xfs: create scaffolding for creating debugfs entries

Set up debugfs directories for xfs as a whole, and a subdirectory for
each mounted filesystem.  This will enable the creation of debugfs files
in the next patch.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
index 74dcb05..e9d317a 100644 (file)
--- a/fs/xfs/xfs_linux.h
+++ b/fs/xfs/xfs_linux.h
@@ -63,6 +63,7 @@ typedef __u32                 xfs_nlink_t;
 #include <linux/rhashtable.h>
 #include <linux/xattr.h>
 #include <linux/mnt_idmapping.h>
+#include <linux/debugfs.h>
 
 #include <asm/page.h>
 #include <asm/div64.h>

diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index e2866e7..0b86bf1 100644 (file)
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -208,6 +208,7 @@ typedef struct xfs_mount {
        uint64_t                m_resblks_avail;/* available reserved blocks */
        uint64_t                m_resblks_save; /* reserved blks @ remount,ro */
        struct delayed_work     m_reclaim_work; /* background inode reclaim */
+       struct dentry           *m_debugfs;     /* debugfs parent */
        struct xfs_kobj         m_kobj;
        struct xfs_kobj         m_error_kobj;
        struct xfs_kobj         m_error_meta_kobj;

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 8185102..31ac474 100644 (file)
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -49,6 +49,7 @@
 
 static const struct super_operations xfs_super_operations;
 
+static struct dentry *xfs_debugfs;     /* top-level xfs debugfs dir */
 static struct kset *xfs_kset;          /* top-level xfs sysfs dir */
 #ifdef DEBUG
 static struct xfs_kobj xfs_dbg_kobj;   /* global debug sysfs attrs */
@@ -758,6 +759,7 @@ static void
 xfs_mount_free(
        struct xfs_mount        *mp)
 {
+       debugfs_remove(mp->m_debugfs);
        kfree(mp->m_rtname);
        kfree(mp->m_logname);
        kmem_free(mp);
@@ -1479,6 +1481,21 @@ xfs_fs_validate_params(
        return 0;
 }
 
+struct dentry *
+xfs_debugfs_mkdir(
+       const char      *name,
+       struct dentry   *parent)
+{
+       struct dentry   *child;
+
+       /* Apparently we're expected to ignore error returns?? */
+       child = debugfs_create_dir(name, parent);
+       if (IS_ERR(child))
+               return NULL;
+
+       return child;
+}
+
 static int
 xfs_fs_fill_super(
        struct super_block      *sb,
@@ -1521,6 +1538,13 @@ xfs_fs_fill_super(
        if (error)
                goto out_free_names;
 
+       if (xfs_debugfs) {
+               mp->m_debugfs = xfs_debugfs_mkdir(mp->m_super->s_id,
+                                                 xfs_debugfs);
+       } else {
+               mp->m_debugfs = NULL;
+       }
+
        error = xfs_init_mount_workqueues(mp);
        if (error)
                goto out_close_devices;
@@ -2353,10 +2377,12 @@ init_xfs_fs(void)
        if (error)
                goto out_cleanup_procfs;
 
+       xfs_debugfs = xfs_debugfs_mkdir("xfs", NULL);
+
        xfs_kset = kset_create_and_add("xfs", NULL, fs_kobj);
        if (!xfs_kset) {
                error = -ENOMEM;
-               goto out_sysctl_unregister;
+               goto out_debugfs_unregister;
        }
 
        xfsstats.xs_kobj.kobject.kset = xfs_kset;
@@ -2400,7 +2426,8 @@ init_xfs_fs(void)
        free_percpu(xfsstats.xs_stats);
  out_kset_unregister:
        kset_unregister(xfs_kset);
- out_sysctl_unregister:
+ out_debugfs_unregister:
+       debugfs_remove(xfs_debugfs);
        xfs_sysctl_unregister();
  out_cleanup_procfs:
        xfs_cleanup_procfs();
@@ -2427,6 +2454,7 @@ exit_xfs_fs(void)
        xfs_sysfs_del(&xfsstats.xs_kobj);
        free_percpu(xfsstats.xs_stats);
        kset_unregister(xfs_kset);
+       debugfs_remove(xfs_debugfs);
        xfs_sysctl_unregister();
        xfs_cleanup_procfs();
        xfs_mru_cache_uninit();

diff --git a/fs/xfs/xfs_super.h b/fs/xfs/xfs_super.h
index 364e2c2..302e6e5 100644 (file)
--- a/fs/xfs/xfs_super.h
+++ b/fs/xfs/xfs_super.h
@@ -100,4 +100,6 @@ extern struct workqueue_struct *xfs_discard_wq;
 
 #define XFS_M(sb)              ((struct xfs_mount *)((sb)->s_fs_info))
 
+struct dentry *xfs_debugfs_mkdir(const char *name, struct dentry *parent);
+
 #endif /* __XFS_SUPER_H__ */