Commit cc080e9e authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

fuse: introduce per-instance fuse_dev structure



Allow fuse device clones to refer to be distinguished.  This patch just
adds the infrastructure by associating a separate "struct fuse_dev" with
each clone.
Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
Reviewed-by: default avatarAshish Samant <ashish.samant@oracle.com>
parent 00c570f4
......@@ -489,6 +489,7 @@ static void cuse_fc_release(struct fuse_conn *fc)
*/
static int cuse_channel_open(struct inode *inode, struct file *file)
{
struct fuse_dev *fud;
struct cuse_conn *cc;
int rc;
......@@ -499,16 +500,22 @@ static int cuse_channel_open(struct inode *inode, struct file *file)
fuse_conn_init(&cc->fc);
fud = fuse_dev_alloc(&cc->fc);
if (!fud) {
kfree(cc);
return -ENOMEM;
}
INIT_LIST_HEAD(&cc->list);
cc->fc.release = cuse_fc_release;
cc->fc.initialized = 1;
rc = cuse_send_init(cc);
if (rc) {
fuse_conn_put(&cc->fc);
fuse_dev_free(fud);
return rc;
}
file->private_data = &cc->fc; /* channel owns base reference to cc */
file->private_data = fud;
return 0;
}
......@@ -526,7 +533,8 @@ static int cuse_channel_open(struct inode *inode, struct file *file)
*/
static int cuse_channel_release(struct inode *inode, struct file *file)
{
struct cuse_conn *cc = fc_to_cc(file->private_data);
struct fuse_dev *fud = file->private_data;
struct cuse_conn *cc = fc_to_cc(fud->fc);
int rc;
/* remove from the conntbl, no more access from this point on */
......
......@@ -25,13 +25,13 @@ MODULE_ALIAS("devname:fuse");
static struct kmem_cache *fuse_req_cachep;
static struct fuse_conn *fuse_get_conn(struct file *file)
static struct fuse_dev *fuse_get_dev(struct file *file)
{
/*
* Lockless access is OK, because file->private data is set
* once during mount and is valid until the file is released.
*/
return file->private_data;
return ACCESS_ONCE(file->private_data);
}
static void fuse_request_init(struct fuse_req *req, struct page **pages,
......@@ -1348,8 +1348,9 @@ static ssize_t fuse_dev_read(struct kiocb *iocb, struct iov_iter *to)
{
struct fuse_copy_state cs;
struct file *file = iocb->ki_filp;
struct fuse_conn *fc = fuse_get_conn(file);
if (!fc)
struct fuse_dev *fud = fuse_get_dev(file);
if (!fud)
return -EPERM;
if (!iter_is_iovec(to))
......@@ -1357,7 +1358,7 @@ static ssize_t fuse_dev_read(struct kiocb *iocb, struct iov_iter *to)
fuse_copy_init(&cs, 1, to);
return fuse_dev_do_read(fc, file, &cs, iov_iter_count(to));
return fuse_dev_do_read(fud->fc, file, &cs, iov_iter_count(to));
}
static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
......@@ -1369,8 +1370,9 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
int do_wakeup = 0;
struct pipe_buffer *bufs;
struct fuse_copy_state cs;
struct fuse_conn *fc = fuse_get_conn(in);
if (!fc)
struct fuse_dev *fud = fuse_get_dev(in);
if (!fud)
return -EPERM;
bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
......@@ -1380,7 +1382,7 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
fuse_copy_init(&cs, 1, NULL);
cs.pipebufs = bufs;
cs.pipe = pipe;
ret = fuse_dev_do_read(fc, in, &cs, len);
ret = fuse_dev_do_read(fud->fc, in, &cs, len);
if (ret < 0)
goto out;
......@@ -1954,8 +1956,9 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
static ssize_t fuse_dev_write(struct kiocb *iocb, struct iov_iter *from)
{
struct fuse_copy_state cs;
struct fuse_conn *fc = fuse_get_conn(iocb->ki_filp);
if (!fc)
struct fuse_dev *fud = fuse_get_dev(iocb->ki_filp);
if (!fud)
return -EPERM;
if (!iter_is_iovec(from))
......@@ -1963,7 +1966,7 @@ static ssize_t fuse_dev_write(struct kiocb *iocb, struct iov_iter *from)
fuse_copy_init(&cs, 0, from);
return fuse_dev_do_write(fc, &cs, iov_iter_count(from));
return fuse_dev_do_write(fud->fc, &cs, iov_iter_count(from));
}
static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
......@@ -1974,12 +1977,12 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
unsigned idx;
struct pipe_buffer *bufs;
struct fuse_copy_state cs;
struct fuse_conn *fc;
struct fuse_dev *fud;
size_t rem;
ssize_t ret;
fc = fuse_get_conn(out);
if (!fc)
fud = fuse_get_dev(out);
if (!fud)
return -EPERM;
bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
......@@ -2034,7 +2037,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
if (flags & SPLICE_F_MOVE)
cs.move_pages = 1;
ret = fuse_dev_do_write(fc, &cs, len);
ret = fuse_dev_do_write(fud->fc, &cs, len);
for (idx = 0; idx < nbuf; idx++) {
struct pipe_buffer *buf = &bufs[idx];
......@@ -2049,11 +2052,12 @@ static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
{
unsigned mask = POLLOUT | POLLWRNORM;
struct fuse_iqueue *fiq;
struct fuse_conn *fc = fuse_get_conn(file);
if (!fc)
struct fuse_dev *fud = fuse_get_dev(file);
if (!fud)
return POLLERR;
fiq = &fc->iq;
fiq = &fud->fc->iq;
poll_wait(file, &fiq->waitq, wait);
spin_lock(&fiq->waitq.lock);
......@@ -2175,12 +2179,15 @@ EXPORT_SYMBOL_GPL(fuse_abort_conn);
int fuse_dev_release(struct inode *inode, struct file *file)
{
struct fuse_conn *fc = fuse_get_conn(file);
if (fc) {
struct fuse_dev *fud = fuse_get_dev(file);
if (fud) {
struct fuse_conn *fc = fud->fc;
WARN_ON(!list_empty(&fc->pq.io));
WARN_ON(fc->iq.fasync != NULL);
fuse_abort_conn(fc);
fuse_conn_put(fc);
fuse_dev_free(fud);
}
return 0;
......@@ -2189,20 +2196,27 @@ EXPORT_SYMBOL_GPL(fuse_dev_release);
static int fuse_dev_fasync(int fd, struct file *file, int on)
{
struct fuse_conn *fc = fuse_get_conn(file);
if (!fc)
struct fuse_dev *fud = fuse_get_dev(file);
if (!fud)
return -EPERM;
/* No locking - fasync_helper does its own locking */
return fasync_helper(fd, file, on, &fc->iq.fasync);
return fasync_helper(fd, file, on, &fud->fc->iq.fasync);
}
static int fuse_device_clone(struct fuse_conn *fc, struct file *new)
{
struct fuse_dev *fud;
if (new->private_data)
return -EINVAL;
new->private_data = fuse_conn_get(fc);
fud = fuse_dev_alloc(fc);
if (!fud)
return -ENOMEM;
new->private_data = fud;
return 0;
}
......@@ -2221,11 +2235,11 @@ static long fuse_dev_ioctl(struct file *file, unsigned int cmd,
err = -EINVAL;
if (old) {
struct fuse_conn *fc = fuse_get_conn(old);
struct fuse_dev *fud = fuse_get_dev(old);
if (fc) {
if (fud) {
mutex_lock(&fuse_mutex);
err = fuse_device_clone(fc, file);
err = fuse_device_clone(fud->fc, file);
mutex_unlock(&fuse_mutex);
}
fput(old);
......
......@@ -417,6 +417,17 @@ struct fuse_pqueue {
struct list_head io;
};
/**
* Fuse device instance
*/
struct fuse_dev {
/** Fuse connection for this device */
struct fuse_conn *fc;
/** list entry on fc->devices */
struct list_head entry;
};
/**
* A Fuse connection.
*
......@@ -629,6 +640,9 @@ struct fuse_conn {
/** Read/write semaphore to hold when accessing sb. */
struct rw_semaphore killsb;
/** List of device instances belonging to this connection */
struct list_head devices;
};
static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
......@@ -841,6 +855,9 @@ void fuse_conn_init(struct fuse_conn *fc);
*/
void fuse_conn_put(struct fuse_conn *fc);
struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc);
void fuse_dev_free(struct fuse_dev *fud);
/**
* Add connection to control filesystem
*/
......
......@@ -598,6 +598,7 @@ void fuse_conn_init(struct fuse_conn *fc)
fuse_pqueue_init(&fc->pq);
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;
......@@ -945,6 +946,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
static void fuse_free_conn(struct fuse_conn *fc)
{
WARN_ON(!list_empty(&fc->devices));
kfree_rcu(fc, rcu);
}
......@@ -990,8 +992,41 @@ static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
return 0;
}
struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc)
{
struct fuse_dev *fud;
fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL);
if (fud) {
fud->fc = fuse_conn_get(fc);
spin_lock(&fc->lock);
list_add_tail(&fud->entry, &fc->devices);
spin_unlock(&fc->lock);
}
return fud;
}
EXPORT_SYMBOL_GPL(fuse_dev_alloc);
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);
}
EXPORT_SYMBOL_GPL(fuse_dev_free);
static int fuse_fill_super(struct super_block *sb, void *data, int silent)
{
struct fuse_dev *fud;
struct fuse_conn *fc;
struct inode *root;
struct fuse_mount_data d;
......@@ -1043,11 +1078,15 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
fuse_conn_init(fc);
fc->release = fuse_free_conn;
fud = fuse_dev_alloc(fc);
if (!fud)
goto err_put_conn;
fc->dev = sb->s_dev;
fc->sb = sb;
err = fuse_bdi_init(fc, sb);
if (err)
goto err_put_conn;
goto err_dev_free;
sb->s_bdi = &fc->bdi;
......@@ -1068,7 +1107,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
root = fuse_get_root_inode(sb, d.rootmode);
root_dentry = d_make_root(root);
if (!root_dentry)
goto err_put_conn;
goto err_dev_free;
/* only now - we want root dentry with NULL ->d_op */
sb->s_d_op = &fuse_dentry_operations;
......@@ -1094,7 +1133,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
list_add_tail(&fc->entry, &fuse_conn_list);
sb->s_root = root_dentry;
file->private_data = fuse_conn_get(fc);
file->private_data = fud;
mutex_unlock(&fuse_mutex);
/*
* atomic_dec_and_test() in fput() provides the necessary
......@@ -1113,6 +1152,8 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
fuse_request_free(init_req);
err_put_root:
dput(root_dentry);
err_dev_free:
fuse_dev_free(fud);
err_put_conn:
fuse_bdi_destroy(fc);
fuse_conn_put(fc);
......
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