Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751593AbWH3VMJ (ORCPT ); Wed, 30 Aug 2006 17:12:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751596AbWH3VMJ (ORCPT ); Wed, 30 Aug 2006 17:12:09 -0400 Received: from e3.ny.us.ibm.com ([32.97.182.143]:12989 "EHLO e3.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1751593AbWH3VMH (ORCPT ); Wed, 30 Aug 2006 17:12:07 -0400 Date: Wed, 30 Aug 2006 16:12:03 -0500 From: Michael Halcrow To: David Howells Cc: akpm@osdl.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/4] eCryptfs: ino_t to u64 for filldir Message-ID: <20060830211203.GA12953@us.ibm.com> Reply-To: Michael Halcrow References: <20060825221615.GA11613@us.ibm.com> <20060824182044.GE17658@us.ibm.com> <20060824181722.GA17658@us.ibm.com> <22796.1156542677@warthog.cambridge.redhat.com> <27154.1156546746@warthog.cambridge.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <27154.1156546746@warthog.cambridge.redhat.com> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5240 Lines: 157 On Fri, Aug 25, 2006 at 11:59:06PM +0100, David Howells wrote: > I think what you need to do is actually simple. Use iget5 to look > up your inode, using the _pointer_ to the lower inode as the key. > Then just fill in i_ino from the lower inode. The lower inode can't > escape whilst you have it pinned, so the pointer is, in effect, > invariant whilst you are using it. Is this the right approach? Note that I used to depend on iget() to wind up calling ecryptfs_read_inode(); it looks like iget5_locked() does not make that call, so I broke the inode initialization code out into ecryptfs_init_inode(). I now call it explicitly if the I_NEW flag is set, and ecryptfs_read_inode() is now a no-op. I have not tested this under a condition when there is an i_ino conflict, so the ecryptfs_inode_test() code has not been exercised, but I know that the candidate_lower_inode pointer is being set right, so that this would work. --- Modify inode number generation to account for differences in the inode number data type sizes in lower filesystems. Signed-off-by: Michael Halcrow --- fs/ecryptfs/ecryptfs_kernel.h | 4 +++- fs/ecryptfs/inode.c | 15 +++++++++++++++ fs/ecryptfs/main.c | 14 +++++++------- fs/ecryptfs/super.c | 11 +++++++---- 4 files changed, 32 insertions(+), 12 deletions(-) e61cf76bd76643eee6299dc1331a6e2f2d9e01e2 diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index c61ef97..6e4f46e 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -567,6 +567,8 @@ int ecryptfs_send_connector(char *data, u16 msg_flags, pid_t daemon_pid); int ecryptfs_init_connector(void); void ecryptfs_release_connector(void); - +int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode); +int ecryptfs_inode_set(struct inode *inode, void *ignored); +void ecryptfs_init_inode(struct inode *inode); #endif /* #ifndef ECRYPTFS_KERNEL_H */ diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index bfc7f41..331d6d2 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -1022,6 +1022,21 @@ out: return rc; } +int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode) +{ + if (ecryptfs_inode_to_private(inode) && + (ecryptfs_inode_to_lower(inode) + == (struct inode *)candidate_lower_inode)) + return 1; + else + return 0; +} + +int ecryptfs_inode_set(struct inode *inode, void *ignored) +{ + return 0; +} + struct inode_operations ecryptfs_symlink_iops = { .readlink = ecryptfs_readlink, .follow_link = ecryptfs_follow_link, diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index d7a1672..98839bc 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -106,9 +106,6 @@ void __ecryptfs_printk(const char *fmt, * * Interposes upper and lower dentries. * - * This function will allocate an ecryptfs_inode through the call to - * iget(sb, lower_inode->i_ino). - * * Returns zero on success; non-zero otherwise */ int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry, @@ -123,14 +120,17 @@ int ecryptfs_interpose(struct dentry *lo rc = -EXDEV; goto out; } - inode = iget(sb, lower_inode->i_ino); + inode = iget5_locked(sb, lower_inode->i_ino, ecryptfs_inode_test, + ecryptfs_inode_set, lower_inode); if (!inode) { rc = -EACCES; goto out; } - /* This check is required here because if we failed to allocated the - * required space for an inode_info_cache struct, then the only way - * we know we failed, is by the pointer being NULL */ + inode->i_ino = lower_inode->i_ino; + if (inode->i_state & I_NEW) { + ecryptfs_init_inode(inode); + unlock_new_inode(inode); + } if (!ecryptfs_inode_to_private(inode)) { ecryptfs_printk(KERN_ERR, "Out of memory. Failure to " "allocate memory in ecryptfs_read_inode.\n"); diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c index f4f06ea..9caae2c 100644 --- a/fs/ecryptfs/super.c +++ b/fs/ecryptfs/super.c @@ -78,18 +78,19 @@ static void ecryptfs_destroy_inode(struc } /** - * ecryptfs_read_inode + * ecryptfs_init_inode * @inode: The ecryptfs inode * * Set up the ecryptfs inode. */ -static void ecryptfs_read_inode(struct inode *inode) +void ecryptfs_init_inode(struct inode *inode) { /* This is where we setup the self-reference in the vfs_inode's * i_private. That way we don't have to walk the list again. */ ecryptfs_set_inode_private(inode, - list_entry(inode, struct ecryptfs_inode_info, - vfs_inode)); + container_of(inode, + struct ecryptfs_inode_info, + vfs_inode)); ecryptfs_set_inode_lower(inode, NULL); inode->i_version++; inode->i_op = &ecryptfs_main_iops; @@ -97,6 +98,8 @@ static void ecryptfs_read_inode(struct i inode->i_mapping->a_ops = &ecryptfs_aops; } +static void ecryptfs_read_inode(struct inode *inode) { } + /** * ecryptfs_put_super * @sb: Pointer to the ecryptfs super block -- 1.3.3 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/