diff options
author | Vivek Goyal <vgoyal@redhat.com> | 2019-03-06 16:51:40 -0500 |
---|---|---|
committer | Miklos Szeredi <mszeredi@redhat.com> | 2019-09-12 08:59:41 -0400 |
commit | 0cd1eb9a4160a96e0ec9b93b2e7b489f449bf22d (patch) | |
tree | 54ff7b7366dafb376d6a94bed28a86358c6b2023 | |
parent | ae3aad77f46fbba56eff7141b2fc49870b60827e (diff) |
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>
-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) | |||
508 | */ | 508 | */ |
509 | fuse_conn_init(&cc->fc, file->f_cred->user_ns, &fuse_dev_fiq_ops, NULL); | 509 | fuse_conn_init(&cc->fc, file->f_cred->user_ns, &fuse_dev_fiq_ops, NULL); |
510 | 510 | ||
511 | fud = fuse_dev_alloc(&cc->fc); | 511 | fud = fuse_dev_alloc_install(&cc->fc); |
512 | if (!fud) { | 512 | if (!fud) { |
513 | kfree(cc); | 513 | kfree(cc); |
514 | return -ENOMEM; | 514 | 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) | |||
2203 | if (new->private_data) | 2203 | if (new->private_data) |
2204 | return -EINVAL; | 2204 | return -EINVAL; |
2205 | 2205 | ||
2206 | fud = fuse_dev_alloc(fc); | 2206 | fud = fuse_dev_alloc_install(fc); |
2207 | if (!fud) | 2207 | if (!fud) |
2208 | return -ENOMEM; | 2208 | return -ENOMEM; |
2209 | 2209 | ||
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, | |||
929 | */ | 929 | */ |
930 | void fuse_conn_put(struct fuse_conn *fc); | 930 | void fuse_conn_put(struct fuse_conn *fc); |
931 | 931 | ||
932 | struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc); | 932 | struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc); |
933 | struct fuse_dev *fuse_dev_alloc(void); | ||
934 | void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc); | ||
933 | void fuse_dev_free(struct fuse_dev *fud); | 935 | void fuse_dev_free(struct fuse_dev *fud); |
934 | void fuse_send_init(struct fuse_conn *fc); | 936 | void fuse_send_init(struct fuse_conn *fc); |
935 | 937 | ||
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) | |||
1045 | return 0; | 1045 | return 0; |
1046 | } | 1046 | } |
1047 | 1047 | ||
1048 | struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc) | 1048 | struct fuse_dev *fuse_dev_alloc(void) |
1049 | { | 1049 | { |
1050 | struct fuse_dev *fud; | 1050 | struct fuse_dev *fud; |
1051 | struct list_head *pq; | 1051 | struct list_head *pq; |
@@ -1061,16 +1061,33 @@ struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc) | |||
1061 | } | 1061 | } |
1062 | 1062 | ||
1063 | fud->pq.processing = pq; | 1063 | fud->pq.processing = pq; |
1064 | fud->fc = fuse_conn_get(fc); | ||
1065 | fuse_pqueue_init(&fud->pq); | 1064 | fuse_pqueue_init(&fud->pq); |
1066 | 1065 | ||
1066 | return fud; | ||
1067 | } | ||
1068 | EXPORT_SYMBOL_GPL(fuse_dev_alloc); | ||
1069 | |||
1070 | void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc) | ||
1071 | { | ||
1072 | fud->fc = fuse_conn_get(fc); | ||
1067 | spin_lock(&fc->lock); | 1073 | spin_lock(&fc->lock); |
1068 | list_add_tail(&fud->entry, &fc->devices); | 1074 | list_add_tail(&fud->entry, &fc->devices); |
1069 | spin_unlock(&fc->lock); | 1075 | spin_unlock(&fc->lock); |
1076 | } | ||
1077 | EXPORT_SYMBOL_GPL(fuse_dev_install); | ||
1070 | 1078 | ||
1079 | struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc) | ||
1080 | { | ||
1081 | struct fuse_dev *fud; | ||
1082 | |||
1083 | fud = fuse_dev_alloc(); | ||
1084 | if (!fud) | ||
1085 | return NULL; | ||
1086 | |||
1087 | fuse_dev_install(fud, fc); | ||
1071 | return fud; | 1088 | return fud; |
1072 | } | 1089 | } |
1073 | EXPORT_SYMBOL_GPL(fuse_dev_alloc); | 1090 | EXPORT_SYMBOL_GPL(fuse_dev_alloc_install); |
1074 | 1091 | ||
1075 | void fuse_dev_free(struct fuse_dev *fud) | 1092 | void fuse_dev_free(struct fuse_dev *fud) |
1076 | { | 1093 | { |
@@ -1132,7 +1149,7 @@ int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx) | |||
1132 | if (sb->s_user_ns != &init_user_ns) | 1149 | if (sb->s_user_ns != &init_user_ns) |
1133 | sb->s_xattr = fuse_no_acl_xattr_handlers; | 1150 | sb->s_xattr = fuse_no_acl_xattr_handlers; |
1134 | 1151 | ||
1135 | fud = fuse_dev_alloc(fc); | 1152 | fud = fuse_dev_alloc_install(fc); |
1136 | if (!fud) | 1153 | if (!fud) |
1137 | goto err; | 1154 | goto err; |
1138 | 1155 | ||