fuse: pqueue locking
Add a fpq->lock for protecting members of struct fuse_pqueue and FR_LOCKED
request flag.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 3e84300..32e0e74 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1291,7 +1291,9 @@
request_end(fc, req);
goto restart;
}
+ spin_lock(&fpq->lock);
list_add(&req->list, &fpq->io);
+ spin_unlock(&fpq->lock);
spin_unlock(&fc->lock);
cs->req = req;
err = fuse_copy_one(cs, &in->h, sizeof(in->h));
@@ -1300,6 +1302,7 @@
(struct fuse_arg *) in->args, 0);
fuse_copy_finish(cs);
spin_lock(&fc->lock);
+ spin_lock(&fpq->lock);
clear_bit(FR_LOCKED, &req->flags);
if (!fpq->connected) {
err = -ENODEV;
@@ -1314,6 +1317,7 @@
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();
@@ -1325,6 +1329,7 @@
out_end:
list_del_init(&req->list);
+ spin_unlock(&fpq->lock);
request_end(fc, req);
return err;
@@ -1893,16 +1898,19 @@
goto err_finish;
spin_lock(&fc->lock);
+ spin_lock(&fpq->lock);
err = -ENOENT;
if (!fpq->connected)
- goto err_unlock;
+ goto err_unlock_pq;
req = request_find(fpq, oh.unique);
if (!req)
- goto err_unlock;
+ goto err_unlock_pq;
/* 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;
@@ -1921,6 +1929,7 @@
list_move(&req->list, &fpq->io);
req->out.h = oh;
set_bit(FR_LOCKED, &req->flags);
+ spin_unlock(&fpq->lock);
cs->req = req;
if (!req->out.page_replace)
cs->move_pages = 0;
@@ -1930,16 +1939,20 @@
fuse_copy_finish(cs);
spin_lock(&fc->lock);
+ spin_lock(&fpq->lock);
clear_bit(FR_LOCKED, &req->flags);
if (!fpq->connected)
err = -ENOENT;
else if (err)
req->out.h.error = -EIO;
list_del_init(&req->list);
+ spin_unlock(&fpq->lock);
request_end(fc, req);
return err ? err : nbytes;
+ err_unlock_pq:
+ spin_unlock(&fpq->lock);
err_unlock:
spin_unlock(&fc->lock);
err_finish:
@@ -2130,6 +2143,7 @@
fc->connected = 0;
fc->blocked = 0;
fuse_set_initialized(fc);
+ spin_lock(&fpq->lock);
fpq->connected = 0;
list_for_each_entry_safe(req, next, &fpq->io, list) {
req->out.h.error = -ECONNABORTED;
@@ -2140,6 +2154,7 @@
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);
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 5897d89..ad3799e 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -405,6 +405,9 @@
/** Connection established */
unsigned connected;
+ /** Lock protecting accessess to members of this structure */
+ spinlock_t lock;
+
/** The list of requests being processed */
struct list_head processing;
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 88b9ca4..8373f59 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -580,6 +580,7 @@
static void fuse_pqueue_init(struct fuse_pqueue *fpq)
{
memset(fpq, 0, sizeof(struct fuse_pqueue));
+ spin_lock_init(&fpq->lock);
INIT_LIST_HEAD(&fpq->processing);
INIT_LIST_HEAD(&fpq->io);
fpq->connected = 1;