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| author | Al Viro <viro@zeniv.linux.org.uk> | 2013-09-15 20:45:11 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2013-10-24 23:34:48 -0400 |
| commit | 2edbfbf1c1ab0aeb58ce8abfb69b6f6b63542848 (patch) | |
| tree | dc37f9a9aac1cd63c578841b29a039fbe86f48bf /fs/ecryptfs | |
| parent | 3a93e17cf68b01fa29c7a2e861ce508dcd3401ca (diff) | |
| download | lwn-2edbfbf1c1ab0aeb58ce8abfb69b6f6b63542848.tar.gz lwn-2edbfbf1c1ab0aeb58ce8abfb69b6f6b63542848.zip | |
ecryptfs: don't leave RCU pathwalk immediately
If the underlying dentry doesn't have ->d_revalidate(), there's no need to
force dropping out of RCU mode. All we need for that is to make freeing
ecryptfs_dentry_info RCU-delayed.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/ecryptfs')
| -rw-r--r-- | fs/ecryptfs/dentry.c | 30 | ||||
| -rw-r--r-- | fs/ecryptfs/ecryptfs_kernel.h | 5 |
2 files changed, 20 insertions, 15 deletions
diff --git a/fs/ecryptfs/dentry.c b/fs/ecryptfs/dentry.c index 46e31c92e574..8cefa8e13bcc 100644 --- a/fs/ecryptfs/dentry.c +++ b/fs/ecryptfs/dentry.c @@ -44,15 +44,15 @@ */ static int ecryptfs_d_revalidate(struct dentry *dentry, unsigned int flags) { - struct dentry *lower_dentry; - int rc = 1; + struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); + int rc; + + if (!(lower_dentry->d_flags & DCACHE_OP_REVALIDATE)) + return 1; if (flags & LOOKUP_RCU) return -ECHILD; - lower_dentry = ecryptfs_dentry_to_lower(dentry); - if (!(lower_dentry->d_flags & DCACHE_OP_REVALIDATE)) - goto out; rc = lower_dentry->d_op->d_revalidate(lower_dentry, flags); if (dentry->d_inode) { struct inode *lower_inode = @@ -60,12 +60,17 @@ static int ecryptfs_d_revalidate(struct dentry *dentry, unsigned int flags) fsstack_copy_attr_all(dentry->d_inode, lower_inode); } -out: return rc; } struct kmem_cache *ecryptfs_dentry_info_cache; +static void ecryptfs_dentry_free_rcu(struct rcu_head *head) +{ + kmem_cache_free(ecryptfs_dentry_info_cache, + container_of(head, struct ecryptfs_dentry_info, rcu)); +} + /** * ecryptfs_d_release * @dentry: The ecryptfs dentry @@ -74,15 +79,12 @@ struct kmem_cache *ecryptfs_dentry_info_cache; */ static void ecryptfs_d_release(struct dentry *dentry) { - if (ecryptfs_dentry_to_private(dentry)) { - if (ecryptfs_dentry_to_lower(dentry)) { - dput(ecryptfs_dentry_to_lower(dentry)); - mntput(ecryptfs_dentry_to_lower_mnt(dentry)); - } - kmem_cache_free(ecryptfs_dentry_info_cache, - ecryptfs_dentry_to_private(dentry)); + struct ecryptfs_dentry_info *p = dentry->d_fsdata; + if (p) { + if (p->lower_path.dentry) + path_put(&p->lower_path); + call_rcu(&p->rcu, ecryptfs_dentry_free_rcu); } - return; } const struct dentry_operations ecryptfs_dops = { diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index df19d34a033b..e7ad2b3f24a7 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -261,7 +261,10 @@ struct ecryptfs_inode_info { * vfsmount too. */ struct ecryptfs_dentry_info { struct path lower_path; - struct ecryptfs_crypt_stat *crypt_stat; + union { + struct ecryptfs_crypt_stat *crypt_stat; + struct rcu_head rcu; + }; }; /** |