[PATCH v2 4/6] xfs: add xlog sysfs kobject and attribute handlers

Brian Foster
2014-06-27T12:07:05Z

Embed a kobject into the xfs log data structure (xlog). This creates a
'log' subdirectory for every XFS mount instance in sysfs. The lifecycle
of the log kobject is tied to the lifecycle of the log.

Also define a set of generic attribute handlers associated with the log
kobject in preparation for the addition of attributes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
---
fs/xfs/xfs_log.c | 9 +++++++++
fs/xfs/xfs_log_priv.h | 2 ++
fs/xfs/xfs_sysfs.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++++
fs/xfs/xfs_sysfs.h | 1 +
4 files changed, 64 insertions(+)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 7647818..149a4a5 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -34,6 +34,7 @@
#include "xfs_trace.h"
#include "xfs_fsops.h"
#include "xfs_cksum.h"
+#include "xfs_sysfs.h"

kmem_zone_t *xfs_log_ticket_zone;

@@ -707,6 +708,11 @@ xfs_log_mount(
}
}

+ error = xfs_sysfs_init(&mp->m_log->l_kobj, &xfs_log_ktype, &mp->m_kobj,
+ "log");
+ if (error)
+ goto out_destroy_ail;
+
/* Normal transactions can now occur */
mp->m_log->l_flags &= ~XLOG_ACTIVE_RECOVERY;

@@ -947,6 +953,9 @@ xfs_log_unmount(
xfs_log_quiesce(mp);

xfs_trans_ail_destroy(mp);
+
+ xfs_sysfs_del(&mp->m_log->l_kobj);
+
xlog_dealloc_log(mp->m_log);
}

diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h
index 9bc403a..db7cbde 100644
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -405,6 +405,8 @@ struct xlog {
struct xlog_grant_head l_reserve_head;
struct xlog_grant_head l_write_head;

+ struct xfs_kobj l_kobj;
+
/* The following field are used for debugging; need to hold icloglock */
#ifdef DEBUG
char *l_iclog_bak[XLOG_MAX_ICLOGS];
diff --git a/fs/xfs/xfs_sysfs.c b/fs/xfs/xfs_sysfs.c
index ae9aa7a..88361d7 100644
--- a/fs/xfs/xfs_sysfs.c
+++ b/fs/xfs/xfs_sysfs.c
@@ -18,6 +18,9 @@

#include "xfs.h"
#include "xfs_sysfs.h"
+#include "xfs_log_format.h"
+#include "xfs_log.h"
+#include "xfs_log_priv.h"

struct xfs_sysfs_attr {
struct attribute attr;
@@ -47,3 +50,52 @@ to_attr(struct attribute *attr)
struct kobj_type xfs_mp_ktype = {
.release = xfs_sysfs_release,
};
+
+/* xlog */
+
+static struct attribute *xfs_log_attrs[] = {
+ NULL,
+};
+
+static inline struct xlog *
+to_xlog(struct kobject *kobject)
+{
+ struct xfs_kobj *kobj = to_kobj(kobject);
+ return container_of(kobj, struct xlog, l_kobj);
+}
+
+STATIC ssize_t
+xfs_log_show(
+ struct kobject *kobject,
+ struct attribute *attr,
+ char *buf)
+{
+ struct xlog *log = to_xlog(kobject);
+ struct xfs_sysfs_attr *xfs_attr = to_attr(attr);
+
+ return xfs_attr->show ? xfs_attr->show(buf, log) : 0;
+}
+
+STATIC ssize_t
+xfs_log_store(
+ struct kobject *kobject,
+ struct attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ struct xlog *log = to_xlog(kobject);
+ struct xfs_sysfs_attr *xfs_attr = to_attr(attr);
+
+ return xfs_attr->store ? xfs_attr->store(buf, count, log) : 0;
+}
+
+static struct sysfs_ops xfs_log_ops = {
+ .show = xfs_log_show,
+ .store = xfs_log_store,
+};
+
+struct kobj_type xfs_log_ktype = {
+ .release = xfs_sysfs_release,
+ .sysfs_ops = &xfs_log_ops,
+ .default_attrs = xfs_log_attrs,
+};
diff --git a/fs/xfs/xfs_sysfs.h b/fs/xfs/xfs_sysfs.h
index 438976b..3dcfe80 100644
--- a/fs/xfs/xfs_sysfs.h
+++ b/fs/xfs/xfs_sysfs.h
@@ -20,6 +20,7 @@
#define __XFS_SYSFS_H__

extern struct kobj_type xfs_mp_ktype; /* xfs_mount */
+extern struct kobj_type xfs_log_ktype; /* xlog */

static inline struct xfs_kobj *
to_kobj(struct kobject *kobject)