From 45a91cb1a4fd9bb0e53c95e3dc9185dd5b5ba245 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 1 Jul 2015 16:26:06 +0200 Subject: fuse: pqueue locking Add a fpq->lock for protecting members of struct fuse_pqueue and FR_LOCKED request flag. Signed-off-by: Miklos Szeredi Reviewed-by: Ashish Samant --- fs/fuse/dev.c | 19 +++++++++++++++++-- fs/fuse/fuse_i.h | 3 +++ fs/fuse/inode.c | 1 + 3 files changed, 21 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index 3e8430074070..32e0e74e8f4d 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -1291,7 +1291,9 @@ static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file, 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 @@ static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file, (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 @@ static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file, 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 @@ static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file, out_end: list_del_init(&req->list); + spin_unlock(&fpq->lock); request_end(fc, req); return err; @@ -1893,16 +1898,19 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc, 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 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc, 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 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc, 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 @@ void fuse_abort_conn(struct fuse_conn *fc) 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 @@ void fuse_abort_conn(struct fuse_conn *fc) 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 5897d89ea2ba..ad3799e57efd 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -405,6 +405,9 @@ struct fuse_pqueue { /** 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 88b9ca401623..8373f59dc2a8 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -580,6 +580,7 @@ static void fuse_iqueue_init(struct fuse_iqueue *fiq) 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; -- cgit v1.2.3-59-g8ed1b