From 3b8b487114c95ef6db5fef708ef69bfb5209014e Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 25 Jun 2012 11:38:56 +0400 Subject: [PATCH] ecryptfs: don't reinvent the wheels, please - use struct completion ... and keep the sodding requests on stack - they are small enough. Signed-off-by: Al Viro --- fs/ecryptfs/ecryptfs_kernel.h | 14 ------- fs/ecryptfs/kthread.c | 72 +++++++++++++---------------------- fs/ecryptfs/main.c | 5 --- 3 files changed, 26 insertions(+), 65 deletions(-) diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index 867b64c5d84f..989e034f02bd 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -550,20 +550,6 @@ extern struct kmem_cache *ecryptfs_key_record_cache; extern struct kmem_cache *ecryptfs_key_sig_cache; extern struct kmem_cache *ecryptfs_global_auth_tok_cache; extern struct kmem_cache *ecryptfs_key_tfm_cache; -extern struct kmem_cache *ecryptfs_open_req_cache; - -struct ecryptfs_open_req { -#define ECRYPTFS_REQ_PROCESSED 0x00000001 -#define ECRYPTFS_REQ_DROPPED 0x00000002 -#define ECRYPTFS_REQ_ZOMBIE 0x00000004 - u32 flags; - struct file **lower_file; - struct dentry *lower_dentry; - struct vfsmount *lower_mnt; - wait_queue_head_t wait; - struct mutex mux; - struct list_head kthread_ctl_list; -}; struct inode *ecryptfs_get_inode(struct inode *lower_inode, struct super_block *sb); diff --git a/fs/ecryptfs/kthread.c b/fs/ecryptfs/kthread.c index 0dbe58a8b172..c7d199dc7d24 100644 --- a/fs/ecryptfs/kthread.c +++ b/fs/ecryptfs/kthread.c @@ -27,7 +27,13 @@ #include #include "ecryptfs_kernel.h" -struct kmem_cache *ecryptfs_open_req_cache; +struct ecryptfs_open_req { + struct file **lower_file; + struct dentry *lower_dentry; + struct vfsmount *lower_mnt; + struct completion done; + struct list_head kthread_ctl_list; +}; static struct ecryptfs_kthread_ctl { #define ECRYPTFS_KTHREAD_ZOMBIE 0x00000001 @@ -67,18 +73,13 @@ static int ecryptfs_threadfn(void *ignored) req = list_first_entry(&ecryptfs_kthread_ctl.req_list, struct ecryptfs_open_req, kthread_ctl_list); - mutex_lock(&req->mux); list_del(&req->kthread_ctl_list); - if (!(req->flags & ECRYPTFS_REQ_ZOMBIE)) { - dget(req->lower_dentry); - mntget(req->lower_mnt); - (*req->lower_file) = dentry_open( - req->lower_dentry, req->lower_mnt, - (O_RDWR | O_LARGEFILE), current_cred()); - req->flags |= ECRYPTFS_REQ_PROCESSED; - } - wake_up(&req->wait); - mutex_unlock(&req->mux); + dget(req->lower_dentry); + mntget(req->lower_mnt); + (*req->lower_file) = dentry_open( + req->lower_dentry, req->lower_mnt, + (O_RDWR | O_LARGEFILE), current_cred()); + complete(&req->done); } mutex_unlock(&ecryptfs_kthread_ctl.mux); } @@ -111,10 +112,9 @@ void ecryptfs_destroy_kthread(void) ecryptfs_kthread_ctl.flags |= ECRYPTFS_KTHREAD_ZOMBIE; list_for_each_entry(req, &ecryptfs_kthread_ctl.req_list, kthread_ctl_list) { - mutex_lock(&req->mux); - req->flags |= ECRYPTFS_REQ_ZOMBIE; - wake_up(&req->wait); - mutex_unlock(&req->mux); + list_del(&req->kthread_ctl_list); + *req->lower_file = ERR_PTR(-EIO); + complete(&req->done); } mutex_unlock(&ecryptfs_kthread_ctl.mux); kthread_stop(ecryptfs_kthread); @@ -136,7 +136,7 @@ int ecryptfs_privileged_open(struct file **lower_file, struct vfsmount *lower_mnt, const struct cred *cred) { - struct ecryptfs_open_req *req; + struct ecryptfs_open_req req; int flags = O_LARGEFILE; int rc = 0; @@ -153,17 +153,10 @@ int ecryptfs_privileged_open(struct file **lower_file, rc = PTR_ERR((*lower_file)); goto out; } - req = kmem_cache_alloc(ecryptfs_open_req_cache, GFP_KERNEL); - if (!req) { - rc = -ENOMEM; - goto out; - } - mutex_init(&req->mux); - req->lower_file = lower_file; - req->lower_dentry = lower_dentry; - req->lower_mnt = lower_mnt; - init_waitqueue_head(&req->wait); - req->flags = 0; + init_completion(&req.done); + req.lower_file = lower_file; + req.lower_dentry = lower_dentry; + req.lower_mnt = lower_mnt; mutex_lock(&ecryptfs_kthread_ctl.mux); if (ecryptfs_kthread_ctl.flags & ECRYPTFS_KTHREAD_ZOMBIE) { rc = -EIO; @@ -171,27 +164,14 @@ int ecryptfs_privileged_open(struct file **lower_file, printk(KERN_ERR "%s: We are in the middle of shutting down; " "aborting privileged request to open lower file\n", __func__); - goto out_free; + goto out; } - list_add_tail(&req->kthread_ctl_list, &ecryptfs_kthread_ctl.req_list); + list_add_tail(&req.kthread_ctl_list, &ecryptfs_kthread_ctl.req_list); mutex_unlock(&ecryptfs_kthread_ctl.mux); wake_up(&ecryptfs_kthread_ctl.wait); - wait_event(req->wait, (req->flags != 0)); - mutex_lock(&req->mux); - BUG_ON(req->flags == 0); - if (req->flags & ECRYPTFS_REQ_DROPPED - || req->flags & ECRYPTFS_REQ_ZOMBIE) { - rc = -EIO; - printk(KERN_WARNING "%s: Privileged open request dropped\n", - __func__); - goto out_unlock; - } - if (IS_ERR(*req->lower_file)) - rc = PTR_ERR(*req->lower_file); -out_unlock: - mutex_unlock(&req->mux); -out_free: - kmem_cache_free(ecryptfs_open_req_cache, req); + wait_for_completion(&req.done); + if (IS_ERR(*lower_file)) + rc = PTR_ERR(*lower_file); out: return rc; } diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index 7edeb3d893c1..1c0b3b6b75c6 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -681,11 +681,6 @@ static struct ecryptfs_cache_info { .name = "ecryptfs_key_tfm_cache", .size = sizeof(struct ecryptfs_key_tfm), }, - { - .cache = &ecryptfs_open_req_cache, - .name = "ecryptfs_open_req_cache", - .size = sizeof(struct ecryptfs_open_req), - }, }; static void ecryptfs_free_kmem_caches(void) -- 2.20.1