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Diffstat (limited to 'kernel/fs/fuse/dev.c')
-rw-r--r--kernel/fs/fuse/dev.c833
1 files changed, 439 insertions, 394 deletions
diff --git a/kernel/fs/fuse/dev.c b/kernel/fs/fuse/dev.c
index c8b68ab2e..ebb5e3745 100644
--- a/kernel/fs/fuse/dev.c
+++ b/kernel/fs/fuse/dev.c
@@ -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,
@@ -48,6 +48,7 @@ static void fuse_request_init(struct fuse_req *req, struct page **pages,
req->pages = pages;
req->page_descs = page_descs;
req->max_pages = npages;
+ __set_bit(FR_PENDING, &req->flags);
}
static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags)
@@ -168,6 +169,10 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
if (!fc->connected)
goto out;
+ err = -ECONNREFUSED;
+ if (fc->conn_error)
+ goto out;
+
req = fuse_request_alloc(npages);
err = -ENOMEM;
if (!req) {
@@ -177,8 +182,10 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
}
fuse_req_init_context(req);
- req->waiting = 1;
- req->background = for_background;
+ __set_bit(FR_WAITING, &req->flags);
+ if (for_background)
+ __set_bit(FR_BACKGROUND, &req->flags);
+
return req;
out:
@@ -268,15 +275,15 @@ struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
req = get_reserved_req(fc, file);
fuse_req_init_context(req);
- req->waiting = 1;
- req->background = 0;
+ __set_bit(FR_WAITING, &req->flags);
+ __clear_bit(FR_BACKGROUND, &req->flags);
return req;
}
void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
{
if (atomic_dec_and_test(&req->count)) {
- if (unlikely(req->background)) {
+ if (test_bit(FR_BACKGROUND, &req->flags)) {
/*
* We get here in the unlikely case that a background
* request was allocated but not sent
@@ -287,8 +294,10 @@ void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
spin_unlock(&fc->lock);
}
- if (req->waiting)
+ if (test_bit(FR_WAITING, &req->flags)) {
+ __clear_bit(FR_WAITING, &req->flags);
atomic_dec(&fc->num_waiting);
+ }
if (req->stolen_file)
put_reserved_req(fc, req);
@@ -309,46 +318,38 @@ static unsigned len_args(unsigned numargs, struct fuse_arg *args)
return nbytes;
}
-static u64 fuse_get_unique(struct fuse_conn *fc)
+static u64 fuse_get_unique(struct fuse_iqueue *fiq)
{
- fc->reqctr++;
- /* zero is special */
- if (fc->reqctr == 0)
- fc->reqctr = 1;
-
- return fc->reqctr;
+ return ++fiq->reqctr;
}
-static void queue_request(struct fuse_conn *fc, struct fuse_req *req)
+static void queue_request(struct fuse_iqueue *fiq, struct fuse_req *req)
{
req->in.h.len = sizeof(struct fuse_in_header) +
len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
- list_add_tail(&req->list, &fc->pending);
- req->state = FUSE_REQ_PENDING;
- if (!req->waiting) {
- req->waiting = 1;
- atomic_inc(&fc->num_waiting);
- }
- wake_up(&fc->waitq);
- kill_fasync(&fc->fasync, SIGIO, POLL_IN);
+ list_add_tail(&req->list, &fiq->pending);
+ wake_up_locked(&fiq->waitq);
+ kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
}
void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
u64 nodeid, u64 nlookup)
{
+ struct fuse_iqueue *fiq = &fc->iq;
+
forget->forget_one.nodeid = nodeid;
forget->forget_one.nlookup = nlookup;
- spin_lock(&fc->lock);
- if (fc->connected) {
- fc->forget_list_tail->next = forget;
- fc->forget_list_tail = forget;
- wake_up(&fc->waitq);
- kill_fasync(&fc->fasync, SIGIO, POLL_IN);
+ spin_lock(&fiq->waitq.lock);
+ if (fiq->connected) {
+ fiq->forget_list_tail->next = forget;
+ fiq->forget_list_tail = forget;
+ wake_up_locked(&fiq->waitq);
+ kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
} else {
kfree(forget);
}
- spin_unlock(&fc->lock);
+ spin_unlock(&fiq->waitq.lock);
}
static void flush_bg_queue(struct fuse_conn *fc)
@@ -356,12 +357,15 @@ static void flush_bg_queue(struct fuse_conn *fc)
while (fc->active_background < fc->max_background &&
!list_empty(&fc->bg_queue)) {
struct fuse_req *req;
+ struct fuse_iqueue *fiq = &fc->iq;
req = list_entry(fc->bg_queue.next, struct fuse_req, list);
list_del(&req->list);
fc->active_background++;
- req->in.h.unique = fuse_get_unique(fc);
- queue_request(fc, req);
+ spin_lock(&fiq->waitq.lock);
+ req->in.h.unique = fuse_get_unique(fiq);
+ queue_request(fiq, req);
+ spin_unlock(&fiq->waitq.lock);
}
}
@@ -372,20 +376,22 @@ static void flush_bg_queue(struct fuse_conn *fc)
* was closed. The requester thread is woken up (if still waiting),
* the 'end' callback is called if given, else the reference to the
* request is released
- *
- * Called with fc->lock, unlocks it
*/
static void request_end(struct fuse_conn *fc, struct fuse_req *req)
-__releases(fc->lock)
{
- void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
- req->end = NULL;
- list_del(&req->list);
- list_del(&req->intr_entry);
- req->state = FUSE_REQ_FINISHED;
- if (req->background) {
- req->background = 0;
+ struct fuse_iqueue *fiq = &fc->iq;
+
+ if (test_and_set_bit(FR_FINISHED, &req->flags))
+ return;
+ spin_lock(&fiq->waitq.lock);
+ list_del_init(&req->intr_entry);
+ spin_unlock(&fiq->waitq.lock);
+ WARN_ON(test_bit(FR_PENDING, &req->flags));
+ WARN_ON(test_bit(FR_SENT, &req->flags));
+ if (test_bit(FR_BACKGROUND, &req->flags)) {
+ spin_lock(&fc->lock);
+ clear_bit(FR_BACKGROUND, &req->flags);
if (fc->num_background == fc->max_background)
fc->blocked = 0;
@@ -401,122 +407,105 @@ __releases(fc->lock)
fc->num_background--;
fc->active_background--;
flush_bg_queue(fc);
+ spin_unlock(&fc->lock);
}
- spin_unlock(&fc->lock);
wake_up(&req->waitq);
- if (end)
- end(fc, req);
+ if (req->end)
+ req->end(fc, req);
fuse_put_request(fc, req);
}
-static void wait_answer_interruptible(struct fuse_conn *fc,
- struct fuse_req *req)
-__releases(fc->lock)
-__acquires(fc->lock)
-{
- if (signal_pending(current))
- return;
-
- spin_unlock(&fc->lock);
- wait_event_interruptible(req->waitq, req->state == FUSE_REQ_FINISHED);
- spin_lock(&fc->lock);
-}
-
-static void queue_interrupt(struct fuse_conn *fc, struct fuse_req *req)
+static void queue_interrupt(struct fuse_iqueue *fiq, struct fuse_req *req)
{
- list_add_tail(&req->intr_entry, &fc->interrupts);
- wake_up(&fc->waitq);
- kill_fasync(&fc->fasync, SIGIO, POLL_IN);
+ spin_lock(&fiq->waitq.lock);
+ if (list_empty(&req->intr_entry)) {
+ list_add_tail(&req->intr_entry, &fiq->interrupts);
+ wake_up_locked(&fiq->waitq);
+ }
+ spin_unlock(&fiq->waitq.lock);
+ kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
}
static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
-__releases(fc->lock)
-__acquires(fc->lock)
{
+ struct fuse_iqueue *fiq = &fc->iq;
+ int err;
+
if (!fc->no_interrupt) {
/* Any signal may interrupt this */
- wait_answer_interruptible(fc, req);
-
- if (req->aborted)
- goto aborted;
- if (req->state == FUSE_REQ_FINISHED)
+ err = wait_event_interruptible(req->waitq,
+ test_bit(FR_FINISHED, &req->flags));
+ if (!err)
return;
- req->interrupted = 1;
- if (req->state == FUSE_REQ_SENT)
- queue_interrupt(fc, req);
+ set_bit(FR_INTERRUPTED, &req->flags);
+ /* matches barrier in fuse_dev_do_read() */
+ smp_mb__after_atomic();
+ if (test_bit(FR_SENT, &req->flags))
+ queue_interrupt(fiq, req);
}
- if (!req->force) {
+ if (!test_bit(FR_FORCE, &req->flags)) {
sigset_t oldset;
/* Only fatal signals may interrupt this */
block_sigs(&oldset);
- wait_answer_interruptible(fc, req);
+ err = wait_event_interruptible(req->waitq,
+ test_bit(FR_FINISHED, &req->flags));
restore_sigs(&oldset);
- if (req->aborted)
- goto aborted;
- if (req->state == FUSE_REQ_FINISHED)
+ if (!err)
return;
+ spin_lock(&fiq->waitq.lock);
/* Request is not yet in userspace, bail out */
- if (req->state == FUSE_REQ_PENDING) {
+ if (test_bit(FR_PENDING, &req->flags)) {
list_del(&req->list);
+ spin_unlock(&fiq->waitq.lock);
__fuse_put_request(req);
req->out.h.error = -EINTR;
return;
}
+ spin_unlock(&fiq->waitq.lock);
}
/*
* Either request is already in userspace, or it was forced.
* Wait it out.
*/
- spin_unlock(&fc->lock);
- wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
- spin_lock(&fc->lock);
-
- if (!req->aborted)
- return;
-
- aborted:
- BUG_ON(req->state != FUSE_REQ_FINISHED);
- if (req->locked) {
- /* This is uninterruptible sleep, because data is
- being copied to/from the buffers of req. During
- locked state, there mustn't be any filesystem
- operation (e.g. page fault), since that could lead
- to deadlock */
- spin_unlock(&fc->lock);
- wait_event(req->waitq, !req->locked);
- spin_lock(&fc->lock);
- }
+ wait_event(req->waitq, test_bit(FR_FINISHED, &req->flags));
}
static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
{
- BUG_ON(req->background);
- spin_lock(&fc->lock);
- if (!fc->connected)
+ struct fuse_iqueue *fiq = &fc->iq;
+
+ BUG_ON(test_bit(FR_BACKGROUND, &req->flags));
+ spin_lock(&fiq->waitq.lock);
+ if (!fiq->connected) {
+ spin_unlock(&fiq->waitq.lock);
req->out.h.error = -ENOTCONN;
- else if (fc->conn_error)
- req->out.h.error = -ECONNREFUSED;
- else {
- req->in.h.unique = fuse_get_unique(fc);
- queue_request(fc, req);
+ } else {
+ req->in.h.unique = fuse_get_unique(fiq);
+ queue_request(fiq, req);
/* acquire extra reference, since request is still needed
after request_end() */
__fuse_get_request(req);
+ spin_unlock(&fiq->waitq.lock);
request_wait_answer(fc, req);
+ /* Pairs with smp_wmb() in request_end() */
+ smp_rmb();
}
- spin_unlock(&fc->lock);
}
void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
{
- req->isreply = 1;
+ __set_bit(FR_ISREPLY, &req->flags);
+ if (!test_bit(FR_WAITING, &req->flags)) {
+ __set_bit(FR_WAITING, &req->flags);
+ atomic_inc(&fc->num_waiting);
+ }
__fuse_request_send(fc, req);
}
EXPORT_SYMBOL_GPL(fuse_request_send);
@@ -586,10 +575,20 @@ ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args)
return ret;
}
-static void fuse_request_send_nowait_locked(struct fuse_conn *fc,
- struct fuse_req *req)
+/*
+ * Called under fc->lock
+ *
+ * fc->connected must have been checked previously
+ */
+void fuse_request_send_background_locked(struct fuse_conn *fc,
+ struct fuse_req *req)
{
- BUG_ON(!req->background);
+ BUG_ON(!test_bit(FR_BACKGROUND, &req->flags));
+ if (!test_bit(FR_WAITING, &req->flags)) {
+ __set_bit(FR_WAITING, &req->flags);
+ atomic_inc(&fc->num_waiting);
+ }
+ __set_bit(FR_ISREPLY, &req->flags);
fc->num_background++;
if (fc->num_background == fc->max_background)
fc->blocked = 1;
@@ -602,54 +601,40 @@ static void fuse_request_send_nowait_locked(struct fuse_conn *fc,
flush_bg_queue(fc);
}
-static void fuse_request_send_nowait(struct fuse_conn *fc, struct fuse_req *req)
+void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req)
{
+ BUG_ON(!req->end);
spin_lock(&fc->lock);
if (fc->connected) {
- fuse_request_send_nowait_locked(fc, req);
+ fuse_request_send_background_locked(fc, req);
spin_unlock(&fc->lock);
} else {
+ spin_unlock(&fc->lock);
req->out.h.error = -ENOTCONN;
- request_end(fc, req);
+ req->end(fc, req);
+ fuse_put_request(fc, req);
}
}
-
-void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req)
-{
- req->isreply = 1;
- fuse_request_send_nowait(fc, req);
-}
EXPORT_SYMBOL_GPL(fuse_request_send_background);
static int fuse_request_send_notify_reply(struct fuse_conn *fc,
struct fuse_req *req, u64 unique)
{
int err = -ENODEV;
+ struct fuse_iqueue *fiq = &fc->iq;
- req->isreply = 0;
+ __clear_bit(FR_ISREPLY, &req->flags);
req->in.h.unique = unique;
- spin_lock(&fc->lock);
- if (fc->connected) {
- queue_request(fc, req);
+ spin_lock(&fiq->waitq.lock);
+ if (fiq->connected) {
+ queue_request(fiq, req);
err = 0;
}
- spin_unlock(&fc->lock);
+ spin_unlock(&fiq->waitq.lock);
return err;
}
-/*
- * Called under fc->lock
- *
- * fc->connected must have been checked previously
- */
-void fuse_request_send_background_locked(struct fuse_conn *fc,
- struct fuse_req *req)
-{
- req->isreply = 1;
- fuse_request_send_nowait_locked(fc, req);
-}
-
void fuse_force_forget(struct file *file, u64 nodeid)
{
struct inode *inode = file_inode(file);
@@ -665,7 +650,7 @@ void fuse_force_forget(struct file *file, u64 nodeid)
req->in.numargs = 1;
req->in.args[0].size = sizeof(inarg);
req->in.args[0].value = &inarg;
- req->isreply = 0;
+ __clear_bit(FR_ISREPLY, &req->flags);
__fuse_request_send(fc, req);
/* ignore errors */
fuse_put_request(fc, req);
@@ -676,38 +661,39 @@ void fuse_force_forget(struct file *file, u64 nodeid)
* anything that could cause a page-fault. If the request was already
* aborted bail out.
*/
-static int lock_request(struct fuse_conn *fc, struct fuse_req *req)
+static int lock_request(struct fuse_req *req)
{
int err = 0;
if (req) {
- spin_lock(&fc->lock);
- if (req->aborted)
+ spin_lock(&req->waitq.lock);
+ if (test_bit(FR_ABORTED, &req->flags))
err = -ENOENT;
else
- req->locked = 1;
- spin_unlock(&fc->lock);
+ set_bit(FR_LOCKED, &req->flags);
+ spin_unlock(&req->waitq.lock);
}
return err;
}
/*
- * Unlock request. If it was aborted during being locked, the
- * requester thread is currently waiting for it to be unlocked, so
- * wake it up.
+ * Unlock request. If it was aborted while locked, caller is responsible
+ * for unlocking and ending the request.
*/
-static void unlock_request(struct fuse_conn *fc, struct fuse_req *req)
+static int unlock_request(struct fuse_req *req)
{
+ int err = 0;
if (req) {
- spin_lock(&fc->lock);
- req->locked = 0;
- if (req->aborted)
- wake_up(&req->waitq);
- spin_unlock(&fc->lock);
+ spin_lock(&req->waitq.lock);
+ if (test_bit(FR_ABORTED, &req->flags))
+ err = -ENOENT;
+ else
+ clear_bit(FR_LOCKED, &req->flags);
+ spin_unlock(&req->waitq.lock);
}
+ return err;
}
struct fuse_copy_state {
- struct fuse_conn *fc;
int write;
struct fuse_req *req;
struct iov_iter *iter;
@@ -721,13 +707,10 @@ struct fuse_copy_state {
unsigned move_pages:1;
};
-static void fuse_copy_init(struct fuse_copy_state *cs,
- struct fuse_conn *fc,
- int write,
+static void fuse_copy_init(struct fuse_copy_state *cs, int write,
struct iov_iter *iter)
{
memset(cs, 0, sizeof(*cs));
- cs->fc = fc;
cs->write = write;
cs->iter = iter;
}
@@ -760,7 +743,10 @@ static int fuse_copy_fill(struct fuse_copy_state *cs)
struct page *page;
int err;
- unlock_request(cs->fc, cs->req);
+ err = unlock_request(cs->req);
+ if (err)
+ return err;
+
fuse_copy_finish(cs);
if (cs->pipebufs) {
struct pipe_buffer *buf = cs->pipebufs;
@@ -809,7 +795,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs)
iov_iter_advance(cs->iter, err);
}
- return lock_request(cs->fc, cs->req);
+ return lock_request(cs->req);
}
/* Do as much copy to/from userspace buffer as we can */
@@ -860,7 +846,10 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
struct page *newpage;
struct pipe_buffer *buf = cs->pipebufs;
- unlock_request(cs->fc, cs->req);
+ err = unlock_request(cs->req);
+ if (err)
+ return err;
+
fuse_copy_finish(cs);
err = buf->ops->confirm(cs->pipe, buf);
@@ -914,12 +903,12 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
lru_cache_add_file(newpage);
err = 0;
- spin_lock(&cs->fc->lock);
- if (cs->req->aborted)
+ spin_lock(&cs->req->waitq.lock);
+ if (test_bit(FR_ABORTED, &cs->req->flags))
err = -ENOENT;
else
*pagep = newpage;
- spin_unlock(&cs->fc->lock);
+ spin_unlock(&cs->req->waitq.lock);
if (err) {
unlock_page(newpage);
@@ -939,7 +928,7 @@ out_fallback:
cs->pg = buf->page;
cs->offset = buf->offset;
- err = lock_request(cs->fc, cs->req);
+ err = lock_request(cs->req);
if (err)
return err;
@@ -950,11 +939,15 @@ static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
unsigned offset, unsigned count)
{
struct pipe_buffer *buf;
+ int err;
if (cs->nr_segs == cs->pipe->buffers)
return -EIO;
- unlock_request(cs->fc, cs->req);
+ err = unlock_request(cs->req);
+ if (err)
+ return err;
+
fuse_copy_finish(cs);
buf = cs->pipebufs;
@@ -1065,36 +1058,15 @@ static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
return err;
}
-static int forget_pending(struct fuse_conn *fc)
+static int forget_pending(struct fuse_iqueue *fiq)
{
- return fc->forget_list_head.next != NULL;
+ return fiq->forget_list_head.next != NULL;
}
-static int request_pending(struct fuse_conn *fc)
+static int request_pending(struct fuse_iqueue *fiq)
{
- return !list_empty(&fc->pending) || !list_empty(&fc->interrupts) ||
- forget_pending(fc);
-}
-
-/* Wait until a request is available on the pending list */
-static void request_wait(struct fuse_conn *fc)
-__releases(fc->lock)
-__acquires(fc->lock)
-{
- DECLARE_WAITQUEUE(wait, current);
-
- add_wait_queue_exclusive(&fc->waitq, &wait);
- while (fc->connected && !request_pending(fc)) {
- set_current_state(TASK_INTERRUPTIBLE);
- if (signal_pending(current))
- break;
-
- spin_unlock(&fc->lock);
- schedule();
- spin_lock(&fc->lock);
- }
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&fc->waitq, &wait);
+ return !list_empty(&fiq->pending) || !list_empty(&fiq->interrupts) ||
+ forget_pending(fiq);
}
/*
@@ -1103,11 +1075,12 @@ __acquires(fc->lock)
* Unlike other requests this is assembled on demand, without a need
* to allocate a separate fuse_req structure.
*
- * Called with fc->lock held, releases it
+ * Called with fiq->waitq.lock held, releases it
*/
-static int fuse_read_interrupt(struct fuse_conn *fc, struct fuse_copy_state *cs,
+static int fuse_read_interrupt(struct fuse_iqueue *fiq,
+ struct fuse_copy_state *cs,
size_t nbytes, struct fuse_req *req)
-__releases(fc->lock)
+__releases(fiq->waitq.lock)
{
struct fuse_in_header ih;
struct fuse_interrupt_in arg;
@@ -1115,7 +1088,7 @@ __releases(fc->lock)
int err;
list_del_init(&req->intr_entry);
- req->intr_unique = fuse_get_unique(fc);
+ req->intr_unique = fuse_get_unique(fiq);
memset(&ih, 0, sizeof(ih));
memset(&arg, 0, sizeof(arg));
ih.len = reqsize;
@@ -1123,7 +1096,7 @@ __releases(fc->lock)
ih.unique = req->intr_unique;
arg.unique = req->in.h.unique;
- spin_unlock(&fc->lock);
+ spin_unlock(&fiq->waitq.lock);
if (nbytes < reqsize)
return -EINVAL;
@@ -1135,21 +1108,21 @@ __releases(fc->lock)
return err ? err : reqsize;
}
-static struct fuse_forget_link *dequeue_forget(struct fuse_conn *fc,
+static struct fuse_forget_link *dequeue_forget(struct fuse_iqueue *fiq,
unsigned max,
unsigned *countp)
{
- struct fuse_forget_link *head = fc->forget_list_head.next;
+ struct fuse_forget_link *head = fiq->forget_list_head.next;
struct fuse_forget_link **newhead = &head;
unsigned count;
for (count = 0; *newhead != NULL && count < max; count++)
newhead = &(*newhead)->next;
- fc->forget_list_head.next = *newhead;
+ fiq->forget_list_head.next = *newhead;
*newhead = NULL;
- if (fc->forget_list_head.next == NULL)
- fc->forget_list_tail = &fc->forget_list_head;
+ if (fiq->forget_list_head.next == NULL)
+ fiq->forget_list_tail = &fiq->forget_list_head;
if (countp != NULL)
*countp = count;
@@ -1157,24 +1130,24 @@ static struct fuse_forget_link *dequeue_forget(struct fuse_conn *fc,
return head;
}
-static int fuse_read_single_forget(struct fuse_conn *fc,
+static int fuse_read_single_forget(struct fuse_iqueue *fiq,
struct fuse_copy_state *cs,
size_t nbytes)
-__releases(fc->lock)
+__releases(fiq->waitq.lock)
{
int err;
- struct fuse_forget_link *forget = dequeue_forget(fc, 1, NULL);
+ struct fuse_forget_link *forget = dequeue_forget(fiq, 1, NULL);
struct fuse_forget_in arg = {
.nlookup = forget->forget_one.nlookup,
};
struct fuse_in_header ih = {
.opcode = FUSE_FORGET,
.nodeid = forget->forget_one.nodeid,
- .unique = fuse_get_unique(fc),
+ .unique = fuse_get_unique(fiq),
.len = sizeof(ih) + sizeof(arg),
};
- spin_unlock(&fc->lock);
+ spin_unlock(&fiq->waitq.lock);
kfree(forget);
if (nbytes < ih.len)
return -EINVAL;
@@ -1190,9 +1163,9 @@ __releases(fc->lock)
return ih.len;
}
-static int fuse_read_batch_forget(struct fuse_conn *fc,
+static int fuse_read_batch_forget(struct fuse_iqueue *fiq,
struct fuse_copy_state *cs, size_t nbytes)
-__releases(fc->lock)
+__releases(fiq->waitq.lock)
{
int err;
unsigned max_forgets;
@@ -1201,18 +1174,18 @@ __releases(fc->lock)
struct fuse_batch_forget_in arg = { .count = 0 };
struct fuse_in_header ih = {
.opcode = FUSE_BATCH_FORGET,
- .unique = fuse_get_unique(fc),
+ .unique = fuse_get_unique(fiq),
.len = sizeof(ih) + sizeof(arg),
};
if (nbytes < ih.len) {
- spin_unlock(&fc->lock);
+ spin_unlock(&fiq->waitq.lock);
return -EINVAL;
}
max_forgets = (nbytes - ih.len) / sizeof(struct fuse_forget_one);
- head = dequeue_forget(fc, max_forgets, &count);
- spin_unlock(&fc->lock);
+ head = dequeue_forget(fiq, max_forgets, &count);
+ spin_unlock(&fiq->waitq.lock);
arg.count = count;
ih.len += count * sizeof(struct fuse_forget_one);
@@ -1239,14 +1212,15 @@ __releases(fc->lock)
return ih.len;
}
-static int fuse_read_forget(struct fuse_conn *fc, struct fuse_copy_state *cs,
+static int fuse_read_forget(struct fuse_conn *fc, struct fuse_iqueue *fiq,
+ struct fuse_copy_state *cs,
size_t nbytes)
-__releases(fc->lock)
+__releases(fiq->waitq.lock)
{
- if (fc->minor < 16 || fc->forget_list_head.next->next == NULL)
- return fuse_read_single_forget(fc, cs, nbytes);
+ if (fc->minor < 16 || fiq->forget_list_head.next->next == NULL)
+ return fuse_read_single_forget(fiq, cs, nbytes);
else
- return fuse_read_batch_forget(fc, cs, nbytes);
+ return fuse_read_batch_forget(fiq, cs, nbytes);
}
/*
@@ -1258,46 +1232,51 @@ __releases(fc->lock)
* request_end(). Otherwise add it to the processing list, and set
* the 'sent' flag.
*/
-static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file,
+static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
struct fuse_copy_state *cs, size_t nbytes)
{
- int err;
+ ssize_t err;
+ struct fuse_conn *fc = fud->fc;
+ struct fuse_iqueue *fiq = &fc->iq;
+ struct fuse_pqueue *fpq = &fud->pq;
struct fuse_req *req;
struct fuse_in *in;
unsigned reqsize;
restart:
- spin_lock(&fc->lock);
+ spin_lock(&fiq->waitq.lock);
err = -EAGAIN;
- if ((file->f_flags & O_NONBLOCK) && fc->connected &&
- !request_pending(fc))
+ if ((file->f_flags & O_NONBLOCK) && fiq->connected &&
+ !request_pending(fiq))
goto err_unlock;
- request_wait(fc);
- err = -ENODEV;
- if (!fc->connected)
+ err = wait_event_interruptible_exclusive_locked(fiq->waitq,
+ !fiq->connected || request_pending(fiq));
+ if (err)
goto err_unlock;
- err = -ERESTARTSYS;
- if (!request_pending(fc))
+
+ err = -ENODEV;
+ if (!fiq->connected)
goto err_unlock;
- if (!list_empty(&fc->interrupts)) {
- req = list_entry(fc->interrupts.next, struct fuse_req,
+ if (!list_empty(&fiq->interrupts)) {
+ req = list_entry(fiq->interrupts.next, struct fuse_req,
intr_entry);
- return fuse_read_interrupt(fc, cs, nbytes, req);
+ return fuse_read_interrupt(fiq, cs, nbytes, req);
}
- if (forget_pending(fc)) {
- if (list_empty(&fc->pending) || fc->forget_batch-- > 0)
- return fuse_read_forget(fc, cs, nbytes);
+ if (forget_pending(fiq)) {
+ if (list_empty(&fiq->pending) || fiq->forget_batch-- > 0)
+ return fuse_read_forget(fc, fiq, cs, nbytes);
- if (fc->forget_batch <= -8)
- fc->forget_batch = 16;
+ if (fiq->forget_batch <= -8)
+ fiq->forget_batch = 16;
}
- req = list_entry(fc->pending.next, struct fuse_req, list);
- req->state = FUSE_REQ_READING;
- list_move(&req->list, &fc->io);
+ req = list_entry(fiq->pending.next, struct fuse_req, list);
+ clear_bit(FR_PENDING, &req->flags);
+ list_del_init(&req->list);
+ spin_unlock(&fiq->waitq.lock);
in = &req->in;
reqsize = in->h.len;
@@ -1310,37 +1289,48 @@ static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file,
request_end(fc, req);
goto restart;
}
- spin_unlock(&fc->lock);
+ spin_lock(&fpq->lock);
+ list_add(&req->list, &fpq->io);
+ spin_unlock(&fpq->lock);
cs->req = req;
err = fuse_copy_one(cs, &in->h, sizeof(in->h));
if (!err)
err = fuse_copy_args(cs, in->numargs, in->argpages,
(struct fuse_arg *) in->args, 0);
fuse_copy_finish(cs);
- spin_lock(&fc->lock);
- req->locked = 0;
- if (req->aborted) {
- request_end(fc, req);
- return -ENODEV;
+ spin_lock(&fpq->lock);
+ clear_bit(FR_LOCKED, &req->flags);
+ if (!fpq->connected) {
+ err = -ENODEV;
+ goto out_end;
}
if (err) {
req->out.h.error = -EIO;
- request_end(fc, req);
- return err;
+ goto out_end;
}
- if (!req->isreply)
- request_end(fc, req);
- else {
- req->state = FUSE_REQ_SENT;
- list_move_tail(&req->list, &fc->processing);
- if (req->interrupted)
- queue_interrupt(fc, req);
- spin_unlock(&fc->lock);
+ if (!test_bit(FR_ISREPLY, &req->flags)) {
+ err = reqsize;
+ goto out_end;
}
+ list_move_tail(&req->list, &fpq->processing);
+ spin_unlock(&fpq->lock);
+ set_bit(FR_SENT, &req->flags);
+ /* matches barrier in request_wait_answer() */
+ smp_mb__after_atomic();
+ if (test_bit(FR_INTERRUPTED, &req->flags))
+ queue_interrupt(fiq, req);
+
return reqsize;
+out_end:
+ if (!test_bit(FR_PRIVATE, &req->flags))
+ list_del_init(&req->list);
+ spin_unlock(&fpq->lock);
+ request_end(fc, req);
+ return err;
+
err_unlock:
- spin_unlock(&fc->lock);
+ spin_unlock(&fiq->waitq.lock);
return err;
}
@@ -1359,16 +1349,17 @@ 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))
return -EINVAL;
- fuse_copy_init(&cs, fc, 1, 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, file, &cs, iov_iter_count(to));
}
static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
@@ -1380,18 +1371,19 @@ 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);
if (!bufs)
return -ENOMEM;
- fuse_copy_init(&cs, fc, 1, NULL);
+ 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, in, &cs, len);
if (ret < 0)
goto out;
@@ -1830,11 +1822,11 @@ static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code,
}
/* Look up request on processing list by unique ID */
-static struct fuse_req *request_find(struct fuse_conn *fc, u64 unique)
+static struct fuse_req *request_find(struct fuse_pqueue *fpq, u64 unique)
{
struct fuse_req *req;
- list_for_each_entry(req, &fc->processing, list) {
+ list_for_each_entry(req, &fpq->processing, list) {
if (req->in.h.unique == unique || req->intr_unique == unique)
return req;
}
@@ -1871,10 +1863,12 @@ static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
* it from the list and copy the rest of the buffer to the request.
* The request is finished by calling request_end()
*/
-static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
+static ssize_t fuse_dev_do_write(struct fuse_dev *fud,
struct fuse_copy_state *cs, size_t nbytes)
{
int err;
+ struct fuse_conn *fc = fud->fc;
+ struct fuse_pqueue *fpq = &fud->pq;
struct fuse_req *req;
struct fuse_out_header oh;
@@ -1902,63 +1896,60 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
if (oh.error <= -1000 || oh.error > 0)
goto err_finish;
- spin_lock(&fc->lock);
+ spin_lock(&fpq->lock);
err = -ENOENT;
- if (!fc->connected)
- goto err_unlock;
+ if (!fpq->connected)
+ goto err_unlock_pq;
- req = request_find(fc, oh.unique);
+ req = request_find(fpq, oh.unique);
if (!req)
- goto err_unlock;
+ goto err_unlock_pq;
- if (req->aborted) {
- spin_unlock(&fc->lock);
- fuse_copy_finish(cs);
- spin_lock(&fc->lock);
- request_end(fc, req);
- return -ENOENT;
- }
/* Is it an interrupt reply? */
if (req->intr_unique == oh.unique) {
+ spin_unlock(&fpq->lock);
+
err = -EINVAL;
if (nbytes != sizeof(struct fuse_out_header))
- goto err_unlock;
+ goto err_finish;
if (oh.error == -ENOSYS)
fc->no_interrupt = 1;
else if (oh.error == -EAGAIN)
- queue_interrupt(fc, req);
+ queue_interrupt(&fc->iq, req);
- spin_unlock(&fc->lock);
fuse_copy_finish(cs);
return nbytes;
}
- req->state = FUSE_REQ_WRITING;
- list_move(&req->list, &fc->io);
+ clear_bit(FR_SENT, &req->flags);
+ list_move(&req->list, &fpq->io);
req->out.h = oh;
- req->locked = 1;
+ set_bit(FR_LOCKED, &req->flags);
+ spin_unlock(&fpq->lock);
cs->req = req;
if (!req->out.page_replace)
cs->move_pages = 0;
- spin_unlock(&fc->lock);
err = copy_out_args(cs, &req->out, nbytes);
fuse_copy_finish(cs);
- spin_lock(&fc->lock);
- req->locked = 0;
- if (!err) {
- if (req->aborted)
- err = -ENOENT;
- } else if (!req->aborted)
+ spin_lock(&fpq->lock);
+ clear_bit(FR_LOCKED, &req->flags);
+ if (!fpq->connected)
+ err = -ENOENT;
+ else if (err)
req->out.h.error = -EIO;
+ if (!test_bit(FR_PRIVATE, &req->flags))
+ list_del_init(&req->list);
+ spin_unlock(&fpq->lock);
+
request_end(fc, req);
return err ? err : nbytes;
- err_unlock:
- spin_unlock(&fc->lock);
+ err_unlock_pq:
+ spin_unlock(&fpq->lock);
err_finish:
fuse_copy_finish(cs);
return err;
@@ -1967,16 +1958,17 @@ 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))
return -EINVAL;
- fuse_copy_init(&cs, fc, 0, from);
+ fuse_copy_init(&cs, 0, from);
- return fuse_dev_do_write(fc, &cs, iov_iter_count(from));
+ return fuse_dev_do_write(fud, &cs, iov_iter_count(from));
}
static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
@@ -1987,12 +1979,12 @@ 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);
@@ -2039,7 +2031,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
}
pipe_unlock(pipe);
- fuse_copy_init(&cs, fc, 0, NULL);
+ fuse_copy_init(&cs, 0, NULL);
cs.pipebufs = bufs;
cs.nr_segs = nbuf;
cs.pipe = pipe;
@@ -2047,7 +2039,7 @@ 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, &cs, len);
for (idx = 0; idx < nbuf; idx++) {
struct pipe_buffer *buf = &bufs[idx];
@@ -2061,18 +2053,21 @@ out:
static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
{
unsigned mask = POLLOUT | POLLWRNORM;
- struct fuse_conn *fc = fuse_get_conn(file);
- if (!fc)
+ struct fuse_iqueue *fiq;
+ struct fuse_dev *fud = fuse_get_dev(file);
+
+ if (!fud)
return POLLERR;
- poll_wait(file, &fc->waitq, wait);
+ fiq = &fud->fc->iq;
+ poll_wait(file, &fiq->waitq, wait);
- spin_lock(&fc->lock);
- if (!fc->connected)
+ spin_lock(&fiq->waitq.lock);
+ if (!fiq->connected)
mask = POLLERR;
- else if (request_pending(fc))
+ else if (request_pending(fiq))
mask |= POLLIN | POLLRDNORM;
- spin_unlock(&fc->lock);
+ spin_unlock(&fiq->waitq.lock);
return mask;
}
@@ -2083,67 +2078,18 @@ static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
* This function releases and reacquires fc->lock
*/
static void end_requests(struct fuse_conn *fc, struct list_head *head)
-__releases(fc->lock)
-__acquires(fc->lock)
{
while (!list_empty(head)) {
struct fuse_req *req;
req = list_entry(head->next, struct fuse_req, list);
req->out.h.error = -ECONNABORTED;
- request_end(fc, req);
- spin_lock(&fc->lock);
- }
-}
-
-/*
- * Abort requests under I/O
- *
- * The requests are set to aborted and finished, and the request
- * waiter is woken up. This will make request_wait_answer() wait
- * until the request is unlocked and then return.
- *
- * If the request is asynchronous, then the end function needs to be
- * called after waiting for the request to be unlocked (if it was
- * locked).
- */
-static void end_io_requests(struct fuse_conn *fc)
-__releases(fc->lock)
-__acquires(fc->lock)
-{
- while (!list_empty(&fc->io)) {
- struct fuse_req *req =
- list_entry(fc->io.next, struct fuse_req, list);
- void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
-
- req->aborted = 1;
- req->out.h.error = -ECONNABORTED;
- req->state = FUSE_REQ_FINISHED;
+ clear_bit(FR_PENDING, &req->flags);
+ clear_bit(FR_SENT, &req->flags);
list_del_init(&req->list);
- wake_up(&req->waitq);
- if (end) {
- req->end = NULL;
- __fuse_get_request(req);
- spin_unlock(&fc->lock);
- wait_event(req->waitq, !req->locked);
- end(fc, req);
- fuse_put_request(fc, req);
- spin_lock(&fc->lock);
- }
+ request_end(fc, req);
}
}
-static void end_queued_requests(struct fuse_conn *fc)
-__releases(fc->lock)
-__acquires(fc->lock)
-{
- fc->max_background = UINT_MAX;
- flush_bg_queue(fc);
- end_requests(fc, &fc->pending);
- end_requests(fc, &fc->processing);
- while (forget_pending(fc))
- kfree(dequeue_forget(fc, 1, NULL));
-}
-
static void end_polls(struct fuse_conn *fc)
{
struct rb_node *p;
@@ -2162,67 +2108,164 @@ static void end_polls(struct fuse_conn *fc)
/*
* Abort all requests.
*
- * Emergency exit in case of a malicious or accidental deadlock, or
- * just a hung filesystem.
- *
- * The same effect is usually achievable through killing the
- * filesystem daemon and all users of the filesystem. The exception
- * is the combination of an asynchronous request and the tricky
- * deadlock (see Documentation/filesystems/fuse.txt).
+ * Emergency exit in case of a malicious or accidental deadlock, or just a hung
+ * filesystem.
*
- * During the aborting, progression of requests from the pending and
- * processing lists onto the io list, and progression of new requests
- * onto the pending list is prevented by req->connected being false.
+ * The same effect is usually achievable through killing the filesystem daemon
+ * and all users of the filesystem. The exception is the combination of an
+ * asynchronous request and the tricky deadlock (see
+ * Documentation/filesystems/fuse.txt).
*
- * Progression of requests under I/O to the processing list is
- * prevented by the req->aborted flag being true for these requests.
- * For this reason requests on the io list must be aborted first.
+ * Aborting requests under I/O goes as follows: 1: Separate out unlocked
+ * requests, they should be finished off immediately. Locked requests will be
+ * finished after unlock; see unlock_request(). 2: Finish off the unlocked
+ * requests. It is possible that some request will finish before we can. This
+ * is OK, the request will in that case be removed from the list before we touch
+ * it.
*/
void fuse_abort_conn(struct fuse_conn *fc)
{
+ struct fuse_iqueue *fiq = &fc->iq;
+
spin_lock(&fc->lock);
if (fc->connected) {
+ struct fuse_dev *fud;
+ struct fuse_req *req, *next;
+ LIST_HEAD(to_end1);
+ LIST_HEAD(to_end2);
+
fc->connected = 0;
fc->blocked = 0;
fuse_set_initialized(fc);
- end_io_requests(fc);
- end_queued_requests(fc);
+ list_for_each_entry(fud, &fc->devices, entry) {
+ struct fuse_pqueue *fpq = &fud->pq;
+
+ spin_lock(&fpq->lock);
+ fpq->connected = 0;
+ list_for_each_entry_safe(req, next, &fpq->io, list) {
+ req->out.h.error = -ECONNABORTED;
+ spin_lock(&req->waitq.lock);
+ set_bit(FR_ABORTED, &req->flags);
+ if (!test_bit(FR_LOCKED, &req->flags)) {
+ set_bit(FR_PRIVATE, &req->flags);
+ list_move(&req->list, &to_end1);
+ }
+ spin_unlock(&req->waitq.lock);
+ }
+ list_splice_init(&fpq->processing, &to_end2);
+ spin_unlock(&fpq->lock);
+ }
+ fc->max_background = UINT_MAX;
+ flush_bg_queue(fc);
+
+ spin_lock(&fiq->waitq.lock);
+ fiq->connected = 0;
+ list_splice_init(&fiq->pending, &to_end2);
+ while (forget_pending(fiq))
+ kfree(dequeue_forget(fiq, 1, NULL));
+ wake_up_all_locked(&fiq->waitq);
+ spin_unlock(&fiq->waitq.lock);
+ kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
end_polls(fc);
- wake_up_all(&fc->waitq);
wake_up_all(&fc->blocked_waitq);
- kill_fasync(&fc->fasync, SIGIO, POLL_IN);
+ spin_unlock(&fc->lock);
+
+ while (!list_empty(&to_end1)) {
+ req = list_first_entry(&to_end1, struct fuse_req, list);
+ __fuse_get_request(req);
+ list_del_init(&req->list);
+ request_end(fc, req);
+ }
+ end_requests(fc, &to_end2);
+ } else {
+ spin_unlock(&fc->lock);
}
- spin_unlock(&fc->lock);
}
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) {
- spin_lock(&fc->lock);
- fc->connected = 0;
- fc->blocked = 0;
- fuse_set_initialized(fc);
- end_queued_requests(fc);
- end_polls(fc);
- wake_up_all(&fc->blocked_waitq);
- spin_unlock(&fc->lock);
- fuse_conn_put(fc);
- }
+ struct fuse_dev *fud = fuse_get_dev(file);
+
+ if (fud) {
+ struct fuse_conn *fc = fud->fc;
+ struct fuse_pqueue *fpq = &fud->pq;
+ WARN_ON(!list_empty(&fpq->io));
+ end_requests(fc, &fpq->processing);
+ /* Are we the last open device? */
+ if (atomic_dec_and_test(&fc->dev_count)) {
+ WARN_ON(fc->iq.fasync != NULL);
+ fuse_abort_conn(fc);
+ }
+ fuse_dev_free(fud);
+ }
return 0;
}
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->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;
+
+ fud = fuse_dev_alloc(fc);
+ if (!fud)
+ return -ENOMEM;
+
+ new->private_data = fud;
+ atomic_inc(&fc->dev_count);
+
+ return 0;
+}
+
+static long fuse_dev_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int err = -ENOTTY;
+
+ if (cmd == FUSE_DEV_IOC_CLONE) {
+ int oldfd;
+
+ err = -EFAULT;
+ if (!get_user(oldfd, (__u32 __user *) arg)) {
+ struct file *old = fget(oldfd);
+
+ err = -EINVAL;
+ if (old) {
+ struct fuse_dev *fud = NULL;
+
+ /*
+ * Check against file->f_op because CUSE
+ * uses the same ioctl handler.
+ */
+ if (old->f_op == file->f_op &&
+ old->f_cred->user_ns == file->f_cred->user_ns)
+ fud = fuse_get_dev(old);
+
+ if (fud) {
+ mutex_lock(&fuse_mutex);
+ err = fuse_device_clone(fud->fc, file);
+ mutex_unlock(&fuse_mutex);
+ }
+ fput(old);
+ }
+ }
+ }
+ return err;
}
const struct file_operations fuse_dev_operations = {
@@ -2236,6 +2279,8 @@ const struct file_operations fuse_dev_operations = {
.poll = fuse_dev_poll,
.release = fuse_dev_release,
.fasync = fuse_dev_fasync,
+ .unlocked_ioctl = fuse_dev_ioctl,
+ .compat_ioctl = fuse_dev_ioctl,
};
EXPORT_SYMBOL_GPL(fuse_dev_operations);