/*
FUSE: Filesystem in Userspace
- Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu>
+ Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu>
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
MODULE_DESCRIPTION("Filesystem in Userspace");
MODULE_LICENSE("GPL");
-spinlock_t fuse_lock;
static kmem_cache_t *fuse_inode_cachep;
+static struct subsystem connections_subsys;
+
+struct fuse_conn_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct fuse_conn *, char *);
+ ssize_t (*store)(struct fuse_conn *, const char *, size_t);
+};
#define FUSE_SUPER_MAGIC 0x65735546
return inode;
}
+static void fuse_umount_begin(struct super_block *sb)
+{
+ fuse_abort_conn(get_fuse_conn_super(sb));
+}
+
static void fuse_put_super(struct super_block *sb)
{
struct fuse_conn *fc = get_fuse_conn_super(sb);
down_write(&fc->sbput_sem);
while (!list_empty(&fc->background))
- fuse_release_background(list_entry(fc->background.next,
+ fuse_release_background(fc,
+ list_entry(fc->background.next,
struct fuse_req, bg_entry));
- spin_lock(&fuse_lock);
+ spin_lock(&fc->lock);
fc->mounted = 0;
+ fc->connected = 0;
+ spin_unlock(&fc->lock);
+ up_write(&fc->sbput_sem);
/* Flush all readers on this fs */
+ kill_fasync(&fc->fasync, SIGIO, POLL_IN);
wake_up_all(&fc->waitq);
- up_write(&fc->sbput_sem);
- fuse_release_conn(fc);
- spin_unlock(&fuse_lock);
+ kobject_del(&fc->kobj);
+ kobject_put(&fc->kobj);
}
static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
struct fuse_statfs_out outarg;
int err;
- req = fuse_get_request(fc);
- if (!req)
- return -EINTR;
+ req = fuse_get_req(fc);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
memset(&outarg, 0, sizeof(outarg));
req->in.numargs = 0;
return 0;
}
-static void free_conn(struct fuse_conn *fc)
-{
- while (!list_empty(&fc->unused_list)) {
- struct fuse_req *req;
- req = list_entry(fc->unused_list.next, struct fuse_req, list);
- list_del(&req->list);
- fuse_request_free(req);
- }
- kfree(fc);
-}
-
-/* Must be called with the fuse lock held */
-void fuse_release_conn(struct fuse_conn *fc)
+static void fuse_conn_release(struct kobject *kobj)
{
- fc->count--;
- if (!fc->count)
- free_conn(fc);
+ kfree(get_fuse_conn_kobj(kobj));
}
static struct fuse_conn *new_conn(void)
struct fuse_conn *fc;
fc = kzalloc(sizeof(*fc), GFP_KERNEL);
- if (fc != NULL) {
- int i;
+ if (fc) {
+ spin_lock_init(&fc->lock);
init_waitqueue_head(&fc->waitq);
+ init_waitqueue_head(&fc->blocked_waitq);
INIT_LIST_HEAD(&fc->pending);
INIT_LIST_HEAD(&fc->processing);
- INIT_LIST_HEAD(&fc->unused_list);
+ INIT_LIST_HEAD(&fc->io);
INIT_LIST_HEAD(&fc->background);
- sema_init(&fc->outstanding_sem, 1); /* One for INIT */
init_rwsem(&fc->sbput_sem);
- for (i = 0; i < FUSE_MAX_OUTSTANDING; i++) {
- struct fuse_req *req = fuse_request_alloc();
- if (!req) {
- free_conn(fc);
- return NULL;
- }
- list_add(&req->list, &fc->unused_list);
- }
+ kobj_set_kset_s(fc, connections_subsys);
+ kobject_init(&fc->kobj);
+ atomic_set(&fc->num_waiting, 0);
fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
fc->bdi.unplug_io_fn = default_unplug_io_fn;
fc->reqctr = 0;
+ fc->blocked = 1;
}
return fc;
}
-static struct fuse_conn *get_conn(struct file *file, struct super_block *sb)
-{
- struct fuse_conn *fc;
-
- if (file->f_op != &fuse_dev_operations)
- return ERR_PTR(-EINVAL);
- fc = new_conn();
- if (fc == NULL)
- return ERR_PTR(-ENOMEM);
- spin_lock(&fuse_lock);
- if (file->private_data) {
- free_conn(fc);
- fc = ERR_PTR(-EINVAL);
- } else {
- file->private_data = fc;
- sb->s_fs_info = fc;
- fc->mounted = 1;
- fc->connected = 1;
- fc->count = 2;
- }
- spin_unlock(&fuse_lock);
- return fc;
-}
-
static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
{
struct fuse_attr attr;
.read_inode = fuse_read_inode,
.clear_inode = fuse_clear_inode,
.put_super = fuse_put_super,
+ .umount_begin = fuse_umount_begin,
.statfs = fuse_statfs,
.show_options = fuse_show_options,
};
+static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
+{
+ struct fuse_init_out *arg = &req->misc.init_out;
+
+ if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
+ fc->conn_error = 1;
+ else {
+ unsigned long ra_pages;
+
+ if (arg->minor >= 6) {
+ ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
+ if (arg->flags & FUSE_ASYNC_READ)
+ fc->async_read = 1;
+ } else
+ ra_pages = fc->max_read / PAGE_CACHE_SIZE;
+
+ fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
+ fc->minor = arg->minor;
+ fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
+ }
+ fuse_put_request(fc, req);
+ fc->blocked = 0;
+ wake_up_all(&fc->blocked_waitq);
+}
+
+static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
+{
+ struct fuse_init_in *arg = &req->misc.init_in;
+
+ arg->major = FUSE_KERNEL_VERSION;
+ arg->minor = FUSE_KERNEL_MINOR_VERSION;
+ arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
+ arg->flags |= FUSE_ASYNC_READ;
+ req->in.h.opcode = FUSE_INIT;
+ req->in.numargs = 1;
+ req->in.args[0].size = sizeof(*arg);
+ req->in.args[0].value = arg;
+ req->out.numargs = 1;
+ /* Variable length arguement 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 */
+ req->out.argvar = 1;
+ req->out.args[0].size = sizeof(struct fuse_init_out);
+ req->out.args[0].value = &req->misc.init_out;
+ req->end = process_init_reply;
+ request_send_background(fc, req);
+}
+
+static unsigned long long conn_id(void)
+{
+ /* BKL is held for ->get_sb() */
+ static unsigned long long ctr = 1;
+ return ctr++;
+}
+
static int fuse_fill_super(struct super_block *sb, void *data, int silent)
{
struct fuse_conn *fc;
struct inode *root;
struct fuse_mount_data d;
struct file *file;
+ struct dentry *root_dentry;
+ struct fuse_req *init_req;
int err;
if (!parse_fuse_opt((char *) data, &d))
if (!file)
return -EINVAL;
- fc = get_conn(file, sb);
- fput(file);
- if (IS_ERR(fc))
- return PTR_ERR(fc);
+ if (file->f_op != &fuse_dev_operations)
+ return -EINVAL;
+
+ fc = new_conn();
+ if (!fc)
+ return -ENOMEM;
fc->flags = d.flags;
fc->user_id = d.user_id;
fc->group_id = d.group_id;
fc->max_read = d.max_read;
- if (fc->max_read / PAGE_CACHE_SIZE < fc->bdi.ra_pages)
- fc->bdi.ra_pages = fc->max_read / PAGE_CACHE_SIZE;
+
+ /* Used by get_root_inode() */
+ sb->s_fs_info = fc;
err = -ENOMEM;
root = get_root_inode(sb, d.rootmode);
- if (root == NULL)
+ if (!root)
goto err;
- sb->s_root = d_alloc_root(root);
- if (!sb->s_root) {
+ root_dentry = d_alloc_root(root);
+ if (!root_dentry) {
iput(root);
goto err;
}
- fuse_send_init(fc);
+
+ init_req = fuse_request_alloc();
+ if (!init_req)
+ goto err_put_root;
+
+ err = kobject_set_name(&fc->kobj, "%llu", conn_id());
+ if (err)
+ goto err_free_req;
+
+ err = kobject_add(&fc->kobj);
+ if (err)
+ goto err_free_req;
+
+ /* Setting file->private_data can't race with other mount()
+ instances, since BKL is held for ->get_sb() */
+ err = -EINVAL;
+ if (file->private_data)
+ goto err_kobject_del;
+
+ sb->s_root = root_dentry;
+ fc->mounted = 1;
+ fc->connected = 1;
+ kobject_get(&fc->kobj);
+ file->private_data = fc;
+ /*
+ * atomic_dec_and_test() in fput() provides the necessary
+ * memory barrier for file->private_data to be visible on all
+ * CPUs after this
+ */
+ fput(file);
+
+ fuse_send_init(fc, init_req);
+
return 0;
+ err_kobject_del:
+ kobject_del(&fc->kobj);
+ err_free_req:
+ fuse_request_free(init_req);
+ err_put_root:
+ dput(root_dentry);
err:
- spin_lock(&fuse_lock);
- fuse_release_conn(fc);
- spin_unlock(&fuse_lock);
+ fput(file);
+ kobject_put(&fc->kobj);
return err;
}
.kill_sb = kill_anon_super,
};
+static ssize_t fuse_conn_waiting_show(struct fuse_conn *fc, char *page)
+{
+ return sprintf(page, "%i\n", atomic_read(&fc->num_waiting));
+}
+
+static ssize_t fuse_conn_abort_store(struct fuse_conn *fc, const char *page,
+ size_t count)
+{
+ fuse_abort_conn(fc);
+ return count;
+}
+
+static struct fuse_conn_attr fuse_conn_waiting =
+ __ATTR(waiting, 0400, fuse_conn_waiting_show, NULL);
+static struct fuse_conn_attr fuse_conn_abort =
+ __ATTR(abort, 0600, NULL, fuse_conn_abort_store);
+
+static struct attribute *fuse_conn_attrs[] = {
+ &fuse_conn_waiting.attr,
+ &fuse_conn_abort.attr,
+ NULL,
+};
+
+static ssize_t fuse_conn_attr_show(struct kobject *kobj,
+ struct attribute *attr,
+ char *page)
+{
+ struct fuse_conn_attr *fca =
+ container_of(attr, struct fuse_conn_attr, attr);
+
+ if (fca->show)
+ return fca->show(get_fuse_conn_kobj(kobj), page);
+ else
+ return -EACCES;
+}
+
+static ssize_t fuse_conn_attr_store(struct kobject *kobj,
+ struct attribute *attr,
+ const char *page, size_t count)
+{
+ struct fuse_conn_attr *fca =
+ container_of(attr, struct fuse_conn_attr, attr);
+
+ if (fca->store)
+ return fca->store(get_fuse_conn_kobj(kobj), page, count);
+ else
+ return -EACCES;
+}
+
+static struct sysfs_ops fuse_conn_sysfs_ops = {
+ .show = &fuse_conn_attr_show,
+ .store = &fuse_conn_attr_store,
+};
+
+static struct kobj_type ktype_fuse_conn = {
+ .release = fuse_conn_release,
+ .sysfs_ops = &fuse_conn_sysfs_ops,
+ .default_attrs = fuse_conn_attrs,
+};
+
+static decl_subsys(fuse, NULL, NULL);
+static decl_subsys(connections, &ktype_fuse_conn, NULL);
+
static void fuse_inode_init_once(void *foo, kmem_cache_t *cachep,
unsigned long flags)
{
kmem_cache_destroy(fuse_inode_cachep);
}
+static int fuse_sysfs_init(void)
+{
+ int err;
+
+ kset_set_kset_s(&fuse_subsys, fs_subsys);
+ err = subsystem_register(&fuse_subsys);
+ if (err)
+ goto out_err;
+
+ kset_set_kset_s(&connections_subsys, fuse_subsys);
+ err = subsystem_register(&connections_subsys);
+ if (err)
+ goto out_fuse_unregister;
+
+ return 0;
+
+ out_fuse_unregister:
+ subsystem_unregister(&fuse_subsys);
+ out_err:
+ return err;
+}
+
+static void fuse_sysfs_cleanup(void)
+{
+ subsystem_unregister(&connections_subsys);
+ subsystem_unregister(&fuse_subsys);
+}
+
static int __init fuse_init(void)
{
int res;
printk("fuse init (API version %i.%i)\n",
FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
- spin_lock_init(&fuse_lock);
res = fuse_fs_init();
if (res)
goto err;
if (res)
goto err_fs_cleanup;
+ res = fuse_sysfs_init();
+ if (res)
+ goto err_dev_cleanup;
+
return 0;
+ err_dev_cleanup:
+ fuse_dev_cleanup();
err_fs_cleanup:
fuse_fs_cleanup();
err:
{
printk(KERN_DEBUG "fuse exit\n");
+ fuse_sysfs_cleanup();
fuse_fs_cleanup();
fuse_dev_cleanup();
}