fuse: read too many bytes\n");

		if (res < 0)
			return res;

		return 0;
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_read(struct fuse_fs *fs, const char *path, char *mem, size_t size,
		 off64_t off, struct fuse_file_info *fi)
{
	int res;
	struct fuse_bufvec *buf = NULL;

	res = fuse_fs_read_buf(fs, path, &buf, size, off, fi);
	if (res == 0) {
		struct fuse_bufvec dst = FUSE_BUFVEC_INIT(size);

		dst.buf[0].mem = mem;
		res = fuse_buf_copy(&dst, buf, 0);
	}
	fuse_free_buf(buf);

	return res;
}

int fuse_fs_write_buf(struct fuse_fs *fs, const char *path,
		      struct fuse_bufvec *buf, off64_t off,
		      struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.write_buf || fs->op.write) {
		int res;
		size_t size = fuse_buf_size(buf);

		assert(buf->idx == 0 && buf->off == 0);
		if (fs->debug)
			fprintf(stderr,
				"write%s[%llu] %zu bytes to %llu flags: 0x%x\n",
				fi->writepage ? "page" : "",
				(unsigned long long) fi->fh,
				size,
				(unsigned long long) off,
				fi->flags);

		if (fs->op.write_buf) {
			res = fs->op.write_buf(path, buf, off, fi);
		} else {
			void *mem = NULL;
			struct fuse_buf *flatbuf;
			struct fuse_bufvec tmp = FUSE_BUFVEC_INIT(size);

			if (buf->count == 1 &&
			    !(buf->buf[0].flags & FUSE_BUF_IS_FD)) {
				flatbuf = &buf->buf[0];
			} else {
				res = -ENOMEM;
				mem = malloc(size);
				if (mem == NULL)
					goto out;

				tmp.buf[0].mem = mem;
				res = fuse_buf_copy(&tmp, buf, 0);
				if (res <= 0)
					goto out_free;

				tmp.buf[0].size = res;
				flatbuf = &tmp.buf[0];
			}

			res = fs->op.write(path, flatbuf->mem, flatbuf->size,
					   off, fi);
out_free:
			free(mem);
		}
out:
		if (fs->debug && res >= 0)
			fprintf(stderr, "   write%s[%llu] %u bytes to %llu\n",
				fi->writepage ? "page" : "",
				(unsigned long long) fi->fh, res,
				(unsigned long long) off);
		if (res > (int) size)
			fprintf(stderr, "fuse: wrote too many bytes\n");

		return res;
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_write(struct fuse_fs *fs, const char *path, const char *mem,
		  size_t size, off64_t off, struct fuse_file_info *fi)
{
	struct fuse_bufvec bufv = FUSE_BUFVEC_INIT(size);

	bufv.buf[0].mem = (void *) mem;

	return fuse_fs_write_buf(fs, path, &bufv, off, fi);
}

int fuse_fs_fsync(struct fuse_fs *fs, const char *path, int datasync,
		  struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.fsync) {
		if (fs->debug)
			fprintf(stderr, "fsync[%llu] datasync: %i\n",
				(unsigned long long) fi->fh, datasync);

		return fs->op.fsync(path, datasync, fi);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_fsyncdir(struct fuse_fs *fs, const char *path, int datasync,
		     struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.fsyncdir) {
		if (fs->debug)
			fprintf(stderr, "fsyncdir[%llu] datasync: %i\n",
				(unsigned long long) fi->fh, datasync);

		return fs->op.fsyncdir(path, datasync, fi);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_flush(struct fuse_fs *fs, const char *path,
		  struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.flush) {
		if (fs->debug)
			fprintf(stderr, "flush[%llu]\n",
				(unsigned long long) fi->fh);

		return fs->op.flush(path, fi);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_statfs(struct fuse_fs *fs, const char *path, struct statvfs *buf)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.statfs) {
		if (fs->debug)
			fprintf(stderr, "statfs %s\n", path);

		return fuse_compat_statfs(fs, path, buf);
	} else {
		buf->f_namemax = 255;
		buf->f_bsize = 512;
		return 0;
	}
}

int fuse_fs_releasedir(struct fuse_fs *fs, const char *path,
		       struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.releasedir) {
		if (fs->debug)
			fprintf(stderr, "releasedir[%llu] flags: 0x%x\n",
				(unsigned long long) fi->fh, fi->flags);

		return fs->op.releasedir(path, fi);
	} else {
		return 0;
	}
}

static int fill_dir_old(struct fuse_dirhandle *dh, const char *name, int type,
			ino_t ino)
{
	int res;
	struct stat stbuf;

	memset(&stbuf, 0, sizeof(stbuf));
	stbuf.st_mode = type << 12;
	stbuf.st_ino = ino;

	res = dh->filler(dh->buf, name, &stbuf, 0);
	return res ? -ENOMEM : 0;
}

int fuse_fs_readdir(struct fuse_fs *fs, const char *path, void *buf,
		    fuse_fill_dir_t filler, off64_t off,
		    struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.readdir) {
		if (fs->debug)
			fprintf(stderr, "readdir[%llu] from %llu\n",
				(unsigned long long) fi->fh,
				(unsigned long long) off);

		return fs->op.readdir(path, buf, filler, off, fi);
	} else if (fs->op.getdir) {
		struct fuse_dirhandle dh;

		if (fs->debug)
			fprintf(stderr, "getdir[%llu]\n",
				(unsigned long long) fi->fh);

		dh.filler = filler;
		dh.buf = buf;
		return fs->op.getdir(path, &dh, fill_dir_old);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_create(struct fuse_fs *fs, const char *path, mode_t mode,
		   struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.create) {
		int err;

		if (fs->debug)
			fprintf(stderr,
				"create flags: 0x%x %s 0%o umask=0%03o\n",
				fi->flags, path, mode,
				fuse_get_context()->umask);

		err = fs->op.create(path, mode, fi);

		if (fs->debug && !err)
			fprintf(stderr, "   create[%llu] flags: 0x%x %s\n",
				(unsigned long long) fi->fh, fi->flags, path);

		return err;
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_lock(struct fuse_fs *fs, const char *path,
		 struct fuse_file_info *fi, int cmd, struct flock *lock)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.lock) {
		if (fs->debug)
			fprintf(stderr, "lock[%llu] %s %s start: %llu len: %llu pid: %llu\n",
				(unsigned long long) fi->fh,
				(cmd == F_GETLK ? "F_GETLK" :
				 (cmd == F_SETLK ? "F_SETLK" :
				  (cmd == F_SETLKW ? "F_SETLKW" : "???"))),
				(lock->l_type == F_RDLCK ? "F_RDLCK" :
				 (lock->l_type == F_WRLCK ? "F_WRLCK" :
				  (lock->l_type == F_UNLCK ? "F_UNLCK" :
				   "???"))),
				(unsigned long long) lock->l_start,
				(unsigned long long) lock->l_len,
				(unsigned long long) lock->l_pid);

		return fs->op.lock(path, fi, cmd, lock);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_flock(struct fuse_fs *fs, const char *path,
		  struct fuse_file_info *fi, int op)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.flock) {
		if (fs->debug) {
			int xop = op & ~LOCK_NB;

			fprintf(stderr, "lock[%llu] %s%s\n",
				(unsigned long long) fi->fh,
				xop == LOCK_SH ? "LOCK_SH" :
				(xop == LOCK_EX ? "LOCK_EX" :
				 (xop == LOCK_UN ? "LOCK_UN" : "???")),
				(op & LOCK_NB) ? "|LOCK_NB" : "");
		}
		return fs->op.flock(path, fi, op);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_chown(struct fuse_fs *fs, const char *path, uid_t uid, gid_t gid)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.chown) {
		if (fs->debug)
			fprintf(stderr, "chown %s %lu %lu\n", path,
				(unsigned long) uid, (unsigned long) gid);

		return fs->op.chown(path, uid, gid);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_truncate(struct fuse_fs *fs, const char *path, off64_t size)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.truncate) {
		if (fs->debug)
			fprintf(stderr, "truncate %s %llu\n", path,
				(unsigned long long) size);

		return fs->op.truncate(path, size);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_ftruncate(struct fuse_fs *fs, const char *path, off64_t size,
		      struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.ftruncate) {
		if (fs->debug)
			fprintf(stderr, "ftruncate[%llu] %llu\n",
				(unsigned long long) fi->fh,
				(unsigned long long) size);

		return fs->op.ftruncate(path, size, fi);
	} else if (path && fs->op.truncate) {
		if (fs->debug)
			fprintf(stderr, "truncate %s %llu\n", path,
				(unsigned long long) size);

		return fs->op.truncate(path, size);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_utimens(struct fuse_fs *fs, const char *path,
		    const struct timespec tv[2])
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.utimens) {
		if (fs->debug)
			fprintf(stderr, "utimens %s %li.%09lu %li.%09lu\n",
				path, tv[0].tv_sec, tv[0].tv_nsec,
				tv[1].tv_sec, tv[1].tv_nsec);

		return fs->op.utimens(path, tv);
	} else if(fs->op.utime) {
		struct utimbuf buf;

		if (fs->debug)
			fprintf(stderr, "utime %s %li %li\n", path,
				tv[0].tv_sec, tv[1].tv_sec);

		buf.actime = tv[0].tv_sec;
		buf.modtime = tv[1].tv_sec;
		return fs->op.utime(path, &buf);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_access(struct fuse_fs *fs, const char *path, int mask)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.access) {
		if (fs->debug)
			fprintf(stderr, "access %s 0%o\n", path, mask);

		return fs->op.access(path, mask);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_readlink(struct fuse_fs *fs, const char *path, char *buf,
		     size_t len)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.readlink) {
		if (fs->debug)
			fprintf(stderr, "readlink %s %lu\n", path,
				(unsigned long) len);

		return fs->op.readlink(path, buf, len);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_mknod(struct fuse_fs *fs, const char *path, mode_t mode,
		  dev_t rdev)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.mknod) {
		if (fs->debug)
			fprintf(stderr, "mknod %s 0%o 0x%llx umask=0%03o\n",
				path, mode, (unsigned long long) rdev,
				fuse_get_context()->umask);

		return fs->op.mknod(path, mode, rdev);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_mkdir(struct fuse_fs *fs, const char *path, mode_t mode)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.mkdir) {
		if (fs->debug)
			fprintf(stderr, "mkdir %s 0%o umask=0%03o\n",
				path, mode, fuse_get_context()->umask);

		return fs->op.mkdir(path, mode);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_setxattr(struct fuse_fs *fs, const char *path, const char *name,
		     const char *value, size_t size, int flags)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.setxattr) {
		if (fs->debug)
			fprintf(stderr, "setxattr %s %s %lu 0x%x\n",
				path, name, (unsigned long) size, flags);

		return fs->op.setxattr(path, name, value, size, flags);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_getxattr(struct fuse_fs *fs, const char *path, const char *name,
		     char *value, size_t size)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.getxattr) {
		if (fs->debug)
			fprintf(stderr, "getxattr %s %s %lu\n",
				path, name, (unsigned long) size);

		return fs->op.getxattr(path, name, value, size);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_listxattr(struct fuse_fs *fs, const char *path, char *list,
		      size_t size)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.listxattr) {
		if (fs->debug)
			fprintf(stderr, "listxattr %s %lu\n",
				path, (unsigned long) size);

		return fs->op.listxattr(path, list, size);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_bmap(struct fuse_fs *fs, const char *path, size_t blocksize,
		 uint64_t *idx)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.bmap) {
		if (fs->debug)
			fprintf(stderr, "bmap %s blocksize: %lu index: %llu\n",
				path, (unsigned long) blocksize,
				(unsigned long long) *idx);

		return fs->op.bmap(path, blocksize, idx);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_removexattr(struct fuse_fs *fs, const char *path, const char *name)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.removexattr) {
		if (fs->debug)
			fprintf(stderr, "removexattr %s %s\n", path, name);

		return fs->op.removexattr(path, name);
	} else {
		return -ENOSYS;
	}
}

int fuse_fs_ioctl(struct fuse_fs *fs, const char *path, int cmd, void *arg,
		  struct fuse_file_info *fi, unsigned int flags, void *data)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.ioctl) {
		if (fs->debug)
			fprintf(stderr, "ioctl[%llu] 0x%x flags: 0x%x\n",
				(unsigned long long) fi->fh, cmd, flags);

		return fs->op.ioctl(path, cmd, arg, fi, flags, data);
	} else
		return -ENOSYS;
}

int fuse_fs_poll(struct fuse_fs *fs, const char *path,
		 struct fuse_file_info *fi, struct fuse_pollhandle *ph,
		 unsigned *reventsp)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.poll) {
		int res;

		if (fs->debug)
			fprintf(stderr, "poll[%llu] ph: %p\n",
				(unsigned long long) fi->fh, ph);

		res = fs->op.poll(path, fi, ph, reventsp);

		if (fs->debug && !res)
			fprintf(stderr, "   poll[%llu] revents: 0x%x\n",
				(unsigned long long) fi->fh, *reventsp);

		return res;
	} else
		return -ENOSYS;
}

int fuse_fs_fallocate(struct fuse_fs *fs, const char *path, int mode,
		off64_t offset, off64_t length, struct fuse_file_info *fi)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.fallocate) {
		if (fs->debug)
			fprintf(stderr, "fallocate %s mode %x, offset: %llu, length: %llu\n",
				path,
				mode,
				(unsigned long long) offset,
				(unsigned long long) length);

		return fs->op.fallocate(path, mode, offset, length, fi);
	} else
		return -ENOSYS;
}

static int is_open(struct fuse *f, fuse_ino_t dir, const char *name)
{
	struct node *node;
	int isopen = 0;
	pthread_mutex_lock(&f->lock);
	node = lookup_node(f, dir, name);
	if (node && node->open_count > 0)
		isopen = 1;
	pthread_mutex_unlock(&f->lock);
	return isopen;
}

static char *hidden_name(struct fuse *f, fuse_ino_t dir, const char *oldname,
			 char *newname, size_t bufsize)
{
	struct stat buf;
	struct node *node;
	struct node *newnode;
	char *newpath;
	int res;
	int failctr = 10;

	do {
		pthread_mutex_lock(&f->lock);
		node = lookup_node(f, dir, oldname);
		if (node == NULL) {
			pthread_mutex_unlock(&f->lock);
			return NULL;
		}
		do {
			f->hidectr ++;
			snprintf(newname, bufsize, ".fuse_hidden%08x%08x",
				 (unsigned int) node->nodeid, f->hidectr);
			newnode = lookup_node(f, dir, newname);
		} while(newnode);

		res = try_get_path(f, dir, newname, &newpath, NULL, false);
		pthread_mutex_unlock(&f->lock);
		if (res)
			break;

		res = fuse_fs_getattr(f->fs, newpath, &buf);
		if (res == -ENOENT)
			break;
		free(newpath);
		newpath = NULL;
	} while(res == 0 && --failctr);

	return newpath;
}

static int hide_node(struct fuse *f, const char *oldpath,
		     fuse_ino_t dir, const char *oldname)
{
	char newname[64];
	char *newpath;
	int err = -EBUSY;

	newpath = hidden_name(f, dir, oldname, newname, sizeof(newname));
	if (newpath) {
		err = fuse_fs_rename(f->fs, oldpath, newpath);
		if (!err)
			err = rename_node(f, dir, oldname, dir, newname, 1);
		free(newpath);
	}
	return err;
}

static int mtime_eq(const struct stat *stbuf, const struct timespec *ts)
{
	return stbuf->st_mtime == ts->tv_sec &&
		ST_MTIM_NSEC(stbuf) == ts->tv_nsec;
}

#ifndef CLOCK_MONOTONIC
#define CLOCK_MONOTONIC CLOCK_REALTIME
#endif

static void curr_time(struct timespec *now)
{
	static clockid_t clockid = CLOCK_MONOTONIC;
	int res = clock_gettime(clockid, now);
	if (res == -1 && errno == EINVAL) {
		clockid = CLOCK_REALTIME;
		res = clock_gettime(clockid, now);
	}
	if (res == -1) {
		perror("fuse: clock_gettime");
		abort();
	}
}

static void update_stat(struct node *node, const struct stat *stbuf)
{
	if (node->cache_valid && (!mtime_eq(stbuf, &node->mtime) ||
				  stbuf->st_size != node->size))
		node->cache_valid = 0;
	node->mtime.tv_sec = stbuf->st_mtime;
	node->mtime.tv_nsec = ST_MTIM_NSEC(stbuf);
	node->size = stbuf->st_size;
	curr_time(&node->stat_updated);
}

static int lookup_path(struct fuse *f, fuse_ino_t nodeid,
		       const char *name, const char *path,
		       struct fuse_entry_param *e, struct fuse_file_info *fi)
{
	int res;

	memset(e, 0, sizeof(struct fuse_entry_param));
	if (fi)
		res = fuse_fs_fgetattr(f->fs, path, &e->attr, fi);
	else
		res = fuse_fs_getattr(f->fs, path, &e->attr);
	if (res == 0) {
		struct node *node;

		node = find_node(f, nodeid, name);
		if (node == NULL)
			res = -ENOMEM;
		else {
			e->ino = node->nodeid;
			e->generation = node->generation;
			e->entry_timeout = f->conf.entry_timeout;
			e->attr_timeout = f->conf.attr_timeout;
			if (f->conf.auto_cache) {
				pthread_mutex_lock(&f->lock);
				update_stat(node, &e->attr);
				pthread_mutex_unlock(&f->lock);
			}
			set_stat(f, e->ino, &e->attr);
			if (f->conf.debug)
				fprintf(stderr, "   NODEID: %lu\n",
					(unsigned long) e->ino);
		}
	}
	return res;
}

static struct fuse_context_i *fuse_get_context_internal(void)
{
	struct fuse_context_i *c;

	c = (struct fuse_context_i *) pthread_getspecific(fuse_context_key);
	if (c == NULL) {
		c = (struct fuse_context_i *)
			calloc(1, sizeof(struct fuse_context_i));
		if (c == NULL) {
			/* This is hard to deal with properly, so just
			   abort.  If memory is so low that the
			   context cannot be allocated, there's not
			   much hope for the filesystem anyway */
			fprintf(stderr, "fuse: failed to allocate thread specific data\n");
			abort();
		}
		pthread_setspecific(fuse_context_key, c);
	}
	return c;
}

static void fuse_freecontext(void *data)
{
	free(data);
}

static int fuse_create_context_key(void)
{
	int err = 0;
	pthread_mutex_lock(&fuse_context_lock);
	if (!fuse_context_ref) {
		err = pthread_key_create(&fuse_context_key, fuse_freecontext);
		if (err) {
			fprintf(stderr, "fuse: failed to create thread specific key: %s\n",
				strerror(err));
			pthread_mutex_unlock(&fuse_context_lock);
			return -1;
		}
	}
	fuse_context_ref++;
	pthread_mutex_unlock(&fuse_context_lock);
	return 0;
}

static void fuse_delete_context_key(void)
{
	pthread_mutex_lock(&fuse_context_lock);
	fuse_context_ref--;
	if (!fuse_context_ref) {
		free(pthread_getspecific(fuse_context_key));
		pthread_key_delete(fuse_context_key);
	}
	pthread_mutex_unlock(&fuse_context_lock);
}

static struct fuse *req_fuse_prepare(fuse_req_t req)
{
	struct fuse_context_i *c = fuse_get_context_internal();
	const struct fuse_ctx *ctx = fuse_req_ctx(req);
	c->req = req;
	c->ctx.fuse = req_fuse(req);
	c->ctx.uid = ctx->uid;
	c->ctx.gid = ctx->gid;
	c->ctx.pid = ctx->pid;
	c->ctx.umask = ctx->umask;
	return c->ctx.fuse;
}

static inline void reply_err(fuse_req_t req, int err)
{
	/* fuse_reply_err() uses non-negated errno values */
	fuse_reply_err(req, -err);
}

static void reply_entry(fuse_req_t req, const struct fuse_entry_param *e,
			int err)
{
	if (!err) {
		struct fuse *f = req_fuse(req);
		if (fuse_reply_entry(req, e) == -ENOENT) {
			/* Skip forget for negative result */
			if  (e->ino != 0)
				forget_node(f, e->ino, 1);
		}
	} else
		reply_err(req, err);
}

void fuse_fs_init(struct fuse_fs *fs, struct fuse_conn_info *conn)
{
	fuse_get_context()->private_data = fs->user_data;
	if (!fs->op.write_buf)
		conn->want &= ~FUSE_CAP_SPLICE_READ;
	if (!fs->op.lock)
		conn->want &= ~FUSE_CAP_POSIX_LOCKS;
	if (!fs->op.flock)
		conn->want &= ~FUSE_CAP_FLOCK_LOCKS;
	if (fs->op.init)
		fs->user_data = fs->op.init(conn);
}

static void fuse_lib_init(void *data, struct fuse_conn_info *conn)
{
	struct fuse *f = (struct fuse *) data;
	struct fuse_context_i *c = fuse_get_context_internal();

	memset(c, 0, sizeof(*c));
	c->ctx.fuse = f;
	conn->want |= FUSE_CAP_EXPORT_SUPPORT;
	fuse_fs_init(f->fs, conn);
}

void fuse_fs_destroy(struct fuse_fs *fs)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.destroy)
		fs->op.destroy(fs->user_data);
	if (fs->m)
		fuse_put_module(fs->m);
	free(fs);
}

static void fuse_lib_destroy(void *data)
{
	struct fuse *f = (struct fuse *) data;
	struct fuse_context_i *c = fuse_get_context_internal();

	memset(c, 0, sizeof(*c));
	c->ctx.fuse = f;
	fuse_fs_destroy(f->fs);
	f->fs = NULL;
}

static void fuse_lib_lookup(fuse_req_t req, fuse_ino_t parent,
			    const char *name)
{
	struct fuse *f = req_fuse_prepare(req);
	struct fuse_entry_param e;
	char *path;
	int err;
	struct node *dot = NULL;

	if (name[0] == '.') {
		int len = strlen(name);

		if (len == 1 || (name[1] == '.' && len == 2)) {
			pthread_mutex_lock(&f->lock);
			if (len == 1) {
				if (f->conf.debug)
					fprintf(stderr, "LOOKUP-DOT\n");
				dot = get_node_nocheck(f, parent);
				if (dot == NULL) {
					pthread_mutex_unlock(&f->lock);
					reply_entry(req, &e, -ESTALE);
					return;
				}
				dot->refctr++;
			} else {
				if (f->conf.debug)
					fprintf(stderr, "LOOKUP-DOTDOT\n");
				parent = get_node(f, parent)->parent->nodeid;
			}
			pthread_mutex_unlock(&f->lock);
			name = NULL;
		}
	}

	err = get_path_name(f, parent, name, &path);
	if (!err) {
		struct fuse_intr_data d;
		if (f->conf.debug)
			fprintf(stderr, "LOOKUP %s\n", path);
		fuse_prepare_interrupt(f, req, &d);
		err = lookup_path(f, parent, name, path, &e, NULL);
		if (err == -ENOENT && f->conf.negative_timeout != 0.0) {
			e.ino = 0;
			e.entry_timeout = f->conf.negative_timeout;
			err = 0;
		}
		fuse_finish_interrupt(f, req, &d);
		free_path(f, parent, path);
	}
	if (dot) {
		pthread_mutex_lock(&f->lock);
		unref_node(f, dot);
		pthread_mutex_unlock(&f->lock);
	}
	reply_entry(req, &e, err);
}

static void do_forget(struct fuse *f, fuse_ino_t ino, uint64_t nlookup)
{
	if (f->conf.debug)
		fprintf(stderr, "FORGET %llu/%llu\n", (unsigned long long)ino,
			(unsigned long long) nlookup);
	forget_node(f, ino, nlookup);
}

static void fuse_lib_forget(fuse_req_t req, fuse_ino_t ino,
			    unsigned long nlookup)
{
	do_forget(req_fuse(req), ino, nlookup);
	fuse_reply_none(req);
}

static void fuse_lib_forget_multi(fuse_req_t req, size_t count,
				  struct fuse_forget_data *forgets)
{
	struct fuse *f = req_fuse(req);
	size_t i;

	for (i = 0; i < count; i++)
		do_forget(f, forgets[i].ino, forgets[i].nlookup);

	fuse_reply_none(req);
}


static void fuse_lib_getattr(fuse_req_t req, fuse_ino_t ino,
			     struct fuse_file_info *fi)
{
	struct fuse *f = req_fuse_prepare(req);
	struct stat buf;
	char *path;
	int err;

	memset(&buf, 0, sizeof(buf));

	if (fi != NULL && f->fs->op.fgetattr)
		err = get_path_nullok(f, ino, &path);
	else
		err = get_path(f, ino, &path);
	if (!err) {
		struct fuse_intr_data d;
		fuse_prepare_interrupt(f, req, &d);
		if (fi)
			err = fuse_fs_fgetattr(f->fs, path, &buf, fi);
		else
			err = fuse_fs_getattr(f->fs, path, &buf);
		fuse_finish_interrupt(f, req, &d);
		free_path(f, ino, path);
	}
	if (!err) {
		struct node *node;

		pthread_mutex_lock(&f->lock);
		node = get_node(f, ino);
		if (node->is_hidden && buf.st_nlink > 0)
			buf.st_nlink--;
		if (f->conf.auto_cache)
			update_stat(node, &buf);
		pthread_mutex_unlock(&f->lock);
		set_stat(f, ino, &buf);
		fuse_reply_attr(req, &buf, f->conf.attr_timeout);
	} else
		reply_err(req, err);
}

int fuse_fs_chmod(struct fuse_fs *fs, const char *path, mode_t mode)
{
	fuse_get_context()->private_data = fs->user_data;
	if (fs->op.chmod)
		return fs->op.chmod(path, mode);
	else
		return -ENOSYS;
}

static void fuse_lib_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr,
			     int valid, struct fuse_file_info *fi)
{
	struct fuse *f = req_fuse_prepare(req);
	struct stat buf;
	char *path;
	int err;

	if (valid == FUSE_SET_ATTR_SIZE && fi != NULL &&
	    f->fs->op.ftruncate && f->fs->op.fgetattr)
		err = get_path_nullok(f, ino, &path);
	else
		err = get_path(f, ino, &path);
	if (!err) {
		struct fuse_intr_data d;
		fuse_prepare_interrupt(f, req, &d);
		err = 0;
		if (!err && (valid & FUSE_SET_ATTR_MODE))
			err = fuse_fs_chmod(f->fs, path, attr->st_mode);
		if (!err && (valid & (FUSE_SET_ATTR_UID | FUSE_SET_ATTR_GID))) {
			uid_t uid = (valid & FUSE_SET_ATTR_UID) ?
				attr->st_uid : (uid_t) -1;
			gid_t gid = (valid & FUSE_SET_ATTR_GID) ?
				attr->st_gid : (gid_t) -1;
			err = fuse_fs_chown(f->fs, path, uid, gid);
		}
		if (!err && (valid & FUSE_SET_ATTR_SIZE)) {
			if (fi)
				err = fuse_fs_ftruncate(f->fs, path,
							attr->st_size, fi);
			else
				err = fuse_fs_truncate(f->fs, path,
						       attr->st_size);
		}
#ifdef HAVE_UTIMENSAT
		if (!err && f->utime_omit_ok &&
		    (valid & (FUSE_SET_ATTR_ATIME | FUSE_SET_ATTR_MTIME))) {
			struct timespec tv[2];

			tv[0].tv_sec = 0;
			tv[1].tv_sec = 0;
			tv[0].tv_nsec = UTIME_OMIT;
			tv[1].tv_nsec = UTIME_OMIT;

			if (valid & FUSE_SET_ATTR_ATIME_NOW)
				tv[0].tv_nsec = UTIME_NOW;
			else if (valid & FUSE_SET_ATTR_ATIME)
				tv[0] = attr->st_atim;

			if (valid & FUSE_SET_ATTR_MTIME_NOW)
				tv[1].tv_nsec = UTIME_NOW;
			else if (valid & FUSE_SET_ATTR_MTIME)
				tv[1] = attr->st_mtim;

			err = fuse_fs_utimens(f->fs, path, tv);
		} else
#endif
		if (!err &&
		    (valid & (FUSE_SET_ATTR_ATIME | FUSE_SET_ATTR_MTIME)) ==
		    (FUSE_SET_ATTR_ATIME | FUSE_SET_ATTR_MTIME)) {
			struct timespec tv[2];
			tv[0].tv_sec = attr->st_atime;
			tv[0].tv_nsec = ST_ATIM_NSEC(attr);
			tv[1].tv_sec = attr->st_mtime;
			tv[1].tv_nsec = ST_MTIM_NSEC(attr);
			err = fuse_fs_utimens(f->fs, path, tv);
		}
		if (!err) {
			if (fi)
				err = fuse_fs_fgetattr(f->fs, path, &buf, fi);
			else
				err = fuse_fs_getattr(f->fs, path, &buf);
		}
		fuse_finish_interrupt(f, req, &d);
		free_path(f, ino, path);