diff options
author | Vivek Goyal <vgoyal@redhat.com> | 2019-03-07 00:51:40 +0300 |
---|---|---|
committer | Miklos Szeredi <mszeredi@redhat.com> | 2019-09-12 15:59:41 +0300 |
commit | 0cd1eb9a4160a96e0ec9b93b2e7b489f449bf22d (patch) | |
tree | 54ff7b7366dafb376d6a94bed28a86358c6b2023 /fs | |
parent | ae3aad77f46fbba56eff7141b2fc49870b60827e (diff) | |
download | linux-0cd1eb9a4160a96e0ec9b93b2e7b489f449bf22d.tar.xz |
fuse: separate fuse device allocation and installation in fuse_conn
As of now fuse_dev_alloc() both allocates a fuse device and installs it in
fuse_conn list. fuse_dev_alloc() can fail if fuse_device allocation fails.
virtio-fs needs to initialize multiple fuse devices (one per virtio queue).
It initializes one fuse device as part of call to fuse_fill_super_common()
and rest of the devices are allocated and installed after that.
But, we can't afford to fail after calling fuse_fill_super_common() as we
don't have a way to undo all the actions done by fuse_fill_super_common().
So to avoid failures after the call to fuse_fill_super_common(),
pre-allocate all fuse devices early and install them into fuse connection
later.
This patch provides two separate helpers for fuse device allocation and
fuse device installation in fuse_conn.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/fuse/cuse.c | 2 | ||||
-rw-r--r-- | fs/fuse/dev.c | 2 | ||||
-rw-r--r-- | fs/fuse/fuse_i.h | 4 | ||||
-rw-r--r-- | fs/fuse/inode.c | 25 |
4 files changed, 26 insertions, 7 deletions
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c index 6a0de0ce4403..45762bb7a934 100644 --- a/fs/fuse/cuse.c +++ b/fs/fuse/cuse.c @@ -508,7 +508,7 @@ static int cuse_channel_open(struct inode *inode, struct file *file) */ fuse_conn_init(&cc->fc, file->f_cred->user_ns, &fuse_dev_fiq_ops, NULL); - fud = fuse_dev_alloc(&cc->fc); + fud = fuse_dev_alloc_install(&cc->fc); if (!fud) { kfree(cc); return -ENOMEM; diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index 358a01435058..b2e18861c59c 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -2203,7 +2203,7 @@ static int fuse_device_clone(struct fuse_conn *fc, struct file *new) if (new->private_data) return -EINVAL; - fud = fuse_dev_alloc(fc); + fud = fuse_dev_alloc_install(fc); if (!fud) return -ENOMEM; diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 8c13865955d4..242d47752e78 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -929,7 +929,9 @@ void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns, */ void fuse_conn_put(struct fuse_conn *fc); -struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc); +struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc); +struct fuse_dev *fuse_dev_alloc(void); +void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc); void fuse_dev_free(struct fuse_dev *fud); void fuse_send_init(struct fuse_conn *fc); diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 734fdd597c3e..6a0f31faaeaa 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -1045,7 +1045,7 @@ 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 *fuse_dev_alloc(void) { struct fuse_dev *fud; struct list_head *pq; @@ -1061,16 +1061,33 @@ struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc) } fud->pq.processing = pq; - fud->fc = fuse_conn_get(fc); fuse_pqueue_init(&fud->pq); + return fud; +} +EXPORT_SYMBOL_GPL(fuse_dev_alloc); + +void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc) +{ + fud->fc = fuse_conn_get(fc); spin_lock(&fc->lock); list_add_tail(&fud->entry, &fc->devices); spin_unlock(&fc->lock); +} +EXPORT_SYMBOL_GPL(fuse_dev_install); +struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc) +{ + struct fuse_dev *fud; + + fud = fuse_dev_alloc(); + if (!fud) + return NULL; + + fuse_dev_install(fud, fc); return fud; } -EXPORT_SYMBOL_GPL(fuse_dev_alloc); +EXPORT_SYMBOL_GPL(fuse_dev_alloc_install); void fuse_dev_free(struct fuse_dev *fud) { @@ -1132,7 +1149,7 @@ int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx) if (sb->s_user_ns != &init_user_ns) sb->s_xattr = fuse_no_acl_xattr_handlers; - fud = fuse_dev_alloc(fc); + fud = fuse_dev_alloc_install(fc); if (!fud) goto err; |