Re: [RFC][PATCH] inotify 0.10.0

[Robert Love]

On Sun, 2004-09-26 at 22:02 -0400, John McCutchan wrote:

> Announcing the release of inotify 0.10.0. 
> Attached is a patch to 2.6.8.1.

John,

find_inode() can just return an inode directly, so we don't need the
second argument and the double indirection.

FYI, errors can be encoded in pointers via ERR_PTR(), checked via IS_ERR
(), and retrieved via PTR_ERR().

Patch is on top of your patch and all of my previous patches.

	Robert Love

fix_inode() bits

Signed-Off-By: Robert Love <rml@xxxxxxxxxx>

 drivers/char/inotify.c |   19 +++++++++++++------
 1 files changed, 13 insertions(+), 6 deletions(-)

diff -urN linux-inotify/drivers/char/inotify.c linux/drivers/char/inotify.c
--- linux-inotify/drivers/char/inotify.c	2004-09-27 16:04:21.899344440 -0400
+++ linux/drivers/char/inotify.c	2004-09-27 16:03:20.388695480 -0400
@@ -98,24 +98,29 @@
 };
 #define list_to_inotify_kernel_event(pos) list_entry((pos), struct inotify_kernel_event, list)
 
-static int find_inode(const char __user *dirname, struct inode **inode)
+/*
+ * find_inode - resolve a user-given path to a specific inode and iget() it
+ */
+static struct inode * find_inode(const char __user *dirname)
 {
+	struct inode *inode;
 	struct nameidata nd;
 	int error;
 
 	error = __user_walk(dirname, LOOKUP_FOLLOW, &nd);
 	if (error) {
 		iprintk(INOTIFY_DEBUG_INODE, "could not find inode\n");
+		inode = ERR_PTR(error);
 		goto out;
 	}
 
-	*inode = nd.dentry->d_inode;
-	__iget(*inode);
+	inode = nd.dentry->d_inode;
+	__iget(inode);
 	iprintk(INOTIFY_DEBUG_INODE, "ref'd inode\n");
 	inode_ref_count++;
 	path_release(&nd);
 out:
-	return error;
+	return inode;
 }
 
 static void unref_inode(struct inode *inode)
@@ -841,9 +846,11 @@
 	struct inotify_watcher *watcher;
 	err = 0;
 
-	err = find_inode(request->dirname, &inode);
-	if (err)
+	inode = find_inode(request->dirname);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
 		goto exit;
+	}
 
 	if (!S_ISDIR(inode->i_mode))
 		iprintk(INOTIFY_DEBUG_ERRORS, "watching file\n");